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Purpose To evaluate the safety and efficacy of staged ultraviolet A (UVA) cross-linking following intrastromal 0.1% riboflavin administration in eyes with advanced corneal edema. Methods Ten eye bank corneas divided in two groups (n=5) were placed on a pressurized artificial anterior chamber following Descemet's membrane stripping. Two consecutive corneal pockets (350- and 150-µm depth) were sequentially created using a femtosecond laser. Sequential intrastromal injections of 0.1% riboflavin (0.2 mL) followed by either UVA irradiation (15 mW/cm2) for 7 minutes or exposure to air were performed for each pocket. Corneal clarity and central thickness were measured before and after the two UVA cross-linking steps. The same steps were clinically applied in an 84-year-old woman with bullous keratopathy prior to corneal transplantation and followed for 6 months. Results The corneal clarity improved in the treated but not the control eyes. The mean central corneal thickness was significantly reduced by 256 µm (ultrasound, P=.0002) and 273 µm (Scheimpflug, P=.0004) in treated eyes, but only 100 µm (ultrasound, P=.048) and 107 µm (Scheimpflug, P=.075) in the control eyes. The clinical treatment of corneal edema showed improved clarity and reduced central corneal thickness from 675 to 550 µm (ultrasound) and 696 to 571 µm (Scheimpflug) at 1 month. Best spectacle-corrected visual acuity improved from finger counting to 20/80 at 1 week and beyond, postponing corneal transplantation for >6 months. Conclusions Staged UVA cross-linking (15 mW/cm2) with femtosecond laser facilitated intrastromal 0.1% riboflavin administration may be a safe (no corneal scarring) and effective (marked reduction of edema) temporizing alternative method for managing bullous keratopathy. [J Refract Surg. 2008;24:S730–S736.]

Purpose: To determine how changes in corneal elasticity/stiffness might influence intraocular pressure (IOP) readings in diabetic patients. Methods: A systematic review of the literature was performed to understand the conflicting relationship between diabetes, elevated IOP, and glaucoma progression. Results: Diabetic patients have been found to have statistically significant higher IOP readings in some population-based studies compared to non-diabetics. Insulin resistance states, hyperglycemia and glycosylated hemoglobin have been correlated with higher IOP (1 mmHg) measurements in diabetic patients. In the Ocular Hypertension Treatment Study (OHTS), a self reported history of diabetes was found to be protective against the progression of primary open-angle glaucoma. Small differences in IOP measurements in diabetic patients may be due to corneal stiffening, as demonstrated by the protective effect of glucose-mediated collagen cross-linking against the manifestation and keratometric progression of keratoconus. Different collagen cross-linking agents may induce different degrees of corneal stiffening, which can result in differences in measured IOP. Conclusions: Glucose-mediated corneal stiffening due to collagen cross-linking might be responsible for IOP overestimation in diabetic patients. Corneal stiffening might explain why diabetic eyes tend to have higher IOP readings in large population-based studies and why those with ocular hypertension have a reduced risk for glaucoma progression. [J Refract Surg. 2007;23:85–88.]

