Analysis of foveal avascular zone by using spectral-domain optical coherence tomography angiography in healthy Indian eyes.

PURPOSE: To analyze FAZ superficial (s) and deep (d) area and dimensions by using spectral-domain optical coherence tomography angiography (OCTA) in healthy eyes and to assess effect of age, gender, axial length (AL), central foveal thickness (CFT), and central choroidal thickness (CCT) on FAZ. We aimed to study FAZ dimensions with OCTA in healthy Indian eyes with the purpose of creating a normative database. SETTINGS AND DESIGN: Observational cross-sectional study. METHODS: In total, 200 healthy eyes in the age group of 20-60 years having best corrected visual acuity better than 6/12 (Snellen's) with no systemic illness/intraocular surgery were included. FAZ parameters were calculated using OCTA, and the same was evaluated for any correlation with different ocular parameters mentioned above. The data were reported as frequencies/percentages and mean ± SD. The association between quantitative variables was evaluated using Pearson's correlation coefficient. RESULTS: The dFAZ area (0.56 ± 0.12 mm 2 ) was larger than the sFAZ area (0.42 ± 0.13 mm 2 ). Females had larger FAZ than males. AL and CFT had a negative correlation, whereas CCT had a positive correlation with FAZ. Age did not influence FAZ. sFAZ and dFAZ varied significantly in healthy eyes. CONCLUSION: FAZ parameters calculated using OCTA in healthy Indian eyes suggested that the area and dimensions in both SCP and DCP are larger in individuals from the Indian subcontinent when compared to other parts of the world. FAZ area and dimensions, when compared to previous studies, were variable. Thus, there is a need to establish normative data for ethnicity for proper interpretation of FAZ using OCTA.

Coexistent Rosai Dorfman disease and Langerhans cell histiocytosis in an Orbital mass: A Case Report.

INTRODUCTION: Rosai Dorfman disease (RDD) is a rare benign histiocytic proliferative disorder of lymph node sinuses. Langerhans cell histiocytosis (LCH) is a solitary or multisystem clonal proliferation of abnormal dendritic cells (Langerhans cells) with varied presentations. The co-occurrence of these two entities is quite rare. CASE DESCRIPTION: A six-year-old boy presented with multiple mass lesions in the neck since two years and a nodular lesion in right upper eyelid for the past 4 months. He was diagnosed with tubercular lymphadenitis 2 years back, and was given a course of anti-tubercular therapy (ATT) elsewhere. No improvement was seen. Fine needle aspiration cytology (FNAC) of the cervical lymph nodes revealed reactive lymphadenitis while lymph node biopsy showed features of RDD. Excision biopsy of the orbital mass showed features of both RDD and LCH. The patient was started on tablet prednisolone. Six months later, complete resolution of lymph node enlargement and remaining orbital mass was noted. Post operative contrast enhanced Magnetic Resonance Imaging of head and neck was normal. CONCLUSION: The coexistence of RDD and LCH may be a result of divergent differentiation from a common lineage or a de novo phenotypic evolution.

Comparison of optical biometry and conventional acoustic biometry in the axial length measurement in silicone oil-filled eyes.

Purpose: To compare the axial length (AL) obtained by A-scan biometry (PAC SCAN 300AP; Sonomed Escalon, USA) and LENSTAR-LS 900 (Haag-Streit, Koeniz, Switzerland) in silicone oil (SiO)-filled eyes. Methods: AL measurements were taken in 50 SiO-filled eyes using A-scan and LENSTAR-LS 900 before SiO removal and 1 month following SiO removal. In the subset of patients requiring intraocular lens (IOL) insertion, the predicted refraction and the refraction obtained were compared. IOL power in these patients was calculated using SRK-T formula and the AL obtained by LENSTAR. Results: In SiO-filled eyes, a significant difference was noted between the AL values obtained using the two methods (P = 0.0002). No significant difference was noted after SiO removal (P = 0.634). In the subset of patients needing IOL insertion, no significant difference (P = 0.07) was seen between target refractive error and postoperative refractive error (mean deviation from the target being 0.176 diopter). AL of an SiO-filled eye is more accurately measured using optical low coherence reflectometry (OLCR)-based biometry (LENSTAR) than with conventional acoustic biometry (A-scan). Conclusion: We conclude that LENSTAR gives more accurate biometry in an SiO-filled eye. The AL obtained after SiO removal was comparable and showed no significant difference.

