Outcomes of ab interno trabeculectomy with the trabectome by degree of angle opening

Abstract

Aim: To analyse ab interno trabeculectomy (AIT) with the trabectome and combined phacoemulsification with AIT (phaco-AIT) by Shaffer angle grade (SG).

Methods: Prospective study of AIT and phaco-AIT with narrow angles of SG≤2 versus open angles ≥3. Outcomes included intraocular pressure (IOP), medications, complications, secondary surgery and success (IOP <21 mm Hg and >20% reduction without further surgery). Exclusion criteria were missing preoperative data and <1 year follow-up.

Results: Of 671 included cases, at 1 year AIT SG≤2 (n=43) had an IOP reduction of 42% from 27.3±7.4 to 15.7±3.0 mm Hg (p<0.01) versus AIT SG≥3 (n=271) with an IOP reduction of 37% from 26.1±7.8 to 16.4±3.9 mm Hg (p<0.01). In phaco-AIT with SG≤2 (n=48), IOP was reduced 24% from 20.7±7.0 to 15.7±3.6 mm Hg (p<0.01) versus phaco-AIT with SG≥3 (n=309) with an IOP reduction of 25% from 22.6±6.4 to 17.0±3.4 mm Hg (p<0.01). There was no difference between SG≤2 and SG≥3 in reduction of IOP or medications, complications, secondary surgery and success rates (p>0.05).

Conclusions: SG≤2 is not associated with worse outcomes in AIT or phaco-AIT.

Keywords: Angle; Anterior chamber; Glaucoma; Treatment Surgery.

Figure 1

Trabectome Study Group Database. Cases analysed after accounting for exclusion criteria. AIT, ab interno trabeculectomy; phaco-AIT, phacoemulsification cataract surgery combined with ab interno trabeculectomy; SG, Shaffer grade.

Figure 2

In AIT, no significant differences were found in IOP and glaucoma medications use between in patients with a narrow (SG≤2, n=43) and a deep anterior chamber angle (SG≥3, n=271) over a 1 year period. AIT, ab interno trabeculectomy; IOP, intraocular pressure; SG, Shaffer grade.

Figure 3

In phaco-AIT, no significant differences were found in IOP and glaucoma medications use between in patients with a narrow (SG≤2, n=48) and a deep anterior chamber angle (SG≥3, n=309) over a 1 year period. AIT, ab interno trabeculectomy; IOP, intraocular pressure; SG, Shaffer grade.

Figure 4

Scattergrams for AIT (top) and phaco-AIT (bottom) demonstrating IOP change from preoperative baseline to final measurement at 1 month (left) and at 12 months (right). There were no significant differences between single groups or between all AIT compared with all phaco-AIT (p>0.05). AIT, ab interno trabeculectomy; IOP, intraocular pressure.

Figure 5

Kaplan–Meier survival plots for AIT (left) and phaco-AIT (right) with success defined as a final IOP of <21 mm Hg and a >20% reduction from baseline without further surgery. No statistically significant difference between SG groups in AIT (p=0.70) and phaco-AIT (p=0.56). AIT, ab interno trabeculectomy; IOP, intraocular pressure; SG, Shaffer grade.