Faculty Bibliography

PRCIS:A literature review of selective laser trabeculoplasty (SLT) energy dose-response found no definitive relationship between intraocular pressure (IOP) reduction with respect to total or pulse energy, race, pigmentation, or application pattern. PURPOSE:SLT is a safe and effective treatment for lowering IOP. Although evidence is mounting for the advantage of its use as a first-line treatment for IOP reduction, the SLT procedures in use vary widely. The purpose of this literature review was to investigate whether there were any relationships between SLT energy and efficacy for lowering IOP in the published literature. METHODS:A literature review was undertaken that included studies in which energy levels required for successful SLT treatment were investigated: in general, with respect to angle pigmentation, race or ethnicity, and treatment arc extent. RESULTS:There was no indication that higher (or lower) energy used in the treatment leads to greater (or less) IOP reduction. Similar results were obtained regarding the level of trabecular meshwork pigmentation. Race was not found to be associated with altered dose response in SLT. There were indications that treating the full 360 degrees, as opposed to smaller arcs, could be beneficial for more IOP reduction. IOP reduction from SLT was found to be similar to that provided by topical medications. CONCLUSIONS:The optimal energy level of SLT needed for IOP reduction has not yet been definitively established, with all reported pulse energies resulting in similar IOP reduction. Furthermore, similar lack of conclusive findings exists regarding optimal SLT energy dosage for use in different races and degrees of trabecular meshwork pigmentation. This parameter and each of the abovementioned factors requires further research.

PURPOSE:To report 3-year outcomes of the HORIZON study comparing cataract surgery (CS) with Hydrus Microstent (Ivantis, Inc) implantation versus CS alone. DESIGN:Multicenter randomized clinical trial. PARTICIPANTS:Five hundred fifty-six eyes from 556 patients with cataract and primary open-angle glaucoma (POAG) treated with 1 or more glaucoma medication, washed out diurnal intraocular pressure (IOP) of 22 to 34 mmHg, and no prior incisional glaucoma surgery. METHODS:After phacoemulsification, eyes were randomized 2:1 to receive a Hydrus Microstent or no stent. Follow-up included comprehensive eye examinations through 3 years. MAIN OUTCOME MEASURES:Outcome measures included IOP, medical therapy, reoperation rates, visual acuity, adverse events, and changes in corneal endothelial cell counts. RESULTS:Three hundred sixty-nine eyes were randomized to microstent treatment and 187 to CS only. Preoperative IOP, medication use, washed-out diurnal IOP, and glaucoma severity did not differ between the two treatment groups. At 3 years, IOP was 16.7 ± 3.1 mmHg in the microstent group and 17.0 ± 3.4 mmHg in the CS group (P = 0.85). The number of glaucoma medications was 0.4 ± 0.8 in the microstent group and 0.8 ± 1.0 in the CS group (P < 0.001), and 73% of microstent group eyes were medication free compared with 48% in the CS group (P < 0.001). The microstent group included a higher proportion of eyes with IOP of 18 mmHg or less without medications compared with the CS group (56.2% vs. 34.6%; P < 0.001), as well as IOP reduction of at least 20%, 30%, or 40% compared with CS alone. The cumulative probability of incisional glaucoma surgery was lower in the microstent group (0.6% vs. 3.9%; hazard ratio, 0.156; 95% confidence interval, 0.031-0.773; P = 0.020). No difference was found in postoperative corneal endothelial cell loss between groups. No procedure- or device-related serious adverse events resulting in vision loss occurred in either group. CONCLUSIONS:Combined CS and microstent placement for mild to moderate POAG is safe, more effective in lowering IOP with fewer medications, and less likely to result in further incisional glaucoma filtration surgery than CS alone at 3 years.

