Diffusion tensor (DT) imaging provides quantitative information about the magnitude and the directionality (anisotropy) of water diffusion in vivo and can detect pathologic changes in brain ischemia. This study tried to detect ischemic brain damage using DT imaging in patients with symptomatic chronic major cerebral artery occlusive disease. DT imaging was performed using a 3.0 Tesla magnetic resonance (MR) scanner in 50 patients with unilateral internal carotid artery or middle cerebral artery stenosis or occlusion, who had no obvious infarct lesions on conventional MR imaging. Thirty-three patients underwent DT imaging before and after vascular reconstruction surgery. Fractional anisotropy (FA) was calculated in the middle cerebral artery territory. Preoperative FA values in the ipsilateral side were significantly lower than those in the contralateral side. After surgery, the FA value was significantly increased. DT imaging may indicate ischemic brain damage, not visualized by conventional MR imaging, in patients with major cerebral artery occlusive disease.
Methods for preservation of the sylvian veins in the transsylvian approach have not been established because of the considerable variations. This study attempted to classify the sylvian veins to facilitate systematic dissection of the sylvian fissure for sylvian veins to be preserved. The operative anatomy of the sylvian vein was examined in 82 hemispheres. The type of drainage and the pattern of branching were investigated. The superficial sylvian vein (SSV) was classified into three types according to the number of stems draining into the dural sinus on the inner surface of the sphenoid bone: The SSV was absent or hypoplastic in eight cases, the SSV was single in 38 cases, and the SSV was double in 36 cases. The SSV drained into neither the sphenoparietal sinus nor the cavernous sinus in nine cases. An anastomosis between the SSV and the deep middle cerebral vein (DMCV) was observed in 42 cases. The frontobasal bridging vein (FBBV) drained into the sphenoparietal sinus in 47 cases. The type of connection was further subdivided into four types according to the connections with the DMCV and FBBV. The venous anatomy of sylvian fissure indicates that dissection (skeletonization) of the main stem of sylvian veins from the temporal lobe should be performed to preserve the tributaries from the frontal lobe.
Four patients presented with familial intracranial aneurysms and familial moyamoya disease, including one patient with both familial intracranial aneurysm and moyamoya disease. Basilar bifurcation aneurysms were present in two patients, moyamoya disease in one, and both basilar bifurcation aneurysm and moyamoya disease in one. These events are most likely to arise from different genetic abnormalities associated with basilar bifurcation aneurysm and moyamoya disease.
A 69-year-old woman presented with headache and short memory disturbance. Computed tomography (CT) demonstrated a small cystic mass lesion in the left temporal lobe. CT and magnetic resonance imaging showed that this lesion enlarged with repeated hemorrhages, associated with progressive amnesia and headache during 3 years follow up. Surgery demonstrated a well-demarcated hard mass lesion in the medial temporal lobe through a transcortical approach after opening left sylvian fissure. The lesion was located entirely in the brain parenchyma and was removed en-bloc after cutting some capillary-like vessels on the capsule. The histological diagnosis was encapsulated old hematoma. The histological findings suggested that expansion of the lesion was due to multiple bleedings from the sinusoidal vessels in the capsule fed by small feeding arteries. The mass effect due to the expansion of the encapsulated hematoma caused progressive short-term amnesia and headache, which were completely resolved by the surgical removal.
A 42-year-old man suffered subarachnoid hemorrhage manifesting as sudden severe headache one month before admission. On admission, his headache had subsided and he had no neurological deficits. Cerebral angiography demonstrated an aneurysm originating from the bifurcation of the right middle cerebral artery. The aneurysm was irregular, with a snowman-like shape. Neck clipping of the aneurysm was carried out through a right pterional approach. Intraoperatively, a red, pulsating sac mimicking a blood clot (the snowman's “head”) was located over the yellowish, thick-walled portion of the aneurysm. Exploration around the aneurysm detached the red sac from the thick-walled portion of the aneurysm. There was a small tear in the apex of the thick-walled aneurysm sac. A Sugita clip was applied to the neck of the true aneurysm. The postoperative course was uneventful and he was discharged one month later without neurological deficits. Histological examination of the red-colored sac showed the features of pseudoaneurysm. The red sac may have been a pseudoaneurysm covering the rupture site of the true aneurysm.
