Automated machine learning-based classification of proliferative and non-proliferative diabetic retinopathy using optical coherence tomography angiography vascular density maps.

PURPOSE: The study aims to classify the eyes with proliferative diabetic retinopathy (PDR) and non-proliferative diabetic retinopathy (NPDR) based on the optical coherence tomography angiography (OCTA) vascular density maps using a supervised machine learning algorithm. METHODS: OCTA vascular density maps (at superficial capillary plexus (SCP), deep capillary plexus (DCP), and total retina (R) levels) of 148 eyes from 78 patients with diabetic retinopathy (45 PDR and 103 NPDR) was used to classify the images to NPDR and PDR groups based on a supervised machine learning algorithm known as the support vector machine (SVM) classifier optimized by a genetic evolutionary algorithm. RESULTS: The implemented algorithm in three different models reached up to 85% accuracy in classifying PDR and NPDR in all three levels of vascular density maps. The deep retinal layer vascular density map demonstrated the best performance with a 90% accuracy in discriminating between PDR and NPDR. CONCLUSIONS: The current study on a limited number of patients with diabetic retinopathy demonstrated that a supervised machine learning-based method known as SVM can be used to differentiate PDR and NPDR patients using OCTA vascular density maps.

Presumed retinal lead poisoning: a case report.

PURPOSE: To describe a case of presumed retinal lead poisoning. METHODS: Clinical examination, optical coherence tomography, fundus autofluorescence, fluorescein angiography, and electroretinography were used to study a 42-year-old male with the complaint of bilateral reduced vision following systemic lead poisoning. RESULTS: The fundus examination showed venous tortuosity, as well as macular atrophy, and pigmentary changes in his both eyes. Optical coherence tomography revealed retinal thinning, outer retinal and retinal pigment epithelium atrophy, as well as foveal schitic changes. Blue autofluorescence showed moderately hypoautofluorescence in peripapillary area of both eyes. Fluorescein angiogram showed a leopard-like pattern of hypo- and hyperfluorescence in the posterior pole. Electroretinogram showed a moderate reduction in photopic and scotopic responses. CONCLUSIONS: The most probable diagnosis of this case is early onset retinal lead poisoning.

Post-intravitreal injection endophthalmitis pattern during the COVID-19 pandemic with implementation of patients' masking.

PURPOSE: To evaluate the role of patient facial masks on the occurrence of post-intravitreal injection (IVI) endophthalmitis in a real-word setting. METHODS: In this retrospective cohort, patients receiving IVIs between 20 February 2019 and 20 February 2021; a 12-month period before the official beginning of COVID-19 epidemic in Iran and a 12-month period thereafter were included. In the pre-COVID era, patients underwent IVI without a facial mask while in the COVID era patients wore an untaped facial mask. Physicians and staff had facial mask in both periods. IVIs were administered in a dedicated operating room without a strict no talk-policy. The main outcome measure was the rate of post-IVI endophthalmitis. RESULTS: A total number of 53,927 injections was performed during the study period: 34,277 in pre-COVID and 19,650 in COVID periods; with a 42.7% decrease in the number of injections. Endophthalmitis occurred in 7 eyes (0.020%) in pre-COVID and 7 eyes (0.036%) in COVID era (p = 0.40). In multivariate analysis, after adjustment for intercorrelations between the eyes and multiple injections in one patient, there was no statistically significant association between wearing facial masks by the patients and risk of endophthalmitis (relative risk = 1.47, 95% confidence interval of 0.97-2.22; p = 0.071). CONCLUSION: Patients' facial masking is not associated with an increased risk of post-injection endophthalmitis.

Alterations in choroidal vascular parameters following panretinal photocoagulation using enhanced-depth imaging optical coherence tomography in diabetic retinopathy.

