Alessandro Marchese

Choroid morphometric analysis in non-neovascular age-related macular degeneration by means of optical coherence tomography angiography

Aims To describe the vascular changes in patients affected by non-neovascular age-related macular degeneration (AMD), featuring reticular pseudodrusen (RPD), drusen, or both RPD and drusen by means of optical coherence tomography angiography (OCT-A). Methods Cross-sectional observational case series. Patients with non-neovascular AMD presenting at the Medical Retina Service of the Department of Ophthalmology, University Vita-Salute San Raffaele in Milan were recruited. Patients underwent best-corrected visual acuity, biomicroscopy, infrared reflectance, short-wavelength fundus autofluorescence and OCT-A (AngioPlex, CIRRUS HD-OCT 5000, Carl Zeiss Meditech, Dublin, USA). Main outcome was quantification of vessel density, stromal tissue, and vascular/stromal (V/S) ratio at the choriocapillaris (CC), the Sattler and Hallers and the whole choroid layers among different groups of patients with non-neovascular AMD by means of binarised OCT-A scans. Results 45 eyes of 34 patients were enrolled (15 eyes of 11 patients with RPD, group 1; 15 eyes of 11 patients with drusen, group 2; 15 eyes of 12 patients with mixed phenotype, group 3). The CC, the Sattler and Hallers and the whole choroid vessel density were reduced in all groups of patients (p=0.023, p=0.007 and p=0.011 in group 1, group 2 and group 3 for the CC; p=0.021, p=0.037 and p=0.043 in group 1, group 2 and group 3 for the Sattler and Hallers density; p=0.016, p=0.002 and p<0.001 in group 1, group 2 and group 3 for the choroidal density), with significantly lower V/S ratios compared with healthy controls. Conclusions Patients with non-neovascular AMD show significant choroidal vascular depletion and fibrotic replacement, suggesting a possible role in the pathogenesis and progression of the disease.

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 (r2 = 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.

Multimodal retinal imaging in central serous chorioretinopathy treated with oral eplerenone or photodynamic therapy

PurposeTo correlate function and structural optical coherence tomography (OCT) to optical coherence tomography angiography (OCT-A) measures in patients affected by central serous chorioretinopathy (CSC) and to describe their changes after treatments (ie oral eplerenone, half-fluence photodynamic therapy (PDT)).Patients and methodsTwenty eyes of 16 consecutive patients with treatment-naïve CSC undergoing either eplerenone or PDT were enrolled in this prospective, observational study. All patients underwent structural OCT and OCT-A at baseline and after therapy at months 1 and 3.ResultsEleven eyes of nine patients and nine eyes of seven patients underwent eplerenone or PDT treatment, respectively. Central macular thickness (CMT) and subretinal fluid (SRF) correlated to fovea avascular zone (FAZ) area (r=0.74 and r=0.71, P=0.01) and vessel density (r=0.77 and r=0.68, P=0.01) at deep capillary plexus (DCP). CMT (P=0.0011), SRF (P=0.0005), SFCT (P=0.0016), FAZ area at DCP (P=0.0334) improved at 3-month visit. A significant reduction of deep FAZ area was appreciated in eplerenone (P=0.0204) but not in PDT (P=0.5) group. SFCT reduction was significantly higher in PDT than eplerenone group (P=0.0347).ConclusionStructural and vascular parameters are correlated in CSC and they improve after different treatments. Both half-fluence PDT and oral eplerenone do not permanently damage choriocapillaris or other choroidal layers as evaluated by OCT-A.

Macular perfusion parameters in different angiocube sizes: does the size matter in quantitative optical coherence tomography angiography?

