Clinical Applications of Optical Coherence Tomography and Optical Coherence Tomography Angiography in Uveal Melanoma: A Narrative Review

To determine the microvascular changes of the retina and choroid in sickle cell anemia (SCA) patients and to investigate the relationship between the severity of sickle cell retinopathy and sickle cell maculopathy (SCM). In this cross-sectional study, 78 eyes of 39 patients with SCA were included in the patient group and 68 eyes of 34 healthy participants were included in the control group. Differences in foveal avascular zone (FAZ), retinal and subfoveal choroidal thickness (SFCT), and choroidal vascularity index (CVI) between the patient group and the control group were evaluated by swept source optical coherence tomography (OCT) and OCT angiography (OCTA) imaging. In addition, systemic and biological parameters were compared in patients with and without SCM. SCM was detected in 16 eyes of 8 patients. Proliferative sickle cell retinopathy (PSCR) was present in 10 patients. In logistic regression analysis, PSCR was found to be a risk factor for the development of SCM (p=0.015, odds ratio: 17.25, 95% confidence interval: 1.73-172.02). The temporal inner retinal layers were significantly thinner in the patient group compared to the control group. The patient group also exhibited significantly greater FAZ enlargement in both the superficial and deep capillary plexus when compared with the control group (p<0.001 for both). CVI was higher in the control group than in the patient group (p<0.001). SFCT was significantly thinner in the patient group (p=0.013). There was no significant difference between patients with and without SCM in terms of FAZ enlargement, CVI values, or systemic and biological factors. In our study, PSCR was found to be a risk factor for the development of SCM. OCT and OCTA provide valuable information about microvascular changes in the retina and choroid in patients with SCM. Structural changes demonstrated by OCTA before the development of SCM are very important for follow-up and treatment in terms of visual prognosis of patients.

Comparison of Gonioscopy and Anterior Segment Ocular Coherence Tomography in Detecting Angle Closure in Different Quadrants of the Anterior Chamber Angle

Spectral-Domain Optical Coherence Tomography Angiography of Choroidal Neovascularization

To describe the imaging features of choroidal nevus and melanoma using optical coherence tomography angiography, and evaluate the ability of this technique to establish the differential diagnosis based on the display of the tumor's intrinsic vasculature. Comparative analysis of optical coherence tomography angiography findings in consecutive patients diagnosed with choroidal nevus or choroidal melanoma following a complete ophthalmic evaluation, including best-corrected visual acuity and several imaging studies: color fundus photography, B-scan ultrasound, spectral-domain optical coherence tomography, and optical coherence tomography angiography. Optical coherence tomography angiography was used to investigate qualitative differences in the tumor vasculature. Thirty-six eyes (18 cases of choroidal nevus and 18 cases of choroidal melanoma) from 36 consecutive patients were included in the study. Only cases located posterior to equator were included to enable performance of all tests. On optical coherence tomography angiography, choroidal nevus showed well-delimited margins (78%), hyperreflective choroid capillary vasculature (83%), fewer avascular areas (17%), and neovascular membrane in one case (6%). Choroidal melanoma showed imprecise margins (72%), hyporeflective choroidal capillary vasculature (72%), multiple avascular areas (78%), and choroidal vascular changes (e.g. thick vascular networks or vascular loops; 45%). Optical coherence tomography angiography can provide useful information for assessing and differentiating between choroidal nevi and small melanomas. Significant differences between these conditions were found for the pattern of reflectivity, and presence/absence of avascular zones and vascular anomalies, which could be helpful for supporting the diagnosis.

Recent decade has seen a shift in the causes of childhood blinding diseases from anterior segment to retinal disease in both developed and developing countries. The common retinal disorders are retinopathy of prematurity and vitreoretinal infections in neonates, congenital anomalies in infants, and vascular retinopathies including type 1 diabetes, tumors, and inherited retinal diseases in children (up to 12 years). Retinal imaging helps in diagnosis, management, follow up and prognostication in all these disorders. These imaging modalities include fundus photography, fluorescein angiography, ultrasonography, retinal vascular and structural studies, and electrodiagnosis. Over the decades there has been tremendous advances both in design (compact, multifunctional, tele-consult capable) and technology (wide- and ultra-wide field and noninvasive retinal angiography). These new advances have application in most of the pediatric retinal diseases though at most times the designs of new devices have remained confined to use in adults. Poor patient cooperation and insufficient attention span in children demand careful crafting of the devices. The newer attempts of hand-held retinal diagnostic devices are welcome additions in this direction. While much has been done, there is still much to do in the coming years. One of the compelling and immediate needs is the pediatric version of optical coherence tomography angiography. These needs and demands would increase many folds in future. A sound policy could be the simultaneous development of adult and pediatric version of all ophthalmic diagnostic devices, coupled with capacity building of trained medical personnel.

