REPRODUCIBILITY AND RELIABILITY OF OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY FOR FOVEAL AVASCULAR ZONE EVALUATION AND MEASUREMENT IN DIFFERENT SETTINGS.

PURPOSE: Optical coherence tomography angiography (OCTA) allows delineating the foveal avascular zone (FAZ) easily and noninvasively. The present study aims to test reproducibility and reliability of FAZ evaluation by means of OCTA in different settings. METHODS: Twenty-four eyes of 24 normal subjects were investigated using AngioVue OCTA Imaging System. A series of OCTA acquisitions were taken both in basal and in different experimental settings after vasoactive stimuli. Images were evaluated separately by two operators and FAZ area was measured both manually and using the built-in automated measurement tool. RESULTS: No differences for FAZ area were found in the repetition of basal acquisitions, neither in manual nor in automated measurement (0.215 ± 0.06 vs. 0.216 ± 0.07, and 0.268 ± 0.05 vs. 0.264 ± 0.09, first vs. second basal measurement in square millimetres for manual and automated evaluation, P = 0.25 and P = 0.35, respectively). Interoperators correlation was optimal (r = 0.978 [95% CI 0.981-0.976]). No differences were found among the other settings, which included first basal and then repeated (second) in the morning, after flickering light stimulus, after a Bruce treadmill stress test, after 30 minutes dark adaptation, and basal in the evening, neither in automated nor in manual measurements. Automated measurements for nonflow areas provided significantly larger diameters than manual ones. CONCLUSION: AngioVue OCTA Imaging System produces highly reproducible FAZ images with a high interoperators concordance level. Optical coherence tomography angiography capability to detect FAZ area seems not to be influenced by any of the vasoactive stimuli considered in the current study. Nonflow areas seem to be larger when measured automatically than manually.

DYNAMIC AND STATIC VESSEL ANALYSIS IN PATIENTS WITH RETINITIS PIGMENTOSA: A Pilot Study of Vascular Diameters and Functionality.

PURPOSE: To evaluate in vivo the vascular anatomy and functionality of early manifestation retinitis pigmentosa (RP) by means of a dynamic and static vessel analyzer. METHODS: Fourteen patients with early RP and 14 normal subjects were consecutively enrolled in this observational, prospective study. Each patient underwent a complete ophthalmologic examination, including dynamic and static retinal vessel analysis using the Dynamic Vessel Analyzer. RESULTS: The patients with RP and the control group were well matched in age and sex. Patients with RP had a mean best-corrected visual acuity of 20/25 (range: 20/40-20/20). Dynamic vessel analysis performed in patients with RP showed an arterial and venous dilation during flicker stimulation of 5.28 ± 1.7% and 4.07 ± 1.78%, respectively. Only arterial dilation was statistically different compared with control subjects (3.33 ± 0.99%, P = 0.0062). Static retinal vessel analysis in patients with RP showed a decreased mean central retinal artery equivalent (P < 0.001) and central retinal vein equivalent (P < 0.001) compared with control subjects. By contrast, the arterial-to-venous ratio was similar in both groups (RP: 0.79 ± 0.11, control group 0.86 ± 0.04, P = 0.072). CONCLUSION: Our data confirm that retinal arterial and venous narrowing is present at an early stage in patients affected by RP. However, dynamic vessel analysis shows how the retina of patients with RP with no best-corrected visual acuity loss presents an augmented artery dilation response compared with normal subjects and retained neurovascular coupling.

Static characteristics and dynamic functionality of retinal vessels in longer eyes with or without pathologic myopia.

