Takahiro Tomita

New Dried Human Amniotic Membrane Is Useful as a Substitute for Dural Repair after Skull Base Surgery

Objectives Cerebrospinal fluid (CSF) leakage is an undesirable complication of skull base surgery. We used dried human amniotic membrane (AM) as a patch graft for dural repair to determine its efficacy in preventing CSF leakage. Design Frontoparietal craniotomy and removal of dura were performed in 20 Wistar rats. A dried AM was placed to cover the dural defect without suturing in 16 animals. In four animals, an expanded polytetrafluoroethylene was implanted. At 2 weeks and 1, 3, and 6 months, histological examination was performed. Dried AM was also used as a substitute in 10 patients who underwent skull base surgery, after approval by the Ethics Committee of the University of Toyama. Results At 2 weeks after implantation, thick connective tissue completely enclosed the dried AM. At 1 month after implantation, the connective tissue became thin and the implanted AM shortened. At 3 and 6 months after implantation, histological examination revealed disappearance of the dried AM and formation of membranous tissue. In the clinical study, neither CSF leakage nor clinical adverse reactions directly related to the dried AM were observed. Conclusion Dried human AM appears to be an ideal substitute for dura, since it is replaced by natural tissue.

One-piece Pedunculated Frontotemporal Orbitozygomatic Craniotomy by Creation of a Subperiosteal Tunnel beneath the Temporal Muscle: Technical Note

OBJECTIVE We have developed a simple and easy modification of the orbitozygomatic approach using one-piece pedunculated craniotomy. This modification prevents atrophy of the temporal muscle, resulting in temporal fossa depression and atrophy of the free bone graft resulting in the occurrence of bone pits along the line of the craniotomy. METHODS The key points of this modification are as follows. The scalp flap is elevated in the plane between the superficial and deep layers of the temporal fascia. The temporal muscle is dissected from the temporal plane by performing subperiosteal elevation with intact insertion to the superior temporal line of the temporal muscle, which results in the creation of a subperiosteal tunnel beneath the temporal muscle. The one-piece fronto-orbitozygomatic bone flap is hinged on the temporal muscle. RESULTS After the surgeons had received full training in the procedures and anatomic findings related to this craniotomy in 10 cadaveric heads, surgery was performed for paraclinoid or parasellar tumors in five patients. Although temporary pulsatile exophthalmos occurred after surgery in one patient, no craniotomy-related complications occurred during or after surgery. Because the bone flap is fragile at the frontozygomatic suture, fixation with a small titanium plate was required in three of five patients at the end of the operation. All patients were pleased with the cosmetic results of surgery during a minimum follow-up period of 6 months. CONCLUSION The modifications described in this article reduce the risk of atrophy of the temporal muscle and improve the cosmetic results without limitation of operative exposure.

Multiple meningiomas consisting of fibrous meningioma and anaplastic meningioma

A 61-year-old woman presented with progressive dementia over a period of 4 months. Computed tomographic (CT) scans and magnetic resonance (MR) imaging showed 2 meningiomas located at the left parasagittal region and the left sphenoid ridge. These tumors had distinct MRI findings; the left parasagittal tumour showed a clear peritumoral CSF space without brain oedema, but the sphenoid ridge tumour was large with marked peritumoral oedema. Total excision of these 2 tumours was attempted with favourable clinical improvement and histological studies revealed meningiomas of different histological types. The left parasagittal tumour was a fibrous meningioma and the left sphenoid ridge tumour was an anaplastic meningioma with typical brain invasion. These tumours showed a MIB-1 staining index of 1% and 30%, respectively. There was also a difference in the immunohistochemical findings for neurofibromin (NF1 product) expression; the left parasagittal tumour expressed neurofibromin but the left sphenoid ridge tumour lacked neurofibromin expression, suggesting an NF1-gene mutation. This case may be a rare example of the simultaneous occurrence of meningiomas with distinct genotypes.

Sinus thrombosis in idiopathic hypereosinophilic syndrome causing fatal cerebral haemorrhage.

Idiopathic hypereosinophilic syndrome (HES) is a leukoproliferative disorder that is characterized by sustained overproduction of eosinophils and a trend towards damage to specific organs, usually the cardiovascular system. We report the case of a 76-year-old woman who was affected by idiopathic HES, which had an unusual and rapidly fatal course. Sinus thrombosis in the transverse and sigmoid sinuses was evident on cranial CT and CT angiography. In our review of the English-language literature we were unable to find any previously published direct images of sinus thrombosis in idiopathic HES.

Impact of a novel biomarker, T-LAK cell-originating protein kinase (TOPK) expression on outcome in malignant glioma: TOPK as a novel biomarker for glioma

This study aimed to evaluate the biological features of T‐lymphokine‐activated killer cell‐originating protein kinase (TOPK) in vitro and to assess clinical impact of TOPK on the outcome in patients with malignant glioma. TOPK protein level and TOPK mRNA and protein levels in six glioma cell lines were examined using Western blot and reverse transcription‐polymerase chain reaction (RT‐PCR), respectively. Immunohistochemistry was performed to examine their subcellular localization of TOPK. Using surgical specimens from 57 patients with gliomas, TOPK and Ki‐67 expressions were examined by immunohistochemistry. Their co‐localization was also examined with double immunofluorescence immunohistochemistry. Impacts of TOPK/Ki‐67 expression on the overall survival (OS) and progression‐free survival (PFS) in 32 patients with glioblastoma multiforme (GBM) were examined, using Kaplan–Meier and Cox proportion hazard models. Immunohistochemistry revealed that approximately 20–30% of glioma cells were positive for TOPK in vitro. TOPK mRNA was identified in all glioma cell lines on RT‐PCR. The value of TOPK/GAPDH was 0.27 ± 0.11. TOPK and Ki‐67 expressions were significantly higher in GBM patients than in non‐GBM patients. A majority of TOPK‐positive cells were also positive for Ki‐67 and vice versa. Multivariate analysis revealed that a low TOPK expression (≤ 12.7%) was an independent predictor of longer OS (P = 0.0372), and that gross total removal and a low TOPK expression (≤ 12.7%) were independent predictors of longer PFS (P = 0.0470 and P = 0.0189, respectively). The findings strongly suggest biological and clinical importance of TOPK expression in gliomas, indicating a novel therapeutic potential of TOPK inhibitors to treat malignant gliomas.

