Clinical profile of ultrasonographic features and visual evoked potential changes in patients of ocular trauma with opaque media – A prospective study

Abstract

To study the ultrasonographic features and VEP changes in eyes with ocular trauma having opaque media and the effect of such changes on the visual prognosis of these patients. A prospective study of total 80 patients with ocular trauma attending the eye outpatient department in a tertiary care hospital was conducted. Their USG B scan and VEP examination was done in the Radiology department and Neuromedicine department respectively.Blunt trauma was the cause of ocular injury in 60% of the patients, penetrating trauma in 25% and rest 15% had non-mechanical injury caused by acid burns, firecrackers.Complications of ocular trauma e.g. cataract, vitreous haemorrhage and retinal detachment etc. could be detected to the extent of 93.12% accuracy by ultrasonography alone as compared to only 70.22% by clinical examination when both clinical examination and ultrasonography were combined together, 100% accuracy in diagnosis was reached. 96.25% of control eyes had a visual evoked potential latency, ranging between 81-110 msec and 88.75% had a VEP amplitude ranging from 6-15 µv. 66.25% of injured eyes had delayed visual evoked potential latency with the mean latency at 123 msec and about 41.25% had reduced VEP amplitude with the mean amplitude at 6.125 µv. Thus both the latency and amplitude were decreased significantly in injured eyes as compared to control eyes. Good post-treatment visual acuity was achieved in only 27.5% of patients. : UBM is a very useful primary investigation to detect the posterior segment pathology in case of opaque media in traumatic eye. The VEP is affected in case of sight threatening findings. Thus VEP studies were more accurate than USG in predicting vision threatening ocular damage and the final visual outcome in this study.