OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY ASSESSMENT OF THE DIABETIC MACULA: A Comparison Study Among Different Algorithms

PURPOSE

To assess the impact of histogram adjustments and binarization thresholding selection on quantitative measurements of diabetic macular ischemia using optical coherence tomography angiography (OCTA).

METHODS

Patients with diabetic retinopathy (DR) who had swept-source OCTA imaging obtained were enrolled. An additional group of 15 healthy control subjects was included for comparison. Previously used brightness/contrast changes and binarization thresholds were applied to original OCTA images to obtain and compare different binarized images. Qualitative and quantitative comparisons were performed.

RESULTS

Thirty patients with DR (30 eyes) were included in the analysis. Fifteen eyes displayed the presence of diabetic macular edema. Qualitative grading revealed that binarized images obtained using a global threshold had better quality compared with local or multistep thresholds. The "median" filter was most frequently graded as the histogram adjustment resulting in binarized images with best quality. In the quantitative analysis, local thresholds tended to generate higher values of measured metrics. Differences in OCTA metrics between global and local thresholds were associated with presence of diabetic macular edema and signal strength index value. In the comparison between healthy and DR eyes, differences in OCTA metrics were significantly affected by binarization threshold selection.

CONCLUSION

Quantitative OCTA parameters may be significantly influenced by strategies to quantify macular perfusion. Image quality and presence of macular edema can significantly impact OCTA-derived quantitative vascular measurements and differences between global and local binarization thresholds. These findings highlight the importance of consistent strategies to reliably generate quantitative OCTA metrics in patients with DR.

USING THREE-DIMENSIONAL OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY METRICS IMPROVES REPEATABILITY ON QUANTIFICATION OF ISCHEMIA IN EYES WITH DIABETIC MACULAR EDEMA

PURPOSE

Two-dimensional (2D) optical coherence tomography angiography (OCTA) is known to be prone to segmentation errors, especially in pathologic eyes. Therefore, our aim was to systematically compare intrasession repeatability between repeated scans for 2D and three-dimensional (3D) OCTA metrics in quantifying retinal perfusion in eyes with diabetic macular edema.

METHODS

Diabetic patients with diabetic retinopathy and diabetic macular edema who had two consecutive OCTA imaging scans obtained during the same visit were retrospectively included. A previously validated algorithm was applied to OCTA volume data to measure the 3D vascular volume and perfusion density. Optical coherence tomography angiography en face images were also processed to obtain 2D perfusion density metrics.

RESULTS

Twenty patients (20 eyes) with diabetic retinopathy and diabetic macular edema were included. The intraclass correlation coefficient ranged from 0.591 to 0.824 for 2D OCTA metrics and from 0.935 to 0.967 for 3D OCTA metrics. Therefore, compared with the 2D OCTA analysis, the intraclass correlation coefficients of the 3D OCTA analysis were higher (without overlapping of the 95% confidential intervals). Similarly, the coefficient of variation (ranging from 2.2 to 4.2 for 2D OCTA metrics and from 1.9 to 2.0 for 3D OCTA metrics) indicated that the 3D OCTA-based quantifications had the highest interscan intrasession agreements. Differences in interscan 2D OCTA metrics' values were associated with average macular volume.

CONCLUSION

Three-dimensional OCTA metrics have higher values of intrasession repeatability, as compared with 2D OCTA metrics. The latter finding seems to be related to the high rate of segmentation errors occurring in diabetic macular edema eyes.

