Needle goniotomy decreases early intraocular pressure spike compared with phacoemulsification alone

Purpose

To evaluate the effect of needle goniotomy during phacoemulsification cataract surgery on early IOP spikes in patients with glaucoma compared with phacoemulsification alone.

Design

Retrospective case control series

Methods

Cataract surgeries with concurrent goniotomy for glaucoma (n = 46) were compared with controls (n = 115) with and without glaucoma. IOP was measured prior to surgery and monitored through six months postoperatively. Between-group differences in IOP and postoperative IOP reduction were tested with ANOVA and Welch's 2-sided t-tests. Demographic, clinical, and intraoperative variables were also analyzed for significant association with postoperative IOP using univariate analysis. The incidence of IOP spike was evaluated according to two criteria: IOP > 30 mmHg or IOP > 10 mmHg above baseline.

Results

Phaco-goniotomy significantly lowered IOP at postoperative day one and month six. Following goniotomy, IOP was reduced on average 28 % (95 % CI [21, 36]) at month six compared with baseline, a mean reduction of -6.3 mmHg (95 % CI [-8.6, -4.0]), and a significantly greater reduction than in glaucoma controls (1 %, 95 % CI [-9, 7] and -0.3 mmHg, 95 % CI [-1.7, 1.1], p < 0.05). The average month six IOP following phaco-goniotomy was 12.9 mmHg (95 % CI [11.6, 14.1]), significantly lower than for glaucoma controls (15.6 mmHg, 95 % CI [14.0, 17.3], p < 0.05). The incidence of early IOP spike was significantly higher in glaucoma controls (23.1 %) than in the phaco-goniotomy cohort (6.0 %) (OR = 4.5, p < 0.05). There were no associations between CDE, ultrasound and aspiration time, or irrigation volumes on postoperative IOP. We showed that preoperative IOP was the only significant contributor to postoperative IOP reduction after phaco-goniotomy.

Conclusion

Incidence of early postoperative IOP elevation after phacoemulsification alone was 4.5 times higher than after phaco-goniotomy. Needle goniotomy may be a consideration for IOP lowering in glaucomatous eyes having cataract surgery.