The Inflammatory and Cytological Effect of Repeated Povidone-Iodine Application in Patients Receiving Intravitreal Injections.

OBJECTIVE: To investigate the effect of repeated povidone-iodine (PVI) application on the ocular surface parameters of patients who received intravitreal injections. MATERIALS AND METHODS: In this prospective study, 52 eyes of 52 patients with age-related macular degeneration who underwent unilateral intravitreal injection at least three times in the last 1 year (intravitreal injection [IVI] group), 52 fellow eyes with no previous intravitreal injection (NIVI group), and 51 eyes of 51 healthy subjects (control) were included. Tear break-up time (TBUT), the Schirmer test, the Oxford staining score, the Ocular Surface Disease Index questionnaire, conjunctival impression cytology, and tear inflammatory cytokine levels (interleukin [IL]-1ß and IL-6) were analyzed in all participants. RESULTS: The IVI group had lower TBUT and higher Oxford staining score than the NIVI and control groups ( P <0.05). No significant difference was found between the groups in the Schirmer test ( P =0.161). Conjunctival impression cytology analysis revealed that the IVI group had a significantly lower goblet cell count and significantly higher Nelson staging result than the NIVI and control groups ( P <0.05). As a result of tear cytokine analysis, although IVI and NIVI groups had higher IL-1ß and IL-6 levels than the control group ( P <0.05), there was no difference between NIVI and IVI groups ( P ≥0.05). CONCLUSIONS: Repeated PVI application caused cytotoxic injury to the ocular surface, resulting in goblet cell loss and squamous metaplasia of epithelial cells. As a result, the stability of the tear film layer was found to be impaired and ocular surface-related symptoms developed in patients.

Characteristics of myopic and hyperopic eyes in patients with antimetropia.

CLINICAL RELEVANCE: Antimetropia is a rare type of anisometropia in which one eye is myopic and the fellow is hyperopic, This optical condition condition permits the evaluation of both sides of the emmetropisation process failure in the same individual by minimising genetic and environmental factors. BACKGROUND: This study aimed to evaluate the ocular biometric, retinal, and choroidal characteristics of myopic and hyperopic eyes of antimetropic subjects older than six years. METHODS: In this retrospective study, myopic and hyperopic eyes of 29 antimetropic patients with a spherical equivalent (SE) difference of at least 2.00D between the eyes were included. Axial length (AL), mean corneal keratometry, anterior chamber depth, the proportion of anterior chamber depth in AL, crystalline lens power, central macular thicknesses, disc-to-fovea distance, fovea-disc angle, peripapillary retinal nerve fibre layer (RNFL) thicknesses, and subfoveal choroidal features were compared between the eyes. The prevalence of amblyopia was determined. Refractive parameters and total astigmatic profile were evaluated in eyes with and without amblyopia. RESULTS: The median absolute SE and AL differences between the eyes were 3.50D (interquartile range:1.75) and 1.18 mm (interquartile range:0.76), respectively (p < 0.001). Myopic eyes had lower crystalline lens power and proportion of anterior chamber depth in AL, and longer disc-to-fovea distance. Macular thicknesses, global RNFL, and temporal RNFL were thicker in myopic eyes, and there was no difference in other RNFL quadrants. Despite the increase in the choroidal vascularity index, other choroidal parameters were decreased in myopic eyes. Amblyopia was found in three of the myopic eyes and seven of the hyperopic eyes (p = 0.343). The highest interocular SE and AL difference and the highest frequency of anisoastigmatism were observed in patients with amblyopia in the myopic eye. CONCLUSION: Each ocular structure may respond differently to, or may be affected differently by, ametropic conditions.

Detection and Classification of Diabetic Macular Edema with a Desktop-Based Code-Free Machine Learning Tool.

Objectives: To evaluate the effectiveness of the Lobe application, a machine learning (ML) tool that can be used on a personal computer without requiring coding expertise, in the recognition and classification of diabetic macular edema (DME) in spectral-domain optical coherence tomography (SD-OCT) scans. Materials and Methods: A total of 695 cross-sectional SD-OCT images from 336 patients with DME and 200 OCT images of 200 healthy controls were included. Images with DME were classified into three main types: diffuse retinal edema (DRE), cystoid macular edema (CME), and cystoid macular degeneration (CMD). To develop the ML model, we used the desktop-based code-free Lobe application, which includes a pre-trained ResNet-50 V2 convolutional neural network and is available free of charge. The performance of the trained model in recognizing and classifying DME was evaluated with 41 DRE, 28 CMD, 70 CME, and 40 normal SD-OCT images that were not used in the training. Results: The developed model showed 99.28% sensitivity and 100% specificity for class-independent detection of DME. Sensitivity and specificity by labels were 87.80% and 98.57% for DRE, 96.43% and 99.29% for CME, and 95.71% and 95.41% for CMD, respectively. Conclusion: To our knowledge, this is the first evaluation of the effectiveness of Lobe with ophthalmological images, and the results indicate that it can be used with high efficiency in the recognition and classification of DME from SD-OCT images by ophthalmologists without coding expertise.