Outer retina dysfunction and choriocapillaris impairment in type 1 diabetes

To study the outer retina morpho-functional characteristics and the choriocapillaris (CC) features in type 1 diabetic (T1D) patients, with and without signs of diabetic retinopathy (NPDR and NoDR). Twenty-five NPDR and 18 NoDR eyes were imaged by Optical Coherence Tomography Angiography. Ellipsoid zone (EZ) “normalized” reflectivity and CC perfusion density parameters, as flow deficits number (FDn), flow deficit average area (FDa) and flow deficit percentage (FD%), were analysed. Multifocal electroretinogram (mfERG) response amplitude densities (RADs) were measured. Mean EZ “normalized” reflectivity, CC FDn and FD% values, were similar (p > 0.05) in both groups, FDa was significant greater (p > 0.05) in NPDR compared with NoDR eyes. MfERG-RADs were similar in both groups. NPDR eyes showed a significant (p < 0.05) linear correlation between RADs and both, CC FDa and FD%. The EZ “normalized” reflectivity was negatively correlated with CC FD% in NoDR eyes. In NPDR T1D eyes a significant relationship between abnormal outer retina functional responses and CC impairment was observed, while in NoDR eyes the photoreceptor reflectivity was correlated to CC abnormalities. The outer retina dysfunction in NPDR correlated to CC drop-out let hypothesize that the outer retinal elements are functionally impaired in proportion to the CC vascular supply deficit.

Imaging Biomarkers of 1-Year Activity in Type 1 Macular Neovascularization

Purpose

The purpose of this study was to evaluate the predictive value of optical coherence tomography (OCT) and OCT angiography (OCTA) parameters at baseline on lesion's activity at the 1-year follow-up in type 1 macular neovascularizations (MNVs) treated with 1-year fixed regimen of intravitreal aflibercept injections (q8 IAIs).

Methods

All patients were imaged by structural OCT to evaluate central macular thickness (CMT), subretinal fluid (SRF), subretinal hyper-reflective material (SHRM), intraretinal fluid (IRF) and intraretinal hyper-reflective dots (HRDs), and by Swept-Source OCTA to measure baseline MNV area, perfusion density (PD), vessel length density (VLD), and vessel diameter index. At the end of q8 IAI, patients were classified in two groups: active-MNV (A-MNV) and inactive-MNV (I-MNV), considering the OCT signs of activity. Three binary logistic regression models were developed: (1) OCT-based, (2) OCTA-based, and (3) OCT/OCTA-based model.

Results

Thirty-one treatment-naïve type 1 MNVs were enrolled (13 A-MNV and 18 I-MNV). No differences were observed in baseline OCT and OCTA characteristics between A-MNV and I-MNV. Among the models developed, model 3 that combined OCT/OCTA parameters showed a performance of 87.5% and excellent sensitivity for A-MNV lesions (100%). By analyzing the model, the A-MNV group appears more likely to show at baseline SRF, greater CMT, wider MNV area, and lower PD and VLD compared to I-MNV.

Conclusions

Our study demonstrated that the combination of baseline OCT and OCTA parameters allowed to achieve a good models’ performance in the prediction of MNV activity permitting to correctly classifying the active lesions at the end of follow-up period, with excellent sensitivity.

Translational Relevance

OCT/OCTA could integrate statistical models potentially useful for artificial intelligence.

Characterisation of macular neovascularisation in geographic atrophy

AIM

To characterise macular neovascularisation (MNV) developing in eyes affected by geographic atrophy (GA).

METHODS

In this multicentric longitudinal study involving three retina referral centres, patients previously affected by GA who developed an active MNV were included. Patients were investigated using structural optical coherence tomography (OCT), fundus autofluorescence, OCT-angiography and dye angiographies. Patients were treated with ProReNata antivascular endothelial growth factor (VEGF) injections and were revaluated after treatment.

RESULTS

Among 512 patients previously diagnosed with GA, 40 eyes of 40 patients (mean age 80.8±7.9 years, mean GA area 8.73±7.39 mm²) presented with treatment-naïve exudative MNV (accounting for an estimated prevalence of 7.81%; 5.49 to 10.13, 95% CIs) and thus were included in the analysis. 67.5% of MNVs were classified as type 2 MNV, 25% as type 1, 2.5% as type 3 and 5% as mixed phenotype. In 92.5% of cases, active MNV in GA showed subretinal hyperreflective material with or without evidence of subretinal/intraretinal hyporeflective exudation. During a mean follow-up of 28±25 months, patients were treated with 6.6±6.3 anti-VEGF injections, with 2.9±1.4 injections in the first year of treatment. No patient developed GA enlargement in the area of MNV.

