Four-Year Follow-Up Of Retinal Nerve Fiber Layer Thickness Changes After Combined Phaco-Elios

To describe the changes in peripapillary nerve fiber layer thickness (RNFL) in patients with glaucoma who have undergone a combined phacoemulsification-ELIOS procedure at 48 months.

Glaucomatous structural damage can be assessed by optical coherence tomography (OCT) for objective and quantitative assessment of optic nerve head and retina. In glaucoma, retinal nerve fibers are lost as the disease progresses at a faster rate than normal subjects, causing thinning of this layer (RNFL) that can be measured by OCT. Estimated average thinning of the peripapillary RNFL in healthy adults is approximately -0.52 mm/year, but it can be highly variable in glaucomatous eyes.

Retrospective, single-center chart review of adult patients diagnosed with ocular hypertension or glaucoma who underwent combined phacoemulsification with ELIOS, a 308 nm XeCl  Excimer laser delivered through an intraocular fiberoptic probe to create 10 microchannels through the trabecular meshwork. Preoperative and postoperative clinical data was collected and analyzed, and the global thickness of the peripapillary nerve fiber layer thickness using the SD-OCT (Heidelberg) was captured once a year for 48 months. The main outcome measure was the mean change in RNFL thickness from year to year as compared to normal age loss. Postoperative management and follow-up were comparable to routine standalone phacoemulsification.

57 eyes of 47 patients were included. 28(59.5%) were female and 19(40.5%) male, mean age 72.85 years. This sample included patients with open-angle glaucoma (70.1%), OHT (10.5%), chronic angle closure glaucoma (10.5%) and other types of glaucoma (8.7%). Mean intraocular pressure (IOP) at baseline (BL) and 4 years was 20.6 and 17.8 mmHg, with a mean number of medications of 1.78 and 0.35, respectively. Mean peripapillary RNFL at BL, 12, 24, 36 at 48 months was 82.63, 82.95, 82.90, 80.63 and 80.95 mm, respectively. Normalization of the data indicated a mean loss of -0.47 mm/year and a cumulative loss of 1.88 mm at 4 years for this cohort. ANCOVA analysis demonstrated the differences in thickness to be significant only between BL and year one.

Combining ELIOS at the time of cataract surgery showed to be effective for decreasing IOP and number of medications up to 4 years. Most importantly, when analyzing the RNFL thickness for a follow up period of 4 years it was showed that the decrease of thickness did not exceed the age-related loss published for non-glaucomatous eyes (0.5-0.3 mm/year), addressing the main objective of glaucoma treatment of halting or slowing down disease progression.