Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0022116 (ischemia)
 91,303 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The response of cerebrospinal fluid pressure to increased arterial carbon dioxide tension was examined in 5 control dogs and 7 dogs with experimental communicating hydrocephalus. The cerebrospinal fluid pressure in control animals only rose to 35 mm Hg after elevation of the arterial CO2 tension. In dogs with experimental communicating hydrocephalus, however, a significant rise of intracranial pressure to 60 mm Hg can be demonstrated. This is accompained by a marked simultaneous decrease of cerebral perfusion pressure in hydrocephalic animals. Progression of communicating hydrocephalus can be explained as damage to the cerebral tissue by increased intracranial pressure waves and by ischemia due to low cerebral perfusion pressure.
 ...
PMID:[Alterations of cerebrospinal fluid pressure in experimental communicating hydrocephalus. Response of CSF-pressure to increased CO2-tension (author's transl)]. 2 69

Paget's disease of the skull is the main cause of basilar artery syndromes in the adult. They may cause various neurological symptoms, including signs of ischemia of the spinal cord or medulla, or involvement of the cranial nerves and brain stem and, also, distant symptoms due to hydrocephalus, with various mental disorders including transient, recurrent, coma. The authors discuss 30 cases found in the world literature and 6 unreported personal cases, study the clinical symptoms of these cases of basilar artery compression due to Paget's disease, and the methods of neuro-radiological investigation, and emphasize the interest, in severe forms, of early surgical decompression before the stage of severe neurological complications. Regular supervision of patients with Pagets disease is thus essential to detect at an early stage, decompensation of basilar artery insufficiency in Paget's disease. In late forms, calcitonin may be indicated.
 ...
PMID:[Neurologic complications of pagetic basilar impressions and their surgical treatment]. 16 40

Subcortical arteriosclerotic encephalopathy, a chronic vascular dementia with hydrocephalus, was characterized pathologically in five patients by severe thickening of small vessels and by diffuse regions of white matter loss with gliosis. Lacunar infarcts were also present. The clinical picture in 11 patients was characterized by: (1) persistent hypertension and systemic vascular disease; (2) acute strokes; (3) subacute accumulation of focal neurologic symptoms and signs over weeks to months; (4) long plateau periods; (5) lengthy clinical course; (6) dementia; (7) prominent motor signs and pseudobulbar palsy and; (8) hydrocephalus. The pathogenesis of subcortical arteriosclerotic encephalopathy is unknown; possible mechanisms include diffuse ischemia and fluid transudation with subsequent gliosis related to subacute hypertensive encephalopathy.
 ...
PMID:Clinical features of subcortical arteriosclerotic encephalopathy (Binswanger disease). 56 79

During the past few years CT has emerged as an unsurpassed diagnostic modality in cerebrovascular disease. CT is of limited value in TIA, but reveals a wide variety of findings in completed infarcts. Ischemic, petechial, and hemorrhagic infarcts can be distinguished. Contrast enhancement, varying with the age of the infarct, is frequent. Also the general density of the infarct varies with time. Differential diagnosis, primarily infarct vs tumor, is made by angiography or by followup CT scans. Saccular aneurysms are directly demonstrable by CT if larger than 0.5 cm in diameter. Sequelae of ruptured aneurysm--hematoma, hydrocephalus, ischemia--are consistently visible. This generally also applies to arteriovenous malformations. Angiography is necessary to clarify anatomical details of aneurysms and vascular malformations, and is often indispensable for differential diagnosis.
 ...
PMID:CT diagnosis of cerebrovascular disorders--a review. 71 88