CONCLUSIONS

MNVs in GA showed different features and therapeutic response in comparison to previously reported features of MNV in age-related macular degeneration (AMD) without GA. For these reasons, the combined phenotype (ie, GA with neovascular AMD) should be considered as a distinct entity in the research and clinical setting.

Treatment-naïve quiescent macular neovascularization secondary to AMD: The 2019 Young Investigator Lecture of Macula Society

PURPOSE

To analyze different clinical and anatomical features in treatment-naïve non-exudative macular neovascularizations (MNVs) secondary to age-related macular disease (AMD).

METHODS

In this retrospective longitudinal study with a minimum follow-up of 1 year, 31 eyes of 28 consecutive AMD patients (mean age 75 ± 9 years) with treatment-naïve non-exudative MNV were enrolled. Patients were divided in: short-term activated MNV group (exudation before 6-month) and quiescent MNV group (per definition no exudation during a minimum 6-month follow-up) showing no or late activation during follow-up (persistently quiescent and long-term activated MNV group, respectively).

RESULTS

During the follow-up (mean duration: 22 ± 9 months) four eyes (13%) showed exudation before 6-month follow-up (short-term activated MNV group), whereas 21 eyes (68%) did not develop signs of exudation (persistently quiescent group), and six eyes (19%) developed exudation after the minimum 6-month follow-up (long-term activated MNV group). Monthly MNV growth rate was significantly higher in the short-term activated MNV group (growth rate of 13.30%/month), vs persistently quiescent MNV group (0.64%/month, p < 0.001) and long-term activated quiescent MNV group (1.07%/month, p < 0.001). Furthermore, at the baseline, perfusion density of short-term activated MNV group was significantly greater in comparison to persistently quiescent MNV group (p = 0.001) and long-term activated MNV group (p = 0.106).

CONCLUSION

We reported two different patterns for subclinical MNVs: subclinical MNVs characterized by short-term activation which could represent simply a pre-exudative stage in the development of an ordinary type 1 MNV, and quiescent MNVs characterized by low rate of growth and possible long-term activation. Analysis of OCT-A features may predict short-term activation for subclinical MNV but no features could predict the long-term activation.

Guidelines on Optical Coherence Tomography Angiography Imaging: 2020 Focused Update

Optical coherence tomography angiography (OCTA) has significantly expanded our knowledge of the ocular vasculature. In this review, we provide a discussion of the fundamental principles of OCTA and the application of this imaging modality to study the retinal and choroidal vessels. These guidelines are focused on 2020, and include updates since the 2019 publication. Importantly, we will comment on recent findings on OCTA technology with a special focus on the three-dimensional (3D) OCTA visualization.

Macular Functional and Morphological Changes in Intermediate Age-Related Maculopathy

Purpose

The purpose of this study was to evaluate macular preganglionic function and to verify its relationship with retinal and choroidal morphology in patients with intermediate age-related macular degeneration (iAMD) patients.

Methods

All included patients performed multifocal electroretinogram (mfERG) for investigating on macular function from the central 15° of foveal eccentricity, spectral domain optical coherence tomography (SD-OCT) for studying retinal structure, enhanced depth imaging OCT (EDI-OCT) for the measure of choroidal vascularity index (CVI), and OCT-angiography (OCTA) for the evaluation of vessel density (VD) in the superficial and deep capillary plexus, and choriocapillaris (CC) layer.

Results

Twenty-seven patients with iAMD and 20 age-matched control eyes were analyzed. Significantly (P < 0.01) delayed and reduced mfERG responses in the central 0 to 2.5°, paracentral 2.5 to 5°, and overall 0 to 5° areas, as well as increased CVI values in both foveal (1 mm centered to the fovea) and fovea + parafovea areas (3 mm centered to the fovea), increased foveal and parafoveal (annular area of 1-3 mm centered to the fovea) retinal pigment epithelium thickness, and volume and parafoveal outer retinal volume were found in iAMD eyes as compared to controls. Moreover, iAMD eyes showed significantly (P < 0.01) reduced foveal and parafoveal OCTA-VD values in the CC layer when compared to controls. In the iAMD group, not significant (P > 0.01) correlations were found between morphological and functional parameters.

