Marco A. Bonini Filho

Spectral-Domain Optical Coherence Tomography Angiography of Choroidal Neovascularization

PURPOSE To describe the characteristics as well as the sensitivity and specificity of detection of choroidal neovascularization (CNV) on optical coherence tomography angiography (OCTA) using spectral-domain optical coherence tomography. DESIGN Observational, retrospective study. PARTICIPANTS Seventy-two eyes of 61 subjects (48 eyes of 43 subjects with CNV, 24 eyes of 18 subjects without CNV). METHODS Patients imaged using the prototype AngioVue OCTA system (Optovue, Inc, Fremont, CA) between August 2014 and October 2014 at New England Eye Center were assessed. Patients in whom CNV was identified on OCTA were evaluated to define characteristics of CNV on OCTA: size using greatest linear dimension (small, <1 mm; medium, 1-2 mm; large, >2 mm), appearance (well-circumscribed, poorly circumscribed), and presence of subretinal and intraretinal fluid. Concurrently, an overlapping second cohort of patients who underwent same-day OCTA and fluorescein angiography (FA) for suspected CNV was evaluated to estimate sensitivity and specificity of OCTA in detecting CNV using FA as ground truth. MAIN OUTCOME MEASURES Choroidal neovascularization appearance, CNV size, and presence of subretinal and intraretinal fluid. RESULTS In 48 eyes, CNV was visualized on OCTA. Thirty-one eyes had CNV associated with neovascular age-related macular degeneration. Size of CNV was small in 23% (7/31), medium in 42% (13/31), and large in 35% (11/31). Poorly circumscribed vessels, subretinal fluid, and intraretinal fluid each were seen in 71% (22/31). Seven eyes had CNV associated with central serous chorioretinopathy. Size of CNV was small in 71% (5/7) and large in 29% (2/7). Seventy-one percent (5/7) had well-circumscribed vessels, 86% (6/7) had subretinal fluid, and 14% (1/7) had intraretinal fluid. Thirty eyes with OCTA and same-day FA were evaluated to determine sensitivity and specificity of CNV detection on OCTA. Sensitivity was 50% (4/8) and specificity was 91% (20/22). CONCLUSIONS Using OCTA allows the clinician to visualize CNV noninvasively and may provide a method for identifying and guiding treatment of CNV. The specificity of CNV detection on OCTA compared with FA seems to be high. Future studies with larger sample sizes are needed to elaborate better on the sensitivity and specificity of CNV detection and to illustrate clinical usefulness.

Association of Choroidal Neovascularization and Central Serous Chorioretinopathy With Optical Coherence Tomography Angiography

IMPORTANCE Choroidal neovascularization (CNV) is a major cause of vision loss in chronic central serous chorioretinopathy (CSCR). Detecting CNV using fluorescein angiography (FA) may be challenging owing to the coexistence of features related to the primary diagnosis of CSCR. Optical coherence tomography angiography (OCTA) allows noninvasive visualization of retinal and choroidal vasculature via motion contrast and may contribute to the unequivocal diagnosis of CNV in this population. OBJECTIVE To evaluate the sensitivity of spectral-domain OCTA in detecting CNV associated with chronic CSCR. DESIGN, SETTING, AND PARTICIPANTS Observational cross-sectional study including 23 patients (27 eyes) who presented at the New England Eye Center between August 1, 2014, and November 30, 2014, with suspected CNV complicating chronic CSCR and underwent standard assessment for CNV diagnosis, including FA imaging. Participants were prospectively recruited to receive imaging tests using prototype OCTA software on a commercially available spectral-domain OCT. Orthogonal registration and the merging of 2 consecutive image sets were used to obtain 3 × 3-mm and 6 × 6-mm OCT angiograms centered at the macula. Two independent readers masked to other imaging findings performed a qualitative analysis on OCTA depictions of vascular flow representing CNV and the morphologic appearance of CNV. MAIN OUTCOMES AND MEASURES Choroidal neovascularization location as well as retinal pigment epithelial detachment internal reflectivity and the presence of subretinal and intraretinal fluid. Sensitivity and specificity of OCTA in detecting CNV were estimated using FA as the standard examination reference. RESULTS Choroidal neovascularization was diagnosed in 8 of 27 eyes (30%) based on FA imaging analysis. Optical coherence tomography angiography and corresponding OCT B-scans detected 100% (8 of 8) of these CNV lesions and correctly excluded 100% (19 of 19) of eyes with CSCR without CNV. Sensitivity was 100% (95% CI, 0.62-1) and specificity was 100% (95% CI, 0.82-1). Morphologic appearance, location, and position of the CNV relative to the retinal pigment epithelium and Bruch membrane were described using OCTA that combined flow and structural information. CONCLUSIONS AND RELEVANCE This study suggests that OCT alone (OCTA and coregistered OCT B-scans) features sensitivity and specificity comparable with FA for the detection of CNV in eyes with chronic CSCR.

OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY IN RETINAL ARTERY OCCLUSION.

Purpose: To describe the retinal microvasculature of the eyes with nonarteritic retinal artery occlusion (RAO) based on optical coherence tomography angiography. Methods: Cross-sectional, prospective, observational study performed from September 2014 through February 2015. En face projection of optical coherence tomography angiography images centered at the macula and optic disk of the eyes presenting with RAO were acquired using the RTVue XR Avanti with AngioVue software. Qualitative analysis of the morphology of the superficial and deep retinal capillary plexuses, and radial peripapillary capillaries was performed. Retinal vasculature images using optical coherence tomography angiography were correlated with fluorescein angiography images. Results: Seven patients (seven eyes) were enrolled in the study, including three eyes with central RAO and four eyes with branch RAO. Distinct differences in the distribution of zones of decreased vascular perfusion between the superficial and deep retinal capillary plexus corresponding to areas of delayed dye perfusion on fluorescein angiography were demonstrated in 6 of 7 (86.5%) eyes. Conclusion: This small series suggests that optical coherence tomography angiography imaging can accurately discern retinal capillary plexuses at different levels in the eyes with RAO and may be sensitive for more precisely characterizing the extent of macular ischemia and monitoring vascular flow changes during the course of the disease.

Retinal Capillary Network and Foveal Avascular Zone in Eyes with Vein Occlusion and Fellow Eyes Analyzed With Optical Coherence Tomography Angiography.

PURPOSE To evaluate the perifoveolar retinal capillary network at different depths and to quantify the foveal avascular zone (FAZ) in eyes with retinal vein occlusion (RVO) compared with their fellow eyes and healthy controls using spectral-domain optical coherence tomography angiography (SD-OCTA). METHODS We prospectively recruited 23 patients with RVO including 15 eyes with central RVO (CRVO) and 8 eyes with branch RVO (BRVO), their fellow eyes, and 8 age-matched healthy controls (8 eyes) for imaging on prototype OCTA software within RTVue-XR Avanti. The 3 × 3 mm and 6 × 6 mm en face angiograms of superficial and deep retinal capillary plexuses were segmented. Perifoveolar retinal capillary network was analyzed and FAZ was quantified. RESULTS Decrease in vascular perfusion at the deep plexus was observed in all eyes with CRVO (8/8, 100%) and BRVO (6/6, 100%) without cystoid macular edema, and in 8 of 15 (53%) and 2 of 8 (25%) of the fellow eyes, respectively. Vascular tortuosity was observed in 13 of 15 (87%) CRVO and 5 of 8 (63%) BRVO eyes. Collaterals were seen in 10 of 15 (67%) CRVO and 5 of 8 (63%) BRVO eyes. Mean FAZ area was larger in eyes with RVO than their fellow eyes (1.13 ± 0.25 mm2 versus 0.58 ± 0.28 mm2; P = 0.007) and controls (1.13 ± 0.25 mm2 versus 0.30 ± 0.09 mm2; P < 0.0001), and in fellow eyes of RVO patients when compared to controls (0.58 ± 0.28 mm2 versus 0.30 ± 0.09 mm2; P = 0.01). CONCLUSIONS Spectral-domain OCTA reveals abnormalities at different levels of perifoveolar retinal capillary network and is able to quantify the FAZ in RVO. Longitudinal studies may be considered to evaluate the clinical utility of OCTA in RVO and other retinal vascular diseases.

