Direct selective laser trabeculoplasty (DSLT) appears to be a safe and effective variation of selective laser trabeculoplasty (SLT) for reducing intraocular pressure (IOP) in patients with glaucoma, with higher-energy usage leading to better results, according to findings from a first-in-human nonrandomized prospective clinical trial. Results of the study, led by Mordechai Goldenfeld, MD, and colleagues, were published in Translational Vision Science & Technology.
The study’s primary endpoints were reduced IOP at one and three months, and secondary endpoints were reduced medication usage and reduced IOP at six months. The study was conducted on 15 eyes from 15 patients, 10 with open-angle glaucoma (OAG), four with ocular hypertension, and one with pseudoexfoliation glaucoma. Subjects had an IOP ≥ 22 mmHg and were treatment-naïve or waited for ocular medication washout before DSLT irradiation. Patients were administered 100 or 120 532-nm Q-switched laser shots (0.8 – 1.4 mJ) over 1.5 or 2.3 seconds on their limbus, automatically directed by image analysis and eye tracking. Treatment outcomes were assessed at one and three hours, one day, one week, and one, three, and six months after DSLT.
The baseline mean IOP in all eyes was 26.7 mmHg (standard deviation [SD] ± 2.3). This value was significantly reduced over time to 21.7 mmHg at one month (SD ± 4.2), 20.8 mmHg at three months (SD ± 2.5), and 21.5 mmHg at six months (SD ± 4.1). Percentage of IOP reduction was 18.1%, 21.4% and 18.8%, respectively.
Notably, in six patients who received the 1.4 mJ/shot treatment, mean IOP at six months was 19.3 mmHg (SD ± 2.0, p = 0.03), a decrease of 27.1% from the baseline. Additionally, there was a significant reduction in number of hypotensive medications needed after DSLT versus the number needed at time of screening, from 1.6 (SD ± 1.0) to 0.4 (SD ± 0.7, p = 0.03). No serious adverse events were recorded in the study.
According to the authors, it is possible that, with the availability of the automated DSLT variation of SLT that does not require gonioscopy, general ophthalmologists and other trained health professionals will be more inclined to use it, thus improving access to a laser surgery treatment option for patients.