Validation of an automated method for studying retinal capillary blood flow.

Two major approaches for tracking cellular motion across a range of biological tissues are the manual labelling of cells, and automated analysis of spatiotemporal information represented in a kymograph. Here we compare these two approaches for the measurement of retinal capillary flow, a particularly noisy application due to the low intrinsic contrast of single red blood cells (erythrocytes). Image data were obtained using a flood-illuminated adaptive optics ophthalmoscope at 750 nm, allowing the acquisition of flow information over several cardiac cycles which provided key information in evaluating tracking accuracy.

Mapping the human parafoveal vascular network to understand flow variability in capillaries.

Capillary flow is known to be non-homogenous between vessels and variable over time, for reasons that are poorly understood. The local properties of individual vessels have been shown to have limited explanatory power in this regard. This exploratory study investigates the association of network-level properties such as vessel depth, branch order, and distance from the feeding arteriole with capillary flow.

Flow Heterogeneity and Factors Contributing to the Variability in Retinal Capillary Blood Flow.

Purpose: Capillary flow plays an important role in the nourishment and maintenance of healthy neural tissue and can be observed directly and non-invasively in the living human retina. Despite their importance, patterns of normal capillary flow are not well understood due to limitations in spatial and temporal resolution of imaging data.

Methods: Capillary flow characteristics were studied in the retina of three healthy young individuals using a high-resolution adaptive optics ophthalmoscope.

Phenotypic heterogeneity in family members of patients with retinitis pigmentosa.

Purpose: To describe the phenotypic variations in family members of patients with retinitis pigmentosa (RP) with different modes of inheritance and to assess the ocular abnormalities in RP families.

Methods: A descriptive analysis of three types of inheritance of RP was carried out, where 64 family members were examined at a tertiary eye care center, South India. They underwent comprehensive eye examination, fundus photography, fundus autofluorescence (FAF), full-field electroretinogram (FFERG), and spectral domain optical coherence tomography (SD-OCT).

Management of macular edema with branch retinal vein occlusion in a case of secondary polycythemia.

We report a case of polycythemia with an ocular complication of branch retinal vein occlusion associated with macular edema that was managed by anti-vascular endothelial growth factor (VEGF) and systemic management. A 43-year-old, one-eyed male, a known case of polycythemia presented with complaints of decreased vision in the right eye. He underwent comprehensive eye evaluation, fundus photography and optical coherence tomography at the baseline visit and post intravitreal ranibizumab 1-, 3-, 4- and 11-month follow-up.

Long-term outcomes following primary intraocular lens implantation in infants younger than 6 months.

Purpose: To study the long-term safety profile and visual outcomes of primary intraocular lens (IOL) implantation in infants <6 months of age.

Methods: This was a retrospective observational study conducted at a tertiary eye care center in South India. Infants under 6 months meeting the selection criteria who underwent cataract surgery (lens aspiration, primary posterior capsulorhexis, and anterior vitrectomy) with primary IOL implantation between January 2008 and December 2011 and minimum 3-year follow-up were included.

Understanding variable disease severity in X-linked retinoschisis: Does RS1 secretory mechanism determine disease severity?

X-linked retinoschisis (XLRS) is a retinal degenerative disorder caused by mutations in RS1 gene leading to splitting of retinal layers (schisis) which impairs visual signal processing. Retinoschisin (RS1) is an adhesive protein which is secreted predominantly by the photoreceptors and bipolar cells as a double-octameric complex. In general, XLRS patients show wide clinical heterogeneity, presenting practical challenges in disease management.

Clinical and genetic analysis of Indian patients with NDP-related retinopathies.

Purpose: NDP-related retinopathies are a group of X-linked disorders characterized by degenerative and proliferative changes of the neuroretina, occasionally accompanied with varying degrees of mental retardation and sensorineural hearing loss. NDP is the predominant gene associated with NDP-related retinopathies. The purpose of this study was to report the clinical and genetic findings in three unrelated patients diagnosed with NDP-related retinopathies.

Genetic studies in a patient with X-linked retinoschisis coexisting with developmental delay and sensorineural hearing loss.

Background: In this study, we present a juvenile retinoschisis patient with developmental delay, sensorineural hearing loss, and reduced axial tone. X-linked juvenile retinoschisis (XLRS) is a retinal dystrophy, most often not associated with systemic anomalies and also not showing any locus heterogeneity. Therefore it was of interest to understand the genetic basis of the condition in this patient.

Proteomic profiling of human intraschisis cavity fluid.

Background: X-linked retinoschisis (XLRS) is a vitreoretinal degenerative disorder causing vision deterioration, due to structural defects in retina. The hallmark of this disease includes radial streaks arising from the fovea and splitting of inner retinal layers (schisis). Although these retinal changes are attributed to mutations in the retinoschisin gene, schisis is also observed in patients who do not carry mutations.

STRUCTURAL AND FUNCTIONAL CHARACTERIZATION OF BENIGN FLECK RETINA USING MULTIMODAL IMAGING.

Purpose: To report structural and functional features in a case series of benign fleck retina using multimodal imaging.

Methods: Four cases with benign fleck retina underwent complete ophthalmic examination that included detailed history, visual acuity, and refractive error testing, FM-100 hue test, dilated fundus evaluation, full field electroretinogram, fundus photography with autofluorescence, fundus fluorescein angiography, and swept-source optical coherence tomography.

Results: Age group of the cases ranged from 19 years to 35 years (3 males and 1 female).

Retinal sensitivity changes associated with diabetic neuropathy in the absence of diabetic retinopathy.

Purpose: To explore any relationship between the markers of early retinal neuronal damage and peripheral diabetic neuropathy in subjects with no diabetic retinopathy (DR).

Methods: A cross-sectional study in which type 2 diabetic subjects (n=743) without DR were studied. Visual functions including visual acuity, contrast sensitivity, colour vision, retinal sensitivity using microperimeter and retinal thicknesses by spectral domain optical coherence tomography were measured.

Phenotypic characterization of X-linked retinoschisis: Clinical, electroretinography, and optical coherence tomography variables.

Aims: To study the phenotypic characteristics of X-linked retinoschisis (XLRS) and report the clinical, electroretinogram (ERG), and optical coherence tomography (OCT) variables in Indian eyes.

Design: A retrospective study.

Materials And Methods: Medical records of 21 patients with retinoschisis who were genetically confirmed to have RS1 mutation were reviewed.

Prenatal genetic diagnosis of retinoblastoma--clinical correlates on follow-up.

Retinoblastoma is the most common malignant intraocular tumor in pediatric age group if undetected leads to ocular mortality. Prenatal diagnosis is an emerging technology to detect fatal diseases in utero such that subsequent management is planned to reduce the ocular morbidity. We describe a case demonstrating the importance of prenatal diagnosis in a child with a strong family history of retinoblastoma and importance of a long-term clinical follow-up in these cases.

Microperimetry biofeedback training in a patient with bilateral myopic macular degeneration with central scotoma.

Microperimetry-1 (MP-1) evaluation and MP-1 biofeedback training were done in a case of bilateral myopic macular degeneration with a central scotoma. Fixation behavior, location and stability of preferred retinal locus, eye movement speed, and mean sensitivity were assessed. The mean retinal sensitivities before, after and at 1-year after training in the right eye were 2.