Four articles. Four minutes. | Issue #22
Laser: Conventional SLT showed greater 6-month effectiveness than direct SLT in a real-world matched cohort
Diagnostics: Less complex retinal vessel networks on fundus photos linked to faster visual field loss
Epidemiology: Unspecified glaucoma in inpatient records resembled primary angle-closure glaucoma in China, with more mixed patterns in the UK
Surgery: Triamcinolone plus early aqueous suppression was associated with fewer Ahmed hypertensive phases, but their effects cannot be separated
Early Outcomes of Direct versus Conventional Selective Laser Trabeculoplasty in a Propensity-Matched Cohort
Methods
This single-center retrospective study compared conventional 360° selective laser trabeculoplasty (SLT) with automated direct SLT (dSLT) in 247 propensity-matched eyes from 147 patients who completed treatment, including eyes with prior glaucoma procedures. Complete success through six months required no further IOP-lowering intervention and either at least 20% IOP reduction without more medication or IOP at or below baseline with at least one fewer topical medication.
Results
Estimated six-month complete success was higher with conventional SLT than dSLT (30.5% vs 16.2%; adjusted HR for failure with dSLT, 1.66; P=0.020). Partial success, which allowed medication increases, did not differ significantly after adjustment. In 84 eyes, adjusted IOP reduction favored conventional SLT by 2.98 mmHg (P=0.010); medication burden was similar at six months. Adverse events were uncommon, but pain prevented completion of 7 of 152 dSLT attempts (4.6%) versus 0 of 102 conventional SLT attempts. Counting incomplete attempts as failures preserved the direction of the efficacy findings.
Conclusion
In this retrospective cohort that included treatment-experienced eyes, conventional SLT was associated with better six-month IOP lowering and complete success.
Our Angle
In clinic, the patients we laser rarely look like a pivotal-trial population. Many already have low or near-target IOP, use multiple medications, or have undergone prior SLT, MIGS, or incisional surgery. That all-comer population is the main strength of this study because it reflects the patients we actually treat. It also makes interpretation more difficult. Nearly half of eyes had prior SLT; matching accounted for whether prior SLT had occurred, but not the number of prior treatments, their timing, or the prior response. Treatment was nonrandomized and changed over calendar time, and after dSLT adoption some eyes received conventional SLT because dSLT could not be performed. Six-month follow-up and incomplete month-6 IOP data further limit conclusions about durability.
Our early dSLT experience also included a practical learning curve. Pain control, positioning, and the limbal-detection workflow evolved as we gained experience. Those implementation factors were not captured well enough to adjust for and may have influenced early real-world performance. For now, conventional SLT remains my benchmark when pressure-lowering effectiveness is the priority. The potential advantage of dSLT is different: a rapid, automated, noncontact treatment could reduce procedural friction and potentially expand access to laser. This study did not measure access, throughput, cost, or patient preference, so that benefit remains plausible rather than demonstrated. A modest difference in per-treatment effectiveness could still matter differently at a population level if substantially more patients can receive laser, but that tradeoff needs to be measured rather than assumed. A prospective randomized trial comparing dSLT with conventional SLT is now underway at MUSC with standardized protocols and a 12-month IOP endpoint.
DISCLOSURE: Drs. Jella An and Jason Dossantos coauthored the featured study, which received no financial support. Dr. An reports consulting and speaker relationships with Alcon, manufacturer of the dSLT platform, and is a principal investigator for the ongoing randomized dSLT-versus-SLT trial at MUSC.
Diagnostics
Photography-based Retinal Vasculometry and Visual Field Progression in Primary Open Angle Glaucoma.
Design: Retrospective cohort study
Journal: American Journal of Ophthalmology, September 2026
Authors: Nishida et al.
Less complex retinal vessel networks and straighter arteries on baseline disc photographs were associated with faster visual field loss in a retrospective cohort of 1,595 eyes from 929 glaucoma suspects and patients with POAG. Over a mean 10.3 years, lower venous and arterial fractal dimension, a measure of branching complexity, and lower arterial tortuosity tracked with faster mean deviation decline. Adding these measurements to clinical variables improved model fit only slightly within the same cohort, and the venous association was less certain in bootstrap analyses. Treatment changes were not modeled, and external validation is needed to establish how well these measurements predict progression in a new patient.
