Comparison of Silicone- and Porous-Plate Ahmed Glaucoma Valves

Figures & data

Table 1 Demographic and Preoperative Data for Patients Treated with the Porous Plate (Model M4) and Silicone Plate (Model FP7) Ahmed Glaucoma Valves

	Porous Plate (Model M4) n=26	Silicone Plate (Model FP7) n=26	P value
Eyes, right/left [n]	17/9	10/16	0.052
Age, years [mean ± SD]	67.0 ± 10.1	67.7 ± 11.2	0.700
Gender [n (%)]			0.158
Female	8 (30.8%)	13 (50.0%)
Male	18 (69.2%)	13 (50.0%)
Ethnicity [n (%)]			0.469
African	9 (34.6%)	8 (30.8%)
Asian	0	2 (7.7%)
Caucasian	14 (53.8%)	14 (53.8%)
Hispanic	3 (11.5%)	1 (3.8%)
Mixed race	0	1 (3.8%)
Lens Status [n (%)]			0.441
Phakic	9 (34.6%)	7 (26.9%)
Pseudophakic	17 (65.4%)	17 (65.4%)
Aphakic	0	2 (7.7%)
Glaucoma diagnosis [n (%)]			0.384
Primary open-angle glaucoma	14 (53.8%)	15 (57.7%)
Neovascular glaucoma	6 (23.1%)	5 (19.2%)
Inflammatory (uveitic) glaucoma	5 (19.2%)	2 (7.7%)
Combined mechanism glaucoma	0	2 (7.7%)
Congenital glaucoma	0	1 (3.8%)
Aphakic glaucoma	0	1 (3.8%)
Pseudoexfoliation glaucoma	1 (3.8%)	0
Previous Glaucoma Surgery [n (%)]			0.938
None	17 (65.4%)	15 (57.7%)
Trabeculectomy (± EX-PRESS)	8 (30.8%)	8 (30.8%)
Phaco-PCIOL and trabeculectomy	1 (3.8%)	1 (3.8%)
EX-PRESS with iStent	0	1 (3.8%)
Triple procedure	0	1 (3.8%)

Abbreviations: Phaco-PCIOL, phacoemulsification and posterior chamber intraocular lens implantation; Triple procedure, phacoemulsification and posterior chamber intraocular lens implantation, trabeculectomy, and penetrating keratoplasty.

Table 2 Comparison of Efficacy and Complications in Patients Treated with the Porous Plate (Model M4) and Silicone Plate (Model FP7) Ahmed Glaucoma Valves

	Porous Plate (Model M4) n = 26	Silicone Plate (Model FP7) N = 26	P value
Intraocular pressure [mmHg; mean ± SD]
Preoperative	33.79 ± 10.54	29.91 ± 6.55	0.118
Postoperative month 12	17.94 ± 10.95	13.60 ± 4.69	0.141
Glaucoma medications [mean ± SD]
Preoperative	3.31 ± 1.29	3.12 ± 1.34	0.600
Postoperative month 12	1.89 ± 1.54	1.64 ± 1.40	0.605
Hypertensive phase [n (%)]	15 (57.7%)	13 (50.0%)	0.578
Surgical success at 12 months [n (%)]	14 (53.8%)	23 (88.5%)	0.005
Complications [n (%)]
Flat anterior chamber	2 (7.7%)	2 (7.7%)	1.000
Hypotony	3 (11.5%)	3 (11.5%)	1.000
Corneal edema	1 (3.8%)	1 (3.8%)	1.000
Tube occlusion	1 (3.8%)	2 (7.7%)	1.000
Tube repositioning	0	1 (3.8%)	1.000
Wound leak	1 (3.8%)	0	1.000
Choroidal effusion	1 (3.8%)	4 (15.4%)	0.350
Exposed plate/tube	1 (3.8%)	3 (11.5%)	0.610
Diplopia	1 (3.8%)	2 (7.7%)	1.000
Hemorrhagic choroidal detachment	1 (3.8%)	0	1.000
Loss of vision >than 2 Snellen lines	3 (11.5%)	4 (15.4%)	1.000

Figure 1 Mean intraocular pressure after M4 and FP7 Ahmed Glaucoma Valve implantation. The intraocular pressure was significantly reduced in both groups compared with baseline (P < 0.05 at all time points). Comparisons of the individual time points showed no significant differences.

Abbreviations: Pre, before surgery; D, day(s); M, month(s).

Figure 2 Number of glaucoma medications at baseline and postoperatively after M4 and FP7 Ahmed Glaucoma Valve implantation. The number of medications was significantly reduced in both groups compared with baseline (P < 0.05 at all time points). There were no significant differences at any time point in comparisons between the two groups.

Abbreviations: Pre, before surgery; D, day(s); M, month(s).

Figure 3 Kaplan–Meier curve cumulative probability of success in patients treated with model M4 and model FP7 Ahmed Glaucoma Valve implantation. Success was defined as 5 mmHg ≤intraocular pressure ≤21 mmHg (with or without medications), without loss of light perception and without additional glaucoma procedures. The success of eyes after model FP7 was significantly higher compared with model M4 implantation (P = 0.005).

Figure 4 Kaplan–Meier curve cumulative probability of success in patients treated with model M4 and model FP7 Ahmed Glaucoma Valve implantation. In this analysis, success was defined as 30% lowering of intraocular pressure from baseline (with or without medications), without loss of light perception and without additional glaucoma procedures. The success of eyes after model FP7 was significantly higher compared with model M4 implantation (P = 0.014).