PURPOSE: To investigate the alteration of choroid in patients with very severe non-proliferative diabetic retinopathy (NPDR) or early proliferative diabetic retinopathy (PDR) following panretinal photocoagulation (PRP). METHODS: Thirty-nine eyes of 21 patients with very severe non-proliferative diabetic retinopathy (NPDR) (19 eyes) and early proliferative diabetic retinopathy (PDR) (20 eyes) were recruited. Enhanced-depth imaging optical coherence tomography at baseline, 1, and 6 months after PRP was employed to measure choroidal parameters including total choroidal area (TCA) and choroidal vascular index (CVI). RESULTS: In eyes with very severe NPDR, subfoveal TCA decreased non-significantly at month 1, which increased significantly at month 6 (539 ± 131µm2, 502 ± 134µm2, and 598 ± 168µm2 at baseline and months 1 and 6, respectively; P = 0.003). Subfoveal CVI increased at month 1 and then decreased at month 6 (68.25 ± 3.05, 69.74 ± 3.62, and 67.84 ± 1.77 at baseline and months 1 and 6, respectively; P < 0.001). A reverse pattern occurred in eyes with early PDR, a non-significant increase in TCA at month 1 followed by a decrease at month 6 (497 ± 95µm2, 514 ± 133µm2, and 425 ± 95µm2 at baseline and months 1 and 6, respectively; P = 0.011). CVI decreased at month 1 and remained relatively stable at month 6 (69.34 ± 3.11, 68.33 ± 3.41, and 68.50 ± 5.04 at baseline, and months 1 and 6, respectively; P = 0.023). Alteration of choroidal thickness was not statistically significant in both groups. CONCLUSION: Eyes with very severe NPDR and early PDR exhibit a reverse pattern regarding choroidal indices after PRP.

Intravitreal bevacizumab to treat retinopathy of prematurity in 865 eyes: a study to determine predictors of primary treatment failure and recurrence.

PURPOSE: This study aimed to evaluate the rate and risk factors for primary failure and recurrence after intravitreal anti-VEGF injection in retinopathy of prematurity (ROP). METHODS: This retrospective study was performed on 865 eyes from 441 patients with retinopathy of prematurity receiving intravitreal bevacizumab from 2012 to 2019. Medical records of patients were evaluated. RESULTS: Mean gestational age (GA) and birth weight of patients were 28 ± 2 weeks and 1121 ± 312 g, respectively. Thirty-five eyes (4.04%) had a primary failure, including 18 eyes from 187 eyes in zone 1 (9.6%) and 17 eyes from 678 eyes in zone 2 (2.5%). The mean time of retreatment was 16.64 ± 13.68 days in eyes without regression ROP. The remaining 830 eyes (95.95%) were included in recurrence analysis. The recurrence occurred in 33 eyes (3.97%) of them in 20 patients, with the meantime of 77.52 days after the first treatment (IVB). The presence of plus disease, history of oxygen therapy or phototherapy, and GA less than 32 were associated with significantly increased prevalence of treatment failure. The risk factors predicting recurrence are lower birth weight, zone 1 pretreatment, history of intubation, anemia, and sepsis. CONCLUSION: Intravitreal anti-VEGF is a successful treatment for ROP with a low rate of primary failure and recurrence. Awareness of risk factors for treatment failure and recurrence may help clinicians to schedule more vigilant approach in susceptible cases.

SPOAN syndrome: a novel mutation and new ocular findings; a case report.

BACKGROUND: To report a novel mutation and new clinical findings in a case with SPOAN syndrome (spastic paraplegia, optic atrophy, neuropathy). CASE PRESENTATION: Clinical examination, genetic testing and electroretinography were used to study a 2-year-old child who was referred to our clinic with no visual attention and documented SPOAN syndrome. Fundoscopy revealed optic atrophy, diffuse retinal pigment mottling, severe vascular attenuation, and completely non-vascularized peripheral retina in both eyes. Full-field electroretinogram (ERG) revealed flat responses. CONCLUSIONS: Severe retinopathy and flat full-field ERG responses can occur in SPOAN syndrome.

Retinal displacement following pars plana vitrectomy with silicone oil tamponade for rhegmatogenous retinal detachment.

