研究者業績

森 墾

モリ ハルシ  (Harushi MORI)

基本情報

所属
自治医科大学 医学部 放射線医学講座 教授
学位
博士(医学)(東京大学)

J-GLOBAL ID
200901045348273070
researchmap会員ID
1000367575

研究キーワード

 2

経歴

 5

論文

 199
  • Jun-ichi Takanashi, Hitoshi Osaka, Hirotomo Saitsu, Masayuki Sasaki, Harushi Mori, Hidehiro Shibayama, Manabu Tanaka, Yoshiko Nomura, Yasuo Terao, Ken Inoue, Naomichi Matsumoto, A. James Barkovich
    BRAIN & DEVELOPMENT 36(3) 259-263 2014年3月  
    Background: Mutations of POLR3A and POLR3B have been reported to cause several allelic hypomyelinating disorders, including hypomyelination with hypogonadotropic hypogonadism and hypodontia (4H syndrome). Patients and methods: To clarify the difference in MRI between the two genotypes, we reviewed MRI in three patients with POLR3B mutations, and three with POLR3A mutations. Results: Though small cerebellar hemispheres and vermis are common MRI findings with both types of mutations, MRI in patients with POLR3B mutations revealed smaller cerebellar structures, especially vermis, than those in POLR3A mutations. MRI also showed milder hypomyelination in patients with POLR3B mutations than those with POLR3A mutations, which might explain milder clinical manifestations. Conclusions: MRI findings are distinct between patients with POLR3A and 3B mutations, and can provide important clues for the diagnosis, as these patients sometimes have no clinical symptoms suggesting 4H syndrome. (C) 2013 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
  • Masami Goto, Osamu Abe, Shigeki Aoki, Hidemasa Takao, Naoto Hayashi, Tosiaki Miyati, Harushi Mori, Akira Kunimatsu, Kenji Ino, Keiichi Yano, Kuni Ohtomo
    JOURNAL OF MAGNETIC RESONANCE IMAGING 39(1) 132-142 2014年1月  
    PurposeTo show the gray matter volumes in the default mode network (DMN) using the atlas-based method and to evaluate age-related volume change in the DMN region. Estimation of gray matter volumes is interesting research because previous reports showed an association with gray matter volume (GMV) and diseases. Materials and MethodsWe focused on five nodes of the DMN (posterior cingulate, precuneus, lateral temporal cortex [LTC], medial prefrontal cortex, and inferior parietal lobule). In all, 1122 healthy adults were included in the present study. T1-weighted magnetic resonance (MR) images were obtained using a 3T-MR scanner. To investigate GMV in the DMN, segmented gray matter images were measured by the atlas-based method, using Statistical Parametric Mapping 5. Volumes were expressed using three different methods: region of interest (ROI)-volume (mL), the volume itself; ROI-TIV (%), as a percentage of total intracranial volume (individual difference of head size is corrected); and ROI-GMV (%), as a percentage of gray matter volume (individual difference of atrophy speed for aging is corrected). ResultsNegative correlations between measurement values on ROI and age were observed in all five ROIs of the DMN region by two measures of volume (ROI-volume (mL) and ROI-TIV (%)), in both genders. In contrast, positive correlations between measurement values on ROI and age were observed in the posterior cingulate and LTC with ROI-GMV (%), in both genders. ConclusionThe present study is the first report about volume change in the DMN that includes age-related effects. J. Magn. Reson. Imaging 2014;39:132-142. (c) 2013 Wiley Periodicals, Inc.
  • Masami Goto, Osamu Abe, Tosiaki Miyati, Shigeki Aoki, Hidemasa Takao, Naoto Hayashi, Harushi Mori, Akira Kunimatsu, Kenji Ino, Keiichi Yano, Kuni Ohtomo
    Journal of Magnetic Resonance Imaging 38(4) 958-962 2013年10月  
    Purpose To show an association between T2-weighted signal intensity (T2-SI) variation and missegmentation in the putamen of healthy adults, using 3.0-tesla magnetic resonance scanner and voxel-based morphomery (VBM). Materials and Methods Contiguous sagittal T1-weighted images and axial T2-weighted images of the brain were obtained from 1380 healthy participants using a 3.0 Tesla (T) MR scanner. After image preprocessing with Statistical Parametric Mapping 5, the association between T2-SI ratio (= A/B, where A is the mean of the T2-SI in the putamen, and B is that in the thalamus) variation and gray matter missegmentation was assessed using VBM. Results A significant positive correlation was revealed between T2-SI ratio and bilateral putamen volume on the gray matter images. In addition, we found a significant negative correlation between T2-SI ratio and bilateral putamen volume on the white matter images. We consider that these results show the influence of missegmentation. Conclusion To the best of our knowledge, this is the first VBM study to demonstrate an association between T2-SI variation and gray matter missegmentation. These results indicate the possibility that VBM may be more affected by individual differences in iron content levels than by individual differences in tissue volumes if detected-regions with VBM contained substantial iron deposition. Copyright © 2012 Wiley Periodicals, Inc.
  • Masami Goto, Osamu Abe, Shigeki Aoki, Naoto Hayashi, Tosiaki Miyati, Hidemasa Takao, Takeshi Iwatsubo, Fumio Yamashita, Hiroshi Matsuda, Harushi Mori, Akira Kunimatsu, Kenji Ino, Keiichi Yano, Kuni Ohtomo
    NEURORADIOLOGY 55(7) 869-875 2013年7月  
    This study aimed to investigate whether the effect of scanner for cortex volumetry with atlas-based method is reduced using Diffeomorphic Anatomical Registration Through Exponentiated Lie Algebra (DARTEL) normalization compared with standard normalization. Three-dimensional T1-weighted magnetic resonance images (3D-T1WIs) of 21 healthy subjects were obtained and evaluated for effect of scanner in cortex volumetry. 3D-T1WIs of the 21 subjects were obtained with five MRI systems. Imaging of each subject was performed on each of five different MRI scanners. We used the Voxel-Based Morphometry 8 tool implemented in Statistical Parametric Mapping 8 and WFU PickAtlas software (Talairach brain atlas theory). The following software default settings were used as bilateral region-of-interest labels: "Frontal Lobe," "Hippocampus," "Occipital Lobe," "Orbital Gyrus," "Parietal Lobe," "Putamen," and "Temporal Lobe." Effect of scanner for cortex volumetry using the atlas-based method was reduced with DARTEL normalization compared with standard normalization in Frontal Lobe, Occipital Lobe, Orbital Gyrus, Putamen, and Temporal Lobe; was the same in Hippocampus and Parietal Lobe; and showed no increase with DARTEL normalization for any region of interest (ROI). DARTEL normalization reduces the effect of scanner, which is a major problem in multicenter studies.
  • Sachiko Inano, Hidemasa Takao, Naoto Hayashi, Naoki Yoshioka, Harushi Mori, Akira Kunimatsu, Osamu Abe, Kuni Ohtomo
    Journal of Magnetic Resonance Imaging 37(5) 1072-1076 2013年5月  
    Purpose: To investigate age-related differences, gender differences, and age-by-gender interactions on the volumes of 18 neuroanatomical structures, with a large sample at a single institution. Materials and Methods: A total of 861 normal subjects (mean age = 56.1 ± 9.8 years, age range = 24.0-84.8 years) were included in this study. All subjects were scanned at 3.0 T. Measurement of the 18 neuroanatomical volumes was performed with FreeSurfer v. 4.5. Differences in volumes of neuroanatomical structures were tested using analysis of covariance with intracranial volume-normalized volume as the dependent variable, and independent variables of age, sex, age × sex, age × age, age × age × sex, and scanner. Nonsignificant higher-order terms were removed sequentially from the model. A P value of < 0.0028 (=0.5/18) was considered to indicate a statistically significant difference. Results: All neuroanatomical volumes, except for the caudate nucleus, pallidum, and 4th ventricle, were significantly related to age (linearly or quadratically). Significant gender differences were found in all neuroanatomical volumes, except for cerebral white matter, cerebellar cortex, caudate nucleus, and amygdala. No neuroanatomical volume showed a significant interaction between age (age × age) and gender. Conclusion: Our results showed age and gender effects on neuroanatomical volumes, and indicate no gender difference in the aging process of neuroanatomical volumes. © 2012 Wiley Periodicals, Inc.
  • Kouhei Kamiya, Noriko Sato, Miho Ota, Yasuhiro Nakata, Kimiteru Ito, Yukio Kimura, Miho Murata, Harushi Mori, Akira Kunimatsu, Kuni Ohtomo
    JOURNAL OF NEURORADIOLOGY 40(2) 121-129 2013年5月  
    Objectives: The uncinate fasciculus (UF), a major white-matter tract connecting the frontal and temporal lobes, is related to cognitive/behavioral function. Recently, the UF has been suggested to constitute an indirect pathway of the "semantic ventral pathway" in association with the inferior longitudinal fasciculus (ILF). This retrospective study aimed to evaluate damage to the UF and ILF in patients with progressive supranuclear palsy (PSP) using diffusion tensor tract-specific analysis. Material and methods: Diffusion tensor imaging (DTI) of 16 PSP patients with Richardson's syndrome (PSP-RS) and 21 age-matched volunteers were obtained. Fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values for the bilateral UF and ILF were calculated by tract-specific analysis. Student's t test was used to evaluate the differences between the patients and controls. Also, voxel-based morphometry (VBM) was performed using 3D T1-weighted images to explore the regional atrophy of gray matter in the patients. Results: In patients with PSP-RS, FA of the left UF was significantly decreased compared with the controls, while significant increases in ADC were found in the UF and ILF bilaterally. VBM analysis showed significant clusters of reduced gray matter in the frontal cortex (predominantly in the lateral orbitofrontal cortex, pars opercularis and mesial frontal cortex) and subcortical nuclei (midbrain, caudate and thalamic). Conclusion: This study has shown that patients with PSP-RS had impairment of the UF and ILF. Damage to the UF is thought to be related to atrophy of the orbitofrontal cortex and may possibly be correlated with the cognitive/behavioral impairment seen in PSR (C) 2012 Elsevier Masson SAS. All rights reserved.
