Multimodal Imaging of the Normal Eye.

Multimodal imaging is the concept of "bundling" images obtained from various imaging modalities, viz., fundus photograph, fundus autofluorescence imaging, infrared (IR) imaging, simultaneous fluorescein and indocyanine angiography, optical coherence tomography (OCT), and, more recently, OCT angiography. Each modality has its pros and cons as well as its limitations. Combination of multiple imaging techniques will overcome their individual weaknesses and give a comprehensive picture. Such approach helps in accurate localization of a lesion and understanding the pathology in posterior segment. It is important to know imaging of normal eye before one starts evaluating pathology. This article describes multimodal imaging modalities in detail and discusses healthy eye features as seen on various imaging modalities mentioned above.

Foveal Layer Morphology Detected on Spectral Domain Optical Coherence Tomography and its Correlation with Visual Acuity in Asian Indian Premature Infants in their First Year of Life.

PURPOSE: To report foveal microanatomy imaged on handheld spectral domain optical coherence tomography (SDOCT) and correlate it with visual acuity in Asian Indian premature infants. METHODS: A retrospective analysis of 32 Asian Indian premature infants, 10 with Type 2 retinopathy of prematurity (ROP), were imaged between 3 and 12 months of corrected postmenstrual age (PMA) on the handheld SDOCT (Envisu 2300, Bioptigen, DNC, USA). The foveal findings on these images were correlated with visual acuity measured using Teller acuity cards. The study cohort was divided into three groups based on the corrected age, 3-<6 months, 6-<9 months, and 9-12 months. SDOCT images of the foveal center were analyzed for inner retinal layer (IRL) persistence or fusion and presence of the external limiting membrane (ELM), inner segment-outer segment or the ellipsoid zone (EZ), and the outer segment-retinal pigment epithelium (OS-RPE) layers. RESULTS: The mean visual acuity of the three groups was 1.60, 1.63, and 1.23 logMAR, respectively (p < 0.001). Visual acuity significantly correlated with all four layers (IRL fusion, ELM, EZ, and OS-RPE in the 3-<6-month group [p < 0.001], IRL fusion only in 6-<9-month group (p < 0.001), and IRL fusion and EZ in the 9-12-month group (p < 0.001 and p = 0.01, respectively). CONCLUSIONS: The study provides insights into our understanding of a premature infant's foveal maturation in the first year. Inner retinal fusion or maturation is the most important event that correlates with better visual acuity throughout the first year. In addition, between 9 and 12 months PMA, the completion of the EZ at the foveal center positively influenced visual acuity. The presence of ROP did not influence development of the layers, but the sample size was small for subgroup analysis.

An after after-cataract: A curious case of visual axis re-opacification.

Posterior capsular opacification (PCO) is common after cataract surgery. Recurrence is very rare after a successful Yttrium aluminium-garnet (YAG) capsulotomy in adults. We report a case of visual axis re-opacification after a successful YAG capsulotomy for PCO in an adult. A 60-year male underwent phacoemulsification with +20.0 D acrylic hydrophobic intraocular lens implantation and silicon oil removal (SOR) five months after a successful retinal detachment repair. He underwent a capsulotomy after two months of surgery; however, the visual axis re-opacified after three more months. A YAG anterior hyaloidotomy resulted into improved vision which was maintained over further follow-up. In a post-vitrectomy pseudophakic eye, compression by silicon oil on the posterior capsule is lost after SOR, causing easier and faster migration of lens epithelial cells from the equator to the centre forming an early PCO. Recurrence is possible due to the proliferation of lens epithelial cells along anterior hyaloid also. This case highlights the infrequent scenario of visual axis re-opacification and therefore has teaching value for residents and trainee doctors, who should be made aware of this occurrence. Patients should be explained about this possibility when undergoing YAG capsulotomy in complicated cases such as this one.

Author's reply to 'Rickettsia retinitis cases in India: a few comments'.

Diagnosis of rickettsial retinitis remains presumptive when gold standard tests are not available or not done due to financial constrains. History of tick bite followed by fever with skin rash particularly in winter and spring season may point towards Rickettsiosis. The absence of scarring post resolution of rickettsial retinitis suggests inner retinal involvement in contrast to toxoplasmosis. Bilaterality of the disease, 2-4 weeks of latent period, and multifocal nature of retinitis lesions (cotton wool spot-like lesions) especially around the disc and posterior pole may suggest an immune response to recent systemic infection. The use of only antibiotics or only steroids or both together for treatment of rickettsial retinitis is controversial and warrants randomized controlled trials.

Rickettsial retinitis-an Indian perspective.