PURPOSE: To evaluate the frequency of retinal displacement after pars plana vitrectomy (PPV) using silicone oil tamponade in patients with rhegmatogenous retinal detachment (RRD). METHODS: Patients with fresh RRD were enrolled in this prospective interventional case series. A standard 3-port PPV with silicone oil tamponade was performed in all cases. A complete ocular examination, optical coherence tomography and fundus autofluorescence (FAF) imaging were performed at 1 and 3 months follow-up. Orthoptic examinations including synoptophore and light on-off tests were also performed at 3 months. RESULTS: Twenty-three eyes from 23 patients with mean age of 56.6 ± 11 (range: 38-82) years were included. All patients were pseudophakic. Downward retinal displacement was found in 2 eyes (8.7%) showing hyperautofluorescent lines parallel to retinal vessels in FAF image. The patients with retinal displacement did not complain of metamorphopsia and did not show abnormality in orthoptic tests. CONCLUSION: Unintentional retinal shift following PPV with silicone oil tamponade for RRD is uncommon and might have little clinical significance.

Central serous chorioretinopathy and achromatopsia: a case report.

PURPOSE: To describe a patient with combined central serous chorioretinopathy and achromatopsia. METHODS: Clinical examination, enhanced depth imaging- optical coherence tomography, fundus autofluorescence, fluorescein angiography and electroretinography were used to study a 33-year-old female presented with the complaint of poor vision since childhood in both eyes, which worsened in the left eye (LE) recently. RESULTS: In slit-lamp examination, there was a macular elevation in the LE and macular pigmentary change as well as optic disk pallor in both eyes. Enhanced depth imaging optical coherence tomography revealed central inner/outer segment (IS/OS) disruptions, subretinal fluid and thick choroid. Accessory tests included the full-field ERG with severe reduced photopic response (with relatively normal scotopic responses) and fluorescein angiography (FA), which found distinct leakage points in OD and barely visible hyperfluorescent spots in OS. Based on the history of nystagmus, lifelong stable poor vision, loss of foveal cone thickness with IS/OS disruption and severe reduced photopic response with relatively normal scotopic responses, we determined that the diagnosis was most consistent with achromatopsia (ACHM). On the other hand, OCT and FA findings show the simultaneous occurrence of pachychoroid-related central serous chorioretinopathy in this patient. CONCLUSION: This case highlights a case of CSC and ACHM.

Multifocal electroretinogram in diabetic macular edema and its correlation with different optical coherence tomography features.

PURPOSE: To evaluate multifocal electroretinogram (mfERG) parameters in eyes with diabetic macular edema (DME) and its correlation with vision and optical coherence tomography (OCT) features. METHODS: Fifty-four eyes of 27 subjects with DME due to nonproliferative diabetic retinopathy were evaluated. MfERG responses were measured in three concentric rings. Macular thickness was measured by OCT in each segment of the three concentric rings, and mfERG rings were superimposed on the macular thickness map. The correlation between macular thickness in specific points of the thickness map and changes of the mfERG parameters in the corresponding points of the mfERG field map was evaluated and the relationship between the OCT and mfERG changes and changes of best-corrected visual acuity (BCVA) was investigated. The central foveal B-scans of SD-OCT were used to evaluate any correlation between the external limiting membrane (ELM) status, ellipsoid zone (EZ) status, presence of cysts or disorganization of retinal inner layers (DRIL), and mfERG parameters at the central corresponding area. RESULTS: The mean of BCVA was 0.5 ± 0.3 in logMAR, and the central macular thickness was 392.6 ± 123.4 microns. The central ring P1 and N2 amplitudes had a significant correlation with BCVA in univariate and multivariate analyses (P = 0.001 for both, r = - 0.346 and r = - 0.646, respectively). There was a significant correlation between retinal thickness and the N1 amplitude in the central ring (P = 0.02, r = - 0.343). Outer retinal layer disruption (ELM and EZ) correlated with prolonged P1 implicit time at the corresponding location (P = 0.005, r = 0.068). The presence of the DRIL was associated with reduced P1 and N2 amplitudes (P = 0.037, r = - 0.284 and P = 0.019, r = - 0.562, respectively). A significant correlation was also found between the presence of cysts and a lower central P1 amplitude (P = 0.033, r = - 0.376). CONCLUSION: In diabetic patients, discrete changes of some parameters in the central ring of the mfERG field map (e.g., P1 and N2 amplitudes) have a significant correlation with both structural OCT abnormalities in the corresponding points of the thickness map (like DRIL, intraretinal cyst and ELM/EZ disruption) and BCVA. Predictive models such as those described in this report may make it possible to identify the relationship between specific anatomical and functional characteristics in diabetic retinopathy.

