Surgical safety and efficacy of a multi-stent system, the comet stent, in Baerveldt glaucoma implant surgery: a prospective pilot study

This study aimed to introduce a new technique for lowering intraocular pressure (IOP) using a multi-stent system after the implantation of a Baerveldt glaucoma implant (BGI) and evaluate its clinical effectiveness.

Prospective case series.

Six patients with uncontrolled refractory glaucoma were enrolled between December 2021 and May 2022. Six 6-0 nylon sutures were preoperatively inserted into the tube of a BGI. These sutures were named "comet stents" (CSs). BGI implantation was performed, and the CSs were removed one-by-one whenever the IOP rose during the follow-up period. IOP was measured 30-60 min after the removal of each CS, and the reduction in IOP was recorded to assess the effect of CS removal. IOP reduction and the effect of CS removal on IOP reduction were evaluated for 6 months. The cut and trimmed stented tubes were examined with scanning electron microscopy, and the ratio of the patent cross-sectional area to the total luminal area (PCSA, %) and the luminal area occupation rate per stent (%) were calculated.

The mean (±standard deviation) IOP decreased from 31.5 ± 2.8 mmHg at the baseline to 14.8 ± 8.3 mmHg at 1 month, 8.8 ± 4.7 mmHg at 3 months, and 9.2 ± 3.4 mmHg at 6 months. The IOP reduction induced by CS removal ranged from 0 to 19 mmHg. The mean PCSA was 52.7 ± 1.7%, and the mean luminal area occupation rate per stent was 7.9 ± 0.3%.

The use of CSs is an effective technique for controlling IOP in a step-by-step manner after BGI surgery.