The soft-shell technique in eyes with a shallow anterior chamber - a randomized trial on the influence of the ophthalmic viscosurgical device.

PURPOSE: Randomized, prospective single-blinded study to examine the properties of different ophthalmic viscosurgical devices (OVDs) regarding their ability to establish and maintain stable intraocular pressure (IOP) while performing continuous curvilinear capsulorhexis (CCC). As smaller anterior chambers (AC) pose a greater challenge in aspects of endothelial protection as well as space maintenance, this study related the results to AC dimensions as anterior chamber volume (ACV) and anterior chamber depth (ACD). MATERIALS AND

METHODS

IOP was measured using rebound tonometry with sterilized probes immediately before and after initiating CCC during cataract surgery. A total of 142 eyes scheduled for routine cataract surgery were included in this randomized trial and divided into three groups receiving hydroxypropylmethylcellulose 2.0%, (HPMC) hyaluronic acid 1.4% (HA) or a combination of HPMC with HA following the soft-shell technique (SST) during the procedure. AC dimensions were measured using Scheimpflug imaging, ACV and ACD were recorded.

RESULTS

The reduction in IOP during capsulorhexis was 58.0 ± 13.7 mmHg (N = 38) for eyes undergoing surgery with HA, 61.3 ± 10.4 mmHg for those treated with HPMC (N = 32) and 64.7 ± 13.8 mmHg using the SST (N = 72). The difference in IOP reduction between OVDs did not reach statistical significance (p = 0.066) The influence of ACV (p = 0.141) and ACD (p = 0.163) on IOP drop was not statistically significant.

CONCLUSION

The SST has shown equal abilities in stabilizing the AC during CCC even in eyes with a small or flat AC. Given the protective properties of the SST, it should be used more often even in these demanding circumstances.