A healthy corneal endothelium is required for corneal clarity. Both the glaucoma disease state and its various forms of treatment can have adverse effects on the corneal endothelium. Both the presence of glaucoma and the magnitude of intraocular pressure (IOP) elevation are related to endothelial cell loss (ECL). Topical medical therapy, laser procedures, and both traditional surgeries-trabeculectomy and tube-shunts-and newer minimally invasive glaucoma surgeries have variable effects on ECL. This review will summarize the reported effects of glaucoma and its treatment on ECL. Concerns for corneal endothelial cell health should be part of the decision-making process when planning glaucoma therapy for lowering IOP, with added caution in case of planned device implantation in eyes with pre-existing ECL and low endothelial cell density (ECD) at high risk for corneal endothelial decompensation.

PURPOSE/OBJECTIVE:To assess whether an association exists between pretreatment corneal hysteresis (CH) and the magnitude of intraocular pressure (IOP) and medication burden reduction following microinvasive glaucoma surgery (MIGS). METHODS:Retrospective chart review of 84 eyes from 57 patients with CH measurements who underwent trabecular meshwork MIGS in a glaucoma practice in New York City with follow-up visits at 3-6 and 9-12 months. MIGS included canaloplasty, goniotomy, microbypass stents, or a combination thereof. RESULTS:The lowest and middle CH tertiles experienced significantly reduced mean IOP at 3-6-month follow-ups (p = .007, < .001), whereas the highest tertile did not (p = .06). At 9-12-month follow-ups, a significant mean IOP reduction only persisted in the middle tertile (p = .001). For medication burden reduction, only the highest CH tertile experienced significant mean reductions at both 3-6- and 9-12-month follow-ups (p = .015, .028). Notably, 7 patients in the lowest CH tertile failed MIGS and required an additional surgical or laser procedure within 24 months of MIGS, whereas only 3 patients failed in the other tertiles (likelihood ratio < .05). Multivariate analysis excluding MIGS failures demonstrated an inverse association between CH and the magnitude of post-operative IOP reduction at both 3-6- and 9-12-month follow-ups when controlling for baseline IOP and medication changes (p = .002, .026). CONCLUSION/CONCLUSIONS:There was an inverse association between pretreatment CH and the magnitude of IOP reduction following surgery. There is also evidence of an increased need for repeat surgery or other intervention in patients with lower CH who undergo MIGS.

Purpose/UNASSIGNED:To compare the safety and efficacy of two different techniques for implantation of the XEN Gel Stent, a minimally invasive surgical device for the treatment of refractory glaucoma. Methods/UNASSIGNED:A retrospective chart review of eyes that received ab interno or ab externo XEN Gel Stent placement from February 2017 to October 2019 was conducted. A single surgeon (NMR) performed all operations. Eyes that received the XEN implant concomitant with a glaucoma drainage device insertion or that were lost to 6-month follow-up were excluded. Intraocular pressure (IOP) change, change in glaucoma medications, frequency of slit lamp revision procedures, and frequency of secondary glaucoma surgeries were the primary outcomes compared between groups. Results/UNASSIGNED:Fifty eyes that underwent ab interno placement and 30 eyes that underwent ab externo placement were studied. The ab interno cohort demonstrated a mean IOP reduction of 8.4 ± 1.7 mmHg (28.6% decrease) by 12 months, compared to a mean reduction of 12.8 ± 3.0 mmHg (40.1% decrease) in the ab externo group (p = 0.208). Mean reduction in medication use was 1.81 ± 0.29 medications in the ab interno group and 1.86 ± 0.37 in the ab externo group (p = 0.913). By 12 months, 58% of ab interno eyes had required 5-fluorouracil injection compared to 36.7% of ab externos (p = 0.105). Bleb needling was applied to 42% and 26.7% of the eyes, respectively (p = 0.231). A second glaucoma surgery was necessary for 20% of the ab interno cohort and 10% of the ab externo cohort (p = 0.351). Conclusion/UNASSIGNED:There were no differences in outcomes between ab interno and ab externo placement of the XEN Gel Stent. Both approaches are safe and effective for lowering IOP.

