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Trabecular microbypass stents as minimally invasive approach after conventional glaucoma filtration surgery
Thomas Macher1, Heike Häberle1, Juliane Wächter1
1From the Vivantes Klinikum Neukölln (Macher, Häberle, Thannhäuser, Aurich, Pham), Department of Ophthalmology and Augenklinik Berlin-Marzahn (Wächter), Department of Ophthalmology, Berlin, Germany.
Purpose:
To evaluate long-term efficacy and safety of 2 trabecular microbypass stents in patients with advanced primary open-angle glaucoma (POAG) and insufficient intraocular pressure (IOP) after previous filtration surgery.
Setting:
Vivantes Klinikum Neukölln, Augenklinik, Berlin, Germany.
Design:
Retrospective case series.
Methods:
Eyes with uncontrolled and advanced POAG since 2014 were assessed. All eyes previously had at least 1 filtration surgery procedure. The anatomical landmarks and configuration of the anterior chamber angle had to be identified easily. Two iStents were placed nasally into Schlemm canal.
Results:
The study comprised 42 patients (42 eyes); 18 eyes had 1 previous glaucoma filtration surgery. During the follow-up of 12 months, the mean IOP in cases of primary failure of filtration surgery decreased from preoperative 23.8 mm Hg ± 3.9 (SD) to 15.2 ± 2.7 mm Hg. For cases with more than 1 previous filtration surgery, the mean IOP decreased from preoperative 26.1 ± 5.7 mm Hg to 16.3 ± 3.3 mm Hg. Medications were reduced from 2.7 ± 0.9 to 2.0 ± 1.1. No intraoperative or perioperative complications occurred.
Conclusions:
For eyes with previous filtration surgery and medically uncontrolled IOP, the implantation of 2 stents provided a minimally invasive and safe reduction of mean IOP to less than 18 mm Hg at 12 months. The number of medications was also reduced.
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