Conclusions

Our findings support a dysfunction of photoreceptors and bipolar cells in both foveal and parafoveal areas in the presence of outer retina, CC, and choroidal structural changes, however, not significantly correlated. The observed enlargement of luminal choroidal area (measured by CVI) is possibly compensatory to CC vascular insufficiency.

Profile of non-responder and late responder patients treated for diabetic macular edema: systemic and ocular factors

Diabetic macular edema (DME) treatment represents a challenge for the ophthalmologists, and several aspects of real treatment expectancy are still being discussed and not yet fully elucidated. A univocal definition of responsiveness to treatment has not been reached. How the clinicians can evaluate the therapeutic success? The evaluation of systemic and ocular factors should help in this complex management. The age influences the long-term outcomes, and the role of glycemic control is confounded by contrasting correlations between hemoglobin glycated A1c and DME. Long-term treatment success is influenced by baseline best-corrected visual acuity (BCVA), central macular thickness (CMT) and early BCVA response. Also baseline diabetic retinopathy severity scale score is useful to evaluate the chances of improvement before and during treatments. The time-switching was influenced by early BCVA response, however considering a delayed response in a percentage of patients. Several structural optical coherence tomography (OCT) findings could predict long-term success, as the presence of serous retinal detachment, hyperreflective retinal spots, the disruption of external limiting membrane and ellipsoid zone, the disorganization of inner retinal layers and continued increase in CMT were considered predictors of poor response to treatment. Foveal avascular zone enlargement, high number of microaneurysms (Mas), lower vessel density (VD) in deep capillary plexus and lower parafoveal VD in superficial capillary plexus were considered as OCT angiography biomarkers of poor responsiveness. The aim of this review is to report the factors that could influence the response to treatment of DME patients.

Diurnal trajectories of salivary cortisol and α-amylase and psychological profiles in patients with central serous chorioretinopathy

It has been hypothesized that the occurrence of central serous chorioretinopathy (CSC) might be associated with stress. Therefore, our purpose was to investigate the diurnal trajectories of salivary cortisol and α-amylase (α-Amy) - markers of hypothalamic-pituitary-adrenal (HPA) axis and sympathetic-adrenal-medullary (SAM) system activity, respectively - and psychological profiles in idiopathic acute CSC. This cross-sectional observational case-control study, which included self-reported psychometric questionnaires, was formally approved by the Ethics Committee. Written informed consent was obtained from all participants. Home diurnal saliva collection was scheduled at several timepoints: at awakening, 30 and 60 min later, and at approximately 13:00 h and 20:00 h. Twenty consecutive male subjects with first-episode CSC attending the outpatient clinic of the Retina Medical Service at the Bietti Foundation were enrolled in the study. Twenty age-matched subjects were recruited as controls. After their initial enrollment, 3 subjects per group were excluded. The production of cortisol and α-Amy and the scores on the negative subscale of the Positive/Negative Affect Schedule, the Daily Hassles and Stress Scale and the Beck Depression Inventory were higher in the CSC group than in the control group. To estimate the diurnal trends in the production of salivary cortisol and α-Amy, an equation was derived for each group of the study population. The equations describing the interpolated regression lines gave salivary cortisol and salivary α-Amy slopes that were determined to be significantly different by Student's t-test (cortisol: t = 3.533, p < .001; α-Amy: t = 2.382, p = .018). Furthermore, the area under the curve with respect to the ground (AUC_G) was calculated to summarize repeated salivary biomarker measurements from 07:00 h to 08:00 h for assessment of the cortisol awakening response (CAR) and the α-Amy awakening response (AR). The diurnal cortisol AUC_G and diurnal α-Amy AUC_G were calculated from 07:00 h to 20:00 h. The CAR AUC_G values of the CSC patients were significantly higher than those of the controls. No differences between the two groups were detected for the α-Amy AR AUC_G. The present study adds novel information to the growing body of data suggesting that abnormal diurnal activity of the HPA axis and the SAM system is associated with CSC in susceptible individuals, providing ophthalmologists with a new chronobiological approach for these patients.