PURPOSE: To analyze major retinal vessels in eyes with high myopia by means of the Dynamic Vessel Analyzer (DVA) in order to gather insight on retinal vascular functionality and better understand why these eyes are resistant to diabetes-related changes. METHODS: A total of 20 high-myopia eyes with pathologic myopia, 20 high-myopia eyes without pathologic myopia and 20 age- and sex-matched control subjects (without pathologic myopia) were included and compared. RESULTS: Dynamic analysis showed mean arterial dilation of 2.44 ± 1.59 % in high-myopia eyes with pathologic myopia, 2.67 ± 1.17 in high-myopia without pathologic myopia eyes, and 3.28 ± 1.46 % in healthy eyes. Mean venous dilation was 3.45 ± 1.82 %, 3.57 ± 1.72, and 4.45 ± 2.72 % respectively. Static analysis in high myopia eyes with pathologic myopia showed a mean central retinal artery equivalent (CRAE) of 171.6 ± 24.3, a mean central retinal vein equivalent (CRVE) of 199.5 ± 27.73, and a mean arteriovenous ratio (AVR) of 0.86 ± 0.01. In patients with high myopia without pathologic myopia, we found a mean CRAE of 173 ± 21.6, a mean CRVE of 198.2 ± 18.8, and a mean AVR of 0.87 ± 0.1. In control subjects, mean CRAE was 190.3 ± 11.93, mean was CRVE 215.7 ± 13.30, and mean AVR was 0.88 ± 0.04. CONCLUSIONS: Static and dynamic tests revealed that in high-myopia eyes, the vessels at the retinal posterior pole have reduced diameter, but are functionally comparable to control subjects. This supports the hypothesis of reduced oxygen consumption in high-myopia eyes.

Correlation of SD-OCT findings and visual function in patients with retinitis pigmentosa.

PURPOSE: To describe the morphological macular changes detected by spectral domain optical coherence tomography (SD-OCT) in eyes with retinitis pigmentosa (RP) and to analyze their correlation with the visual function. METHODS: Twenty-two patients (44 eyes) patients affected by RP were recruited. The following structures were evaluated on SD-OCT: outer plexiform layer (OPL), outer nuclear layer (ONL), external limiting membrane (ELM), photoreceptor inner/outer segment (IS/OS) junction, photoreceptor outer segment/retinal pigmented epithelium (OS/RPE) junction, inner limiting membrane thickening (ILMT), ganglion cell complex (GCC), and cystoid macular edema (CME). The relation between each SD-OCT finding and BCVA was evaluated at uni- and multivariate analysis. RESULTS: Mean age and mean best-corrected visual acuity (BCVA) were 51 ± 17.5 years and 0.4 ± 0.5 LogMAR, respectively. Univariate linear regression model revealed a correlation between BCVA and the absence of ELM, IS/OS, ONL, and OS/RPE layers (R (2) values were, respectively, 0.51, 0.57, 0.48, and 0.68, with p values all <0.0001). At multivariate regression analysis, the absence of OS/RPE and ELM layers remained the only variables independently associated with a decrease of BCVA (R (2) = 0.85, t = 3.49, p = 0.0014). CONCLUSIONS: Data show that in patients afflicted with RP, ELM and OS/RPE layers are independently associated with BCVA on multivariate regression analysis. These results highlight the key-role of external retinal layers in determining the visual function impairment attributable to RP.

Acute central serous chorioretinopathy: a correlation study between fundus autofluorescence and spectral-domain OCT.

PURPOSE: To evaluate the correlation between fundus autofluorescence (FAF) and spectral-domain OCT (SD-OCT) morphological analysis in eyes with acute central serous chorioretinopathy (CSCR). METHODS: Thirty-one patients with a first episode of CSCR and symptom duration of less than 6 weeks were prospectively enrolled. FAF and SD-OCT examination were performed at baseline and at 2-month intervals. Main outcome measure was the correlation between FAF and SD-OCT retinal morphology. RESULTS: At baseline, 30/31 and 29/31 eyes showed a macular hypo-AF, corresponding to the neurosensory retinal detachment (SRD), on shortwave-FAF (SW-FAF) and near-infrared-FAF (NIR-FAF), respectively. While the SRD resolved, both FAF techniques showed a granular hyper-AF in 31 eyes. At first examination, SD-OCT confirmed the SRD with a photoreceptor outer-segment (OS) elongation in all cases. During SRD resolution, the photoreceptor layer appeared thicker and fragmented. Multiple hyper-reflective precipitates were detected in the outer plexiform and nuclear layer and between the photoreceptors and appeared colocalized with the hyper-AF dots composing the granular hyper-AF. After SRD resolution, the hypo-AF area reverted to a normal pattern on SW-FAF in all eyes and in 25/31 on NIR-FAF. Examination at 12 months showed that the granular hyper-AF was still detectable in 54 % eyes, whereas 6/31 eyes showed hypo-AF dots on NIR-FAF. On SD-OCT, the junction IS/OS was identifiable in 11/31 eyes soon after the SRD resolution and appeared completely restored in all patients at the final visit. CONCLUSION: The simultaneous acquisition of FAF and SD-OCT provides detailed findings of retinal abnormalities of CSCR and may help to understand the evolving process linked to CSCR.

