Preoperative measurements for cataract surgery: a comparison of ultrasound and optical biometric devices.

PURPOSE: To evaluate differences in preoperative measurements and refractive outcomes between ultrasound and optical biometry when using the Barrett Universal II intraocular lens (IOL) power formula. METHODS: In this consecutive case series, cataract extraction and IOL implantation cases from two surgical centers in Toronto, Canada, were recruited between January 2015 and July 2017. Differences between ultrasound (applanation or immersion A-scan) and optical biometry (IOLMaster 500) were compared for axial length (AL), anterior chamber depth and refractive outcomes. The primary outcome was the percentage of cases in each cohort within ± 0.50D of refractive error. RESULTS: In total, 527 cataract cases underwent IOLMaster testing. Of these, 329 eyes (62.4%) were also measured by applanation A-scan, and the other 198 eyes (37.6%) received immersion A-scan testing. Applanation ultrasound led to 5.8%, 16.0% and 46.4% of eyes within ± 0.25D, ± 0.50D and ± 1.00D of refractive error, respectively, whereas the IOLMaster 500 led to 48.5%, 77.1% and 94.9%, respectively (n = 293, ± 0.50D: p < 0.001). Immersion ultrasound led to 31.2%, 57.6% and 91.2% of eyes within ± 0.25D, ± 0.50D and ± 1.00D of refractive error, respectively, whereas the IOLMaster 500 led to 42.4%, 72.0% and 92.0%, respectively (n = 125, ± 0.50D: p = 0.001). Applanation (n = 329, A-scan AL: 23.64 ± 1.67 mm, IOLMaster AL: 24.20 ± 1.70 mm, p < 0.001) and immersion ultrasound (n = 198, A-scan AL: 25.01 ± 2.06 mm, IOLMaster AL: 25.08 ± 2.13 mm, p = 0.002) yielded significantly lower AL values compared to optical biometry measurements. CONCLUSIONS: Optical biometry yielded a significantly larger percentage of cases within ± 0.50D of refractive error compared to ultrasound biometry when using the Barrett Universal II IOL power formula.

A comparative analysis of 12 intraocular lens power formulas.

PURPOSE: To evaluate the accuracy of 12 intraocular lens (IOL) power calculations: Barrett Universal II, EVO, Haigis, Hill-RBF version 2.0, Hoffer Q, Holladay 1, Holladay 2, Kane, Olsen, SRK/T, Super Formula and T2. METHODS: In this retrospective consecutive case series, cataract extraction and IOL implantation cases in Toronto, Canada, were recruited between 2017 and 2019. Refractive predictions were compared to the observed 1-month postoperative spherical equivalent to determine the refractive error for each formula cohort. Subgroup analysis stratified eyes into short (≤ 22.5 mm)-, intermediate (22.5 mm-25.5 mm)- and long (≥ 25.5 mm)-axial length (AL) cohorts. The primary outcome was the percentage of cases within ± 0.50D of refractive error. RESULTS: Overall, 764 cataract cases were analyzed. Formulas with the highest percentage of eyes within ± 0.50D of refractive error, in decreasing order, were: Kane (77.7%), Barrett Universal II (77.4%), EVO (76.6%), T2 (76.4%), Super (75.9%), Holladay 1 (75.4%), Hill-RBF 2.0 (74.7%), SRK/T (72.6%), Hoffer Q (72.5%), Haigis (71.7%), Olsen (67.4%) and Holladay 2 (67.3%). For short-AL eyes, the Holladay 1 formula was most accurate (n = 69, 78.3% within ± 0.50D), and for long-AL eyes, the Barrett Universal II formula was most accurate (n = 116, 76.7% within ± 0.50D). Kane, Barrett, EVO, T2 and Super formulas led to a significantly lower mean absolute error compared to the open-source calculations with optimized lens constants (p-value: < 0.001-0.042). CONCLUSIONS: The Kane formula was the most accurate formula for the overall analysis. The Holladay 1 calculation was most accurate for short-AL cases, whereas the Barrett Universal II was superior for long-AL eyes.

Cyclodialysis cleft repair: A multi-centred, retrospective case series.