Purpose:To evaluate the intraocular pressure (IOP)-lowering effect of a multi-pressure dial (MPD) at targeted negative pressure settings. Methods:Prospective, intrasubject controlled study of 65 healthy subjects randomized to receive no negative pressure for 60 minutes or negative pressure application at designated levels of 25%, 50%, and 75% of baseline IOP for 20 minutes each. The main outcome measure was mean IOP with application of negative pressure. Results:< 0.001) in comparison with baseline. There was one minor adverse event, a corneal abrasion, that was unrelated to device wear. Conclusions:Negative pressure application to the periocular space with a multi-pressure dial can produce titratable IOP reduction while the device is worn with active negative pressure. To our knowledge, this technology represents the first nonpharmacologic, nonlaser, nonsurgical method for IOP reduction. Translational Relevance:This represents the first study demonstrating the IOP-lowering ability of the multi-pressure dial, a device that uses a novel IOP-lowering strategy by delivering negative pressure to the periocular region.

OBJECTIVE:To determine the relationship between optic disc hemorrhage (DH) and corneal hysteresis (CH). METHODS:Consecutive patients with prior or current photographic evidence of unilateral DH who had undergone CH measurement with the Ocular Response Analyzer (ORA; Reichert, Buffalo, NY) were enrolled. Eyes with a history of corneal disease, refractive surgery, or bilateral DH were excluded. Central corneal thickness (CCT), visual field data, 5 consecutive previous intraocular pressures (IOPs), and maximum documented peak IOP were obtained by chart review. Vertical cup-to-disc ratio (VCDR), the presence of neuroretinal rim notching, number of clock hours of beta zone parapapillary atrophy (ßPPA), and eye with greater ßPPA width were determined from photographs by 2 masked expert examiners. RESULTS:We identified and analyzed 49 patients with photographically documented unilateral DH. Compared to fellow non-DH eyes, eyes with DH had lower CH (8.7 ± 1.9 vs 9.2 ± 1.7; p = 0.002), higher IOP (15.6 ± 3.6 vs 14.3 ± 4.1; p = 0.017), and greater VCDR (0.79 ± 0.13 vs 0.68 ± 0.23; p < 0.001), but were similar with respect to CCT, ßPPA extent, rim notching, peak IOP, and visual field damage (all p > 0.05). Using multivariate conditional logistic regression analysis, only CH (p = 0.012) and VCDR (p = 0.004) predicted the laterality of the DH. CONCLUSIONS:Lower CH and greater VCDR are independently associated with DH. This suggests that CH may be a structural biomarker for an abnormality of the optic nerve complex that may be associated with progressive glaucoma. Eyes in which DH were detected had lower CH.

Purpose/UNASSIGNED:To evaluate reduction in intraocular pressure (IOP) and medications for open-angle glaucoma (OAG) patients 12 months post-ab-interno circumferential viscodilation (VISCO360, Sight Sciences, Menlo Park, CA) in conjunction with cataract surgery. Setting/UNASSIGNED:Surgical center (New York, United States). Design/UNASSIGNED:Retrospective study of all OAG patients treated with 360-degree ab-interno viscodilation with cataract surgery by a single surgeon (NR) having 12 months of follow-up. Eyes were stratified by baseline IOP. Group 1: ≥18 mmHg (n=111). Group 2: <18 mmHg (n=69). Methods/UNASSIGNED:IOP was measured using Goldmann applanation tonometry. Medications, the number of medication-free eyes in each group at 12 months, and adverse events (AE) are reported. Analysis includes descriptive statistics and t-tests evaluating change from baseline. Results/UNASSIGNED:Groups 1 and 2 had mean baseline IOP of 22 and 14.3 mmHg. Medication use was 0.9 and 1.1 for Groups 1 and 2. At 12 months IOP for Group 1 was reduced 22% to 17.2 mmHg (p<0.0001) on 1.0 medications (p=0.7). IOP for Group 2 was similar to baseline (15.4 mmHg) but with a reduction in medications to 0.6 (p<0.05). The proportion medication free at 12 months was 32% and 47% for Groups 1 and 2 versus 34% and 26% at baseline, respectively. There were few AE (hyphema 1.7%, IOP elevation >10 mmHg >30 days post-op 1.1%, mild inflammation <1%) and no secondary surgical interventions excepting a single paracentesis, one-day postoperative. Discussion/UNASSIGNED:Treatment goals for the two groups differed. Pressure reduction (Group 1) or medication reduction (Group 2). Viscodilation achieved significant IOP reduction in Group 1 and medication reduction in Group 2 with many patients (both groups) medication free at 12 months. AE were infrequent and transient. Conclusion/UNASSIGNED:Circumferential ab-interno viscodilation can be combined with cataract surgery and provide an IOP lowering and medication reduction benefit sustained for at least 12 months, for many patients with OAG.

