Surgical treatment of spinal extradural arteriovenous fistula with parenchymal drainage: report on 5 cases.

BACKGROUND AND IMPORTANCE: Spinal extradural arteriovenous fistula (SEDAVF) with parenchymal drainage (type A) is a rare clinical entity that causes venous congestive myelopathy. Treatment includes endovascular and open microsurgical interventions. We reviewed the clinical records of patients treated for a type A SEDAVF to evaluate the feasibility of our treatment strategy. CLINICAL PRESENTATION: Between 2004 and 2010, 5 patients with a type A SEDAVF were treated at our institutes (4 men and 1 woman; mean age, 60 years). We performed endovascular transvenous embolization (TVE) when lesions were accessible transvenously; otherwise, microsurgical perimedullary drainer occlusion was performed. Follow-up ranged from 23 to 94 months (mean, 45.8 months). One patient was treated with TVE, and the remaining 4 were treated with microsurgical drainer occlusion. After a simple intradural drainer occlusion, an epidural venous lake was completely thrombosed in 2 patients. In 1 patient, postoperative angiography revealed that a part of the epidural component had persisted; however, the patient has been asymptomatic. In the remaining case with multiple intradural draining veins, sole drainer occlusion was not sufficient. A second surgery was required to meticulously coagulate the venous lake. As a consequence, parenchymal drainers disappeared. Overall, all patients stabilized or improved neurologically and experienced no recurrence. CONCLUSION: To treat a type A SEDAVF, either TVE or microsurgical intradural drainer occlusion can be used for satisfactory long-term results with minimal surgical risks. For a case with multiple intradural draining veins, detachment of the venous lake should be considered.

Comparison of large intrasylvian and subpial hematomas caused by rupture of middle cerebral artery aneurysm.

The clinical characteristics of intrasylvian and subpial hematomas caused by rupture of middle cerebral artery (MCA) aneurysm were examined in 86 patients admitted to our department with subarachnoid hemorrhage (SAH) caused by ruptured MCA aneurysms. A retrospective study of 26 patients with a large hematoma associated with SAH treated surgically within 48 hours evaluated clinical grade at admission, secondary development of cerebral swelling, ratio of hematoma removal, and incidence of symptomatic vasospasm. Clinical grade on admission, age, and sex showed no significant differences. Ratio of cerebral swelling against the initial hematoma volume (p = 0.005), and incidence of symptomatic vasospasm (p = 0.041) were significantly lower, and the ratio of hematoma was significantly higher (p = 0.01) in the subpial hematoma group. Removal of hematoma was more difficult and symptomatic vasospasm was more frequent in the intrasylvian hematoma group. The clinical features of subpial and intrasylvian hematomas caused by rupture of MCA aneurysm should be considered for the better management of associated SAH.

Evolution of vestibular schwannoma after removal of epidermoid cyst of the same location: case report.

A 71-year-old man presented with vestibular schwannoma manifesting as hearing disturbance and truncal ataxia 16 years after removal of a cerebellopontine angle (CPA) epidermoid cyst, and located adjacent to the remnant lesion. The patient first presented with a 6-month history of right trigeminal neuralgia. Neuroimaging demonstrated a right CPA lesion, suggestive of an epidermoid cyst. Right lateral suboccipital craniotomy was performed and the histological diagnosis was epidermoid cyst. A small lesion remained, but the symptoms were relieved. Sixteen years later, the patient presented with right auditory disturbance, vertigo, and truncal ataxia. Magnetic resonance imaging revealed a multiple cystic mass adjacent to the remnant epidermoid cyst in the right CPA. The lesion was removed and the histological diagnosis was vestibular schwannoma associated with the epidermoid cyst. The irritative effect of the remnant epidermoid cyst or surgical procedures may have caused the vestibular schwannoma, but no evidence of the evolution of the different types of tumors was found.

Adult traumatic leptomeningeal cyst: case report.

A 60-year-old man presented with a traumatic leptomeningeal cyst manifesting as local tenderness in the right parietal region and local headache 2 years after head injury. Magnetic resonance imaging showed a small arachnoid cyst under bone defect. Dural and bone plasty were performed. Intraoperative examination found small and round defects of the dura and bone. Progressive headache was relieved after the surgery. This rare case of adult posttraumatic leptomeningeal cyst occurred within an unusually short period after trauma, and was associated with a small and round bone defect and small dural defect usually characteristic of congenital arachnoid cyst.

Ruptured pseudoaneurysm following Gamma Knife surgery for a vestibular schwannoma.

A 75-year-old woman underwent Gamma Knife surgery (GKS) for a vestibular schwannoma. Eight years after GKS, she suffered sudden onset of headache. Computed tomography revealed diffuse subarachnoid hemorrhage around the cisterns of the posterior fossa. Right vertebral artery angiography showed an aneurysm arising from the lateral pontomedullary segment of the left anterior inferior cerebellar artery. The aneurysm was not located at a branching site. Trapping of the distal anterior inferior cerebellar artery aneurysm was performed, and the aneurysm was removed. The pathological features of this aneurysm are discussed. This aneurysm was diagnosed as a pseudoaneurysm pathologically. This is the first report of aneurysm formation with pathological findings following GKS for a vestibular schwannoma.

A case of multiple pial arteriovenous fistulas associated with dural arteriovenous fistula.

Pial arteriovenous fistulas (AVFs) are known as rare cerebrovascular lesions. They are composed of >/= 1 arterial feeding vessels and a single draining vein that usually has high perfusion pressure and generally occur in infants. Cases involving adults are very rare and the developmental mechanisms and natural history of these lesions remain unknown. The authors present a case of multiple pial AVFs in an adult in whom the lesions developed after radiosurgical treatment of dural AVFs. Direct disconnection of pial arterial supplies was performed, and the abnormal shunts were successfully eliminated. The authors report the clinical course of this case and discuss the characteristics of and treatment strategy for multiple pial AVFs, reviewing the published literature.

Medulloblastoma with extensive nodularity: single photon emission CT study with iodine-123 metaiodobenzylguanidine.

We present the case of an infant with medulloblastoma with extensive nodularity, which had been called cerebellar neuroblastoma. MR imaging clearly revealed a nodular enhancement, which appeared as a grape-like lesion. Single photon emission CT revealed markedly high iodine-123 metaiodobenzylguanidine uptake in the enhancing tumor. Iodine-123 metaiodobenzylguanidine single photon emission CT may be useful in the diagnosis of medulloblastoma with extensive nodularity, which has been considered to be a subgroup of medulloblastoma with extensive neuronal differentiation.

Anterior paraclinoid aneurysms.

OBJECT: The characteristics of a previously unclassified paraclinoid aneurysm arising from the anterolateral (dorsal) wall of the proximal internal carotid artery were retrospectively analyzed in seven patients (five women and two men) who were treated surgically for an aneurysm in this unusual location. METHODS: One patient presented with subarachnoid hemorrhage (SAH) caused by rupture of this aneurysm. The lesions were found incidentally (five cases) or during investigation of SAH due to another aneurysm (one case). There was a female predominance in this series; all female patients harbored multiple aneurysms. All patients underwent surgery. Removal of the anterior clinoid process was necessary because the proximal neck of the aneurysm was closely adjacent to the dural ring. CONCLUSIONS: This special group of aneurysms is very rare, is located exclusively in the intradural space, and carries the risk of SAH. The results of surgical treatment for this aneurysm are quite satisfactory.