IMPORTANCE: There is a paucity of evidence analysing the treatment of cyclodialysis clefts. BACKGROUND: We describe outcomes following the treatment of this rare condition at six centres internationally. DESIGN: Retrospective case series. PARTICIPANTS: Thirty-six patients with a cyclodialysis cleft from 2003 to 2017 were recruited. METHODS: Clefts were treated with cycloplegic agents, laser therapy and/or surgery. MAIN OUTCOME MEASURES: Postoperative best recorded visual acuity (BRVA), intraocular pressure (IOP) and the rate of cleft closure. RESULTS: The mean age was 45 ± 17 years and 29 (80.6%) patients were male. One eye (2.8%) received only medical therapy, 5 (13.9%) received laser, 14 (38.9%) underwent surgery after laser failure and 16 (44.4%) eyes received exclusively surgery. Over 80% of eyes had a BRVA improvement of more than two lines. Closure was attained in 30 eyes (93.8%; n = 32), with postoperative stabilized IOP ≥ 12 mmHg in 29 eyes (80.6%; n = 36) and postoperative BRVA ≤20/50 in 20 eyes (58.8%; n = 34). Improved postoperative BRVA was related to better preoperative BRVA (P = 0.006) and preoperative IOP ≥ 4 mmHg (P = 0.03). There was no significant difference between treatment approach for IOP ≥ 12 mmHg (P = 0.85) or postoperative BRVA ≤20/50 (P = 0.80). Only two eyes at last follow-up required IOP lowering medication. CONCLUSIONS AND RELEVANCE: There was a high closure rate with most eyes eventually requiring surgery. Clinically significant improvements in BRVA were found in most eyes. Improved postoperative BRVA was significantly related to better preoperative BRVA and IOP.

Interocular Axial Length and Corneal Power Differences as Predictors of Postoperative Refractive Outcomes after Cataract Surgery.

PURPOSE: To determine whether differences between eyes in axial length (AL) and corneal power (K) on optical biometry are predictive of refractive outcomes. DESIGN: Retrospective cohort study. PARTICIPANTS: A total of 729 patients (1458 eyes) who underwent bilateral phacoemulsification at TLC (Mississauga, Ontario, Canada) from September 2013 to August 2015. METHODS: We compared the proportion of patients having >0.5 diopters (D) of refractive error from target stratified by interocular axial length differences (IALDs) and interocular K differences (IKDs) between eyes as measured by optical biometry (IOL-Master, Carl Zeiss Meditec, Oberkochen, Germany). Analysis was repeated for 0.25 D or 1.0 D targets and for patients with uncorrected visual acuity (UCVA) >0.3 logarithm of the minimum angle of resolution (logMAR) postoperatively. MAIN OUTCOME MEASURES: Proportions, odds ratios (ORs), and corresponding 95% confidence intervals (CIs) were computed using generalized estimating equations to account for within-patient correlation. RESULTS: Some 79.1% of eyes were ≤0.5 D of refractive target, 47.0% were ≤0.25 D, and 97.2% were ≤1.0 D. The OR of having a refractive outcome >0.5 D from target for IALD cutoff of 0.2 mm was 1.4 (1.1-1.8), of 0.3 mm was 1.6 (1.2-2.1), and of 0.4 mm was 1.8 (1.3-2.5). This translates to 70.0% (63.5-75.7) within target for IALD of ≥0.4 mm versus 80.7% (78.4-82.9) for <0.4 mm. For a given patient with IALD, the chance of being off target was similar for the shorter and longer eye. Eyes outside of target were twice as likely to be <-0.5 D than >0.5 D. Interocular K difference was largely not associated with prediction error, yet larger IKD-flat, steep, and average were associated with increased odds of UCVA >0.3 logMAR postoperatively. CONCLUSIONS: Interocular axial length difference of as little as ≥0.2 mm is associated with a higher chance of >0.5 D of refractive error from target and worse UCVA. Interocular K difference was not associated with worse refractive error from target, although a difference of ≥0.4 D was associated with worse UCVA. These cutoffs should be considered in preoperative planning and discussion with patients. Future study is required to assess whether repeating measurements, using adjunctive measurement devices, or attempting to separate true differences from artifact based on preoperative refractive characteristics reduces residual refractive error.

Visual and Refractive Outcomes in Manual versus Femtosecond Laser-Assisted Cataract Surgery: A Single-Center Retrospective Cohort Analysis of 1838 Eyes.