To delineate the pathophysiology of periventricular hemodynamics in normal pressure hydrocephalus, we performed quantitative and three-dimensional measurements of cerebral blood flow (CBF) by using xenon-enhanced computed tomographic scans. Measurements were made on 7 patients in whom normal pressure hydrocephalus after subarachnoid hemorrhage had been confirmed by clinical improvement after shunting. We compared mean CBF values in the white matter and cortex of the frontal, temporal, parietal, and occipital lobes and in the thalamus before and after shunting, with an evaluation of dementia and the extent of ventricular dilation and periventricular lucency on computed tomographic scans. CBF returned to within normal limits in the white matter of the frontal and temporoparieto-occipital lobes. CBF restoration closely correlated with clinical improvement and reduction in ventricular dilation and periventricular lucency. We speculate that ischemia occurs initially in the periventricular white matter as a result of diffused cerebrospinal fluid and then extends of the cortex and to the thalamus, causing a "misery perfusion" state with neuronal dysfunction. Incomplete improvement of dementia and CBF in the cortex and thalamus may be explained by preexisting arteriosclerosis in aged patients, coexisting brain damage caused by subarachnoid hemorrhage and subsequent surgical insult in aneurysm patients, and delayed recovery of cortical function that has been secondarily impaired by the periventricular lesions.
 ...
PMID:Significance of periventricular hemodynamics in normal pressure hydrocephalus. 158 81

Common intracranial complications following head injury are meningitis, usually associated with a basilar skull fracture or open-depressed skull fracture; delayed hematoma; hydrocephalus; and vascular injuries. Prophylactic antibiotics are not recommended for the management of basilar skull fractures. The best means of preventing infection from open-depressed skull fractures is operative debridement and thorough irrigation, though recent evidence suggests that select cases can be safely managed without operation. Serial CT scans should be obtained in severely head-injured patients to identify delayed hematomas. CT and MRI scans obtained several weeks or months after severe head injury frequently reveal enlarged ventricles, though only a small percentage of these patients have clinical hydrocephalus. Those that do, often benefit from a shunt. Vascular injuries frequently are not detected until ischemic symptoms develop hours or days after the injury. Recommended treatment for intimal tears or dissection is full anticoagulation, but in those with cerebral contusions or other intracranial lesions, this may present an unacceptable risk for intracranial hemorrhage. Pulmonary infections frequently occur following head injury, and can be associated with admission to the ICU and intubation. A large percentage of these infections are caused by enteric gram-negative organisms, and aggressive treatment with appropriate antibiotics is necessary. Aspiration of gastric contents is common in head-injured patients and is frequently complicated by bacterial superinfection. The routine use of antacids and H2 blocking agents leads to bacterial colonization of the stomach with anaerobes and gram-negative aerobes. Thus, empiric therapy for aspiration pneumonia should include clindamycin. Sinusitis is a frequent cause of fever and leukocytosis in patients with nasotracheal or nasogastric tubes in place for several days and often subsides spontaneously with removal of the tubes. Pulmonary edema is often caused by excessive fluid administration during resuscitation of these patients, and can be avoided by monitoring central venous pressures. Pulmonary edema may also be caused by ARDS, excessive catecholamine release, or primary cardiac failure. Most of these patients will benefit from early intubation and PEEP. Pulmonary emboli most often originate from deep venous thrombi, and there is increasing evidence that prophylaxis with low-dose heparin and pulsating boots can significantly reduce the incidence of both complications. Erosive gastritis is found in the majority of severely head-injured patients and may be due to ischemia of the gastric mucosa as well as gastric hyperacidity.(ABSTRACT TRUNCATED AT 400 WORDS)
 ...
PMID:Complications of head injury and their therapy. 182 50

