Internal limiting membrane separation and posterior vitreous hyperreflective dots: novel OCT findings in Purtscher-like retinopathy.

BACKGROUND: Purtscher or Purtscher-like retinopathy is diagnosed by retinal hemorrhages and areas of retinal whitening on fundus examination, as well as a reduction in visual acuity due to microvascular occlusion of the precapillary retinal arterioles. We describe novel optical coherence tomography (OCT) findings of internal limiting membrane (ILM) separation and posterior hyperreflective dots in a case of Purtscher-like retinopathy in this report. METHODS: A 33-year-old man with acute pancreatitis and alcohol-induced liver disease presented to the retina department complaining of four days of painless vision loss in both eyes. Both eyes' anterior segment examination and intraocular pressure were normal. Dilated fundus examination of both eyes revealed confluent areas of retinal whitening, hemorrhages, and cotton-wool spots over the posterior pole, indicating Purtscher-like retinopathy. OCT scans through the macula revealed dense inner retinal reflectivity, thickening, and loss of retinal layer stratification, as well as outer retinal layer shadowing and islands of ILM separation, posterior vitreous hyperreflective dots, and minimal subfoveal fluid, all of which corresponded to areas of retinal whitening on fundus photographs. The patient was given a brief course of systemic steroids. RESULTS: On the tenth day after the presentation, visual acuity in the right eye had improved to 6/18 and finger counting at 1 m in the left eye. The retinal findings had faded. The retina had reverted to its normal thickness on the OCT scans, with minimal hyperreflectivity remaining. The ILM separation and posterior vitreous hyperreflective dots were no longer present. CONCLUSION: Following Purtscher or Purtscher-like retinopathy, we believe inflammation could play a major role in the development of these two novel OCT findings. This case offers an additional perspective on the underlying mechanisms responsible for the retinal manifestations observed in Purtscher or Purtscher-like retinopathy.

[Widefield optical coherence tomography as an effective method for detecting imperceptible flap retinal tears (clinical observation)]. / Shirokopol'naya opticheskaya kogerentnaya tomografiya ­ effektivnyi metod vyyavleniya klapannogo razryva setchatki (klinicheskoe nablyudenie).

Certain late peripheral ruptures after acute posterior vitreous detachment (PVD) may remain undetected during the initial examination of the fundus due to the presence of vitreous hemorrhages and other factors, but they can lead to rhegmatogenic retinal detachment in the future. Hence, it is necessary to conduct an additional thorough examination using optical coherence tomography (OCT) of the vitreoretinal interface periphery in the presence of tear predictors: retinal and vitreal hemorrhages, vitreous pigment cells ("tobacco dust") in the anterior segment of the vitreous body, as well as hyper-reflective dots ("starry sky") in the vitreous body according to OCT scans of patients with acute symptomatic detachment of the hyaloid membrane. The article presents the case of a patient with a clinically imperceptible flap tear detected during acute posterior vitreous detachment. Widefield OCT of the vitreoretinal interface was performed by "sliding" from the center to the periphery of the retina, and revealed a flap tear located next to a dot retinal hemorrhage. OCT scanning of the retinal periphery is an effective modern diagnostic method in the ophthalmological clinical practice.

Predictive capacity of baseline hyperreflective dots on the intravitreal dexamethasone implant (Ozurdex®) outcomes in diabetic macular edema: a multicenter study.

PURPOSE: The purpose of this study is to evaluate the predictive capacity of the baseline hyperreflective dots (HRDs) on the functional and anatomical response in patients with diabetic macular edema (DME). Additionally, we assessed the impact of the intravitreal dexamethasone (DEX) implant on the functional and anatomic outcomes. METHODS: Retrospective, multicenter study. The number of HRDs was graded in four different stages: [A] none HRDs; [B] few, 1-10 HRDs; [C] moderate, 11-20 HRDs; and [D] many, ≥ 21 HRDs. For statistical purposes, groups A and B were combined [scarce HRDs (S-HRDs)] and group D was renamed as [abundant HRDs (A-HRDs)]. The primary endpoints were the mean change in best corrected visual acuity (BCVA) and central macular thickness (CMT) according to baseline HRD stage. RESULTS: One hundred eyes from one hundred patients were included in the study. Mean BCVA significantly improved from 52.9 (50.0 to 55.8) letters ETDRS at baseline to 57.2 (54.0 to 60.4) letters at month 6, p = 0.0039. There were no significant differences between the S-HRDs and A-HRD study groups in BCVA. As compared to baseline, CMT reduction was 106.3 (59.8 to 152.7) µm and 94.2 (34.7 to 153.7) µm in S-HRDs and A-HRD groups, respectively (p < 0.0001 each, respectively). Twenty-three (65.7%) and 18 (62.1%) eyes achieved a CMT reduction ≥ 10% in the S-HRD and A-HRD groups, respectively, p = 0.7640. DEX implant significantly reduced the presence of outer nuclear layer (ONL) disruptions (p = 0.0010). CONCLUSIONS: The number of HRDs did not influence either functional or anatomic outcomes. DEX implant significantly decreases the number of eyes with ONL disruptions, which might improve retinal integrity.