PURPOSE: Femtosecond laser-assisted cataract surgery (FLACS) has emerged as an alternative to manual cataract surgery (MCS) for corneal incision and capsulorhexis creation, as well as nuclear fragmentation. This study compares postoperative refractive and visual outcomes in eyes receiving MCS or FLACS. DESIGN: Single-center, comparative, retrospective cohort analysis. PARTICIPANTS: Consecutive eyes receiving FLACS and MCS from July 1, 2012, to July 31, 2015, at a single tertiary care center. METHODS: Demographic data, ocular history, preoperative measurements and biometry, and postoperative surgical results were retrospectively obtained and statistically analyzed using a generalized linear mixed model adjusting for differences in baseline characteristics and within-patient correlation. A 2-tailed P value <0.05 was considered statistically significant throughout the study. MAIN OUTCOME MEASURES: Percentage of eyes achieving absolute error (AE) ≤0.5 diopters (D). Secondary outcomes included percentage of eyes with AE ≤0.25 D and ≤1.0 D, and percentage of distance-targeted eyes achieving uncorrected distance visual acuity (UDVA) of 20/20 or better, 20/25 or better, and 20/30 or better. RESULTS: A total of 883 eyes received MCS and 955 received FLACS among 1089 patients. Some 82.6% of FLACS eyes and 78.8% of MCS eyes had ≤0.5 D of AE at 3 weeks, representing an adjusted odds ratio (OR) of 1.28 (95% confidence interval [CI], 0.98-1.66) of FLACS relative to MCS being within target. Some 97.1% of FLACS and 97.2% of MCS eyes had ≤1.0 D of AE (OR, 0.96; 95% CI, 0.57-1.60) and 49.3% of FLACS and 46.3% of MCS eyes, ≤0.25 D of AE (OR, 1.13; 95% CI, 0.91-1.39). Factors predictive of a favorable refractive outcome included axial length between 22 and 24.8 mm, receiving a toric intraocular lens, less preoperative cylinder, and greater preoperative average keratometry. There was no significant difference in the percentage of patients targeted for distance who achieved UDVA of 20/20 or better (P = 0.30), 20/25 or better (P = 0.06), or 20/30 or better (P = 0.66) vision. CONCLUSIONS: Postoperatively, there was no statistically significant difference found between eyes undergoing FLACS and eyes undergoing MCS with respect to refractive and visual outcomes.

Efficacy, Safety, and Risk Factors for Failure of Standalone Ab Interno Gelatin Microstent Implantation versus Standalone Trabeculectomy.

PURPOSE: To compare the efficacy, safety, and risk factors for failure of standalone ab interno gelatin microstent implantation with mitomycin C (MMC) versus trabeculectomy with MMC. DESIGN: International, multicenter, retrospective interventional cohort study. PARTICIPANTS: Three hundred fifty-four eyes of 293 patients (185 microstent and 169 trabeculectomy) with no prior incisional surgery. METHODS: Consecutive eyes with uncontrolled glaucoma underwent microstent or trabeculectomy surgery from January 1, 2011 through July 31, 2015 at 4 academic ophthalmology centers: Toronto, Canada; Frankfurt, Germany; Salzburg, Austria; and Leuven, Belgium. MAIN OUTCOME MEASURES: Primary outcome measure was hazard ratio (HR) of failure, with failure defined as 2 consecutive intraocular pressure (IOP) readings of <6 mmHg with vision loss or >17 mmHg without glaucoma medications (complete success) at least 1 month after surgery despite in-clinic interventions (including needling). Secondary outcome measures included IOP thresholds of 6 to 14 mmHg and 6 to 21 mmHg and same thresholds allowing for medications (qualified success), interventions, complications, and reoperations. RESULTS: Baseline characteristics were similar, except more men (56% vs. 43%), younger patients (average, by 3 years), better preoperative visual acuity (22% vs. 32% with 0.4 logarithm of the minimum angle of resolution vision or worse), and more trabeculoplasty (52% vs. 30%) among microstent eyes. The adjusted HR of failure of the microstent relative to trabeculectomy was 1.2 (95% confidence interval [CI], 0.7-2.0) for complete success and 1.3 (95% CI, 0.6-2.8) for qualified success, and similar for other outcomes. Time to 25% failure was 11.2 months (95% CI, 6.9-16.1 months) and 10.6 months (95% CI, 6.8-16.2 months) for complete success and 30.3 months (95% CI, 19.0-∞ months) and 33.3 months (95% CI, 25.7-46.2 months) for qualified success. Overall, white ethnicity was associated with decreased risk of failure (adjusted HR, 0.49; 95% CI, 0.25-0.96), and diabetes was associated with increased risk of failure (adjusted HR, 4.21; 95% CI, 2.10-8.45). There were 117 and 165 distinct interventions: 43% and 31% underwent needling, respectively, and 50% of trabeculectomy eyes underwent laser suture lysis. There were 22 and 30 distinct complications, although most were transient. Ten percent and 5% underwent reoperation (P = 0.11). CONCLUSIONS: There was no detectable difference in risk of failure and safety profiles between standalone ab interno microstent with MMC and trabeculectomy with MMC.

