Objective demonstration of eyelid spasm relief with smartphone and custom software in hemifacial spasm patients.

PURPOSE: To objectively demonstrate eyelid spasms relief in hemifacial spasm (HFS) patients using a smartphone and a custom-made software. METHODS: Nineteen patients with HFS had standardized videos recorded with a smartphone (iPhone 6S, Apple) camera before and 15 days after receiving onabotulinumtoxinA injections. Nineteen age-matched control subjects were also assessed. The Eye Aspect Ratio (EAR) is an algorithm previously described to determine whether the eye is opened or closed. When the eye is closed, EAR tends to be closer to zero. Analogously, if the eye is wide open, values are greater. A custom-made software using the EAR concept was developed and pre- and post-treatment EARs were analyzed to assess HFS patients. RESULTS: Botulinum toxin (BoNT) injections led to a significant increase in the average EAR of the affected side: + 10.4% (p = 0.0175) of HFS patients, compared to baseline. Mean EAR before BoNT applications were significantly lower (16.2%) on the affected side (0.25 ± 0.05) of HFS patients when compared to controls (0.30 ± 0.05, p = 0.004). After BoNT injections, no statistically significant difference was observed for the average EAR between the affected side of HFS patients (0.27 ± 0.04) and controls (p = 0.20). CONCLUSIONS: Use of a smartphone and custom-made software objectively demonstrated eyelid spasm relief in patients with HFS. Additional refinement of this system could permit more accurate assessments of treatment response rates for each patient, making it possible to be used in clinical practice.

Corneal Response to Scleral Contact Lens Wear in Keratoconus.

OBJECTIVE: To verify corneal alterations in patients with keratoconus who wear scleral contact lenses (ScCLs), focusing on corneal endothelial assessment. METHODS: Scleral contact lenses were fitted in 22 patients with keratoconus. During a 90-day follow-up, patients were assessed in three visits: at baseline, after 30 days, and after 90 days. Patients underwent visual acuity measurement, slitlamp biomicroscopy of the anterior segment, specular microscopy of the corneal endothelium, corneal pachymetry, measurement of the clearance between the cornea and the lens, and follow-up of ectasia. RESULTS: Variables related to endothelial morphology and pachymetry values did not change significantly over time. Central clearance measurements decreased in the 90-day period. No progression of corneal ectasia was observed, neither were infectious or inflammatory processes in the same period. CONCLUSION: Daily wear of ScCLs in patients with keratoconus was not associated with adverse effects on the cornea or endothelium over a period of 90 days nor was there evidence of disease progression. Central clearance values diminished over that period, but the significance of this observation remains unclear.

New Direct and Indirect Ophthalmoscopy Teaching Methodology for Veterinary Doctors.

Ophthalmic diseases can reflect the presence of systemic disease in animals. Thus, specialists in veterinary medicine must master the technique of fundus examination. To aid in the acquisition of this skill, we developed a teaching methodology using a low-cost model that students can build themselves and a device that allow for the examination of the animal's retina to teach the techniques of direct and indirect ophthalmoscopy in veterinary medicine.

Combining experiences of race gaming and natural driving affects gaze location strategy in simulated context.

The aims of the study were to investigate the effects of race gaming experience in playing racing video games on gaze behaviour and performance of drivers and the effects of natural driving experience on gaze behaviour and performance of gamers. Thirty participants, divided into drivers-gamers, drivers-non-gamers and non-drivers-gamers, were asked to drive in a race circuit as fast as possible while their eye movements were recorded. Drivers-gamers spent more time looking at the lane than non-drivers-gamers. Furthermore, drivers-gamers performed greater number of fixations towards the speedometer and showed faster performance in the racing task than the drivers-non-gamers. Combining natural driving and race gaming experiences changed the gaze location strategy of drivers. Practitioner summary: Racing video games practitioners have high propensity to exhibit attitudes and intentions of risky driving behaviour. Combining natural driving and race gaming experiences affects gaze behaviour strategy of drivers. Abbreviations: DG: Drivers-gamers; DNG: Drivers-non-gamers; NDG: Non-drivers-gamers; AOIs: Areas of Interest; r-NUMFIX: Relative number of fixations; r-DURFIX: Relative fixations duration.