Orbital tumour or a retained foreign body? An uncommon case of missed diagnosis.

We report a case who presented with decreased vision, significant hypotropia, proptosis and gross limitation of extraocular motility for one year. Suspecting an orbital tumour, we asked for a computed tomography of the orbit which revealed a mass lesion in the inferior orbit. However, incisional biopsy reported inflammatory infiltration. Diagnosing it as orbital inflammatory disease, a course of oral steroids was given for four weeks. It was only after the reduction in inflammation that a foreign body was palpable in the inferior fornix. Surgical exploration revealed a large wooden foreign body measuring 3.3 × 1 × 0.3 cm. Though intraorbital foreign bodies are not rare, ambiguous history, delayed presentation and nonspecific CT findings made this case diagnostically challenging.

Comparison of fundus fluorescein angiography, optical coherence tomography and optical coherence tomography angiography features of macular changes in Eales disease: a case series.

PURPOSE: To study the macular features in Eales disease patients observed with fundus fluorescein angiography (FA), optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA). METHODS: A cross-sectional study was done on treatment naïve 31 eyes (23 patients) with Eales disease. Baseline parameters such as Best-corrected visual acuity (BCVA), slit-lamp bio microscopy (SLB), indirect ophthalmoscopy, FA, spectral-domain OCT {quantitative (central macular thickness [CMT]) and qualitative analysis on SD-OCT} and OCTA were performed. Any media opacity precluding the above investigations was excluded. RESULTS: Macular findings comprised of- epiretinal membrane, macular exudation, full thickness macular hole, sub internal limiting membrane bleed, cystoid macular oedema, neurosensory detachment and retinal thickening. Sixteen (51.6%) of our patients had macular changes as seen on all modalities together. SLB and indirect ophthalmoscopy missed macular findings in 50% patients and FA in 18.8% patients. OCT and OCTA diagnosed all macular findings. On comparison of mean BCVA in patients with macular involvement on FA, OCT and OCTA, compared to those without macular involvement, patients with macular involvement had lower BCVA (p 0.000, 0.01 and 0.001 respectively). Thus, FA missed many patients who had significant macular involvement and hence less vision. CONCLUSION: Eales disease though described in literature as classically being peripheral retina disease process, also has macular involvement. OCT and OCTA are useful guides to evaluation of macular involvement in these patients. The latter seems to be superior to FA in detecting macular abnormalities in this ailment. OCTA is non-invasive and shows deep capillary plexus changes which are not shown by any other modality.

Compliance to topical anti-glaucoma medications among patients at a tertiary hospital in North India.

PURPOSE: The present study aims to estimate the prevalence of non-compliance and improper drop administration technique among glaucoma patients and describe common obstacles to medication compliance. METHODS: A hospital-based cross-sectional study, using standardized questionnaire and direct observation by study personnel was conducted among glaucoma patients aged 18 years and above at a tertiary care charitable eye hospital in North India. 151 consecutive glaucoma patients on medical therapy following up at the glaucoma clinics for at least 6 months were recruited. Non-compliance was defined as missing at-least one drop of medication per week and (or) the inability to accurately describe the medication regimen. Study personnel also assessed drop administration technique during application of eye drops by patients treating ophthalmologist-provided information, including measures of disease stability. Factors such as socioeconomic status, presence of caregiver, and number of medications with their effect on compliance were studied using chi-square statistics. RESULTS: Among 151 patients interviewed, around 49% of patients reported problems in using glaucoma medications, with 16% of them reporting total non-compliance. 35% of patients demonstrated improper drop administration technique. Forgetfulness was cited as the main reason for being non-compliant and had a significant association with non-compliance (P = 0.00). Paying patients were more compliant as compared to subsidized patients (P = 0.05). Disease was more stable in compliant patients compared to non-compliant patients (P = 0.05). No other factor had significant association with compliance (P > 0.05). CONCLUSIONS: Over 50% of the patients surveyed were non-compliant, and 35% demonstrated improper administration technique. Glaucoma patients should be educated on the importance of compliance and aids that minimize forgetfulness, and delivery systems facilitating the delivery of medications to the eye could be considered to enhance patient adherence.