Efficacy and Safety of Femtosecond Laser-Assisted Cataract Surgery Compared with Manual Cataract Surgery: A Meta-Analysis of 14 567 Eyes.

TOPIC: To investigate the efficacy and safety of femtosecond laser-assisted cataract surgery (FLACS) relative to manual cataract surgery (MCS). CLINICAL RELEVANCE: It is unclear whether FLACS is more efficacious and safe relative to MCS. METHODS: A literature search of MEDLINE, EMBASE, and Scopus from 2007 to March 2016 was conducted. Studies containing both FLACS and MCS arms that reported on relevant efficacy and/or safety parameters were included. Weighted mean differences (WMDs) and risk ratios (RRs) with 95% confidence intervals (CIs) were calculated. RESULTS: From 2802 screened articles, 14 567 eyes from 15 randomized controlled trials and 22 observational cohort studies were included. For primary visual and refractive outcomes, no statistically significant difference was detected between FLACS and MCS in uncorrected distance visual acuity (WMD, -0.02; 95% CI, -0.04 to 0.01; P = 0.19), corrected distance visual acuity (WMD, -0.01; 95% CI, -0.02 to 0.01; P = 0.26), and mean absolute error (WMD, -0.02; 95% CI, -0.07 to 0.04; P = 0.57). In terms of secondary surgical end points, there was a statistically significant difference in favor of FLACS over MCS for effective phacoemulsification time (WMD, -3.03; 95% CI, -3.80 to -2.25; P < 0.001), capsulotomy circularity (WMD, 0.16; 95% CI, 0.11-0.21; P < 0.001), postoperative central corneal thickness (WMD, -6.37; 95% CI, -11.88 to -0.86; P = 0.02), and corneal endothelial cell reduction (WMD, -55.43; 95% CI, -95.18 to -15.69; P = 0.006). There was no statistically significant difference between FLACS and MCS for total surgery time (WMD, 1.25; 95% CI, -0.08 to 2.59; P = 0.07), capsulotomy circularity using a second formula (WMD, 0.05; 95% CI, -0.01 to 0.12; P = 0.10), and corneal endothelial cell count (WMD, 73.39; 95% CI, -6.28 to 153.07; P = 0.07). As well, there was a significantly higher concentration of prostaglandins after FLACS relative to MCS (WMD, 198.34; 95% CI, 129.99-266.69; P < 0.001). Analysis of safety parameters revealed that there were no statistically significant differences in the incidence of overall complications between FLACS and MCS (RR, 2.15; 95% CI, 0.74 to 6.23; P = 0.16); however, posterior capsular tears were significantly more common in FLACS versus MCS (RR, 3.73; 95% CI, 1.50-9.25; P = 0.005). CONCLUSIONS: There were no statistically significant differences detected between FLACS and MCS in terms of patient-important visual and refractive outcomes and overall complications. Although FLACS did show a statistically significant difference for several secondary surgical outcomes, it was associated with higher prostaglandin concentrations and higher rates of posterior capsular tears.

Risk communication in cataract surgery.