Nova Metodologia de Ensino de Oftalmoscopia Direta e Indireta para Médicos.

As doenças oftalmológicas podem refletir a presença de doenças sistêmicas em animais. Assim, os especialistas em medicina veterinária devem dominar a técnica do exame de fundoscopia. Para auxiliar na aquisição dessa habilidade, desenvolvemos uma metodologia de ensino utilizando um modelo de baixo custo que permite o exame da retina para ensinar as técnicas de oftalmoscopia direta e indireta em medicina veterinária.

INTRAOCULAR PRESSURE CHANGES DURING VITRECTOMY USING CONSTELLATION VISION SYSTEM'S INTRAOCULAR PRESSURE CONTROL FEATURE.

PURPOSE: To evaluate intraocular pressure (IOP) changes during experimental vitrectomy and the efficacy of Constellation Vision System's IOP control (IOPc) feature in reestablishing baseline pressure. METHODS: Using a pressure transducer in freshly enucleated porcine eyes, a broad range of parameters (baseline pressures, aspiration levels, and cut rates) were tested with 23- and 25-gauge probes and IOPc turned ON versus OFF. RESULTS: IOPc turned ON was significantly more effective than IOPc turned OFF in controlling IOP drop and stabilizing pressure during vitrectomy using a wide range of baseline pressures (20-70 mmHg). The 23-gauge system consistently presented a reduced drop from baseline compared with the 25-gauge system. The overall average drop for the 23- and 25-gauge systems was 12.79 mmHg and 21.17 mmHg, respectively. Both gauge sizes reestablished baseline pressure approximately 1.6 seconds after the initial pressure drop generated at the beginning of aspiration. A peak of IOP (overshooting) was observed when the pressure was returning to baseline using both 23- and 25-gauge systems. CONCLUSION: Using IOPc feature turned ON, 23- and 25-gauge probes were effective in reestablishing and sustaining baseline infusion pressures, although 23-gauge probes showed less IOP fluctuation than did 25-gauge probes.

Ten-Year Follow-up of a Blind Patient Chronically Implanted with Epiretinal Prosthesis Argus I.

PURPOSE: The Argus I implant is the first-generation epiretinal prosthesis approved for an investigational clinical trial by the United States Food and Drug Administration. Herein we report testing results obtained from a 10-year follow-up to study the physiologic effects of the bioelectronic visual implant after prolonged chronic electrical stimulation. DESIGN: Case report. PARTICIPANT: One man, 55 years of age when enrolled in the study, underwent surgical implantation of the Argus I in June 2004, followed by periodic tests from July 2004 through June 2014, spanning a total of 10 years. METHODS: The decade-long follow-up consisted of implant system performance tests, subject visual function evaluation, and implant-retina interface analysis. MAIN OUTCOME MEASURES: Changes in electrode impedance and perceptual threshold over the time course; subject's performance on visual function task, orientation, and mobility tests; and optical coherence tomography data, fundus imaging, and fluorescein angiography results for the assessment of subject's implant-retina physical interface. RESULTS: Electrically elicited phosphenes were present 10 years after implantation of an epiretinal stimulator. The test subject not only was able to perceive phosphenes, but also could perform visual tasks at rates well above chance. CONCLUSIONS: This decade-long follow-up report provides further support for the use of retinal prostheses as a long-lasting treatment for some types of blindness.

Ultraviolet-A absorbance analysis in thin porcine corneas pre-and post-crosslinking.