  • Kouhei Kamiya, Akira Kunimatsu, Harushi Mori, Jiro Sato, Masaaki Akahane, Takana Yamakawa, Kuni Ohtomo
    Japanese Journal of Radiology 31(4) 293-298 2013年4月  
    Purpose: This study aimed to evaluate whether the image quality of virtual monochromatic spectral imaging with fast kVp switching dual-energy CT (DECT) can be comparable to that of 120-kVp single-energy CT (SECT) without increasing the radiation dose. Materials and methods: We retrospectively identified 15 postoperative patients who had undergone both DECT and 120-kVp SECT within a short period of time for follow-up after brain surgery. Simulated 65 keV monochromatic images were reconstructed from DECT data. Subjective image noise, gray-white matter contrast, and overall image quality were rated using a four-point scale. Quantitative measurement of noise, contrast-to-noise ratio (CNR), and posterior fossa beam-hardening artifact were also performed. The figure of merit (FOM), calculated as CNR2/CTDIvol, was used to quantify image quality improvement per exposure risk. Results: The mean CTDIvol was 70.2 ± 0.3 mGy for DECT, which was 11 % lower than SECT (78.9 ± 2.1 mGy). All images were graded above clinically acceptable. Quantitative and qualitative measures for simulated 65-keV images were comparable with SECT images, except for increase in subjective noise. FOM was significantly greater for simulated 65-keV images (P =.03). Conclusion: Our results indicate that virtual monochromatic imaging possibly provides comparable image quality to that afforded by 120-kVp SECT without increasing the dose in routine head CT. © 2013 Japan Radiological Society.
  • K. Kamiya, N. Sato, Y. Nakata, K. Ito, Y. Kimura, M. Ota, A. Takahashi, H. Mori, A. Kunimatsu, K. Ohtomo
    American Journal of Neuroradiology 34(3) 524-532 2013年3月  
    BACKGROUND AND PURPOSE: Restriction of diffusion has been reported in the early phase of secondary neuronal degeneration, such as Wallerian degeneration. The purpose of this study was to investigate postoperative transient reduced diffusion in the ipsilateral striatum and thalamus as a remote effect of surgery. MATERIALS AND METHODS: Six hundred two postoperative MR imaging examinations in 125 patients after cerebral surgery were retrospectively reviewed, focusing on the presence of reduced diffusion in the striatum and/or thalamus. The distribution of reduced diffusion in the striatum was classified into 3 groups: anterior, central, and posterior. Reduced diffusion in the thalamus was also classified on the basis of the anatomic locations of the thalamic nuclei. Further follow-up MRI was available in all patients with postoperative reduced diffusion, and acute infarctions were excluded. The patient medical records were reviewed to evaluate neurologic status. RESULTS: Restriction of diffusion was observed in the striatum and/or thalamus ipsilateral to the surgical site in 17 patients (13.6%). The distribution of signal abnormality correlated with the location of the operation, in concordance with the architecture of the striatocortical and thalamocortical connections. Reduced diffusion was observed from days 7 to 46 after the operation, especially during days 8-21. The signal abnormalities completely resolved on follow-up examinations. The median follow-up period was 202 days (interquartile range, 76-487 days). CONCLUSIONS: Postoperative transient reduced diffusion in the ipsilateral striatum and/or thalamus likely represents an early phase of secondary neuronal degeneration based on its characteristic distribution and time course. Clinically, this reduced diffusion should not be mistaken for postoperative ischemic injury.
  • Masami Goto, Osamu Abe, Shigeki Aoki, Tosiaki Miyati, Hidemasa Takao, Naoto Hayashi, Harushi Mori, Akira Kunimatsu, Kenji Ino, Keiichi Yano, Kuni Ohtomo
    Neuroradiology 55(2) 245-250 2013年2月  
    Introduction: The aim of the present study was to investigate the correlation between local gray matter volume and signal-to-noise ratio on T2-weighted imaging (T2-SNR) of putamen in healthy adults using two tools: voxel-based morphometry (VBM) treating age as a confounding covariate to control for age-related gray matter volume changes and high spatial resolution T1-weighted imaging acquired with a 3.0-T magnetic resonance (3T-MR) scanner. Methods: Contiguous sagittal T1-weighted images and axial T2-weighted images of the brain were obtained from 1,380 healthy participants. T2-SNR of putamen was defined as A/B, where A is the mean T2-weighted signal intensity (T2-SI) in the right and left sides of putamen, and B is the background noise. The software Statistical Parametric Mapping 5 was used for image segmentation. The association between T2-SNR of putamen and gray matter volume was assessed with VBM, treating age as a confounding covariate. Results: A significant positive correlation was obtained between T2-SNR of putamen and bilateral pre- and postcentral gyrus volume. Conclusion: To the best of our knowledge, this is the first VBM study to show an age-independent relationship between T2-SNR of putamen and bilateral pre- and postcentral gyrus volumes in healthy adults. © 2012 Springer-Verlag Berlin Heidelberg.
  • Takanobu Mashiko, Harushi Mori, Harunosuke Kato, Kentaro Doi, Shinichiro Kuno, Kahori Kinoshita, Akira Kunimatsu, Kuni Ohtomo, Kotaro Yoshimura
    Plastic and Reconstructive Surgery - Global Open 1(1) 2013年  
    Background: Hyaluronic acid (HA) fillers have become the most popular tool for wrinkle treatment and volumization, although HA is generally absorbed within 6-12 months and requires repeated treatments to maintain the effects. Methods: HA was injected onto the bone for volumization with a small 30-gauge needle to examine the long-lasting effects. Of the 63 Japanese patients with 97 treated sites followed up more than 12 months, 51 had HA injections for cosmetic purposes and 12 were treated for reconstructive volumization of facial deformity such as localized scleroderma and postsurgical bony deformity. Treated sites included the forehead, temple, nasal root, mentum, tear trough, and infraorbital sulcus. Results: After long-term follow-up (12-93 months, mean = 21.6), persistent volumizing effects were observed in most patients. In fact, 86.6% of the treated sites showed &gt 50% volume retention and 49.5% showed &gt 75% retention. Magnetic resonance imaging analyses revealed that the injected space was well maintained, capsulated, and filled with heterogeneous content. Magnetic resonance imaging quantitative T2 maps indicated that much of the injected HA was replaced with other materials. Together with clinical inspection, these findings suggest that onlay injection of HA on the bone induced formation of capsule, fibrosis, and/or calcification/ ossification, which contributed to persistent volumization. Conclusions: Semipermanent volumizing effects can be achieved by HA injection if the target area has an underlying bony floor. Periosteal stem cells may be activated by HA injection and may contribute to persistent volumizing effects. This treatment may be a much less invasive alternative to fat or bone grafting.
  • Yayoi K. Hayakawa, Hiroki Sasaki, Hidemasa Takao, Harushi Mori, Naoto Hayashi, Akira Kunimatsu, Shigeki Aoki, Kuni Ohtomo
    JOURNAL OF AFFECTIVE DISORDERS 144(3) 263-268 2013年1月  
    Background: Brain structural changes accompany major depressive disorder, but whether subclinical depression is accompanied by similar changes in brain volume and white matter integrity is unknown. By using voxel-based morphometry (VBM) of the gray matter and tract-specific analysis based on diffusion tensor imaging (DTI) of the white matter, we explored the extent to which abnormalities could be identified in specific brain structures of healthy adults with subclinical depression. Methods: The subjects were 21 community-dwelling adults with subclinical depression, as measured by their Center for Epidemiologic Studies Depression Scale (CES-D) scores. They were not demented and had no neurological or psychiatric history. We collected brain magnetic resonance images of the patients and of 21 matched control subjects, and we used VBM to analyze the differences in regional gray matter volume between the two groups. Moreover, we examined the white matter integrity by using tract-specific analysis based on the gray matter volume changes revealed by VBM. Results: VBM revealed that the volumes of both anterior cingulate gyri and the right rectal gyrus were smaller in subclinically depressed women than in control women. Calculation of DTI measures in the anterior cingulum bundle revealed a positive correlation between CES-D scale score and radial diffusivity in the right anterior cingulum in subclinically depressed women. Limitations: The small sample size limits the stability of the reported findings. Conclusions: Gray matter volume reduction and white matter integrity change in specific frontal brain regions may be associated with depressive symptoms in women, even at a subclinical level. (C) 2012 Elsevier B.V. All rights reserved.
  • Masami Goto, Akira Kunimatsu, Masaaki Shojima, Osamu Abe, Shigeki Aoki, Naoto Hayashi, Harushi Mori, Kenji Ino, Keiichi Yano, Nobuhito Saito, Kuni Ohtomo
    MAGNETIC RESONANCE IN MEDICAL SCIENCES 12(1) 53-56 2013年  
    We present a case in which the origin of the branching vessel at the aneurysm neck was observed at the wrong place on the volume rendering method (VR) with 3D time-of-flight MRA (3D-TOF-MRA) with 3-Tesla MR system. In 3D-TOF-MRA, it is often difficult to observe the origin of the branching vessel, but it is unusual for it to be observed in the wrong place. In the planning of interventional treatment and surgical procedures, false recognition, as in the unique case in the present report, is a serious problem. Decisions based only on VR with 3D-TOF-MRA can be a cause of suboptimal selection in clinical treatment.
  • Kazuhiro Tsuchiya, Shigeki Aoki, Keigo Shimoji, Harushi Mori, And Akira Kunimatsu