Purpose To investigate comparative stiffness values in porcine corneas after standard cross-linking and a new, rapid method of cross-linking (flash-linking) using surface wave elastometry. Methods Ten porcine eyes were treated using an ultraviolet A (UVA) double diode light source with a wavelength of 370 nm and delivering an irradiance of 4.2 mW/cm2 at a distance of 1.2 cm while applying 0.1% riboflavin-5-phosphate drops to the central cornea every 5 minutes as a photosensitizer for 30 minutes (riboflavin-UVA group). The next 10 porcine corneas were treated with a single application of a customized photoactive cross-linking agent and 30 seconds of UVA light at the same power and wavelength (flash-linking group). Following treatment, the Sonic Eye system (PriaVision Inc) was used to measure ultrasound surface wave propagation time between two fixed-distance transducers applied to the cornea along central horizontal and vertical positions. Intraocular pressure was continuously monitored. Results Mean surface wave velocity was determined from the last 5 of 10 sequential measurements for each eye, and was 90.87±15.26 m/s for all eyes with a mean standard deviation (SD) of 2.34 m/s among each eye in the riboflavin-UVA group versus 83.66±12.30 m/s with a mean SD of 2.69 m/s among each eye in the flash-linking group before treatment and 109.2±21.76 m/s with a mean SD of 2.15 m/s among each eye (riboflavin-UVA group) versus 109.2±18.42 m/s with a mean SD of 2.26 m/s among each eye (flash-linking group) after cross-linking. The mean surface wave velocity increased by 18.3 units from 90.87 to 109.2 m/s (P=.003) after cross-linking with riboflavin-UVA, and by 25.5 m/s from 83.66 to 109.2 m/s (P=.0001) after flash-linking. Surface wave velocity was noted to increase after both cross-linking techniques, but the differences observed did not reach statistical significance (P=.74). Conclusions A new, rapid method of cross-linking (flash-linking) is introduced by the use of a customized photoactive cross-linking agent. The method demonstrates similar efficacy in stiffening the cornea (when measured with surface wave elastometry) in comparison to standard cross-linking, but requires only 30 seconds of UVA exposure. [J Refract Surg. 2008;24:S748–S751.]

Over the past few years the rat has gained prominence as an animal model for the study of glaucoma. However, no systematic study of the angle structures and the effects of medications on angle anatomy in the rat has been reported to date. We investigated the normal rat anterior segment anatomy in vivo using ultrasound biomicroscopy (UBM) and determined the effect of both cholinergic and anticholinergic medications on angle structures. Fourteen eyes of seven 2-month-old female Wistar rats were imaged using an ultrasound biomicroscope and a modified eyecup. Baseline measurements of the anterior chamber depth (ACD), trabecular-iris angle (TIA), iris thickness at the thickest point near the pupillary margin (IT), angle-opening distance (AOD) (distance between the posterior corneal surface and anterior iris surface measured at 200 microm from the scleral spur), corneal thickness (CT) and irido-zonular distance (IZD) were obtained. Imaging was repeated 30 min after instillation of one drop of cyclopentolate 1% and 48 h later 30 min after pilocarpine 1% instillation. The same measurements were obtained and compared to baseline values. Baseline values for all parameters recorded were not significantly different among contralateral eyes. After instillation of either pilocarpine or cyclopentolate, ACD was the only parameter that did not change significantly from baseline. In contrast, TIA, AOD, IZD, and IT were significantly different among the three groups. Post-hoc analysis (Bonferroni test) revealed differences among all three groups of eyes for TIA and AOD. A difference was also found between the pilocarpine-treated group and the other two groups for IZD and IT. A very small difference detected between the pilocarpine-treated group and the baseline measurements for CT was caused by the zero variance of measurements in the former group. Although both pilocarpine and cyclopentolate induced angle narrowing, inspection of the ultrasonic images revealed a differential effect. Pilocarpine caused a \"pupillary block-like\" picture, while cyclopentolate caused crowding of the iris base in the angle. Baseline characteristics of the normal rat anterior chamber anatomy were established. Both cyclopentolate and pilocarpine cause angle narrowing in the rat eye, by different mechanisms.

Purpose To describe a series of myopic patients in whom a LASIK flap was created with the IntraLase femtosecond laser. The LADARVision (Alcon Laboratories Inc) tracking system failed and resulted in postponement of surgery. Methods Five myopic Asian patients with darkly pigmented irides underwent bilateral superior hinge flap creation with three different femtosecond laser (IntraLase Corp) pulse frequencies: 15, 30, and 60 kHz. Mean patient age, preoperative best spectacle-corrected visual acuity (BSCVA), and spherical equivalent refraction were 33 years, 20/20, and −6.25 diopters (D), respectively. Despite uncomplicated flap-lift and adequate pharmacologic dilated pupil diameter >7 mm, difficulty was experienced with LADAR-Vision eye tracking in 9 of 10 eyes. Intraoperative manipulations (fluid application, levitation of the laser bed, and tracking through a repositioned flap) were attempted to facilitate eye tracking at the time of femtosecond laser flap creation, but without success. Results The flap was repositioned, and patients were asked to return 1 to 5 days later, at which time the flap was relifted, eye tracking was successfully achieved, and the surgery was completed. Mean postoperative uncorrected visual acuity was 20/18 and no eyes lost any lines of BSCVA at 1 year. Conclusions Irregularities of the IntraLASIK stromal bed surface induce forward light scatter, and dark ocular pigmentation further reduces retinal reflectance, leading to tracking failure with the Alcon LADARVision platform. Delaying the surgery by 1 to 5 days may aid in reducing the light scatter, so that eye tracking can be achieved. [J Refract Surg. 2008;24:953–956.]

