Nontraditional approaches to sedation for anterior segment surgery: a narrative review.

PURPOSE OF REVIEW: Surgical and anesthetic technological advancement have made both cataract and noncataract anterior segment surgery significantly less invasive and time-intensive, facilitating the transition of some of these procedures from the operating room under monitored anesthesia care (MAC) to the office-based setting without MAC. This transition has been aided by the popularization of nonintravenous approaches to achieving patient sedation for these procedures. In this review, we discuss the literature surrounding traditional and nontraditional methods of achieving patient sedation for anterior segment surgery. RECENT FINDINGS: Our survey of the literature suggests that nonintravenous (IV) approaches to sedation for these procedures may be just as safe, effective, and satisfactory to patients as traditional IV approaches. SUMMARY: As anterior segment surgery becomes less invasive and less time-intensive, providers considering transitioning their cataract and anterior segment surgery out of the operating room and into the office-based setting without MAC anesthesia should consider the non-IV sedation options outlined in this review to achieve adequate patient sedation and comfort.

Comparison of Machine and Human Expert Evaluation of Capsulorrhexis Creation Performance Through Analysis of Surgical Video Recordings.

Purpose: Achieving competency in cataract surgery is an essential component of ophthalmology residency training. Video-based analysis of surgery can change training through its objective, reliable, and timely assessment of resident performance. Methods: Using the Image Labeler application in MATLAB, the capsulorrhexis step of 208 surgical videos, recorded at the University of Michigan, was annotated for subjective and objective analysis. Two expert surgeons graded the creation of the capsulorrhexis based on the International Council of Ophthalmology's Ophthalmology Surgical Competency Assessment Rubric:Phacoemulsification (ICO-OSCAR:phaco) rating scale and a custom rubric (eccentricity, roundness, size, centration) that focuses on the objective aspects of this step. The annotated rhexis frames were run through an automated analysis to obtain objective scores for these components. The subjective scores were compared using both intra and inter-rater analyses to assess the consistency of a human-graded scale. The subjective and objective scores were compared using intraclass correlation methods to determine relative agreement. Results: All rhexes were graded as 4/5 or 5/5 by both raters for both items 4 and 5 of the ICO-OSCAR:phaco rating scale. Only roundness scores were statistically different between the subjective graders (mean difference = -0.149, p-value = 0.0023). Subjective scores were highly correlated for all components (>0.6). Correlations between objective and subjective scores were low (0.09 to 0.39). Conclusion: Video-based analysis of cataract surgery presents significant opportunities, including the ability to asynchronously evaluate performance and provide longitudinal assessment. Subjective scoring between two raters was moderately correlated for each component.

Evaluation of Methods for Detection and Semantic Segmentation of the Anterior Capsulotomy in Cataract Surgery Video.

Background: The capsulorhexis is one of the most important and challenging maneuvers in cataract surgery. Automated analysis of the anterior capsulotomy could aid surgical training through the provision of objective feedback and guidance to trainees. Purpose: To develop and evaluate a deep learning-based system for the automated identification and semantic segmentation of the anterior capsulotomy in cataract surgery video. Methods: In this study, we established a BigCat-Capsulotomy dataset comprising 1556 video frames extracted from 190 recorded cataract surgery videos for developing and validating the capsulotomy recognition system. The proposed system involves three primary stages: video preprocessing, capsulotomy video frame classification, and capsulotomy segmentation. To thoroughly evaluate its efficacy, we examined the performance of a total of eight deep learning-based classification models and eleven segmentation models, assessing both accuracy and time consumption. Furthermore, we delved into the factors influencing system performance by deploying it across various surgical phases. Results: The ResNet-152 model employed in the classification step of the proposed capsulotomy recognition system attained strong performance with an overall Dice coefficient of 92.21%. Similarly, the UNet model with the DenseNet-169 backbone emerged as the most effective segmentation model among those investigated, achieving an overall Dice coefficient of 92.12%. Moreover, the time consumption of the system was low at 103.37 milliseconds per frame, facilitating its application in real-time scenarios. Phase-wise analysis indicated that the Phacoemulsification phase (nuclear disassembly) was the most challenging to segment (Dice coefficient of 86.02%). Conclusion: The experimental results showed that the proposed system is highly effective in intraoperative capsulotomy recognition during cataract surgery and demonstrates both high accuracy and real-time capabilities. This system holds significant potential for applications in surgical performance analysis, education, and intraoperative guidance systems.