DYNAMIC AND STATIC RETINAL VESSEL ANALYSES IN PATIENTS WITH MACULAR EDEMA SECONDARY TO RETINAL VEIN OCCLUSION.

PURPOSE: To investigate the vasomotor responses and diameter of retinal vessels in patients with macular edema secondary to retinal vein occlusion (RVO). METHODS: A total of 18 eyes of 18 RVO patients were consecutively included and compared with age- and sex-matched controls. Participants underwent an examination with optical coherence tomography and dynamic and static retinal vessel analyses using the Dynamic Vessel Analyzer. RESULTS: Dynamic vessel analysis in RVO showed mean maximum venous and arterial dilation of 2.22 ± 1.23% and 1.87 ± 1.41%, respectively, as compared with 5.05 ± 2.75% (P = 0.001) and 3.95 ± 1.44% (P = 0.0004), respectively, in controls. Static retinal vessel analysis in RVO revealed a mean arteriovenous ratio (AVR) of 0.74 ± 0.09 versus 0.90 ± 0.04 (P < 0.0001) in controls. Mean AVRs of occluded and nonoccluded quadrants in RVO were 0.71 ± 0.13 and 0.85 ± 0.19, respectively; in the corresponding quadrants of controls, mean AVRs were 0.90 ± 0.19 (P < 0.0001) and 0.86 ± 0.17 (P = 0.89), respectively. In branch RVO patients, mean AVRs of occluded versus nonoccluded quadrants were 0.70 ± 0.06 and 0.90 ± 0.22 (P = 0.002), respectively. CONCLUSION: In patients with macular edema secondary to RVO, dynamic vessel analysis showed an impairment of both venous and arterial motility and/or reactivity and static vessel analysis showed a reduced AVR indicating a general enlargement of the retinal venous network. Moreover, in branch RVO patients, static analysis demonstrated that retinal vessels could actually be uninvolved by the occlusive process in areas spared by disease.

Intravitreal ranibizumab for choroidal neovascularization with large submacular hemorrhage in age-related macular degeneration.

PURPOSE: To evaluate the effects of intravitreal ranibizumab injections in the treatment of choroidal neovascularization with large submacular hemorrhage secondary to age-related macular degeneration. METHODS: Prospective interventional case series. Patients presenting occult choroidal neovascularization with flat large submacular hemorrhage >50% of the entire lesion were considered. The protocol required 3 monthly consecutive injections, followed by repeat injections over the 12-month follow-up on the basis of optical coherence tomography parameters and angiographic features. RESULTS: Twenty-three patients were enrolled in the study and prospectively followed up. Mean best-corrected visual acuity and mean central macular thickness at the baseline were 0.82 ± 0.22 (logarithm of the minimum angle of resolution ± standard deviation) and 342 ± 56 µm, respectively. At 12-month examination, mean visual acuity improved significantly to 0.68 ± 0.41 (P = 0.04), and mean central macular thickness decreased to 236 ± 26 µm (P < 0.0001). A progressive resolution of macular bleeding was registered in 22 of 23 patients. No side effect or complication was registered. CONCLUSION: Intravitreal ranibizumab can be considered a beneficial approach for the management of choroidal neovascularization with flat large submacular hemorrhage secondary to age-related macular degeneration.

Intravitreal ranibizumab for naive extrafoveal choroidal neovascularization secondary to age-related macular degeneration.

PURPOSE: To investigate the effect of intravitreal ranibizumab on extrafoveal choroidal neovascularization secondary to age-related macular degeneration. METHODS: Eighteen eyes affected by extrafoveal choroidal neovascularization secondary to age-related macular degeneration were prospectively enrolled in this study. After an initial intravitreal ranibizumab, all patients were reevaluated monthly over 12 months of follow-up. Further retreatments were performed on a pro re nata basis, depending on detection of any type of fluid on optical coherence tomography and/or the presence of leakage on fluorescein angiography. Primary outcome measures were mean changes in best-corrected visual acuity and the proportion of eyes gaining at least 15 letters (3 Early Treatment Diabetic Retinopathy Study [ETDRS] lines) at the end of the follow-up. Secondary outcome measures were central macular thickness variations and changes in choroidal neovascularization size. RESULTS: Mean best-corrected visual acuity presented a significant improvement during the follow-up period, being 0.3 ± 0.2 logMAR at baseline and 0.2 ± 0.2 logMAR at the 12-month examination (P < 0.001). An improvement of at least 3 EDTRS lines was achieved by 6 eyes (33.3%), whereas 6 patients (33.3%) gained 1 to 2 lines. The mean central macular thickness at baseline was 314 ± 87 µm, changing to 268 ± 65 µm at the 12-month examination (P = 0.003). The mean lesion size was 1.4 ± 1.4 mm and remained stable throughout the follow-up, being 1.8 ± 2.9 mm at 12 months (P = 0.64). CONCLUSION: Intravitreal ranibizumab administered after a pro re nata regimen with monthly evaluation is a beneficial approach for the management of extrafoveal choroidal neovascularization secondary to age-related macular degeneration over 12 months of follow-up. Further studies are warranted to confirm our preliminary results.

