Hideyuki Tomita

Concurrent unilateral moyamoya disease and vertebrobasilar junction aneurysm associated with fenestration – Case report and management

The incidence of fenestration of the basilar artery has been eported to be 1.3–6% in autopsy series and less than 1% in angigraphic series [1]. Similar to that noted in arterial bifurcations, enestrations also have a tendency to develop aneurysms [1]. The ncidence of aneurysms is reported to be 7% with basilar fenesrations, and the incidence of fenestrations with vertebrobasilar unction aneurysm is reported to be 35.5% [2]. Intracranial aneurysms are occasionally accompanied by moymoya disease. These aneurysms are generally classified into 3 ubtypes: aneurysms at major arteries, aneurysms at distal periphral arteries, and aneurysms of moyamoya vessels [3]. Aneurysms t major arteries are likely to occur in the posterior circulation. he gradual reduction of the perfusion in the anterior circulation ue to chronic stenosis and occlusion of the internal carotid artery ICA) increase the hemodynamic stress in the posterior circulation, hich may contribute to the development of aneurysms [4].

Giant Cell Tumor of the Skull: Review of the Literature.

BACKGROUND Giant cell tumors (GCTs) are rare in the skull. The present report describes a case with a primary GCT located in the temporal bone and reviews the relevant literature. We also propose a treatment strategy for GCT of the skull. CLINICAL PRESENTATION A 41-year-old man presented with headache and auditory disturbance. Radiologic images showed a lytic expansive extradural lesion originating primarily from the right temporal bone and expanding into the middle cranial fossa and the infratemporal fossa. A biopsy specimen of the lesion was obtained from the external auditory meatus. Total removal was performed with temporal craniectomy, mandibular condylar process removal, tympanoplasty, and mastoidectomy. DISCUSSION The rate of recurrence of GCTs is related to complete resection and location of the GCT rather than to the degree of invasiveness. Some of the mononuclear cells and stromal cells in GCT express receptor activator of nuclear factor κ-β ligand (RANKL). Because inhibition of RANKL and bisphosphonate therapy might eliminate giant cells, this approach might be useful for recurrent or unresectable GCTs of the skull. CONCLUSIONS Preoperative diagnosis by biopsy is important in determining the therapeutic strategy of GCTs. Complete resection is important to reduce the recurrence rate of GCTs in the skull.

Medulloblastoma in Older Adults: A Case Report and Literature Review

BACKGROUND Medulloblastoma is a malignant tumor of the posterior fossa and is predominantly seen in children younger than 15 years of age. This tumor is uncommon in adults, especially those older than 40 years of age, and reports of cases in patients older than 60 years of age are particularly rare. Although surgery and radiotherapy play important roles in treatment of medulloblastoma in adults, addition of chemotherapy is controversial, especially prior to radiotherapy. CASE DESCRIPTION We present a case of a 63-year-old woman with an atypical medulloblastoma in the cerebellum and a lesion in the suprasellar area that did not appear to be a metastasis of the medulloblastoma. The patient underwent a subtotal resection of the cerebellar medulloblastoma, which was classified histologically as classic subtype and molecularly as non-Wingless/non-Sonic hedgehog subtype in World Health Organization 2016 classification. Then she underwent postoperative chemotherapy followed by radiotherapy. We administered chemotherapy to facilitate therapeutic diagnosis of the suprasellar lesion. The combination treatment resulted in the disappearance of the cerebellar medulloblastoma with treatment toxicity well tolerated. Additionally, the suprasellar lesion remains under control. CONCLUSIONS Even in adults over 60 years of age, medulloblastoma should be included in the differential diagnosis of a cerebellar mass. Chemotherapy for adult medulloblastoma has the potential to be efficacious and tolerable.

A difficult-to-treat Acom aneurysm with the combined vascular anomaly of Acom fenestration and accessory anterior cerebral artery

Background: Vascular anomaly and aneurysmal formation of an anterior communicating artery (Acom) complex has often been reported. Because of such a complicated relationship between the vascular structure and aneurysms, Acom aneurysm is one of the most difficult aneurysms to treat among other common anterior circulation aneurysms. We experienced an extremely rare and difficult-to-treat case of ruptured Acom aneurysm with the combined vascular anomaly of the Acom fenestration and an accessory anterior cerebral artery (ACA). Case Description: A 29-year-old man underwent a clipping surgery for a ruptured Acom aneurysm with an Acom fenestration and an accessory ACA. By reasons of the complicated Acom structure and a posteriorly-projecting aneurysm, the patient was operated via an interhemispheric approach, which is generally reported to provide the best operative view for all types of Acom aneurysms. However, we could not help applying a clip in the narrow working space and the limited operative view, due to the poor mobilization of Acom complex and the interruption by an accessory ACA. Conclusion: The interhemispheric approach may exceptionally have a blind area behind the Acom complex in the case of Acom aneurysms with an accessory ACA. Additionally, the aneurysms arising from the Acom fenestration strongly require neurosurgeons to take a more accurate surgical approach to obtain a direct visualization for an aneurysmal neck.

Frontotemporal epi- and subdural approach to a cavernous sinus tumor for sphenobasal vein preservation--technical case report.

In cavernous sinus (CS) surgery, venous complication may occur in some types of venous drainage. The sphenobasal vein (SBV) drains from the superficial middle cerebral vein (SMCV) to the pterygoid venous plexus at the temporal skull base. A frontotemporal epi- and interdural approach (Dolenc approach), which is one of the CS approaches, may damage the SBV’s route. We report a case of intracavernous trigeminal schwannoma that contained the SBV and discuss our modified surgical procedure that combined epi- and subdural approaches to preserve the SBV. A 64-year-old man complained of right progressive oculomotor palsy and was referred to our hospital for surgery. MR images revealed a hemorrhagic tumor in the right CS. Three-dimensional venography revealed that the SMCV drained into the pterygoid venous plexus via the SBV. After identifying the first branch of the trigeminal nerve epidurally, we incised the dura linearly along the sylvian fissure and entered the subdural space to visualize the SBV. The incision was continued to the meningeal dura of the lateral wall of the CS along the superior margin of the first branch of the trigeminal nerve, and the Parkinson’s triangle was opened from the subdural side. The tumor was grossly totally removed, and the SBV was preserved. In conclusion, a frontotemporal epi- and subdural approach to the intracavernous trigeminal schwannoma can effectively preserve the SBV.