PURPOSE: To determine the absorbance coefficient of the thin porcine cornea to ultraviolet-A radiation (365 nm) submitted for crosslinking. METHODS: This in vitro, benchtop experiment using cadaver tissue study analyzed 12 porcine corneal lamellas, which were obtained using a microkeratome after mechanical de-epithelization and separated into three thickness groups: 180, 300, and 360 µm. The corneal thickness values were measured by anterior-segment optical coherence tomography. All lamellas had ultraviolet-A (365 nm) absorbance measured with a 96-well plate spectrophotometer using an ultraviolet transparent microplate before riboflavin instillation and preand post-crosslinking according to the Dresden protocol. RESULTS: The ultraviolet absorbance profiles of the 180, 300, and 360 µm groups were obtained as α-coefficients of 12.85, 76.55, and 120.27, respectively. A theoretical formula was calculated though a statistical analysis that demonstrated the correlation between stromal lamellar thickness and ultraviolet absorbance. CONCLUSIONS: Corneal thickness and ultraviolet-A spectral absorbance of corneal lamellas showed linear correlation. These findings can potentially contribute to the optimization of ultraviolet-A application during crosslinking, making the treatment of corneas with thickness <400 µm safe and personalized energy delivery for each corneal thickness.

Comparative outcomes of mechanical and transepithelial PRK on the same excimer laser: A contralateral eye study.

PURPOSE: Compare refractive results between mechanical PRK (mPRK) and transepithelial PRK (tPRK) with WaveLight Allegretto EX500 excimer laser system (Alcon Laboratories, Fort Worth, TX, USA). SETTING: Department of Ophthalmology of the Federal University of Sao Paulo, Brazil. DESIGN: Prospective and randomized study. METHODS: In 151 eyes of 73 patients with astigmatism and myopia, both eyes had similar refraction before surgery, with a maximum of 15-µm difference in ablation who underwent mPRK in one eye and tPRK in the contralateral eye. The mean age of the patients in this study was 31.45 ± 6.97 years (range, 22 to 54 years). RESULTS: A comparison was made with all variables between the two groups, and we found that UDVA and SE were worse in the tPRK group at six months than in the mPRK group. In the mPRK group, there was a higher frequency in the +/- 0.50 range and a lower frequency in the +/- 1.50 range. In the tPRK group, however, there was a lower frequency in the +/- 0.50 range and a higher frequency in the +/- 1.50 range. Concerning gain or loss of lines of sight, there was no association between the two groups (chi-square test, p = 0.887). CONCLUSION: Both mPRK and tPRK appear to have similar safety. However, mPRK was associated with significantly better UDVA and SE six months post-operatively.

Variability of subjective classifications of corneal topography maps from LASIK candidates.

PURPOSE: To evaluate the variability of subjective corneal topography map classification between different experienced examiners and the impact of changing from an absolute to a normative scale on the classifications. METHODS: Preoperative axial curvature maps using Scheimpflug imaging obtained with the Pentacam HR (Oculus Optikgeräte, Wetzlar, Germany) and clinical parameters were sent to 11 corneal topography specialists for subjective classification according to the Ectasia Risk Scoring System. The study population included two groups: 11 eyes that developed ectasia after LASIK and 14 eyes that had successful and stable LASIK outcomes. Each case was first reviewed using the absolute scale masked to the patient group. After 3 months, the same cases were represented using a normative scale and reviewed again by the same examiners for new classifications masked to the patient group. RESULTS: Using the absolute scale, 17 of 25 (68%) cases had variations on the classifications from 0 to 4 for the same eye across examiners, and the overall agreement with the mode was 60%. Using the normative scale, the classifications from 11 of 25 (44%) cases varied from 0 to 4 for the same eye across examiners, and the overall agreement with the mode was 61%. Eight examiners (73%) reported statistically higher scores (P < .05) when using the normative scale. Considering all 550 topographic analyses (25 cases, 11 examiners, and two scales), the same classification from the two scales was reported for 121 case pairs (44%). CONCLUSION: There was significant inter-observer variability in the subjective classifications using the same scale, and significant intra-observer variability between scales. Changing from an absolute to a normative scale increased the scores on the classifications by the same examiner, but significant inter-observer variability in the subjective interpretation of the maps still persisted.