    Magnetic Resonance in Medical Sciences 12(2) 87-93 2013年  
    Purpose: Time-resolved contrast-enhanced magnetic resonance (MR) angiography (TCMRA) and perfusion MR imaging (PWI) have been used to assess the hemodynamics of brain tumors. We assessed the feasibility and value of consecutive performance of these techniques to evaluate suspected brain metastasis following supplementary injection of gadolinium-based contrast medium. Methods: In 69 patients with suspected brain metastasis, we obtained precontrast MR images followed by TCMRA and postcontrast T1-weighted images after administration of 0.1 mmol/kg gadoteridol. When findings were negative or equivocal, we injected an additional 0.1-mmol/kg dose of gadoteridol and obtained PWI and second postcontrast T1- weighted images. We used a 3-point scale to grade perfusion maps and TCMRA and assessed whether these techniques added information to conventional MR imaging in the differential diagnosis. We also evaluated whether the second contrast injection improved the conspicuity and/or number of enhancing lesions and used a 4-point scoring system to quantitatively analyze diagnostic yield of TCMRA and PWI. Results: We could assess tumor hemodynamics on PWI maps and TCMRA images in all 69 patients. In 14 cases (20%), PWI and/or TCMRA added information to conventional MR findings. After second injection of contrast medium, lesion conspicuity improved in 58 of the 69 cases (84%), and the number of detected lesions increased in 11 of 31 cases diagnosed with metastatic disease (36%). Quantitative analysis revealed TCMRA and PWI provided significant additional diagnostic information (Kruskal-Wallis test, P&lt 0.0001). Conclusion: Consecutive acquisition of TCMRA and PWI using supplementary contrast injection can facilitate differential diagnosis of suspected brain metastasis and improve the number and conspicuity of detected lesions. © 2013 Japanese Society for Magnetic Resonance in Medicine.
  • Kouhei Kamiya, Harushi Mori, Akira Kunimatsu, Kensuke Kawai, Kenichi Usami, Kuni Ohtomo
    JOURNAL OF NEURORADIOLOGY 39(5) 360-363 2012年12月  
    This is a report of two cases of spontaneous temporal encephalocele: one was anteroinferior and presented with epilepsy; the other was posteroinferior and presented with facial neuritis and labyrinthitis. Spontaneous temporal encephalocele is relatively rare and apparently not familiar to a majority of primary physicians. It may present with a variety of symptoms according to its anatomical location, including cerebrospinal fluid fistulas, recurrent meningitis, chronic otitis media, hearing loss, facial nerve palsy and medically intractable epilepsy. Attention should be paid to this disease entity, as it is easily overlooked in imaging studies and can leave serious neurological deficits. (C) 2012 Elsevier Masson SAS. All rights reserved.
  • K. Toyoda, H. Oba, K. Kutomi, S. Furui, A. Oohara, H. Mori, K. Sakurai, K. Tsuchiya, S. Kan, Y. Numaguchi
    AMERICAN JOURNAL OF NEURORADIOLOGY 33(11) 2136-2139 2012年12月  
    IgG4-related disease is characterized by histologic fibrosis with IgG4-positive plasma cell infiltration. Our study evaluated MR imaging features of IgG4-related disease in the head and neck and brain. Images from 15 patients were retrospectively evaluated for the location, signal intensity, and enhancement patterns of lesions. Lacrimal gland enlargement was observed in 8 cases. Other lesions included orbital pseudotumor in 5, pituitary enlargement in 5, and cranial nerve enlargement in 7; the infraorbital nerve was involved in 4. All lesions were hypointense on T2-weighted images, which is typical for IgG4-related lesions. Multiple sites were involved in the head and neck and brain in 11 patients. The diagnosis of IgG4-related disease should be considered in a patient presenting with T2 hypointense lacrimal gland, pituitary, or cranial nerve enlargement, or a T2 hypointense orbital mass, especially if multiple sites in the head and neck are involved in the presence of elevated serum IgG4.
  • Keiko Shimojima, Akihisa Okumura, Harushi Mori, Shinpei Abe, Mitsuru Ikeno, Toshiaki Shimizu, Toshiyuki Yamamoto
    AMERICAN JOURNAL OF MEDICAL GENETICS PART A 158A(9) 2272-2276 2012年9月  
    The 5q14.3 microdeletion syndrome has recently been recognized as a clinical entity manifesting as severe intellectual disability, epilepsy, and brain malformations. Analysis of the shortest region of overlap among patients with this syndrome and subsequent identification of nucleotide alterations in the coding region of myocyte enhancer factor 2C gene (MEF2C) have suggested MEF2C as the gene responsible for the 5q14.3 microdeletion syndrome. We identified a de novo 3.4-Mb deletion of 5q14.3 in a patient with infantile spasms, microcephaly, and brain malformation. The deleted region in the present patient was positional toward the centromere, and MEF2C was not included in the deleted region. However the neurological and dysmorphic features of the present patient resembled those of patients with the 5q14.3 microdeletion syndrome. We consider that a positional effect is the likely explanation for this evidence. To study the precise mechanism of this positional effect, further information is required on patients showing atypical deletions neighboring MEF2C. (C) 2012 Wiley Periodicals, Inc.
  • Ayako Hiraiwa-Sofue, Yoshinori Ito, Harushi Mori, Takashi Ichiyama, Akihisa Okumura
    JOURNAL OF THE NEUROLOGICAL SCIENCES 320(1-2) 145-148 2012年9月  
    Encephalitis/encephalopathy is a rare, but severe, complication of pertussis. Here, we report a case of an unimmunized 7-year-old boy with confirmed pertussis complicated by acute encephalitis/encephalopathy. Eighteen days after the onset of pertussis, generalized seizures began. Magnetic resonance imaging (MRI) indicated that marked demyelination without cytotoxic edema may have occurred to the patient Notably, this is the first report to show precise MRI findings of pertussis-associated encephalitis/encephalopathy. Markedly increased myelin basic protein levels in the cerebrospinal fluid were consistent with the MRI findings. There was no evidence of direct invasion of the causative bacterium or its products into the central nervous system. The levels of interleukin-6 and -10 in the cerebrospinal fluid were higher than those in serum. Taken together, we conclude that indirect immune-mediated mechanisms may have contributed to the pathogenesis of the encephalitis/encephalopathy. (C) 2012 Elsevier B.V. All rights reserved.
  • Harushi Mori, Masayuki Maeda, Jun-ichi Takanashi, Akira Kunimatsu, Nobuyoshi Matsushima, Hidenori Suzuki, Nobuhito Saito, Kuni Ohtomo
    JOURNAL OF CLINICAL NEUROSCIENCE 19(8) 1182-1184 2012年8月  
    Reversible splenial lesions (RSL) of the corpus callosum have been described in various clinical conditions, and some are attributed to the action of antiepileptic drugs (AED). Abrupt withdrawal of an AED in preparation for surgical treatment can result in RSL of the corpus callosum in patients with trigeminal neuralgia who do not have epilepsy. We report two patients who developed RSL following surgical treatment of trigeminal neuralgia. Since our two patients did not have epilepsy, it is strongly suggested that the AED, rather than convulsive status epilepticus, could be a contributing factor in RSL. The pathogenesis of AED-associated RSL is not clear. Similar RSL can appear under various circumstances, implying that factors other than AED can influence a common end-point mechanism that results in RSL. Nevertheless, delirium after surgery may be a cue for inquiring about RSL. This condition is transient and represents a clinicoradiological syndrome with an excellent prognosis. We should consider this phenomenon in the perioperative period after surgery for trigeminal neuralgia to avoid invasive diagnostic and therapeutic procedures. (c) 2011 Elsevier Ltd. All rights reserved.
  • Masaki Katsura, Harushi Mori, Akira Kunimatsu, Hiroki Sasaki, Osamu Abe, Toru Machida, Kuni Ohtomo
    NEURORADIOLOGY 54(8) 873-882 2012年8月  
    Immunoglobulin (Ig) G4-related disease is a recently designated benign clinical entity histopathologically characterized by sclerosing inflammation and infiltration of numerous IgG4+ plasma cells that affects multiple organs. The purpose of this study is to characterize the imaging findings of patients with histopathologically proven IgG4-related disease in the head, neck, and brain. A total of 17 patients (15 males, 2 females; mean age, 66.1 +/- 7.4 years) with histopathologically proven IgG4-related disease in the head, neck, and brain were identified in two hospitals between January 2004 and December 2010. Imaging findings were retrospectively reviewed, with particular attention to the location and number of lesions, internal architecture, enhancement patterns, presence of vascular occlusion or compression, and changes in adjacent bones. The lesions, presented as either enlarged gland(s), or focal, localized nodules/masses, were distributed in the lacrimal gland (n = 7), the parotid gland (n = 14), the submandibular gland (n = 10), the pituitary gland (n = 2), skull base dura mater (n = 2), and the pterygopalatine fossa (n = 3). All lesions were well-defined and iso- to hypointense on T2-weighted magnetic resonance images and showed homogeneous enhancement. No lesion showed vascular occlusion or compression. Bones adjacent to the lesions showed remodeling (erosion or sclerosis) without signs of destruction (n = 6). Four patients had lesions involving multiple areas which extended along the trigeminal nerve, accompanied by expansion of neural foramina along their courses, with no signs of bone destruction. Sites of predilection for IgG4-related disease in the head, neck, and brain include the lacrimal, salivary, and pituitary glands. Recognition of the typical radiological features of IgG4-related disease, such as well-defined lesion borders, T2 hypointensity, homogeneous and gradual enhancement pattern, absence of vascular occlusion or compression, and presence of bone remodeling without destruction, may be of help in the diagnosis of this benign clinical entity.
