1/19. Pulmonary barotrauma-induced cerebral arterial gas embolism with spontaneous recovery: commentary on the rationale for therapeutic compression.Pulmonary barotrauma-induced cerebral arterial gas embolism (CAGE) continues to complicate compressed gas diving activities. Inadequate lung ventilation secondary to inadvertent breath holding or rapid buoyant ascent can quickly generate a critical state of lung over-pressure. Pulmonary over-pressurization may also occur as a consequence of acute and chronic pulmonary pathologies. Resulting barotrauma frequently causes structural failure within the terminal distal airway. Respiratory gases are then free to embolize the systemic circulation via the pulmonary vasculature and the left heart. The brain is a common target organ. Bubbles that enter the cerebral arteries coalesce to form columns of gas as the vascular network narrows. Small amounts of gas frequently pass directly through the cerebral circulation without occlusion. Larger columns of gas occlude regional brain blood flow, either transiently or permanently, producing a stroke-like clinical picture. In cases of spontaneous redistribution, a period of apparent recovery is frequently followed by relapse. The etiology of relapse appears to be multifactoral, and chiefly the consequence of a failure of reperfusion. Prediction of who will relapse is not possible, and any such relapse is of ominous prognostic significance. It is advisable, therefore, that CAGE patients who undergo spontaneous recovery be promptly recompressed while breathing oxygen. Therapeutic compression will serve to antagonize leukocyte-mediated ischemia-reperfusion injury; limit potential re-embolization of brain blood flow, secondary to further leakage from the original pulmonary lesion or recirculation of gas from the initial occlusive event; protect against embolic injury to other organs; aid in the resolution of component cerebral edema; reduce the likelihood of late brain infarction reported in patients who have undergone spontaneous clinical recovery; and prophylax against decompression sickness in high gas loading dives that precede accelerated ascents and omitted stage decompression.- - - - - - - - - - ranking = 1keywords = circulation (Clic here for more details about this article) |
2/19. Multimodal ultrasound assessment of cerebral hemodynamics in a patient with a diffuse cerebral angiomatosis.Recent newly developed ultrasound (US) techniques extend our ability to study the cerebral hemodynamics in patients with arteriovenous malformations (AVM) beyond the conventional cerebral blood flow velocity (CBFV) analysis. We present US data of global cerebral blood flow (CBF) and global cerebral circulation time (CCT) in a patient with a unique bihemispherial diffuse cerebral angiomatosis and compare them with 10 age-matched controls. In addition, the estimation of an US-derived global cerebral blood volume (CBV) is proposed. Duplex sonographic CBF analysis revealed 2620 mL/min in the patient and 754 /- 93 mL/min in controls. Doppler sonographic CCT was 2.9 s and 6.3 /- 1.5 s and CBV 126 mL and 79 /- 19 mL, respectively. US allows a simple, minimal invasive bedside analysis of several global hemodynamic parameters that might provide valuable additional information in patients with diffusely altered cerebral hemodynamics.- - - - - - - - - - ranking = 0.33333333333333keywords = circulation (Clic here for more details about this article) |
3/19. Primary angioplasty in cadasil.We report an acute coronary event in a young patient suffering from cerebral autosomal dominant arteriopathy with sub-cortical infarcts and leucoencephalopathy (cadasil) successfully treated by primary angioplasty and direct stenting. Coronary involvement and pathophysiology of this genetic disorder is discussed.- - - - - - - - - - ranking = 0.0058294201325252keywords = coronary (Clic here for more details about this article) |
4/19. Multifocal varicella-zoster virus vasculopathy without rash.A 51-year-old woman with crest syndrome (calcinosis, Raynaud phenomenon, esophageal dysmotility, sclerodactyly, and telangiectasia) developed stepwise progressive focal neurological deficits without zoster rash. Multifocal ischemic infarcts were seen on magnetic resonance imaging, and cerebral angiography revealed focal stenosis of arteries affecting the intracranial circulation. A brain biopsy was nondiagnostic. Virological etiology of the disease was verified by the detection of varicella-zoster virus antibody in cerebrospinal fluid and by reduced serum-cerebrospinal fluid varicella-zoster virus IgG ratios (compared with normally high ratios of total IgG and albumin). Treatment with intravenous acyclovir stabilized but did not significantly improve her neurological deficits.- - - - - - - - - - ranking = 0.33333333333333keywords = circulation (Clic here for more details about this article) |
5/19. sinus pericranii: radiological and etiopathological considerations. Case report.sinus pericranii is a rare vascular anomaly involving an abnormal communication between the extracranial and intracranial circulations. A case of frontal sinus pericranii is presented which appeared to be a posttraumatic sinus because it developed 2 years after a cranial injury. However, the presence of vascular endothelium in the pathological examination and its association with a vascular anomaly (persistent trigeminal artery) suggested a congenital origin. The lesion, pericranial blood sinuses, and bone were totally removed. The computerized tomography, angiography, and magnetic resonance imaging findings are presented. The literature is reviewed and the pathogenesis of sinus pericranii is discussed.- - - - - - - - - - ranking = 0.33333333333333keywords = circulation (Clic here for more details about this article) |