BackgroundHamad Medical Corporation (HMC) has been utilising the Occurrence, Variance, and Accident (OVA) reporting system to monitor, investigate, and improve potential or occurred adverse events. Pre-hospital emergency care is time-critical, and reporting OVAs is essential whilst ensuring ambulance availability for access to effective out-of-hospital care. This project aimed to reduce the average time consumed in incident reporting using the OVA system by HMC Ambulance Service (HMCAS) personnel from six minutes on 13 September 2022 to three minutes on 08 October 2022.MethodsA new incident reporting access icon with items customised to HMCAS operational needs was developed and integrated into the OVA reporting system. A sample of 483 OVAs (168 baselines; 315 following the streamlined process) reported to the HMCAS quality and patient safety department between 13 September and 08 October 2022 was considered. The time elapsed to fill an OVA was recorded. A sample of 22 OVAs before and after the intervention was used to create Shewhart’s t-chart, which assessed the impact of the HMCAS-specified incident reporting icon created in the OVA system on reducing the reporting time. Student t-tests for paired groups and bivariate regression analyses were conducted to evaluate the impact of the ‘Lean’ reporting process.1ResultsThe mean time of reporting an OVA dropped from 328.90 to 145.09 seconds. In table 1, the p-values <0.05 indicate a significant impact of the implemented intervention on the OVA reporting process. The Shewhart’s t-chart visually demonstrated the impact of the ‘Lean’ reporting process with fewer data points (figure 1).ConclusionsImplementing the new icon helped identify the new intervention’s significant impact on reducing time wasted reporting an OVA. This converges with the Lean principle by optimising internal procedures to reduce time wasted during incident reporting. It also helped ensure ambulances’ availability to respond to pre-hospital emergency calls.2Abstract 72 Figure 1Reduction in time spent completing OVA since the introduction of the new HMCASG RL-Datix icon and form[Figure omitted. See PDF]Abstract 72 Table 1Student-t-test for paired groups and bivariate regression analysest-Test: Paired Two Sample for Means Pre-intervention observations samplePost-intervention observations sampleP(T<=t) two-tailObservations 11 11 0.003 Mean 328.909 145.109 Variance 26041.091 16774.651 df 10 Bivariate Regression analysis Coefficients R Square Adjusted R Square p-value Lower 95% Upper 95% Time to complete OVAs 247.597 0.202 0.114 0.007 87.705 407.488 ReferencesDeming WE. Out of the crisis. MIT Press 2018;450.Akmal A, Greatbanks R, Foote J. Lean thinking in healthcare – findings from a systematic literature network and bibliometric analysis. Health Policy [Internet] 2020 Jun 1[Accessed 2023 Jan 8];124(6):615–27. Available from: https://www.sciencedirect.com/science/article/pii/S0168851020300932Ethical Approval/IRB StatementThis project was approved by the Hamad Medical Corporation Ambulance Service, Doha, Qatar, as a Quality Improvement project on 15/03/2022.Disclosures and AcknowledgmentsWe want to thank all of the Hamad Medical Corporation Corporate Quality and Patient Safety Department for their support of this project.