Novel biomarker, phosphorylated T-LAK cell-originated protein kinase (p-TOPK) can predict outcome in primary central nervous system lymphoma

This study aimed to assess whether T‐lymphokine‐activated killer cell‐originated protein kinase (TOPK) can be a potent novel biomarker to predict the outcome in patients with primary central nervous system lymphoma (PCNSL). This study enrolled 20 patients who were histologically diagnosed as having diffuse large B‐cell type PCNSL between 2005 and 2015. Using surgical specimens, the expression of TOPK and phosphorylated TOPK (p‐TOPK) was analyzed on immunohistochemistry. Clinical features such as age, sex, Karnofsky performance status (KPS), ocular involvement, deep brain structure involvement, the number of lesions, chemotherapy and radiation therapy were also collected. Impacts of TOPK/p‐TOPK expression on their progression‐free survival (PFS) and overall survival (OS) were examined with multivariate analysis. Median PFS/OS were 24.2 and 39.0 months, respectively. On immunostaining, the mean percentage of TOPK‐positive cells was 35.5 ± 20.8%, and the mean number of p‐TOPK‐positive cells was 13.7 ± 15.7 cells/mm2. The higher expression of p‐TOPK was significantly related to multiple lesions (P = 0.003). Multivariate analysis demonstrated that only the higher expression of p‐TOPK was an independent predictor to shorten both PFS (P = 0.029; hazard ratio (HR), 5.5; 95% confidential interval (CI), 1.2–25.3) and OS (P = 0.014; HR, 7.7; 95% CI, 1.5–41.3). These findings strongly suggest that p‐TOPK may be a potent biomarker to determine the outcome of patients with PCNSL and to develop novel drugs to treat PCNSL.

Lacunar Stroke, Cavernous Angioma, and Fusiform Aneurysm Due to Irradiation for Pilocytic Astrocytoma—A Case Report

Radiotherapy is a useful modality for the treatment of brain tumors, but may induce brain degeneration, tumor formation, and vasculopathy in the irradiated field. We describe a rare case of a pediatric patient who presented multiple different types of vascular events consecutively in the irradiated field including lacunar stroke because of occlusion of perforating artery, intraventricular hemorrhage from cavernoma, and subarachnoid hemorrhage because of the rupture of fusiform aneurysm, 6 years after radiotherapy against pilocytic astrocytoma. The life-threatening aneurysm was resected, and its histologic findings revealed the radiation-induced vasculopathy. We should avoid irradiation, and repeat surgical resection for the pediatric cases with pilocytic astrocytoma. Once irradiation was indicated for them, however, we should carefully follow-up not only tumor recurrence but also angiograms to predict any cerebrovascular events.

Moyamoya Disease Emerged with Corpus Callosum Hemorrhage: A 3D Computer Graphic Analysis

The authors present a rare case of moyamoya disease emerged with corpus callosum hemorrhage. A 31-year-old woman suddenly complained of severe headache followed by consciousness disturbance. Radiological examinations revealed the bleeding in the splenium of corpus callosum, which was associated with intraventricular hemorrhage. On cerebral angiography, the carotid fork was severely stenotic on both sides, and a marked dilatation was observed in the anterior/posterior choroidal arteries and posterior pericallosal artery as well as the lenticulostriate arteries. Therefore, she was diagnosed as moyamoya disease. She successfully underwent superficial temporal artery to middle cerebral artery (STA–MCA) anastomosis and indirect bypass on both sides. Postoperative course was uneventful. Follow-up cerebral angiography performed 4 months after surgery showed well-developed surgical collaterals via the external carotid system and a marked decrease of the dilated moyamoya vessels. She has been free from any cerebrovascular events for 36 months after surgery. Radiological findings strongly suggest that splenial bleeding occurred due to the rupture of the dilated abnormal collateral vessels that originate from the medial posterior choroidal artery and penetrate the corpus callosum in this case. Three-dimensional computer graphic analysis was useful to determine the complex collateral circulation in moyamoya disease.

Peculiar venous lesions in fatal hyponatremic brain edema.

A 19‐year‐old woman with a 3‐year history of schizophrenia suddenly began to vomit, and rapidly developed a coma an hour after the onset of vomiting. A brain CT scan showed diffuse brain edema with compression of the ventricles. Laboratory tests showed a low serum sodium concentration of 117 mmol/L. She died 67 h after the onset of the first symptom. A postmortem examination showed diffuse swelling of the brain with bilateral uncal and tonsillar herniations. Histologically, no necrotic, hemorrhagic or encephalitic changes were seen. However, microvacuolar changes with lymphocytic infiltration were found in the venous walls (media and adventitia) mainly in the basal ganglia, thalamus and brainstem. To our knowledge, this is the first demonstration of venous alterations in fatal hyponatremic brain edema. These changes may have participated in the exacerbation of the brain edema due to functional disturbance of venous drainage.