Novel findings in enhanced S-cone syndrome: a case with macular retinal neovascularization and severe retinal vasculitis.

PURPOSE: To describe a novel association of enhanced S-cone syndrome (ESCS) with macular retinal neovascularization and severe retinal vasculitis. METHODS: Clinical examination, spectral domain optical coherence tomography, fluorescein angiography, fundus autofluorescence, infrared reflectance and electroretinography were used to study a 25-year-old male with a history of night blindness from early childhood and recent accelerated visual loss in right eye. RESULTS: Pigmented lesions were observed along the arcades without peripheral retinal involvement. Intraretinal cystoid spaces, retinal neovascularization of posterior pole and severe peripheral and posterior retinal vasculitis were found on clinical examination and multimodal imaging. Based on characteristic clinical and electroretinographic findings, a diagnosis of ESCS was made. CONCLUSION: This case highlights novel associations of retinal neovascularization and vasculitis with ESCS.

Pushed monocanalicular intubation versus probing for the treatment of simple and incomplete complex types of congenital nasolacrimal duct obstruction in children older than 18 months old.

This article compares the success rate of pushed monocanalicular intubation (Masterka) versus probing for the treatment of congenital nasolacrimal duct obstruction (CNLDO) in children older than 18 months. In a non-random comparative study, 90 eyes with CNLDO underwent either Masterka (45 eyes) or probing (45 eyes). All procedures were performed by one oculoplastic surgeon. The tubes were removed 2 months after the operation. Complete resolution was defined as complete absence of clinical signs and symptoms of CNLDO at 6 months after the procedure. The mean age at the time of treatment was 28 ± 18.2 months for Masterka and 26.7 ± 18.6 months for probing group. Treatment success was achieved in 33 of 45 eyes (73.3%) in the Masterka group compared with 22 of 45 eyes (48.9%) in the probing group. The difference between the two groups was statistically significant (p = 0.017). For the treatment of CNLDO, Masterka might be more effective than probing in children older than 18 months.

COMPARISON OF ANTERIOR SEGMENT OPTICAL COHERENCE TOMOGRAPHY PARAMETERS BETWEEN CENTRAL RETINAL VEIN OCCLUSION AND NORMAL EYES: Is Primary Angle Closure a Risk Factor for Central Retinal Vein Occlusion?

PURPOSE: To compare anterior segment parameters in patients with central retinal vein occlusion (CRVO) with normal control subjects by anterior segment optical coherence tomography (AS-OCT). METHODS: In this coss-sectional case-control study, 42 eyes from 21 patients with unilateral CRVO and 21 eyes from 21 age- and sex-matched healthy control subjects were recruited. Study eyes were divided into three groups: involved eyes of CRVO patients (CRVO eyes), fellow eyes of CRVO patients (fellow eyes), and control eyes. Complete ocular examination and AS-OCT were performed for each eye. The AS-OCT parameters (anterior chamber depth, scleral spur angle, angle opening distance [AOD] at 500 and 750 µm from scleral spur [AOD500 and 750] and trabecular-iris space area [TISA] at 500 and 750 µm from scleral spur [TISA500 and 750]) and the rate of narrow angles (based on gonioscopy) in CRVO and fellow eyes were compared with control eyes. RESULTS: The mean (SD) age of the patients and the control group were 60.09 (9.43) and 59.52 (6.66), respectively. The mean intraocular pressure in both eyes of the patients was significantly higher than the control eyes (P < 0.05). All AS-OCT parameters were significantly different among the three groups (P < 0.05). Comparing with the control eyes, CRVO eyes had shallower anterior chamber depth (2.53 vs. 2.85 mm; P = 0.002) and narrower AS-OCT angle parameters (scleral spur angle, AOD500 and 750, TISA500 and 750). Fellow eyes had also shallower anterior chamber depth (2.56 vs. 2.85 mm; P = 0.005) than control eyes and smaller scleral spur angle, AOD500 and AOD750. Five CRVO patients (23.8%) were diagnosed with narrow angles in both eyes based on gonioscopy, whereas no eye in the control group had narrow angles (P = 0.05). CONCLUSION: Imaging with AS-OCT showed that CRVO patients had shallower anterior chamber depth and narrower angle parameters in both eyes in comparison with control eyes. Furthermore, CRVO patients had higher rates of narrow angles on gonioscopic examination.

