Faculty Bibliography

PURPOSE: To describe anatomical relationships of retinal neovascular complexes (NVCs) and the posterior vitreous in proliferative diabetic retinopathy using spectral domain optical coherence tomography. METHODS: Cross-sectional study. Neovascular complexes were imaged using spectral domain optical coherence tomography in 51 eyes of 37 patients. The relationship of NVCs to the posterior vitreous cortex and posterior vitreous spaces, such as the premacular bursa, prevascular vitreous fissures, and perimacular cisterns, was analyzed. RESULTS: In the 77 NVCs evaluated, 61 (79%) had grown along the outer surface of the posterior hyaloid face, and vitreoschisis was present in 37 (48%). The "wolf's jaw" configuration was present in 9% and resulted from NVC arising from the arcades and proliferating along the posterior hyaloid face. By contrast, NVCs that invaded the bursa originated from smaller venous tributaries more distant from the arcades. The premacular bursa and prevascular vitreous fissure/perimacular cistern were invaded infrequently, respectively, in 15% and 38% (P = 0.137). CONCLUSION: Tomographic analysis of diabetic NVCs showed that most NVCs arise and grow along the posterior hyaloid face and that vitreoschisis is more prevalent than what has been found in ultrasound studies. The wolf's jaw configuration does not seem to result from the invasion of the bursa, as previously suggested.

PURPOSE: To describe a series of patients exhibiting annular retinal pigment epithelial (RPE) lesions in the context of chronic central serous chorioretinopathy. Design; Retrospective comparative case series. METHODS: Consecutive patients with chronic central serous chorioretinopathy were identified from the clinical practices of 3 retina specialists. A subset of patients exhibiting annular RPE lesions on fundus autofluorescence was included for chart review and examination of multimodal imaging (study group). Patients with alternative etiologies for neurosensory detachment or pigment epitheliopathy were excluded. A second consecutive cohort of patients, with acute central serous chorioretinopathy, was also examined for the presence of annular lesions (comparative group). RESULTS: Sixty-seven patients with chronic central serous chorioretinopathy were identified. Fourteen eyes of 12 patients exhibited annular lesions (study eyes). Mean visual acuity of study eyes was 20/27 (logMAR 0.13, SD 0.11). Annular lesions were composed of hyperautofluorescent stellate lesions arranged in an open or closed ring with intervening foci of punctate hypoautofluorescence. Optical coherence tomography showed RPE hyperplasia at the perimeters of annular lesions with loss of ellipsoid reflectivity and preserved RPE at the lesion center. Annular lesions were confined to the posterior poles and appeared to have developed at the margins of chronic neurosensory detachment. Forty-three eyes of 30 patients with acute central serous chorioretinopathy comprised the comparative group and none of these eyes exhibited annular lesions. CONCLUSIONS: Annular lesions occur in up to a fifth of patients with chronic central serous chorioretinopathy but carry a relatively good visual prognosis. Curvilinear RPE figures and demarcation lines are seen in various retinal conditions but the characteristics of annular lesions described here suggest that they are specific to chronic central serous chorioretinopathy.

PURPOSE: To evaluate the vascular structure of eyes with macular telangiectasia type 2 (MacTel2) using volume-rendered optical coherence tomography angiography (OCTA). DESIGN: Retrospective cross-sectional study. PARTICIPANTS: A total of 14 consecutive patients (20 eyes) with MacTel2 who had a signal strength score >/=55 and could maintain fixation during the scan process. METHODS: The eyes were scanned using optical coherence tomography with split-spectrum amplitude decorrelation techniques to derive flow information. Data were extracted and used to create volume-rendered images of the retinal vasculature that could be rotated about 3 different axes for evaluation. MAIN OUTCOME MEASURES: Descriptive appraisal of the vascular abnormalities associated with MacTel2. RESULTS: Vessels posterior to the outer boundary of the deep retinal plexus were secondary to retinal thinning, vascular invasion, or a combination of both. These vessels had the same shape and distribution as the late staining seen during conventional fluorescein angiography. Lateral contraction in the temporal macula in 5 eyes created an appearance of vessels radiating from a central locus, which was the site of a right angle vein. Loss of macular tissue as part of the disease process led to a central amalgamation of the inner vascular plexus and the deep vascular plexus, which appeared to be in a state of decline. Subretinal neovascularization originated from the retinal circulation but involved not only the subretinal space but also could infiltrate the remaining, thinned, retina. CONCLUSIONS: Volume rendering of OCTA information preserves the 3-dimensional relationships among retinal vascular layers and provides opportunities to visualize retinal vascular abnormalities in unprecedented detail. The retinal vascular leakage and invasion in MacTel2 may arise as a consequence of loss of control with depletion of Muller cells and exposure of the remaining retinal vessels to the more hypoxic environment near the inner segments of the photoreceptors.