Fluorescein angiography and spectral-domain optical coherence tomography for monitoring anti-VEGF therapy in myopic choroidal neovascularization.

AIM: To evaluate the agreement between fluorescein angiography (FA) and spectral-domain optical coherence tomography (SD-OCT) in detecting myopic choroidal neovascularization (CNV) activity during bevacizumab treatment. METHODS: Thirty-four patients with subfoveal myopic CNV were prospectively enrolled. FA and SD-OCT were performed at baseline and at all planned monthly visits. After the first injection, additional treatments were administered following detection of fluid on SD-OCT and/or leakage on FA. κ-Analysis was performed to examine the agreement between FA and SD-OCT. RESULTS: At baseline, FA and SD-OCT agreed in 26/34 cases (κ=0.23); sensitivity and specificity were 77.4 and 66.7%, respectively. Seven eyes presented leakage on FA with no fluid on SD-OCT, 1 case showed intraretinal fluid on SD-OCT and no leakage on FA. At the 1-month examination, specificity and κ-value improved, and 30/34 cases showed complete concordance. At the 3- and 4-month examinations, a discordance was noted in 6 cases. From the 5-month examination on, a correspondence was achieved in at least 30/34 cases and reached a perfect match in 11 sessions. CONCLUSIONS: Our study confirms the key role of FA in diagnosing myopic CNV. It seems possible there may be a role for SD-OCT in assisting FA to monitor the myopic CNV activity during anti-vascular endothelial growth factor antibody treatment.

Peripapillary pachychoroid syndrome treated with dexamethasone implant: A case report.

PURPOSE: To describe a case of peripapillary pachychoroid syndrome (PPS) in a diabetic patient with cystoid macular edema (CME), treated with intravitreal dexamethasone implant (IDI) injection. This report also illustrates the history of the disease after repeated IDI and dexamethasone topical treatment. METHODS: A case report. RESULTS: A 77-year old male patient with PPS and good diabetic control was treated with dexamethasone implant for CME. After an initial morphofunctional improvement associated with a first IDI, the disease relapsed after the second dexamethasone implant injection. This was associated with a significant increase in both intraretinal fluid and choroidal thickness, with subsequent visual acuity (VA) decrease. At this point, a topical dexamethasone treatment was performed and, despite a morphological improvement, VA worsened compared with baseline, likely because of anatomical damage. CONCLUSION: In this report, the importance of the recognition of PPS is underlined and the possible occurrence of a "rebound" effect due to repeated IDI is described.

Review and perspectives on pharmacological vitreolysis.

The vitreous is involved in multiple diseases when an incomplete posterior vitreous detachment (PVD) occurs. An incomplete PVD can lead to several pathological conditions. Such visually threatening conditions are traditionally of exclusive surgical interest. In contrast, pharmacological vitreolysis is the effort to reduce or eliminate the pathogenetic role of the vitreous solely by means of drug delivery. Here we aim to review and summarize the evidence available to date about this challenging new approach.

Wide-angle 3D viewing system with valved trocar applied to chandelier-assisted scleral buckling.