Femtosecond laser-assisted MyoRing implantation in postoperative LASIK ectasia.

PURPOSE: To evaluate the effect of MyoRing implantations (DIOPTEX GmbH, Linz, Austria) in patients with ectasia after LASIK. METHODS: MyoRing implantation was performed in 15 eyes of 14 patients with ectasia after LASIK using a femtosecond laser. Uncorrected and corrected distance visual acuity, refraction, keratometry, central corneal thickness, corneal biomechanical profile, and corneal aberrometry were evaluated preoperatively and at 1, 3, and 6 months, and 1 year postoperatively. RESULTS: Uncorrected distance visual acuity (1.02 ± 0.48 to 0.30 ± 0.18 logMAR), maximum keratometry (50.14 ± 1.82 to 43.80 ± 1.21 diopters), and sphere (-4.4 ± 4.8 to +1.50 ± 0.61 diopters) were significantly improved from preoperative values at 1 month after surgery with no significant change afterward. Corrected distance visual acuity did not improve significantly 1 month after implantation, but between the 1- and 3-month follow-up visits, a significant improvement (0.30 ± 0.1 to 0.17 ± 0.13 logMAR) was observed without any additional improvement thereafter. A nearly significant (P = .05) increase in central corneal thickness (439.4 ± 19 to 452.2 ± 20 µm) was observed during the 1-month postoperative period. Primary coma, higher-order aberrations, and trefoil showed an insignificant decrease 1 month after surgery and afterward. Spherical aberration significantly increased between the preoperative visit and the first postoperative visit. Corneal hysteresis and corneal resistance factor showed no significant change between visits. CONCLUSIONS: MyoRing is a safe and effective method in patients with ectasia after LASIK. It can improve corrected distance visual acuity and reduce refractive error in these patients.

Choroidal measurements in decision making for retinopathy of prematurity: a decision tree analysis.

BACKGROUND: To compare the choroidal thickness and vascular profile of premature infants with ROP (retinopathy of prematurity) using a handheld SD-OCT device. METHODS: We performed horizontal SD-OCT scans through the fovea in 115 eyes of 66 premature infants. Premature infants included 2 groups [infants with ROP requiring treatment (as treatment group) vs. infants without ROP or with ROP not- requiring treatment (as no-treatment group)] Choroidal thicknesses (CT) were measured at 5 points, including the fovea, 250 µm, and 500 µm mm nasal and temporal to the fovea. The choroidal vascularity index (CVI) and choroidal stromal index (CSI) were also calculated. The classification and regression tree (CRT) algorithm was used to predict the need for treatment based on all OCT characteristics. RESULTS: Mean CT was higher in 500 µm nasal to the fovea compared to temporal CT (275.8 ± 64.8 and 257.1 ± 57.07, P value < 0.03). No statistically significant difference was found regarding CVI, corrected CVI, and temporal and nasal CT in the treatment group versus the no-treatment group. The foveal CT was significantly lower in ROP patients with the plus disease compared to not-plus ROP (P value = 0.03. ANOVA, Bonferroni posthoc test). CT was not significantly different between plus and pre-plus patients (P-value = 0.9, ANOVA, Bonferroni posthoc test). No significant relationship was found between the stage of ROP and choroidal thickness (P value > 0.05, GEE). The decision tree analysis showed that in infants with ROP, the most important predictor for the need for treatment is CSI. CONCLUSION: This study delineated the possible effectiveness of choroidal measurements as an additive to decision-making for ROP. We also demonstrated that choroidal involution is associated with the presence of plus disease, not with the stage of ROP. We demonstrated that choroidal measurements are very sensitive but not specific tools for assessing the need for treatment in ROP patients.