Outer Retinal Hyperreflective Dots: A Potential Imaging Biomarker in Rhegmatogenous Retinal Detachment.

PURPOSE: To investigate hyperreflective dots (HRDs) on baseline OCT in rhegmatogenous retinal detachment (RRD). DESIGN: Retrospective cohort study. SUBJECTS: Consecutive primary fovea-off RRDs presenting between January 2012 and September 2022. METHODS: Visual acuity (VA) was obtained at baseline, 3, 6, and 12 months. Baseline foveal OCT scans were graded for the presence of HRDs in the outer retina, morphologic stage of RRD in the parafovea, and foveal photoreceptor integrity (intact, patchy or complete loss of the bacillary layer). Epiretinal membrane (ERM) and cystoid macular edema (CME) were graded after surgery. MAIN OUTCOME MEASURES: The primary outcome was the proportion of patients in each morphologic stage with HRDs present on OCT and their association with postoperative VA. Secondary outcomes included association with the height of foveal detachment, duration of central vision loss, RRD extent, and development of ERM/CME. RESULTS: A total of 351 patients were included. The presence of HRDs by morphologic stage of RRD was 0% in stage 1, 4.5% (2/42) in stage 2, 13% (7/54) in stage 3a, 16% (20/126) in stage 3b, 48% (40/83) in stage 4, and 85% (35/41) in stage 5. Hyperreflective dots were associated with increasing stage of RRD (P < 0.001), reduced integrity of foveal photoreceptors (P < 0.001), and reduced postoperative VA at 3, 6, and 12 months (P < 0.001), after excluding visually significant cataracts and adjusting for covariates. There was also a significant association between HRDs and height of foveal detachment, duration of central vision loss, and RRD extent (P < 0.001). Hyperreflective dots were neither associated with postoperative ERM formation nor with its severity (P = 0.27). Nevertheless, they were associated with the occurrence of CME at 3 and 6 months after surgery (P = 0.01; P = 0.006). CONCLUSIONS: Hyperreflective dots have been hypothesized to consist of intraretinal inflammatory cells. We found that HRDs were significantly associated with the morphologic stage, extent, duration, and height of the RRD before surgery and with reduced VA and CME after surgery. Our results suggest that HRDs are associated with photoreceptor degeneration, as longstanding and extensive RRDs are more likely to present with HRDs. The association of HRDs with CME provides insight into the possible importance of inflammatory processes in RRD before and after surgery. FINANCIAL DISCLOSURE(S): The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Hyper-reflective vitreous spots in central retinal artery occlusion: An unusual finding in two cases.

PURPOSE: To present two consecutive cases of Central Retinal Artery Occlusion (CRAO) with unusual Optical Coherence Tomography (OCT) presentation of Hyperreflective Spots (HRS) in the posterior vitreous. CASE REPORT: The first patient was a 59 years-old male who developed CRAO in the post-operative period after aortic valve replacement. OCT scans revealed the presence of many HRS in the posterior vitreous, remarkably decreased in number at two months follow-up. The second patient was a 74-year-old male who developed CRAO after arterial chemoembolization for recurrent hepatocellular carcinoma. OCT scans showed again the presence of hyperreflective spots in the posterior vitreous and their reduction at two months follow-up with inner retinal atrophy as the final outcome in both cases. CONCLUSIONS: HRS in the posterior vitreous have been described in inflammatory eye conditions such as uveitis, diabetic macular edema, post cataract surgery, and considered a clinical sign of inflammation. To our knowledge, the combination of CRAO and HRS has not been previously reported. The number of HRS seems to decrease over time, suggesting a role for inflammatory response in the acute stage of CRAO. A similar pathogenic process is known to occur during cerebral ischemia, where the inflammatory response may exacerbate brain injury and post-ischemic damage.