6/19. Inconspicuous visual field defect in anterior choroidal artery territory infarction.We describe a patient with a right anterior choroidal artery territory infarction and an inconspicuous left visual defect. The anterior choroidal artery is a unique artery of the cerebral circulation. The occlusion of this artery can result in dysfunction of motor, sensory, and visual systems with only rare involvement of higher cortical function. Among symptoms reported, visual abnormalities are the most variable and the least common. However, the visual field abnormality may be overlooked and the incidence underestimated since some patients may not be aware of the problem until uncovered by formal visual field testing.- - - - - - - - - - ranking = 0.33333333333333keywords = circulation (Clic here for more details about this article) |
7/19. Retinal manifestations in fibromuscular dysplasia.fibromuscular dysplasia of the arteries (FMD) is a segmental angiopathy which may produce obstruction of the carotid, cerebral, renal, mesenteric, coronary or iliac arteries. Except for lesions related to arterial hypertension, retinal manifestations have not yet been reported. This paper describes the case of a 10-year-old boy with progressive deafness, a history of an unexplained stroke and progressive occlusions of the retinal arterioles in the fundus periphery. This resulted in retinal neovascularization and recurrent retinal and vitreous hemorrhages. Despite repeated photo- and cryocoagulation the eyes progressed to a tractional retinal detachment which was successfully treated by vitrectomy and scleral buckling. The diagnosis of FMD was made on the basis of a histopathological examination of a temporal artery biopsy. The child also presented an asymptomatic but severe aneurysmal dilatation of the aorta and CT scan and MRI showed dilated cerebral arteries. The father of our patient had died at the age of 27 years either from myocardial infarction or rupture of a dissecting aortic aneurysm. He was highly myopic and had lost one eye from retinal detachment. The younger brother of our patient also presents aneurysmal dilatation of the aorta and tortuous cerebral vessels. Ocular examination is still normal. The findings in this family are compatible with an autosomal dominant inheritance with variable expression.- - - - - - - - - - ranking = 0.0058294201325252keywords = coronary (Clic here for more details about this article) |
8/19. Intracranial vertebral endarterectomy.Intracranial vertebral endarterectomy was performed on six patients with vertebrobasilar insufficiency in whom medical therapy failed. The patients underwent operations for stenotic plaque in the intracranial vertebral artery with the opposite vertebral artery being occluded, hypoplastic, or severely stenosed. In four of the patients, the stenosis was mainly proximal to the posterior inferior cerebellar artery (pica). In this group, after endarterectomy, the vertebral artery was patent in two patients, and their symptoms resolved; in one patient the endarterectomy occluded, but the patient's symptoms improved; and in one patient the endarterectomy was unsuccessful, and he continued to have symptoms. In one patient, the plaque was at the origin of the pica. The operation appeared technically to be successful, but the patient developed a cerebellar infarction and died. In one patient the stenosis was distal to the pica. During endarterectomy, the plaque was found to invade the posterior wall of the vertebral artery. The vertebral artery was ligated, and the patient developed a Wallenburg syndrome. The results of superficial temporal artery to superior cerebellar artery anastomosis are better than those for intracranial vertebral endarterectomy for patients with symptomatic intracranial vertebral artery stenosis. The use of intracranial vertebral endarterectomy should be limited to patients who have disabling symptoms despite medical therapy, a focal lesion proximal to the pica, and a patent posterior circulation collateral or bypass.- - - - - - - - - - ranking = 0.33333333333333keywords = circulation (Clic here for more details about this article) |
9/19. Tandem bypass: occipital artery to posterior inferior cerebellar artery side-to-side anastomosis and occipital artery to anterior inferior cerebellar artery end-to-side anastomosis--a case report.A unique example of posterior fossa revascularization is presented. A tandem bypass was performed by anastomosing the midoccipital artery to the posterior inferior cerebellar artery in a side-to-side fashion followed by anastomosis of the distal occipital artery to the anterior inferior cerebellar artery in an end-to-side fashion. The operation was designed to revascularize two separate vascular territories that were isolated in a patient thought to have an extremely compromised posterior circulation. The patient is doing well and is asymptomatic 3 years postoperatively.- - - - - - - - - - ranking = 0.33333333333333keywords = circulation (Clic here for more details about this article) |
10/19. Dynamic CT brain scanning in the haemodynamic evaluation of cerebral arterial occlusive disease.Dynamic cerebral CT scanning (DCT) was used to quantitatively analyse the haemodynamic effects of extracranial and intracranial arterial occlusive lesions in 17 patients with TIA's or minor cerebral infarcts. Using DCT and gamma variate curve fitting, mean transit times were determined for the terminal internal carotid arteries, middle cerebral arteries and middle cerebral-supplied Sylvian cortex at the level of the circle of willis. Six patients were studied sequentially, four before and after transcranial bypass surgery. No arterial or tissue delays were found in patients without haemodynamic arterial lesions or cortical infarcts. Seven of nine patients with haemodynamic, extracranial carotid lesions showed ipsilateral delays in arterial or tissue transit times. Tissue delays usually correlated with CT or clinical evidence of infarction. Improved haemodynamics in patients re-studied correlated with the effects of surgery or clinical recovery. DCT has several important limitations but has the potential to provide additional haemodynamic information about the cerebral circulation in selected patients with cerebral arterial occlusive disease.- - - - - - - - - - ranking = 0.33333333333333keywords = circulation (Clic here for more details about this article) |
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