Importance: The retinal vasculature is involved in many ocular diseases that cause visual loss. Although fluorescein angiography is the criterion standard for evaluating the retina vasculature, it has risks of adverse effects and known defects in imaging all the layers of the retinal vasculature. Optical coherence tomography (OCT) angiography can image vessels based on flow characteristics and may provide improved information. Objective: To investigate the ability of OCT angiography to image the vascular layers within the retina compared with conventional fluorescein angiography. Design, Setting, and Participants: In this study, performed from March 14, 2014, through June 24, 2014, a total of 5 consecutive, overlapping B-scan OCT angiography images composed of 216 A-scans were obtained at 216 discrete positions within a region of interest, typically a 2 x 2-mm area of the retina. The flow imaging was based on split-spectrum amplitude decorrelation angiography (SSADA), which can dissect layers of vessels in the retina. These distinct layers were compared with the fluorescein angiograms in 12 healthy eyes from patients at a private practice retina clinic to evaluate the ability to visualize the radial peripapillary capillary network. The proportion of the inner vs outer retinal vascular layers was estimated by 3 masked readers and compared with conventional fluorescein angiograms of the same eyes. Main Outcomes and Measures: Outcome measures were visualization of the radial peripapillary capillary network in the fluorescein and SSADA scans and the proportion of the inner retinal vascular plexus vs the outer retinal capillary plexus as seen in SSADA scans that would match the fluorescein angiogram. Results: In none of the 12 eyes could the radial peripapillary capillary network be visualized completely around the nerve head by fluorescein angiography, whereas the network was readily visualized in the SSADA scans. The fluorescein angiograms were matched, with a mean proportion of the inner vascular plexus being 95.3% (95% CI, 92.2%-97.8%) vs 4.7% (95% CI, 2.6%-5.7%) for the outer capillary plexus from the SSADA scans. Conclusions and Relevance: Fluorescein angiography does not image the radial peripapillary or the deep capillary networks well. However, OCT angiography can image all layers of the retinal vasculature without dye injection. Therefore, OCT angiography, and the findings generated, have the potential to affect clinical evaluation of the retina in healthy patients and patients with disease.

Importance: Macular telangiectasia type 2 (MacTel 2) is a rare disease in which abnormalities of the retinal vasculature play a key role. The vascular abnormalities are typically evaluated using fluorescein angiography, a modality with known defects in imaging the deeper layers of the retinal vasculature. Angiography based on optical coherence tomography can image vessels based on flow characteristics without dye injection and may provide improved information concerning the pathophysiology of MacTel 2. Objective: To investigate MacTel 2 using optical coherence tomographic angiography. Design, Setting, and Participants: Fourteen eyes of 7 patients with MacTel 2 were analyzed in a community-based retina practice. The flow imaging was based on split-spectrum amplitude decorrelation angiography, which can dissect layers of vessels in the retina. The inner retinal vascular plexus, the outer plexus, and deeper vascular invasion into the outer and subretinal spaces were optically dissected in en face images based on flow. Main Outcomes and Measures: Visualization and qualitative evaluation of the vascular layers of the retina as they may be affected by MacTel 2, both in terms of depth and topographic characteristics. Results: A consistent set of retinal vascular changes were seen in the eyes with MacTel 2. There was some loss of capillary density in the inner retinal vascular plexus but many more prominent alterations in the deep retinal vascular plexus. In milder forms of the disease, the deep plexus showed dilation and telangiectasis and, in more advanced cases, thinning and loss. The remaining vessels were elongated and widely spaced capillary segments. Invasion by new vessels into the outer and subretinal spaces occurred subjacent to the regions showing greatest flow imaging abnormalities in the inner and deep retinal vascular layers. Conclusions and Relevance: As evidenced by the patients in this study, important retinal vascular changes in MacTel 2 occur in the deep capillary plexus of the retina, a layer poorly visualized by fluorescein angiography and, to a lesser extent, in the inner vascular plexus. The proliferation of vessels in the outer and subretinal spaces may be in part compensatory for poor retinal perfusion by established vascular layers in the retina.