Use of artificial intelligence in ophthalmology: a narrative review.

BACKGROUND: Artificial intelligence (AI) deals with development of algorithms that seek to perceive one's environment and perform actions that maximize one's chance of successfully reaching one's predetermined goals. OBJECTIVE: To provide an overview of the basic principles of AI and its main studies in the fields of glaucoma, retinopathy of prematurity, age-related macular degeneration and diabetic retinopathy. From this perspective, the limitations and potential challenges that have accompanied the implementation and development of this new technology within ophthalmology are presented. DESIGN AND SETTING: Narrative review developed by a research group at the Universidade Federal de São Paulo (UNIFESP), São Paulo (SP), Brazil. METHODS: We searched the literature on the main applications of AI within ophthalmology, using the keywords "artificial intelligence", "diabetic retinopathy", "macular degeneration age-related", "glaucoma" and "retinopathy of prematurity," covering the period from January 1, 2007, to May 3, 2021. We used the MEDLINE database (via PubMed) and the LILACS database (via Virtual Health Library) to identify relevant articles. RESULTS: We retrieved 457 references, of which 47 were considered eligible for intensive review and critical analysis. CONCLUSION: Use of technology, as embodied in AI algorithms, is a way of providing an increasingly accurate service and enhancing scientific research. This forms a source of complement and innovation in relation to the daily skills of ophthalmologists. Thus, AI adds technology to human expertise.

Eye diseases during pregnancy: a study with the medical data warehouse in the eye clinic of the Ludwig-Maximilians-Universität München in Munich in Germany.

OBJECTIVE: To analyze the most common ophthalmologic disorders in pregnant women seen in a hospital in Munich in Germany using a big data analysis system, as well as to compare the results obtained with those from other epidemiological studies that used different data acquisition methods. METHODS: We retrospectively analyzed electronic health records of pregnant women who were seen at the ophthalmology department from 2003 to 2019 at the Ludwig-Maximilians-Universität München hospital. The main complaints that led to ophthalmic consultations during this period were evaluated, and also the variation in intraocular pressure of patients throughout gestational trimesters by analyzing data from the data warehouse system. RESULTS: A total of 27,326 electronic health records were analyzed. Of participants, 149 (0.54%) required eye care during pregnancy. Their mean intraocular pressure was 17mmHg in the first trimester, 12mmHg in the second trimester, and 14mmHg in the third trimester. The most prevalent findings were dry eye (29.3%) and conjunctivitis (16%), and ametropia (16%). The most common posterior segment problem was diabetic retinopathy (4.6%). The lower mean intraocular pressure in the second and third trimester found in our study is in accordance with other studies that used other method for data acquisition. CONCLUSION: The most common ophthalmic conditions found in this study population were dry eye, conjunctivitis, and ametropia. The use of data warehouse proved to be useful for acquiring and analyzing data from many patients. This study results are comparable with other studies in published literature that adopted different methodology.

Retinal microvascular density modifications during the water drinking test.

