Three-dimensional choroidal contour mapping in healthy population.

Purpose was to study 3-dimensional choroidal contour at choroidal inner boundary (CIB) and choroidal outer boundary (COB) in healthy eyes. Healthy eyes imaged on wide field swept-source optical coherence tomography were included. Delineation of CIB and COB was done based on our previously reported methods. Quantitative analysis of the surfaces of CIB and COB was based on analyzing best fit spherical radius (R) (overall and sectoral). One hundred and seven eyes of 74 subjects with a mean age of 46.4 ± 19.3 years were evaluated. Overall, R COB (mean ± SD: 22.5 ± 4.8 mm) < R CIB (32.4 ± 9.4 mm). Central sector had the least R at COB (7.2 ± 5.9 mm) as well as CIB (25.1 ± 14.3 mm) across all age groups. Regression analysis between R (CIB) and age (r = -0.31, r2 = 0.09) showed negative correlation (P < 0.001) and that between R (COB) and age was positive (r = 0.26, r2 = 0.07) (P = 0.01). To conclude, central sector is the steepest sector in comparison to all the other sectors. This is indicative of a prolate shape of choroidal contour at CIB and COB. Outer boundary of choroid is steeper than inner boundary across all age groups. However, with ageing, outer boundary becomes flatter and inner boundary becomes steeper.

Pigment epithelial detachment composition indices in central serous chorioretinopathy as a biomarker for disease activity: A computational methodology and 1 year outcomes.

PURPOSE: Investigation of pigment epithelial detachment (PED) characteristics in central serous chorioretinopathy (CSCR) is underrepresented in the literature. We present a novel computational approach to quantify PED composition indices (PEDCI) in CSCR and track changes over time. METHODS: 34 eyes with active CSCR were analyzed quarterly over a 1-year period. Cases were categorized into acute and chronic CSCR depending on a symptom duration of less than 3 months or more than 3 months respectively. PED, retinal and choroidal dimensions were manually measured, and interval changes were compared using repeated measures of variance ANOVA. PED composition analysis involved manual segmentation followed by automated sub segmentation of PED areas to identify serous, neovascular and fibrous tissues. PEDCI for each component was compared among cases of acute and chronic CSCR. RESULTS: CMT and NSD-h decreased by 65.2 µm (p = 0.01), and 86.5 µm (p < 0.01) respectively at 12 months. At baseline, 7/17 acute CSCR eyes and 8/15 chronic CSCR eyes had a concomitant PED; acute cases had both serous and neovascular components (PEDCI-S: 16.95%, PEDCI-N: 40.3%), whereas chronic cases only had a neovascular component (PEDCI-S: 0%, PEDCI-N: 30.5%). At 12-month follow-up, 6/7 of acute CSCR group and 6/8 chronic CSCR group had a concomitant PED; PEDCI-S was largest for acute CSCR (53.4%) and PEDCI-N was largest for chronic CSCR (46.7%). CONCLUSION: We identify a novel biomarker PEDCI to differentiate acute and chronic CSCR with higher PEDCI-S in acute CSCR, and higher PEDCI-N in chronic CSCR.

Comparison of pigment epithelium detachment composition indices between neovascular age-related macular degeneration and polypoidal choroidal vasculopathy.

PURPOSE: To compare changes in the fibrous component of pigment epithelium detachment composition indices (PEDCI-F) in neovascular age-related macular degeneration (n-AMD) and polypoidal choroidal vasculopathy (PCV) over 12 months. METHODS: This was a retrospective chart review of treatment-naïve n-AMD and PCV eyes treated with anti-vascular endothelial growth factor (anti-VEGF) agents. Optical coherence tomography (OCT) images were recorded at baseline and at 3, 6, and 12 months. OCT images were processed by filtering followed by pigment epithelium detachment (PED) segmentation and analysis of PED lesion heterogeneity based on the composition (PEDCI-F). RESULTS: A total of 74 eyes with n-AMD (36) and PCV (38) were included. Overall, PEDCI-F increased minimally in both n-AMD and PCV groups (both p > 0.05). The majority, i.e., 58.3% and 60.5%, of n-AMD and PCV eyes, respectively, showed an increase in PEDCI-F at 12 months. An increase in PEDCI-F was associated with improved BCVA logMAR (n-AMD, r = -0.79; p < 0.001 and PCV, r = - 0.06; p = 0.74) and the need for fewer anti-VEGF injections (n-AMD, r = - 0.53; p < 0.001 and PCV, r = - 0.09; p = 0.58). CONCLUSION: PEDCI-F increases in the majority of eyes with n-AMD and PCV through 12 months following treatment with anti-VEGF injections. This group had better visual acuity compared to the other subset with reduction in PEDCI-F requiring more anti-VEGF injections and worse visual acuity, possibly due to fibrovascular PED (FVPED) collapse and atrophy or a relative increase in other PEDCI constituents at 12 months.

