PubMed Health⌕ Search

Biomedical subjects

K Ray-Chaudhuri

Publications and source records attributed to K Ray-Chaudhuri.

9 recordsLinked to original sources

Accuracy of the clinical diagnosis of postencephalitic parkinsonism: a clinicopathologic study.

The accuracy of the clinical diagnosis of postencephalitic parkinsonism (PEP) is unknown. We determined the validity of the clinical diagnosis of PEP by presenting 105 records with neuropathologic diagnoses of PEP (n = 7), progressive supranuclear palsy (n = 24), Parkinson's disease (n = 15), dementia with Lewy bodies (n = 14), multiple system atrophy (n = 16), corticobasal degeneration (n = 10), Creutzfeldt-Jakob disease (n = 4), and other dementia disorders (n = 15), as clinical vignettes to six neurologists unaware of the autopsy findings. The neurologists' own clinical diagnoses were compared with neuropathologic diagnoses for measures of diagnostic accuracy, including reliability (kappa statistics), sensitivity and positive predictive values for the first and last visits. The group reliability for the diagnosis of PEP was almost perfect (kappa = 0.91, 0.9). The mean sensitivity at the first visit was 86% (range, 71-100%) with minimal change at the last visit (83%; range, 71-100%). Positive predictive values remained unchanged (100%). The high reliability, sensitivity and positive predictive values of the clinical diagnosis of PEP indicate that neurologists identify this disorder even when they report that they have never evaluated a case. In our data set, the best predictors for the diagnosis of PEP included onset below middle age; symptom duration lasting more than 10 years, and the presence of oculogyric crisis. History of encephalitis lethargica, present in most PEP cases, was an important individual diagnostic predictor. Copyright 1998 Lippincott Williams & Wilkins

Journal Article↗

Accuracy of the clinical diagnosis of corticobasal degeneration: a clinicopathologic study.

The accuracy of the clinical diagnosis of corticobasal degeneration (CBD) is unknown. To determine its diagnostic accuracy, we presented 105 cases with known neuropathologic diagnoses, including CBD (n = 10), progressive supranuclear palsy (PSP, n = 24), Parkinson's disease (n = 15), diffuse Lewy body disease (n = 14), multiple system atrophy (n = 16), postencephalitic parkinsonism (n = 7), Pick's disease (n = 7), Creutzfeldt-Jakob disease (n = 4), Alzheimer's disease (n = 4), vascular parkinsonism (n = 3), and Whipple's disease (n = 1), as clinical vignettes to six neurologists unaware of the autopsy findings. Reliability was measured with the kappa statistics. The neurologists' clinical diagnoses were compared with clinicopathologic diagnoses for sensitivity, specificity, and positive predictive values at first and last clinic visits. The group reliability for the diagnosis of CBD significantly improved from moderate for the first visit (mean = 34 months after onset) to substantial for the last (68 months after onset). For the first visit, mean sensitivity for CBD was low (35%), but specificity was near-perfect (99.6%). For the last visit, mean sensitivity minimally increased (48.3%), and specificity remained stable. False-negative misdiagnoses mainly occurred with PSP. False-positive diagnoses were rare. The extremely low sensitivity of the clinical diagnosis of CBD suggests that this disorder is markedly underdiagnosed. Although the validity of the clinical diagnosis might have been improved if neurologists could have examined these patients, more important is that this disorder was misdiagnosed by the primary neurologists. In our data set, the best predictors for the diagnosis of CBD included limb dystonia, ideomotor apraxia, myoclonus, and asymmetric akinetic-rigid syndrome with late onset of gait or balance disturbances.

Basal Ganglia↗

The effect of captopril on the superior mesenteric artery and portal venous blood flow in normal man.

1. Measurements of superior mesenteric artery and portal venous blood flow were made non-invasively along with systemic and other regional (cardiac index, forearm and cutaneous blood flow) vascular responses to acute ingestion of the ACE inhibitor captopril (50 mg) or placebo (50 mg vitamin C), in 12 healthy subjects while supine and during head-up tilt. 2. After captopril, superior mesenteric artery and portal blood flow rose markedly with a reduction in superior mesenteric artery vascular resistance. Supine blood pressure was unchanged but cardiac index and forearm blood flow rose; during head-up tilt, blood pressure fell in some subjects. 3. There was a rise in levels of plasma renin activity and a fall in levels of plasma angiotensin II after captopril. After placebo, there were no significant changes in splanchnic blood flow, systemic or other regional responses and in biochemical measurements, while supine. 4. Our studies indicate that captopril is a potent dilator of the splanchnic vascular bed and suggest that this action may contribute to its therapeutic effects. The studies indicate a role for angiotensin II in the control of this large vascular bed although other agents (bradykinin, prostacyclin) may contribute.

Adult↗

The relationship between blood flow and pulsatility index in the superior mesenteric artery at rest and during constrictor stimuli in normal subjects.

The relationships between superior mesenteric artery blood flow (SMABF) and pulsatility index (PI) measurement during rest (25 subjects) and stimuli constricting the SMA (16 subjects) have been studied in normal subjects. At rest and during constrictor stimuli, SMABF and PI were highly reproducible (r = 0.89, p < 0.01 for SMABF, and r = 0.97, p < 0.001 for PI) between two observers. There was significant correlation between changes in SMABF, PI, and SMA vascular resistance during the constrictor stimuli, except during head-up tilt when PI was unchanged. Both PI and SMABF measurements are reproducible and can be used to monitor physiological changes in suitable (18 of 25) subjects. PI measurement, although semiquantitative, by itself can also be used to monitor these changes. This may be also of importance in pathological situations such as intestinal ischemia, where measurement of volume blood flow may be less accurate due to irregularities of the vessel wall. PI measurement, however, ideally should not be used in studies involving postural change.

Adult↗