Evaluation of the (Baha) technique of scleral indentation using a self-retained scleral indenter during vitrectomy surgery: a randomized trial.

AIMS: The current study compared a novel technique of scleral indentation using the self-retaining Leyla retractor to the conventional scleral self-indentation with the chandelier light. METHODS: Patients with rhegmatogenous retinal detachment were randomized on a 1:1 basis to either have the (Baha) indentation using a tip of a thimble scleral indenter welded to the support for the Leyla retractor system or to have the conventional scleral indentation while using a 25-gauge chandelier light. A video was recorded for the surgery of all the cases and reviewed by another consultant masked to the type of indentation. The indentation duration (i.e., the time in seconds between the first appearance of a hump due to scleral indentation in the recorded video until its final disappearance) was measured for every case. RESULTS: The current study included 60 eyes of 60 adults with a mean age of 59.6 ± 9.8 years. Thirty-nine of the eyes were phakic and 21 were pseudophakic. The mean indentation time was 618 ± 87 and 696 ± 72 s in (Baha) indentation and conventional indentation groups, respectively. The difference was not statistically significant (p = 38). There was a positive correlation between the vertical palpebral fissure height and the indentation duration for both (Baha) indentation (r = 0.58) and conventional indentation groups (r = 0.42). Readjustment of the chandelier endo-illumination was required in 19 cases (63.3%) in the conventional indentation group. Iatrogenic breaks or accidental crystalline lens touch did not occur in any case. CONCLUSION: The (Baha) technique is effective and safe, especially in patients with a larger palpebral fissure.

Development and international validation of custom-engineered and code-free deep-learning models for detection of plus disease in retinopathy of prematurity: a retrospective study.

BACKGROUND: Retinopathy of prematurity (ROP), a leading cause of childhood blindness, is diagnosed through interval screening by paediatric ophthalmologists. However, improved survival of premature neonates coupled with a scarcity of available experts has raised concerns about the sustainability of this approach. We aimed to develop bespoke and code-free deep learning-based classifiers for plus disease, a hallmark of ROP, in an ethnically diverse population in London, UK, and externally validate them in ethnically, geographically, and socioeconomically diverse populations in four countries and three continents. Code-free deep learning is not reliant on the availability of expertly trained data scientists, thus being of particular potential benefit for low resource health-care settings. METHODS: This retrospective cohort study used retinal images from 1370 neonates admitted to a neonatal unit at Homerton University Hospital NHS Foundation Trust, London, UK, between 2008 and 2018. Images were acquired using a Retcam Version 2 device (Natus Medical, Pleasanton, CA, USA) on all babies who were either born at less than 32 weeks gestational age or had a birthweight of less than 1501 g. Each images was graded by two junior ophthalmologists with disagreements adjudicated by a senior paediatric ophthalmologist. Bespoke and code-free deep learning models (CFDL) were developed for the discrimination of healthy, pre-plus disease, and plus disease. Performance was assessed internally on 200 images with the majority vote of three senior paediatric ophthalmologists as the reference standard. External validation was on 338 retinal images from four separate datasets from the USA, Brazil, and Egypt with images derived from Retcam and the 3nethra neo device (Forus Health, Bengaluru, India). FINDINGS: Of the 7414 retinal images in the original dataset, 6141 images were used in the final development dataset. For the discrimination of healthy versus pre-plus or plus disease, the bespoke model had an area under the curve (AUC) of 0·986 (95% CI 0·973-0·996) and the CFDL model had an AUC of 0·989 (0·979-0·997) on the internal test set. Both models generalised well to external validation test sets acquired using the Retcam for discriminating healthy from pre-plus or plus disease (bespoke range was 0·975-1·000 and CFDL range was 0·969-0·995). The CFDL model was inferior to the bespoke model on discriminating pre-plus disease from healthy or plus disease in the USA dataset (CFDL 0·808 [95% CI 0·671-0·909, bespoke 0·942 [0·892-0·982]], p=0·0070). Performance also reduced when tested on the 3nethra neo imaging device (CFDL 0·865 [0·742-0·965] and bespoke 0·891 [0·783-0·977]). INTERPRETATION: Both bespoke and CFDL models conferred similar performance to senior paediatric ophthalmologists for discriminating healthy retinal images from ones with features of pre-plus or plus disease; however, CFDL models might generalise less well when considering minority classes. Care should be taken when testing on data acquired using alternative imaging devices from that used for the development dataset. Our study justifies further validation of plus disease classifiers in ROP screening and supports a potential role for code-free approaches to help prevent blindness in vulnerable neonates. FUNDING: National Institute for Health Research Biomedical Research Centre based at Moorfields Eye Hospital NHS Foundation Trust and the University College London Institute of Ophthalmology. TRANSLATIONS: For the Portuguese and Arabic translations of the abstract see Supplementary Materials section.

Prevalence of diabetic retinopathy in patients with diabetes in Alexandria and North-West Delta, Egypt.