Longitudinal changes in pigment epithelial detachment composition indices (PEDCI): new biomarkers in neovascular age-related macular degeneration.

PURPOSE: To evaluate novel, automated biomarkers, pigment epithelial detachment composition indices (PEDCI) in eyes with neovascular age-related macular degeneration (nAMD) undergoing anti-vascular endothelial growth factor (anti-VEGF) therapy through 24 months. METHODS: Retrospective analysis of 37 eyes (34 patients) with PED associated with nAMD receiving as-needed anti-VEGF treatment was performed. Best-corrected visual acuity (BCVA) and optical coherence tomography images were acquired at a treatment-naïve baseline and 3-, 6-, 12-, 18-, and 24-month visits. Previously validated automated imaging biomarkers, PEDCI-S (serous), PEDCI-N (neovascular), and PEDCI-F (fibrous) within PEDs were measured. ANOVA analysis and Spearman correlation were performed. RESULTS: Mean BCVA (in logMAR) was 0.60 ± 0.47, 0.45 ± 0.41, 0.49 ± 0.49, 0.61 ± 0.54, 0.59 ± 0.56, and 0.67 ± 0.57 at baseline, 3, 6, 12, 18, and 24 months respectively. Overall, BCVA showed minimal worsening of 0.07 ± 0.54 logMAR (p = 0.07). 13.38 ± 3.77 anti-VEGF injections were given through 24 months. PEDCI-F showed an increase of 0.116, 0.122, 0.036, and 0.006 at months 3, 6, 12, and 18 respectively and a decrease of 0.004 at month 24 (p = 0.03); PEDCI-S showed a decrease of 0.064, 0.130, 0.091, 0.092, and 0.095 at months 3, 6, 12, 18, and 24 respectively (p = 0.16); PEDCI-N showed a decrease of 0.052 at month 3 and an increase of 0.008, 0.055, 0.086, and 0.099 at months 6, 12, 18, and 24 respectively (p = 0.06). BCVA was negatively correlated with PEDCI-F (r = -0.28, p < 0.01), and positively correlated with PEDCI-N (r = 0.28, p < 0.01) and PEDCI-S (r = 0.15, p = 0.03). CONCLUSION: Longitudinal analysis of PEDCI supports their utility as biomarkers that characterize treatment related effects by quantifying the relative composition of PEDs.

Peripapillary fluid: Obvious and not so obvious!

Intraretinal or subretinal fluid in the peripapillary area can be clinically visualized in conditions such as peripapillary choroidal neovascularization, optic disc pit maculopathy, and optic nerve head tumors and granulomas. Optical coherence tomography (OCT) helps to visualize peripapillary fluid in many other chorioretinal conditions such as peripapillary pachychoroid syndrome, posterior uveitis, central retinal vein occlusion, malignant hypertension, hypotonic maculopathy as well as neuro-ophthalmological conditions such as glaucoma, microcystic macular edema and disc edema due papilledema, non-arteritic anterior ischemic optic neuropathy, neuroretinitis, and diabetic papillopathy. Often, the differential diagnosis of peripapillary fluid is a bit tricky and may lead to misdiagnosis and improper management. We describe a diagnostic algorithm for peripapillary fluid on OCT and outline the salient features and management of these conditions.

Novel pharmaceuticals for the management of retinal vein occlusion and linked disorders.

