Double-layer Sign Research Articles

Longitudinal structural changes in central serous chorioretinopathy: A multimodal imaging-based study.

To analyse the longitudinal changes in imaging parameters in eyes with acute or chronic central serous chorioretinopathy (CSCR). This was a multicentric, retrospective, longitudinal, observational study in patients with a diagnosis of CSCR and having at least 4 years of follow-up. Trend in choroidal thickness (CT), area of double layer sign (DLS), area of retinal pigment epithelium (RPE) alterations, and area of hyper-autofluorescence were analysed. A total of 175 eyes of 146 patients with a mean age of 52.9 ± 12.5 years were included. Fifty-two eyes had acute and 123 had chronic CSCR at baseline. There was an overall decreasing trend of CT values during follow up (from 354.4 ± 74.8 at baseline to 343.2 ± 109.4 at final visit). There was a steady rise in DLS width and RPE alteration in the overall cohort (from 811.7 ± 760.6 microns and 3.5 ± 3.3 disc areas respectively at baseline to 1209.1 ± 1113.18 microns, 4.1 ± 3.6 disc areas at final visit). An initial rise in hyper-autofluorescent area followed by steady fall was seen in chronic CSCR. A significant positive correlation (r = 0.54, p = 0.004) was seen between change in DLS width and change in area of hyper-autofluorescence. On linear regression analysis, lower CMT and absence of intraretinal fluid at baseline were associated with greater increase in RPE abnormalities. Acute and chronic CSCR had different pattern of change in imaging parameters with area of RPE alterations in acute CSCR not reaching values close to that of chronic CSCR eyes even after long follow up.

Choroidal imaging biomarkers as predictors of conversion to exudative age-related macular degeneration.

Predicting the progression of intermediate AMD (iAMD) to neovascular AMD (nAMD) will help to identify high-risk patients and improve treatment outcomes. The present study assessed whether choroidal OCT biomarkers could predict conversion to nAMD. This retrospective study included patients with clinically stable iAMD who either converted to nAMD (C group) or did not convert (NC group) during one year of follow-up. OCT parameters included subfoveal choroidal thickness (SFCT), central macular thickness (CMT), Haller vascular thickness (HVT), inner choroidal thickness (ICT), and double-layer sign (DLS). Of 116 total eyes, there were 37 in the NC group and 79 in the C group. Baseline SFCT was significantly lower in the C group compared to the NC group (169.0 ± 63.2μm vs. 218.0 ± 97.8μm, p = 0.01). Baseline HVT and ICT were lower in the C group (105.2 ± 40.6μm vs. 121.0 ± 56.6μm, p = 0.17 and 61.9 ± 35.5μm vs. 77.5 ± 41.7μm, p = 0.09). HVT was decreased at all time points in the C group vs NC (p > 0.05). The ICT was reduced in the C group at each time point except at conversion time (p > 0.05). Of all eight eyes who presented DLS at baseline, 100% converted to nAMD (p < 0.001). Lower SFCT at baseline may signal conversion to nAMD within 12months.

Predict and Protect: Evaluating the Double-Layer Sign in Age-Related Macular Degeneration.

Advanced age-related macular degeneration (AMD) is a major cause of vision loss. Therefore, there is interest in precursor lesions that may predict or prevent the onset of advanced AMD. One such lesion is a shallow separation of the retinal pigment epithelium (RPE) and Bruch's membrane (BM), which is described by various terms, including double-layer sign (DLS). In this article, we aim to examine and clarify the different terms referring to shallow separation of the RPE and BM. We also review current evidence on the outcomes associated with DLS: firstly, whether DLS is predictive of exudative neovascular AMD; and secondly, whether DLS has potential protective properties against geographic atrophy. The range of terms used to describe a shallow separation of the RPE and BM reflects that DLS can present with different characteristics. While vascularised DLS appears to protect against atrophy but can progress to exudation, non-vascularised DLS is associated with an increased risk of atrophy. Optical coherence tomography (OCT) angiography (OCTA) is the principal method for identifying and differentiating various forms of DLS. If OCTA is unavailable or not practically possible, simplified classification of DLS as thick or thin, using OCT, enables the likelihood of vascularisation to be approximated. Research is ongoing to automate DLS detection by applying deep-learning algorithms to OCT scans. The term DLS remains applicable for describing shallow separation of the RPE and BM. Detection and classification of this feature provides valuable information regarding the risk of progression to advanced AMD. However, the appearance of DLS and its value in predicting AMD progression can vary between patients. With further research, individualised risks can be confirmed to inform appropriate treatment.