  • Taichi Kin, Hirofumi Nakatomi, Masaaki Shojima, Minoru Tanaka, Kenji Ino, Harushi Mori, Akira Kunimatsu, Hiroshi Oyama, Nobuhito Saito
    JOURNAL OF NEUROSURGERY 117(1) 78-88 2012年7月  
    Object. In this study, the authors used preoperative simulation employing 3D computer graphics (interactive computer graphics) to fuse all imaging data for brainstem cavernous malformations. The authors evaluated whether interactive computer graphics or 2D imaging correlated better with the actual operative field, particularly in identifying a developmental venous anomaly (DVA). Methods. The study population consisted of 10 patients scheduled for surgical treatment of brainstem cavernous malformations. Data from preoperative imaging (MRI, CT, and 3D rotational angiography) were automatically fused using a normalized mutual information method, and then reconstructed by a hybrid method combining surface rendering and volume rendering methods. With surface rendering, multimodality and multithreshold techniques for 1 tissue were applied. The completed interactive computer graphics were used for simulation of surgical approaches and assumed surgical fields. Preoperative diagnostic rates for a DVA associated with brainstem cavernous malformation were compared between conventional 2D imaging and interactive computer graphics employing receiver operating characteristic (ROC) analysis. Results. The time required for reconstruction of 3D images was 3-6 hours for interactive computer graphics. Observation in interactive mode required approximately 15 minutes. Detailed anatomical information for operative procedures, from the craniotomy to microsurgical operations, could be visualized and simulated three-dimensionally as 1 computer graphic using interactive computer graphics. Virtual surgical views were consistent with actual operative views. This technique was very useful for examining various surgical approaches. Mean (+/- SEM) area under the ROC curve for rate of DVA diagnosis was significantly better for interactive computer graphics (1.000 +/- 0.000) than for 2D imaging (0.766 +/- 0.091; p &lt; 0.001, Mann-Whitney U-test). Conclusions. The authors report a new method for automatic registration of preoperative imaging data from CT, MRI, and 3D rotational angiography for reconstruction into I computer graphic. The diagnostic rate of DVA associated with brainstem cavernous malformation was significantly better using interactive computer graphics than with 2D images. Interactive computer graphics was also useful in helping to plan the surgical access corridor. (http://thejns.org/doi/abs/10.3171/2012.3.JNS111541)
  • Masami Goto, Osamu Abe, Tosiaki Miyati, Hiroyuki Kabasawa, Hidemasa Takao, Naoto Hayashi, Tomomi Kurosu, Takeshi Iwatsubo, Fumio Yamashita, Hiroshi Matsuda, Harushi Mori, Akira Kunimatsu, Shigeki Aoki, Kenji Ino, Keiichi Yano, Kuni Ohtomo
    KOREAN JOURNAL OF RADIOLOGY 13(4) 391-402 2012年7月  
    Objective: Many studies have reported pre-processing effects for brain volumetry; however, no study has investigated whether non-parametric non-uniform intensity normalization (N3) correction processing results in reduced system dependency when using an atlas-based method. To address this shortcoming, the present study assessed whether N3 correction processing provides reduced system dependency in atlas-based volumetry. Materials and Methods: Contiguous sagittal T1-weighted images of the brain were obtained from 21 healthy participants, by using five magnetic resonance protocols. After image preprocessing using the Statistical Parametric Mapping 5 software, we measured the structural volume of the segmented images with the WFU-PickAtlas software. We applied six different bias-correction Levels (Regularization 10, Regularization 0.0001, Regularization 0, Regularization 10 with N3, Regularization 0.0001 with N3, and Regularization 0 with N3) to each set of images. The structural volume change ratio (%) was defined as the change ratio (%) = (100 x [measured volume - mean volume of five magnetic resonance protocols] / mean volume of five magnetic resonance protocols) for each bias-correction level. Results: A low change ratio was synonymous with lower system dependency. The results showed that the images with the N3 correction had a lower change ratio compared with those without the N3 correction. Conclusion: The present study is the first atlas-based volumetry study to show that the precision of atlas-based volumetry improves when using N3-corrected images. Therefore, correction for signal intensity non-uniformity is strongly advised for multi-scanner or multi-site imaging trials.
  • Yuri Kitamura, Akihisa Okumura, Masaharu Hayashi, Harushi Mori, Satoru Takahashi, Keiko Yanagihara, Rie Miyata, Naoyuki Tanuma, Takashi Mimaki, Shinpei Abe, Toshiaki Shimizu
    BRAIN & DEVELOPMENT 34(5) 372-375 2012年5月  
    Glucose transporter type 1 deficiency syndrome is an inborn error of glucose transport across blood tissue barriers, and the modified Atkins diet is an effective and well-tolerated treatment. To investigate the effects of the modified Atkins diet, we examined the cerebrospinal fluid markers and performed phosphorus magnetic resonance spectroscopy in a patient with glucose transporter type 1 deficiency syndrome before and after the modified Atkins diet. Cerebrospinal fluid levels of the oxidative stress markers, 8-hydroxy-2'-deoxyguanosine and hexanoyl-lysine adduct, were markedly increased above the cutoff index and were normalized 18 months after the modified Atkins diet. Phosphorus magnetic resonance spectroscopy measurements showed 18% increase of PCr/gamma-ATP ratio after the modified Atkins diet. These results suggest that the modified Atkins diet may reduce oxidative stress in the brain and improve energy reserve capacity, which is important in sustaining electrophysiological activities essential for performing brain functions. (C) 2011 The Japanese Society of Child Neurology. Published by Elsevier B.V. All rights reserved.
  • Harushi Mori, A. Kunimatsu, O. Abe, H. Sasaki, H. Takao, T. Nojo, K. Kawai, N. Saito, K. Ohtomo
    Neuroradiology Journal 25(2) 163-171 2012年4月  
    It has been suggested that a difference in signal intensity (SI) between the resection cavity and normal cerebrospinal fluid (CSF) on fluid-attenuated inversion recovery (FLAIR) magnetic resonance imaging (MRI) in partially resected gliomas indicates subsequent or coincident tumor progression. We considered that this would hold true for resected meningiomas as well. Hence, we aimed to assess whether or not such a difference in the SI during the follow-up evaluation helps predict residual or recurrent tumor in resected meningiomas. We evaluated 63 patients with resected meningiomas. The SI within the resection cavity observed on FLAIR images was qualitatively and quantitatively assessed during follow-up. Qualitative analysis comprised visual comparison of the SI in the resection cavity with that of normal CSF by neuroradiologists. The SI in the resection cavity was quantitatively assessed by region of interest (ROI) analysis and normalized against the background noise and CSF SI. Normalized SI recorded during follow-up was compared with that recorded immediately after resection. Tumor progression was defined as a 20% or greater increase in the diameter of the longest residual or recurrent meningioma (Response Evaluation Criteria in Solid Tumors). The sensitivity and specificity of the elevated SI in the resection cavity for indicating residual or recurrent tumor were calculated. Qualitative analysis by FLAIR MRI showed that patients with remnant tumor following surgery had a prolonged SI increase in the resection cavity. Further, SI increase could not always be observed before recurrence, and both SI increase and regrowth remnant/recurrence could be detected in the same MRI examination. In resected meningiomas, leakage of tumor elements into the resection cavity, presumably tumor cells, manifests as an SI increase on FLAIR images and indicates residual or recurrent tumor. However, unlike the previous reports on partially resected gliomas, we concluded that the SI change does not always precede tumor progression or recurrence.
  • Masami Goto, Tosiaki Miyati, Osamu Abe, Hidemasa Takao, Tomomi Kurosu, Naoto Hayashi, Shigeki Aoki, Harushi Mori, Akira Kunimatsu, Kenji Ino, Keiichi Yano, Kuni Ohtomo
    JOURNAL OF DIGITAL IMAGING 25(1) 173-178 2012年2月  
    The aims of this study were to (1) investigate the repeatability of measured volumes using the atlas-based method in each area of the brain, and (2) validate our hypothesis that the repeatability of the measured volumes with the atlas-based method was improved by using smoothed images. T1-weighted magnetic resonance images were obtained in five healthy subjects using the 1.5-T scanner. We used Statistical Parametric Mapping 5 and WFU PickAtlas software (theory of the Talairach brain atlas). Volumes inside region-of-interest (ROI) were measured in ten sets (five subjects x right and left) on six ROIs, respectively. One set comprises five images (one subject x five 3D-T1WIs). The percentage change was defined as [ 100 x (measured volume-mean volume in each set)/mean volume in each set)]. As a result, the average percentage changes using non-smoothed image on each ROI were as follows: gray matter, 0.482%; white matter, 0.375%; cerebrospinal fluid images, 0.731%; hippocampus, 0.864%; orbital gyrus, 1.692%; cerebellum posterior lobe, 0.854%. Using smoothed images with large FWHM resulted in improved repeatability on orbital gyrus. This is the first report of repeatability in each brain structure and improved repeatability with smoothed images using the atlas-based method.
  • Masami Goto, Osamu Abe, Hiroyuki Kabasawa, Hidemasa Takao, Tosiaki Miyati, Naoto Hayashi, Tomomi Kurosu, Takeshi Iwatsubo, Fumio Yamashita, Hiroshi Matsuda, Sachiko Inano, Harushi Mori, Akira Kunimatsu, Shigeki Aoki, Kenji Ino, Keiichi Yano, Kuni Ohtomo
    MAGNETIC RESONANCE IN MEDICAL SCIENCES 11(1) 27-34 2012年  