INTRODUCTION: Retinal vein occlusion (RVO) is the second leading cause of blindness from retinal vascular disease behind diabetic retinopathy. Anti-vascular endothelial growth factor (VEGF) and glucocorticoid therapy are the cornerstones of pharmaceutical treatment for RVO. There is considerable interest in developing new pharmaceuticals in and out of these two classes to reduce costs, lower injection burden, and treat the occlusion itself, rather than the complications. AREAS COVERED: In this review, we discuss novel pharmaceuticals for the treatment of RVO outside of current standard of care. We performed a comprehensive literature search encompassing pharmaceuticals that have recently been approved or have shown promising results in early clinical trials or animal models. EXPERT OPINION: Anti-VEGF therapy remains the most efficacious treatment for RVO with a very favorable side effect profile. New biosimilars reduce costs while maintaining efficacy. Novel glucocorticoids may be a useful therapy in patients for whom anti-VEGF therapy has failed, or as an adjunct. Pharmaceuticals in other drug classes, particularly those with neuroprotective or regenerative properties, as well as those geared toward treating the occlusion itself, represent exciting options for early RVO therapy, but are likely years away from clinical relevance.

Bilateral evolution of OCT biomarkers in dry AMD: Long-term follow up study.

PURPOSE: To report the emergence and progress of four late-stage characteristics: incomplete retinal pigment epithelium and outer retinal atrophy (iRORA) and complete RPE and outer retinal atrophy (cRORA), drusen ooze and drusen collapse in eyes with dry age-related macular degeneration (AMD) using Spectral Domain Optical Coherence Tomography (SD-OCT). METHODS: This was a retrospective analysis of eyes with non-exudative AMD. Multimodal imaging was done at follow up visits ≤ 12 months. OCT volume scan was used to assess and identify the 4 characteristics. Univariate analysis was done for the various demographic and clinical characteristics.Patients with a mean age of 76.7 ± 10 years were followed up for 69.9 ± 20.6 months. iRORA, cRORA, drusen ooze was present in 15.6%, 15.6% and 15.6% of patients at baseline, respectively, and 25.0%, 40.6% and 53.1% of patients at the final follow-up, respectively. At baseline 9.1%, 0% and 9.1% of patients had bilateral drusen ooze, iRORA and cRORA, respectively. By the final follow-up, drusen collapse occurred in 46.9% and 18.8% patients in unilateral and bilateral eyes, respectively.For bilateral cases, the mean interval of time between emergence inthe two eyes for drusen ooze, drusen collapse, iRORA, and cRORA was 5 ± 1.4 years, 2.2 ± 2.2 years, 3.5 ± 0.7 and 1.7 ± 0.6 years, respectively. CONCLUSIONS: Late-stage OCT biomarkers are seen bilaterally at 21.9% at baseline and at 56.3% at 5.8 years follow-up. Once present in one eye, cRORA had the shortest mean interval before appearance in the other eye.

Multimodal Imaging Based Predictors for the Development of Choroidal Neovascularization in Patients with Central Serous Chorioretinopathy.

This study evaluated predictors for choroidal neovascularization (CNV) associated with central serous chorioretinopathy (CSCR) based on multimodal imaging. A retrospective multicenter chart review was conducted on 134 eyes of 132 consecutive patients with CSCR. Eyes were classified as per the multimodal imaging-based classification of CSCR at baseline into simple/complex CSCR and primary episode/recurrent/resolved CSCR. Baseline characteristics of CNV and predictors were evaluated with ANOVA. In 134 eyes with CSCR, 32.8% had CNV (n = 44) with 72.7% having complex CSCR (n = 32), 22.7% having simple (n = 10) and 4.5% having atypical (n = 2). Primary CSCR with CNV were older (58 vs. 47, p = 0.00003), with worse visual acuity (0.56 vs. 0.75, p = 0.01) and of longer duration (median 7 vs. 1, p = 0.0002) than those without CNV. Similarly, recurrent CSCR with CNV were older (61 vs. 52, p = 0.004) than those without CNV. Patients with complex CSCR were 2.72 times more likely to have CNV than patients with simple CSCR. In conclusion, CNV associated with CSCR was more likely in complex CSCR and older age of presentation. Both primary and recurrent CSCR are implicated in CNV development. Patients with complex CSCR were 2.72 times more likely to have CNV than patients with simple CSCR. Multimodal imaging-based classification of CSCR supports detailed analysis of associated CNV.

Pathomechanisms in central serous chorioretinopathy: A recent update.

