Clinical outcomes of Ahmed glaucoma valve in anterior chamber versus ciliary sulcus

Abstract

PurposeTo evaluate the outcomes of Ahmed glaucoma valve (AGV) tube insertion through the anterior chamber angle (ACA) or through the ciliary sulcus (CS).Patients and methodsIn this case-control study, we retrospectively reviewed the charts of consecutive glaucoma patients who had undergone AGV implantation either through the ACA or the CS between March 2009 and December 2014. The main outcome measures were intraocular pressure (IOP), number of glaucoma medications prescribed, best corrected visual acuity (BCVA), glaucoma type, success rate, complications, and survival ratios. Statistical analysis was carried out using SPSS.ResultsThere were 68 eyes in the ACA group and 35 eyes in the CS group. There were no significant differences between the groups for age, sex, laterality, IOP, preoperative glaucoma medication number, BCVA or glaucoma type (P>0.05). The postoperative follow-up period was 27.2±16.5 months and 30.2±17.7 months for the ACA and the CS groups (P=0.28); IOP values were significantly reduced at the last visit to 16.4±7.2 mm Hg and 14.4±6.8 mm Hg. The difference in the last-visit IOP between the groups was not significant (P=0.06), but the IOP reduction ratio was higher in the CS group (P=0.03). There was no significant difference in the number of postoperative medications (P=0.18). Postoperative complications were similar, but the incidence of flat anterior chamber was higher in the ACA group (P=0.05).ConclusionsThe use of an AGV can control IOP in the majority of cases whether placed in the ACA or the CS. The IOP reduction ratio seemed to be higher in the CS group.

Figure 1

Preoperative and postoperative intraocular pressure (IOP) comparison between anterior chamber angle and the ciliary sulcus groups.

Figure 2

Kaplan–Meier survival curves after Ahmed glaucoma valve implantation in the anterior chamber angle and ciliary sulcus. The success rates were 98.3 and 97.1% at 6 months, 94.7 and 93.8% at 12 months, and 81.3 and 89.6% at 24 months, 76.3 and 82.7% at 36 months, 53.1 and 62% at 48 months, and 53.1 and 62% at 60 months in the anterior chamber angle and ciliary sulcus groups, respectively. The difference between the survival curves was not statistically significant (P=0.77).