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

Ninety-six patients with transient ischemia attacks were examined by transcranial Doppler (TCD), carotid color-coded ultrasonic imagine, brain computed tomographic scan (CT), compared with digital subtract angiography (DSA), MRI and MRA were done in some cases. The abnormality of CT and MRI was 30.2% and 74.1%, respectively. The most common findings were lacunar infarction or cerebral atrophy. Sixty-two cases fulfilled the TCD criteria of definitive arterial stenosis (64.5%) and three cases of arteriovenous malformation, among whom 27 patients (43.5%) carried out the examination of DSA. There was an excellent coincidence between the DSA and TCD findings, although DSA showed more vessels involved in some patients. Of the 96 cases, the intracranial arterial stenosis or occlusion was in 48.5% and the extracranial in 17.8%. The younger patients (age < 60 years) were subject to involvement of unilateral intracranial artery, but the older had predominantly the bilateral intracranial arterial and extracranial carotid or subclavian arterial lesions.
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PMID:[Intra- and extra-cranial arterial lesions in TIA patients]. 857 51

The suture model for middle cerebral artery occlusion (MCAO) was used to induce acute ischemia in rats remotely within a magnetic resonance (MRI) scanner. Serial MR diffusion weighted imaging (DWI) was performed during remote MCAO using an echo planar imaging technique. MR perfusion imaging was performed before and after occlusion using the bolus tracking technique. Transient apparent diffusion coefficient (ADC) changes were detected in six of seven rats as early as 2.7 +/- 1.5 min post MCAO. ADC values declined transiently to 70.1 +/- 6.0% of control and recovered to 95.5 +/- 6.8% of control within 3.3 +/- 2.9 min. These ADC changes propagated bidirectionally away from the ischemic core with a speed of 3.0 +/- 1.1 mm/min. Transient ADC decreases only occurred in ischemic areas characterized by moderately decreased tissue perfusion. Propagation toward cortical regions with severe tissue perfusion deficits was not detected. DWI can detect the earliest dynamic, reversible ADC changes in the ischemic tissue. The speed of propagation of the decreasing ADC wave, the waveform characteristics, and the occurrence in moderately perturbated tissue are compatible with cortical spreading depression.
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PMID:MR detection of cortical spreading depression immediately after focal ischemia in the rat. 859 52

The utility of a noninvasive steady state susceptibility-contrast MRI technique for continuous measurement of relative cerebral blood volume (rCBV) during global transient ischemia and subsequent hyperemia in a feline ischemia model is demonstrated. The measurements were obtained during a 10-min period of occlusion and 1-h period of reperfusion. Maximal hyperemic responses in gray matter, basal ganglia, and white matter (observed at 7,7, and 5 min, respectively) were 1.9 +/- 0.5, 1.8 +/- 0.3, and 1.7 +/- 0.6 times greater than baseline CBV (mean +/- SEM). Thirty to forty minutes after onset of reperfusion, CBV returned to normal. Thereafter, it decreased below baseline, nearing the control level by 1 h after onset of reperfusion. Steady state susceptibility-contrast MRI permits continuous, in vivo mapping of alterations in CBV.
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PMID:Continuous assessment of relative cerebral blood volume in transient ischemia using steady state susceptibility-contrast MRI. 862 80

A review: The skeleton, the peripheral soft tissues, and the joints have become important indications to use MRI routinely. About 25-35% of daily examinations focus on these anatomic sites. Superior contrast resolution, the option of different imaging planes, and the unsurpassed visualization of bone marrow, fibrous and hyaline cartilage, ligaments, and tendons are the reasons for the overwhelming success of this imaging method. MRI often provides the direct way to diagnosis. More and more the so-called "step by step" approach to diagnosis by imaging methods is being abandoned in favor of the primary use of MRI. The present survey summarizes the main indications for MRI in the field of the musculoskeletal system, in adults as well as in children. Special topics like tumors, inflammation, ischemia, and trauma are discussed. Some anatomic sites like the carpal joint, the shoulder, and the knee are presented in more detail.
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PMID:[MR tomography (MRT) of the skeleton, peripheral soft tissues and joints--current overview]. 867 37

A patient with conus syndrome following arteriogenic impotence is described. A 62-year-old man became impotent. 7 months after the onset, he was admitted because of a sudden left sensorimotor disturbance (L2 to S5 segments) when he awoke. A marked bilateral reduction of cutaneous sensation in the S2 to S5 dermatome distribution persisted. An MRI of the spinal cord demonstrated no abnormal lesion on T2-weighted and Gadolinium enhanced images. Angiography of the pelvic artery showed severe arteriosclerotic findings. We diagnosed this case as a conus syndrome due to ischemia in the conus medullaris. The impotence in our case was considered to be arteriogenic because there was no detection of the bilateral deep arteries of the penis on angiography after an intracorporeal PGE1 injection. In this case, arteriogenic impotence might be a prodrome of a conus medullaris infarction.
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PMID:[A case of conus syndrome following arteriogenic impotence]. 874 51