Comparison between indocyanine green angiography and optical coherence tomography angiography for the detection of nonexudative macular neovascularization.

Patients with unilateral treatment-naïve exudative neovascular age-related macular degeneration (nAMD) were examined for the presence of nonexudative macular neovascularization (neMNV) in their fellow eye using a multimodal imaging approach. This is intended to determine the sensitivity of individual imaging methods, namely, indocyanine green angiography (ICGA) and optical coherence tomography angiography (OCTA). In this retrospective cross-sectional study, ICGA images of the nonexudative eye were analyzed for the presence of plaques. SS-OCTA outer retinal segmentations were evaluated for neovascular flow in en-face scans and/or color-coded flow in B-scans. The findings were matched with a double-layer sign (DLS) or pigment epithelium detachment (PED) on conventional OCT. In total, neMNV was diagnosed in the fellow eye of 40 of 241 patients (17%) using a multimodal imaging approach employing both ICGA and SS-OCTA. 25 eyes (10%) showed neMNV in both modalities, while 7 (3%) were only detected by ICGA and 8 (3%) by OCTA alone. The sensitivities of ICGA therefore were 80% (32/40) and 83% (33/40) for OCTA. Of the 40 eyes with neMNV, OCT revealed DLS in 25/40 (63%) and PED in 17/40 (43%) of the cases. None of the modalities alone could detect all neMNV in the partner eye of Caucasians with unilateral treatment-naïve exudative nAMD. ICGA and OCTA showed comparable sensitivity. The combination of ICGA, OCTA, and OCT provides the most comprehensive screening for this AMD subtype.

BULBOSITIES AND INTERVORTEX VENOUS ANASTOMOSIS IN VENOUS OVERLOAD CHOROIDOPATHY MASQUERADING AS POLYPOIDAL CHOROIDAL VASCULOPATHY.

To describe a patient with venous overload choroidopathy in whom venous bulbosities masqueraded as polyps and intervortex venous anastomosis mimicked a branching vascular network, giving the appearance of polypoidal choroidal vasculopathy. The patient had complete ophthalmic examination including indocyanine green angiography and optical coherence tomography. Venous bulbosities were defined on indocyanine green angiography as focal dilations in which the diameter of the dilation is two times that of the host vessel. A 75-year-old woman presented with combined subretinal and subretinal pigment epithelium hemorrhages in the right eye. During indocyanine green angiography, focal nodular hyperfluorescent lesions connected to a network of vessels were observed, which looked like polyps and branching vascular network in polypoidal choroidal vasculopathy. In both eyes, the midphase angiogram had multifocal choroidal vascular hyperpermeability. There was late-phase placoid staining nasal to the nerve in the right eye. During enhanced depth imaging-optical coherence tomography evaluation, there were no retinal pigment epithelium elevations that would be expected with polyps or branching vascular network in the right eye. A double-layer sign was seen corresponding to the placoid area of staining. Diagnosis of venous overload choroidopathy and choroidal neovascularization membrane was made. She was treated with intravitreal antivascular endothelial growth factor injections for the choroidal neovascularization membrane. Indocyanine green angiography findings in venous overload choroidopathy may mimic polypoidal choroidal vasculopathy, but differentiation is essential because it has implications for treatment. Similar findings may have been misinterpreted in the past and may have previously contributed to conflicting clinical and histopathologic descriptions of polypoidal choroidal vasculopathy.

COMPARISON OF CHOROIDAL VASCULATURE BETWEEN CENTRAL SEROUS CHORIORETINOPATHY WITH AND WITHOUT THICK CHOROID USING SWEPT-SOURCE OPTICAL COHERENCE TOMOGRAPHY ANGIOGRAPHY.

To distinguish between central serous chorioretinopathy (CSC) with and without thick choroid and to elucidate their characteristics of choroidal vasculature. This prospective observational study enrolled 76 eyes with treatment-naive CSC and 76 normal eyes. Mean + 2 times SD of subfoveal choroidal thickness of healthy individuals was set as the upper limit of normal choroidal thickness to divide patients with CSC into two groups: the thick-choroid and non-thick-choroid groups. Their choroid blood flow was compared using widefield swept-source optical coherence tomography angiography. According to the discrimination value of subfoveal choroidal thickness as 326.8 µm, 76 eyes with CSC were divided into the thick-choroid (55, 72.4%) and non-thick-choroid (21, 27.6%) groups. Higher proportions of vortex vein anastomosis were found in the thick-choroid group (81.8% vs. 33.3%, P < 0.001). Choroid thickness, three-dimensional choroidal vascularity index, and mean choroidal stroma volume per 1 mm2 were higher in the thick-choroid group. In multivariate analysis, younger age, higher percentages of vortex vein anastomosis, and double layer sign were the independent predictors of choroid thickening in CSC. There are discrepancies in the degree of choroidal congestion and distribution of vortex veins in the CSC with different choroidal thicknesses.

