Risk of sudden visual loss following filtration surgery in end-stage glaucoma

To evaluate the effect of filtration surgery on visual acuity and visual fields in patients with end-stage glaucoma during the immediate postoperative period and to assess the risk of sudden visual loss.

Prospective interventional, consecutive case-series.

The study prospectively included consecutive patients with end-stage glaucoma who underwent trabeculectomy with mitomycin-C. The inclusion criterion was a preoperative visual field with Advanced Glaucoma Intervention Study score over 16. Main outcome measures included change in best corrected logMAR visual acuity, in mean deviation (MD) of visual field test, in number of points among the four central visual field points with a sensitivity less than 5 dB and in mean sensitivity of the four central visual field points after surgery. The incidence of intraoperative and postoperative complications was also recorded.

Twenty-one patients (21 eyes) were enrolled. Mean age was 64 years (range 31 to 78). Surgery resulted in a reduction of preoperative intraocular pressure (IOP) by 14.1 +/- 9.2 mm Hg (P < .001) and a decrease in postoperative antiglaucoma medication use (P < .001). Preoperatively the mean visual acuity was 0.77 +/- 0.78, and the mean value of the mean deviation at the visual field test was -27.94 +/- 2.7 dB. Three months after surgery, there was no significant difference in visual acuity (0.74 +/- 0.79, P = .73) and mean deviation (-27.50 +/- 2.6 dB, P = .1). Similarly there was no significant change in the visual field parameters tested to assess central visual field sensitivity. There were no intraoperative complications. Transient hypotony occurred in three eyes while one eye presented more extended hypotony. Three of these eyes experienced bleb leak (seidel).

In our case-series of consecutive patients with end-stage glaucoma, followed for 3 months after filtration surgery IOP was reduced effectively and vision was preserved with no occurrences of "wipe-out" phenomenon.