PURPOSE: Risk communication is an integral aspect of shared decision-making and evidence-based patient choice. There is currently no recommended way of communicating risks and benefits of cataract surgery to patients. This study aims to investigate whether the way this information is presented influences patients' perception of how risky surgery will be. METHODS AND ANALYSIS: Two-arm parallel randomised study and patients referred for cataract surgery were assigned to receive information framed either positively (99% chance of no adverse effects) or negatively (1% chance of adverse effects). Subsequently, patients rated their perceived risk of experiencing surgical side effects on a 1-6 scale. RESULTS: This study included 100 patients, 50 in each study group. Median (IQR) risk perception was 2 (1-2) in the positive framing group and 3 (1-3) in the negative framing group (p<0.0001). Risk framing was the only factor that was significant in risk perception, with no differences found by other patient clinical or demographic characteristics. CONCLUSION: Patients who received positive framing reported lower risk scores for cataract surgery than patients who received negative framing. Patient factors were not identified as significant determinants in patients' perceived risk. Larger longitudinal studies are warranted to further investigate.

Association Between Sociodemographic Factors and Self-reported Glaucoma in the National Health Interview Survey: A Population-Based Analysis.

PURPOSE: To investigate the association between social determinants of health (SDH) in the domains of social and community context, education access, environmental context, economic stability, and healthcare access, with glaucoma prevalence. DESIGN: Cross-sectional study. METHODS: The study population consisted of adult participants who answered glaucoma-related questions on the 2017 National Health Interview Survey (NHIS), the most recent iteration that includes glaucoma-related questions. The main outcome measures included the relationships between SDH-related factors and self-reported glaucoma diagnosis as well as self-reported glaucomatous vision loss were examined using univariable and multivariable regression models. RESULTS: In total, 26,696 of 26,742 (99.83%) NHIS respondents were included, of whom 880 (3.30%) reported a glaucoma diagnosis and 275 (1.03%) reported glaucomatous vision loss. Participants were predominantly middle-aged (50.95 ± 18.60 years), female (54.75%), and non-Hispanic White (70.49%). In age-adjusted multivariable regression (n = 25,456), non-Hispanic Black race (odds ratio [OR] = 1.87, 99% CI = [1.37, 2.55], P < .001, compared to non-Hispanic White race) and poor health status (OR = 1.54, 99% CI = [1.00, 2.37], P = .01, compared to good health status) were significant predictors of glaucoma diagnosis. For glaucomatous vision loss, having an income below the poverty threshold (OR = 2.41, 99% CI = [1.12, 5.20], P = .003, compared to income ≥5 times the poverty threshold) was the only significant predictor in univariable analyses. No SDH-related factors were significantly associated with glaucomatous vision loss in multivariable analysis (n = 848). Multicollinearity was minimal (variation inflation factor<1.6 for all independent variables). CONCLUSIONS: Non-Hispanic Black race and poor health status were associated with self-reported glaucoma diagnosis. Physicians and policymakers may consider SDH when assessing clinical risk and designing public health interventions.

Eye protection following cataract surgery: a systematic review.

BACKGROUND: There is a high variability in the use of postoperative eye protection among ophthalmologists. Postoperative eye protection treatment modalities include an eye shield, an eye patch, an ocular bandage, and instant vision. The aim of this study was to review and compare the evidence on the various options for eye protection. METHODS: A systematic literature search was conducted, and original comparative articles that reported on subjective symptoms (e.g., foreign-body sensation, photophobia, tearing, and pain) and postoperative outcomes (e.g., tear film breakup time, best-corrected visual acuity, etc.) after usage of an eye protection method were included. RESULTS: Overall, 598 eyes across 8 articles were included. Included studies investigated ocular bandages (n = 6), eye patches (n = 4), instant vision (n = 2), and eye shields (n = 1) postoperatively. In 5 studies, patients receiving ocular bandages self-reported symptoms, including pain (n = 3), foreign-body sensation (n = 4), photophobia (n = 3), and tearing (n = 3), at a reduced or equivalent rate compared with other treatment modalities. With the ocular bandage, 3 studies reported increased tear film breakup time, and 1 study reported improvements in corneal wound healing compared with a control group. Two studies reported reduced tear film breakup time for the eye patch relative to the ocular bandage, and another study reported reduced tear film breakup time for instant vision compared with the eye patch. CONCLUSIONS: Patient-reported symptoms are acutely reduced for patients receiving an ocular bandage relative to instant vision following cataract surgery. Patients prefer receiving some form of postoperative protection as opposed to instant vision.