Purpose To investigate the macular quantitative parameters interchangeability of three different optical coherence tomography angiography (OCT-A) angiocubes (i.e., 3 × 3, 6 × 6, and 12 × 12 mm) on healthy subjects and patients affected by diabetic retinopathy (DR) and to assess the interrater reliability of such indices across the different scan protocols. Methods Retrospective study involving 20 eyes of healthy subjects and 20 eyes with DR. All eyes underwent swept-source OCT-A with 3 × 3-, 6 × 6-, and 12 × 12-mm angiocubes centered on the fovea. Foveal avascular zone (FAZ) area and vessel density on 3 × 3-, 6 × 6-, and 12 × 12-mm macular scans were calculated by three independent operators at all retina, superficial, deep, and choriocapillary vascular layers. Interchangeability and interrater reliabilities were estimated using intraclass correlation coefficient (ICC). Results Interscan reproducibility of FAZ area was very strong (ICC > 0.85) at every plexus. On the contrary, vessel density values significantly varied across different scan sizes (ICC < 0.51). Intrascan interrater reliability was high for all retina and superficial FAZ areas, while it was satisfactory at deep capillary plexus only for 3 × 3-mm scan. Conclusions FAZ area at all plexuses is a robust parameter even if calculated on angiocubes with different size. However, interrater reliability is higher when measured in smaller scans. Conversely, vessel density results depend on the size of angiocube, although their interrater reliability is extremely high. Studies involving OCT-A should take into consideration that scan size may influence macular perfusion parameters and interrater reliability.

The Evolution of the Plateau, an Optical Coherence Tomography Signature Seen in Geographic Atrophy

We read with interest the article by Tan et al. entitled ‘‘The Evolution of the Plateau, an Optical Coherence Tomography Signature Seen in Geographic Atrophy.’’ We congratulate the authors for the excellent description of the origins and long-term evolution of an optical coherence tomography (OCT) feature named ‘‘plateau’’ in nascent geographic atrophy and for proposing its histologic correlate. Querques et al. first reported this tomographic signature in geographic atrophy with the name of ‘‘wedge-shaped subretinal hyporeflectivity.’’ However, the authors renamed this finding for the following reasons. First, they raise concerns for having two ‘‘hyporeflective wedge’’ descriptors in the same setting of geographic atrophy. However, this concern has already been addressed in previous correspondence, as these two entities involve different structures and are unlikely to be confused. Second, they state that ‘‘wedge-shaped hyporeflectivity’’ is not an accurate descriptor because it does not reflect the appearance of most of these signatures. However, many figures of their article illustrate signatures that remind us of wedgeshaped or triangular compositions, as pointed out in extracts of their original images that here we report in the Figure. Besides these considerations, we have further concerns about the novel descriptor called ‘‘plateau.’’ This signature is not a new finding, but it has already received full interest in the past and renaming may generate confusion. Furthermore, the original descriptor ‘‘wedge-shaped subretinal hyporeflectivity’’ gives insight on the morphology and the position of these abnormalities, while the novel term ‘‘plateau’’ indicates just their morphology, which seems to be still controversial. Taking together all these observations, we feel that no substantial reasons exist to change the original name of this OCT signature and we currently suggest to keep the first descriptor ‘‘wedge-shaped subretinal hyporeflectivity,’’ as originally reported.

Choroidal excavation in choroidal osteoma complicated by choroidal neovascularization

PurposeTo describe multimodal imaging features of choroidal osteoma (CO) complicated by choroidal neovascularization (CNV) and focal choroidal excavation (FCE).MethodsPatients presenting with CO and CNV between January and October 2016 were considered for this study. Diagnosis of CO was confirmed by ultrasound examination. All patients underwent multimodal imaging including optical coherence tomography (OCT), swept-source OCT angiography (DRI OCT Triton, Topcon, Inc., Tokyo, Japan) and fluorescein angiography (Spectralis HRA+OCT; Heidelberg Engineering, Heidelberg, Germany).ResultsTwo patients (one with bilateral CO) were included in the study. OCT showed a FCE in two eyes of two patients (one in correspondence of the CNV and the other adjacent to the CNV). OCT-A demonstrated presence of microvascular flow within neovascular network of the CNVs. Decalcification of the tumor was noted in correspondence of one eye with FCE.ConclusionsFCE may be found in eyes with choroidal osteoma and CNV. OCT-A was a valuable tool for detection of CNV complicating choroidal osteoma. Decalcification of choroidal osteoma may represent a common pathogenic pathway for development of FCE and CNV in choroidal osteoma.