Hyperreflective Dots on OCT as a Predictor of Treatment Outcome in Diabetic Macular Edema: A Systematic Review.

TOPIC: This review aims to evaluate the role of hyperreflective dots (HRDs), detected using OCT, as a predictor of the treatment outcome in patients with diabetic macular edema (DME). CLINICAL RELEVANCE: The treatment of DME is possible, but its results are often unsatisfactory. Thus, it is important to develop biomarkers that can help to predict the treatment response to optimize the treatment's effect for individual patients. METHODS: PubMed, Embase, Web of science, and Cochrane library were searched (final search date on May 5, 2021). Participants were patients diagnosed with DME and provided with treatment. The predictor was HRDs, detected using OCT, before treatment. The outcomes were best-corrected visual acuity (BCVA) and central macular thickness (CMT), detected using OCT, after treatment. Two reviewers independently screened the titles and abstracts as well as full text. The refined Quality in Prognosis Studies tool was used to assess the risk of bias for each included study. Because of the clinical heterogeneity of the studies, a meta-analysis was not performed. RESULTS: Thirty-six studies were included. The Quality in Prognosis Studies assessment showed that most studies had a low or moderate risk of bias in 6 domains. Six studies could not find any correlation between baseline HRDs (either the presence or absence of HRDs [n = 1] or baseline HRD number [n = 5]) and outcome (BCVA or CMT), whereas 12 studies found a significant correlation between these variables. Eight studies reported that baseline HRDs could predict a poor visual outcome (n = 4 on prescence or abscence of HRD and n = 4 on HRD number), and 4 studies (n = 1 on prescence or abscence of HRD and n = 3 on HRD number) found that HRDs were predictive of visual improvement. Fifteen out of 17 studies found that the HRD number decreased after treatment. CONCLUSION: Based on the current literature, the HRD numbers decrease with treatment, but it is not clear whether HRDs predict the treatment outcome in patients with DME. Future investigations with more uniform approaches are needed to confirm the nature of this biomarker and its effect on DME treatment outcome.

Characterization of Hyperreflective Dots by Structural and Angiographic Optical Coherence Tomography in Patients with Diabetic Retinopathy and Healthy Subjects.

Hyperreflective dots are a common but highly variable feature of optical coherence tomography (OCT) scans of the retina. We studied the spatial characteristics and perfusion of hyperreflective dots using both structural and angiographic OCT B-scans of the macula in 16 eyes in 8 healthy subjects and 8 patients with diabetic retinopathy without macular edema. Hyperreflective dots were manually graded in a 1000 µm parafoveal area by number, diameter, location and perfusion status and traced through adjacent B-scans at 11 µm intervals to determine their length. Thereby, this study defined a procedure to identify granular and elongated hyperreflective elements and differentiate between presumably perfused and occluded capillaries. The latter were only found in the diabetic patients. This classification can potentially be automated to non-invasively identify capillary non-perfusion in vivo.

Automatic segmentation of hyperreflective dots via focal priors and visual saliency.

PURPOSE: Hyperreflective dots (HRDs) can be observed in spectral domain optical coherence tomography (SD-OCT), which can provide a sensitive marker in the treatment decision process. Quantitative analyses of HRDs are the key to make appropriate decisions on observation, treatment, and retreatment. The purpose of this study is to automatically and accurately segment HRDs in SD-OCT B-scans with diabetic retinopathy (DR). METHODS: The authors propose an automatic segmentation algorithm of HRDs via focal priors and visual saliency. The algorithm is divided into three stages: segmentation of retinal layers, calculation of the multiscale local contrast saliency map, and adaptive threshold segmentation. First, a method based on improved graph search is used to segment retinal layers to obtain the region of interest (ROI) and the reflectivity estimation of the retinal pigment epithelium (RPE) layer; then, the multiscale local contrast saliency map is obtained by using a local contrast measure, which measures the dissimilarity between the current pixels and corresponding neighborhoods; finally, an adaptive threshold is applied to segment HRDs. RESULTS: Experimental results on 20 SD-OCT B-scans demonstrate that our method is effective for HRDs segmentation. The average dice similarity coefficient (DSC) and detection accuracy are 71.12% and 85.07%, respectively. CONCLUSIONS: The proposed method can accurately segment HRDs in SD-OCT B-scans with DR and outperforms current state-of-the-art methods. Our method can provide reliable HRDs segmentation to assist ophthalmologists in clinical diagnosis, treatment, disease monitoring, and progression.