BACKGROUND: Central serous chorioretinopathy (CSCR) is a potentially blinding choroidal disease. Despite decades of research, the pathological mechanisms of CSCR are still poorly understood. In recent years, there has been a strong emphasis on choroidal dysfunction as a primary cause of CSCR. MAIN BODY: The concept of the pachychoroid disease spectrum and pachychoroid-driven processes are central to current theories regarding the pathophysiological underpinnings of CSCR. Choroidal hyperpermeability and subsequent leakage of fluid seen in CSCR may be due to several causes. Among them are venous congestion, inflammation, mineralocorticoid receptor activation, systemic factors including hemodynamic changes, obstructive sleep apnea, phosphodiesterase inhibitor use, pregnancy, and genetic predispositions. Congestion of vortex veins that drain blood from the choroid may contribute to the dilation of Haller vessels and cause fluid leakage. Vortex veins exit the eye through the sclera; thus, increased scleral thickness has been proposed to be a factor in venous congestion. Asymmetric vortex vein drainage may similarly result in congestion of the local venous system. Vortex vein anastomoses may overload the venous system and form secondary to venous congestion. Recent studies suggest inflammation and mineralocorticoid activation may factor into the development of CSCR, though more research in these areas is called for. Systemic conditions and genetics may predispose individuals to develop CSCR. CONCLUSIONS: By striving to understand the molecular and physiological mechanisms of this disease, we can better diagnose and treat CSCR to improve outcomes for patients.

Pigment epithelial detachment composition indices (PEDCI) in neovascular age-related macular degeneration.

We provide an automated analysis of the pigment epithelial detachments (PEDs) in neovascular age-related macular degeneration (nAMD) and estimate areas of serous, neovascular, and fibrous tissues within PEDs. A retrospective analysis of high-definition spectral-domain OCT B-scans from 43 eyes of 37 patients with nAMD with presence of fibrovascular PED was done. PEDs were manually segmented and then filtered using 2D kernels to classify pixels within the PED as serous, neovascular, or fibrous. A set of PED composition indices were calculated on a per-image basis using relative PED area of serous (PEDCI-S), neovascular (PEDCI-N), and fibrous (PEDCI-F) tissue. Accuracy of segmentation and classification within the PED were graded in masked fashion. Mean overall intra-observer repeatability and inter-observer reproducibility were 0.86 ± 0.07 and 0.86 ± 0.03 respectively using intraclass correlations. The mean graded scores were 96.99 ± 8.18, 92.12 ± 7.97, 91.48 ± 8.93, and 92.29 ± 8.97 for segmentation, serous, neovascular, and fibrous respectively. Mean (range) PEDCI-S, PEDCI-N, and PEDCI-F were 0.253 (0-0.952), 0.554 (0-1), and 0.193 (0-0.693). A kernel-based image processing approach demonstrates potential for approximating PED composition. Evaluating follow up changes during nAMD treatment with respect to PEDCI would be useful for further clinical applications.

Imaging characteristics of bilateral CSCR cases:12 months follow up.

PURPOSE: To report the disease pattern, progression and imaging characteristics in eyes with bilateral central serous chorioretinopathy (CSCR). METHODS: This was a retrospective case review of bilateral CSCR patients with active disease in at least one eye. Multimodal imaging including fundus photography, fundus autofluorescence, optical coherence tomography (OCT), fluorescein and indocyanine angiography (FA/ICGA) was done at baseline and follow-up visits. Disease classification was done using recently described classification criteria. The degree of asymmetry in the disease distribution pattern at baseline and disease progression during follow-up visit with a minimum duration of 12 months was studied. RESULTS: Among 103 CSCR patients, 36 patients (34.95%) with mean age of 53.6 ± 10.5 years had bilateral CSCR at baseline. Five patients (13.9%) had asymmetrical disease i.e. simple in one eye and complex in fellow eye. The remaining 31 patients had symmetric disease (simple, 2; complex 29). Mean duration of follow up was 17.58 ± 13.84 months. There was no significant difference between both eye parameters at last follow up (best corrected visual acuity, BCVA; central macular thickness, CMT; and subfoveal choroidal thickness, SFCT) (all p > 0.05). At last follow up, 22 eyes (2 simple and 20 complex) remained active whereas none of the eyes converted from simple to complex CSCR. CONCLUSION: Bilateral disease was more commonly seen with complex CSCR in contrast to simple CSCR. Moreover, disease distribution in complex CSCR had symmetric pattern if bilateral disease was present. None of the simple CSCR eyes converted to complex type.

