Rajani Battu

Subthreshold micropulse yellow laser (577 nm) in chronic central serous chorioretinopathy: safety profile and treatment outcome.

PurposeTo assess the safety and efficacy of a single session of subthreshold micropulse (SM) yellow laser (577 nm) in the treatment of chronic central serous chorioretinopathy (CSCR).MethodsThis was a retrospective analysis of 15 eyes of 13 patients with CSCR of >3 months duration who had been treated with SM yellow laser (577 nm). All patients had been treated using multiple spots of laser with a duty cycle of 10% over areas of focal and diffuse leak, as seen on fundus fluorescein angiography (FFA) and indocyanine green angiography (ICGA). Reduction in subretinal fluid height on spectral domain optical coherence tomography (SD-OCT) was used to measure the response to treatment.ResultsThe mean follow-up was at 8 weeks (4–19 weeks). All eyes responded to treatment. The mean subretinal fluid height pre and post treatment was 232 and 49 μm, respectively, showing a 79% average reduction (P<0.001) in fluid height. There was no evidence of retinal pigment epithelium or retinal damage on SD-OCT, FFA, or fundus autofluorescence. Median visual improvement was one line on Snellen’s visual acuity chart (P=0.015). Microperimetry was performed in eight eyes of which six eyes (75%) showed an improvement in the threshold values post treatment.ConclusionSM yellow laser is an effective treatment option for chronic CSCR.

Optical coherence tomography as a tool to evaluate retinal changes in Parkinson's disease.

BACKGROUND Though Parkinsons disease (PD) is primarily a disease of the basal ganglia, recent evidence suggests that PD affects the retina. OBJECTIVE The study was designed to evaluate the thickness of retinal nerve fiber layer (RNFL) and thickness and volume of the macula in PD and hence explore the utility of optical coherence tomography (OCT) in studying retinal changes in PD. METHODS A prospective, hospital based evaluation of 30 patients with PD and 30 healthy controls was carried out. Various parameters such as RNFL, central macular thickness (CMT), central and total macular volumes (TMV) and retinal thickness were analyzed using OCT. RESULTS (a) RNFL thickness was not significantly different between the patients and controls. A significant negative correlation was found between the RNFL thickness in the right nasal superior sector and the UPDRS motor score. (b) CMT was found to be significantly reduced in the right eye and a negative correlation with the UPDRS motor score was noted. (c) TMV was significantly greater in patients compared to the controls. (d) The outer retinal layer in the right nasal quadrant and the right inferior quadrants were found to be significantly thinner in patients with PD. CONCLUSIONS We did not find any significant abnormality in the RNFL thickness in patients with PD. Decreased CMT in patients with PD and a significant negative correlation of RNFL thickness and CMT with severity of PD suggest a remote possibility of dopaminergic depletion in the retina. However long term studies are warranted to validate our findings.

Postoperative endophthalmitis caused by sequestered Acinetobacter calcoaceticus

PURPOSE To describe postoperative endophthalmitis caused by sequestered Acinetobacter calcoaceticus. METHOD Case report. A 40-year-old woman developed recurrence of inflammation after extracapsular cataract extraction with intraocular lens (IOL) implantation. At last recurrence, the capsular bag was studded with white deposits. Intraocular lens was removed along with capsular bag during pars plana vitrectomy. RESULTS The capsular bag, when cultured, grew A calcoaceticus. The media remained clear with no evidence of recurrence of infection over a 3-month follow-up. CONCLUSION Postoperative endophthalmitis similar to that caused by sequestered Propionibacterium acnes can be caused by A calcoaceticus.

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 attempt 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.

Retinal oxygen saturation in retinitis pigmentosa and macular dystrophies in asian-Indian eyes.

