Phaco + iStent implant learning curve in a teaching hospital

PurposeiStent inject^® W is a minimally invasive surgical device aimed at creating an alternative trabecular drainage of aqueous humour, reducing intraocular pressure (IOP). International reports already support efficacy and safety, but evidence is lacking about the early-stage learning curve for this device.SettingThis research was conducted in a teaching tertiary hospital in Lisbon, Portugal.DesignRetrospective study on the first 6 iStent inject^® W implants performed by 6 certified ophthalmic surgeons.MethodsAll procedures were combined with cataract surgery (phaco + iStent inject^® W). Primary outcome was total surgical time. Secondary outcomes were complications and postoperative IOP. Outcome data were collected preoperatively and at postoperative days 1, 7, 30, and 90.ResultsThirty-six patients were included (58% female). Mean age was 73.28 ± 9.65 years. Mean surgical time of first surgery was 35.16 min (range 20 to 55), with surgical time decreasing by 8.5 min throughout the learning curve. Mean preoperative IOP was 21.81 ± 4.74 mmHg with a mean need of 2 medications. At 1-month, mean IOP was 16.00 ± 3.12 mmHg (-26.64% than baseline) while resorting to less medication (2.00 ± 0.94 to 0.66 ± 0.95; p < 0.01). Trabecular meshwork haemorrhage was the most common intra-operative complication reported, and no surgical complications requiring secondary intervention were recorded.ConclusionsiStent inject^® W was perceived as a fast-learning procedure, with a significant safety profile in the first cases. The magnitude of IOP reduction of this combined procedure makes it an interesting approach to the glaucoma patient requiring cataract surgery, performed either by a resident under supervision or a glaucoma consultant.