Brachytherapy for Central Serous Chorioretinopathy.

Brachytherapy is widely used for the treatment of choroidal melanoma and has recently been explored for the treatment of wet age-related macular degeneration. We propose the use of low dose radiation via episcleral brachytherapy in refractory cases of central serous chorioretinopathy (CSCR). The pathogenesis of CSCR involves dilatation and hyperpermeability of large choroidal vessels. Low dose radiation can induce intimal proliferation in large choroidal vessels and decrease their hyperpermeability. Concerns about the use of brachytherapy in CSCR include damage to the choriocapillaris or the retinal vessels. This can be addressed with the use of a specialized device through which a very precise and appropriate dose can be delivered. The dose of the radiation delivered decreases exponentially at a depth of approximately 0.5-1.5 mm from the devise-sclera interface. Considering an increased choroidal thickness in cases of CSCR, delivery of a safe dose can be assured.

Regression patterns of central serous chorioretinopathy using en face optical coherence tomography.

PURPOSE: To study the regression patterns of subretinal fluid (SRF) in central serous chorioretinopathy (CSCR) on sequential en face optical coherence tomography (OCT) and its relationship to leak locations. METHODS: Retrospective study on patients with acute CSCR. Inclusion criteria were (i) availability of data, sequential OCT and OCT angiography (B scan and en face OCT) every 2 weeks until resolution of SRF or 6 months, whichever is earlier; (ii) single active leak. Exclusion criteria were (i) presence of macular neovascularization or atypical CSCR, (ii) diffuse pigment epitheliopathy, (iii) multiple leaks. Serial en face OCT scans were evaluated and the area of SRF was measured using ImageJ software. Correlation coefficient was calculated for the regression rate of SRF area and central retinal thickness (CRT) over the first month of follow-up and the time of complete SRF resolution. RESULTS: Out of the 25 eyes, 20 eyes demonstrated a centripetal regression, and 5 eyes demonstrated a centrifugal regression. In eyes with a leakage point <1000µ from the fovea, 86% resolved in a centripetal fashion, and in eyes with leak site ≥1000µ away from fovea, 70% eyes resolved centripetally. There was a correlation (r=-0.47, p=0.018) of the rate regression of SRF area during the first month and timing of resolution. In contrast, this correlation was absent (r=-0.16, p=0.44) for CRT regression. CONCLUSION: Our en face-based analysis of sequential OCTs of regressing CSCR demonstrated a tendency for the subfoveal SRF to resolve towards the end or a centripetal pattern of regression. Prediction of resolution of SRF at 1 month is better with en face area of SRF in comparison to CRT.

Influence of fellow eye on the diagnosis and classification of central serous chorioretinopathy.

PURPOSE: To assess the influence of fellow eye information on diagnosis and classification of central serous chorioretinopathy (CSCR) using multimodal imaging-based classification. METHODS: This was a retrospective, observational study including patients with CSCR with unilateral or bilateral involvement. Multimodal images of both eyes of each patient were compiled and presented to two masked retina specialists subdivided into three groups: (1) both eye data, (2) right eye data and (3) left eye data. The masked observers graded the CSCR as per the new CSCR classification into simple and complex CSCR in three different scenarios as subdivided above. Interobserver and intraobserver agreement was assessed using Cohen's kappa (95% confidence intervals). RESULTS: A total of 206 eyes of 103 patients with unilateral or bilateral CSCR were graded. We found a "strong" intraobserver and interobserver agreement when one eye versus both eye data was provided in terms of "simple CSCR" or "complex CSCR" (kappa value = 0.77 and 0.87, p < 0.001, and kappa value = 0.85 and 0.76, p < 0.001, respectively). Forty-three eyes (10.55%) showed discrepancy in classification between observers for individual eyes, whereas only 13 eyes (6.53%) showed discrepancy between observers when both eye data was provided. CONCLUSION: We conclude that fellow eye information was helpful in solving diagnostic dilemmas and reached 85% consensus in the diagnosis of CSCR between the observers. We found that information of fellow eyes led to a discrepancy only in 6.53% cases with 2.42% cases that had a controversial diagnosis of CSCR. Multimodal imaging-based CSCR classification provides objective approach to diagnose and classify CSCR.