BACKGROUND: Though rickettsiosis is common in India, there is paucity of rickettsial retinitis (RR) reports from India. Moreover, rickettsial sub-types and their association with retinitis have not been studied. We are reporting a case series of presumed RR with their course of the disease, visual outcome, and association with rickettsial sub-type based on Weil-Felix test. FINDINGS: This is a retrospective study of 19 eyes of 10 patients presented to a single institution. Cases diagnosed with presumed RR were identified from our database from March 2006 to October 2014 and studied retrospectively for patient's demography, clinical presentation, and treatment. Patients with history of fever, retinitis, and a positive Weil-Felix test and a negative chikungunya and dengue serology were diagnosed as presumed rickettsial uveitis. One patient was diagnosed to have epidemic typhus, and four were diagnosed to have Indian tick typhus. Nine patients had bilateral presentation. One patient had history of dog tick bite, and four patients had skin rashes. All the patients presented between 2 and 4 weeks after a fever. CONCLUSIONS: Retinitis on posterior pole with recent history of fever with or without skin rash and a positive Weil-Felix test may suggest a rickettsial etiology. Its ocular manifestation could be an immune response to recent systemic rickettsial infection. Indian tick typhus and epidemic typhus could be the common sub-types seen in our population. Although it has aggressive presentation, it has a good visual prognosis.

Macular edema in Asian Indian premature infants with retinopathy of prematurity: Impact on visual acuity and refractive status after 1-year.

PURPOSE: To report the impact of transient, self-resolving, untreated "macular edema" detected on spectral domain optical coherence tomography in Asian Indian premature infants with retinopathy of prematurity (ROP) on visual acuity (VA) and refraction at 1-year of corrected age. MATERIALS AND METHODS: Visual acuity and refraction of 11 infants with bilateral macular edema (Group A) was compared with gestational age-matched 16 infants with ROP without edema (Group B) and 17 preterms infants without ROP and without edema (Group C) at 3, 6, 9 and 12 months of corrected age using Teller Acuity Cards and cycloplegic retinoscopy. Sub-group analysis of the previously described pattern A and B macular edema was performed. RESULTS: Visual acuity was lower in infants with macular edema compared with the other two control groups throughout the study period, but statistically significant only at 3 months. Visual improvement in these infants was highest between the 3 rd and 6 th month and plateaued by the end of the 1 st year with acuity comparable to the other two groups. The edema cohort was more hyperopic compared to the other two groups between 3 and 12 months of age. Pattern A edema had worse VA compared to pattern B, although not statistically significant. CONCLUSION: Macular edema, although transient, caused reduced VA as early as 3 months of corrected age in Asian Indian premature infants weighing <2000 g at birth. The higher hyperopia in these infants is possibly due to visual disturbances caused at a critical time of fovealization. We hypothesize a recovery and feedback mechanism based on the principles of active emmetropization to explain our findings.

Comparative Evaluation of the Corneal and Anterior Chamber Parameters Derived From Scheimpflug Imaging in Arab and South Asian Normal Eyes.

PURPOSE: To evaluate the differences in the normal corneal and anterior segment Scheimpflug parameters in Arab and South Asian eyes. METHODS: This hospital-based study was performed at a cornea and refractive surgery service in Abu Dhabi. A total of 600 consecutive normal candidates of South Asian (group 1, n = 300) and Arab (group 2, n = 300) origins underwent Scheimpflug imaging (Sirius; Costruzione Strumenti Oftalmici, Italy). One eye was randomly selected for evaluation. RESULTS: The age and sex distributions in both groups were comparable. The pachymetric variables were statistically higher in group 2 (group 2 vs. group 1, 544.3 ± 32.2 µm vs. 535.1 ± 31.4 µm for central corneal thickness, 541.0 ± 32.6 µm vs. 531.9 ± 31.5 µm for minimum corneal thickness, 571.7 ± 43.2 µm vs. 558.1 ± 42.3 µm for apical thickness, and 58.1 ± 4.2 vs. 57.3 ± 4.3 mm³ for the corneal volume; P < 0.05). The anterior chamber volume (group 2 vs. group 1: 166.4 ± 16.4 vs. 161.6 ± 20.5 mm³) and angle (group 2 vs. group 1: 44.6 ± 6.2 vs. 43.5 ± 5.8 degrees) were also higher for group 2 (P < 0.05). Central corneal curvature and apical corneal curvature (apex K) were higher in group 1 (P < 0.05) with comparable astigmatism. The flat keratometry (K), steep K, and apex K were 43.6 ± 2.2 diopters (D), 44.9 ± 1.8 D, and 45.7 ± 1.8 D for group 1, and 43.1 ± 2.2 D, 44.5 ± 2 D, and 45.2 ± 1.9 D for group 2. The effect size (Cohen d) for significant parameters ranged from 0.2 to 0.3. CONCLUSIONS: Normal eyes of Arab ethnicity tend to have statistically thicker and flatter corneas and less-crowded anterior segments than those of the South Asian counterparts. These epidemiological differences have a mild to moderate biological effect size (Cohen d), but they should be considered when evaluating these eyes for anterior segment or corneal procedures.