Algorithm for Detection and Quantification of Hyperreflective Dots on Optical Coherence Tomography in Diabetic Macular Edema.

Purpose: To develop an algorithm to detect and quantify hyperreflective dots (HRDs) on optical coherence tomography (OCT) in patients with diabetic macular edema (DME). Materials and Methods: Twenty OCTs (each OCT contains 128 b scans) from 20 patients diagnosed with DME were included in this study. Two types of HRDs, hard exudates and small HRDs (hypothesized to be activated microglia), were identified and labeled independently by two raters. An algorithm using deep learning technology was developed based on input (in total 2,560 OCT b scans) of manual labeling and differentiation of HRDs from rater 1. 4-fold cross-validation was used to train and validate the algorithm. Dice coefficient, intraclass coefficient (ICC), correlation coefficient, and Bland-Altman plot were used to evaluate agreement of the output parameters between two methods (either between two raters or between one rater and proposed algorithm). Results: The Dice coefficients of total HRDs, hard exudates, and small HRDs area of the algorithm were 0.70 ± 0.10, 0.72 ± 0.11, and 0.46 ± 0.06, respectively. The correlations between rater 1 and proposed algorithm (range: 0.95-0.99, all p < 0.001) were stronger than the correlations between the two raters (range: 0.84-0.96, all p < 0.001) for all parameters. The ICCs were higher for all the parameters between rater 1 and proposed algorithm (range: 0.972-0.997) than those between the two raters (range: 0.860-0.953). Conclusions: Our proposed algorithm is a good tool to detect and quantify HRDs and can provide objective and repeatable information of OCT for DME patients in clinical practice and studies.

The Correlation between Hemoglobin A1c (HbA1c) and Hyperreflective Dots (HRD) in Diabetic Patients.

Hyperreflective dots (HRD) are activated retinal microglial cells induced by retinal inflammation in diabetic patients. This study was conducted to compare the HRD count of normal and diabetic subjects; to determine the correlation between hemoglobin A1c (HbA1c) levels and HRD count; to determine HbA1c cut-off levels for the appearance of HRD in diabetic patients. A cross-sectional study was conducted among normal and diabetic patients. Fundus photos, SD-OCT images and HbA1c levels were taken. A total of 25 normal subjects, 32 diabetics without retinopathy and 26 mild-to-moderate nonproliferative diabetic retinopathy (NPDR) diabetics were recruited. There was a statistically significant difference between the mean count of HRD among the normal group, the diabetic without retinopathy group and the mild-to-moderate NPRD group. The mean HRD count in the inner retina layer was significantly higher compared to the outer retina layer. There was a significant linear relationship between the HbA1c levels and HRD count. Using the receiver operating curve, the HbA1c level of 5.4% was chosen as the cut-off point for the appearance of HRD. The positive linear correlation between the HbA1c levels and the appearance of HRD may indicate that hyperglycemia could activate retina microglial cells in diabetic patients.

Effects of intravitreal conbercept before panretinal photocoagulation on lipid exudates in diabetic macular documented by optical coherence tomography.

AIM: To evaluate the effects of intravitreal conbercept (IVC) as adjunctive treatments before panretinal photocoagulation (PRP) to decrease hyperreflective dots (HRDs) in Chinese proliferative diabetic retinopathy (PDR) patients. METHODS: Fifty-nine enrolled patients were categorized into 2 groups: single dose IVC (0.5 mg/0.05 mL) 1wk before PRP (Plus group) or PRP only (PRP group). Six months later, we measured the best corrected visual acuity (BCVA), central macula thickness (CMT) by optical coherence tomography and counted the number of HRDs in different retina layers. RESULTS: The average CMT significantly decreased in Plus group but increased in PRP group. The average BCVA in the Plus group was also significantly better than that in the PRP group. Total HRDs decreased in the Plus group but increased in PRP group significantly. IVC pre-treatment has beneficial effects on reducing HRDs forming in the inner retina layer while the PRP alone increased the HRDs in the outer retina layer. CONCLUSION: IVC is a promising adjunctive treatment to PRP in the treatment of PDR. Single dose IVC one week before PRP is suggested to improve retina blood-retina barrier, decrease lipid exudate and inhibit HRDs development in PDR.