Hemicentral retinal vein occlusion in a patient with a history of coronavirus disease 2019 infection: a case report and review of the literature.

BACKGROUND: Considering the various manifestations of coronavirus disease 2019 and its imperative importance in terms of the right clinical approach and early management, we sought to present a hemicentral retinal vein occlusion case, with a history of heterozygosity of methylenetetrahydrofolate reductase (MTHFR) genes and potential for clotting complications as a late manifestation of coronavirus disease 2019, and provide a brief review of reported retinal vein occlusion cases in patients with coronavirus disease 2019. CASE PRESENTATION: A 35-year-old Iranian patient presented with a visual impairment in the left eye 4 months after recovering from coronavirus disease 2019. He reported a mild blurring of vision in the same eye a few days after admission due to coronavirus disease 2019. The ophthalmic evaluation was compatible with hemicentral retinal vein occlusion. Systemic and laboratory workups were negative except for borderline protein C activity, homocysteine levels, and heterozygosity of MTHFR genes. The patient was scheduled to receive three monthly intravitreal antivascular endothelial growth factor injections. CONCLUSION: We present a case of inferior hemicentral retinal vein occlusion case with an MTHFR mutation with sequential loss of vision 4 months after coronavirus disease 2019 to make clinicians aware of the possibility of late ocular coronavirus disease 2019 manifestations.

Evaluating the Efficacy and Safety of Aflibercept Biosimilar (P041) Compared with Originator Product in Patients with Neovascular Age-Related Macular Degeneration.

OBJECTIVE: To assess the noninferiority of biosimilar aflibercept (P041, CinnaGen) to the originator aflibercept (AFL, Regeneron) in terms of efficacy, safety, and immunogenicity. DESIGN: This was a phase Ш, 52-week, multicenter, randomized, double-masked, and active control trial involving eyes in a 1:1 ratio. SUBJECTS: Patients with active subfoveal choroidal neovascularization secondary to age-related macular degeneration randomized into the 2 groups of P041 and AFL. METHODS: Patients received an injection of aflibercept every 4 weeks for 3 doses, followed by administration every 8 weeks up to week 48. MAIN OUTCOME MEASURES: The primary outcome was the noninferiority analysis of eyes maintaining vision at week 52. Secondary outcomes included the changes in visual acuity and retinal thickness, safety evaluation, and immunogenicity during the study. RESULTS: In total, 168 eyes of 168 patients were included. At week 52, the proportion of patients maintaining vision was 94.44% in the P041 group compared with 94.52% in the AFL group. The 95% confidence interval (CI) for the difference of maintaining vision from baseline did not exceed the predefined noninferiority margin of 10% (difference, -0.0008; 95% CI, -0.074 to 0.074; P = 0.98). Secondary outcomes indicated similar results in both arms (all P > 0.05). Safety measured outcomes and immunogenicity were similar between the 2 study groups. CONCLUSIONS: Biosimilar aflibercept was noninferior to AFL in eyes with neovascular age-related macular degeneration. Other efficacy and safety findings also indicated the similarity of 2 products. FINANCIAL DISCLOSURES: Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Presumed veterinary niclosamide-induced retinal toxicity in a human: a case report.

BACKGROUND: To report the first case of bull's eye maculopathy associated with veterinary niclosamide. CASE PRESENTATION: A 27-year-old Iranian female presented with a history of reduced vision and photopsia since 3 years, after accidental ingestion of four boluses of veterinary niclosamide. Fundus examination showed atrophy in parafoveal retinal pigmentary epithelium, appearing as bilateral bull's-eye maculopathy. Optical coherence tomography revealed disruption of the parafoveal ellipsoid zone and outer retinal thinning, appearing as a flying saucer sign. Electroretinography displayed decreased scotopic and photopic amplitudes with normal waveform in both eyes. The causality score was 4, showing "possible" retinopathy due to niclosamide according to Naranjo's causality assessment algorithm. Based on clinical and ancillary findings, a diagnosis of niclosamide-induced maculopathy was made. CONCLUSION: Veterinary niclosamide is an anthelmintic drug that in higher doses could be detrimental to the human retina. Awareness about its side effects and appropriate drug labeling could prevent accidental toxicity.

Evaluation of Histopathologic Findings and Safety of Intravitreal Ketamine Administration on Vitreoretinal Tissue in Rat Model: A Pilot Study.

Purpose: To evaluate the safety and histological findings of intravitreal injection of ketamine in rats. Methods: Each rat received a total volume of 0.1 ml of ketamine 0.01 mol/L (5 rats as ketamine group) or a total of 0.1 ml of normal saline 0.9% (5 rats as control group) under general anesthesia in a sterile condition. A histology assessment was performed 1 month after the intravitreal injection. Results: Lens opacity, necrosis, and atrophy of retinal layers and optic disc were not seen in five specimens in the ketamine group and five in the normal saline group. There was no inflammation in the vitreous, retinal layers, choroid, optic disc, and optic nerve in both groups. Conclusion: Intravitreal injection of ketamine in a special dose has no obvious adverse effect on diverse intraocular tissue.

Tamoxifen retinopathy.

Tamoxifen (TAM) is a selective estrogen receptor modulator that is used in the treatment of breast cancer. As there are estrogen receptors in the retina, retinal pigment epithelium, and choroid, these tissues may also be affected by TAM. We describe the reported effects of TAM on the retina and choroid. Medical databases were searched using relevant keywords and the results were extracted and pooled. The incidence of retinal/choroidal toxicity ranged from 0.9% to 12%. There was a wide range for the time of exposure before the development of TAM retinopathy (3 weeks to 13 years). While functional measurements may be appropriate for assessment of TAM retinopathy, they have not been effective for screening patients. There is no generally accepted screening modality, but serial funduscopy and optical coherence tomography imaging seem to be the most reasonable approach for detecting early TAM-induced retinal toxicity.

Short term choroidal microvascular changes following photodynamic therapy in chronic central serous chorioretinopathy.

BACKGROUND: Central serous chorioretinopathy (CSC) is characterized by focal serous detachment of the retina, primarily affecting the macula. Photodynamic therapy (PDT) is the best choice for treatment of chronic and recurrent patients. In this study we aim to evaluate the early effects of the half dose protocol (3 mg/m2 verteporfine) of PDT laser treatment on the micro vasculature of choroid. METHODS: Among thirty-one patients (62 eyes), twenty eyes were in the control group and forty-two eyes received PDT laser treatment. Vision log MAR, CMT (central macular thickness), SRF (sub retinal fluid), BCT (baseline choroidal thickness), CVI (choroidal vascular index), and laser treated area were compared between two groups. RESULTS: Results show that no strong correlation was detected between the impact of laser treatment and resolution of SRF in the first week in the fovea. The mean best corrected visual acuity (BCVA) of the patients significantly increased from 20/63 at the beginning of the study, according to the Snellen chart, to 20/49 in the first week and 20/38 in the sixth week. PDT can significantly reduce SRF and CMT in 6 weeks compared to the control group. Although there was initially a small, non-statistically significant increase in choroidal thickness and CVI after 1 week, a dramatic decrease occurs after 6 weeks. Therefore, after 6 weeks of PDT laser, all the indicators such as SRF, CMT, choroidal thickness, and CVI significantly reduced. CONCLUSION: PDT laser can significantly reduce SRF and CMT at 1 and 6 weeks and choroidal thickness and CVI at 6 weeks in chronic CSC patients. Also, a larger laser treated area has no impact on the final outcome. Therefore, it seems that the mechanism of PDT in CSC disease is the recovery of choriocapillaris circulation.