PURPOSE:: To assess for change in intraocular pressure (IOP) in neovascular age-related macular degeneration patients switched to aflibercept after receiving previous treatments of intravitreal bevacizumab or ranibizumab. METHODS:: This is a retrospective chart review of the first 53 patients (53 eyes) treated with at least 2 injections of 2 mg in 0.05 mL of aflibercept by March 6, 2013, after at least 2 previous injections of 0.5 mg in 0.05 mL of ranibizumab with or without previous injections of 1.25 mg in 0.05 mL of bevacizumab. The analysis was restricted to the first such sequence within each patient. The last previous anti-vascular endothelial growth factor injection before the switch to aflibercept was ranibizumab in all cases included in the study. Each person served as his or her own control. The pre-aflibercept IOP in the before state (treatment with bevacizumab or ranibizumab) was the preinjection IOP measure before dilation at the visit of the first aflibercept injection. Statistical analysis was performed using Microsoft Excel. RESULTS:: There were 41 patients who were first treated with ranibizumab followed by aflibercept and 12 patients treated with ranibizumab and bevacizumab followed by aflibercept. For each of these sequences, IOP in the treated eye during treatment with aflibercept (the after state) was computed in 3 different ways: the first IOP, the last IOP, and the mean IOP for the period when treated with aflibercept. The pooled data showed a mean pre-aflibercept (the before state) IOP of 14.87 that decreased to a mean first IOP of 14.57, mean last IOP of 13.79, and a mean IOP of 14.14 during aflibercept treatment. The inference is based on the pooled analysis. The 95% confidence interval for the differences (after minus before) were -0.30 (-1.12 to 0.52), -1.08 (-1.83 to -0.32), and -0.73 (-1.30 to -0.17) for the first, last, and mean IOPs, respectively. The corresponding P values were 0.46 for the first, 0.006 for the last, 0.01 for the mean IOP during the aflibercept treatment period. CONCLUSION:: Intraocular pressure was found to be significantly lower in patients switched to aflibercept after previous treatments with ranibizumab and/or bevacizumab. Aflibercept may have a more favorable IOP safety profile in patients previously on other anti-vascular endothelial growth factor treatments.

BACKGROUND AND OBJECTIVE: To assess the cone photoreceptor mosaic in acute macular neuroretinopathy (AMN) using adaptive optics (AO) imaging. PATIENTS AND METHODS: Four patients with AMN were evaluated retrospectively by near-infrared reflectance (IR) confocal scanning laser ophthalmoscopy (SLO), spectral-domain optical coherence tomography (SD-OCT), and a flood-illuminated retinal AO camera. Microperimetry was performed in one patient. RESULTS: The cone photoreceptor density was decreased at the level of the AMN lesions. The cone mosaic disruption appeared heterogeneous and more widespread than the lesion detected in the IR-SLO and SD-OCT images. The areas of cone loss correlated with SD-OCT and microperimetry. After resolution of the AMN lesion on IR-SLO, there was incomplete recovery of the cone photoreceptor mosaic. CONCLUSION: Cone photoreceptor damage and reconstitution were documented in vivo at the cellular level in AMN using AO imaging. AO imaging appeared more sensitive than combined IR-SLO and SD-OCT to detect and follow photoreceptor damage in patients with AMN. [Ophthalmic Surg Lasers Imaging Retina. 2014;45:562-569.].