Ultrasound Biomicroscopy of Sclerotomy Sites After Pars Plana Vitreoretinal Surgery: Our Observations and Review of Literature

Joshi D, Venkatesh P, Tewari HK
Dr Rajendra Prasad Centre for Ophthalmic Sciences, All India Institute of Medical Sciences, Ne w Delhi, India.

Background:

To study changes occurring at the sclerotomy sites in the postoperative period after pars plana vitreoretinal surgery using ultrasound biomicroscopy.

Methods:

This case series at a tertiary care hospital studied 22 eyes of 22 consecutive patients undergoing primary standard pars plana vitreous surgery. Ultrasound biomicroscopy was used for examining the sclerotomy sites at 1 month and again at 3 months. Gape and vitreous incarceration at the internal lip of the sclerotomy were graded as 0 to 3 and were compared between the early and the late images.

Result:

All (100%) sclerotomy sites showed gaping in the first evaluation, reducing to 41% at the second evaluation. Vitreous incarceration increased from 53% at one month evaluation to 80% at the third month evaluation. Mean gape at the active port, light port and infusion port was 1.87, 2.15 and 2.08 respectively (P=0.2), decreasing to 0.46, 0.54 and 0.43 respectively (P=0.37). Mean vitreous incarceration at these ports was 0.60, 0.70 and 0.85 (P=0.27) increasing to 1.03, 1.31 and 1.38 respectively at the second evaluation (P=0.10). The difference between the ports for gape or vitreous incarceration was not statistically significant. Early severe gape did not correlate with severity of later incarceration. Gape and incarceration did not show a statistically significant difference between the phakic and nonphakic eyes.

Conclusion:

Gaping of the inner lip of the sclerotomy persists even at 3 months post-operatively in a significant number of cases. There is no direct correlation between the degree of gape in the early post-operative period and severity of vitreous incarceration in the later period.