We evaluated the structural and functional features of combined hamartoma of the retina and retinal pigment epithelium using multimodal imaging technologies, including the new technique of optical coherence tomography (OCT) angiography, which has previously not been used to examine this rare condition. Nine eyes of nine Caucasian patients (median age at presentation: 8 years; range: 1−36 years) were evaluated in the Eye Clinic of the University of Naples ‘Federico II’ between September 2014 and February 2015. Patients underwent complete ophthalmic examination, bulbar echography, enhanced depth imaging optical coherence tomography (EDI-OCT), wide-field en-face OCT, multicolour imaging, fluorescein and indocyanine angiography and OCT angiography. The mean best-corrected visual acuity was 20/40 ± 4.2 Snellen. At standardized A-scan echography, the mean tumour basal dimension was 3 mm. All tumours were in the temporal quadrant, and seven affected the left eye. The OCT findings revealed a mean foveal retinal thickness of 522 ± 248 (mean ± standard deviation) μm in affected eyes versus 226 ± 22 μm in unaffected eyes. The mean retinal thickness through the tumour epicentre in affected and unaffected eyes was 809 ± 269 μm and 361 ± 44 μm, respectively. The mean tumour thickness was 752 μm. On EDI-OCT, the mean choroidal thickness below the tumour epicentre was significantly less in affected eyes than the mean choroidal thickness in unaffected eyes (251 ± 50 μm versus 388 ± 38 μm). Both intraretinal and subretinal fluid was present in two affected eyes, intraretinal fluid alone in three affected eyes, retinal striae overlying the tumour in two eyes and retinal schisis in two eyes. Based on multicolour images, hamartomas were classified green or grey, indicating more or less abundant tissue, respectively. En-face OCT revealed an epiretinal membrane and vitreoretinal traction in all patients. Fluorescein and indocyanine angiography in the early phase showed such vascular irregularities as dilation or vascular tortuosity which were not visible in the later phase due to leakage. However, at OCT angiography, vascular irregularities were clearly seen in the tumoral area. Moreover, OCT angiography showed that the main superficial retinal vessels lose most of their collateral branches and present many loops; capillaries were rare and there were anomalies in vessel size. At deep plexus level, changes in vessel size and morphology were evident and the capillary fans were irregular. No functional or anatomic changes versus baseline were identified at the 24-month follow-up observation, except in a 21-year-old man in whom visual acuity decreased. As shown in Fig. 1, multicolour imaging at follow-up in this patient revealed retinal haemorrhage and increased retinal traction. A-scan echography and OCT showed an increase in the size of the tumour base, retinal thickness and retinal traction, which can cause retinal haemorrhage. Optical coherence tomography angiography revealed vessel stretching and a slight reduction in anastomosis. In this patient, the hamartoma slowly increased in size thereby causing shrinkage of the internal membrane of the tumour, which in turn leads to deformation of the retinal vessels as they are attracted towards the centre of the neoplasm (Mele et al. 1984). Surgery in the management of combined hamartoma remains controversial (Bruè et al. 2013). In fact, the surface glial membrane causing the retinal distortion is often an integral part of the tumour, which can mean that is difficult or impossible to strip the membrane and that there is little chance of central vision (Chhablani et al. 2015). In conclusion, our results indicate that the new OCT angiography technique is a non-invasive, reliable method with which to evaluate vascular irregularities in the tumour area without the injection of any dye. Consequently, OCT angiography is an ideal procedure with which to evaluate this condition in young patients.