Epidemiology
Incidence patterns and genetic validation of primary glaucoma subtypes among 1 million adults in China and the UK.
Design: Prospective two-biobank cohort study
Journal: British Journal of Ophthalmology, September 2026
Authors: Li et al.
Unspecified glaucoma in hospital records showed different subtype patterns in China and the UK, based on epidemiologic and genetic analyses of two prospective biobanks totaling 1,004,833 adults. Over about 12 years, 9,301 incident primary glaucoma cases were identified, most without a specified subtype. Polygenic-risk and demographic patterns suggested that unspecified cases more closely resembled primary angle-closure glaucoma (PACG) in China, with a more mixed pattern in the UK. Incidence rose with age; PACG incidence was about twice as high in women as in men in both cohorts, and UK POAG incidence was about 4.5 times as high in Black as in White participants. These findings help interpret coded research datasets, but inpatient records miss many outpatient cases, especially POAG, and the volunteer cohorts do not provide representative population incidence estimates.
Surgery
Intraoperative Triamcinolone Acetonide Injection During Ahmed Glaucoma Valve Surgery Suppresses the Occurrence of the Postoperative Hypertensive Phase.
Design: Retrospective multicenter cohort study
Journal: Journal of Glaucoma, August 2026
Authors: Hirota et al.
Sub-plate triamcinolone was associated with fewer hypertensive phases after Ahmed valve implantation in this five-center retrospective cohort of 182 eyes (7.8% vs 35.4% within 3 months). However, the groups differed in a second intervention that directly affects the same outcome: all triamcinolone-treated eyes started aqueous suppressants once IOP exceeded 10 mmHg, whereas the comparison group generally resumed glaucoma medications only after IOP rose above 21 mmHg. Prior randomized studies have shown that early aqueous suppression itself can reduce the Ahmed hypertensive phase, and the authors acknowledge that the combination may have acted synergistically. Therefore, the large difference in hypertensive-phase rates cannot be attributed to triamcinolone alone, and adjustment for baseline covariates does not remove this protocol-level confounding. A randomized study using identical postoperative medication thresholds is needed to isolate the effect of sub-plate triamcinolone.
AAO and NANOS advise shared decision-making regarding NAION during semaglutide therapy, citing mixed evidence and low absolute risk.
A pivotal phase 2/3 subretinal gene therapy trial met its 12-month endpoint in X-linked retinitis pigmentosa, showing significant low-luminance acuity responder rates.
A slit-lamp ab externo bleb procedure entered first-in-human use in 11 glaucoma eyes, with formal studies now underway in Canada.
FDA issues a Class II recall covering over 3,000 Pearle Vision 1 day contact lenses distributed in Minnesota, Ohio, and Wisconsin after lenses were found to have incorrect power.
The first laser used in ophthalmology was not the argon laser but the:
A. Ruby laser
B. Carbon dioxide laser
C. Nd:YAG laser
D. Excimer laser
See answer at bottom of newsletter.
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The Open Angle is a weekly glaucoma research digest for busy eye care professionals.
Four articles worth knowing, in under four minutes.
Edited by Jella An, MD, MBA and Jason Dossantos, MD.
The Open Angle is an educational editorial product. It is not medical advice. Readers should review original sources before changing practice.
TRIVIA ANSWER EXPLANATION
The first laser used in ophthalmology was not the argon laser but the:
A. Ruby laser
The ruby laser entered ophthalmology almost immediately after Theodore Maiman demonstrated the first working laser in May 1960. By fall 1961, Charles J. Campbell at Columbia-Presbyterian and Charles Koester of American Optical had used a prototype ruby photocoagulator to destroy a retinal tumor in one of medicine's earliest therapeutic laser procedures.
The ruby laser's clinical use was brief. Its pulse output and spot size varied, making dose control difficult. Francis L'Esperance treated the first human eye with an argon laser in 1968. Argon's controllable blue-green beam soon displaced ruby, which is why later generations associated early retinal laser with argon rather than its short-lived predecessor.