Integrating Machine Learning and Traditional Survival Analysis to Identify Key Predictors of Foveal Involvement in Geographic Atrophy.

The purpose of this study was to investigate the incidence of foveal involvement in geographic atrophy (GA) secondary to age-related macular degeneration (AMD), using machine learning to assess the importance of risk factors. Retrospective, longitudinal cohort study. Patients diagnosed with foveal-sparing GA, having GA size ≥ 0.049mm² and follow-up ≥ 6months, were included. Baseline GA area, distance from the fovea, and perilesional patterns were measured using fundus autofluorescence. Optical coherence tomography assessed foveal involvement, structural biomarkers, and outer retinal layers thickness. Onset of foveal involvement was recorded. Foveal survival rates were estimated using Kaplan-Meier curves. Hazard ratios (HRs) were assessed with mixed model Cox regression. Variable Importance (VIMP) was ranked with Random Survival Forests (RSF), with higher scores indicating greater predictive significance. One hundred sixty-seven eyes (115 patients, average age = 75.8 ± 9.47years) with mean follow-up of 50 ± 29months, were included in this study. Median foveal survival time was 45months (95% confidence interval [CI] = 38-55). Incidences of foveal involvement were 26% at 24months and 67% at 60months. Risk factors were GA proximity to the fovea (HR = 0.97 per 10-µm increase, 95% CI = 0.96-0.98), worse baseline visual acuity (HR = 1.37 per 0.1 LogMAR increase, 95% CI = 1.21-1.53), and thinner outer nuclear layer (HR = 0.59 per 10-µm increase, 95% CI = 0.46-0.74). RSF analysis confirmed these as main predictors (VIMP = 16.7, P = 0.002; VIMP = 6.2, P = 0.003; and VIMP = 3.4, P = 0.01). Lesser baseline GA area (HR = 1.09 per 1-mm2 increase, 95% CI = 1.01-1.16) and presence of a double layer sign (HR = 0.42, 95% CI = 0.20-0.88) were protective but less influential. This study identifies anatomic and functional factors impacting the risk of foveal involvement in GA. These findings may help identify at-risk patients, enabling tailored preventive strategies.

Optical Coherence Tomography-Based Positive Predictors of Eplerenone Therapy in Chronic Central Serous Chorioretinopathy: A Retrospective Study.

This study aimed to investigate optical coherence tomography (OCT) biomarkers as potential predictors of treatment response in chronic central serous chorioretinopathy (CSCR). It was a retrospective cohort study that included 42 patients with chronic CSCR. After complete ocular and hematological examinations, all patients received 50 mg/day of oral eplerenone for three months and were followed for at least six months. All participants were divided into two groups: Group 1 participants with a positive response to treatment (complete resolution of subretinal fluid (SRF) at six months) and Group 2 poor responders (moderate or less than 50% reduction in SRF from baseline). The primary outcome measure was the resolution of SRF, and various OCT biomarkers like central macular thickness (CMT), pigment epithelial detachments (PED), double-layer sign, elongation of the photoreceptor's outer segment, the integrity of the external limiting membrane, the integrity of the ellipsoid zone, hyperreflective foci in the outer segment, and subretinal deposits in the SRF were assessed. The mean age was 41.33 ± 10.75 years, and 34 participants were male. Thirty-seven (88.1%) of the participants had good responses to eplerenone, with the mean height of SRF decreasing significantly from a maximum of 269.74 µm to a minimum of 21.86 µm at six months (p<0.001). The mean CMT decreased from the first visit time point to the third visit time (p<0.001). Logistic regression analysis assessed the absence of PED and double-layer signs associated with a good response. The eplerenone therapy seems to be efficient for chronic CSCR, and OCT can be an invaluable aid to the treating physician.