Preoperative evaluations for ophthalmic surgery: A systematic review of 48,869 eyes.

Eliminating low-yield testing can reduce the burden on modern health care systems. Our purpose is to determine whether routine preoperative assessment impacts the incidence of perioperative complications in ophthalmic surgery. We conducted a comprehensive search of Ovid MEDLINE, EMBASE, and Cochrane Library databases to identify studies investigating the incidence of perioperative complications following any preoperative assessment for patients undergoing ophthalmic surgery (PROSPERO ID#164008). Four randomized controlled trials (RCTs) and 5 observational studies were selected for inclusion. Risk of bias assessment revealed a lack of masking and insufficient statistical power in RCTs, and confounding in observational studies. Routine preoperative testing-including laboratory tests, electrocardiogram, and imaging studiesdid not decrease the incidence of adverse events or risk of perioperative ocular and systemic complications in most studies. Two cohort studies (1 retrospective, 1 prospective) suggestd that patients with certain preexisting health conditions were at increased risk for adverse events perioperatively. Another retrospective study found a lower risk of complications in high-risk patients who underwent evaluation. While patients with comorbidities may be at increased risk of adverse events, the role of preoperative assessment is not well delineated in this population. Further study is required to determine the comparative safety, effectiveness, and implementation of alternative assessment tools.

All Consecutive Ab Externo SIBS Microshunt Implantations With Mitomycin C: One-Year Outcomes and Risk Factors for Failure.

PURPOSE: To present the effectiveness, risk factors for surgical failure, and adverse events over 12 months in a consecutive diverse cohort of glaucoma patients who underwent solo or combined ab externo SIBS microshunt with mitomycin C (MMC) with or without previous subconjunctival surgery. DESIGN: Retrospective, consecutive, interventional case series. METHODS: Consecutive glaucomatous eyes on maximally tolerated medical therapy received ab externo SIBS microshunt with MMC implantation as a solo or combined procedure with phacoemulsification from July 2015 to January 2020. The primary outcome was the proportion of eyes at 12-months with the following: (1) no 2 consecutive intraocular pressures (IOPs) >17 mm Hg or clinical hypotony, without (complete success) or with (qualified success) glaucoma medications; and (2) ≥20% reduction from baseline IOP. Secondary outcomes included upper IOP thresholds of 14 and 21 mm Hg with and without a 20% IOP reduction from baseline, median IOP, medications, risk factors for failure, postoperative interventions, complications, and reoperations. RESULTS: A total of 436 eyes underwent surgery; 86 (20%) combined with phacoemulsification, 127 (29%) in eyes with refractory glaucoma, and 234 (51%) stand-alone procedures in non-refractory eyes. Complete success (6-17 mm Hg with no medications) was achieved in 64.0% of combined eyes, 58.1% of refractory eyes, and 74.8% of stand-alone non-refractory eyes; and qualified success rates (6-17 mm Hg with medications) were 90.7%, 84.7%, and 92.4% of eyes, respectively. At 12 months, 67% of eyes were medication free. Significant risk factors for failure included combined procedures in refractory eyes (hazard ratio [HR] = 3.2; 95% CI = 1.4-7.4), receiving <0.4 mg/mL of MMC (HR = 2.2; 95% CI = 1.6-3.1), refractory eyes (HR = 1.7; 95% CI = 1.2-2.5), combined procedures (HR = 1.6; 95% CI = 1.0-2.5), and each additional baseline medication class (HR = 1.3; 95% CI = 1.1-1.5). Postoperative complications occurred in 31% of eyes, and more often in those receiving ≥0.4 mg/mL MMC (odds ratio [OR] = 2.2, 95% CI 1.2-3.8). Needling occurred in 12% of eyes, with significantly higher frequency in refractory eyes (23%) and combined procedures (13%) compared to stand-alone (7%; P < .001). Revisions and reoperations occurred in 4% and 1.4% of eyes, respectively. CONCLUSIONS: The 1-year follow-up data from this large and diverse cohort support promising rates of qualified and complete surgical success with decreased medication burden and few postoperative complications and interventions. Combined phacoemulsification, refractory glaucoma, and receiving <0.4mg/mL MMC were associated with reduced surgical success rates.

