A review of the efficacy of first generation iStent in patients with glaucoma at Auckland City Hospital

Simone Freundlich1, Kaliopy Matheos1, Shenton Chew1

Meeting:  2019 RANZCO


Date:      -

Session Title: Glaucoma

Session Time:      -

Purpose: To review the efficacy of minimally invasive glaucoma surgery (MIGS) involving the placement of first generation iStents combined with phacoemulsification in the Ophthalmology department at Auckland City Hospital.

Method: A retrospective audit of intraocular pressure in patients with a diagnosis of Glaucoma, who underwent iStent implantation combined with phacoemulsification between 2016 and 2018 at Auckland City Hospital in Auckland, New Zealand.

Results: A retrospective audit of 51 patient charts who underwent MIGS, with the placement of first generation iStents combined with phacoemulsification at Auckland City Hospital between 2016 to 2018 was completed. The average patient age was 75 years. Primary open angle glaucoma was the most common indication for MIGS (n = 30), followed by normal tension glaucoma (n = 7), pseudoexfoliation glaucoma (n = 6) and primary angle closure glaucoma (n = 5). At presentation the average IOP was 19.84 mmHg (range = 9‐32 mmHg). At listing, the average IOP was 18.62 mmHg (n = 51) with patients on 1‐2 pressure lowering drops (average = 1.6, n = 51). One‐month post‐surgery IOP decreased by 3.81 mmHg, with an average IOP of 15.3 mmHg (n = 49). At the 3‐ and 12‐month follow‐up, IOP remained lower than IOP at listing with an average of 14.96 mmHg (n = 33) and 15.58 mmHg respectively (n = 31). A slight reduction in the average number of pressure lowering drops was also noted with an average of 1.4 drops post surgery (n = 49, range 0‐3).

Conclusion: This audit found that IOP after 12‐months following surgery using first generation iStents and phacoemulsification, was lower than both the presenting and listing IOP with an average reduction of 3.68 mmHg at 12 months.