Appearance of cysts and capillary non perfusion areas in diabetic macular edema using two different OCTA devices

The aim of this paper was to distinguish the appearance of cysts and non-perfusion areas (NPAs) in diabetic macular edema (DME) using two different Optical Coherence Tomography Angiography (OCTA) devices. In this study, patients underwent OCTA using the AngioVue XR Avanti Spectral Domain (SD) OCTA and the PLEX Elite 9000 Swept-Source (SS) OCTA. Foveal and extrafoveal regions of interest (ROI), defined as any area with an altered flow signal comparing to the surrounding retina, were selected in superficial and deep capillary plexus (SCP and DCP). ROI reflectivity were classified as hypo-reflective or hyper-reflective. Foveal ROI were analyzed to detect suspended scattering particles in motion (SSPiM). Thirty-seven DME eyes were included. A larger number of ROIs were found in SCP (55 vs 39) and DCP (60 vs 49) using PLEX Elite 9000 vs AngioVue. The majority of ROIs were hypo-reflective with both instruments, while slightly more hyper-reflective ROIs (grey) were detected with the PLEX Elite, more likely to be cysts. The hyporeflective ROIs could be NPAs or cysts with both devices. Moreover, PLEX Elite 9000 identified SSPiM in more foveal ROIs than the AngioVue in the SCP (p = 0.005) and in the DCP (p = 0.027). In conclusion, NPAs and cysts may show variable appearances using different OCTA devices. Hyperreflective ROIs generally correspond to cysts, hyporeflective ROIs can be either cysts or NPAs. The SS-OCTA seems to detect SSPiM more frequently than the SD-OCTA.

Pharmacotherapy of Central Serous Chorioretinopathy: A Review of the Current Treatments

BACKGROUND

Central serous chorioretinopathy (CSC) is the fourth most frequent retinal disorder in terms of prevalence. It typically occurs in young subjects and affects men more often than women. CSC is characterized by serous retinal detachment (SRD) involving mainly the macular area. The clinical course is usually selflimited, with spontaneous resolution within 3 months. The persistence of SRD or multiple relapse may result in a chronic form of CSC distinguished by permanent retinal pigment epithelium (RPE) and photoreceptor damage. As the pathogenetic mechanism of CSC primarily involves RPE and choroidal vascularization, the current therapeutic approaches aim to restore the normal functions of RPE and normal choroidal vascular permeability. In this review, the authors aim to summarize the current therapeutic approach to CSC.

METHODS

A comprehensive review of the literature was conducted in PubMed by searching for relevant studies on the current therapeutic options for CSC, including simple observation, conventional laser treatment, subthreshold laser treatment (SLT), photodynamic therapy (PDT) with verteporfin, treatment with mineralocorticoid receptor (MR) antagonists and treatment with anti-vascular endothelial growth factor drugs.

RESULTS

Since most cases resolve spontaneously, the most common initial CSC treatment is observation. Current evidence suggests that PDT and SLT are valuable in improving visual acuity, reducing subretinal fluid and maintaining long-term effectiveness. No clear evidence of efficacy has been achieved for anti-VEGF. MR antagonists might be a viable choice for the treatment of chronic CSC.

CONCLUSION

The pathophysiology of CSC remains poorly understood and as a consequence, the gold standard of care for CSC is yet to be defined. To date, PDT and SLT continue to offer good clinical outcomes. Positive preliminary results seem to emerge from the studies of MR antagonists.

Impact of Bleaching on Photoreceptors in Different Intermediate AMD Phenotypes

Purpose

To investigate photoreceptors' structural changes after photobleaching exposure in intermediate age-related macular degeneration (iAMD) eyes with and without reticular pseudodrusen (RPD).

Methods

In this prospective, cross-sectional study, were enrolled iAMD patients and healthy controls. Patients and controls underwent repeated imaging with spectral-domain optical coherence tomography (SD-OCT), at baseline and at three intervals after bleaching, during the subsequent recovery in darkness. Structural changes in photoreceptors were investigated in the foveal region and in four perifoveal areas.

