1/4. Imaging of acute bilateral paramedian thalamic and mesencephalic infarcts.Thalami and midbrain arterial supply arises from many perforating blood vessels with a complex distribution for which many variations have been described. One rare variation, named the "artery of Percheron," is a solitary arterial trunk that arises from one of the proximal segments of a posterior cerebral artery and supplies the paramedian thalami and the rostral midbrain bilaterally. Occlusion of this artery results in bilateral thalamic and mesencephalic infarctions. We describe three patients with a presumed occlusion of the artery of Percheron in whom MR imaging showed characteristic symmetrical bilateral paramedian thalamic and mesencephalic infarctions.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
2/4. Congenital cavernous angioma exhibits a progressive decrease in size after birth.CASE REPORT: We report a case of congenital intracranial cavernous angioma, which was initially found at a gestational age of 34 weeks in utero as a mass lesion associated with hydrocephalus. After birth, the patient was treated for hydrocephalus first by external drainage and then by ventricular peritoneal shunt. The natural course of the mass lesion was observed until the age of 8 months when the histopathological diagnosis confirmed the cavernous angioma after tissue was obtained by surgery. CT scans repeated monthly during this period demonstrated that the angioma continuously decreased in size. There was no evidence of hemorrhage in the angioma on serial CT scans. The histopathology revealed thrombosis of cavernous vessels with hyaloid changes in the angioma. DISCUSSION: The mechanisms of the decreasing size of the cavernous angioma have often been discussed in relation to spontaneous hemorrhages and resolution. The present case suggests a mechanism in which the spontaneous formation of a thrombus might be the dominant factor for the decrease in size. Thrombus formation may result from low perfusion due to the large size of the angioma.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
3/4. Thalamic dementia: an example of primary astroglial dystrophy of Seitelberger.Pure thalamic dementia is highly uncommon and typically demonstrates widespread loss of neurons throughout the thalamus associated with reactive gliosis. This report describes an autopsy case in which there is widespread gliosis of subcortical white matter, focal hippocampal sclerosis and a unique proliferation of protoplasmic astrocytes in the thalamus, with limited bilateral focal loss of neurons. The alterations of the protoplasmic astrocytes consist of proliferation of perivascular feet surrounding blood vessels and velate sheets which surround individual neurons. It is proposed that the astrocytic alterations, or astrocytic dystrophy, constitute the primary and critical pathologic-change, sufficiently severe to produce dementia in the presence of a relatively intact neuronal population.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |
4/4. pain and neuroma formation in Wallenberg's lateral medullary syndrome.We report a patient with a Wallenberg's lateral medullary syndrome in which pain was a prominent feature. This led to substitution of the original and correct diagnosis by that of a thalamic syndrome for which a prefrontal leucotomy was performed. The patient died some years later from a myocardial infarction and autopsy was performed. In the dorsolateral part of the medulla oblongata a cavity was found in which aberrant nerve fibres with neuroma-like formations could be seen. These fibres coursed along blood vessels, and penetrated from the surface of the medulla oblongata. On the base of the clinico-pathological correlations, it is conjectured that destruction of the lateral reticular formation cannot be the sole cause of the severe pain.- - - - - - - - - - ranking = 1keywords = vessel (Clic here for more details about this article) |