PURPOSE To study the oxygen-saturation profiles in RP and macular dystrophies and compare them with age-matched healthy controls. METHODS In a cross-sectional prospective study, 62 subjects with RP, 23 with macular dystrophies, and 78 controls were enrolled, and retinal oximetry was performed with the Oxymap T1 retinal oximeter. The images were analyzed for oxygen saturation and diameter of retinal vessels. RESULTS All parameters showed a significant difference among the three groups. Patients with RP showed significantly lower diameters (98.4 μm and 136.9 μm arteriolar and venous) (P < 0.001), higher saturations (102.3% and 59.1%) (P < 0.001; 0.06), and higher arterio-venous saturation difference (AVSD) (43%) (P < 0.001) compared with the other two groups. Macular dystrophies showed higher global arteriolar values (96.7%) and AVSD (41.6%) but comparable venous values (54.9%) to the control group (90.6%, 57.4%, and 33.3%). CONCLUSIONS Oximetry is sensitive in quantifying hemodynamic changes in retinal dystrophies. It is still unclear whether these hemodynamic changes are a cause or a result of the disease process.

Melanoma associated retinopathy: A new dimension using adaptive optics.

We report a 56-year-old male patient, complaining of metamorphopsia in his left eye nevertheless visual acuity, slit lamp, and fundus examinations were within normal limits. Microperimetry (MAIA, Centervue, Italy) revealed central field loss and spectral domain optical coherence tomography (Spectralis, Heidelberg, Germany) showed disrupted cone outer segment tip layer. The patient had a diagnosis of cutaneous melanoma in his foot for which an excision biopsy with lymph node dissection was performed 5 months earlier. Our clinical diagnosis was melanoma-associated retinopathy. Electrophysiology confirmed the diagnosis. Adaptive optics retinal imaging (Imagine eyes, Orsay) was performed to assess the cone mosaic integrity across the central retina. This is the first report on the investigation of autoimmune retinopathy using adaptive optics ophthalmoscopy. This case highlights the viability of innovative diagnostic modalities that aid early detection and subsequent management of vision threatening retinal.

Challenges of managing retinal dystrophies: An experience from south India

Generally considered as ‘rare’ or ‘orphan’ diseases, retinal dystrophies are highly prevalent in India, in part because of the high rate of consanguinity. For example, the prevalence of retinitis pigmentosa in the US is estimated to be 1 in 3500, compared to an estimate of 1 in 372–930 in southern India. This is similar to the situation in other Asian countries, like Pakistan. As opposed to Western countries, the clinical science of eye genetics and the practice of genetic counseling are still developing specialties in India. Physicians/genetic counselors who are specialized or trained to deal with these conditions are scarce. Molecular genetic testing is either inaccessible or unaffordable to the majority of patients. Consanguinity and arranged marriages are an accepted norm, especially in southern India. In addition, opportunities for rehabilitation of severely visually impaired persons are limited. Consequently, managing patients with retinal dystrophies presents specific clinical and psychosocial challenges in India.

Adaptive optics imaging of the outer retinal tubules in Bietti's crystalline dystrophy

PurposeTo study the outer retinal tubules using spectral domain optical coherence tomography and adaptive optics and in patients with Bietti’s crystalline dystrophy.MethodsTen eyes of five subjects from five independent families with Bietti’s crystalline Dystrophy (BCD) were characterized with best-corrected visual acuity (BCVA), full-field electroretinography, and fundus autofluorescence (FAF). High-resolution images were obtained with the spectral domain optical coherence tomography (SD-OCT) and adaptive optics (AO).ResultsSD-OCT showed prominent outer retinal layer loss and outer retinal tubulations at the margin of outer retinal loss. AO images displayed prominent macrotubules and microtubules with characteristic features in eight out of the 10 eyes. Crystals were present in all ten eyes. There was a reduction in the cone count in all eyes in the area outside the outer retinal tubules (ORT).ConclusionsThis study describes the morphology of the outer retinal tubules when imaged enface on the adaptive optics in patients with BCD. These findings provide insight into the macular structure of these patients. This may have prognostic implications and refine the study on the pathogenesis of BCD.