To describe the optical coherence tomography (OCT) angiography (OCTA) features of diabetic retinopathy. Retrospective serial case reports were examined of patients who underwent routine clinical examination and OCTA with both DRI OCT Atlantis prototype and Triton Swept-Source OCT of the posterior pole and mid-periphery. When considered necessary, fluorescein fundus angiography (FFA) with OPTOS California wide-field imaging was performed. The findings were compared with the current literature. Forty-three consecutive patients (86 eyes) were evaluated. Fourteen of these patients (28 eyes) underwent an additional FFA examination due to advanced retinopathy signs, such as diabetic macular edema, ischemia or neovascularization (NV). OCTA was able to detect the microvascular lesions observed on color fundus images in the whole sample. Thirty-six of the 86 eyes showed foveal avascular zone enlargement on OCTA. Microvascular lesions, diabetic macular edema, and NV of the optic disc observed on FFA were also detected on OCTA in all cases (28/28 eyes). Features of NV elsewhere were detected on FFA in 16/28 eyes. Ten of the 16 eyes had signs of NV within the 100 central degrees, and OCTA was able to detect these signs in 9 of the eyes. OCTA is an effective noninvasive imaging technique that can provide additional information regarding the localization and morphology of vascular lesions in all cases of NV of the optic disc and in more than half of cases of NV elsewhere, suggesting that it is a noninferior technique for the study of posterior pole alterations compared with FFA, which remains the gold standard and is fundamental for the study of the retinal periphery.

Choroidal osteoma (CO), also known as osseous choristoma, is a rare benign osseous tumour of the choroid. It is diagnosed based on the presence of a yellowish-white to orange lesion deep in the retinal pigment epithelium (RPE) with well-defined margins and bone density in ultrasonography (Pellegrini et al. 2014). Patients are usually asymptomatic and the lesion is found incidentally. Choroidal neovascularization (CNV) is the most frequent complication of CO and leads to severe visual impairment. Anti-vascular endothelial growth factor (Anti-VEGF) therapy has been recommended for CNV-related CO (Song & Roh 2009). Here, we report a case of extrafoveal CO associated with CNV. A 75-year-old woman, incidentally diagnosed with CO at the age of 68 years, presented with a two-month history of metamorphopsia in the left eye. Best-corrected visual acuity (BCVA) was 0 logMar in the right eye and 0.7 logMar in the left eye. Anterior segment findings were unremarkable in both eyes. A fundus examination of the right eye was unremarkable, whereas, in the left eye, it revealed a yellowish-white area with small haemorrhages in the superior temporal retina that suggested an extrafoveal CO associated with CNV (Fig. 1A,B). Baseline evaluation of the right eye. (A, B) Colour fundus photography and multicolour image showing the choroidal osteoma with subretinal haemorrhage. The black circle underlines macular haemorrhage spots. (C−E) Optical coherence tomography (OCT) angiography, fluorescein angiography and indocyanine green angiography revealed late-stage choroidal neovascularization within the tumour. The red circle underlines macular haemorrhage spots (F, G) A and B scan echography showed a slightly elevated choroidal mass with high reflectivity and acoustic shadowing. (H) Enhanced depth imaging optical coherence tomography (EDI-OCT) showed a hyper-reflective mass in the subretinal space associated with a neurosensory detachment and detected a sponge-like structure of the choroid. (I, J) Fluorescein and indocyanine angiography of the superotemporal region of the contralateral normal eye. (K) Optical coherence tomography (OCT) scan of the macular region without any pathological feature. (L−P) Colour fundus photography, multicolour image, fluorescein angiography and indocyanine green angiography and OCT angiography showing regression of the choroidal neovascularization after four months of treatment. (Q) Enhanced depth imaging optical coherence tomography (EDI-OCT) revealed resolution of the subretinal fluid. [Correction added on 17 June 2016 after first online publication: Figure 1 has been replaced to correct the labelling of Fig. 1E and 1O]. Optical coherence tomography (OCT) angiography (angiovue software RTVue; Optovue Inc., Fremont, CA, USA) showed a hyporeflective area surrounded by a hyper-reflective-edged ring in direct relation to the osteoma. It also showed a dense irregular vascular network within the tumour in the outer retinal layer and choroid capillary layers. Moreover, the CNV detected in the choroidal layer had fine glomerular-like hyper-reflection (Fig. 1C). Visualization of vessels is better with non-invasive OCT angiography than with fluorescein angiography (FA) and Indocyanine green angiography (ICGA); in fact, with the latter two techniques, the leaking vessels of the CNV usually are overshadowed by the dye in the late phases (Wang et al. 2015). Fluorescein angiography (FA) showed early hyperfluorescence due to leakage surrounded by an area of blocked fluorescence, and late staining of the lesion showed well-defined borders (Fig. 1D). Indocyanine green angiography (ICGA) confirmed the presence of an active CNV secondary to CO (Fig. 1E). Standardized A and B scan echography revealed a slightly elevated choroidal mass with high reflectivity and acoustic shadowing (Fig. 1F,G). Enhanced depth imaging optical coherence tomography (EDI-OCT) performed with the Heidelberg Spectralis HRA + OCT (Heidelberg Engineering, Heidelberg, Germany) showed a hyper-reflective mass in the subretinal space associated with neurosensory detachment and elongation of the outer segments. Enhanced depth imaging optical coherence tomography (EDI-OCT) also revealed a sponge-like structure of the choroid with horizontal tubules (Fig. 1H). The findings obtained in our patient strongly support the diagnosis of OC as opposed to sclerochroidal calcification (SCC). In fact, unlike OC, SCC does not feature growth, decalcification or intralesional vessels of CNV, as recently reported by Shields et al. (2015). After obtaining informed consent, we administered three monthly intravitreal injections of ranibizumab in the left eye. Four months later, the patient's BCVA was 0.1 logMar, and a fundus examination revealed resolution of the subretinal haemorrhage (Fig. 1L,M). Fluorescein angiography (FA) and ICGA showed regression of the CNV (Fig. 1N,O) and spectral domain OCT revealed no subretinal fluid (Fig. 1Q). Optical coherence tomography (OCT) angiography demonstrated a smaller and more rarified vascular network inside a capsular formation (Fig. 1P). These findings remained unchanged during the 12-month follow-up. In summary, OCT angiography reveals unique features in the vascular changes of CNV in CO not visualized with other imaging methods. However, additional studies are needed to verify whether this technique can partially replace FA and ICGA in the diagnosis and follow-up of CNV secondary to CO.

