Memory impairment caused by cerebral hematoma in the left medial temporal lobe due to ruptured posterior cerebral artery aneurysm.

BACKGROUND: Cognitive disorders, such as memory disturbances, are often observed following a subarachnoid hemorrhage. We present a very rare case where rupture of a posterior cerebral artery aneurysm caused restricted damage to the hippocampus unilaterally, and caused memory disturbances. CASE PRESENTATION: A 56-year-old, right-handed man, with a formal education history of 16 years and company employees was admitted to our hospital because of a consciousness disturbance. He was diagnosed as having a subarachnoid hemorrhage due to a left posterior cerebral artery dissecting aneurysm, and coil embolization was performed. Subsequently, he had neither motor paresis nor sensory disturbances, but he showed disorientation, and both retrograde and anterograde amnesia. Although immediate recall and remote memory were almost intact, his recent memory was moderately impaired. Both verbal and non-verbal memories were impaired. Brain computed tomography (CT) and magnetic resonance imaging (MRI) revealed a cerebral hematoma in the left temporal lobe involving the hippocampus and parahippocampal gyrus, and single-photon emission computed tomography (SPECT) demonstrated low perfusion areas in the left medial temporal lobe. CONCLUSIONS: We suggest that the memory impairment was caused by local tissue destruction of Papez's circuit in the dominant hemisphere due to the cerebral hematoma.

Clinical and angiographic characteristics of cavernous sinus dural arteriovenous fistulas manifesting as venous infarction and/or intracranial hemorrhage.

INTRODUCTION: Cavernous sinus (CS) dural arteriovenous fistulas (DAVFs) rarely cause venous infarction (VI) and/or intracranial hemorrhage (ICH) despite the presence of cortical venous drainage (CVD). The present study investigated the characteristics of CS DAVFs manifesting as VI/ICH. MATERIALS AND METHODS: Fifty-four patients treated for CS DAVFs were retrospectively studied. RESULTS: Six patients presented with VI/ICH. Two of the three patients presenting with ICH had CVD only to the superficial sylvian vein (SSV) or the deep sylvian vein (DSV). Three patients presenting with VI had multiple drainages, and angiography of these patients showed a varix on the SSV, drainage into the DSV with agenesis of the second and third segment of basal vein of Rosenthal, and thrombosis of the distal petrosal vein. CS DAVF with CVD only carries higher risk of VI/ICH than multiple drainages. Many CS DAVFs presenting with VI, especially those with drainage into the petrosal vein, have multiple drainages in the early stage. Thrombosis of the inferior and superior petrosal sinuses and superior orbital vein gradually increases pressure of the CVD, and then, VI may occur. In contrast, CS DAVFs with CVD only from the beginning, common in the patients with drainage into the SSVs and DSVs, are likely to cause ICH. CONCLUSION: Angiographic risk factors causing VI/ICH are CVD only, varix formation, agenesis of the second and third segment of basal vein of Rosenthal, and thrombosis of the superior orbital vein, lateral half of the superior petrosal sinus, and distal CVD.

Urgent stenting for patients with acute stroke due to atherosclerotic occlusive lesions of the cervical internal carotid artery.

Acute symptomatic occlusion of the cervical internal carotid artery (ICA) can be treated by intravenous administration of tissue plasminogen activator, percutaneous transluminal angioplasty, and carotid endarterectomy. Carotid artery stenting (CAS) is now indicated for cervical ICA stenosis, but the safety and the efficacy of urgent CAS have not been established. We retrospectively reviewed 10 patients treated by urgent CAS for atherosclerotic occlusive lesions of cervical ICA with acute stroke. Five patients had complete occlusions and five had near total occlusions. Five of the 10 patients had intracranial tandem occlusions. Indication for urgent CAS was determined by mismatch of diffusion-weighted and perfusion-weighted magnetic resonance imaging findings. Stents were successfully deployed in all lesions. Three of five patients with concomitant intracranial tandem occlusions were treated by additional intraarterial fibrinolysis after the CAS. Intracranial artery occlusions were completely recanalized in one patient, and partially recanalized in two by fibrinolysis. Hyperperfusion syndrome did not occur in any of the patients. A favorable outcome (modified Rankin Scale < or =1) was obtained in all of the five patients with isolated cervical ICA occlusion and one of the five patients with intracranial tandem occlusions. Urgent CAS is a safe and effective treatment in patients with isolated cervical ICA occlusion. Treatment of intracranial tandem occlusions is an issue that must be resolved.

Facial neuropathy due to axonal degeneration and microvasculitis following gamma knife surgery for vestibular schwannoma: a histological analysis. Case report.

Complete facial palsy (House-Brackmann Grade VI) developed in a 63-year-old man with a vestibular schwannoma 25 months after he had undergone two gamma knife surgeries performed 33 months apart and involving a cumulative dose of 24 Gy directed to the tumor margin at the 50% isodose line. Magnetic resonance imaging demonstrated tumor enlargement with central nonenhancement, which initially had been recognized 21 months after the second radiosurgery. Microsurgery was performed to achieve total removal of the tumor. Histological and immunohistochemical examinations of the facial nerve specimen removed from the edge of the tumor revealed a loss of axons, proliferation of Schwann cells, and microvasculitis. In this case, microvasculitis and axonal degeneration were probably the major causes of the radiation-induced facial neuropathy.

Primary epithelioid hemangioendothelioma originating in the lower petroclival region: case report.

BACKGROUND: We report the first case of primary epithelioid hemangioendothelioma (EH) originating in the lower petroclival region. CASE DESCRIPTION: A 55-year-old female presented with a 45-year history of subclinical atrophy on the right side of her tongue and a 15-year history of hoarseness. Neuroimaging revealed an expansile, homogeneously enhanced intraosseous mass with bony shell and honeycomb configuration in the petroclival region. A right far lateral transcondylar approach was utilized for subtotal removal of the tumor, which demonstrated high vascularity in the petroclival bone. Histopathological and immunohistochemical examination confirmed the diagnosis of EH. Because of the intermediate malignancy, adjuvant gamma knife radiotherapy was performed for the residual mass 5 months after surgery. CONCLUSION: EH rarely occurs in the skull base region. The appearance of surrounding bony structure and rich vascularity are important findings for the differential diagnosis. A far lateral transcondylar approach provides sufficient exposure of the jugular tubercle and lower clivus. Additional radiotherapy may be recommended for residual tumors with a high MIB-1 labeling index.