Prone position ultrasonography in silicone filled eyes.

PURPOSE

To evaluate the efficacy of a new technique of prone position ultrasonography in cases with silicone filled eyes.

METHODS

Forty patients with prior pars plana vitrectomy and silicone oil instillation referred to a tertiary eye care centre were the subjects of this study. A prospective clinical trial was undertaken to evaluate the efficacy of prone position ultrasonography in addition to routinely performed supine position ultrasonography in these patients. The technique was undertaken by 2 independent observers and compared with the findings by indirect ophthalmoscopy or surgical results. Interobserver variability was also calculated.

RESULTS

Two spikes were observed in supine position corresponding to the intravitreal silicone oil surface and the sclera, whereas a single spike corresponding to the sclera was observed in prone position. Supine position ultrasonography yielded a diagnostic accuracy of 61.8%, which increased to 96.7% when the procedure was supplemented with prone position ultrasonography. Specificity increased from 75 to 100% by the addition of this adjuvant procedure, however, with no significant difference in the interobserver variability ('K'=0.67 Vs 'K'= 0.62).

CONCLUSION

Prone position ultrasonography is a useful adjunct to the routinely performed supine position ultrasonography in silicone filled eyes and increases the diagnostic yield.