PURPOSE: The water drinking test (WDT) is a well-known stress test that increases intraocular pressure (IOP) momentarily and can indicate risk of glaucoma progression. This study focuses on correlating changes in the retinal microvascular plexus with the WDT in young healthy subjects. METHODS: A total of 20 eyes of 20 healthy young subjects (mean age 24.37 ± 2.17 years) were included in this study. In our protocol, WDT consisted of drinking 1 L of water within 5 min. Outcome measures in this prospective observational study were mean arterial pressure (MAP), heart rate (HR), IOP, and retinal vessel density of both superficial and deep macular retina using optical coherence tomography angiography (OCTA), which were assessed before water ingestion and four times after at 15-min intervals. OCTA images were later quantified by fractal analysis (box counting [Dbox]). One-way repeated measures analysis of variance (ANOVA) was used to assess the effects of WDT on each of the parameters. RESULTS: The WDT resulted in significant peak changes of the following parameters compared to baseline: IOP: 15.63 ± 3.37 versus 18.38 ± 4.53 mmHg at 30 min, p < 0.001; HR: 75.74 ± 12.23 versus 64.95 ± 11.37 bpm at 15 min, p < 0.001; deep retinal vessel density 1.758 ± 0.14 versus 1.749 ± 0.16 at 15 min, p = 0.040. CONCLUSIONS: Besides IOP elevation and systemic effects in HR, WDT is associated with temporary modifications of the deep vascular plexus in young healthy subjects.

Titanium Powder 3D-Printing Technology for a Novel Keratoprosthesis in Alkali-Burned Rabbits.

Purpose: To evaluate the surgical technique, clinical performance, and biocompatibility of a novel keratoprosthesis (KPro) named KPro of Brazil (KoBra) in an alkali-burned rabbit model. Methods: Two-piece three-dimensional-printed titanium powder and polymethyl methacrylate KPros were implanted into 14 alkali-burned corneas of 14 rabbits using an autologous full-thickness corneal graft as the KPro carrier. Rabbits were examined weekly for 12 months to evaluate retention and postoperative complications. Anterior segment optical coherence tomography (AS-OCT) and scanning electron microscopy (SEM) were performed at the end of the experiment to evaluate the relationship between the KoBra and the carrier graft. Results: All surgeries were performed without intraoperative complications, and the immediate postoperative period was uneventful. In 12 eyes (85.7%), the implanted KPros integrated into the operated eyes and maintained clear optics without extrusion or further complications over 12 months. Two eyes presented late postoperative complications that progressed to KPro extrusion: one had a presumed infectious keratitis, and the other had sterile stromal necrosis. AS-OCT demonstrated the correct relationship of the device and carrier graft in all remaining animals at the final follow-up. SEM findings indicate the integration of the porous structure of the back plate into the surrounding tissue. Conclusions: Clinical evaluations, AS-OCT, and SEM findings indicate good biointegr-ation of the implanted device into the corneal carrier graft. KoBra has the advantage of using recipients' own corneas as the prosthesis supporter, and its surgical procedure is relatively simple and safe. Translational Relevance: Titanium three-dimensional-printed technology used in an animal limbal stem-cell deficiency model holds great promise for the treatment of corneal blindness in humans.

In search of disambiguation: development of eye drop bottle sleeves to aid in identification and survey among possible users. A cross-sectional study.

BACKGROUND: Considerable numbers of individuals present low vision, blindness, illiteracy and other conditions that could possibly impair their identification of medications, such as eye drops. Through helping these individuals to identify their eye drops, they can achieve greater autonomy. Misidentification can be avoided through use of multisensory sleeves that can be adapted to most eye drop bottles. Correct use of eye drops is important for preventing progression of diseases like glaucoma that could potentially lead to blindness. OBJECTIVE: To develop bottle sleeves to aid in identification of eye drops and then interview a group of possible users to evaluate the acceptance of the solution. DESIGN AND SETTING: Cross-sectional survey performed at an ophthalmological clinic in São Paulo (SP), Brazil. METHODS: We describe the development of multisensory sleeves to assist in identification of eye drops. To assess the acceptance of this solution, we interviewed 18 patients who were currently using three or more types of eye drops. RESULTS: We developed four prototypes for eye drop bottle sleeves and conducted an acceptance test on them. Most of the patients who answered the survey about the sleeves were elderly. Most (95%) reported believing that the sleeves would help reduce the risk of mixing up eye drops with other medications that also dispense drops. They also believed that these would increase their autonomy in using eye drops. CONCLUSION: The solution presented was well accepted and may help increase safety in using eye drops through preventing misidentification.

