Retinopathy of prematurity in preterm infants born following assisted conception versus spontaneously conceived pregnancies – A 2-year retrospective observational study from an urban tertiary eye care referral center in South India

Purpose: The aim of this study is to determine if in vitro fertilization (IVF) is associated with an increase in the incidence of retinopathy of prematurity (ROP) among preterm infants. Methods: This retrospective, comparative study included all the preterm babies who were screened under an urban multicentric outreach project between April 2019 and August 2022. Infant details including gender, birth weight, mode of conception, single or multiple gestation, gestational age and post?menstrual age in weeks, age at presentation, and any presence of risk factors were recorded and analyzed. Results: Among 444 preterm babies included in the study, 373 (84%) were conceived normally and 71 (16%) were conceived by IVF. ROP was found in 99 (22.29%) babies in total. There was no significant difference in the incidence of any stage of ROP between the two groups; however, higher stages of ROP were found to be relatively more frequent in the spontaneous conception group in our study. We also found a statistically significant difference in the presence of ROP among singletons, twins, and triplets. Conclusion: IVF was found not to independently increase the risk of ROP in preterm infants. More prospective studies and randomized controlled trials are needed to establish the relationship between the mode of conception and development of severe ROP in preterm infants

Bilateral choroidal effusion following vaccination against SARS-CoV-2 virus

An 80-year-old systemically stable female presented with sudden blurring of vision post the first dose of Covishield™, a non-replicating viral vector vaccine. On examination, she was found to have bilateral serous choroidal effusions. A thorough systemic and ocular workup was performed to rule out other causes of choroidal effusion. The effusions resolved with tapering doses of oral and systemic steroids. To the best of our knowledge, at the time of submission, this is the first case of choroidal effusion being reported after the coronavirus disease 2019 (COVID-19) vaccine.

The use of handheld spectral domain optical coherence tomography in pediatric ophthalmology practice: Our experience of 975 infants and children.

Purpose: Optical coherence tomography (OCT) is an important imaging tool assessing retinal architecture. In this article, we report a single centers experience of using handheld spectral domain (SD)‑OCT in a pediatric population using the Envisu 2300 (Bioptigen Inc., Research Triangle Park, NC, USA). Methods: We studied SD‑OCT images from 975 patients imaged from January 2011 to December 2014. The variety of cases that underwent an SD‑OCT was analyzed. Cases examples from different case scenarios were selected to showcase unique examples of many diseases. Results: Three hundred and sixty‑eight infants (37.7%) were imaged for retinopathy of prematurity, 362 children (37.1%) underwent the test for evaluation of suboptimal vision or an unexplained vision loss, 126 children (12.9%) for evaluation of nystagmus or night blindness, 54 children (5.5%) for an intraocular tumor or a mass lesion such as retinoblastoma, and 65 children (6.7%) for other diseases of the pediatric retina. The unique findings in the retinal morphology seen with some of these diseases are discussed. Conclusion: The handheld SD‑OCT is useful in the evaluation of the pediatric retinal diseases. The test is useful in the assessment of vision development in premature children, evaluation of unexplained vision loss and amblyopia, nystagmus and night blindness, and intraocular tumors (including retinoblastoma).

Retinal Oximetry: The Indian Experience in Healthy and Diseased Eyes.

To study the alterations in retinal oxygen saturations in healthy and diseased eyes. Patients presenting to our hospital underwent an additional non-invasive procedure to measure oxygen saturation in their retinal vessels. After dilatation, oximetry was done using the Oxymap T1 retinal oximeter (Oxymap hf, Reykjavik, Iceland). Normal patients and patients with arteriolar and venous occlusions, retinal dystrophies and glaucoma, were evaluated. Arteriolar, venous and arteryvenous saturation difference (AVSD) values were determined for each of the groups. In the normal subjects (n = 98), the average arteriolar saturation was 90.3 ± 6.5, and the venous saturation was 56.9 ± 6.3. The average AVSD was 33.4 ± 5.0. In arterial occlusions (n = 10), we have seen an initial fall in arteriolar (85.8%) and venous (49.7%) saturations in the acute stage in eyes with central retinal artery occlusion with subsequent increase in saturations. In venous occlusions (n = 18), there was an initial increase in all global saturation parameters in the acute stage (arteriolar: 105.8%, venous: 62.7%, AVSD: 43.3%), followed by a gradual decrease in saturations in the chronic stage (arteriolar: 99.8%, venous: 60.1%, AVSD: 39.8%). Eyes with retinitis pigmentosa (n=62) showed higher saturations (104.15%) and higher AVSD (44.15%) compared to macular dystrophies (n = 23) (96.7% and 41.61%) and normal controls (90.6% and 33.3%). Macular dystrophies showed higher global arteriolar values and AVSD but comparable venous values to the control group. In glaucoma (n = 44), we have seen raised arteriolar and AVSD values. Oximetry is sensitive in picking up changes in diseased eyes that are distinct from normal values. In the future, it may prove to be useful in pre-clinical screening studies and in therapeutic decision making.

