Role of B-scan ultrasonography in pre-operative cataract patients.

OBJECTIVE To visualize the posterior portion of eye globe in dense cataract patients with B scan ultrasound, and to find out any posterior segment lesion in such pre-operative cases. METHODS We performed diagnostic B-scan ultrasound on 750 cataract patients before surgery. This was a prospective diagnostic study which was conducted in the Department of Opthalmology, Liaquat University Eye Hospital, Hyderabad Sind, Pakistan from January 2007 to July 2007. Detailed history and some basic eye examination techniques, like slit lamp and tonometry were done in two groups of patients, traumatic (71) and non traumatic(679). Patients in the age range of 1 to 79 years of both sexes were included. Patients having already posterior segment lesions and those who had previous history of ocular surgery were excluded from the study. An ultrasound machine Nidek Echo Scan Model US-3300 with a probe of direct contact was used. RESULTS Out of 750 patients, 90 patients had posterior segment lesions. Among traumatic group of 71 patients, 39 (55%) had positive posterior segment lesions, while in the non traumatic group of 679 patients, only 51 (7%) cases had positive posterior segment lesions. Out of the 90 positive cases, 25 (3%) had retinal detachment, 14 (2%) had posterior vitreous detachment, 24 (3%) had vitreous hemorrhage, 12 (2%) were asteroid hyolosis, while posterior staphyloma and intra-ocular foreign body were found with the frequency of 9 (1.2%) and 6 (1%), respectively. CONCLUSION We concluded that two dimensional B-scan ultrasound can be one of the diagnostic tool for the detection of hidden posterior segment lesions and can be performed routinely in pre-operative cataract patients, as this would help in surgical planning. In cases, where a two dimensional B-scan is not sufficient or helpful. a three dimensional ultrasound would be justified.