    Purpose: We aimed to show that correcting image distortion significantly affects brain volumetry using voxel-based morphometry (VBM) and to assess whether the processing of distortion correction reduces system dependency. Materials and Methods: We obtained contiguous sagittal T-1-weighted images of the brain from 22 healthy participants using 1.5- and 3-tesla magnetic resonance (MR) scanners, preprocessed images using Statistical Parametric Mapping 5, and tested the relation between distortion correction and brain volume using VBM. Results: Local brain volume significantly increased or decreased on corrected images compared with uncorrected images. In addition, the method used to correct image distortion for gradient nonlinearity produced fewer volumetric errors from MR system variation. Conclusion: This is the first VBM study to show more precise volumetry using VBM with corrected images. These results indicate that multi-scanner or multi-site imaging trials require correction for distortion induced by gradient nonlinearity.
  • Akira Kunimatsu, Yuichi Suzuki, Kazuchika Hagiwara, Hiroki Sasaki, Harushi Mori, Masaki Katsura, Kuni Ohtomo
    MAGNETIC RESONANCE IN MEDICAL SCIENCES 11(3) 205-211 2012年  
    Susceptibility-weighted angiography (SWAN) is a state-of-the-art 3-dimensional (3D) T-2*-weighted imaging (T-2*WI) technique with multiple echo acquisitions, but its clinical utility remains to be determined. We compared the utility of susceptibility-weighting sequences among SWAN, 3D phase-sensitive magnetic resonance (MR) imaging (PSI), and conventional 2-dimensional (2D) T-2*WI in routine clinical practice. Our results indicate that SWAN can achieve susceptibility weighting more effectively than conventional 2D T-2*WI and as effectively as PSI and requires a much shorter scan time than PSI.
  • Masami Goto, Osamu Abe, Tosiaki Miyati, Takeharu Yoshikawa, Naoto Hayashi, Hidemasa Takao, Sachiko Inano, Hiroyuki Kabasawa, Harushi Mori, Akira Kunimatsu, Shigeki Aoki, Kenji Ino, Kyouhito Iida, Keiichi Yano, Kuni Ohtomo
    NEURORADIOLOGY 53(8) 617-622 2011年8月  
    Previous studies revealed a correlation between local brain volume and cognitive function. The aim of the present study was to investigate the correlation between local gray matter volume and the Wechsler Memory Scale-Revised (WMS-R) logical/verbal memory (WMS-R-verbal) score in healthy adults using a 3 Tesla magnetic resonance scanner and voxel-based morphometry (VBM). T1-weighted magnetic resonance images were obtained in 1,169 healthy adults. The T1-weighted images in native space were bias-corrected, spatially normalized, and segmented into gray matter, white matter, and cerebrospinal fluid images with Statistical Parametric Mapping 5. To investigate regionally the specific effects of the WMS-R-verbal score on the gray matter images, simple regression analysis was performed by VBM treating age, total intracranial volume, and gender as confounding covariates. A P value of less than 0.05 corrected with false discovery rate in voxel difference was considered to be statistically significant. Our study showed a significant positive correlation between the WMS-R-verbal score and the bilateral entorhinal cortex volume. In the right entorhinal, T value is 4.75, and the size of the clusters is 155 voxels. In the left entorhinal, T value is 4.08, and the size of the clusters is 23 voxels. A significant negative correlation was not found. To our knowledge, this is the first VBM study showing that entorhinal cortex volume is positively correlated with the WMS-R-verbal score for healthy subjects. Therefore, in our structural neuroimaging study, we add evidence to the hypothesis that the entorhinal cortex is involved in verbal memory processing.
  • Masami Goto, Osamu Abe, Tosiaki Miyati, Sachiko Inano, Naoto Hayashi, Shigeki Aoki, Harushi Mori, Akira Kunimatsu, Kenji Ino, Kyouhito Iida, Keiichi Yano, Kuni Ohtomo
    Radiological Physics and Technology 4(2) 185-188 2011年7月  
    Our aim in the present additional study was to investigate the absolute hippocampal volume in normal adults who were divided into eight groups according to their age and gender, because our previous study with voxel-based morphometry (VBM) was not able to show the absolute hippocampal volume. High-spatial-resolution T1-weighted images with 3.0 Tesla magnetic resonance scanners were obtained on 412 healthy adults who were divided into 8 groups, according to age and gender, for analysis of brain volume change focusing on hippocampal volume. Hippocampal regions of interest were obtained with WFU PickAtlas software. As a result, the present study revealed a significant difference bilaterally between the groups of females in their forties and those in their fifties. Because this result is the same as that of our previous study with VBM, it adds evidence to the hypothesis that menopause is associated with hippocampal volume reduction. However, the result between groups of males in their sixties and those in their seventies was inconsistent in both studies. In conclusion, the present study showed that reduction in the hippocampal volume over one decade was small compared to the standard deviation in each group. This study is useful for improving our understanding of the correlation between menopause and hippocampal volume reduction. © 2011 Japanese Society of Radiological Technology and Japan Society of Medical Physics.
  • Masami Goto, Osamu Abe, Tosiaki Miyati, Sachiko Inano, Naoto Hayashi, Shigeki Aoki, Harushi Mori, Hiroyuki Kabasawa, Kenji Ino, Keiichi Yano, Kyouhito Iida, Kazuo Mima, Kuni Ohtomo
    JOURNAL OF MAGNETIC RESONANCE IMAGING 33(1) 48-53 2011年1月  
    Purpose: To clarify age-related structural changes specific to hippocampal volume by hierarchizing according to age, gender, and menopausal status. Many studies report the neuroprotective effects of estrogen and age-related brain volume changes; however, there are no studies regarding age-related change specific to hippocampal volume in terms of age, gender, and menopausal status. Materials and Methods: T1-weighted MR images were obtained in 412 healthy adults divided into eight groups according to age and gender, to analyze brain volume change focusing on hippocampal volume. Results: Voxel-based morphometry (VBM) revealed significantly smaller gray matter volume in the hippocampus bilaterally in females aged in their fifties (51 of 59 females were at menopause) compared with females in their forties (3 of 46 females were at menopause). No significant difference was found, however, between female groups in their fifties versus sixties, or sixties versus seventies; or between male groups in their forties versus fifties, fifties versus sixties, or sixties versus seventies. In addition, VBM revealed significant hippocampal volume reduction bilaterally in all postmenopausal women compared with all premenopausal women. Conclusion: The results of the current study suggest that the menopause may be associated with hippocampal volume reduction.
  • Mizuho Murakami, Harushi Mori, Akira Kunimatsu, Osamu Abe, Hirotaka Chikuda, Takashi Ono, Hiroyuki Kabasawa, Kazuyuki Uchiumi, Jiro Sato, Shiori Amemiya, Shuhei Komatsu, Kuni Ohtomo
    JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY 35(1) 16-20 2011年1月  
    Objective: Magnetic resonance imaging (MRI) is the most popular follow-up study for patients who have undergone spinal surgery. However, the image quality often becomes poor because of artifacts from metal implants and/or from failed fat suppression, which obscure diagnosis. Iterative decomposition of water and fat with echo asymmetry and least-squares estimation (IDEAL) is a new fat suppression method that is less affected by inhomogeneity of the magnetic field. Here, we compared postsurgical spinal MRI with IDEAL versus chemical shift selective saturation (CHESS). Methods: For 35 patients who had spinal surgery, we examined T2-weighted fast spin-echo sagittal images of the spine with both IDEAL and CHESS. Two radiologists evaluated the degrees of fat suppression and spinal canal projection from 0 (least/worst) to 2 (most/best). Results: Fat suppression and spinal canal scores for IDEAL were statistically higher than those for CHESS (P &lt; 0.05). Conclusions: Iterative decomposition of water and fat with echo asymmetry and least-squares estimation is clinically useful for postoperative spinal MRI.
  • Takashi Ueta, Harushi Mori, Akira Kunimatsu, Takuhiro Yamaguchi, Yasuhiro Tamaki, Yasuo Yanagi
    Ophthalmology 118 2011年1月1日  
  • Y. Nakata, N. Sato, T. Masumoto, H. Mori, H. Akai, H. Nobusawa, Y. Adachi, H. Oba, K. Ohtomo
    AMERICAN JOURNAL OF NEURORADIOLOGY 31(10) 1944-1950 2010年11月  
    BACKGROUND AND PURPOSE: MR imaging findings of LYH and pituitary adenomas are similar, but the therapeutic strategies are completely different. The purpose of this study was to evaluate seller and parasellar MR imaging findings in patients with both diseases, as well as characteristic clinical findings. MATERIALS AND METHODS: Clinical findings, including endocrinologic study and MR images of 20 patients with LYH and 22 patients with pituitary adenoma, were retrospectively reviewed. We evaluated the MR images in relation to the following: 1) the PPHI on T1-weighted images, 2) thickened stalk (&gt;3.5 mm), 3) pituitary symmetry, 4) pituitary enhancement pattern, 5) a dural tail, and 6) parasellar signal intensity on T2- and T1-weighted images. RESULTS: Between patients with LYH and those with pituitary adenoma, a significant difference was identified for the number of patients with loss of PPHI, thickened stalk, pituitary symmetry, homogeneous enhancement, and parasellar dark signal intensity on T2-weighted images by statistical analysis (Fisher exact probability test, P &lt; .05). Among them, only parasellar dark signal intensity on T2-weighted images had no false-positive cases. CONCLUSIONS: The parasellar T2 dark sign can be a specific finding used to distinguish pituitary adenoma from LYH.
  • Sachiko Inano, Daisuke Itoh, Hidemasa Takao, Naoto Hayashi, Harushi Mori, Akira Kunimatsu, Osamu Abe, Shigeki Aoki, Kuni Ohtomo