Baseline Participant Characteristics at Enrollment in the Zoster Eye Disease Study.

PURPOSE: The Zoster Eye Disease Study (ZEDS) is the first randomized clinical trial to study the efficacy of long-term (1 year) suppressive valacyclovir treatment on herpes zoster ophthalmicus (HZO) outcomes. This article details the baseline characteristics of participants. SETTING: The study was set at 95 participating clinical centers in 33 states, Canada, and New Zealand. STUDY POPULATION: Immunocompetent adults with a history of a characteristic HZO unilateral rash and documentation of an episode of active dendriform epithelial keratitis, stromal keratitis, endothelial keratitis, or iritis within the preceding year, enrolled in ZEDS from November 2017 to January 2023. INTERVENTION: Participants were randomized to double-masked oral valacyclovir 1 gm daily versus placebo for 1 year of treatment and followed for 18 months. RESULTS: Five hundred twenty-seven participants were enrolled across 4 strata according to age at HZO onset (younger or older than 60 years) and duration of HZO at enrollment (less or greater than 6 months), with an even distribution of men and women and a median age of 60 years. More participants with recent (57%, 300/527) than chronic HZO and younger than 60 years at HZO onset (54%, 286/527) were enrolled. Most participants were treated acutely with a recommended antiviral regimen (91%, 480/527) and had not been vaccinated against zoster (79%, 418/527). CONCLUSIONS: The broad ZEDS study population enhances the likelihood that ZEDS will provide generalizable high-quality evidence regarding the efficacy and safety of suppressive valacyclovir for HZO immunocompetent adults and whether it should become standard of care. TRIAL REGISTRATION: ClinicalTrials.gov Identifier: NCT03134196.

Severe Spontaneous Tilt of Scleral-Fixated Intraocular Lenses.

PURPOSE: To report and evaluate a multicenter series of 18 cases of severe, spontaneous IOL tilt involving the flanged intrascleral haptic fixation technique (FISHF). DESIGN: Clinical study with historical controls. METHODS: We report a cross-sectional study of 46 FISHF cases using the CT Lucia 602 IOL at a single academic center over a period of 24 weeks to determine the incidence of severe rotisserie-style rotational tilt. These rates were then compared with the same time-frame the prior year to help determine if this is a new phenomenon. Additional cases of severe tilt were solicited from another 4 academic centers. RESULTS: Among 46 FISHF cases at a single center, 5 developed severe tilt. No clear pattern in surgical technique, ocular history, or ocular anatomy was evident in these cases compared with controls, although the involved IOLs clustered within a narrow diopter range, indicative of a batch effect. In the same 24-week interval the year before, 33 FISHF cases were performed, none of which exhibited severe rotational tilt. In our multicenter dataset, 18 cases of tilt were identified. Surgeons included fellow and early-career physicians as well as surgeons with multiple years of experience with the Yamane technique. A variety of surgical approaches for FISHF were represented. In at least 8 of the cases, haptic rotation and/or dehiscence at the optic-haptic junction were documented. CONCLUSIONS: The identification of haptic rotation and dehiscence intraoperatively in several cases may reflect a new stability issue involving the optic-haptic junction.

Factors Associated With Laboratory Test Negativity Following a Transition in Specimen Collection in Microbial Keratitis Cases.

