ASSESSMENT OF SIMULATED SURGICAL DEXTERITY AFTER MODIFIABLE EXTERNAL EXPOSURES AMONG NOVICE VERSUS EXPERIENCED VITREORETINAL SURGEONS.

PURPOSE: To evaluate novice and senior vitreoretinal surgeons after various exposures. Multiple comparisons ranked the importance of these exposures for surgical dexterity based on experience. METHODS: This prospective cohort study included 15 novice and 11 senior vitreoretinal surgeons (<2 and >10 years' practice, respectively). Eyesi-simulator tasks were performed after each exposure. Day 1, placebo, 2.5 mg/kg caffeine, and 5.0 mg/kg caffeine; day 2, placebo, 0.2 mg/kg propranolol, and 0.6 mg/kg propranolol; day 3, baseline simulation, breathalyzer readings of 0.06% to 0.10% and 0.11% to 0.15% blood alcohol concentrations; day 4, baseline simulation, push-up sets with 50% and 85% repetitions maximum; and day 5, 3-hour sleep deprivation. Eyesi-generated score (0-700, worst-best), out-of-tolerance tremor (0-100, best-worst), task completion time (minutes), and intraocular pathway (in millimeters) were measured. RESULTS: Novice surgeons performed worse after caffeine (-29.53, 95% confidence interval [CI]: -57.80 to -1.27, P = 0.041) and alcohol (-51.33, 95% CI: -80.49 to -22.16, P = 0.001) consumption. Alcohol caused longer intraocular instrument movement pathways (212.84 mm, 95% CI: 34.03-391.65 mm, P = 0.02) and greater tremor (7.72, 95% CI: 0.74-14.70, P = 0.003) among novices. Sleep deprivation negatively affected novice performance time (2.57 minutes, 95% CI: 1.09-4.05 minutes, P = 0.001) and tremor (8.62, 95% CI: 0.80-16.45, P = 0.03); however, their speed increased after propranolol (-1.43 minutes, 95% CI: -2.71 to -0.15 minutes, P = 0.029). Senior surgeons' scores deteriorated only following alcohol consumption (-47.36, 95% CI: -80.37 to -14.36, P = 0.005). CONCLUSION: Alcohol compromised all participants despite their expertise level. Experience negated the effects of caffeine, propranolol, exercise, and sleep deprivation on surgical skills.

A Polysomnographic Study of Effects of Sleep Deprivation on Novice and Senior Surgeons during Simulated Vitreoretinal Surgery.

PURPOSE: To assess the impact of a 3-hour polysomnography (PSG)-recorded night of sleep deprivation on next-morning simulated microsurgical skills among vitreoretinal (VR) surgeons with different levels of surgical experience and associate the sleep parameters obtained by PSG with Eyesi-generated performance. DESIGN: Self-controlled cohort study. PARTICIPANTS: Eleven junior VR surgery fellows with < 2 years of surgical experience and 11 senior surgeons with > 10 years of surgical practice. METHODS: Surgical performance was assessed at 7am after a 3-hour sleep-deprived night using the Eyesi simulator and compared with each subject's baseline performance. MAIN OUTCOME MEASURES: Changes in Eyesi-generated score (0-700, worst to best), time for task completion (minutes), tremor-specific score (0-100, worst to best), and out-of-tolerance tremor percentage. Polysomnography was recorded during sleep deprivation. RESULTS: Novice surgeons had worse simulated surgical performance after sleep deprivation compared with self-controlled baseline dexterity in the total score (559.1 ± 39.3 vs. 593.8 ± 31.7; P = 0.041), time for task completion (13.59 ± 3.87 minutes vs. 10.96 ± 1.95 minutes; P = 0.027), tremor-specific score (53.8 ± 19.7 vs. 70.0 ± 15.3; P = 0.031), and out-of-tolerance tremor (37.7% ± 11.9% vs. 28.0% ± 9.2%; P = 0.031), whereas no performance differences were detected in those parameters among the senior surgeons before and after sleep deprivation (P ≥ 0.05). Time for task completion increased by 26% (P = 0.048) in the post-sleep deprivation simulation sessions for all participants with a high apnea-hypopnea index (AHI) and by 37% (P = 0.008) among surgeons with fragmented sleep compared with those with normal AHI and < 10 arousals per hour, respectively. Fragmented sleep was the only polysomnographic parameter associated with a worse Eyesi-generated score, with a 10% (P = 0.005) decrease the following morning. CONCLUSIONS: This study detected impaired simulated surgical dexterity among novice surgeons after acute sleep deprivation, whereas senior surgeons maintained their surgical performance, suggesting that the impact of poor sleep quality on surgical skills is offset by increased experience. When considering the 2 study groups together, sleep fragmentation and AHI were associated with jeopardized surgical performance after sleep deprivation. FINANCIAL DISCLOSURE(S): The authors have no proprietary or commercial interest in any materials discussed in this article.

Real-life outcomes of subthreshold laser therapy for diabetic macular edema.