    CLINICAL IMAGING 34(5) 332-336 2010年9月  
    Purpose: The objective of this study was to examine the frequency of high signal intensity in the dural sinuses of normal subjects upon magnetic resonance (MR) angiography using 3.0-T scanners. Methods: A total of 748 consecutive healthy subjects underwent three-dimensional time-of-flight MR angiography at 3.0 T. Sixteen subjects were excluded. MR angiographic source images were retrospectively reviewed for the presence of high signal intensity in the inferior petrosal sinus, pterygoid sinus, or sigmoid sinus. Results: Of the 732 examinations, 10 (1.3%) showed high signal intensity in the dural sinuses (left inferior petrosal sinus, n=4; left pterygoid sinus, n=3; left sigmoid sinus, n=6). High signal intensity in the dural sinuses was observed only on the left side. The minimum diameter of the left brachiocephalic vein was significantly smaller in subjects with high signal intensity than in the control group. Conclusion: In our study with healthy subjects at 3.0 T, the frequency of high signal intensity in the dural sinuses is as low as 1.3%. Retrograde flow due to physiological stenosis of the left brachiocephalic vein may be one of the causes of this phenomenon. (C) 2010 Elsevier Inc. All rights reserved.
  • Kanako Kunishima, Masahiro Shin, Akira Kunimatsu, Shigeki Aoki, Hiroki Sasaki, Tomoyuki Koga, Daisuke Itoh, Harushi Mori, Osamu Abe, Kuni Ohtomo, Nobuhito Saito
    NEUROSURGERY 67(1) 100-109 2010年7月  
    BACKGROUND: The reported cumulative risk of post-angiographic obliteration (post-AO) hemorrhage from arteriovenous malformations (AVMs) following gamma knife radiosurgery (GKRS) over 10 years is 2.2%. OBJECTIVE: To identify the warning signs of post-AO hemorrhage by analyzing the characteristics of enhancement on contrast-enhanced MRI magnetic resonance imaging (MRI) of AVMs with post-AO hemorrhage. METHODS: We performed a retrospective analysis of 121 patients whose AVMs were angiographically obliterated within 5 years of GKRS without hemorrhage and who received at least 1 contrast-enhanced MRI after GKRS (group 1), and 7 patients who experienced post-AO hemorrhage (group 2). We analyzed the enhancement persistence ratio (the percentage of AVMs with persisting enhancement on contrast-enhanced T1-weighted image after obliteration) and the change in size of the enhanced region over time in each patient. RESULTS: The enhancement persistence ratio showed no significant difference between the 2 groups (89.4% vs 100% for groups 1 and 2, respectively; P = .401). While most cases in group 1 showed a tendency to decrease in size and gradually stabilize following GKRS, there were significantly more cases in group 2 with obvious increment of the enhanced regions within 1 year of angiographic obliteration compared with the previous measurement (4.96% vs 71.4% for groups 1 and 2, respectively; P &lt; .0001). CONCLUSION: Our results suggest that AVMs that show an increase in the size of the enhanced region within 1 year of angiographic obliteration should be followed up with caution for post-AO hemorrhage. Persisting enhancement itself is not positively associated with subsequent hemorrhage.
  • Masaaki Hori, Harushi Mori, Shigeki Aoki, Osamu Abe, Tomohiko Masumoto, Satoshi Kunimatsu, Kuni Ohtomo, Hiroyuki Kabasawa, Nobuyuki Shiraga, Tsutomu Araki
    MAGNETIC RESONANCE IMAGING 28(4) 594-598 2010年5月  
    Object: Although three-dimensional (3D), high-spatial resolution susceptibility-weighted imaging (SWI) appears to be valuable in the evaluation of central nervous system gliomas, several evaluation methods are proposed in the literature. The purpose of this study was to evaluate the use of 3D SWI for grading intracranial gliomas with various analysis methods. Materials and Methods: Twenty-three patients suspected of having gliomas participated in this study. SWI was performed in addition to conventional MR sequences. In 15 cases, post-gadolinium enhanced SWI was also obtained. Imaging evaluation criteria were conventional grade, hypointensity ratio in the tumor-dominant structure of hypointensity on SWI (hemorrhage or vascular structure) and presence of abnormal enhancement surrounding the tumor. Results: Mean grading scores of conventional grade showed no statistically significant difference among WHO grades. Mean grading scores of hypointensity ratios in the tumor were higher for WHO Grades 3 and 4 than for lower grade tumors (P=.05, Mann Whitney U test). Hemorrhagic foci were more frequently seen in the higher grade tumor. Post-contrast susceptibility-weighted images of five of 11 WHO Grade 3 and 4 cases showed bright enhancement surrounding the tumor, suggesting a breakdown of the blood brain barrier. Conclusions: SWI at 3 T may be a useful method to analyze the structural characteristics of gliomas and to evaluate pathology in vivo. Assessment of hypointensity ratios in the glioma was the most preferable method in grading glioma. However, more studies, specifically concerning a suitable method for image analysis, are needed to establish SWI at 3 T as a useful tool in clinical routine. (C) 2010 Elsevier Inc. All rights reserved.
  • Harushi Mori
    Brain and Nerve 62(5) 501-509 2010年5月1日  
    Here, we review of the efficacy of radioimaging method in the diagnosis of the spinal cord and spine disorders. The simplest solution for a successful diagnosis is to scan wide field in each image. Nothing will start unless one recognizes the imaging findings. Analysis based on the MECE principle, mutually exclusive and collectively exhaustive, is performed in four ways, that is deductive, fractionation, longitudinal and priority methods. Because purpose determines the means, structual constructivism suggests that one should employ the appropriate method depending on the situation (interest-correlative approach). The practical conventional procedure to attain a diagnosis is as follows. First identify the location of the lesion by using MRI or other modalities. The location of the lesion shorten the list of differential diagnosis. Second, obtain maximum information on the characteristics of the lesion in order to speculate the pathology. Third, look for any associated findings such as tortuous vasculature around the spinal cord. Fourth, refer to all the available information for example, chief complaint, clinical history, previous history, family history, physical findings, physiological findings, laboratory data, previous images, other modalities and so on. And finally, one should consult with the attending physician and colleagues when in doubt. However, because rationality (mathematical expectation: posterior probability or positive predictive value with positive findings), predicted utility, and emotions affect human beings while making decisions, it seems impossible to completely avoid oversights and misdiagnosis.
  • Harushi Mori
    Japanese Journal of Clinical Radiology 55 279-288 2010年2月1日  
    An approach for easy diagnosis of intradural disorders is reviewed. First of all, we must specify the location of the intradural lesion on MRI or other modalities. The location constrains the list of differential diagnosis. Second, we should detail the property of the lesion to speculate the pathology. Third, we should search any associated findings such as tortuous vasculature around the spinal cord. Forth, we should refer all information possible. And finally, we should consult with colleague.
  • Kanako Sato, Shigeki Aoki, Nobue K. Iwata, Osamu Abe, Harushi Mori, Kuni Ohtomo
    Brain and Nerve 61(11) 1259-1268 2009年11月  
    Classic magnetic resonance imaging (MRI) findings in patients with amyotrophic lateral sclerosis (ALS) are subtle, but some findings have been reported such as signal changes in the primary motor cortex and the corticospinal tract (CST). Only a few reports have discussed MRI findings of ALS with dementia (ALS-D), in which frontotemporal atrophy and hyperintensity in subcortical white matter of bilateral temporal tips have been reported. Recent development of diffusion tensor imaging (DTI) techniques allows us to extract specific white matter tracts and to analyze them quantitatively, i.e. we can visualize the CST and can also measure its integrity using DTI parameters such as fractional anisotropy (FA) or apparent diffusion coefficient (ADC). In patients with ALS, general decrease in FA and increase in ADC in the CST have been reported. In patients with ALS-D, several authors detected decrease in fractional anisotropy in the corpus callosum, the thalamus, frontal/parietal/ temporal, the cingulate gyrus, and the uncinate fasciculus in addition to the CST. Voxel based morphometry or statistical analysis of imaging are the newly developed methods which enable to make objective and reliable imaging analysis based on automated procedure using standardized database. We also presented several researches using these techniques. In this article, we reviewed classic imaging findings and recent development of MRI including DTI and statistical imaging analysis in patients with ALS/ALS-D.
  • Kanako Kunishima, Harushi Mori, Daisuke Itoh, Shigeki Aoki, Hiroyuki Kabasawa, Tomoyuki Koga, Keisuke Maruyama, Tomohiko Masumoto, Osamu Abe, Kuni Ohtomo
    JOURNAL OF NEUROSURGERY 110(3) 492-499 2009年3月  
    Object. Although conventional catheter angiography is commonly used in the evaluation of intracranial arteriovenous malformations (AVMs), less invasive tools are more suitable for screening or follow-up. Older MR angiography techniques cannot provide high enough temporal and spatial resolution for assessing AVMs. Three-tesla time-resolved imaging of contrast kinetics (TRICKS)-a time-resolved, contrast-enhanced 3D MR angiography technique-achieves subsecond time resolution without sacrificing spatial resolution. The purpose of this study was to assess the accuracy of TRICKS at 3 T in the evaluation of AVMs. Methods. Between November 2006 and November 2007, 31 patients who were known to have AVMs underwent evaluation in a 3-T unit with the TRICKS technique. The TRICKS images were then evaluated independently by 2 radiologists for nidus detection, early venous filling detection, and Spetzler-Martin classification, and these results were compared, with the results of catheter angiography. Results. Time-resolved imaging of contrast kinetics achieved 96% sensitivity and 100% specificity both in nidus detection and early venous filling detection. The Spetzler-Martin grades also showed excellent correlation with catheter angiography findings (kappa = 0.89). Conclusions. Although this is a preliminary study, the authors&apos; results indicate that time-resolved contrast-enhanced 3D MR angiography at 3 T is a good tool to assess AVMs, and has the potential to replace catheter angiography in screening or follow-up examinations of patients with AVMs. (DOI: 10.3171/2008.7.JNS08173)