PURPOSE: Negative laboratory results make targeting microbial keratitis treatment difficult. We investigated factors associated with laboratory negativity in patients with microbial keratitis in the context of a transition to a new specimen collection method. METHODS: Microbial keratitis patients with associated laboratory tests were identified in the electronic health record of a tertiary care facility from August 2012 to April 2022. Patient demographics and laboratory results were obtained. Random sampling of 50% of charts was performed to assess the impact of the ocular history and pretreatment measures. The relationship between probability of negative laboratory results with demographics, ocular history, pretreatment measures, and utilization of a new specimen collection method (i.e. ESwab) was evaluated by multivariable logistic regression. RESULTS: Of 3395 microbial keratitis patients identified, 31% (n = 1051) had laboratory tests. Laboratory testing increased over time (slope = 2.5% per year, p < 0.001; 19.6% in 2013 to 42.2% in 2021). Laboratory negative rate increased over time (slope = 2.2% per year, p = 0.022; 48.5% in 2013 to 62.3% in 2021). Almost one-third of patients (31.2%, n = 164) were pretreated with steroids. Over two-thirds of patients were pretreated with antibiotics (69.5%, n = 367). 56.5% (n = 297) of patients were outside referrals. In multivariable regression, patients with corticosteroid pretreatment had lower odds of negative laboratory results (odds ratio [OR] = 0.49, p = 0.001). There were higher odds of negative laboratory results for every additional antibiotic prescribed to a patient prior to presentation (OR = 1.30, p = 0.006) and for specimens collected using ESwabs (OR = 1.69, p = 0.005). Age, prior eye trauma, outside referrals, and contact lens wear were not significantly associated with negative laboratory results. CONCLUSION: More microbial keratitis associated laboratory tests are being taken over time. Over 60% of tests were negative by 2022. Factors associated with negative laboratory test results included pretreatment with antibiotics and specimens collected with the new collection method.

A Comparison of Culture Results and Visual Acuity in Contact Lens Related Microbial Keratitis.

PURPOSE: Evaluate the effect of corneal and contact lens-related (CLR) culture results on visual acuity (VA) in patients with microbial keratitis (MK). METHODS: MK patients with corneal and CLR cultures were identified in the University of Michigan electronic health record from August 2012 to April 2022. Test results were classified as laboratory-positive or laboratory-negative. Linear regression was used to examine trends of VA and associations between changes in VA (differences of VA at 90-day and baseline VA) and corneal and CLR culture results, after adjustment for baseline VA. One-sample t-tests were used to test if the slope estimates were different from zero. RESULTS: MK patients (n = 50) were on average 49 years old (standard deviation = 20.9), 56% female, and 90% White. Positive corneal and CLR cultures were reported in 60% and 64% of patients, respectively, and 38% reported both. The agreement rate between corneal and CLR culture results was 30% (n = 15/50). LogMAR VA improved over time in patients with positive corneal and CLR cultures (Estimate=-0.19 per 10-day increase, p = 0.002), and in those with negative corneal and positive CLR cultures (Estimate= -0.17 per 10-day increase, p = 0.004). Compared to patients with negative corneal and CLR cultures, there was a trend toward improvement in VA for patients with positive corneal and CLR cultures (Estimate=-0.68, p = 0.068), and those with negative corneal and positive CLR cultures (Estimate= -0.74, p = 0.059), after adjusting for baseline VA. CONCLUSIONS: Positive CLR cultures are associated with significant improvement in VA over time. These additional cultures can provide guidance on appropriate antimicrobial selection, especially when corneal cultures are negative.

Adaptive Tensor-Based Feature Extraction for Pupil Segmentation in Cataract Surgery.