Results

Twenty eyes of 20 iAMD patients (12 with RPD and 8 without RPD) and 15 age-matched healthy controls were enrolled. At baseline, the photoreceptor outer segment (OS) volume was significantly reduced in iAMD eyes with RPD compared with controls, in the foveal and perifoveal regions. In healthy subjects, a precocious increase in OS volume was observed after bleaching in the foveal region, and a rapid recovery to baseline values was recorded. In the perifoveal regions, an increase in OS volume was observed 10 minutes after light onset. In contrast, in iAMD subjects with RPD an altered response to photobleaching, in the foveal and superior and inferior perifoveal regions, was recorded.

Conclusions

Our imaging evidences support the hypothesis that dark adaptation is more altered in eyes with RPD. The structural modifications may explain the functional increased damage of the retinal pigment epithelium and photoreceptors reported in eyes with RPD.

Translational Relevance

OCT imaging may be used to assess dark adaptation in AMD eyes.

Correction to: Effects of Macuprev® Supplementation in Age-Related Macular Degeneration: A Double-Blind Randomized Morpho-Functional Study Along 6 Months of Follow-Up

The article ''Effects of Macuprev Supplementation in Age-Related Macular Degeneration: A Double-Blind Randomized Morpho-Functional Study Along 6 Months of FollowUp'', written by Mariacristina Parravano, Massimiliano Tedeschi, Daniela Manca, Eliana Costanzo, Antonio Di Renzo, Paola Giorno, Lucilla Barbano, Lucia Ziccardi, Monica Varano, Vincenzo Parisi was originally published electronically on the publisher's internet portal (currently SpringerLink) on June 25, 2019 without Open Access. The article has now been made Open Access.

Optical Coherence Tomography Parameters as Predictors of Treatment Response to Eplerenone in Central Serous Chorioretinopathy

Purpose: To present data on clinical response to eplerenone over a 1-year period in patients with central serous chorioretinopathy (CSC), and to evaluate optical coherence tomography (OCT) variables as predictors of treatment response at 3- and 12-month follow-up visits. Methods: Patients with acute or chronic CSC treated with eplerenone were retrospectively included. Clinical and imaging characteristics were recorded at baseline and at the 3-month and 12-month follow-up visits. Changes from baseline in quantitative measurements were calculated at each follow-up. Logistic regression analysis was computed to correlate clinical and OCT parameters at baseline with response to treatment at 3 and 12 months of follow-up. Results: A total of 50 eyes of 50 patients were included in the study. Mean ± SD best corrected visual acuity (BCVA) was 0.20 ± 0.14 Logarithm of the Minimum Angle of Resolution (LogMAR) at baseline and significantly improved at both the 3-month (0.12 ± 0.13 LogMAR, p < 0.0001) and 12-month (0.10 ± 0.12 LogMAR, p < 0.0001) follow-up visits. At the 3-month follow-up visit, 25 out of 50 eyes (50.0%) demonstrated macular complete subretinal fluid (SRF) resolution, while 13 eyes (26.0%) showed macular partial SRF resolution, and 12 eyes (24%) had neither partial nor complete macular SRF resolution. Among those patients with macular partial or complete SRF resolution at 3 months and thus not shifted to photodynamic therapy, 36 out of 38 cases had macular complete SRF resolution at the 12-month follow-up visit. There was a significant change from baseline at both follow-up visits in all anatomical OCT parameters (except for reduction in choroidal thickness that did not reach the statistical significance at the 12-month follow-up visit). Several OCT parameters at baseline were independently significant predictors for macular subretinal fluid complete resolution at 3 months, including (i) a thicker subfoveal choroidal thickness; (ii) a smaller subretinal fluid maximum diameter; (iii) a lower number of serous pigment epithelium detachments; and (iv) a lower number of intraretinal hyperreflective foci. Conclusion: Treatment with eplerenone in CSC patients is confirmed to be beneficial for both anatomical and functional outcomes. We identified attractive OCT metrics that could potentially be used as a tool to select patients who might mainly benefit from this treatment.

A Comparison Among Different Automatically Segmented Slabs to Assess Neovascular AMD using Swept Source OCT Angiography

Purpose

We systematically compare the intermodality and interreader agreement in age-related macular degeneration(AMD)-associated neovascularization assessment for optical coherence tomography angiography (OCTA) images obtained using different slabs.