  • Takeharu Yoshikawa, Shigeki Aoki, Osamu Abe, Naoto Hayashi, Yoshitaka Masutani, Tomohiko Masumoto, Harushi Mori, Yoshiroh Satake, Kuni Ohtomo
    RADIATION MEDICINE 26(8) 481-487 2008年10月  査読有り
    Purpose. The aim of the study was to estimate the effect of distortion correction with correspondence to numbers of encoding directions to acquire diffusion tensor imaging (DTI) of improved quality. Materials and methods. Ten volunteers underwent DTI of the head using echo planar imaging with 6, 13, 27, and 55 encoding directions. Fractional anisotropy (FA) maps and apparent diffusion coefficient (ADC) maps were created before and after distortion correction. Regions of interest were placed in the corpus callosum on each map, and standard deviations of FA and ADC were calculated. FA maps were also evaluated visually by experienced neuroradiologists. Results. Dispersion of standard deviations tended to be reduced after distortion correction, with significant differences found in FA maps with 6 encoding directions, ADC maps with 6 directions, and ADC maps with 13 directions (P &lt; 0.001, P &lt; 0.005, and P &lt; 0.05, respectively). Visual image quality was improved after distortion correction (P &lt; 0.01 for all of the visual comparisons). Conclusion. Distortion correction is effective in providing DTI of enhanced quality, notwithstanding the number of encoding directions.
  • Takeharu Yoshikawa, Shigeki Aoki, Osamu Abe, Naoto Hayashi, Yoshitaka Masutani, Tomohiko Masumoto, Harushi Mori, Yoshiroh Satake, Kuni Ohtomo
    Radiation Medicine - Medical Imaging and Radiation Oncology 26(8) 481-487 2008年10月  
    Purpose. The aim of the study was to estimate the effect of distortion correction with correspondence to numbers of encoding directions to acquire diffusion tensor imaging (DTI) of improved quality. Materials and methods. Ten volunteers underwent DTI of the head using echo planar imaging with 6, 13, 27, and 55 encoding directions. Fractional anisotropy (FA) maps and apparent diffusion coefficient (ADC) maps were created before and after distortion correction. Regions of interest were placed in the corpus callosum on each map, and standard deviations of FA and ADC were calculated. FA maps were also evaluated visually by experienced neuroradiologists. Results. Dispersion of standard deviations tended to be reduced after distortion correction, with significant differences found in FA maps with 6 encoding directions, ADC maps with 6 directions, and ADC maps with 13 directions (P < 0.001, P < 0.005, and P < 0.05, respectively). Visual image quality was improved after distortion correction (P < 0.01 for all of the visual comparisons). Conclusion. Distortion correction is effective in providing DTI of enhanced quality, notwithstanding the number of encoding directions. © 2008 Japan Radiological Society.
  • Mio Sakai, Shigeki Aoki, Yusuke Inoue, Ryuichi Ashida, Haruyasu Yamada, Shigeru Kiryu, Sachiko Inano, Harushi Mori, Yoshitaka Masutani, Osamu Abe, Kuni Ohtomo, Hironobu Nakamura
    JOURNAL OF COMPUTER ASSISTED TOMOGRAPHY 32(5) 822-824 2008年9月  
    We report a patient with linear scleroderma en coup de sabre without neurological symptoms despite the presence of large white matter lesions. The patient underwent 3.0-T magnetic resonance (MR) examinations including diffusion tensor imaging, time-resolved contrast-enhanced MR angiography, susceptibility-weighted imaging, and proton MR spectroscopy. These imaging findings suggested increased vascular permeability and microbleeding without abnormalities of metabolites. Our observation is consistent with vasculopathy and may be helpful in the proper diagnosis and treatment of linear scleroderma en coup de sabre.
  • Masami Goto, Yuuichi Suzuki, Osamu Abe, Naoto Hayashi, Shigeki Aoki, Harushi Mori, Tomohiko Masumoto, Yasushi Watanabe, Yoshirou Satake, Kenji Ino, Keiichi Yano, Kyouhito Iida, Kazuo Mima, Kuni Ohtomo
    Radiological physics and technology 1(2) 196-200 2008年7月  
    A voxel-based specific regional analysis system for Alzheimer's disease (VSRAD) was used for quantitative analysis of parahippocampal atropy with 1.5-tesla (T) MRI in a voxel-wise manner. The analysis of images acquired under a different imaging condition provides an error factor that has a calculated value. Clinical application of 3T-MRI is necessary for establishing a normal data base (N-DB) specific for 3T-MRI data, which permits appropriate application of VSRAD. We established an N-DB specific for 3T-MRI for use in VSRAD. The "Z-score of the parahippocampal gyrus" was 0.79 +/- 0.32, and the N-DB of each age group did not have a big deflection when we analyzed a group of physically unimpaired persons in an N-DB specific for 3T-MRI. Therefore, we were able to confirm the validity of the customized N-DB. The "Z-score of the parahippocampal gyrus" was 1.62 +/- 0.47 for the N-DB of VSRAD. The numerical value was high for the group of physically unimpaired persons.
  • Harushi Mori
    Clinical Neurology 48(11) 945-946 2008年  
    Diffusion tensor imaging of magnetic resonance imaging, including diffusion tensor tractography, is a unique tool to visualize and segment the white matter pathways in vivo and one can evaluate the segmented trace quantitatively. Three dimensional visualization of the white matter fibers, such as corticospinal (pyramidal) tracts, with relationship to brain lesions (infarcts, vascular malformations and brain tumors) is extremely helpful for stereotactic radiosurgery, preoperative evaluation and intraoperative navigation. Quantitative measurement of the tract is a very sensitive method to detect differences in the tract in neurodegenerative/neurocognitive/psychiatric patients such as amyotrophic lateral sclerosis, schizophrenia and Alzheimer diseases. Importance of this tool will become more significant in clinical and neuroscience fields in the future.
  • Yoshinori Fujishiro, Kazunari Nakao, Kenta Watanabe, Yasuhiro Ebihara, Naoki Nakamura, Harushi Mori, Naoto Hayash, Takahiro Asakage
    ACTA OTO-LARYNGOLOGICA 127 151-156 2007年12月  
    Conclusion. This superselective intra-arterial intervention technique enabled us to administer a higher dose of cisplatinum to the local lesion with a lower incidence of adverse issues by use of neutralizer, compared with the conventional methods. Objective. A wide variety of modalities, including surgery, radiotherapy, and chemotherapy, alone or in combination, have been reported for the treatment of maxillary sinus cancer. However, there is still much controversy with regard to the optimum treatment to obtain better local control and acceptable preservation of shape and function. Since 2001, we have performed superselective intra-arterial infusion chemotherapy in combination with radiotherapy and surgery aiming at a higher local control rate. Patients and methods. This was a review of prospective collected data. The therapeutic design consisted of weekly intra-arterial infusion of high dose CDDP with concomitant radiotherapy and planned surgery performed during chemo-radiation therapy. From June 2001 to January 2004, 14 patients with squamous cell carcinoma of maxillary sinus underwent this treatment procedure at the University of Tokyo Hospital. Results. The local response rate with this combined therapy was 85.7%. Overall survival rates at 1 and 2 years were 78.6% and 56.2%, respectively, with median follow-up of 25.5 months.
  • H. Mori, A. Yagishita, T. Takeda, T. Mizutani
    AMERICAN JOURNAL OF NEURORADIOLOGY 28(8) 1511-1516 2007年9月  
    BACKGROUND AND PURPOSE: Our aim was to clarify imaging findings of amyotrophic lateral sclerosis with dementia (ALSD). MATERIALS AND METHODS: T2-weighted MR images (T2WI) of 3 patients with ALSD (2 men, 1 woman; 58-71 years of age) and 21 patients with ALS without dementia (12 men, 9 women; 46-74 years of age) were examined for frontotemporal lobar atrophy and signal-intensity alterations in the white matter of the anterior temporal lobes, corticospinal tracts (CST), and precentral gyri and in precentral cortices. The brain of one of the patients with ALSD was examined at autopsy. RESULTS: All patients with ALSD showed bilateral frontotemporal atrophy mostly with temporal lobe dominance. In the ALSD group, T2WI demonstrated hyperintensity in the subcortical white matter on the medial side of the anterior temporal lobes, whereas in the group without dementia, none showed this imaging finding. MR images demonstrated no abnormal signal-intensity changes in CST in the internal capsule or the brain stem in the ALSD group. In the group without dementia, 6 patients (28.6%) showed this imaging finding, In neuropathologic examinations of the brain of 1 patient with ALSD, myelin-stained sections of the brain demonstrated loss of myelin in the subcortical white matter on the medial side of the anterior temporal white matter. CONCLUSIONS: A symmetric pattern of frontotemporal atrophy and anteromedial subcortical hyperin-tensities in the temporal lobes on T2WI could be characteristic of ALSD.
  • M. Ihara, N. Yamasaki, A. Hagiwara, A. Tanigaki, A. Kitano, R. Hikawa, H. Tomimoto, M. Noda, M. Takanashi, H. Mori, N. Hattori, T. Miyakawa, M. Kinoshita
    Neuron 53(4) 519-533 2007年2月  査読有り
  • Harushi Mori, Shigeki Aoki, Kuni Ohtomo
    Magnetic Resonance in Medical Sciences 6(3) 183-184 2007年  