Cataract surgery remains the only definitive treatment for visually significant cataracts, which are a major cause of preventable blindness worldwide. Successful performance of cataract surgery relies on stable dilation of the pupil. Automated pupil segmentation from surgical videos can assist surgeons in detecting risk factors for pupillary instability prior to the development of surgical complications. However, surgical illumination variations, surgical instrument obstruction, and lens material hydration during cataract surgery can limit pupil segmentation accuracy. To address these problems, we propose a novel method named adaptive wavelet tensor feature extraction (AWTFE). AWTFE is designed to enhance the accuracy of deep learning-powered pupil recognition systems. First, we represent the correlations among spatial information, color channels, and wavelet subbands by constructing a third-order tensor. We then utilize higher-order singular value decomposition to eliminate redundant information adaptively and estimate pupil feature information. We evaluated the proposed method by conducting experiments with state-of-the-art deep learning segmentation models on our BigCat dataset consisting of 5,700 annotated intraoperative images from 190 cataract surgeries and a public CaDIS dataset. The experimental results reveal that the AWTFE method effectively identifies features relevant to the pupil region and improved the overall performance of segmentation models by up to 2.26% (BigCat) and 3.31% (CaDIS). Incorporation of the AWTFE method led to statistically significant improvements in segmentation performance (P < 1.29 × 10-10 for each model) and yielded the highest-performing model overall (Dice coefficients of 94.74% and 96.71% for the BigCat and CaDIS datasets, respectively). In performance comparisons, the AWTFE consistently outperformed other feature extraction methods in enhancing model performance. In addition, the proposed AWTFE method significantly improved pupil recognition performance by up to 2.87% in particularly challenging phases of cataract surgery.

CatStep: Automated Cataract Surgical Phase Classification and Boundary Segmentation Leveraging Inflated 3D-Convolutional Neural Network Architectures and BigCat.

Objective: Accurate identification of surgical phases during cataract surgery is essential for improving surgical feedback and performance analysis. Time spent in each surgical phase is an indicator of performance, and segmenting out specific phases for further analysis can simplify providing both qualitative and quantitative feedback on surgical maneuvers. Study Design: Retrospective surgical video analysis. Subjects: One hundred ninety cataract surgical videos from the BigCat dataset (comprising nearly 4 million frames, each labeled with 1 of 11 nonoverlapping surgical phases). Methods: Four machine learning architectures were developed for segmentation of surgical phases. Models were trained using cataract surgical videos from the BigCat dataset. Main Outcome Measures: Models were evaluated using metrics applied to frame-by-frame output and, uniquely in this work, metrics applied to phase output. Results: The final model, CatStep, a combination of a temporally sensitive model (Inflated 3D Densenet) and a spatially sensitive model (Densenet169), achieved an F1-score of 0.91 and area under the receiver operating characteristic curve of 0.95. Phase-level metrics showed considerable boundary segmentation performance with a median absolute error of phase start and end time of just 0.3 seconds and 0.1 seconds, respectively, a segmental F1-score @70 of 0.94, an oversegmentation score of 0.89, and a segmental edit score of 0.92. Conclusion: This study demonstrates the feasibility of high-performance automated surgical phase identification for cataract surgery and highlights the potential for improved surgical feedback and performance analysis. Financial Disclosures: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Tensor-based Feature Extraction for Pupil Recognition in Cataract Surgery.

Cataract surgery remains the definitive treatment for cataracts, which are a major cause of preventable blindness worldwide. Adequate and stable dilation of the pupil are necessary for the successful performance of cataract surgery. Pupillary instability is a known risk factor for cataract surgery complications, and the accurate segmentation of the pupil from surgical video streams can enable the analysis of intraoperative pupil changes in cataract surgery. However, pupil segmentation performance can suffer due to variations in surgical illumination, obscuration of the pupil with surgical instruments, and hydration of the lens material intraoperatively. To overcome these challenges, we present a novel method called tensor-based pupil feature extraction (TPFE) to improve the accuracy of pupil recognition systems. We analyzed the efficacy of this approach with experiments performed on a dataset of 4,560 intraoperative annotated images from 190 cataract surgeries in human patients. Our results indicate that TPFE can identify features relevant to pupil segmentation and that pupil segmentation with state-of-the-art deep learning models can be significantly improved with the TPFE method.

Perception of Race and Sex Diversity in Ophthalmology by Artificial Intelligence: A DALL E-2 Study.