ABSTRACTPURPOSE: To report the history and clinical presentation of a 23year-old man who developed delayed onset lamellar keratitis in his right eye 2 weeks after uneventful LASIK for correction of myopia.METHODS: Initial clinical presentation suggested an infectious etiology, which led to therapeutic elevation of the LASIK flap and further microbiologic investigation with bacterial cultures.RESULTS: Bacterial cultures revealed Bacillus megateri urn, which was sensitive to all antibiotics against which it was tested. Twenty-four hours after initiating aggressive topical and oral antibiotic therapy, symptomatic relief occurred in the affected eye. The patient's uncorrected final visual acuity at 1-year follow-up was 20/15 in the right eye, and the stromal bed developed a faint peripheral non-visually significant scar.CONCLUSIONS: This case is an unusual presentation and course for microbial keratitis following LASIK, which occurred despite aseptic technique and fluoroquinolone antibiotic prophylaxis. Following refractive surgery one should be prepared to culture the lamellar interface in cases of suspected microbial keratitis and begin aggressive antibiotic therapy. [J Refract Surg. 2006;22:309312.]

Recently, researchers have investigated the capabilities of Large Language Models (LLMs) for generative recommender systems. Existing LLM-based recommender models are trained by adding user and item IDs to a discrete prompt template. However, the disconnect between IDs and natural language makes it difficult for the LLM to learn the relationship between users. To address this issue, we propose a PErsonAlized PrOmpt Distillation (PeaPOD) approach, to distill user preferences as personalized soft prompts. Considering the complexities of user preferences in the real world, we maintain a shared set of learnable prompts that are dynamically weighted based on the user's interests to construct the user-personalized prompt in a compositional manner. Experimental results on three real-world datasets demonstrate the effectiveness of our PeaPOD model on sequential recommendation, top-n recommendation, and explanation generation tasks.

Recent state-of-the-art recommender systems predominantly rely on either implicit or explicit feedback from users to suggest new items. While effective in recommending novel options, many recommender systems often use uninterpretable embeddings to represent user preferences. This lack of transparency not only limits user understanding of why certain items are suggested but also reduces the user's ability to scrutinize and modify their preferences, thereby affecting their ability to receive a list of preferred recommendations. Given the recent advances in Large Language Models (LLMs), we investigate how a properly crafted prompt can be used to summarize a user's preferences from past reviews and recommend items based only on language-based preferences. In particular, we study how LLMs can be prompted to generate a natural language (NL) user profile that holistically describe a user's preferences. These NL profiles can then be leveraged to fine-tune a LLM using only NL profiles to make transparent and scrutable recommendations. Furthermore, we validate the scrutability of our user profile-based recommender by investigating the impact on recommendation changes after editing NL user profiles. According to our evaluations of the model's rating prediction performance on two benchmarking rating prediction datasets, we observe that this novel approach maintains a performance level on par with established recommender systems in a warm-start setting. With a systematic analysis into the effect of updating user profiles and system prompts, we show the advantage of our approach in easier adjustment of user preferences and a greater autonomy over users' received recommendations.

In collaborative tasks, effective communication is crucial for achieving joint goals. One such task is collaborative building where builders must communicate with each other to construct desired structures in a simulated environment such as Minecraft. We aim to develop an intelligent builder agent to build structures based on user input through dialogue. However, in collaborative building, builders may encounter situations that are difficult to interpret based on the available information and instructions, leading to ambiguity. In the NeurIPS 2022 Competition NLP Task, we address two key research questions, with the goal of filling this gap: when should the agent ask for clarification, and what clarification questions should it ask? We move towards this target with two sub-tasks, a classification task and a ranking task. For the classification task, the goal is to determine whether the agent should ask for clarification based on the current world state and dialogue history. For the ranking task, the goal is to rank the relevant clarification questions from a pool of candidates. In this report, we briefly introduce our methods for the classification and ranking task. For the classification task, our model achieves an F1 score of 0.757, which placed the 3rd on the leaderboard. For the ranking task, our model achieves about 0.38 for Mean Reciprocal Rank by extending the traditional ranking model. Lastly, we discuss various neural approaches for the ranking task and future direction.