Microperimetry and Structural Risk Factors on OCT in Intermediate Age-Related Macular Degeneration

PurposeTo determine the relationship between structural biomarkers on optical coherence tomography (OCT) that increases the risk of disease progression and microperimetric retinal sensitivity in patients with intermediate age-related macular degeneration (iAMD) DesignProspective cross-sectional, observational study ParticipantsForty-five eyes of 23 patients with iAMD MethodsPatients underwent OCT and microperimetry. OCT scans were evaluated for the risk factors intraretinal hyperreflective foci (HRF), hyporeflectivity within drusenoid lesions (HRDL), subretinal drusenoid deposits (SDD), double layer sign (DLS) and drusen volume. Microperimetric retinal sensitivity was analyzed with a 33-point grid covering the macula. With a novel method of determining what part of the retina corresponded to each microperimetry point, a Voronoi diagram was constructed, dividing the macula in cells consisting of the region nearer to each point than any other. The Voronoi diagram was superimposed on the OCT making it possible to determine the point-to-point location of the OCT risk factors. Univariable and multivariable linear mixed effects models were used for analysis Main Outcome MeasuresAssociation between microperimetric retinal sensitivity and OCT risk factors at individual measuring points Results1479 points of retinal sensitivity and corresponding structural area on OCT were included in this study. Retinal sensitivity was significantly decreased with presence of the OCT risk factors HRF, HRDL, DLS and drusen volume (all P < 0.001) when analyzed with the univariable linear mixed effects model. The multivariable model showed a significant decrease of retinal sensitivity with presence of HRF (P < 0.001), DLS (P = 0.025) and greater drusen volume (P < 0.001) ConclusionPresence of HRF, DLS, and greater drusen volume, all of which increase the risk of disease progression, are significantly and independently associated with decreased microperimetric retinal sensitivity in patients with iAMD.

Double Layer Sign and Pigment Epithelial Detachment in Patients Treated with Subthreshold Laser for Central Serous Chorioretinopathy

Background and Objective Central serous chorioretinopathy (CSCR) is characterized by serous detachments of the central neurosensory retina. Besides, other alterations of the retinal pigment epithelium (RPE) of the focal detachment of the RPE can occur. We explored the frequency of RPE detachment and double layer sign in OCT in our patient population, the influence of subthreshold photocoagulation (ST-LP) on these parameters and the possibility of correlations with visual acuity. Materials and Methods We conducted a retrospective analysis of all patients who underwent ST-LP based on the diagnosis of CSCR in a German university eye clinic from 2009 to 2014. Measurements in OCT were performed regarding pigment epithelial detachment (PED) and double layer sign (DLS). Results 54 eyes of 49 patients were included in the study. The frequency of PEDs dropped from 66% of cases at baseline to 50% after 3 months. No significant differences in calculated areas of lift-off volume of PED were identified. The frequency of a DLS was significantly lower 8 weeks after ST-LP compared to baseline (63%, p&lt;0.05), but not after 12 weeks. Conclusion We conclude that PEDs and DLS are common in CSCR. In this study, no convincing correlation can be identified between BCVA before ST-LP or at the last visit and different characteristics of PED as well as DLS. While the area of PED becomes smaller after ST-LP, the extent of the DLS seems to increase. Further prospective studies are required, and DLS with respect to the occurrence of CNV should also be given attention.

OCT risk factors for 2-year foveal involvement in non-treated eyes with extrafoveal geographic atrophy and AMD

PurposeTo assess the relationship of optical coherence tomography (OCT) findings and progression to foveal atrophy in a cohort of eyes with extrafoveal geographic atrophy (GA) and age-related macular degeneration (AMD) at inclusion.MethodsWe retrospectively analyzed 45 participants (45 eyes) with extrafoveal GA at baseline and with 2 years of regular follow-ups. Several OCT qualitative features (i.e., presence of foveal flat pigment epithelium detachment with a thin double layer sign [DLS] and reticular pseudodrusen, GA focality) and quantitative measurements (outer retinal layer thickness, retinal pigment epithelium [RPE] to Bruch’s membrane [BM] volume, minimum distance from the central foveal circle, and untransformed GA lesion size area) were assessed at baseline. Logistic regression analyses were carried out to identify independent significant predictors and compute odds ratios (ORs) for the risk of the development of atrophy.ResultsAt month 24, 26 eyes (57.8%) developed atrophy in the foveal central circle, while 11 eyes (24.4%) developed atrophy in the foveal central point. Significant independent predictive features for the development of atrophy in the foveal central circle included foveal outer retinal thickness (OR, 0.867; p = 0.015), minimum distance from the foveal central circle (OR, 0.992; p = 0.022), and foveal thin DLS (OR, 0.044; p = 0.036). The only independent predictive feature for the development of atrophy in the foveal central point was the presence of foveal thin DLS (OR, 0.138; p = 0.017).ConclusionsWe identified OCT risk factors for 2-year foveal atrophy in eyes with untreated extrafoveal GA at baseline.

