Phaco-trab vs SICS-trab

Phaco-trab beats MSICS in terms of both safety and IOP control

Roibeard O’hEineachain

Posted: Thursday, March 1, 2018

Ganesh Venkataraman MD

Phacotrabeculectomy (phaco-trab) appears to offer better intraocular pressure control and visual rehabilitation with fewer complications, but with a slightly higher loss of endothelial cells, than small-incision cataract surgery combined with trabeculectomy (SICS-trab), according to a study by Ganesh Venkataraman MD, presented at the XXXV Congress of the ESCRS in Lisbon, Portugal.

The non-randomised comparative study included 60 eyes of 60 glaucoma patients who underwent either phaco-trab or SICS-trab, said Dr Venkataraman, Aravind Eye Hospital, Coimbatore, Tamilnadu, India.

The patients had a mean age of 66.4 years and both treatment groups included 18 eyes with primary open-angle glaucoma and 12 eyes with primary angle-closure glaucoma that had undergone peripheral iridotomy. All eyes had coexistent cataracts. The mean preoperative IOP was of 17.53mmHg in the phaco-trab group and 17.0mmHg in the SICS-trab group.

Patients were excluded from the study if they had pseudoexfoliative glaucoma, small pupils and endothelial cell counts below 2,500/mm2. Also excluded were those with retinal disease or diseases of the optic nerve other than glaucoma, or who had undergone previous ocular surgery and those aged younger than 35 years.

Dr Venkataraman noted that at six months’ follow-up, IOP was significantly better controlled in the phacotrabeculectomy group, which had a mean IOP of 13.68mmHg compared to 16.0mmHg in the SICS-trab group.

In addition, the proportion maintaining their target IOP without medication was 89.3% in the phaco-trab group, compared to only 73.1% in the SICS-trab group. Furthermore, there was only one treatment failure in the phaco-trab group compared to six in the SICS-trab group.

Twenty-three patients in both groups achieved logMAR visual acuity from 0 to 0.2 at six months postoperatively. However, more patients in the phaco-trab group achieved a visual acuity of 6/6, Dr Venkataraman noted.

The mean endothelial cell loss was significantly lower in the SICS-trab group, with cell counts falling by only 10.56%, compared to in the 13.97% in the phaco-trab group (p=0.05). Dr Venkataraman noted that the rate of intraoperative complications was only 5.7% in the phaco-trab group compared to 26.7% in the SICS-trab group.

The two complications that occurred in the phaco-trab group were choroidal detachment in one eye and a posterior capsular rent in one eye. By comparison, complications in the SICS-trab group included one case of choroidal detachment, one case of fibrinous membrane, two of posterior rent, one of vitreous in the ostium, one vitreous haemorrhage, one case of corneal filaments and one case of punctate keratitis.

This study highlights the relevance of manual small-incision cataract surgery combined with trabeculectomy in poor socioeconomic regions of the world where national health services are limited or non-existent and medical insurance is beyond the reach of many.

Ganesh Venkataraman: