A COVID-19-Related Retinopathy Case Report.

The recent outbreak of the severe acute respiratory syndrome coronavirus-2 has been declared a worldwide pandemic by the WHO. Within various multi-organ involvements, several ocular manifestations have been described. We report the case of a patient diagnosed with COVID-19 who presented with a progressive increase of bilateral cotton wool spots over a 1-week period, despite quick and complete recovery of systemic signs of the disease and no ocular symptoms. We followed the evolution of such lesions over a 3-month period. Here, we underline the importance of retinal screening even if no ocular symptom is reported. Furthermore, we demonstrate the essential role of fundus examination as a reflection of systemic vascular changes.

Retinal Manifestations in Patients with COVID-19: A Prospective Cohort Study.

The recent outbreak of the Coronavirus SARS-CoV-2 has been declared a worldwide pandemic. Within various multi-organ involvement, several ocular manifestations have been described, such as conjunctivitis and retinopathy. The prevalence and severity of retinal lesions and their relation to the severity of the systemic disease are unknown. We performed a prospective, observational study on 172 consecutively hospitalized patients with acute confirmed COVID-19 infection. All patients underwent screening widefield fundus photography at the time of hospital admission. Despite no ocular or vision-related symptoms, we found cotton wool spots (CWS) and/or hemorrhages in 19/172 patients (11%). Diabetes history, overweight, and elevated C-reactive protein were more frequently observed among patients with retinal abnormalities, while a history of systemic hypertension was more frequently observed among patients without retinal findings. At a 3-month follow-up visit, CWS had subsided in all patients.

Standardization of choroidal thickness measurements using enhanced depth imaging optical coherence tomography.

AIM: To describe and evaluate a standardized protocol for measuring the choroidal thickness (ChT) using enhanced depth imaging optical coherence tomography (EDI OCT). METHODS: Single 9 mm EDI OCT line scans across the fovea were used for this study. The protocol used in this study classified the EDI OCT images into four groups based on the appearance of the choroidal-scleral interface and suprachoroidal space. Two evaluation iterations of experiments were performed: first, the protocol was validated in a pilot study of 12 healthy eyes. Afterwards, the applicability of the protocol was tested in 82 eyes of patients with diabetes. Inter-observer and intra-observer agreements on image classifications were performed using Cohen's kappa coefficient (κ). Intraclass correlation coefficient (ICC) and Bland-Altman's methodology were used for the measurement of the ChT. RESULTS: There was a moderate (κ=0.42) and perfect (κ=1) inter- and intra-observer agreements on image classifications from healthy eyes images and substantial (κ=0.66) and almost perfect (κ=0.86) agreements from diabetic eyes images. The proposed protocol showed excellent inter- and intra-observer agreements for the ChT measurements on both, healthy eyes and diabetic eyes (ICC>0.90 in all image categories). The Bland-Altman plot showed a relatively large ChT measurement agreement in the scans that contained less visible choroidal outer boundary. CONCLUSIONS: A protocol to standardize ChT measurements in EDI OCT images has been developed; the results obtained using this protocol show that the technique is accurate and reliable for routine clinical practice and research.

Safety testing of epimacular brachytherapy with microperimetry and indocyanine green angiography: 12-month results.

PURPOSE: To determine if epimacular brachytherapy is associated with reduced retinal sensitivity or choroidal nonperfusion. METHODS: A prospective intervention case series of 12 participants with neovascular age-related macular degeneration requiring frequent ranibizumab underwent vitrectomy and epimacular brachytherapy. The Strontium 90/Yttrium 90 source delivered a single 24-Gy dose at the center of the treatment zone. The dose attenuated with increasing distance from the source. Microperimetry and indocyanine green angiography were performed at baseline and 12 months. The main outcome measures were mean sensitivity and choroidal nonperfusion. A linear mixed model was used to assess the association between the dose of radiation and the change in mean sensitivity. RESULTS: Mean visual acuity remained within 1 letter of baseline at 12 months (-0.33 ± 13.2 letters). There was no statistically significant change in mean sensitivity within the neovascular age-related macular degeneration lesion area (gain of 0.94 ± 3.25 dB; P = 0.339) or in neighboring unaffected retina (0.66 ± 4.14 dB; P = 0.594), defined using fluorescein angiography. Within the lesion area, mean sensitivity improved by an average of 0.23 ± 0.16 dB (P = 0.006) for every additional gray of radiation received. Indocyanine green angiography failed to demonstrate any choroidal nonperfusion or radiation damage at 12 months after the treatment. CONCLUSION: Stable retinal sensitivity in areas not manifestly affected by neovascular age-related macular degeneration suggests that epimacular brachytherapy does not damage retinal function. The presence of a dose response suggests that the positive effect of epimacular brachytherapy relates more to beta irradiation than vitrectomy.

Preretinal partial pressure of oxygen gradients before and after experimental pars plana vitrectomy.

PURPOSE: To evaluate preretinal partial pressure of oxygen (PO2) gradients before and after experimental pars plana vitrectomy. METHODS: Arteriolar, venous, and intervascular preretinal PO2 gradients were recorded in 7 minipigs during slow withdrawal of oxygen-sensitive microelectrodes (10-µm tip diameter) from the vitreoretinal interface to 2 mm into the vitreous cavity. Recordings were repeated after pars plana vitrectomy and balanced salt solution (BSS) intraocular perfusion. RESULTS: Arteriolar, venous, and intervascular preretinal PO2 at the vitreoretinal interface were 62.3 ± 13.8, 22.5 ± 3.3, and 17.0 ± 7.5 mmHg, respectively, before vitrectomy; 97.7 ± 19.9, 40.0 ± 21.9, and 56.3 ± 28.4 mmHg, respectively, immediately after vitrectomy; and 59.0 ± 27.4, 25.2 ± 3.0, and 21.5 ± 4.5 mmHg, respectively, 2½ hours after interruption of BSS perfusion. PO2 2 mm from the vitreoretinal interface was 28.4 ± 3.6 mmHg before vitrectomy; 151.8 ± 4.5 mmHg immediately after vitrectomy; and 34.8 ± 4.1 mmHg 2½ hours after interruption of BSS perfusion. PO2 gradients were still present after vitrectomy, with the same patterns as before vitrectomy. CONCLUSION: Preretinal PO2 gradients are not eliminated after pars plana vitrectomy. During BSS perfusion, vitreous cavity PO2 is very high. Interruption of BSS perfusion evokes progressive equilibration of vitreous cavity PO2 with concomitant progressive return of preretinal PO2 gradients to their previtrectomy patterns. This indicates that preretinal diffusion of oxygen is not altered after vitrectomy. The beneficial effect of vitrectomy in ischemic retinal diseases or macular edema may be related to other mechanisms, such as increased oxygen convection currents or removal of growth factors and cytokines secreted in the vitreous.

Intravitreal injection of expansile perfluoropropane (c(3)f(8)) for the treatment of vitreomacular traction.

PURPOSE: To study the efficacy of a single intravitreal injection of expansile gas in releasing vitreomacular traction. DESIGN: Retrospective, interventional case series. METHODS: Fifteen eyes of 14 consecutive patients with symptomatic and persistent vitreomacular traction (>3 months' duration) on spectral-domain optical coherence tomography (SD OCT) received a single intravitreal injection of 0.3 mL 100% perfluoropropane (C(3)F(8)) as an alternative to pars plana vitrectomy (PPV). Primary outcome was the number of eyes with complete vitreomacular traction release on OCT 1 month following treatment. Secondary outcomes included changes in visual acuity (VA), foveal contour, central foveal thickness, and maximal foveal thickness 1 month following treatment, and final VA. RESULTS: Mean age (± SD) was 72.1 ± 12.6 years. Mean follow-up was 398.7 ± 174.4 days. Vitreomacular traction was idiopathic in 7 eyes and associated with diabetes in 6. One month following treatment, vitreomacular traction was released in 6 eyes (40%). Three further eyes (20%) had resolution of vitreomacular traction within 6 months, 4 (27%) underwent PPV, and 2 (13%) subsequently declined surgery. Foveal contour was restored in 7 eyes (47%). VA and central foveal thickness were similar 1 month following treatment, but maximal foveal thickness decreased by 65.8 µm (P = .041). Mean final VA decreased 0.03 logMAR units from baseline (P = .536). Eyes with vitreomacular traction release within 1 month had less extensive vitreomacular traction (P = .037), low vitreous face reflectivity, and maximal foveal thickness <500 µm (P = .004) pretreatment. There were no associated adverse events. CONCLUSIONS: Intravitreal C(3)F(8) injection could offer a minimally invasive alternative to PPV in patients with symptomatic and persistent vitreomacular traction. It appears particularly effective in eyes with less extensive vitreomacular traction and low vitreous face reflectivity on SD OCT. Further studies are warranted.

Computerized assessment of intraretinal and subretinal fluid regions in spectral-domain optical coherence tomography images of the retina.

PURPOSE: To evaluate a new computerized segmentation technique for the quantification of intraretinal and subretinal fluid in spectral-domain optical coherence tomography (SD OCT) images of the retina. DESIGN: Prospective, cross-sectional study. METHODS: Thirty-seven B-scan images of 37 patients with exudative age-related macular degeneration were chosen randomly from SD OCT volume scans (1 per volume scan). All hyporeflective areas in the image first were segmented automatically as candidate regions by the program. Researchers who were masked to the candidate region information selected each fluid region from the original image using a single mouse click. The program then delineated the boundary of each region selected and calculated quantitative parameters, including total area of fluid regions if multiple regions were selected. The performance of our technique was validated by comparing the results with the measurements obtained from boundaries manually delineated by 2 masked observers. Time efficiency, agreement with manual delineation, and intraobserver and interobserver agreement of using the program were evaluated. RESULTS: The proposed technique reduced the average processing time per image approximately 6-fold (15 seconds for computerized segmentation vs 90 seconds for manual delineation). There was good agreement between computerized segmentation and manual delineation measured by intraclass correlation coefficient (range, 0.897 to 0.979) and the Dice coefficient (range, 0.721 to 0.785). The proposed technique has excellent intraobserver and interobserver agreement (intraclass correlation coefficient range, 0.998 to 0.999; Dice coefficient range. 0.959 to 0.981). CONCLUSIONS: This computerized segmentation method allows for accurate and fast quantification of fluid in retinal SD OCT images and could assist in monitoring disease progression and evaluating therapeutic intervention.

The rationale of retinal endovascular fibrinolysis in the treatment of retinal vein occlusion: from experimental data to clinical application.

PURPOSE: We describe a retinal endovascular fibrinolysis technique to directly reperfuse experimentally occluded retinal veins using a simple micropipette. METHODS: Retinal vein occlusion was photochemically induced in 12 eyes of 12 minipigs: after intravenous injection of 10% fluorescein (1-mL bolus), the targeted retinal vein segment was exposed to thrombin (50 units) and to Argon laser (100-200 mW) through a pars plana approach. A beveled micropipette with a 30-µm-diameter sharp edge was used for micropuncture of the occluded vein and endovascular microinjection of tissue plasminogen activator (50 µg/mL) in 11 eyes. In one control eye, balanced salt solution was injected. The lesion site was examined histologically. RESULTS: Retinal vein occlusion was achieved in all cases. Endovascular microinjection of tissue plasminogen activator or balanced salt solution led to reperfusion of the occluded retinal vein in all cases. Indicative of successful reperfusion were the following: continuous endovascular flow, unaffected collateral circulation, no optic disk ischemia, and no venous wall bleeding. However, balanced salt solution injection was accompanied by thrombus formation at the punctured site, whereas no thrombus was observed with tissue plasminogen activator injection. CONCLUSION: Retinal endovascular fibrinolysis constitutes an efficient method of micropuncture and reperfusion of an experimentally occluded retinal vein. Thrombus formation at the punctured site can be prevented by injection of tissue plasminogen activator.

The effect of learning curve on the surgical outcome of viscocanalostomy.

PURPOSE: To evaluate the influence of learning curve on the surgical outcome of viscocanalostomy. METHODS: Retrospective, interventional study. Chart review of the first consecutive open-angle glaucoma cases that received viscocanalostomy in 1 institution between July 1996 and June 2000. Overall success was defined as no visual field deterioration; postoperative intraocular pressure (IOP) ≤20 mm Hg; and IOP reduction ≥30% compared with baseline values with or without medication. When medications were not required, success was defined as complete. Demographic, procedural, and postoperative data were tabulated and analyzed. PRIMARY OUTCOME MEASURES: overall and complete success rates. SECONDARY OUTCOME MEASURES: number of glaucoma medications and surgical complications. RESULTS: A total of 180 cases were analyzed. Mean follow-up (±SD) was 28.9±5.9 months (range, 12-36 mo). Overall success has significantly improved from 64% to 91% when comparing the first 45 to the last 45 cases of the series (Mantel-Cox, P=0.005). Similarly, complete success has significantly improved from 38% to 73% (Mantel-Cox, P=0.004). The mean number of glaucoma medication (±SD) significantly decreased from 2.58±0.94 before surgery to 0.53±0.79 after surgery (Wilcoxon, P<0.001). Surgical complications decreased from 16 in the first 45 cases to 10 in the last 45 cases without reaching statistical significance (Pearson χ, P=0.315). CONCLUSIONS: Viscocanalostomy appears to safely reduce IOP in cases with medically uncontrolled open-angle glaucoma. Mastering viscocanalostomy procedure is achievable after the first 40 cases.

Polypoidal choroidal vasculopathy masquerading as neovascular age-related macular degeneration refractory to ranibizumab.

PURPOSE: To report a neovascular age-related macular degeneration pattern refractory to ranibizumab. DESIGN: Retrospective, observational case series. METHODS: Between March and May 2009, cases with neovascular age-related macular degeneration refractory to ranibizumab were investigated with indocyanine green angiography. We identified 12 eyes of 12 patients with polypoidal choroidal vasculopathy. Refractory to treatment were defined cases with persistent subretinal or intraretinal fluid, or both, after 3 or more consecutive monthly ranibizumab injections regardless of best-corrected visual acuity. RESULTS: All patients identified were white, of whom 6 were male. Mean age ± standard deviation at presentation was 75 ± 5.6 years (range, 64 to 81 years); diagnosis, based on fluorescein angiography, comprised occult choroidal neovascularization (CNV) in 8 eyes, and 1 case each of classic-no-occult CNV, minimally classic CNV, predominantly classic CNV, and retinal angiomatous proliferation. Eight cases had switched from courses of other therapy (5 pegaptanib, 1 photodynamic therapy, 1 photodynamic therapy then pegaptanib, 1 bevacizumab). After a mean follow-up of 10.2 ± 4.8 months (range, 3 to 18 months) and 7.6 ± 3.9 ranibizumab injections (range, 3 to 14 injections), indocyanine green angiography revealed polypoidal choroidal vasculopathy lesions in all cases. CONCLUSIONS: Neovascular age-related macular degeneration refractory to a course of ranibizumab injections may harbor polypoidal choroidal vasculopathy. In such cases, indocyanine green angiography is a valuable tool for revealing polypoidal lesions.

Automated segmentation of foveal avascular zone in fundus fluorescein angiography.

PURPOSE. To describe and evaluate the performance of a computerized automated segmentation technique for use in quantification of the foveal avascular zone (FAZ). METHODS. A computerized technique for automated segmentation of the FAZ using images from fundus fluorescein angiography (FFA) was applied to 26 transit-phase images obtained from patients with various grades of diabetic retinopathy. The area containing the FAZ zone was first extracted from the original image and smoothed by a Gaussian kernel (sigma = 1.5). An initializing contour was manually placed inside the FAZ of the smoothed image and iteratively moved by the segmentation program toward the FAZ boundary. Five tests with different initializing curves were run on each of 26 images to assess reproducibility. The accuracy of the program was also validated by comparing results obtained by the program with the FAZ boundaries manually delineated by medical retina specialists. Interobserver performance was then evaluated by comparing delineations from two of the experts. RESULTS. One-way analysis of variance indicated that the disparities between different tests were not statistically significant, signifying excellent reproducibility for the computer program. There was a statistically significant linear correlation between the results obtained by automation and manual delineations by experts. CONCLUSIONS. This automated segmentation program can produce highly reproducible results that are comparable to those made by clinical experts. It has the potential to assist in the detection and management of foveal ischemia and to be integrated into automated grading systems.

The vasodilatory effect of juxta-arteriolar microinjection of endothelinA receptor inhibitor in healthy and acute branch retinal vein occlusion minipig retinas.

Purpose. To investigate the effect of the endothelin(A) receptor inhibitor BQ-123 on the retinal arteriolar vasculature in minipig retinas in normal eyes and eyes with acute branch retinal vein occlusion (BRVO). Methods. Seven healthy eyes of seven minipigs and six eyes of six minipigs with experimental BRVO were evaluated under systemic anesthesia. An intravitreal juxta-arteriolar microinjection of 30 microL BQ-123 0.61 microg/mL (pH 7.4) was performed in all but one eye from each group, into which the physiologic saline vehicle alone was injected. Vessel-diameter changes were measured with a retinal vessel analyzer. Results. In healthy minipig retinas (n = 6), arteriolar diameter (+/-SD) increased 6.19% +/- 3.55% (P < 0.05), 25.98% +/- 2.37% (P < 0.001), 23.65% +/- 1.2% (P < 0.001), and 16.84% +/- 1.95% (P < 0.001), at 1, 5, 10, and 15 minutes, respectively, after BQ-123 microinjection. Two hours after experimental BRVO (n = 5), the retinal arteriolar diameter had decreased (13.07% +/- 5.7%; P < 0.01). One, 5, 10, and 15 minutes after BQ-123 microinjection, retinal arteriolar diameter had increased by 7.14% +/- 3.3% (P < 0.01), 26.74% +/- 7.63% (P < 0.001), 23.67% +/- 6.4% (P < 0.001), and 16.09% +/- 3.41% (P < 0.001), respectively. Vehicle only injection had no vasoactive effect on physiologic or BRVO retinas. Conclusions. A significant increase in retinal arteriolar diameter was demonstrated after juxta-arteriolar BQ-123 microinjection in healthy and in acute BRVO minipig retinas. The results suggest a role for endothelin-1 in maintaining retinal basal arteriolar tone. Reversing the BRVO-related vasoconstriction by juxta-arteriolar BQ-123 microinjection could bring a new perspective to the management of BRVO.

Effect of systemic nitric oxide synthase inhibition on optic disc oxygen partial pressure in normoxia and in hypercapnia.

PURPOSE: To investigate the effect of systemic nitric oxide synthase (NOS) inhibition on optic disc oxygen partial pressure (PO(2)) in normoxia and hypercapnia. METHODS: Intervascular optic disc PO(2) was measured in 12 anesthetized minipigs by using oxygen-sensitive microelectrodes placed <50 microm from the optic disc. PO(2) was measured continuously during 10 minutes under normoxia, hyperoxia (100% O(2)), carbogen breathing (95% O(2), 5% CO(2)), and hypercapnia (increased inhaled CO(2)). Measurements were repeated after intravenous injection of N(omega)-nitro-L-arginine methyl ester (L-NAME) 100 mg/kg. Intravenous L-arginine 100 mg/kg was subsequently given to three animals. RESULTS: Before L-NAME injection, an increase was observed in optic disc PO(2) during hypercapnia (DeltaPO(2) = 3.2 +/- 1.7 mm Hg; 18%; P = 0.001) and carbogen breathing (DeltaPO(2) = 12.8 +/- 5.1 mm Hg; 69%; P < 0.001). Optic disc PO(2) in normoxia remained stable for 30 minutes after L-NAME injection (4% decrease from baseline; P > 0.1), despite a 21% increase of mean arterial pressure. Optic disc PO(2) increase under hypercapnia was blunted after L-NAME injection (DeltaPO(2) = 0.6 +/- 1.1 mm Hg; 3%; P > 0.1), and this effect was reversible by L-arginine. Moreover, L-NAME reduced the response to carbogen by 29% (DeltaPO(2) = 9.1 +/- 4.4 mm Hg; 49%; P = 0.01 versus before L-NAME). The response to hyperoxia was not affected. CONCLUSIONS: Whereas systemic NOS inhibition did not affect optic disc PO(2) in normoxia, a blunting effect was noted on the CO(2)-induced optic disc PO(2) increase. Nitric oxide appears to mediate the hypercapnic optic disc PO(2) increase.

Lactate-induced retinal arteriolar vasodilation implicates neuronal nitric oxide synthesis in minipigs.

PURPOSE: To investigate the role of neuronal nitric oxide (NO) synthesis in the retinal vasodilatory response to lactate in minipigs. METHODS: Thirteen eyes of 13 minipigs were evaluated. Ten eyes received an intravenous infusion of N(omega)-nitro-L-arginine methyl ester (L-NAME). After 1 hour, the same eyes received an intravitreous juxta-arteriolar microinjection of 30 microL of L-lactate 0.5 M (pH 7.4) through a micropipette. Ten minutes later, 9 of 10 eyes received an intravitreous juxta-arteriolar microinjection of 30 microL of L-NAME 0.01 M (pH 7.4), and 1 received physiologic saline solution (PSS). The remaining three eyes received a microinjection of 30 microL of L-lactate 0.5 M (pH 7.4), without intravenous or intravitreous L-NAME. RESULTS: The three eyes that received juxta-arteriolar injection of L-lactate only showed a reproducible increase in retinal arteriolar diameter that persisted during the entire study period (maximum effect at 20 minutes, 40.9% +/- 3.2%). Retinal arteriolar diameter decreased by 4.1% 1 hour after intravenous L-NAME when compared with baseline but the difference did not reach significance. The juxta-arteriolar injection of L-lactate induced a significant increase in retinal arteriolar diameter (22.7% and 28.7% at 5 and 10 minutes, respectively; P < 0.01), followed by a significant decrease (8.6%; P < 0.01) 10 minutes after juxta-arteriolar injection of L-NAME. Injection of PSS had no effect on retinal arteriolar diameter. CONCLUSIONS: Juxta-arteriolar administration of L-lactate induced vasodilation, which was also observed with continuous intravenous infusion of L-NAME. Moreover, juxta-arteriolar L-NAME microinjection significantly suppressed the vasodilatory effect of L-lactate. These data suggest that neuronal-derived NO is an important mediator of lactate-induced vasodilation in minipigs.

Primary vitrectomy without scleral buckling for pseudophakic rhegmatogenous retinal detachment.