Evaluation of choroidal hyperreflective dots in acute and chronic central serous chorioretinopathy.

Purpose: To determine the association between hyperreflective dots (HRD) in the choroid and visual acuity and swept-source optical coherence tomography (SS-OCT)-derived structural parameters in central serous chorioretinopathy (CSC). Methods: SS-OCT images (single visit) of consecutive patients with CSC were evaluated for the presence of HRDs in the choroid using an automated algorithm and manual measurements of central macular and subfoveal choroidal thicknesses were obtained. Results: 61 eyes of 61 subjects were included in this retrospective study (32 subjects with acute and 29 with chronic CSC). Mean (± SD) choroidal HRD counts in acute and chronic CSC were 139.4 ± 29.9 and 124.9 ± 28.1, respectively (P = 0.04). In acute CSC, HRD was correlated with both age (P = 0.004) and subfoveal choroidal thickness (SFCT) (P = 0.016), but not with visual acuity or other OCT-derived measurements. In chronic CSC, HRD was correlated with central macular thickness (P = 0.011); neurosensory detachment height (P = 0.046); SFCT (P = 0.012). Considering all patients, the presence of HRDS was significantly negatively correlated with age (r = -0.401; P= 0.002) and SFCT (r = -0.332; P= 0.010). Conclusion: HRDs are correlated with both age and SFCT in acute CSC, and with CMT, height of neurosensory detachment and SFCT in chronic CSC. Development of HRDS is associated with the remodelling of chorioretinal structures as previously noted in CSC.

Outer Retinal and Choroidal Evaluation in Multiple Evanescent White Dot Syndrome (MEWDS): An Enhanced Depth Imaging Optical Coherence Tomography Study.

PURPOSE: To perform an analysis of optical coherence tomography (OCT) abnormalities in patients with MEWDS, during the acute and recovery stages, using enhanced depth imaging-OCT (EDI-OCT). METHODS: A retrospective case series of five patients with MEWDS was included. EDI-OCT imaging was evaluated to detect retinal and choroidal features. RESULTS: In the acute phase, focal impairment of the ellipsoid zone and external limiting membrane, hyperreflective dots in the inner choroid, and full-thickness increase of the choroidal profile were observed in the affected eye; disappearance of these findings and restoration of the choroidal thickness (p = 0.046) was appreciated in the recovery phase. No OCT abnormalities were assessed in the unaffected eye. CONCLUSIONS: EDI-OCT revealed transient outer retinal layer changes and inner choroidal hyperreflective dots. A transient increased thickness of the whole choroid was also identified. This might confirm a short-lasting inflammatory involvement of the whole choroidal tissue in the active phase of MEWDS.

The causes of hyperreflective dots in optical coherence tomography excluding diabetic macular edema and retinal venous occlusion§.

PURPOSE: To investigate the causes of hyperreflective dots (HRDs) in spectral domain optical coherence tomography (OCT) excluding diabetic macular edema (DME) and RVO (retinal vein occlusion). PATIENTS AND METHODS: The medical records of 56 patients with HRDs documented by OCT were reviewed retrospectively. The patients with DME and RVO were excluded from the study in order to prevent misdiagnosing hard exudates or HRDs. The causes, unilaterality or bilaterality of HRD and demographic properties of the patients with HRD were evaluated. RESULTS: Sixty four eyes of 56 patients having HRDs were included in this study. Of the patients with HRD, 17 (30.36%) were women and 39 (69.64%) were men. The ages of patients were between 13 to 84 years (median 60.18 years). The causes of HRD were as follows: papilledema in 4 eyes (6.25%), active neovascular age related macular degeneration (AMD) in 33 eyes (51.56%), familial dominant drusen in 2 eyes (3.13%), central serous chorioretinopathy in 19 eyes (29.69%) and commotio retina in 2 eyes (3.13%), choroidal folds in one eye (1.56%), branch retinal artery occlusion in one eye (1.56%), central retinal artery occlusion in one patient (1.56%) and Best vitelliform macular dystrophy in one eye (1.56%). The most common cause of HRD was AMD. The causes of HRDs in both eyes were AMD and papilledema. CONCLUSION: The most common causes of HRDs excluding DME and RVO seem as active exudative AMD. The presence of HRDs in retinal diseases might affect the decisions and the results of the treatment and the prognosis of diseases.