Purpose: In the past few years, there has been remarkable progress in accessibility of open-source artificial intelligence (AI) image generators, developed to help humans understand how AI sees our world. Here, we characterize perception of racial and sex diversity in ophthalmology by AI. Methods: OpenAI's open-source DALL E-2 AI was used for image generation of ophthalmologists with queries that all included "American" and "portrait photo". Factors used for queries contained categories of following: "Positive Characteristic", "Negative Characteristic", "Finances", "Region", "Experience", "Academic Rank", and "Subspecialty". The first 40 faces for each search were categorized on the basis of race and sex by two independent reviewers. If race or sex was not agreed upon, a third reviewer independently provided a classification, or if still indeterminate, the image was labeled as such. Images that did not adequately show facial features were excluded from categorization. Results: A total of 1560 images were included in the analysis. Control search queries specifying solely ophthalmologist sex and/or race outputted (100%) accurate images validating the tool. The query "American ophthalmologist, portrait photo" portrayed the majority of ophthalmologists as White (75%) and male (77.5%). Young/inexperienced/amateur ophthalmologists were perceived to have greater non-White racial diversity (27.5%) and female representation (28.3%) relative to old/experienced/mature ophthalmologists (23.3% non-White and 18.3% female). Ophthalmology department chairs (25%) had slightly more racial diversity compared to residents (22.5%), but residents had greater female representation (30%) compared to chairs (15%). Conclusion: Our results suggest the DALL E-2 AI may perceive a trend of increasing racial and sex diversity in younger, newer ophthalmologists compared to more senior ophthalmologists. Future investigations should attempt to validate how AI may be used as a tool to evaluate ophthalmology's progress towards becoming more inclusive of increasingly diverse ophthalmologists.

The Cost of Standard and Complex Pars Plana Vitrectomy for Retinal Detachment Repair Exceeds Its Reimbursement.

OBJECTIVE: To measure the total costs and reimbursements associated with standard and complex pars plana vitrectomy using time-driven activity-based costing (TDABC). DESIGN: Economic analysis at a single academic institution. SUBJECTS: Patients who underwent standard or complex pars plana vitrectomy (PPV; Current Procedural Terminology codes 67108 and 67113) at the University of Michigan in the calendar year 2021. METHODS: Process flow mapping for standard and complex PPVs was used to determine the operative components. The internal anesthesia record system was used to calculate time estimates, and financial calculations were constructed from published literature and internal sources. A TDABC analysis was used to determine the costs of standard and complex PPVs. Average reimbursement was based on Medicare rates. MAIN OUTCOME MEASURES: The primary outcomes were the total costs for standard and complex PPVs and the resulting net margin at current Medicare reimbursement levels. The secondary outcomes were the differential in surgical times, costs, and margin for standard and complex PPV. RESULTS: Over the 2021 calendar year, a total of 270 standard and 142 complex PPVs were included in the analysis. Complex PPVs were associated with significantly increased anesthesia time (52.28 minutes; P < 0.001), operating room time (51.28 minutes; P < 0.0001), surgery time (43.64 minutes; P < 0.0001), and postoperative time (25.95 minutes; P < 0.0001). The total day-of-surgery costs were $5154.59 and $7852.38 for standard and complex PPVs, respectively. Postoperative visits incurred an additional cost of $327.84 and $353.86 for standard and complex PPV, respectively. The institution-specific facility payments were $4505.50 and $4935.14 for standard and complex PPV, respectively. Standard PPV yielded a net negative margin of -$976.93, whereas complex PPV yielded a net negative margin of -$3271.10. CONCLUSIONS: This analysis demonstrated that Medicare reimbursement is inadequate in covering the costs of PPV for retinal detachment, with a particularly large negative margin for more complex cases. These findings demonstrate that additional steps may be necessary to mitigate adverse economic incentives so that patients continue to have timely access to care to achieve optimal visual outcomes after retinal detachment. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

Cost Drivers of Endothelial Keratoplasty: A Time-Driven Activity-Based Costing Analysis.