Differences between young and elderly polypoidal choroidal vasculopathy patients with and without pachychoroid phenotypes.

To investigate the distinct characteristics between young and elderly polypoidal choroidal vasculopathy (PCV) patients based on the pachy- or non-pachychoroid phenotypes. PCV patients treated with intravitreal injections of Conbercept based on the 3 + PRN regimen from 27 centers of China PCV Research Alliance were included. Patients were categorized into the young and the elderly aged group based on the cut-off point determined using the Youden method according to the pachychoroid phenotypes. The characteristics of past medical history, lifestyle factors, fundus manifestations, and treatment response between the subgroups were analyzed. Three hundred eight eligible patients were included. Multivariate logistic regression showed a significant association between age and PCV subtype classification (OR = 0.921, P = 0.002). A cutoff age of 64.5 effectively distinguished between pachychoroid PCV and non-pachychoroid PCV (P < 0.001). Elderly PCV patients had a higher incidence of hypertension history (P = 0.044) but a lower incidence of diabetes history (P = 0.027). In terms of lifestyle, smoking history (P = 0.015) and staying up late (P = 0.004) were more significant in the young group of PCV patients. For clinical characteristics, the proportion of hemorrhagic PCV in the young group was significantly higher (P = 0.038), with a higher proportion of sharp-peaked PED (P = 0.049), thicker choroid (P < 0.001) but a lower portion of double-layer sign (P = 0.023) in OCT. Both groups showed significant anatomical changes compared to baseline in each follow-up period (P < 0.05), with the young group having a higher proportion of good anatomical response after the first injection (P = 0.009). PCV patients stratified by subtype exhibit distinct characteristics between the young and elderly groups.

Chronic Central Serous Chorioretinopathy in Elderly Subjects: Structure and Blood Flow Characteristics of Retina and Choroid.

With advancements in imaging technology, researchers have been able to identify more distinctive imaging features of central serous chorioretinopathy (CSC). However, existing research primarily concentrates on young patients aged 50years and below, leaving a dearth of studies on elderly CSC patients. Previous studies indicate that elderly CSC patients may exhibit unique imaging characteristics and have a clinical prognosis that significantly differs from younger patients. This study aimed to evaluatethe characteristics of retina, choroid structure, and blood flow in elderly patients with chronic CSC (cCSC) examined multimode imaging and try to find new pathogenesis information of it. Using a cut-off age of 50years, patients with chronic central serous chorioretinopathy were divided into two groups: older and younger. The control group consisted of 40 healthy individuals, with their right eyes assigned. Various clinical features were recorded, including the incidence of ellipsoid zone rupture (EZ-), fibrin in the subretinal fluid (SRF), pachydrusen, subretinal drusenoid deposits (SDD), pigment epithelial detachment (PED), double-layer sign (DLS), and choroidal lipid globule cavern. Measurements were taken for the thickness of the outer nuclear layer (ONL), the length of the extended outer photoreceptor segment (POS), the height and width of SRF, the vascular density of each layer of the retinal capillary plexus, the central macular thickness (CMT), and the subfoveal choroidal thickness (SFCT). The proportion of females in the elderly group (43.75%) was significantly higher than that in the youth group (22.41%) (p = 0.034). The degree of hyperopia in the elderly group (1.03 ± 0.73) was higher than that in the youth group (0.26 ± 1.06), with a significant difference in BCVA (p = 0.05). The thickness of SFCT, CMT, ONL in the elderly group, and the length of photoreceptor outer segment in the elderly group were thinner than those in the youth group (p < 0.05). Choroidal capillary perfusion area (CCPA), macular area, and paramacular area were lower in the elderly group than those in the youth group in the full scan range (p < 0.05). The blood flow densities of deep capillary plexus (DCP), intermediate capillary plexus (ICP), and superficial capillary plexus (SCP) in the whole scan range, macular area, and paramacular area were lower in the elderly group than in the youth group, but the differences were not statistically significant. In conclusion, our data suggest that elderly patients with cCSC may experience different disease outcomes. Elderly cCSC patients exhibit less gender bias, poorer vision, more severe structural damage and ischemia in the choroid and retina, and have a higher risk of developing choroidal neovascularization.

