Purpose
To evaluate long-term intra-ocular pressure (IOP) lowering efficacy of ELT based on patient observations made over a period of five years. ELT (fiberoptic, ab interno delivery, 308 nm) creates five to ten channels through the trabecular meshwork and inner wall of Schlemm’s canal to lower outflow resistance and thereby lower IOP.
Methods
46 eyes of 46 patients aged 64 ± 18 years (mean ± SD) (M/F: 9/37) participated in this prospective, single site, single surgeon (UG) study. Diagnosis: Primary open-angle glaucoma: 35 eyes; Ocular hypertension: 7; Secondary glaucoma: 2; PEX glaucoma: 2. The IOP was measured by applanation, without wash out, pre-op, 1day, 1 month (M), 3, 6, 12 M, 2 years (Y), 3 ,4, 5 Y post op. Surgical procedure: Following paracentesis, the ELT probe (diameter 0.5 mm) traverses the anterior chamber to contact the trabecular meshwork and excise ten, 200 µ channels into Schlemm’s canal in the lower nasal quadrant. Number of eyes observed at: 1 day post-op: 46; 1 M: 46; 3 M 46; 6 M: 46; 1Y: 45; 2Y: 44; 3Y: 41; 4Y: 32; 5Y: 28.
Results
IOP (mm Hg): pre-op: 25.5±- 6.3; post-op 1 day: 13.3 ± 4.5; 1M: 16.3 ± 4.3; 3M: 16.0 ± 2.8; 6M: 16.22 ± 5.5; 12M: 16.0 ± 3.8; 2Y: 15.6 ± 3.0; 3Y: 15.2 ± 3.7; 4Y: 15.2 ± 3.4; 5Y: 15.9 ± 3.0 Statistical tests: ANOVA with repeated measurements and t-tests. SPSS 17.0 (Bonferroni correction). At all times, the IOP values were highly significantly lower than the pre-op values (alpha: p <0.001). The number of IOP lowering medications also decreased from 1.9 ± 0.9 pre-op to 0.9 ± 1.1 at 5 years. There were no intraoperative or postoperative complications.
Conclusions
Significant IOP reduction following ELT, over 35% at all times, has been documented to remain stable in these patients for at least 5 years post op. Additionally, following ELT, the number of IOP lowering medications was significantly reduced.
Keywords: 578 laser •
568 intraocular pressure •
466 clinical (human) or epidemiologic studies: treatment/prevention assessment/controlled clinical trials