Axial length and cone density as assessed with adaptive optics in myopia.

Aim: To assess the variations in cone mosaic in myopia and its correlation with axial length (AL). Subjects and Methods: Twenty‑five healthy myopic volunteers underwent assessment of photoreceptors using adaptive optics retinal camera at 2° and 3° from the foveal center in four quadrants superior, inferior, temporal and nasal. Data was analyzed using SPSS version 17 (IBM). Multivariable regression analysis was conducted to study the relation between cone density and AL, quadrant around the fovea and eccentricity from the fovea. Results: The mean cone density was significantly lower as the eccentricity increased from 2° from the fovea to 3° (18,560 ± 5455–16,404 ± 4494/mm2 respectively). There was also a statistically significant difference between four quadrants around the fovea. The correlation of cone density and spacing with AL showed that there was a significant inverse relation of AL with the cone density. Conclusion: In myopic patients with good visual acuity cone density around the fovea depends on the quadrant, distance from the fovea as well as the AL. The strength of the relation of AL with cone density depends on the quadrant and distance.

Microscope‑integrated optical coherence tomography: A new surgical tool in vitreoretinal surgery.

Optical coherence tomography (OCT) has revolutionized imaging of ocular structures and various disease conditions. Though it has been used in the clinic for some decades, the OCT has only recently found its way into the operating theater. Early attempts at intraoperative OCT, hand‑held and microscope mounted, have already improved our understanding of the surgical pathology and the role it might play in surgical decision‑making. The microscope‑integrated OCT now allows seamless, high‑resolution, real‑time imaging of surgical maneuvers from the incision to wound closure. Visualization of instruments and intraoperative tissue manipulation are possible with this in vivo modality and, therefore, help improve the outcome of surgery. In this article, we describe the advantages it offers during various vitreoretinal procedures.

Differential systemic gene expression profile in patients with diabetic macular edema: Responders versus nonresponders to standard treatment.

Introduction: Diabetic macular edema (DME) is a vision-threatening complication of diabetic retinopathy. The current practice of management is a” trial and error “method of using intravitreal antivascular endothelial growth factor (VEGF)’’ or steroids to treat the patient and watch the response. However, if the patient’s genetic profi le helps us choose appropriate medicine, it would help customize treatment option for each patient. This forms the basis of our study. Materials and Methods: A case-control, prospective, observational series, where DME patients were treated with bevacizumab and subclassifi ed as treatment naïve, treatment responders, and treatment nonresponders. Blood samples of 20 subjects were studied, with fi ve patients in each of the groups (nondiabetic- group 1, treatment naïve- group 2, treatment responder- group 3, and treatment nonresponder-group 4). Whole blood RNA extraction followed by labeling, amplifi cation and hybridization was done, and microarray data analyzed. Genes were classifi ed based on functional category and pathways. Results: The total number of genes upregulated among all three experimental groups was 5, whereas 105 genes were downregulated. There were no common genes upregulated between the responders and nonresponders. There was only one gene upregulated between the diabetic and diabetic responders postt reatment. There were 19 genes upregulated and 8 genes downregulated in the infl ammatory pathway in group 2 versus group 1. There were no downregulated genes detected in vascular angiogenesis and transcription group. There were identical numbers of genes up- and downregulated in the infl ammatory pathway. Seventeen genes were upreguated and 11 genes downregulated in receptor activity, which remained the predominant group in the group classifi cation. Discussion: In summary, this study would provide an insight into the probable signaling mechanisms for disease pathogenesis as well as progression. This type of study eventually would aid in developing or improvising existing treatment modules with a rational approach towards personalized medicine, in future addressing the diff erential responses to treatment.

Adaptive optics imaging of the retina.

Adaptive optics is a relatively new tool that is available to ophthalmologists for study of cellular level details. In addition to the axial resolution provided by the spectral-domain optical coherence tomography, adaptive optics provides an excellent lateral resolution, enabling visualization of the photoreceptors, blood vessels and details of the optic nerve head. We att empt a mini review of the current role of adaptive optics in retinal imaging. PubMed search was performed with key words Adaptive optics OR Retina OR Retinal imaging. Conference abstracts were searched from the Association for Research in Vision and Ophthalmology (ARVO) and American Academy of Ophthalmology (AAO) meetings. In total, 261 relevant publications and 389 conference abstracts were identified.