The Double Layer Sign Is Highly Predictive of Progression to Exudation in Age-Related Macular Degeneration

The presences of a double layer sign (DLS) and a shallow irregular retinal pigment epithelium (RPE) elevation (SIRE) were investigated using spectral domain-OCT (SD-OCT) imaging to determine their ability to predict progression to exudative macular neovascularization (eMNV) in the unaffected fellow eyes (study eye) of participants with age-related macular degeneration (AMD) with newly diagnosed unilateral eMNV. Retrospective, reanalysis of SD-OCT scans of study eyes from the Early Detection of Neovascular AMD (EDNA) study with 3 years follow-up (FU). The EDNA study repository of SD-OCT scans was assessed for inclusion. Cases with incomplete data sets, low quality scans, or exhibiting other pathology were excluded, which resulted in 459 eligible cases. Spectral domain-OCT volume scans of study eyes were graded for irregular elevation of the RPE (IE), with length, and height measurements made on the most affected B-scan. Eyes with heterogeneous reflectivity within the IE were classified as exhibiting the DLS. Eyes with DLS where the length of separation between RPE and Bruch's membrane was ≥ 1000 μm in length and < 100 μm in height were subclassified as SIRE. Hazard of progression to eMNV for DLS and SIRE. Of the 459 eyes, 268 had IE, of which 101 were DLS-like and 51 also fulfilled criteria for SIRE. Over the 3 years FU period, 104 (23%) eyes progressed to eMNV. After an FU of 18 months, a significantly higher proportion of study eyes (P < 0.001) with IE, DLS, and SIRE developed eMNV compared with those without these features (IE: 17% vs. no IE 6.3%; DLS: 23% vs. no DLS 9.9%; SIRE: 22% vs. no SIRE 11%). In the adjusted Cox regression models, a significantly greater hazard of progression (P < 0.001) was associated with the presence of IE (adjusted hazard ratio [HR], 3.01; 95% confidence interval [CI], 1.88-4.82), DLS (adjusted HR, 3.41; 95% CI, 2.26-5.14), or SIRE (adjusted HR, 2.83; 95% CI, 1.68-4.75). The DLS is a highly sensitive predictor of progression to eMNV, and the use of SIRE does not improve predictability. Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Correlation of the OCT Double-Layer Sign with Type 1 Non-Exudative Neovascularization on OCT-A in Age-Related Macular Degeneration.

Background and Objectives: Early diagnosis of the exudative form of age-related macular degeneration (AMD) is very important for a timely first treatment, which is directly related to the preservation of functional visual acuity over a long period. The goal of this paper was to examine the correlation between the double-layer sign (DLS) and the presence of non-exudative macular neovascularization (MNV). Materials and Methods: Our research included 60 patients with AMD, exudative in one eye and non-exudative in the other eye. We analyzed only the non-exudative form using optical coherence tomography (OCT) and optical coherence tomography angiography (OCT-A). The patients were classified into three groups, depending on the duration of the disease (<2 years, 2 to 5 years, >5 years). The onset of the disease was deemed the moment of establishing a diagnosis of exudative AMD in one eye. We defined the presence or absence of a DLS using OCT and the presence of non-exudative MNV using OCT-A, both on 3 × 3 mm and 6 × 6 mm sections. DLS was used as a projection biomarker for non-exudative MNV, with the aim of establishing a rapid diagnosis and achieving early treatment of the disease. Results: We found that there was a statistically significant correlation between the DLS diagnosed using OCT and non-exudative MNV diagnosed by OCT-A for both 3 × 3 mm (p < 0.001) and 6 × 6 mm (p < 0.001) imaging. There was a statistically significant difference between the frequencies of both DLS and MNV in Groups I and III on both 3 × 3 and 6 × 6 mm imaging. A statistically significant difference was also noted in the frequencies of DLS and MNV on 6 × 6 mm imaging, but not on 3 × 3 mm imaging, between Groups I and II. No differences were found between the frequencies of DLS and MNV between Groups II and III. Conclusions: The DLS on OCT can be used as a projection biomarker to assess the presence of a non-exudative MNV.

