Quantification of vascular changes in macular telangiectasia type 2 with AngioTool software.

PURPOSE: To compare AngioTool (AT) vascular parameters (VP) between MacTel2 eyes and normal eyes. Secondary outcome measures were to correlate VP with BCVA and to analyze VP between various grades of Simple MacTel Classification. METHODS: This is a retrospective study. SD OCTA images of the superficial vascular complex (SVC) and deep capillary complex (DVC) were exported into Image J and AT. The explant area (EA), vessel area (VA), vessel percentage area (VPA), total number of junctions (TNJ), junction density (JD), total vessel length (TVL), average vessel length (AVL), total number of endpoints (TNE) and mean E lacunarity (MEL) were studied. RESULTS: Group 1 had 120 MacTel2 eyes. Group 2 had 60 age-matched normal eyes. All VP were significantly different between the two groups except EA and TNE in both complexes. None of the VP had a correlation with BCVA. Interquadrant analysis (IQA) in SVC and DVC showed statistical significance in VPA, AVL and JD and in AVL, TNE, JD, VPA respectively. Post hoc analysis in SVC and DVC showed statistical significance in TNJ, JD, TVL and AVL between grade 1 and grade 3, and in VA, VPA, TNJ, JD, TVL and MEL between grade 0 and grade 3 respectively. CONCLUSION: VP were affected in MacTel2 eyes. VP did not correlate with BCVA. Occurrence of pigmentation is an important event in the progression of disease. AT may provide quantitative markers to measure disease progression.

Comparative analysis of outcomes of two (popular) techniques of haptic exteriorization in scleral fixation intra-ocular lens surgery - A retrospective study.

PURPOSE: To compare the visual outcomes and complication rates between the extra-ocular needle-guided haptic insertion technique (XNIT) and the conventional handshake (HS) technique of scleral fixation intra-ocular lens (SFIOL). METHODS: In this retrospective study, we retrieved data of those patients who had undergone SFIOL surgery from January 2018 to May 2022 at our institute for aphakia following either a complicated cataract surgery or an ocular trauma and had a minimum follow-up of 3 months. RESULTS: Of the 156 eyes, the HS technique was done in 80 eyes and the remaining 76 eyes with XNIT. At 3 months follow-up visit, there was no significant difference in the median best corrected visual acuity (BCVA) ( P = 0.988) and uncorrected visual acuity (UCVA) ( P = 0.765) between the two techniques. There was no statistically significant difference between pre-operative median BCVA and post-operative UCVA in XNIT ( P = 0.961) and the HS technique ( P = 0.831) at 3 months follow-up visit. The complication rates between the two techniques were minimal and comparable. The most common post-operative complication was corneal edema. The incidence of cystoid macular edema was slightly more in the XNIT group but not statistically significant ( P = 0.05). Two patients in the HS group developed retinal detachment, which settled after repeat surgery. CONCLUSION: The newer XNIT technique was found to be as safe and effective as compared to the conventional HS technique.

Age-Related Alterations of the Macular Choroid in Healthy Eyes Assessed by Swept-Source Optical Coherence Tomography Angiography.

OBJECTIVE: To analyze age-related changes in the choroid in healthy eyes using swept-source optical coherence tomography angiography (SS-OCTA). PATIENTS AND METHODS: This was a cross-sectional, prospective, observational study enrolling 222 eyes of 116 healthy participants. SS-OCTA images were captured using the PLEX Elite 9000 (Carl Zeiss Meditec) with a 6 x 6 mm pattern centered on the fovea. Subfoveal choroidal thickness (CT) and choroidal volume (CV) were generated automatically through manufacturer tools available in the Advanced Retinal Imaging (ARI) hub network. Choroidal vascularity index (CVI) and choriocapillaris flow deficits (CCFD) were computed using ImageJ. RESULTS: CV was found to be significantly higher in women than men. Overall, there was a significant positive correlation between CVI and CCFD, and a significant negative correlation between CT and CV with age. The relationship, however, was more complex, as a decade-wise analysis showed that CT and CV increased until the second decade, followed by a decrease until the sixth decade, and then an increase again in the seventh and eighth decades. CVI was highest in the seventh decade. In contrast, CCFD increased consistently with age and in all the Early Treatment of Diabetic Retinopathy Study (ETDRS) rings. CONCLUSION: The choroidal blood flow and its thickness reduces as the age advances. While the choroidal flow deficits show a consistent increase with age and the distance from the foveal center, the relationship of other parameters with age is more complex. Having a normative database from healthy subjects is imperative for understanding the changes taking place in diseased states. Choroidal parameters can show significant variations with age. These differences are not uniform or consistent with age, highlighting the importance of a normative reference database to assess the significance of choroidal alterations associated with disease. [Ophthalmic Surg Lasers Imaging Retina 2023;54:526-534.].