We described a 67-year-old right handed man with a left internal carotid artery occlusion, who developed monocular photopsia that supervened neovascular glaucoma. He had an antecedent transient motor aphasia. His photopsia, exaggerated by light, persisted intermittently. Orbital bruit was obtained on the left, more clearly during the photopsia. Brain MRI, cerebral angiography, and duplex sonography of carotid and ophthalmic arteries indicated left internal carotid artery (ICA) occlusion with collateral circulation through the ophthalmic artery. Visual evoked potentials (VEPs) revealed a prechiasmal disturbance of the optic pathway of the left side. The patient had carotid endarterectomy of the left ICA, and his visual disturbance has gradually improved. Ocular symptoms due to ICA ischemia are commonly transient visual loss with dark background known as amaurosis fugax. Neovascular glaucoma is sometimes complicated with carotid artery occlusion. However, photopsia associated with carotid artery occlusion is rare. Photopsia mimics scintillating scotomata, but the latter precedes migraine and is biocular and homonymous, ascribable to spreading depression from the occipital lobe. Retinal or prechiasmal optic pathway might be influenced by poor circulation of the ophthalmic artery. In addition, disturbance of light adaptation due to retinal hypoperfusion may be possible reason. Neovascular glaucoma is intractable, once developed. Therefore, atypical scintillating visual disturbance must be recognized as a sign of carotid artery insufficiency and supervened glaucoma to prevent it.
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PMID:[Monocular photopsia preceding with neovascular glaucoma due to internal carotid artery occlusion; a case report]. 874 54

Clinical evaluation of 123I-iomazenil, a new imaging agent for central-type benzodiazepine receptors with SPECT, was performed in patients with ischemic cerebrovascular disease. We investigated 15 patients with angiographically-proven severe occlusive lesions (occlusion or > 70% stenosis) in the unilateral carotid system. 123I-iomazenil SPECT images were compared with cerebral blood flow (CBF) images and the cerebral perfusion reserve, which were measured using the "split dose 123I-IMP SPECT method" before and after the intravenous injection of 1 g of acetazolamide. For the detection of ischemic lesions, CBF images were superior to 123I-iomazenil images based on visual analysis. Regarding the count ratio of the affected MCA territory to the non-affected (L/N), 123I-IMP was lower than 123I-iomazenil in most of the cases. In five patients showing "crossed cerebellar diaschisis" by 123I-IMP, asymmetry of the cerebellar accumulation was observed in only one patient with 123I-iomazenil, which was less prominent than with 123I-IMP. There was no significant correlation between the L/N ratio with 123I-iomazenil and the cerebral perfusion reserve in the affected MCA territory. However, in some cases showing a decreased L/N ratio (< 90%) with 123I-iomazenil, a decreased CBF with normal perfusion reserve and cerebral hemi-atrophy were observed with 123I-IMP and MRI, which suggested the influence of neuronal loss due to chronic ischemia. These results indicate that 123I-iomazenil SPECT, which provides new information regarding neuronal loss due to ischemic damage to the brain, is useful for the evaluation of ischemic cerebrovascular disease.
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PMID:[Evaluation of 123I-iomazenil SPECT in patients with ischemic cerebrovascular disease: comparative study with 123I-IMP SPECT]. 874 3

White matter signal hyperintensities (WMSH) are commonly seen on MRI of elderly subjects. The purpose of this study was to characterize metabolic changes in the white matter of elderly subjects with extensive WMSH. We used water-suppressed proton (1H) magnetic resonance spectroscopic imaging (MRSI) to compare six subjects with extensive WMSH with eight age-matched elderly subjects with minimal or absent WMSH, and phosphorus (31P) MRSI to compare nine subjects with extensive WMSH and seven age-matched elderly subjects without extensive WMSH. Relative to region-matched tissue in elderly controls, extensive WMSH were associated with increased signal from choline-containing metabolites, no significant change of signal from N-acetylaspartate, and a trend to a decreased phosphomonoester (PME) resonance. These findings suggest that WMSH may be associated with an alteration of brain myclin phospholipids in the absence of axonal damage. There were no differences in energy phosphates, consistent with lack of ongoing brain ischemia. Within the group with extensive WMSH, PME resonance measures were significantly lower in WMSH than in contralateral normal-appearing white matter. These results provide information on pathophysiology of WMSH and a basis for comparison with WMSH in Alzheimer's disease, vascular dementia, multiple sclerosis, and other diseases.
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PMID:1H and 31P magnetic resonance spectroscopic imaging of white matter signal hyperintensity areas in elderly subjects. 874 91

Cortical vein thrombosis without sinus involvement is rarely diagnosed, although it may commonly be overlooked. We report four cases of cerebral venous thrombosis limited to the cortical veins. The diagnosis was made on surgical intervention in one patient and by angiography in three patients. Together with a survey of the published cases, the clinical and neuroimaging patterns of our patients allow delineation of several features suggestive of cortical venous stroke. Focal or generalized seizures followed by hemiparesis, aphasia, hemianopia, or other focal neurologic dysfunction in the absence of signs of increased intracranial pressure should suggest this possibility. Neuroimaging (CT, MRI) shows an ischemic lesion that does not follow the boundary of arterial territories and often has a hemorrhagic component, without signs of venous sinus thrombosis. Conventional angiography demonstrates no arterial occlusion but may show cortical vein thrombosis corresponding to the infarct, although these may also be nonspecific findings. The role of MR angiography, which is well-established in sinus thrombosis, remains to be assessed in patients with brain ischemia due to isolated cortical vein occlusion.
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PMID:The stroke syndrome of cortical vein thrombosis. 875 7

A partial syndrome of hemisphere disconnection was observed in a 63 year-old woman, following an anterior and middle corpus callosum infarct on MRI. Notably, we found left ideomotor apraxia, diagonistic apraxia, left-year extinction on dichotic listening, but no left-hand anomia nor left visual field anomia. A left tactile extinction in dichaptic condition is interpreted as resultant of a dysregulation of the attentional balance between the two hemispheres. This detailed neuropsychological study permits a correlation between the callosal syndrome and the lesion. We suggest that an occlusion of the anterior callosal artery could explain this limited ischemia.
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PMID:[Interhemispheric disconnection syndrome caused by partial infarction of the corpus callosum: neuropsychological study and MRI]. 876 26


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