Optical coherence tomography angiography of polypoidal neovascularization associated with choroidal nevus

Purpose To report a case of juxtapapillary polypoidal choroidal neovascularization (PCNV) associated with choroidal nevus investigated by means of optical coherence tomography angiography (OCT-A). Methods Case report. Results A 72-year-old woman presented with visual loss and metamorphopsia in her left eye for 5 days secondary to PCNV that developed on the border of a juxtapapillary choroidal nevus. Fluorescein angiography, indocyanine green angiography, and spectral-domain OCT confirmed the diagnosis. En face OCT-A disclosed a large tangled hyperreflective PCNV spreading from the optic disc at different levels of the choriocapillaris; the polyp lumina appeared hyporeflective. The patient was treated with 3 intravitreal injections of anti-vascular endothelial growth factor with partial functional recovery. Conclusions Our case showed the application of OCT-A in the diagnosis of a case of active PCNV complicating a benign intraocular tumor.

Retinal Pigment Epithelium Humps in High Myopia

PURPOSE To report on the presence of retinal pigment epithelium (RPE) humps in high myopia, and to describe the distinctive features from pathologic RPE detachments and choroidal neovascularizations (CNVs). DESIGN Retrospective cross-sectional study. METHODS Charts and imaging studies of highly myopic patients presenting between September 2015 and February 2017 at a university teaching hospital were consecutively reviewed. All patients underwent spectral-domain optical coherence tomography (OCT). RPE humps were defined as RPE elevations above its physiologic profile, without any evidence of pathologic sub-RPE material. Multimodal imaging was analyzed to assess abnormalities of the RPE and choroid. RESULTS One hundred and ninety-five eyes of 101 highly myopic patients were included. RPE humps on structural OCT were identified in 99 out of 195 eyes (estimated prevalence of 50.8%; 43.8%-57.8, 95% confidence intervals). In all eyes, RPE humps corresponded to large choroidal vessels lifting the RPE. Patchy, diffuse, or CNV-related atrophy was more common in eyes with RPE humps (60.6% vs 34.4%; P < .05). The presence of a large choroidal vessel elevating the RPE and the absence of abnormal material between the RPE and the Bruch membrane were the features distinctive from pathologic RPE detachments and CNVs. DISCUSSION RPE humps were frequently observed in highly myopic eyes and they resulted from the presence of an underlying large choroidal vessel. They are more likely to appear in highly myopic eyes with advanced choroidal atrophy. To prevent unnecessary treatments, they should be distinguished from pathologic RPE detachments and CNVs.

Central Serous Chorioretinopathylike Mimicking Multifocal Vitelliform Macular Dystrophy: An Ocular Side Effect Of Mitogen/extracellular Signal-regulated Kinase Inhibitors.

Purpose: To describe a case of multiple detachments of the neurosensory retina mimicking multifocal vitelliform macular dystrophy after chemotherapy with mitogen/extracellular signal–regulated kinase inhibitor for metastatic ovarian cancer. Methods: Case report. Results: A 38-year-old woman presented to our clinic for eye examination before the initiation of chemotherapy with trametinib. One month after starting treatment, the patient complained of vision loss and metamorphopsia in both eyes. Best-corrected visual acuity decreased from 20/20 at baseline to 20/32 in both eyes, and fundus examination revealed multiple detachments of the neurosensory retina with vitelliformlike appearance, involving the central macula and the posterior pole with a circular distribution along the retinal vascular arcades. Spectral-domain optical coherence tomography showed widespread thickening of the interdigitation zone, particularly in areas with and without detachments, and also some hyporeflective fluid accumulating beneath the detached retina. Mitogen/extracellular signal–regulated kinase inhibitor therapy was discontinued, and after 1 week, best-corrected visual acuity recovered to 20/20 bilaterally, with complete resolution of the serous retinal detachments and normalization of interdigitation zone. Conclusion: The development of a central serous chorioretinopathylike retinopathy is a relatively common secondary event of mitogen/extracellular signal–regulated kinase inhibitors therapy, and typically, it resolves after the discontinuation of the treatment. Our case is peculiar in that the lesions were bilateral, involving the central macula and the posterior pole with a circular distribution along the retinal vascular arcades and in that the interdigitation zone showed a widespread thickening at spectral-domain optical coherence tomography, mimicking multifocal vitelliform macular dystrophy.

Nonproliferative Diabetic Retinopathy

Nonproliferative diabetic retinopathy (NPDR) is classically defined by the presence of early intraretinal microvascular findings and is currently classified into different stages of severity, according to international proposed classifications. Recently, retinal imaging using optical coherence tomography angiography and ultrawide-field angiography has widely improved the morphological analysis of NPDR.