Fractal analysis of the macular region in healthy eyes using swept-source optical coherence tomography angiography.

PURPOSE: This cross-sectional observational study evaluated the relationship between retinal vascular fractal dimension (FD) and age, as well as other vascular parameters in healthy eyes using swept-source optical coherence tomography angiography (SS-OCTA). METHODS: The study cohort consisted of 222 eyes of 116 healthy participants with no ocular or systemic disease. SS-OCTA images were captured and analyzed using the Plex Elite 9000 and software tools available in the advanced retinal imaging (ARI) network hub. The retinal vascular layers were defined by the instrument's automatic retinal layer segmentation. The fractal analysis was performed on the superficial capillary plexus (SCP), deep capillary plexus (DCP), and the whole retina. Grayscale OCTA images were standardized and binarized using ImageJ and fractal box-counting analyses were performed using Fractalyse software. Pearson's correlation was used to analyze the correlation between FD and retinal vascular parameters. RESULTS: The results showed that FD values were significantly higher in the 6 mm ring and the whole 6 × 6 scan region when compared to the 1 mm ETDRS central subfield. The correlation between age and FD was weak with a significant positive correlation between age and FD of the SCP in the 6 mm ring and between age and FD of the DCP in the 1 mm ring. Overall, differences in FD values in these healthy eyes were extremely small regardless of age or macular location. CONCLUSION: FD values in normal eyes show little variation with age and are relatively stable across the macula. This suggests that FD values may not need adjustment for age or location when evaluated in the context of retinal disease.

Prescribing patterns of low vision devices in patients with cone-related dystrophies.

Purpose: The aim of this study was to elucidate the type of low vision devices (LVDs) prescribed for patients with cone dystrophy, cone-rod dystrophy, and rod-cone dystrophy and to analyze the visual improvement with the devices. Methods: A retrospective review of 300 electronic medical records of patients with cone dystrophy, cone-rod dystrophy, and rod-cone dystrophy referred to the low vision care (LVC) clinic for the first time between 2014 and 2016 at a tertiary eye care center was done. Collected data included the demographic profile of patients, details of LVDs, and best-corrected vision. Results: Out of 300 patients, 62.6% (n = 188) were male and 37.3% (n = 112) were female. Of the cases, 50% (n = 150) had cone-rod dystrophy, 45% (n = 135) had cone dystrophy, and 5% (n = 15) had rod-cone dystrophy. The most commonly prescribed LVD was SEE-TV binocular telescope (n = 6, 2.0%) for distance and dome magnifier (n = 60, 20%) for near. ET-40 dark grey tint (20.6%) was preferred for managing photophobia. There was a statistically significant difference in both distance and near visual acuities with LVDs (P < 0.05) in all categories, except rod-cone dystrophy. Conclusion: Early diagnosis with appropriate prescription of LVDs including tints helps in achieving good quality of vision in patients with cone-related dystrophies.

Choriocapillaris flow deficits in polypoidal choroidal vasculopathy using swept source optical coherence tomography angiography.

Purpose: To evaluate the choriocapillaris flow deficits (CCFD) on swept-source optical coherence tomography angiography (SS-OCTA) in eyes with unilateral polypoidal choroidal vasculopathy (PCV), fellow unaffected eyes, and to compare them with age-matched healthy controls. Methods: This study was a cross-sectional study which included treatment-naïve eyes with unilateral PCV (group 1), fellow unaffected eyes of patients with PCV (group 2), and normal eyes (group 3). Using the SS-OCTA, the Choriocapillaris (CC) slab was segmented from the structural optical coherence tomography (OCT) and the corresponding flow map was multiplied after signal compensation. The resultant image was evaluated for CCFD in equidistant squares measuring 1 × 1 mm, 1.5 × 1.5 mm, 2 × 2 mm, 2.5 × 2.5 mm, 3 × 3 mm, and 6 × 6 mm centered on the fovea. Results: The percentage of flow deficits were significantly increased (one-way ANOVA, P = 0.003 and P = 0.049) in the eyes with PCV as compared to the fellow eyes, and age-matched healthy controls. In the multiple pairwise comparison using post hoc Bonferroni, CCFD of 1 mm in group 1 and 2 (P = 0.019), group 1 and 3 (P = 0.003), and CCFD of 1.5 mm in group 1 and 3 (P = 0.044) were statistically significant. Correlation analysis showed no significant correlation between CCFD, age, Best corrected visual acuity (BCVA), foveal thickness (FT), and subfoveal choroidal thickness (SFCT) in our study. Linear regression analysis showed that the CCFD was negatively correlated with the distance from the foveal center in group 1 (ß = -0.613, P = 0.046). Conclusion: Eyes with PCV demonstrated a significant flow impairment in the choriocapillaris layer as compared to the fellow unaffected eyes and age-matched healthy eyes.