Aneurysmal type 2 neovascularization: A new entity

To report three cases of aneurysmal type 2 neovascularization (AT2), a novel entity within the pachychoroid disease (PD) spectrum. We conducted an observational retrospective study of three patients with subretinal polyps treated with intravitreal aflibercept. We reviewed clinical and imaging data of the three patients. Best corrected visual acuity (BCVA), central macular thickness (CMT), choroidal subfoveal thickness, choroidal thickness under the polyps and the presence of a dry macula were assessed at baseline and throughout the follow-up. All of the patients showed granular hypoautofluorescence on fundus autofluorescence. Indocyanine green angiography revealed prominent hyperfluorescent branching vascular networks ending in multiple aneurysmal dilatations. Optical coherence tomography (OCT) demonstrated that the aneurysmal lesions were localized in the subretinal space. Additionally, OCT showed retinal pigment epithelial microtears, the double-layer sign and pachyvessels. En face OCT-A perfectly defined prominent telangiectatic branching vascular networks in all the patients, but only revealed polyps in two out of the three patients. Cross-sectional OCT-A demonstrated polyps as patchy circular hypoflow signals in each case. After the intravitreal treatment, BCVA remained unimproved in all of the patients, despite decreased CMT and achievement of a dry macula, as a result of the development of subretinal fibrosis. In summary, we describe a new entity within the spectrum of PD, which we have termed AT2. This novel disease is characterized by the presence of aneurysmal dilatations in the subretinal space, along with the typical features of PD, such as choroidal vascular hyperpermeability, thickening of the choroid and pachyvessels.

Risk factors for perioperative hidden blood loss after one-segment posterior circumferential decompression surgery on thoracic ossification of the posterior longitudinal ligament: a finding of the double-layer sign on CT

BackgroundHidden blood loss (HBL) is of increasing interest to spine surgeons. This retrospective study aimed to evaluate perioperative HBL and its risk factors in patients undergoing one-segment posterior circumferential decompression surgery on thoracic ossification of the posterior longitudinal ligament (T-OPLL).MethodWe retrospectively studied 112 patients diagnosed with T-OPLL following posterior circumferential decompression surgery from August 2015 to June 2020. Patient demographics, blood loss-related parameters, surgery-related data and imaging parameters were extracted. Postoperative complications were also recorded. Pearson or Spearman correlation analysis was used to investigate the correlation between patient demographics and HBL. Multivariate linear regression analysis was performed to determine the independent risk factors associated with HBL.ResultsForty-five men and 67 women were involved in this research, with an average age of 56.4 ± 10.2 years. The mean HBL was 459.6 ± 275.4 ml, accounting for 56.5% of the total blood loss. Multiple linear regression analysis showed that double-layer sign (P = 0.000), ossification occupancy ratio (OOR) > 60% (P = 0.030), age (P = 0.010), hematocrit (Hct) loss (P = 0.034), and postoperative Hct (P = 0.016) were independent risk factors for HBL. However, OPLL morphology (P = 0.319), operation time (P = 0.587), hemoglobin (Hb) loss (P = 0.644), and postoperative Hb (P = 0.952) were not significantly different from HBL.ConclusionA high proportion of HBL was found after posterior circumferential decompression surgery on T-OPLL during the perioperative period, which should not be overlooked. Double-layer sign, OOR > 60%, age, Hct loss and postoperative Hct are independent risk factors for HBL.

Changes of microstructure of central serous chorioretinopathy on OCT and its relationship with prognosis

PurposeTo quantitatively evaluate the relationship between retinal microstructure and prognosis in patients with central serous chorioretinopathy(CSC) using optical coherence tomography(OCT). MethodsThree hundred and ninty-eight affected eyes of patients with central serous chorioretinopathy were included in this retrospective study. The OCT images of all patients were analyzed in baseline, and logistic regression analysis were performed with 11 independent variables, and subretinal fluid absorption in 3 months after therapy as dependent variable. The correlation between shortage of ellipsoid baseline and height of foveal subretinal fluid, width of foveal subretinal fluid were analyzed respectively. The difference of duration and baseline logMAR visual acuity in eyes with and without double layer sign or subretinal hyper-reflective materials were analyzed respectively. The difference of therapeutic outcome among different therapeutic methods was also analyzed in eyes with double-layer sign and subretinal hyper-reflective materials respectively. ResultsIn the regression analysis with subretinal fluid absorption in 3 months after therapy as dependent variable, disintegrity of ellipsoid zone was statistically significant(P<0.0001,B=1.288). There is no correlation between disintegrity of the ellipsoid zone and the width or height of subretinal fluid. The duration of disease in eyes with double layer sign or subretinal hyper-reflective materials was longer than those without these features(P<0.001, P<0.0001). In the eyes with the double-layer sign or subretinal hyper-reflective material, the difference of logMAR visual acuity 3 months after treatment between 2 therapeutic methods was not statistically significant. ConclusionsUsing optical coherence tomography to evaluate microstructure changes in eyes with central serous chorioretinopathy quantitatively, we found that subretinal fluid was easier to absorb completely in eyes with less disintegrity of ellipsoid zone. Double layer sign and subretinal hyper-reflective materials are more common in eyes with longer duration of disease.