Methods

We collected data from 48 patients (50 eyes) with type 1 or 2 neovascularization (NV) and AMD. Subjects were imaged with a swept source (SS)-OCTA system. For each eye, three OCTA en face images generated from three different slabs were exported: (1) the outer retina to choriocapillaris (ORCC) image, (2) the choriocapillaris (CC) image, and (3) the retinal pigment epithelium (RPE)-RPE fit image. Each image was graded by two readers to assess interreader variability and a single image for each modality was used to assess the intermodality variability.

Results

In the assessment of type 1 NV, mean absolute interreader difference between measured NV areas was 0.19, 0.30, and 0.16 mm² for ORCC, CC, and RPE-RPE fit images, respectively. Similarly, the coefficient of repeatability (CR) and intraclass correlation coefficient (ICC) indicated that the RPE-RPE fit assessment was characterized by the highest interreader reproducibility. Type 1 NV size was 0.58 mm² (0.30–1.60 mm²) on ORCC images, 0.00 mm² (0.00–0.36 mm²) on CC images (P = 0.002 vs. ORCC), and 0.62 mm² (0.31–2.03 mm²) on RPE-RPE fit images (P < 0.0001 vs. CC, P = 0.041 vs. ORCC).

Conclusions

The RPE-RPE fit OCTA images have the highest interreader agreement and deliver larger measurements in type 1 lesions.

Translational Relevance

OCTA imaging may be used in ongoing trials of potential novel treatments for NV.

Microvascular Retinal and Choroidal Changes in Retinal Vein Occlusion Analyzed by Two Different Optical Coherence Tomography Angiography Devices

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-is-chemic 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.

Choroidal Caverns: A Novel Optical Coherence Tomography Finding in Geographic Atrophy

Purpose

To describe and interpret “choroidal caverns,” an unreported optical coherence tomography (OCT) finding in the choroid of patients with geographic atrophy (GA) secondary to atrophic AMD.

Methods

Retrospective analysis of patients with GA. Main outcomes measures included estimation of the prevalence of choroidal caverns, their localization and relation with retinal-choroidal structures by reviewing medical records and multimodal imaging.

Results

One hundred twenty consecutive patients (mean age 80.5 ± 8.61 years) were included. Among the 201 eyes with GA, 17 eyes of 15 patients presented choroidal caverns on OCT B-scan in GA areas (a total of 43 choroidal caverns, mean 2.5/eye, variably localized in the Sattler and Haller layers, with relative preservation of the choriocapillaris). This accounts for 12.5% estimated prevalence (6.5–18.5, 95% confidence interval [CI]) of choroidal caverns in GA areas of atrophic AMD patients. Choroidal caverns appeared on OCT (both B-scan and en face) as gaping hyporeflective cavities in the choroid, typically empty, angular, without hyperreflective borders, often with punctate/linear hyperreflectivities internally. Indocyanine angiography and OCT-Angiography confirmed that the areas occupied by these cavities do not represent perfused choroidal blood vessels.

Conclusions

Choroidal caverns represent a relatively infrequent peculiar finding in GA areas of atrophic AMD eyes. They appear as gaping angular hyporeflective cavities in areas devoid of choroidal vessels, often with punctate/linear hyperreflectivities internally. Choroidal caverns may possibly arise from nonperfused ghost vessels and persistence of stromal pillars where the vessels were originally situated.

Brain connectivity in patients with schizophrenia related to psychological stress

Introduction

It is commonly accepted that in most patients with schizophrenia external factors act on genetic predisposition to produce active psychotic symptoms. In fact, we showed that patients with schizophrenia have an abnormal brain activation and peripheral autonomic response to psychological stress. We sought to characterize the brain connectivity networks of such response in schizophrenia.

Methods

We studied the pattern of brain connectivity in relation to mental arithmetic stress paradigm in 21 patients and 21 healthy subjects aged 18 to 50 years, using 3T-fMRI. A period of 6 minutes of resting state acquisition (PRE) were followed by a block design with three 1-minute CONTROL task (one digit sum), 1-minute STRESS task (two digit subtraction) and 1-minute rest after task (POST). Pairwise Pearson correlations were calculated between 90 regions of interest. Data were analyzed with MATLAB and SPSS software.