Previous studies of cerebral oxygen metabolism and extraction in patients with subarachnoid hemorrhage (SAH) have yielded conflicting results. We used positron emission tomography (PET) to measure the regional cerebral metabolic rate for oxygen (rCMRO2), oxygen extraction fraction (rOEF), and cerebral blood flow (rCBF) 16 times in 11 patients with aneurysmal SAH. All studies were performed preoperatively; no patient had hydrocephalus or intracerebral hematoma on brain CT. Eight patients with no arteriographic vasospasm who were studied on days 1-4 post-SAH had a significant 25% reduction in global CMRO2 compared to age-matched controls, and no significant change in global OEF, suggesting a primary reduction in CMRO2 caused by SAH. Four patients studied seven times during arteriographic vasospasm had significantly increased rOEF with unchanged CMRO2 in arterial territories affected by arteriographic vasospasm compared to territories without vasospasm, indicative of cerebral ischemia without infarction. No brain regions studied with PET were infarcted on follow-up CT. We conclude that the initial aneurysm rupture produces a primary reduction in CMRO2, and that subsequent vasospasm causes ischemia.
 ...
PMID:Cerebral oxygen metabolism after aneurysmal subarachnoid hemorrhage. 187 16

Results of subarachnoid hemorrhage (SAH) in the acute phase are represented by the direct threat of vasospasm. The first step still is to recognise SAH, so that all misleading clinical aspects of arterial aneurysm rupture do not misguide, or even fail to do the right diagnosis. If so, rebleeding still remains a real danger. Among biological patterns, hyponatremia is an important factor of vasospasm. Cardiovascular symptoms are represented by a sudden and transient arterial hypertension which can drive to a diagnostic error and electrocardiographic abnormalities, which are directly related with the degree of vasospasm; their evolution is completely regressive. Main intracranial consequences are early hydrocephalus, worsening of consciousness and progressive ventricular distension on CT scan and vasospasm, which occurs between the 4th and the 12th day, may be asymptomatic or symptomatic, responsive for delayed ischemia, followed by deterioration of consciousness and focal neurological signs. The main factors responsible for the vasospasm are a high amount of blood in basal cisterns on CT scan; an increase of substances released by the lysis of hemoglobin in CSF; hyponatremia, hypovolemia, and decrease in cerebral blood flow. Consequences of these disorders have to be well known in the medical treatment before and after operation.
 ...
PMID:[Consequences of meningeal hemorrhage during the first days after its onset]. 228 34

Computed tomography (CT) findings in eleven patients with symptomatic cerebrospinal fluid (CSF) dissemination from cerebral glioblastoma were analyzed and, in seven cases subsequently autopsied, they were compared with histological observations. Each patient had multiple CT abnormalities including periventricular enhancement (5/11), subarachnoid enhancement (10/11) and progressive hydrocephalus (7/9) by cranial CT, and small filling defects with or without block (5/5) by CT myelography. The areas that showed periventricular or subarachnoid enhancement on CT were confirmed to have macroscopically detectable seeding at autopsy. On the other hand, microscopic deposits were more widely distributed than the enhancement suggested, and were hardly visualized on CT. In association with subarachnoid seeding, we found low-density lesions on CT which had resulted from ischemia or reinvasion of adjacent structures by disseminated glioblastoma and resulting parenchymal edema. By cranial CT, subarachnoid enhancement seems to be a very reliable sign of CSF seeding, whereas periventricular enhancement due to CSF metastases should be carefully distinguished from that due to periventricular tumor infiltration. CT myelography is capable of revealing minute metastatic spinal deposits and may be helpful for ruling out spinal seeding as well as its precise evaluation.
 ...
PMID:Symptomatic cerebrospinal fluid dissemination of cerebral glioblastoma. Computed tomographic findings in 11 cases. 239 40

Computerized tomography in 134 patients with traumatic epilepsy allowed to reveal different changes in the brain tissue, meninges and CSF spaces. Early stages were characterized by signs of meningeal adhesions. With increased duration of the disease these changes were supplemented by signs brain atrophy in the form of dilatation of the subarachnoidal spaces, internal hydrocephalus. CSF cysts were diagnosed in 5 patients, porencephaly in 2, ischemia foci in the brain in 9 patients.
 ...
PMID:[The results of computed tomography in patients with traumatic epilepsy]. 251 89


1 2 3 4 5 6 7 8 9 10 Next >>