PURPOSE/OBJECTIVE:To investigate the long-term effectiveness of intraocular pressure (IOP) and medication reduction in patients who have undergone micropulse transscleral cyclophotocoagulation (mTS-CPC). DESIGN/METHODS:Retrospective chart review. PARTICIPANTS/METHODS:A total of 73 eyes of 62 patients treated no more than 1 time with mTS-CPC in a practice in New York City with at least 1 year of follow-up. METHODS:Treatment was 100 seconds of mTS-CPC with energy titrated on the basis of visual acuity. Paired t test and multivariable analysis were performed with SAS (SAS Institute Inc, Cary, NC). MAIN OUTCOME MEASURES/METHODS:Visual acuity, IOP, medication burden, phthisis, and development of macular edema were followed. RESULTS:Average initial IOP was 25.5±9.4, and average number of initial medications was 3.1±1.1. At 1 year, average IOP was 13.8±7.0 (46% reduction) and average number of medications was 2.5±1.0 (19% reduction). A total of 11 of 15 patients (73.3%) initially taking an oral carbonic anhydrase inhibitor before CPC did not require the oral carbonic anhydrase inhibitor 1 year after treatment. Seventy-six percent of patients obtained at least 20% IOP reduction. Multivariate analysis found IOP reduction was associated with power used and preoperative IOP, whereas medication reduction was associated with initial medication burden. Notably, there was a 57% reduction in IOP at 2500 mW power and a 30% reduction at 2000 mW power. No patients developed macular edema or phthisis from the procedure. Some 18.8% of patients with 20/400 vision or better experienced persistent vision loss of ≥2 lines after the procedure, and 10% of patients with light perception to count finger vision progressed to no light perception (NLP) after the procedure. Of patients with 20/400 vision or better, 12.5% gained ≥2 lines of visual acuity on the Snellen chart at the postoperative year 1 visit. In addition, 15.4% of patients with count fingers to NLP vision improved at the postoperative year 1 visit after treatment. One of 6 patients (16.7%) with NLP gained vision at the postoperative year 1 visit. CONCLUSIONS:This study provides evidence that mTS-CPC is a clinically useful procedure associated with good long-term medication burden reduction and IOP reduction that follows a dose-response pattern related to power used.

Cataract and glaucoma are the leading causes of blindness worldwide and commonly coexist in elderly patients. Endocyclophotocoagulation (ECP) is a minimally invasive approach for glaucoma management that is amenable to combination with cataract surgery. We review the literature on ECP and evaluate intraocular pressure reduction efficacy when combined with phacoemulsification. Several studies demonstrate that phacoemulsification and ECP (PECP) successfully reduces intraocular pressure (IOP) and decreases medication burden. PECP has a minimal side effect profile, and risks are limited to those usual post-phacoemulsification. Most importantly, PECP allows for all future procedures including trabeculectomy or tube implantation if necessary.