MISC

 131
  • Emiko Chiba, Hiroyuki Fujii, Harushi Mori
    No shinkei geka. Neurological surgery 52(4) 705-717 2024年7月  
    Meningiomas are the most common brain tumors, often in the form of extra-axial masses adhering to the dura mater. Although there are typical imaging findings, meningiomas have a wide variety of imaging findings, owing to their different histological subtypes. Thus, it can be difficult to differentiate meningiomas from other diseases that present with similar imaging findings. This section outlines mimickers for monitoring meningiomas that present with imaging findings similar to those of meningiomas. Diseases that form masses and require differentiation from meningiomas include schwannomas, solitary fibrous tumors, dural metastases, and histiocytosis. Diseases that primarily present as dural thickening and require differentiation from meningiomas include hypertrophic duralitis, fungal infections, and IG4-related diseases. Notably, in addition to the various pathologies that can mimic meningiomas, such as those listed above, there are also cases in which the diagnosis of meningioma is difficult because of additional modifications, such as metastasis or meningioma infarction.
  • 池田 欣正, 濱本 耕平, 紙 恭子, 小澤 耕一郎, 真鍋 治, 千葉 英美子, 森 墾, 真鍋 徳子
    自治医科大学紀要 46 65-71 2024年3月  
    【目的】Single energy metal artifact reduction(SEMAR)を用いた血管塞栓用コイルの金属アーチファクト低減における撮影条件の影響を明らかにする。【方法】チューブ内に血管塞栓用コイルを留置した血管塞栓ファントムを用い,管電圧,管電流,撮影方向を変えてCTを撮影し,視覚評価,standard deviation(SD)値,CT値のプロファイル曲線を指標として,それぞれの金属アーチファクト低減における影響を比較検討した。【結果】すべての管電圧,管電流において,SEMARありではSEMARなしと比較し視覚評価スコアは高値を示し,SD値は低値を示した。SEMARありの画像では,高管電圧および高管電流撮影でSD値は低値を示した。撮影方向の検討では,チューブに対して水平に撮影した画像でチューブ内の金属アーチファクトがより広範囲にみられた。【結論】SEMARを用いた金属アーチファクト低減には,高管電圧,高管電流での撮影が有用であり,評価対象血管と金属コイルとの位置関係を考慮した方向での撮影が重要である。(著者抄録)
  • 磯崎 丈範, 松木 充, 國友 直樹, 渡辺 友里子, 神澤 純, 小島 綜一郎, 大竹 悠子, 藤井 裕之, 森 墾, 天野 雄介
    Japanese Journal of Radiology 42(Suppl.) 16-16 2024年2月  
  • 高橋 宏典, 國友 直樹, 木島 茂喜, 濱本 耕平, 森 墾
    日本インターベンショナルラジオロジー学会雑誌 38(3) 184-189 2024年1月  
  • 濱本 耕平, 真鍋 徳子, 大石 茉耶, 山本 彩季, 渡辺 友里子, 小島 綜一郎, 森 墾
    映像情報Medical 55(7) 9-15 2023年6月  

書籍等出版物

 56

講演・口頭発表等

 84

共同研究・競争的資金等の研究課題

 3