PURPOSE: To determine cost drivers of endothelial keratoplasty (EK) through evaluation of surgical costs and procedure length based on type of EK, use of preloaded grafts, and performance of simultaneous cataract surgery. DESIGN: This study was an economic analysis of EKs at a single academic institution using time-driven activity-based costing (TDABC) methodology. PARTICIPANTS: Endothelial keratoplasty surgical cases, including Descemet membrane endothelial keratoplasty (DMEK) and Descemet stripping automated endothelial keratoplasty (DSAEK), at the University of Michigan Kellogg Eye Center from 2016 to 2018 were included in the analysis. METHODS: Data and inputs were obtained via the electronic health record (EHR) and from prior literature. Simultaneous cataract surgeries were included and separately categorized for analysis. Endothelial keratoplasty expenses were determined with TDABC, a method for cost calculation that incorporates the time that key resources are used and each resource's associated cost rate. MAIN OUTCOME MEASURES: Main outcome measures included surgery length (in minutes) and day-of-surgery costs. RESULTS: There were 559 EKs included: 355 DMEKs and 204 DSAEKs. Fewer DSAEKs had simultaneous cataract extraction (47; 23%) than DMEK (169; 48%). Of the DMEKs, 196 (55%) used preloaded corneal grafts. Descemet membrane endothelial keratoplasty cost $392.31 less (95% confidence interval, $251.05-$533.57; P < 0.0001) than DSAEK and required 16.94 fewer minutes (14.16-19.73; P < 0.0001). Descemet membrane endothelial keratoplasty cases that used preloaded corneal grafts cost $460.19 less ($316.23-$604.14; P < 0.0001) and were 14.16 minutes shorter (11.39-16.93; P < 0.0001). In multivariate regression, preloaded graft use saved $457.19, DMEK (compared with DSAEK) saved $349.97, and simultaneous cataract surgery added $855.17 in day-of-surgery costs. CONCLUSIONS: Cost analysis of TDABC identified a day-of-surgery cost and surgical time reduction associated with the use of preloaded grafts for DMEK, DMEK compared with DSAEK, and isolated EK compared with EK combined with cataract surgery. This study provides an improved understanding of surgical cost drivers and margin incentivization, which may explain trends and indirectly influence patient care decisions in cornea surgery practices. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Clinical outcomes of prestripped, prestained, and preloaded Descemet's membrane endothelial keratoplasty ("P3 DMEK").

PURPOSE: Despite faster healing and reduced risk of rejection, some surgeons are hesitant to adopt Descemet membrane endothelial keratoplasty (DMEK) due to difficult intraoperative tissue preparation. Use of eye bank prestripped, prestained, and preloaded (p3) DMEK tissue can reduce the learning curve and risk of complications. MATERIALS AND METHODS: We conducted a prospective study including 167 eyes undergoing p3 DMEK and compared outcomes to a retrospective chart review of 201 eyes that underwent standard DMEK surgery. The primary outcomes were graft failure, detachment, and re-bubbling frequency. The secondary outcomes included baseline and postoperative visual acuity at months 1, 3, 6, and 12. Baseline and postoperative central corneal thickness (CCT) and endothelial cell counts (ECC) were collected. RESULTS: ECC decrease for p3 DMEK at 3, 6, and 12 months were 15.0%, 18.0%, and 21.0%, respectively. Forty (24%) of p3 DMEK and 72 (35.8%) of standard DMEK eyes had at least a partial graft detachment. There was no difference in CCT, graft failures, or re-bubble frequency. At 6 months, mean visual acuity was 20/26 and 20/24 for standard and p3 DMEK, respectively. Mean case time for p3 DMEK with phaco or p3 DMEK alone was 33 and 24 min, respectively. Mean case time for eyes undergoing DMEK with phaco or DMEK alone was 59 and 45 min, respectively. CONCLUSION: P3 DMEK tissue is safe and can provide excellent clinical outcomes that are comparable to standard DMEK tissue. Eyes undergoing p3 DMEK may have lower graft detachment and ECC loss.