Carotid arterial supply of the feline brain. Applications to the study of regional cerebral ischemia.
(25/215)
A study of the supply to the feline brain by the carotid-middle cerebral arteries was conducted using in vivo transcardiac injection with a mixture of micropaque and carbon black. Modifications in the filling pattern of the arterial vessels were visualized following short-term occlusion of a middle cerebral artery. A modified surgical method to induce occlusion of the M-l segment of the middle cerebral artery is also described. (+info)
External carotid artery shunting during carotid endarterectomy: an alternative for cerebral protection?
(26/215)
OBJECTIVES: to assess the application of external carotid artery (ECA) shunting in cerebral protection during carotid endarterectomy (CEA). DESIGN: prospective study. MATERIALS AND METHODS: the study comprised 137 consecutive patients who underwent CEA under locoregional anaesthesia. Transcranial Doppler was used to monitor the mean velocity of the middle cerebral artery (mv-MCA): (1) before carotid clamping; (2) after clamping both the common and external carotid arteries; (3) after clamping the internal carotid artery alone ("ECA test"). The decision to shunt was based on the occurrence of neurological deficit during carotid clamping. If the ECA test revealed mv-MCA approaching the pre-clamping values ECA shunting was used, whereas the remaining patients in need of a shunt had a standard internal carotid artery (ICA) shunt. RESULTS: shunting was necessary in 12/137 cases (9%). The ECA test indicated that in four cases - 3% of the whole series or 33% of the shunted cases. In these four patients ECA shunting reversed the neurological deficit, and CEA was successfully performed without any complications. CONCLUSIONS: ECA shunting could be considered as an alternative to standard ICA shunting. Suitable cases can be identified on the basis of the ECA test. (+info)
Endarterectomy for narrowing of the external carotid artery in a patient who underwent extracranial-intracranial bypass for occlusion of the internal carotid artery--case report.
(27/215)
A 56-year-old man had undergone extracranial-intracranial (EC-IC) bypass surgery for occlusion of the right internal carotid artery. Six years later, he complained of transient episodes of numbness in the left arm, occurring periodically over the previous 3 months. Neuroimaging showed the right external carotid artery was severely narrowed and cerebral blood flow (CBF) was diffusely low. Endarterectomy of the right external carotid artery was performed. Postoperative CBF was markedly improved, suggesting that EC-IC bypass became effective again by endarterectomy of a parent artery. (+info)
Radionuclide cerebral angiographic evaluation of a diploic extracranial meningioma: case report.
(28/215)
A case of a diploic extracranial meningioma whose true vascularity was more significantly defined by radionuclide angiography than by selective contrast angiography is presented. The radionuclide angiogram clearly demonstrated large venous channels draining the tumor. (+info)
Subclavian steal syndrome: report of 28 cases.
(29/215)
OBJECTIVE: To study the experience in the treatment of subclavian steal syndrome (SSS) and the relation between SSS and the damage of brain. METHODS: In 28 patients with SSS, 23 were operated on. They complained of vertigo, TIA, and claudication of arms. One patient suffered from severe stem ischemia spasm. All the patients were subjected to subtraction angiography. Fifteen of them showed retrograde flow in the vertebral arteries. Transcranial Doppler revealed retrograde blood flow in 8 patients. Single photon emission tomography showed inadequate blood supply to the brain with affected subclavian arteries in 4 patients. Carotid-subclavian arterial bypass was performed in 16 patients, axilloauxillary bypass in 3, PTA in 1, and aorta-carotid graft bypass in 3. RESULTS: 13 patients (13/23) had their cerebrovascular symptoms relieved. Transcranial Doppler and emission tomography after operation showed nothing abnormal. CONCLUSION: SSS is harmful and the patients should be closely monitored by means of transcranial Doppler and emission tomography. (+info)
Congenital absence of the external carotid artery: atherosclerosis without a bifurcation.
(30/215)
We report the case of a patient with congenital absence of the external carotid artery in whom we performed a carotid endarterectomy. The radiographic features and operative findings are presented. Four similar cases previously reported in the literature are reviewed. A comment on the pathophysiology of atherosclerosis at the carotid bulb in the absence of a bifurcation and a brief discussion on the possible embryologic explanation of this anomaly are discussed. (+info)
Grey matter and white matter ischemic damage is reduced by the competitive AMPA receptor antagonist, SPD 502.
(31/215)
Protection of both grey and white matter is important for improvement in stroke outcome. In the present study the ability of a competitive alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) antagonist to protect axons, oligodendrocytes, and neuronal perikarya, was examined in a rodent model of transient focal cerebral ischemia. SPD 502 (8-methyl-5-(4-( -dimethylsulfamoyl)phenyl)-6,7,8,9-tetrahydro-1H-pyrrolo[3,2h]-isoquinoline-2,3-d ione-3-o(4-hydroxybutyricacid-2-yl)oxime) was administered as an intravenous bolus (16 mg/kg) 15 minutes before transient (3-hour) middle cerebral artery (MCA) occlusion, followed by an intravenous infusion (16 mg kg(-1) hr(-1)) of the drug for 4 hours. Twenty-one hours after ischemia, axonal damage was reduced by 45% (P = 0.006) in the SPD 502-treated group compared with the vehicle. The anatomic extent of ischemically damaged oligodendrocytes, determined by Tau1 immunoreactivity, was reduced in the cerebral cortex by 53% (P = 0.024) in SPD 502-treated rats compared with vehicle-treated rats, but there was minimal effect in the subcortex. The volume of neuronal perikaryal damage after MCA occlusion was significantly reduced by SPD 502 in the cerebral cortex (by 68%; P = 0.005), but there was minimal change in the subcortex with drug treatment. The AMPA receptor antagonist significantly reduced the anatomic extent of lipid peroxidation (assessed as the volume of 4-hydroxynonenol immunoreactivity), and this may have contributed to its ability to protect multiple cell types in ischemia. The data demonstrate that AMPA blockade protects both grey and white matter from damage induced by transient focal ischemia. (+info)
Giant cell reparative granuloma of the temporal bone: neuroradiological and immunohistochemical findings.
(32/215)
A 38-year-old man presented with a giant cell reparative granuloma (GCRG) of the left temporal bone. Computed tomography showed a osteolytic middle cranial mass lesion. Magnetic resonance (MR) imaging showed the lesion as low intensity with heterogeneous enhancement by gadolinium on the T1-weighted images, and extremely low intensity on the T2-weighted images. Angiography showed the lesion as highly vascular and fed by branches of the left external carotid artery. After preoperative embolization, gross total removal of the tumor was performed. The postoperative course was uneventful and no evidence of recurrence has been found for more than 4 years. Histological examination revealed GCRG with multinucleated giant cells in the fibrous background, abundant collagen bundles, hemosiderin deposits, and trabeculae of reactive bone. Some of the mononuclear stromal cells and almost all of the giant cells were positive for CD68, suggesting histiocytic differentiation. These histological features reflect the marked decrease in signal intensity on T2-weighted MR images. (+info)