Due to the general aging of society, the prevalence and incidence of dementia are expected to increase considerably. In order to timely identify patients and assess their need for treatment and/or supportive measures, comprehensive and easy access screening methods are required, which, however, are yet to be developed. To date, several biomarkers for the presence of dementia on high-resolution spectral domain optical coherence tomography (OCT) and OCT angiography (OCT-A) images were identified. To summarize previously identified OCT biomarkers in dementia and to assess their suitability for comprehensive screening examinations. Aliterature search was conducted on PubMed until March 2023 for the keywords "dementia", "mild cognitive impairment", "OCT", "OCT angiography" and "retinal biomarkers". Relevant publications were identified and summarized. Numerous unspecific alterations on OCT imaging and OCT‑A were identified in patients with (predementia) dementia according to many population and clinical studies. These include areduced thickness of the peripapillary retinal nerve fiber layer, the ganglion cell complex and the central retinal region. Additionally, areduced vascular density and an enlarged foveal avascular zone (FAZ) were identified on OCT‑A imaging. The currently known OCT biomarkers are too unspecific, and there is to date no OCT or OCT-A-based signature distinguishing between different types of dementia. Further longitudinal studies with larger sample sizes are warranted to develop and evaluate such distinct OCT signatures for different types of dementia and their respective early disease stages and to assess their prognostic value. Only then is the inclusion in comprehensive screening investigations feasible.

SynopsisIn optical coherence tomography angiography, the choroidal vascular flow rate in choroidal melanoma is significantly lower than that in choroidal nevus.ObjectiveThe objective of this study was to describe the choriocapillaris and retinal features imaged by optical coherence tomography angiography (OCTA) in eyes with choroidal nevus from small malignant choroidal melanoma.MethodsIn this retrospective, noninvasive, observational study, 11 patients diagnosed with small choroidal mass (five with choroidal nevus and six with malignant melanoma) who underwent dilated fundus examination, ocular ultrasonography and OCTA images were compared.ResultsIn choroidal nevus of all patients, OCTA demonstrated a hyporeflective mass with no significant deformity of choroidal vasculature and an intact retinal pigment epithelium (RPE)–Bruch’s membrane complex. The flow void mass was surrounded by an intense vascular rim named as surface microvasculature (SMV) that had an approximately similar flow rate median of 63.68 mm2 (60.42–67.62 mm2), comparable with the median of the contralateral normal eye of 61.77 mm2 (60.42–64.53 mm2; P>0.09) for nevi. OCTA showed an obscured Bruch’s membrane–RPE–Bruch’s membrane complex and outer retinal layer in choroidal melanomas. Choriocapillaris flow rate over the melanomas was 55.73% (41.93%–60.82%), and the corresponding normal areas had a flow area of 62.75% (61.99%–63.10%; P=0.01). A flow rate difference between choroidal melanoma and nevus was significant (P=0.006). Axial and peripheral feeding vessels were more dilated and tortuous compared with benign nevi.ConclusionDecreased flow rate of SMV of choroidal melanoma cases compared with nevi was a significant finding. Detection of characteristic vascular features of choroidal melanoma by OCTA could make OCTA an assuring diagnostic modality to differentiate malignant lesions.