Results

Patients with schizophrenia showed a lower connectivity network between fronto-temporal limbic areas compared with control subjects during control and stress task. Moreover, we observed a great variability of link density during resting state in patients but not in controls, and it diminishes in response to task.

Conclusions

Patients present abnormalities in networks related to stress response showing an alteration in fronto-temporal connectivity, and a poor and random modulation of these networks at rest. Current and previous findings suggest abnormal fronto-temporal connectivity that ultimately would lead to psychotic symptoms emergency in response to an environmental stressor and, even, could be related to hypervigilance and misattribution feeding into the paranoid cognition characteristic of patients with schizophrenia.

Disclosure of interest

The authors have not supplied their declaration of competing interest.

RETINAL PIGMENT EPITHELIUM APERTURE: A Previously Unreported Finding in the Evolution of Avascular Pigment Epithelium Detachment

PURPOSE

To describe retinal pigment epithelium (RPE) aperture and to generate hypotheses about pathogenesis of this previously unreported finding in the evolution of avascular pigment epithelium detachment (PED) secondary to age-related macular degeneration.

METHODS

Medical records and multimodal imaging results from 10 patients with RPE apertures were reviewed between January 2009 and December 2014 by 2 institutions. Main outcome measures were analysis of RPE aperture imaging characteristics, including aperture areas and PED diameters, and their temporal course. Lesions preceding RPE aperture development were also evaluated.

RESULTS

Eleven RPE apertures were identified in 10 eyes of 10 patients (1 male, 9 females; mean age 73.1 ± 6.7 years) and included for analysis. The RPE apertures appeared as round discontinuities either at the apex or at the base of avascular PED. No rippling or retraction of the RPE was found at the sites of aperture. The RPE apertures enlarged homogeneously (mean round area of hypoautofluorescence significantly increased from 0.18 ± 0.13 to 0.93 ± 1.2; P = 0.005), and PED flattened (PED maximal height on spectral domain optical coherence significantly decreased from 445.2 ± 259 to 206.4 ± 218; P = 0.04) after a mean of 38.6 ± 16.3 months. Analysis of lesions preceding RPE apertures revealed areas of focal hyperautofluorescence at the site of development, in some cases appearing as drusenoid material connected with the base of avascular PED.

CONCLUSION

The RPE aperture represents a previously unreported possible evolution of avascular PED, which should be distinguished by typical RPE tears. Analysis of lesions preceding RPE apertures suggests focal atrophic progression of drusenoid material in its pathogenesis.

Hyperreflective Choroidal Vessels in Geographic Atrophy Secondary to Age-Related Macular Degeneration

BACKGROUND AND OBJECTIVE

To describe choroidal vessels in areas of geographic atrophy (GA) secondary to age-related macular degeneration that appear as hyperreflective choroidal vessels (HRCVs) on multicolor (MC) imaging.

PATIENTS AND METHODS

Retrospective case series of patients with GA. Multimodal imaging evaluation was performed.

RESULTS

HRCVs, which seem to be sclerotic on MC imaging, appeared as hyperautofluorescent on fundus autofluorescence, clearly distinguishable over the background of hypo-autofluorescence, and correlated with late-phase hypocyanescence areas on indocyanine green angiography. Average size of GA areas was significantly larger in eyes with (4.19 mm ± 0.83 mm) compared to eyes without (3.22 mm ± 1.05 mm) HRVCs (P = .0002). Similarly, mean choroidal thickness (CT) was significantly thinner in eyes with (78.5 µm ± 33.8 µm) compared to eyes without (155.4 µm ± 69.8 µm) HRVCs (P < .0001).

CONCLUSIONS

HRCVs are more clearly distinguishable than other choroidal vessels on MC imaging in GA. HRCV identification is more frequent in eyes with larger areas of atrophy and reduced CT, and thus possibly represent a maker of more advanced GA. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:1106-1114.].