Pain response and symptoms in photorefractive keratectomy: mechanical de-epithelization compared with transepithelial ablation.

PURPOSE: To compare postoperative pain and discomfort between mechanical and transepithelial photorefractive keratectomies. METHODS: This prospective comparative study included 190 eyes of 95 patients with hyperopia (up to +4.00 D), astigmatism (up to -5.00 D), and myopia (up to -8.00 D) who underwent mechanical photorefractive keratectomy in one eye and transepithelial photorefractive keratectomy in the contralateral eye using Wavelight Allegretto EX500 excimer laser. The patients were unaware of the side treated with each technique. The interval between operations in the same patient was 15-30 days. Both eyes had similar refraction before surgery, with a maximum of 15-µm difference in ablation. Postoperative questionnaires were administered on days 1 and 7 to assess the patients' level of discomfort (0=no discomfort to 5=extreme discomfort) with the following symptoms: pain, burning sensation, itchiness, tearing, photophobia, eye redness, foreign body sensation, and eyelid swelling. Patients were also asked about which method they preferred. RESULTS: The sample consisted of 61 women (64.21%) and 34 men (35.79%). The mean (SD) patient age was 31.66 (6.69) years (range, 22-54 years). On postoperative day 1, the patients reported significantly less discomfort in terms of pain (1.9 ± 1.74 vs 2.5 ± 1.83; p=0.017), burning sensation (1.8 ± 1.56 vs 2.5 ± 1.68; p=0.004), tearing (2.3 ± 1.71 vs 3.1 ± 1.69; p=0.001), and foreign body sensation (1.9 ± 1.77 vs 2.5 ± 1.86; p=0.024) in the eye that received mechanical photorefractive keratectomy than in the eye that received transepithelial photorefractive keratectomy. No significant differences were found between the mechanical and transepithelial photorefractive keratectomies on postoperative day 7. Fifty-nine patients (62.10%) preferred mechanical photorefractive keratectomy, while 32 (33.68%) preferred transepithelial photorefractive keratectomy. Four patients (4.22%) expressed no preference. CONCLUSIONS: Our results showed that pain scores were significantly lower in the mechanical photorefractive keratectomy-treated eyes than in the transepithelial photorefractive keratectomy-treated eyes on postoperative day 1, which may have provided greater patient comfort after surgery and led patients to prefer the mechanical photorefractive keratectomy technique.

COVID 19 repercussions in ophthalmology: a narrative review.

BACKGROUND: The new coronavirus of 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread globally and has repercussions within ophthalmological care. It has caused ocular manifestations in some patients, which can spread through eye secretions. OBJECTIVES: The purpose of this review was to summarize the currently available evidence on COVID-19 with regard to its implications for ophthalmology. DESIGN AND SETTING: Narrative review developed by a research group at Universidade Federal de São Paulo (UNIFESP), São Paulo (SP), Brazil, and at Ludwig-Maximilians-Universität, Munich, Germany. METHODS: We searched the literature on the repercussions of COVID-19 within ophthalmological care, using the MEDLINE and LILACS databases, with the keywords "COVID-19", "ophthalmology" and "coronavirus", from January 1, 2020, to March 27, 2021. Clinical trials, meta-analysis, randomized controlled trials, reviews and systematic reviews were identified. RESULTS: We retrieved 884 references, of which 42 were considered eligible for intensive review and critical analysis. Most of the studies selected reported the evidence regarding COVID-19 and its implications for ophthalmology. CONCLUSIONS: Knowledge of eye symptoms and ocular transmission of the virus remains incomplete. New clinical trials with larger numbers of patients may answer these questions in the future. Moreover, positively, implementation of innovative changes in medicine such as telemedicine and artificial intelligence may assist in diagnosing eye diseases and in training and education for students.