Ab Externo SIBS Microshunt with Mitomycin C for Open-Angle Glaucoma: Three-Year Results as a Primary Surgical Intervention.

PURPOSE: To determine the effectiveness, risk factors for surgical failure, and adverse events in a large cohort of patients receiving stand-alone ab externo poly(styrene-block-isobutylene-block-styrene) (SIBS) microshunt implantation with mitomycin C (MMC) over 3 years of follow-up. DESIGN: Retrospective, interventional case series. PARTICIPANTS: Glaucomatous eyes on maximally tolerated medical therapy with no previous subconjunctival glaucoma surgery. METHODS: Records of eyes that underwent ab externo SIBS microshunt with MMC between July 2015 and November 2017 were reviewed. Data from all follow-up visits were utilized and included intraocular pressure (IOP), medication use, postoperative interventions, complications, and reoperations. MAIN OUTCOME MEASURES: The primary outcome was proportion of eyes at 3 years with (1) no 2 consecutive IOPs > 17 mmHg (or < 6 mmHg with > 2 lines of vision loss from baseline); (2) ≥ 20% reduction from baseline IOP; and (3) using no glaucoma medications (complete success). Secondary outcomes included 14 and 21 mmHg upper IOP thresholds with and without ≥ 20% IOP reduction from baseline, qualified success (with glaucoma medications), risk factors for failure, median IOP/medications, postoperative interventions, complications, and reoperations. RESULTS: One hundred fifty-two eyes from 135 patients were included. Complete and qualified success was achieved in 55.6% and 74.8% of eyes, respectively. Time to first glaucoma medication use was a median of 16.9 (interquartile range [IQR], 12.1-34.1) months; however, 59.4% of eyes remained medication free at 3 years. Significant risk factors for failure included receiving < 0.4 mg/ml of MMC (adjusted hazard ratio [HR], 2.42; 95% confidence interval [CI], 1.44-4.05) and baseline IOP < 21 mmHg (adjusted HR, 1.79; 95% CI, 1.03-3.13). The most common complications were choroidal detachment, hyphema, and anterior chamber shallowing, occurring in 7%, 5%, and 5% of eyes, respectively. The needling rate was 15.1%, with significantly higher frequency for baseline IOP > 21 mmHg (HR, 3.21; 95% CI, 1.38-7.48). Revisions occurred in 7% of eyes and reoperations in 2.6%. Eyes receiving < 0.4 mg/ml of MMC underwent more revisions (odds ratio, 4.9; 95% CI, 1.3-18.3). CONCLUSIONS: Three-year follow-up data from this large cohort continues to support promising rates of qualified and complete success, with decreased medication burden postoperatively and few postoperative complications and interventions. Comparisons to other filtering surgeries will further facilitate integration of the SIBS microshunt into the surgical treatment paradigm. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Gonioscopy-assisted transluminal trabeculotomy is an effective surgical treatment for uveitic glaucoma.

BACKGROUND: To assess the efficacy and safety of gonioscopy-assisted transluminal trabeculotomy (GATT) in uveitic glaucoma (UG). METHODS: A retrospective interventional case series in which 33 eyes of 32 patients with UG underwent GATT with or without concomitant cataract extraction and intraocular lens implantation (CE/IOL) at three Canadian treatment centres from October 2015 to 2020. The main outcome measure was surgical success defined as an intraocular pressure (IOP) ≤18 mm Hg and at least one of the following: IOP within one mm Hg of baseline on fewer glaucoma medications as compared with baseline or a 30% IOP reduction from baseline on the same or fewer medications. Secondary outcome measures were IOP, medication usage and surgical complications. RESULTS: Mean patient age (mean±SD) was 49±16 years (range: 18-79) and 44% were female. GATT was performed as a standalone procedure in 52% of cases and the remainder were combined with CE/IOL. Surgical success was achieved in 71.8% (SE: 8.7%) of cases. Mean preoperative IOP (±SD) was 31.4±10.8 mm Hg on a median of 4 medications. 59% of patients were on oral carbonic anhydrase inhibitors (CAIs) prior to surgery. After 1 year, average IOP was 13.8 mm Hg on a median 1 medication, with 6% of patients being on oral CAIs. No sight threatening complications occurred during surgery or follow-up. CONCLUSION: GATT is an effective surgical strategy in the management of UG. This microinvasive conjunctival-sparing procedure should be considered early in these patients.

