Comparison of Short-term Postoperative Hypotony Rates of 23-gauge vs 25-gauge Needles in Formation of the Scleral Tract for Baerveldt Tube Insertion into the Anterior Chamber

Efficacy and safety of combined 27-G vitrectomy and Ahmed valve using same sclerotomy site for the tube placement: A case series

We report a retrospective case series describing the feasibility and outcomes of combined 27-G minimally invasive vitrectomy surgery (MIVS) and Ahmed® Glaucoma Valve (AGV) placement. Four eyes of four patients underwent a combined MIVS using 27-G technology and AGV implantation with the tube placement in the vitreous cavity. Preoperative and postoperative data up to 12 months were collected including the type of glaucoma, intraocular pressure (IOP), glaucoma medications, and complications. All AGVs tubes were placed in the vitreous cavity using the same sclerotomy, although a slight wound enlargement was required. After one year, IOP and glaucoma medications were reduced (41.5 ± 19.1-14.5 ± 3.1 mmHg and from 3(3-3) to 1.5 (1.5-3.5). Three patients developed cystoid macular edema. The first-reported cases of combined MIVS-27-G and AGV showed a reduction of IOP and antiglaucoma medication. Placing the tube using the same sclerotomy location is feasible but a slight enlargement may be required.

Vitrectomy and ILM peeling in rhesus macaque: pitfalls and tips for success

BACKGROUND

The non-human primate (NHP) model is ideal for pre-clinical testing of novel therapies for human retinal diseases due to its similarity to the human visual system. However, intra-ocular delivery of gene therapy or cell transplantation to the retina gets hampered by the sticky vitreous body and poorly permeable inner limiting membrane (ILM) in primates. Although vitrectomy and ILM peeling are commonly performed in patients, many pitfalls exist in carrying out these procedures in the rhesus macaque, which have not been reported previously.

METHODS

We summarised common surgical pitfalls after performing vitrectomy and ILM peeling in four eyes of two rhesus macaques (one male and one female). We provided corresponding hands-on technical tips based on our surgical experience and literature search. Orbital CT scans were compared between adult rhesus macaques and humans. High-resolution surgical videos were recorded to demonstrate each critical surgical step.

RESULTS

Due to size difference, poor post-operative compliance, and high-standard requirements of a controlled experiment, there were eleven common surgical pitfalls during vitrectomy and ILM peeling in rhesus macaque. Falling into these pitfalls may produce discomfort, add fatigue, cause surgical complications, or even lead to the exclusion of the NHP from an experimental group.

CONCLUSION

Recognition and circumvention of these pitfalls during vitrectomy and ILM peeling in NHP are essential. By focusing on these surgical pitfalls, we can better carry out preclinical tests of novel therapies for retinal diseases in the NHP model.

A Novel Tube Insertion Technique for Glaucoma Drainage Device Implantation

PURPOSE

Early hypotony after non-valved glaucoma drainage device (GDD) implantation for complex glaucomatous eyes with labile aqueous production can lead to significant visual morbidity. We therefore sought to report the early postoperative outcomes of a novel surgical technique that allows atraumatic insertion of non-valved GDDs through a much smaller 25-gauge scleral track, to minimize entry site leakage and improve safety.

METHODS

Retrospective case series of 15 consecutive cases undergoing non-valved GDD insertion into the anterior chamber using a previously unreported technique.

RESULTS

All eyes underwent successful GDD insertion using our novel technique, with no intraoperative complications. The mean preoperative intraocular pressures (IOP), at day 1, week 1 and week 3 were 31.4, 22.4, 23.7, and 25.6 mm Hg, respectively. A statistically significant IOP reduction was achieved at day 1, week 1 and week 3 postoperatively ( P <0.05) without any observed leakage at the scleral entry site. One eye (6.7%) with complex panuveitic glaucoma developed early hypotony (5 mm Hg) with shallow choroidal detachments on day 1. This was successfully managed with 1 intracameral ophthalmic viscoelastic device injection given at the slit-lamp and no further intervention.

CONCLUSIONS

This novel single needle-docking intraocular insertion manoeuvre is an easily adoptable technique to make GDD insertion through a smaller 25-gauge water-tight scleral track more efficient and less traumatic. The technique reduces scleral distortion and therefore improves surgical safety particularly in eyes with complex secondary glaucoma.

Clinical Outcomes After Ahmed Glaucoma Valve Implantation for Pediatric Glaucoma After Congenital Cataract Surgery

PRCIS

Ahmed valve success for glaucoma following congenital cataract surgery lasts at least 5 years in most eyes, and >10 years in some cases. The procedure is a valuable option for these patients.

PURPOSE

The aim of the study was to report on the results of Ahmed valve implantation in children with glaucoma following congenital cataract surgery.

PATIENTS AND METHODS

Medical records were reviewed for 41 pediatric eyes (27 patients) with glaucoma after congenital cataract surgery with Ahmed glaucoma valve (AGV) implantation between 2007 and 2018. The primary outcome measure was surgical success, defined as intraocular pressure (IOP) ≤22 mm Hg (with or without glaucoma medications) on 2 consecutive follow-up visits, without glaucoma reoperation, and without significant visual complications during the follow-up period.

RESULTS

Median age at the time of AGV implantation was 80 months (range: 14 to 146 mo) and the mean follow-up period was 61.1±46.5 months. The cumulative probability of surgical success was 95.1%, 89.8%, 83.1%, and 72.6% at 12, 24, 60, and 84 months, respectively. IOP significantly decreased from 35.8±7.4 mm Hg before valve implantation to 18.7±6.5 mm Hg at the last recorded visit (51.4% decrease; P<0.0001). Most eyes (79%) required medications for pressure control. Complications occurred in 14 eyes (34%), with 12 of these remaining successful. Early hypotony was the most common complication (19.5%). Retinal detachment occurred in 1 eye.

CONCLUSIONS

Despite a decrease in surgical success over time, AGV implantation was successfully used for IOP control in the majority of our pediatric eyes with glaucoma after congenital cataract surgery. Most complications were managed effectively and surgical success was maintained.