五味 玲

Numerous reports have demonstrated the usefulness of bioresorbable materials, but few have described severe complications caused by delayed degradation. The authors present the case of an intracranial foreign body granuloma caused by plates made of unsintered hydroxyapatite (uHA) particles and poly-L-lactide (PLLA; Super Fixsorb MX, Takiron) after cranioplasty. This 1-month-old boy presented to the authors' department with Pfeiffer syndrome. He had multiple-suture synostosis causing turribrachycephaly, Chiari malformation Type 1, and obstructive sleep apnea syndrome. At 6 months old, the child was treated with multidirectional cranial distraction osteogenesis. The uHA-PLLA plates were applied as base stones to reinforce the pins. After 16 days of distraction and 3 weeks of consolidation, the pins were removed. Seventeen months postoperatively, the plate on the right temporal bone showed passive intraosseous translocation (PIT), and by 2 years postoperatively, the plate was completely left behind in the cerebrum. At 3.5 years postoperatively, MRI disclosed a contrast-enhanced mass with surrounding brain edema at the site of the plate. The lesion was resected. The clinical history and histological specimens led to a diagnosis of foreign body granuloma surrounding the nonabsorbed resorbable plate in the dura mater. Resorbable plates are clearly useful resources in cases in which delayed absorption will not prove problematic, but careful application and follow-up is required when dealing with the growing skull given the possibility of intracranial displacement after PIT.

Cytosolic isocitrate dehydrogenase 1 (IDH1) with an R132H mutation in brain tumors loses its enzymatic activity for catalyzing isocitrate to alpha-ketoglutarate (alpha-KG) and acquires new activity whereby it converts alpha-KG to 2-hydroxyglutarate. The IDH1 mutation induces down-regulation of tricarboxylic acid cycle intermediates and up-regulation of lipid metabolism. Sterol regulatory element-binding proteins (SREBPs) regulate not only the synthesis of cholesterol and fatty acids but also acyclin-dependent kinase inhibitor p21 that halts the cell cycle at G1. Here we show that SREBPs were up-regulated in U87 human glioblastoma cells transfected with an IDH1(R132H)-expression plasmid. Small interfering ribonucleic acid (siRNA) for SREBP1 specifically decreased p21 messenger RNA (mRNA) levels independent of the p53 pathway. In IDH1(R132H)-expressing U87 cells, phosphorylation of Retinoblastoma (Rb) protein also decreased. We propose that metabolic changes induced by the IDH1 mutation enhance p21 expression via SREBP1 and inhibit phosphorylation of Rb, which slows progression of the cell cycle and may be associated with non-aggressive features of gliomas with an IDH1 mutation.

This study aims to ascertain which specific types of sacrococcygeal dimples are associated with underlying spinal cord malformations. From 2008 to 2011, we prospectively examined children less than 2 years old with sacrococcygeal dimples. Each patient underwent clinical assessment of dimples and magnetic resonance imaging. We devised the following new classification of dimples according to their location: type 1, dimples located within the gluteal crease, including coccygeal pits; type 2, dimples located at the upper edge of the gluteal crease with associated curving or deformity of that crease; and type 3, dimples located well above the gluteal crease. We evaluated 142 patients with sacrococcygeal dimples. Although we identified spinal malformations such as spinal lipomas, filum cysts, and thickened fila terminalia in only 17 % of infants with type 1 dimples, we observed them in 45 % with type 2 and 55 % with type 3. Thus, in terms of the rate of spinal malformations, there are significant differences between types 1 and 2 and between types 1 and 3. We propose a new classification of sacrococcygeal dimples. Although type 2 dimples have previously been classified as simple dimples that require no further investigation, we have identified that they are strongly associated with spinal deformities, comparable to atypical type 3 dimples. Thus, both types 2 and 3 dimples warrant radiological investigation.

A case of unclassified, pediatric cerebral neuroepithelial tumor in a 10-year-old girl that showed remarkable radiosensitivity is reported. MRI revealed a brain tumor of mixed intensity with heterogeneous enhancement in the medial temporal lobe, extending to the basal ganglia. The tumor was partially removed. On pathology, the main part of the tumor showed immature features: the tumor cells had a chromatin-rich large nucleus and less cytoplasm, and mitoses and fragmentation of the nuclei were frequent. On immunohistochemistry, the tumor cells were negative for glial fibrillary acidic protein (GFAP) and synaptophysin and positive for Olig2. The maximum MIB-1 index was 70%. The part invading into the surrounding brain showed similarities in form to a highly anaplastic astrocytoma. The infiltrating tumor cells were positive for GFAP and less positive for Olig2. After 40 Gy radiation, the residual tumor was markedly reduced. Neuroepithelial tumors rarely show such high radiosensitivity, and the reason for the radiosensitivity in the present case may have been the immaturity of the tumor cells.

われわれは,2003年より頭蓋縫合早期癒合症に対し,外固定型の骨延長装置を用いた治療法,Multidirectional Cranial Distraction Ostegenesis(MCDO)法を行っている.これまで行った23症例を検討した結果,内固定型に比べ形態の改善度に勝り,装置除去時の手術侵襲の軽減が得られた.また初回手術の侵襲,合併症の軽減,延長期間の短縮も計られたことから,MCDO法は骨延長法の適応の拡大に寄与する優れた術式と考えられる.