Segmental Suture Gonioscopy-Assisted Transluminal Trabeculotomy: Comparison of Superior Versus Inferior Hemisphere Outcomes.

PRCIS: Analysis of efficacy, safety, and risk factors for failure of superior versus inferior 180-degree segmental gonioscopy-assisted transluminal trabeculectomy showed no significant difference between approaches, with novel risk factors for failure identified. PURPOSE: Compare the efficacy, safety, and risk factors for failure of superior versus inferior 180-degree segmental suture gonioscopy-assisted transluminal trabeculotomy (GATT). DESIGN: Multicenter, retrospective interventional cohort study of 297 eyes of 243 glaucomatous patients, which underwent superior or inferior 180-degree suture hemi-GATT surgery combined with phacoemulsification at one of 3 Canadian ophthalmological surgical centres in Calgary, Alberta or Toronto, Ontario. MAIN OUTCOME MEASURES: The primary outcome measure was the hazard ratio (HR) of failure for the "primary success" criteria. "Primary success" was defined as an intraocular pressure (IOP) <18 mm Hg and either 1) IOP reduced by ≥20% from baseline on the same number of IOP-lowering medications or 2) IOP ≤ baseline on fewer medications. Secondary outcome measures included HRs of failure for alternative criteria ("complete success", "qualified success" and "20% IOP reduction"), cross-sectional analysis, and Cox proportional hazard analysis for risk factors associated with increased failure for the complete cohort. RESULTS: Baseline characteristics were similar between groups. The crude and adjusted HR of failure for the "primary success" criteria for superior surgeries relative to inferior surgeries were 1.27 (95% CI = 0.86-1.88) and 1.50 (95% CI = 0.91-2.46), with no statistically significant difference between approaches. Of the secondary criteria, there was statistical significance in favor of inferior surgeries only for crude analysis of the "20% reduction" criteria (1.40/1.27 (95% CI = 1.01-1.92). Increased risk of failure by the "primary success" measure for either intervention was seen with primary open angle glaucoma, advanced disease, and age below 70 years. There were no significant differences in the frequency of postoperative complications between cohorts, which were present in 72 superior (44.4%) and 67 inferior (49.6%; P value = 0.41) eyes; mostly early postoperative hyphema, iritis, and corneal edema. CONCLUSIONS: This retrospective study showed no difference in inferior versus superior 180 degrees of hemi-GATT/phacoemulsification cataract surgeries through the majority of analyses. Nonmodifiable factors including glaucoma type, advanced disease, and younger age were associated with a significantly higher risk of failure in this cohort. Further study is warranted.

The Cataract Surgery Learning Curve: Quantitatively Tracking a Single Resident's Operative Actions Throughout Their Training.

PURPOSE: To track operative phases of cataract surgery over a resident's training to measure action times and frequencies as a surrogate for competency and skill progression. DESIGN: An n = 1 panel study. METHODS: Cataract surgery video recordings performed by a single resident between 2021-2022 were collected. Only full-length videos of adequate quality without supervisor intervention were included. The start and end times of 19 distinct operative phases of cataract surgery were manually labeled by a trained annotator. Timeseries analysis was employed to measure the direction and magnitude of trends in the resident's surgical timing for each action across their first year of training. RESULTS: The dataset comprised 100 videos spread across the resident's sixth to 760th cases. The median total time was 11.6 minutes (IQR 10.1-14.4 minutes), with overall speed increasing at a rate of 43.4 seconds for every 10 videos (95% CI 35.1, 52.7 seconds). Nine operative phases significantly decreased in time throughout training. The main incision, phacoemulsification, and hydrodissection had the greatest improvements in speed relative to their average procedural time. There was an average of 26.9 distinct operative actions (excluding idle periods) in each video (range 20-50). CONCLUSIONS: This is the first study to quantitatively track operative times and frequencies across all relevant actions in cataract surgery and derive learning curves for each. Consistent with previous works, it was found that a basic level of surgical competency was achieved after performing 80 cases. In addition, results from this study indicated that the next level in skill advancement towards surgical finesse occurs after 300 cases.