To investigate the utility of ultrahigh speed, swept source optical coherence tomography angiography in visualizing retinal microvascular and choriocapillaris (CC) changes in diabetic patients. The study was prospective and cross-sectional. A 1,050 nm wavelength, 400 kHz A-scan rate swept source optical coherence tomography prototype was used to perform volumetric optical coherence tomography angiography of the retinal and CC vasculatures in diabetic patients and normal subjects. Sixty-three eyes from 32 normal subjects, 9 eyes from 7 patients with proliferative diabetic retinopathy, 29 eyes from 16 patients with nonproliferative diabetic retinopathy, and 51 eyes from 28 diabetic patients without retinopathy were imaged. Retinal and CC microvascular abnormalities were observed in all stages of diabetic retinopathy. In nonproliferative diabetic retinopathy and proliferative diabetic retinopathy, optical coherence tomography angiography visualized a variety of vascular abnormalities, including clustered capillaries, dilated capillary segments, tortuous capillaries, regions of capillary dropout, reduced capillary density, abnormal capillary loops, and foveal avascular zone enlargement. In proliferative diabetic retinopathy, retinal neovascularization above the inner limiting membrane was visualized. Regions of CC flow impairment in patients with proliferative diabetic retinopathy and nonproliferative diabetic retinopathy were also observed. In 18 of the 51 of eyes from diabetic patients without retinopathy, retinal mircrovascular abnormalities were observed and CC flow impairment was found in 24 of the 51 diabetic eyes without retinopathy. The ability of optical coherence tomography angiography to visualize retinal and CC microvascular abnormalities suggests it may be a useful tool for understanding pathogenesis, evaluating treatment response, and earlier detection of vascular abnormalities in patients with diabetes.

Purpose: To investigate retinal and choroidal microvascular changes and structural choroidal involvement in retinal vein occlusion (RVO). Methods: Retrospective analysis of treatment-naïve macular edema secondary to RVO, studied by optical coherence tomography (OCT) and OCT angiography (OCTA), before and after the loading phase of intravitreal injections of ranibizumab (IVR-LP). OCTA was performed using two different devices: AngioVue RTVue XR Avanti (spectral-domain OCTA) and Zeiss PLEX® Elite 9000 (swept-source OCTA). Results: 30 eyes of 30 consecutive patients (17 branch and 13 central RVO) were included. Central macular thickness and subfoveal choroidal thickness (SCT) were significantly reduced after IVR-LP (p < 0.001 and p = 0.046, respectively). 23 eyes were eligible for OCTA analysis. Baseline vessel density (VD) in deep capillary plexus (DCP) was significantly reduced in RVO eyes compared with fellow eyes (p = 0.03 and p = 0.002 for PLEX® Elite and AngioVue, respectively). After IVR-LP, no significant VD changes in any vascular layer was found. PLEX® Elite VD analysis showed significant differences in DCP between ischemic versus non-is­chemic eyes (p = 0.011). Conclusion: OCTA suggests a retinal vascular impairment of DCP but no involvement of choroid in RVO eyes. A greater baseline SCT could be due to a choroidal exudation. OCTA imaged with PLEX® Elite allowed to differentiate ischemic and non-ischemic patients at baseline.

We analyzed and compared the sensitivity of choroidal neovascularization (CNV) detection according to CNV type in patients with active neovascular age-related macular degeneration (AMD) using swept-source optical coherence tomography (OCT) angiography (OCTA). A retrospective chart review was performed in patients with neovascular AMD. OCTA images were classified into three groups: Group A (well-circumscribed vascular complex); Group B (moderately circumscribed vascular complex); and Group C (poorly circumscribed vascular complex), according to CNV appearance. Demographic characteristics, OCT parameters, neovascularization subtypes, and OCTA image quality were analyzed to determine the effect on visualization of the neovascular complex. A total of 130 patients with CNV secondary to active neovascular AMD were analyzed. Among them, 52 eyes from 47 patients were included in the study. Eighteen eyes (34.6%) were classified into Group A, 24 (46.2%) into Group B, and 10 (19.2%) into Group C. Statistical analysis showed no significant differences in demographic characteristics or OCT parameters between the three groups. Overall sensitivity of active CNV detection was 80.7% (42/52 eyes). In 73.5% (25/34) of eyes with type 1 CNV (sub-retinal pigment epithelial type), 100.0% (9/9) of eyes with type 2 CNV (sub-retinal type), and 88.9% (8/9) of eyes with type 3 CNV (retinal angiomatous proliferation type), the vascular complex was well visualized on OCTA. OCTA provides adequate noninvasive imaging of CNV in patients with neovascular AMD, which may assist in CNV diagnosis and activity monitoring. In particular, type 2 CNV was well detected in OCTA in comparison with type 1 and type 3 CNV.