PURPOSE: To report the anatomic and functional results of primary vitrectomy without scleral buckling for the treatment of pseudophakic rhegmatogenous retinal detachment (PsRD). DESIGN: Prospective, nonrandomized surgical technique study. METHODS: One hundred eyes of 98 patients with PsRD were operated by vitrectomy alone. Internal subretinal fluid drainage, cryocoagulation and/or endolaser and fluid-air exchange with sulfur hexafluoride 20% was applied in all cases. The preoperative and postoperative characteristics were analyzed. Main outcome measures were anatomic success rates after initial surgical intervention and after reoperation for primary failures, visual outcome at the last follow-up visit, and complications. RESULTS: Mean follow-up +/- standard deviation (SD) was 12 +/- 6.3 months (range, seven to 36 months). Mean final visual acuity +/- SD was 0.42 +/- 0.45 logarithm of the minimum angle of resolution (logMAR) compared with 0.95 +/- 0.73 logMAR before surgery (P < .01). Mean number +/- SD of retinal breaks found before surgery was 1.36 +/- 1.12 (range, zero to five), and an additional 1.58 +/- 2.26 (range, zero to 15) retinal breaks were found during surgery. The retina was reattached successfully after a single surgery in 92 eyes (92%). Recurrence of retinal detachment occurred in eight eyes (8%), caused by proliferative vitreoretinopathy in six eyes (75%) and by new breaks in two eyes (25%). Final anatomic reattachment was obtained in these cases after a mean of 1.75 subsequent operations. Three eyes required permanent silicone oil tamponade so that final anatomic success was achieved in 97 eyes (97%). The most common postoperative complication was ocular hypertonia of more than 21 mm Hg, observed in 36 (36%) eyes, which was managed successfully. CONCLUSIONS: Primary vitrectomy without scleral buckling provides a high anatomic success rate in eyes with PsRD and is associated with few complications.

Optical coherence tomography and multifocal electroretinogram findings in chronic solar retinopathy.

PURPOSE: To correlate the structural and functional retinal defects, which are induced photochemically in chronic solar retinopathy. DESIGN: Observational case report. METHODS: Four emmetropic eyes of two patients, previously diagnosed with chronic solar retinopathy, were evaluated by optical coherence tomography (OCT), multifocal electroretinography, and fluorescein angiography. RESULTS: Visual acuity ranged from 20/80 to 20/50 and all subjects had central and steady fixation. In all eyes, OCT demonstrated a hyporeflective space at the level of outer retinal and retinal pigment epithelium (RPE) layers, which was limited to the fovea. The foveal contour was preserved with normal vitreoretinal interface. Multifocal electroretinogram (mfERG) trace array of the first-order kernel demonstrated attenuated responses extending to a larger area, the para- and perifovea. A foveal RPE window defect was angiographically evident in all cases. CONCLUSIONS: A model of centrifugal neuronal damage is proposed for chronic solar retinopathy, with more functional than structural neuroretinal defects.

Diabetic retinopathy.

INTRODUCTION: Diabetic retinopathy is the most common cause of blindness in the UK, with older people and those with worse diabetic control, hypertension, and hyperlipidaemia being most at risk. Diabetic retinopathy can cause microaneurysms, haemorrhages, exudates, changes to blood vessels, and retinal thickening. METHODS AND OUTCOMES: We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of treatments in people with diabetic retinopathy? What are the effects of treatments for vitreous haemorrhage? We searched: Medline, Embase, The Cochrane Library and other important databases up to November March 2007 (Clinical Evidence reviews are updated periodically, please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). RESULTS: We found 29 systematic reviews, RCTs, or observational studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. CONCLUSIONS: In this systematic review we present information relating to the effectiveness and safety of the following interventions: peripheral retinal laser photocoagulation, focal and grid laser photocoagulation for maculopathy, corticosteroids for macular oedema, and vitrectomy for vitreous haemorrhage.

Phacoviscocanalostomy for open-angle glaucoma with concomitant age-related cataract.