Optical coherence tomography predictors of progression of non-exudative age-related macular degeneration to advanced atrophic and exudative disease.

PURPOSE: To study the natural history of optical coherence tomography (OCT) imaging-based findings seen in non-exudative age-related macular degeneration (neAMD) and model their relative likelihood in predicting development of incomplete retinal pigment epithelium and outer retinal atrophy (iRORA), complete retinal pigment epithelium and outer retinal atrophy (cRORA), and neovascular AMD (nAMD). METHODS: Retrospective chart review was performed at two academic practices. Patients diagnosed with neAMD for whom yearly OCT scans were obtained for at least 4 consecutive years were included. Baseline demographic, visual acuity, AREDS staging, and OCT data were collected. OCTs were assessed for the presence or absence of eleven features previously individually associated with progression of neAMD, both at baseline, and on all subsequent follow-up scans. Likewise, charts were reviewed to assess visual acuity and staging of NEAMD at all follow-up visits. A multivariate regression analysis was constructed to determine predictors of iRORA, cRORA, and nAMD. RESULTS: A total of 107 eyes of 88 patients were evaluated. Follow-up included yearly OCTs obtained over at least 4 consecutive years follow-up (range: 50-94 months). During the follow-up period, 17 eyes progressed to iRORA while 25 progressed to cRORA and 16 underwent conversion to nAMD. Predictors of conversion to iRORA and cRORA included integrity of the external limiting membrane (p = 0.02), the ellipsoid zone (p = 0.01), and the cone outer segment line (p = 0.003) and the presence of intraretinal hyporeflective spaces (p = 0.009), drusen ooze (p = 0.05), and drusen collapse (p = 0.001). OCT features predictive of conversion to nAMD included outer nuclear layer (ONL) loss (p = 0.01), presence of intraretinal (p = 0.001) and subretinal (p = 0.005) hyporeflective spaces, and drusen collapse (p = 0.003). CONCLUSION: Of these multiple factors predictive of progression of neAMD, the OCT feature most strongly correlated to progression to iRORA/cRORA was drusen collapse, and the feature most predictive of conversion to nAMD was the presence of intraretinal hyporeflective spaces.

Visual acuity correlates with multimodal imaging-based categories of central serous chorioretinopathy.

OBJECTIVE: To evaluate visual acuity (VA) and factors influencing VA using new multimodal imaging-based classification of central serous chorioretinopathy (CSCR). METHODS: Retrospective, observational and cross-sectional study on 229 naïve eyes diagnosed as CSCR with available baseline data and multimodal imaging. Each case was classified into (i) simple/complex/atypical; (ii) primary/recurrent/resolved; (iii) persistent or not; (iv) outer retinal atrophy(ORA) present/absent; (v) foveal involvement present/absent; and (vi) macular neovascularization(MNV) present/absent. Best corrected visual acuity (BCVA) was correlated to the classification as well as every parameter of the classification. RESULTS: Median BCVA was 0.18 logMAR [95% Confidence Interval (CI)0.16-0.18] with median duration of complaints of one month (95% CI,6.14-13.0 months). Age of the patient (r = -0.24, p = 0.002) and duration of the disease (r = -0.32, p < 0.001) correlated significantly with BCVA. Logistic regression model showed that older age [odds ratio (OR) = 0.96, p = 0.05], female gender (OR = 2.45, p = 0.046), presence of ORA(OR = 0.34, p = 0.012),and foveal involvement(OR = 0.18, p = 0.007) were statistically significantly associated with poorer BCVA. Eyes classified as complex, persistent CSCR, with ORA or foveal involvement demonstrated lower BCVA compared to those with simple, non-persistent CSCR, without ORA or without foveal involvement (p < 0.05). Eyes with complex CSCR (p < 0.001), atypical CSCR(p = 0.025), persistent subretinal fluid (SRF) (p = 0.001) and those with ORA (p < 0.001) demonstrated a trend towards severe visual loss. Prevalence of persistent SRF, recurrent episodes and ORA was significantly higher among eyes with complex CSCR (p < 0.001) while there was no difference in prevalence of resolved cases (p = 0.07), foveal involvement (p = 0.28) and MNV (p = 0.45) between simple and complex cases. CONCLUSION: There is a strong correlation between VA and foveal involvement and ORA using the new classification. Thus, the objective parameters of the classification can be incorporated in establishing the treatment guidelines for CSCR.