Urrets-Zavalia syndrome after laser-assisted in situ keratomileusis (LASIK).

We report a case of fixed, non-reactive pupil (Urrets-Zavalia syndrome) in a 34-year-old patient following laser-assisted in situ keratomileusis (LASIK) caused probably by intermittent postoperative intraocular pressure fluctuations. This case highlights the possibility of a fixed and dilated pupil even after LASIK, a technically non-intraocular surgery, which is due to a preventable cause: postoperative intraocular pressure fluctuations. To the best of our knowledge, this is the first report of Urrets-Zavalia syndrome following LASIK.

Implantable collamer lens in a case of corneal scar with anisometropic amblyopia in an adult: an expanded indication.

A 35-year-old man, a unilateral high myope with corneal scarring, presented for evaluation. He had a stromal scar that started temporally, traversed along the pupillary zone partially and extended across the horizontal diameter of the cornea. The Descemet's membrane appeared intact even though the scar was extending into deep stroma towards the nasal end, as seen in the optical coherence tomography image. The patient had an uncorrected distance visual acuity (UDVA) of 4/60 OD, which improved with a refraction of -9.0 DS/-1.50 DC at 15 to 6/18p and 6/6p OS. He underwent an uneventful toric implantable collamer lens (ICL) implantation of -15.0 D/-2.0 D at 102 after preoperative yttrium-aluminium-garnet (YAG) laser iridotomy in the right eye. The postoperative UDVA and corrected distance visual acuity for the right eye were 6/12 and 6/9p (with a refraction of +0.50 D/-0.50 D at 85), respectively. The corneal scar and topography were stable. This case reports an expanded indication for toric ICL in cases with corneal scar/opacity but good spectacle corrected visual acuity.

Universal ocular screening of 1021 term infants using wide-field digital imaging in a single public hospital in India - a pilot study.

PURPOSE: Universal eye screening of neonates is currently not standard of care. Early detection of abnormalities could offer prompt management and a reduction in visual morbidity. We report a pilot study using wide-field digital imaging to screen all infants at birth to explore its feasibility as a tool for universal screening. METHODS: Consecutively enrolled 1021 term infants in a public hospital were imaged within 72 hr of birth using the Retcam shuttle (Clarity MSI, USA). Anterior and dilated posterior segment images were obtained. Infants with abnormal images were examined clinically, and medical or surgical treatment was given when needed, at no cost to the family. RESULTS: Of the 1021 healthy full-term newborns, 48 babies had abnormal findings (4.7%). Retinal haemorrhages were the most common (52.1%) abnormality of which 24% were macular. A 'ridge' resembling retinopathy of prematurity in both eyes constituted 18.8% of all abnormalities. Nine infants (18.8% of abnormalities and 0.9% overall) had conditions meriting medical or surgical intervention and would have been missed otherwise. Seven of these nine babies (0.7%) needed medical attention with a systemic work-up for conditions such as posterior uveitis with linear perivasculitis, salt and pepper retinopathy or posterior synechia. Two of nine babies (0.2%) required surgical intervention for unilateral cataract and retinoblastoma. CONCLUSION: Universal eye screening of all neonates using wide-field digital imaging is possible and safe. Extrapolating our results to the national scenario, we estimate that 226 950 infants requiring treatment would go undiagnosed annually. Universal infant eye imaging strategies must receive serious national consideration.

Management of recurrent postoperative fungal endophthalmitis.

AIM: To report the management of recurrent postoperative fungal endophthalmitis (POFE) after failed pars plana vitrectomy (PPV) and antifungal therapy. SETTINGS AND DESIGN: Tertiary Care Referral Centre in North India. Retrospective, single institution, interventional case-series. MATERIALS AND METHODS: Six patients with microbiologically proven recurrent post-operative fungal endophthalmitis refractory to conventional management were included. The final recurrence was managed with intraocular lens (IOL) explantation and re-PPV. Main outcome measures included preserved globe anatomy, visual acuity and retinal status. 'Anatomical success' defined as preserved anatomy of the globe, and absence of signs of inflammation. Functional success defined as an attached retina and a best corrected visual acuity of better than 20/400. RESULTS: Of the six cases of POFE, five were culture positive [Aspergillus flavus (1), Aspergillus fumigatus (2), Candida albicans (1) and Candida glabrata (1)] and one was smear positive for yeast. All recurred (mean recurrences, 4) despite a mean of 2.17 PPVs and intravitreal amphotericin B. No recurrences were observed after IOL explantation with re - PPV (median follow-up, 37 months). Pre-study defined criteria for successful 'anatomical' and 'functional' outcomes were achieved in 83.3% and 50% respectively. CONCLUSION: This report highlights the effective role of combined IOL explantation with PPV in managing recurrent POFE.