OPTICAL COHERENCE TOMOGRAPHY AND OCT ANGIOGRAPHY CHARACTERISTICS OF INDOCYANINE GREEN ANGIOGRAPHIC PLAQUES IN NONEXUDATIVE AGE-RELATED MACULAR DEGENERATION.

To describe characteristics of indocyanine green (ICG) angiographic plaques in the nonexudative fellow eye of White patients with unilateral treatment-naïve exudative neovascular age-related macular degeneration through optical coherence tomography (OCT) and OCT angiography (OCTA). In this retrospective cross-sectional study, nonexudative eyes with ICG angiographic plaques were analyzed by OCT B-scans for the sensitivity of a double-layer sign, a pigment epithelium detachment, outer retinal atrophy, hyperreflective dots, and subretinal hyperreflective material (SRHM). The ICG angiographic plaque was matched with a macular neovascularization in OCTA en face scans and color-coded B scans. In total, 35 ICG angiographic plaques in 33 of 291 (11%) nonexudative eyes were diagnosed. OCT revealed 27 double-layer sign (78%), eight pigment epithelium detachment (23%), 8 outer retinal atrophy (23%), eight hyperreflective dots (23%), and one subretinal hyperreflective material (3%). OCTA confirmed a macular neovascularization in 28 plaques (80%): 7 (20%) in en face scans, 3 (9%) in color-coded B scans, and 18 (51%) in both. The area size in OCTA was significantly smaller than that of ICG angiography ( P = 0.002). The diagnosis of an ICG angiographic plaque in nonexudative fellow eyes of Whites with unilateral treatment-naïve exudative neovascular age-related macular degeneration was highly suggestive of a typical macular neovascularization type 1 as characterized by OCT and OCTA.

Detection of Nonexudative Macular Neovascularization on Structural OCT Images Using Vision Transformers.

A deep learning model was developed to detect nonexudative macular neovascularization (neMNV) using OCT B-scans. Retrospective review of a prospective, observational study. Normal control eyes and patients with age-related macular degeneration (AMD) with and without neMNV. Swept-source OCT angiography (SS-OCTA) imaging (PLEX Elite 9000, Carl Zeiss Meditec, Inc) was performed using the 6× 6-mm scan pattern. Individual B-scans were annotated to distinguish between drusen and the double-layer sign (DLS) associated with the neMNV. The machine learning model was tested on a dataset graded by humans, and model performance was compared with the human graders. Intersection over Union (IoU) score was measured to evaluate segmentation network performance. Area under the receiver operating characteristic curve values, sensitivity, specificity, and positive predictive value (PPV) and negative predictive value (NPV) were measured to assess the performance of the final classification performance. Chance-corrected agreement between the algorithm and the human grader determinations was measured with Cohen's kappa. A total of 251 eyes from 210 patients, including 182 eyes with DLS and 115 eyes with drusen, were used for model training. Of 125 500 B-scans, 6879 B-scans were manually annotated. A vision transformer segmentation model was built to extract DLS and drusen from B-scans. The extracted prediction masks from all B-scans in a volume were projected to an en face image, and an eye-level projection map was obtained for each eye. A binary classification algorithm was established to identify eyes with neMNV from the projection map. The algorithm achieved 82%, 90%, 79%, and 91% sensitivity, specificity, PPV, and NPV, respectively, on a separate test set of 100 eyes that were evaluated by human graders in a previous study. The area under the curve value was calculated as 0.91 (95% confidence interval, 0.85-0.98). The results of the algorithm showed excellent agreement with the senior human grader (kappa= 0.83, P < 0.001) and moderate agreement with the junior grader consensus (kappa= 0.54, P < 0.001). Our network (code is available at https://github.com/uw-biomedical-ml/double_layer_vit) was able to detect the presence of neMNV from structural B-scans alone by applying a purely transformer-based model.