Intraretinal, sub-retinal, and sub-retinal pigmented epithelium fluid in non-exudative age-related macular degeneration: follow-up with OCT imaging.

BACKGROUND/OBJECTIVES: To evaluate the presence and evolution of fluid in non-exudative age-related macular degeneration (AMD) through serial OCT. SUBJECTS/METHODS: A retrospective analysis of eyes with non-exudative AMD with a minimum of 4 year follow-up was done. Parameters including intraretinal fluid (IRF), subretinal fluid (SRF), and sub-retinal pigment epithelium (RPE) fluid (SRPEF); subfoveal choroidal thickness (SFCT) and type of drusen were evaluated using optical coherence tomography (OCT) scans at baseline and follow up visits. RESULTS: Seventy-two eyes (in 63 patients) were followed up for an average of 5.83 ± 2.17 years. A total of 26/72 (36%) and 29/65 (52%) of the non-exudative eyes had fluid during baseline and the last visit. Seven eyes (10%) out of 72 eyes converted into exudative AMD or neo-vascular AMD (nAMD) during the study period. SRPEF at baseline was most common fluid location for non-exudative eyes that eventually converted to nAMD. CONCLUSION: Non-exudative fluid including IRF, SRF, and SRPEF is seen in patients with non-exudative AMD with increasing incidence during long term follow-up.

Sildenafil in ophthalmology: An update.

Sildenafil citrate, a selective oral phosphodiesterase 5 inhibitor, is a widely used drug for erectile dysfunction that acts by elevating cGMP levels and causing smooth muscle relaxation. It also has 10% activity against PDE6, a key enzyme in phototransduction cascade in the retina. Recent ocular imaging developments have further revealed the influence of sildenafil on ocular hemodynamics, particularly choroidal perfusion. Choroidal thickness is increased, and choroidal perfusion is also enhanced by autoregulatory mechanisms that are further dependent on age and microvascular abnormalities. Studies demonstrating high intraocular pressure via a "parallel pathway" from increased choroidal volume and blood flow to the ciliary body have challenged previous concepts. Another new observation is the effect of sildenafil on bipolar cells and cyclic-nucleotide gated channels. We discuss potential deleterious effects (central serous chorioretinopathy, glaucoma, ischemic optic neuropathy, and risks to recessive carriers of retinitis pigmentosa), potential beneficial effects (ameliorate choroidal ischemia, prevent thickening of Bruch membrane, and promote recovery of the ellipsoid zone) in macular degeneration, as well as potential drug interactions of sildenafil.

Retinal toxicities of systemic anticancer drugs.

Newer anticancer drugs have revolutionized cancer treatment in the last decade, but conventional chemotherapy still occupies a central position in many cancers, with combination therapy and newer methods of delivery increasing their efficacy while minimizing toxicities. We discuss the retinal toxicities of anticancer drugs with an emphasis on the mechanism of toxicity. Uveitis is seen with the use of v-raf murine sarcoma viral oncogene homolog B editing anticancer inhibitors as well as immunotherapy. Most of the cases are mild with only anterior uveitis, but severe cases of posterior uveitis, panuveitis, and Vogt-Koyanagi-Harada-like disease may also occur. In the retina, a transient neurosensory detachment is observed in almost all patients on mitogen-activated protein kinase kinase (MEK) inhibitors. Microvasculopathy is often seen with interferon α, but vascular occlusion is a more serious toxicity caused by interferon α and MEK inhibitors. Crystalline retinopathy with or without macular edema may occur with tamoxifen; however, even asymptomatic patients may develop cavitatory spaces seen on optical coherence tomography. A unique macular edema with angiographic silence is characteristic of taxanes. Delayed dark adaptation has been observed with fenretinide. Interestingly, this drug is finding potential application in Stargardt disease and age-related macular degeneration.