PURPOSE: To evaluate the efficacy and safety of combined viscocanalostomy and phacoemulsification (phacoviscocanalostomy) for medically uncontrolled open-angle glaucoma (OAG) with concomitant age-related cataract. DESIGN: Prospective, noncomparative, interventional case-series study. METHODS: Phacoviscocanalostomy was performed on 50 eyes of 50 consecutive patients with medically uncontrolled OAG and clinically significant age-related cataract. Surgical outcome was defined as an overall success by the following criteria: no visual field deterioration; no optic-neuropathy progression; postoperative intraocular pressure (IOP) /= 30% compared to baseline values with or without medication. When medications were not required, success was defined as complete. The surgical outcome and the complication rates were documented and analyzed up to 36 months postoperatively. RESULTS: Mean follow-up (+/-SD) was 29.02 +/- 7.09 months. Mean, baseline IOP (+/-SD) had significantly decreased from 23.51 +/- 4.48 mmHg to 14.06 +/- 1.64 mmHg at the last follow-up visit for each patient (p < 0.001). The overall success was 94% at 12 months, 92% at 24 months, and 82% at 36 months. The success was complete in 74% at 12 months, and in 67% at 24 months and at 36 months. No serious complications were documented. CONCLUSION: Phacoviscocanalostomy can be considered an efficient and safe alternative surgical modality for medically uncontrolled OAG with concomitant age-related cataract.

Primary viscocanalostomy for juvenile open-angle glaucoma.

PURPOSE: To evaluate the efficacy and safety of primary viscocanalostomy for medically uncontrolled juvenile open-angle glaucoma (JOAG). DESIGN: Prospective, noncomparative, interventional case-series study. METHODS: The study included 20 eyes of 20 consecutive patients with medically uncontrolled JOAG who were treated by viscocanalostomy at one institution. No surgical or laser procedure preceded viscocanalostomy. Surgical outcome was defined as an overall success by the following criteria: no visual field deterioration, no optic-neuropathy progression, postoperative intraocular pressure IOP < or =20 mm Hg, and IOP reduction > or =30% compared with baseline values with or without medication. When medications were not required, success was defined as complete. Cases that did not fulfill the aforementioned criteria and cases in which a surgical revision or further goniopuncture was performed were defined as a failure. RESULTS: Gender distribution was similar. Fourteen eyes belonged to the white race; five eyes belonged to the black race, and one eye belonged to Arab ethnicity. Mean age (+/-SD) at operation was 33.77 +/- 6.16 years, with the mean preoperative IOP (+/-SD) at 22.9 +/- 4.77 mm Hg. Thirty-six months after operation, 16 cases (80%) were considered an overall success. In 11 cases (55%), success was complete. Four cases (20%) were considered failures. No serious complications were documented either during or after operation. In two cases (10%), we documented a spontaneously reabsorbed microhyphema. Trabeculo-Descemet-membrane microperforation occurred in two cases (10%). In two other cases (10%), Trabeculo-Descemet-membrane perforation occurred and was accompanied by iris prolapse that needed peripheral iridectomy. CONCLUSION: Primary viscocanalostomy can efficiently and safely reduce intraocular pressure in cases of medically uncontrolled JOAG and provide a rational alternative to conventional surgical modalities.

Cavernous sinus thrombosis elicited by a central retinal vein venous stasis retinopathy.

BACKGROUND: Central retinal vein occlusion is a relatively common retinal disorder in the elderly, and those with cardiovascular or thrombophilic risk factors are at increased risk. Although still unsatisfying, some treatments for the acute and chronic phases have been established based on randomized studies. However, for rare conditions mimicking central retinal vein occlusion, treatment of the acute phase should be targeted at etiology. A rare condition mimicking central retinal vein occlusion in a 70-year-old man is presented and discussed. METHODS: A 70-year-old man was admitted to the hospital for isovolemic hemodilution related to a central retinal vein occlusion of the elderly, after a sudden decrease in visual acuity to 0.1. RESULTS: Clinical and laboratory work-up demonstrated a venous stasis retinopathy, related to an atypical cavernous sinus thrombosis of undetermined origin. The patient had experienced in the past 6 months intermittent diplopia and an irreducible conjunctival hyperemia. Hemodilution was dismissed. Soon after initiation of anticoagulation therapy, the patient's clinical signs and symptoms improved. Final visual acuity was 0.8. CONCLUSION: Venous stasis retinopathy secondary to cavernous sinus thrombosis is rare. However, careful clinical examination and extensive laboratory work-up is needed to exclude central retinal vein occlusion not associated with common vascular pathologies of the elderly.