INTRODUCTION: Scleral buckling (SB) has been the first technique to repair a retinal detachment (RD) and it is still largely in use. Pars plana vitrectomy (PPV) is currently the most common technique, being more versatile and easier to approach. Here we report on a new SB variant, modified by using some of the latest technological advances borrowed from PPV. METHODS: We retrospectively reviewed all our SB cases from November 2017 to November 2018, all of them performed with a chandelier, mounted on valved trocar, to provide 3D wide-angle viewing. 107 eyes of 107 patients (mean age of 59 ± 8 years, 61 [57%] males) underwent primary uncomplicated RD surgery using this modified SB technique and were enrolled for this study. RESULTS: In this article, the technique is thoroughly described with an online video presentation. Briefly, thanks to valved trocar insertion, it combines the latest breakthroughs in the field of PPV viewing systems with traditional SB surgery. Our first-year data reveal a primary success rate of 94% (101 cases out of 107) at 3 months follow-up. A hidden retinal lesion, undetected at clinical pre-operative evaluation, was found intraoperatively in 12 (8.9%) cases. CONCLUSION: The use of a digital three-dimensional (3D) visualization system, coupled with the positioning of a single 25 gauge valved trocar with chandelier, dramatically simplifies the traditional SB and flattens its learning curve, making this procedure more accessible to young surgeons. In addition, the better visualization capability yields to higher possibility to detect and treat all retinal lesions.

Covid-19 and acute conjunctivitis: Controversial data from a tertiary refferral Italian center.

PURPOSE: Although acute conjunctivitis has been listed from the beginning as a possible sign of COVID-19, the likelihood of this association remains unclear. The aim of this study was to investigate the relationship between COVID-19 and conjunctivitis. METHODS: In this retrospective, observational study, we recruited all patients with signs and symptoms of acute conjunctivitis seen at the Eye Emergency Department (ED), Turin Eye Hospital, between 01/01/2020 and 12/05/2020 and cross-checked our data with the Piedmont Region online COVID-19 registry in the same period. RESULTS: Among 10,065 patients seen at our ED during the timespan considered, 88 underwent a nasopharyngeal swab (NS) for SARS-CoV-2 detection within 4 weeks before/after our examination. On average, NS was performed -0.72 ± 1.8 weeks before/after eye examination. Of the 77 patients with a negative NS, 26 (33.8%) had a diagnosis of acute conjunctivitis, whereas the remaining 51 (66.2%) had other eye disorders. Among the 11 patients with COVID-19, 7 (63,6%) had a diagnosis of acute conjunctivitis. We found a non-statistically significant increase in NS positivity rate (21.2%) among cases examined at our ED for acute conjunctivitis, compared to the NS positivity rate (7.3%) in patients examined for all other eye conditions (p = 0.092). The Odds Ratio of having a positive NS in patients with acute conjunctivitis was 3.43 (95% I.C. = 0.9-12.8, p = 0.06). Considering online-registry data of Turin population during the same time-span, among 2441 positive NS cases only 27 (1.1%) presented with acute conjunctivitis. CONCLUSION: Our results do not reveal a statistically significant correlation between COVID-19 and acute conjunctivitis. SYNOPSIS: The present study analyzes retrospectively data from a tertiary eye referral center to investigate the relationship between COVID-19 infection and conjunctivitis.

Heads-up 3D eye surgery: Safety outcomes and technological review after 2 years of day-to-day use.

BACKGROUND: 3D heads-up visualization systems are aimed to improve the surgical experience by providing high-resolution imaging. Objective of our study is to analyze, over a long-time span, the grade of satisfaction and safety of day-to-day 3D surgery compared to standard surgery and to investigate the technical distinctiveness between the heads-up systems currently in use. METHODS: In this retrospective observational case series. we reviewed all surgical records of our ophthalmology-dedicated operatory rooms since the arrival of 3D heads-up viewing system, in November 2017. In particular, we compared the procedural complications of 3D-equipped operatory room (3DR) with the standard microscope operatory room (2DR). Moreover, a satisfaction questionnaire was administered to those surgeons shifting on both rooms to test their preferences on seven specific parameters (comfort, visibility, image quality, depth perception, simplicity of use, maneuverability and teaching potential). RESULTS: 5483 eye surgeries were considered. 2777 (50.6%) were performed in 3DR and 2706 (49.3%) in 2DR. Procedural complication rate was comparable in 3DR and 2DR, also when considering different subtypes of surgery. Twelve surgeons (100% of our surgery team) participated in our satisfaction survey, expressing highest satisfaction score for 3D when applied in retina surgery. For cataract surgery, 3D scored best in all the parameters except for facility in use and depth of field perception. CONCLUSION: Long-term day-to-day use of 3D heads-up visualization systems showed its safety and its outstanding teaching potential in all ophthalmic surgical subtypes, with higher surgeons confidence for retina and cataract surgery.