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V Nangia

Publications and source records attributed to V Nangia.

7 recordsLinked to original sources
PubMed1998

Emotional arousal and activation of the visual cortex: an fMRI analysis.

Functional activity in the visual cortex was assessed using functional magnetic resonance imaging technology while participants viewed a series of pleasant, neutral, or unpleasant pictures. Coronal images at four different locations in the occipital cortex were acquired during each of eight 12-s picture presentation periods (on) and 12-s interpicture interval (off). The extent of functional activation was larger in the right than the left hemisphere and larger in the occipital than in the occipitoparietal regions during processing of all picture contents compared with the interpicture intervals. More importantly, functional activity was significantly greater in all sampled brain regions when processing emotional (pleasant or unpleasant) pictures than when processing neutral stimuli. In Experiment 2, a hypothesis that these differences were an artifact of differential eye movements was ruled out. Whereas both emotional and neutral pictures produced activity centered on the calcarine fissure (Area 17), only emotional pictures also produced sizable clusters bilaterally in the occipital gyrus, in the right fusiform gyrus, and in the right inferior and superior parietal lobules.

Adult↗
PubMed1995

Optic nerve head circulation in untreated ocular hypertension.

AIMS: The laser Doppler technique was used to compare the capillary blood speed measured at localised sites of the optic nerve head in stable, untreated ocular hypertensive patients with that measured in healthy normal subjects. The stereophotogrammetric technique was also used to measure the retinal nerve fibre layer thickness at the disc margin in the eyes of the patients. METHODS: Doppler broadening measurements were made at superior and inferior temporal disc sites in 18 eyes of 10 ocular hypertensive patients and in 12 eyes of seven age and sex-matched normal subjects. RESULTS: On average, Doppler broadening and, hence, capillary blood speed were significantly higher (p = 0.018) in the patients than in the normal subjects. The largest values of Doppler broadening in the patients were measured at sites adjacent to the thinnest retinal nerve fibre layer. Linear regression analysis showed a significant inverse relation (p = 0.0004) between Doppler broadening and nerve fibre layer thickness in left eyes, and a nearly significant relation (p = 0.06) in right eyes. At temporal sites of the optic nerve head there is a compensatory relation between a thinning nerve fibre layer and a locally increasing blood supply to the optic nerve head. CONCLUSION: Together with previous observations of fluorescein filling defects in similar patients, these results indicate that there is spatial heterogeneity of blood flow in the optic nerve head in stable, untreated ocular hypertensive patients.

Adult↗
PubMed1992

Standardised echography in the differential diagnosis of extraocular muscle enlargement.

Standardised echography is well documented for its use in the evaluation of enlarged extraocular muscles in orbital disease, but is still a largely underdeveloped imaging method in Britain. This paper demonstrates the technique of muscle ultrasound scanning and the characteristic echographic findings in a variety of extraocular muscle diseases, as illustrated by five case reports. The role of echography in the management of such cases is discussed.

Aged↗
PubMed1992

Metastatic endophthalmitis caused by Clostridium perfringens.

A case of metastatic endophthalmitis due to Clostridium perfringens originating from the biliary tract is reported. The grave visual prognosis and the importance of early detection and treatment of the primary source of infection are emphasised.

Aged↗
PubMedDate not supplied

Changes in respiratory function tests during pregnancy.

Anatomical, physiological and biochemical adaptations that occur during pregnancy are profound. Changes in respiratory physiology are a part of the same process. In the present study of 70 selected women, 50 pregnant and nonpregnant control, it was found that out of seven parameters studied five showed changes. There were changes in respiratory frequency, tidal volume, vital capacity, inspiratory capacity and expiratory reserve volume. Maximum voluntary ventilation and timed vital capacity did not change. RF, VT, VC and IC rose significantly while ERV had a significant fall. These changes may be affecting ante-intranatal behaviour of pregnant women and their pregnancy outcome.

Adult↗