To evaluate, in eyes with radiation maculopathy, the effect of 2-month-interval anti-vascular endothelial growth factor therapy on best-corrected visual acuity and foveal avascular zone (FAZ) enlargement using optical coherence tomography angiography. Consecutive treatment-naive patients with radiation maculopathy after proton beam irradiation for choroidal melanoma were retrospectively included. Clinical and optical coherence tomography angiography data at baseline and the 6-month visit were recorded. Two independent observers measured FAZ area manually on 3 × 3-mm optical coherence tomography angiography images of the superficial capillary plexus and deep capillary plexus. Patients were encouraged to follow strictly a 2-month-interval intravitreal anti-vascular endothelial growth factor treatment by either bevacizumab or ranibizumab. Findings were analyzed based on the adherence to the treatment scheme. According to the adherence to the bimonthly anti-vascular endothelial growth factor treatment protocol, patients were categorized into 3 groups: treatment protocol (n = 19, strict adherence), variable intervals (n = 11, intervals other than 2 months), and no treatment (n = 11). The estimated radiation dose to the foveola in each group was 49 ± 16, 46 ± 17, and 46 ± 18 cobalt gray equivalent, respectively (P = 0.85). For the entire cohort, best-corrected visual acuity loss (P < 0.02) and FAZ enlargement (P < 0.0001) were observed over 6 months. Best-corrected visual acuity loss was significantly less pronounced in the treatment-protocol group than in the variable-interval and no-treatment groups (P = 0.007 and P = 0.004). The FAZ enlargement was lower in the treatment-protocol group compared with the variable-interval group for both superficial capillary plexus (P = 0.029) and deep capillary plexus (P = 0.03), and to the no-treatment group for the deep capillary plexus only (P = 0.016). Decrease in best-corrected visual acuity and FAZ enlargement on optical coherence tomography angiography occurred over 6 months in eyes with radiation maculopathy and were significantly reduced under 2-month-interval anti-vascular endothelial growth factor therapy.

Objective To observe the difference of macular microvascular features in superficial and deep vascular plexi in patients with branch retinal vein occlusion (BRVO). Methods A total of 63 BRVO patients (63 eyes) were enrolled in this study. There were 28 males (28 eyes) and 35 females (35 eyes). The patients aged from 39 to 74 years, with the mean age of (59.76±8.48) years. All eyes were evaluated by optical coherence tomography angiography (OCTA). The macular angiography scan protocol covered a 3 mm×3 mm area. The focus of angiography analysis included superficial vascular plexus and deep vascular plexus. The following vascular morphological parameters were assessed in these two plexi: foveal avascular zone (FAZ) enlargement, capillary non-perfusion (CNP) occurrence, microvascular abnormalities (MA) appearance, and vascular congestion (VC) signs. The FAZ area was measured by the built-in software. The macular microvascular morphology changes in superficial and deep vascular plexi were compared through McNemar test. Results The superficial and deep plexi showed FAZ enlargement in 43 eyes (68.3%) and 50 eyes (79.4%), CNP in 51 eyes (81%) and 50 eyes (79.4%), MA in 62 eyes (98.4%) and 62 eyes (98.4%), VC in 23 eyes (36.5%) and 52 eyes (82.5%), respectively. FAZ area was (0.55±0.37) mm2. There was no difference in CNP (P=1.000) and MA (P=1.000) between superficial and deep plexi. But, there was difference in FAZ enlargement (P=0.039) and VC signs (P<0.001) between superficial and deep plexi. Conclusion Deep vascular plexus showed more FAZ enlargement and VC sign than superficial plexus in BRVO patients. Key words: Retinal vein occlusion/diagnosis; Tomography, optical coherence