Hereditary hemorrhagic telangiectasia (HHT) is easily overlooked in patients with central nervous system (CNS) lesions. Our clinical experience of three patients with CNS lesions associated with HHT stresses the importance of considering HHT. A 23-year-old male presented with consciousness disturbance and right hemiparesis. Emergency cerebral digital subtraction angiography revealed occlusion of the left middle cerebral artery and the left anterior cerebral artery. Pulmonary arteriography showed three pulmonary arteriovenous malformations (AVMs). A 62-year-old male presented with consciousness disturbance and sensory aphasia. Magnetic resonance imaging revealed a ring-enhanced lesion in the left temporal lobe which was removed by left frontotemporal craniotomy. The diagnosis was brain abscess. Chest computed tomography (CT) revealed two pulmonary AVMs. A 32-year-old female presented with progressive mild weakness in her left hand. Initial CT showed subcortical hemorrhage in the right frontal lobe. Cerebral angiography revealed no vascular malformations, but chest CT disclosed five pulmonary AVMs. All three patients had a family history of HHT. The possibility of HHT is important to consider in patients with cerebrovascular disease (CVD) or brain abscess to prevent complications, not only in the patients but also their blood relatives. Therefore, the medical and family history of patients with CVD or brain abscess should be investigated and HHT should be considered during the physical examination.
A 47-year-old woman presented with headache and left homonymous hemianopsia. T1-weighted magnetic resonance (MR) imaging with contrast medium showed a mass lesion with ring-like enhancement in the right temporo-occipital lobe. The patient underwent surgery, focal irradiation, and chemotherapy. The histological diagnosis was glioblastoma. Four months after the operation, the patient again developed headache and left homonymous hemianopsia in addition to vomiting and mild left hemiparesis. MR imaging showed recurrence of the tumor and hydrocephalus. The patient underwent a second craniotomy and placement of a ventriculoperitoneal shunt. Intraoperative findings revealed that the transverse-sigmoid sinus was occluded by tumor invasion. The patient died of intraventricular dissemination 2 months after the second operation. Autopsy revealed metastases in the spleen and lungs. Glioblastoma with metastases to the spleen is very rare. The prognosis for patients is poor. Excessive therapy should not be used for patients with extracranial metastases from glioblastoma.
A 42-year-old woman with locally advanced breast cancer developed headache just after completing adjuvant chemotherapy. Magnetic resonance imaging revealed a mass located in the left subthalamic nucleus (STN) and involving the posterior part of the thalamus and the hypothalamus. The patient refused a radiologically guided biopsy and gamma knife treatment was not financially possible. Palliative whole brain radiotherapy with hormonal therapy was administered. The patient gained 19 kg body weight during 4 months follow up because of hyperphagia. This solitary tumor, either a breast cancer metastasis or a primary tumor, involving the STN is extremely unusual.
Cerebral blood flow and metabolism were evaluated in an adult with symptomatic intractable epilepsy and Sturge-Weber syndrome (SWS) manifesting as angiomas in the left cerebral hemisphere. 99mTc-ethylcysteinate dimer single photon emission computed tomography detected reduced blood flow in the entire left cerebral hemisphere, and [18F]fluorodeoxyglucose positron emission tomography (PET) showed decreased glucose metabolism in the left cerebral hemisphere. These findings indicated hypofunction of the left cerebral hemisphere, which caused the right hemiparesis. 11C-methionine (11C-Met) PET revealed high 11C-Met accumulation in the angiomas in the left cerebral hemisphere. Immunostaining for glial fibrillary acidic protein showed positive reaction in the lesions. Gliosis is a likely mechanism for the 11C-Met accumulation, which is possibly associated with progressive calcification in the angiomas and retarded growth of patients with SWS occurring over many years.
Patients who undergo open carpal tunnel surgery frequently complain of the postoperative cosmetic appearance at the site of the incision on the palm. This problem occurs as a result of excessive scar formation, and the long incision. A double mini skin incision, each 1 cm long, was used in the surgical treatment of carpal tunnel syndrome. The transverse carpal ligament was easily sectioned. Postoperatively healing was good with no excessive scar formation.