PURPOSE: The purpose of this research was to estimate the prevalence of DR in Alexandria and the North-West Delta region. METHODS: All diabetic patients attending the general ophthalmology clinics (Group 1), diabetic internal medicine clinics (Group 2), or reached out in the local communities (Group 3) were eligible to participate. Fundus photographs were graded according to the Scottish DR grading system by three independent UK-certified graders. Adjudication by a consultant was done when needed. RESULTS: Out of 11,033 screened patients, 10,811 had a gradable fundus photograph in at least one eye and were included. The numbers of cases in groups 1, 2 and 3 were 3940, 2826, and 4045, respectively. Males represented 38.35% of the cases. Mean age was 55 ± 12.63. For the whole sample, groups 1, 2 and 3, the DR prevalence was 32.49, 46.4%, 29.13%, and 21.29%, respectively. The prevalence of proliferative DR (grade R4) was 6.16%, 11.83%, 5.02%, and 1.45%, respectively, and of referable maculopathy (Grade M2) was 19.95%, 31.42%, 15.92%, and 11.59%, respectively. In univariate analysis, older age, higher random blood glucose, and longer DM duration were associated with a higher risk of both DR and referable diabetic maculopathy. This association was maintained in multivariate analysis for the high random blood glucose level and the longer duration of DM (but not for the older age). CONCLUSION: A significantly higher prevalence of DR, grades R4 and M2 was found in the hospital-recruited patients than in diabetics from the local communities.

The Postnatal Growth and Retinopathy of Prematurity Model: A Multi-institutional Validation Study.

PURPOSE: The G-ROP model was proposed to improve the retinopathy of prematurity (ROP) screening efficiency. It is based on gestational age, birth weight and postnatal weight gain. The current study aimed to validate the G-ROP model's ability to predict ROP in cohorts of premature infants from Egypt and the United Kingdom (UK). METHODS: We retrospectively reviewed the records of preterm infants born between 1st of January and 30th of June 2018 with a known outcome for ROP screening and regular weight measurements until day 39 after birth. We applied the G-ROP model to the study group and calculated the sensitivity of the model for detecting Early Treatment of ROP (ETROP) study type 1 ROP and for any ROP and calculated the reduction of the number of infants requiring ROP screening by the model application. RESULTS: We applied the G-ROP model on 605 infants (504 from Egypt and 101 from the UK). The model successfully predicted all type 1 ROP cases (100% sensitivity) in both cohorts (95% confidence interval [CI], 91.1-100% in the Egyptian cohort and 65.5-100% in the UK cohort). The model reduced the number of infants requiring screening by 14.1% in the Egyptian cohort and 21.8% in the UK cohort. CONCLUSIONS: The G-ROP model was successfully validated for detecting type 1 ROP and in both cohorts from Egypt and the UK.

Evaluation of the use of NGage® Nitinol stone extractor for intraocular foreign body removal.

PURPOSE: To describe a novel technique to use the NGage® Nitinol Stone Extractor for large IOFB extraction. METHODS: We conducted a retrospective case series study by reviewing the data of 4 eyes with retained large IOFB extracted with the use of the NGage® Nitinol Stone Extractor. The study was conducted in a single tertiary referral center on four eyes of four patients with large retained IOFB. Studied eyes were treated by pars plana vitrectomy (PPV) and IOFB extraction by using the NGage® Nitinol Stone Extractor through a limbal incision. RESULTS: Four eyes of four male patients with large Retained IOFB were included in the study. The nature of the IOFB was metallic in 2 eyes, glass in 1 eye or ceramic 1 eye. All the IOFB were removed from a limbal wound. Silicone oil tamponade was required in 3 eyes. Two eyes required reoperation. At 6 months postoperative, the final visual acuity using Snellen chart ranged between PL and 0.1. CONCLUSION: The NGage® Nitinol Stone Extractor can be a useful tool for the extraction of the large retained IOFB.

Trimanual vitrectomy for severe proliferative diabetic retinopathy.

PURPOSE: To describe and evaluate a novel technique of pars plana vitrectomy (PPV) under chandelier illumination which is aided with the vital dyes and perfluorocarbon liquids for the management of the complex diabetic vitrectomy cases. METHODS: We conducted a prospective interventional comparative study on 40 eyes of 36 patients with advanced diabetic eye disease requiring PPV. The study was conducted in a single tertiary referral center. Eyes were divided on 1:1 basis by stratified randomization into two groups. Group 1 had trimanual vitrectomy done assisted with chandelier illumination, perfluorocarbon liquid (PFCL) and vital dyes. Group 2 had the conventional bimanual vitrectomy done assisted with chandelier illumination only. All patients were followed up for a minimum of 6 months after the surgery. RESULTS: Forty eyes of 36 patients with the mean age of 51.42 years (range 28-69) were evaluated. The anatomical success at 6 months could be achieved in all the eyes in both groups. The complete removal of the pre-retinal proliferations could be accomplished in all the eyes in the trimanual PPV group, and only in 85% of the eyes in the bimanual PPV group. Operative time was significantly shorter in the trimanual PPV group (p < 0.001). More eyes in the trimanual PPV group (55.0%) could achieve better vision (> 6/60) 6 months after the operation compared to the bimanual PPV group (50.0%), but this difference was not statistically significant. CONCLUSION: Trimanual PPV is a novel, safe and effective technique that can improve the results of the complex diabetic PPV.