High definition spectral domain optical coherence tomography of retinal pigment epithelial rip in a case of sympathetic ophthalmia.

BACKGROUND: We are reporting a case of granulomatous panuveitis in the right eye following penetrating injury to the left eye. FINDINGS: A 34-year-old female was diagnosed to have sympathetic ophthalmia on treatment with systemic steroids. Vision did not improve in spite of aggressive systemic steroid therapy. On examination, patient had large retinal pigment epithelial rip nasal to the disc with exudative retinal detachment which was documented with FFA, ICG, and OCT. RPE rip is responsible for the persistent exudative retinal detachment in the right eye. CONCLUSIONS: RPE rip can cause decreased vision due to persistence of retinal detachment in a case of sympathetic ophthalmia.

Chikungunya and the eye: a review.

Chikungunya is a self-limited, systemic viral infection that has been a major health problem since the past few years. Ocular manifestations of the disease have become more prevalent in the recent years. Currently, there is neither a specific treatment nor vaccine available for chikungunya fever. This review highlights the current understanding on the pathogenesis, systemic changes with an emphasis on ocular findings, laboratory investigations, and prevention and treatment of this disease.

Anterior segment optical coherence tomography findings of iris granulomas in Hansen's disease: a case report.

BACKGROUND: A 50-year-old male was diagnosed to have a right eye sclerouveitis and left eye granulomatous anterior uveitis due to Hansen's disease. We are reporting the anterior segment optical coherence tomography (ASOCT) findings of iris granuloma in this case. FINDINGS: Skin biopsy revealed plenty of acid fast bacilli with a bacteriological index of 5 suggestive of multibacillary polar lepromatous leprosy. ASOCT revealed well-demarcated smooth-surfaced nodular lesion with internal hyporeflectivity corresponding to the areas of granuloma which decreased in size following treatment with antileprosy drugs and systemic and topical steroids. CONCLUSION: ASOCT is a non-invasive technique to assess the extent of involvement of anterior segment in Hansen's disease and is a useful tool in follow-up. This is also the first report on ASOCT findings of iris granuloma in Hansen's disease.

A novel, low-cost method of enrolling infants at risk for Retinopathy of Prematurity in centers with no screening program: the REDROP study.

PURPOSE: To report the first-year results of the Red Card for Retinopathy of Prematurity (REDROP) study, a low-cost interim strategy to enroll infants into retinopathy of prematurity (ROP) screening where limited expertise exists, piloted at a multi-specialty general hospital. METHODS: Red "warning" cards were placed alongside green "congratulations" cards above the weighing scale in the neonatal unit. Staff weighing the newborn were instructed to give either one of the cards to each mother depending on the weight of the child (≤ 2000 g, red, and > 2000 g, green). Red cards contained information (tri-lingual) about ROP and the venue of screening. Green cards contained general pediatric eye education and recipients were not called. A portion of the red card with the infant's birth date and mother's contact number was retained and collected weekly by volunteers. Mothers were reminded on the mobile phone to come for ROP screening. Screening and treatment were performed free. RESULTS: During the study period, 224 of 805 (27.8%) infants were born ≤ 2000 g. Of these, 169 (75.4%) survived and were eligible for the red card; 91 (53.8%) received it. Of these, 43 (47.3%) infants completed ROP screening, 14 (32.6%) had some stage ROP, and three (6.9%) required laser treatment. The main reason for the lower turnout for screening was the inability to contact mothers on their provided phone numbers. CONCLUSIONS: REDROP demonstrates the feasibility of this low-cost method of enrolling unscreened infants into a ROP program. The cost of enrolling each infant was less than 5 rupees (US$0.10). Suggested strategies to improve use require multi-center validation.

Unilateral conjunctival ulcer due to Stenotrophomonas maltophilia infection.

We report a case of unilateral conjunctival ulcer due to Stenotrophomonas maltophilia infection in an immunocompetent individual. A 44-year-old male presented with complaints of pain and yellowish discharge in the right eye for one week. Patient underwent complete ophthalmic evaluation and relevant laboratory investigations. Anterior segment examination revealed localized conjunctival and episcleral congestion with conjunctival ulceration on the bulbar conjunctiva in the right eye. Gram's stain revealed gram-negative bacilli. Culture and sensitivity revealed S. maltophilia and responded well to topical moxifloxacin with systemic co-trimoxazole therapy.