RETINAL AND CHOROIDAL VASCULATURE IN BIRDSHOT CHORIORETINOPATHY ANALYZED USING SPECTRAL DOMAIN OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

Purpose: To describe retinal and choroidal vascular changes in eyes with birdshot chorioretinopathy using optical coherence tomography angiography. Methods: Patients underwent imaging using the AngioVue prototype software of the RTVue XR spectral domain optical coherence tomography device (Optovue, Inc) between September and December 2014. Two trained patients evaluated the optical coherence tomography angiography images for changes in the retinal and choroidal vasculature in the posterior pole. Results: Four of eight eyes (50%) had birdshot lesions in the posterior pole as demonstrated on fundus photography. All of these eyes demonstrated the areas of decreased choroidal blood flow below the disrupted retinal pigment epithelium. Larger choroidal vessels bordered the birdshot lesions. All eyes analyzed showed retinal thinning, telangiectatic vessels, and an increased intercapillary space. Capillary dilatations and loops were each seen in 7 of 8 eyes (88%). Conclusion: Optical coherence tomography angiography provides precise microvascular detail of the retinal vasculature and choriocapillaris that allows for the noninvasive visualization of the birdshot lesions and changes in the inner retina. The optical coherence tomography angiography images delineated widespread retinal vascular findings not previously described in the literature. In the future, optical coherence tomography angiography could be a useful tool to evaluate the natural history of birdshot chorioretinopathy, its progression, and the effect of treatment in these patients.

Optical Coherence Tomography Angiography for Detecting Choroidal Neovascularization Secondary to Choroidal Osteoma

Choroidal osteoma is an ossifying tumor that is found predominantly in the peripapillary and macular areas. It typically affects otherwise healthy females. Vision loss may occur secondary to the development of choroidal neovascularization (CNV). Fluorescein angiography (FA) remains the gold standard for diagnosing CNV; however, the use of optical coherence tomography angiography (OCTA) as an adjunct to FA is growing. In this report, a 16-year-old female with a large, unilateral peripapillary choroidal osteoma presented with blurred vision. Exam revealed scattered intraretinal hemorrhage, but FA was unable to detect CNV overlying the tumor. OCTA detected abnormal flow in the outer retina corresponding to a type 2 CNV. Following intravitreal anti-vascular endothelial growth factor therapy, the CNV regressed, the hemorrhage resolved, and there was less fluid. OCTA may be helpful in detecting CNV noninvasively in eyes in which FA is equivocal, such as those with choroidal osteoma.

Optical Coherence Tomography Angiography of Chorioretinal Diseases.

Fluorescein angiography (FA) and indocyanine green angiography (ICGA) have been the gold standard for the evaluation of retinal and choroidal vasculature in the last three decades and have revolutionized the diagnosis of retinal and choroidal vascular diseases. The advantage of these imaging modalities lies in their ability to document retinal and choroidal vasculature through the dynamic assessment of contrast transit over time in the intravascular and extravascular spaces. However, disadvantages include the absence of depth resolution, blurring of details by contrast leakage, and the inability to selectively evaluate different levels of the retinal and choroidal microvasculature. In addition, these angiographic methods require intravenous dye, which may cause adverse reactions such as nausea, vomiting, and rarely, anaphylaxis. Optical coherence tomography angiography (OCTA) is a noninvasive imaging technique that, in contrast to dye-based angiography, is faster and depth-resolved, allowing in some cases for more precise evaluation of the vascular plexuses of the retina and choroid. The method has been demonstrated in the assessment of various vascular diseases such as venous occlusions, diabetic retinopathy, macular neovascularization, and others. Limitations of this imaging modality include a small registered field of view and the inability to visualize leakage and dye transit over time. It is also subject to a variety of artifacts, including those generated by blinking and eye movement during image acquisition. However, more than an alternative for FA and ICGA, OCTA is bringing new insights to our understanding of retinal and choroidal vascular structure and is changing fundamental paradigms in the clinical management of pathologic conditions. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:848-861.].