Cataract Surgery combined with excimer laser trabeculotomy to lower intraocular pressure: effectiveness dependent on preoperative IOP

Background: Cataract surgery combined with excimer laser trabeculotomy (phaco-ELT) can reduce intraocular pressure (IOP). The aim of this study was to evaluate the effect of phaco-ELT on IOP in patients as a function of preoperative IOP. Methods: Patients with open-angle glacuoma or ocular hypertension who received phaco-ELT between 01/2008 and 10/2009 were included. Patients were assigned based on preoperative IOP either to the study group (<= 21 mmHg) or control group (>21 mmHg) in this IRB-approved, prospective, consecutive case series. Visual Acuity, IOP, and number of anti-glaucoma drugs (AGD) were recorded at baseline and 12 months after phaco-ELT. Any postoperative complications were also recorded. Results: 64 eyes of 64 patients (76.5 +/- 9.4 years) were included. Baseline IOP was 19.8 +/- 5.3 mmHg (AGD 2.4 +/- 1.1) for all eyes, 16.5 +/- 2.9 mmHg (AGD 2.5 +/- 1.0) for the study group, and 25.8 +/- 2.9 mmHg (AGD 2.2 +/- 1.4) for the control group. Across the two groups, IOP was reduced by 4.5 +/- 5.9 mmHg (-23.0%, p < 0.001) and AGD by 0.9 +/- 1.5 (-38.9%, p < 0.001). For the study group IOP was reduced by 1.9 +/- 4.4 mmHg (-11. 5 %, p = 0.012) and AGD by 1.1 +/- 1.4 (-42.9%, p < 0.001), and for the control group by 9.5 +/- 5.4 mmHg (-36.6%, p < 0.001) and AGD by 0.7 +/- 1.6 (-29.5%, p = 0.085). There were no serious postoperative complications such as endophthalmitis, significant hyphema, or a severe fibrinous reaction of the anterior chamber. Conclusions: IOP remained significantly reduced from baseline 12 months after phaco-ELT regardless of preoperative IOP levels, with no major complications. The IOP reduction remained constant over the entire follow-up. Hence, phaco-ELT can be considered in glaucoma and ocular hypertensive patients whenever cataract surgery is performed, in order to further reduce IOP or to reduce the requirement for IOP-reducing medications.