BACKGROUND: Diabetic macular edema (DME) is a major cause of visual impairment and its treatment is a public health challenge. Even though anti-angiogenic drugs are the gold-standard treatment, they are not ideal and subthreshold laser (SL) remains a viable and promising therapy in selected cases. The aim of this study was to evaluate its efficacy in a real-life setting. METHODS: Retrospective case series of 56 eyes of 36 patients with center-involving DME treated with SL monotherapy. Treatment was performed in a single session with the EasyRet® photocoagulator with the following parameters: 5% duty cycle, 200-ms pulse duration, 160-µm spot size and 50% power of the barely visible threshold. A high-density pattern was then applied to the whole edematous area, using multispot mode. Best corrected visual acuity (BCVA) and optical coherence tomography (OCT) data were obtained at baseline and around 3 months after treatment. RESULTS: Fifty-six eyes of 36 patients were included (39% women, mean age 64.8 years old); mean time between treatment day and follow-up visit was 14 ± 6 weeks. BCVA (Snellen converted to logMAR) was 0.59 ± 0.32 and 0.43 ± 0.25 at baseline and follow-up, respectively (p = 0.002). Thirty-two percent had prior panretinal photocoagulation (p = 0.011). Mean laser power was 555 ± 150 mW and number of spots was 1,109 ± 580. Intraretinal and subretinal fluid (SRF) was seen in 96 and 41% of eyes at baseline and improved in 35 and 74% of those after treatment, respectively. Quantitative analysis of central macular thickness (CMT) change was performed in a subset of 23 eyes, 43% of which exhibited > 10% CMT reduction post-treatment. CONCLUSIONS: Subthreshold laser therapy is known to have RPE function as its main target, modulating the activation of heat-shock proteins and normalizing cytokine expression. In the present study, the DME cases associated with SRF had the best anatomical response, while intraretinal edema responded poorly to laser monotherapy. BCVA and macular thickness exhibited a mild response, suggesting the need for combined treatment in most patients. Given the effect on SRF reabsorption, subthreshold laser therapy could be a viable treatment option in selected cases.

Comparison of 577-nm Multispot and Standard Single-Spot Photocoagulation for Diabetic Retinopathy.

OBJECTIVE: To compare two different laser strategies of panretinal photocoagulation for diabetic retinopathy. METHODS: Single-center, randomized study including 41 eyes treated with 577-nm multispot laser with a 20-ms pulse duration (group 1) or a 532-nm single-spot laser with a 100-ms pulse duration (group 2). The outcomes included best-corrected visual acuity (BCVA) and imaging changes at baseline, 6 and 12 months, laser parameters, and results of subjective pain analysis. RESULTS: At 12 months, the treatments did not differ significantly in BCVA, central retinal thicknesses (CRTs), improved macular edema, vitreomacular interface changes, patient-reported pain scores, or angiographic responses. Group 1 had significantly fewer treatment sessions but used more laser spots (p < 0.001). CONCLUSION: The multispot laser required fewer applications with more spots delivered to compensate for lower fluency, showing similar patient tolerance to single-spot laser. Both groups maintained the initial visual acuities and CRTs; about 50% of cases had vitreomacular interface changes and improved macular edema, with similar angiographic improvements after 12 months.

The use of multiple tools for teaching medical biochemistry.

In this work, we describe the use of several strategies employing the philosophies of active learning and problem-based learning (PBL) that may be used to improve the teaching of metabolic biochemistry to medical and nutritional undergraduate students. The main activities are as follows: 1) a seminar/poster system in a mini-congress format (using topics of applied biochemistry); 2) a true/false applied biochemistry exam (written by peer tutors); 3) a 9-h exam on metabolism (based in real publications); 4) the Advanced Biochemistry course (directed to peer tutors, where students learn how to read and criticize real medical papers); 5) experiments about nutrition and metabolism, using students as volunteers, and about free radicals (real science for students); 6) the BioBio blog (taking advantage of the "web age," this enhances out of class exchanges of information between the professor, students, and peer tutors); 7) student lectures on public health issues and metabolic disorders directed to the community and lay people; and 8) the BioBio quiz show. The main objective of these activities is to provide students with a more practical and interesting approach to biochemistry, such as the application of theoretical knowledge to real situations (diseases, experiments, media information, and scientific discoveries). In addition, we emphasize the importance of peer tutor activities for optimized learning of both students and peer tutors, the importance of a closer interaction between students and teaching staff, and the necessity to initiate students precociously in two broad fields of medical activity: "real" basic science and contact with the public (also helping students--future doctors and nutritionists--to be able to communicate with lay people). Most activities were evaluated by the students through written questionnaires and informal conversations, along various semesters, indicating good acceptance and approval of these methods. Good student scores in the biochemistry exams and seminars indicated that these activities are also working as valid educational tools.

Pizza and pasta help students learn metabolism.

In this article, we report on an experiment designed to improve the learning of metabolic biochemistry by nutrition and medical undergraduate students. Twelve students participated in a monitored lunch and had their blood extracted for analysis 1) before lunch, 2) 30 min after lunch, and 3) 3 h after lunch. The subjects were divided in two groups. One group had a hyperglicidic meal [pasta plus orange juice: 80% carbohydrate, 10% protein, and 10% lipid (estimated values)] and the other group had a hyperlipidic meal (calabresi pizza plus diet soda: 36% carbohydrate, 18% protein, and 46% lipid). Individual quantities of food were based on body mass index, age, and sex. The blood parameters analyzed were glucose, triglycerides (TG), and urea. Glucose remained constant in the three measurements in both groups. The TG concentration in the pasta group was constant before and after lunch but increased significantly during the evening. In the pizza group, TG increased after lunch and remained constant in the evening. Levels of urea increased only in the evening, specially in the pizza group. These results were used for the final biochemistry exam. With the maximum score set as 10, the average score was 6.0 +/- 2.4 (n = 102). We considered this activity a unique way of evaluating important issues on metabolism, because students had several hours to work on the final exam (with free access to a bibliography). It was also a good didactic experience (problem-based learning like) for the subject students, because they had to work in all phases of the experiment (idealization, realization, and analysis) and participated actively in the elaboration and correction of the exam.