Multimodal Imaging of Multiple Evanescent White Dot Syndrome: A New Interpretation

Comprehensive insights into COVID-19 vaccine-associated multiple evanescent white dot syndrome (MEWDS): A systematic analysis of reported cases

Considering the widespread use of COVID-19 vaccines as a preventive measure against the spread of the virus, it's necessary to direct attention to the adverse effects associated with vaccines in a limited group of populations. Multiple evanescent white dot syndrome (MEWDS) following COVID-19 vaccination is a rare adverse reaction associated with COVID-19 vaccines. In this systematic review, we collected 19 articles with 27 patients up to November 1, 2023, summarizing the basic information, clinical manifestations, examinations, treatments, and recoveries of the 27 patients. The 27 enrolled patients (6 males, 21 females) had a median age of 34.1 years (15-71 years old) and were mainly from 5 regions: Asia (8), the Mediterranean region (8), North America (7), Oceania (3) and Brazil (1). Symptoms occurred post-first dose in 9 patients, post-second dose in 14 (1 with symptoms after both), post-third dose in 1, and both post-second and booster doses in 1, while details on 2 cases were not disclosed. Treatments included tapered oral steroids (6), topical steroids (3), tapered prednisone with antiviral drugs and vitamins (1), and valacyclovir and acetazolamide (1), while 16 received no treatment. All patients experienced symptom improvement, and nearly all patients ultimately recovered. Moreover, we summarized possible hypotheses concerning the mechanism of COVID-19 vaccine-associated MEWDS. The findings provide insights into the clinical aspects of COVID-19 vaccine-associated MEWDS. More attention should be given to patients with vaccine-associated MEWDS, and necessary treatment should be provided to patients experiencing a substantial decline in visual acuity to improve their quality of life.

An update of multimodal imaging in white dot syndrome

The white dot syndromes are a group of phenotypically similar disorders characterized by multiple lesions at the level of the outer retina, retinal pigment epithelium, and choroid. Common white dot syndromes whose imaging modalities have been described in this article are multiple evanescent white dot syndrome, acute posterior multifocal placoid pigment epitheliopathy, acute zonal occult outer retinopathy, multifocal choroiditis and panuveitis, punctate inner choroidopathy, serpiginous choroiditis, and birdshot chorioretinopathy. The various imaging modalities help us to better understand the pathophysiology of the various entities and help in diagnosing, monitoring, and prognosticating them. Optical coherence tomography angiography (OCTA) is a comparatively newer tool that helps us to visualize lesions in the choroid that correlate with indocyanine green angiography (ICGA) findings. Even though it is of limited value and cannot replace ICGA, it had gained considerable interest among ophthalmologists. Similarly, the noninvasive nature of modalities such as fundus autofluorescence and OCT makes them appealing and preferable over invasive techniques such as fundus fluorescein angiography and ICGA.

Active Ocular Toxoplasmosis Associated with Simultaneous Multiple Evanescent White Dot Syndrome

PURPOSE

We describe the association between active ocular toxoplasmosis and Multiple Evanescent White Dot Syndrome (MEWDS).

PATIENTS AND METHODS

Retrospective observational case report of a patient who presented with concomitant ocular toxoplasmosis and MEWDS (Erasmus University Hospital, Brussels, Belgium). Clinical record and multimodal imaging including fundus autofluorescence (FAF), fluorescein angiography (FA), indocyanine green angiography (ICGA), and spectral domain optical coherence tomography (SD-OCT) were analyzed.

RESULTS

Multimodal imaging of a 25-year-old-woman that presented with concomitant active ocular toxoplasmosis and MEWDS is described. Both clinical entities regressed completely after 8 weeks under steroidal anti-inflammatory drugs and antibiotics.

CONCLUSION

Active ocular toxoplasmosis can be associated with simultaneous multiple evanescent white dot syndrome. Further reports are needed to precise and characterize this clinical relationship and its management.Abbreviations: MEWDS: Multiple Evanescent White Dot Syndrome; Fundus Autofluorescence FAF; BCVA: Best-corrected Visual Acuity; FA: Fluorescein Angiography; ICGA: Indocyanine Green Angiography; SD-OCT: Spectral Domain Optical Coherence Tomography; IR: Infrared.

Choroidal hypertransmission width on optical coherence tomography: a prognostic biomarker in idiopathic macular hole surgery

PURPOSE

To test the hypothesis that optical coherence tomography (OCT) choroidal hypertransmission width (CHW) is a prognostic biomarker in idiopathic macular hole (MH) surgery METHODS: Retrospective cohort study of consecutive patients undergoing successful pars plana vitrectomy for idiopathic MH. We collected demographic, clinical, and OCT variables at the preoperative and last available visits. Two investigators assessed the following OCT parameters: MH minimum diameter, base diameter, CHW, ellipsoid zone, and external limiting membrane status (absent vs. present). Delta CHW was calculated as the difference between CHW and MH minimum diameter. Linear models were used to investigate factors associated with postoperative best-corrected visual acuity (BCVA) and BCVA change.

RESULTS

Thirty-six eyes (36 patients) with a median (interquartile range (IQR)) follow-up of 9 (8-11) months were included. The median BCVA (IQR) improved from 0.75 (1-0.6) logMAR preoperatively to 0.2 (0.6-0.1) logMAR at the last visit (p < 0.001). Preoperative MH minimum diameter (for a 10-μm increase, estimate (standard error (SE)): 0.009 (0.003) logMAR, p = 0.003), base diameter (for a 10-μm increase, 0.003 (0.001) logMAR, p = 0.032), CHW (for a 10-μm increase, 0.008 (0.002) logMAR, p < 0.001), and delta CHW (for a 10-μm increase, 0.013 (0.005) logMAR, p = 0.009) were significantly associated with postoperative BCVA. The proportion of variance explained was the highest for MH CHW (R2 0.35), followed by minimum MH diameter (R2 0.24), delta CHW (R2 0.19), and MH base diameter (R2 0.14). None of the study variables was associated with delta BCVA.

CONCLUSION

Preoperative CHW is associated with postoperative visual acuity in patients undergoing successful idiopathic MH surgery and may be a useful OCT prognostic biomarker.

Atypical multiple evanescent white dot syndrome presenting with peripheral retinal lesions

Multiple evanescent white dot syndrome (MEWDS) is a rare inflammatory eye condition. We report an atypical case of MEWDS in a man in his 30s who presented with blurred vision (visual acuity 6/9), floaters and photopsia in his left eye. Funduscopy examination showed mild peripheral nasal vascular sheathing with subtle grey-white dots highlighted on fundus autofluorescence. As far as the authors are aware, this is the first case presentation whereby areas affected by MEWDS started in the peripheral retina and migrated centrally. Fluorescein angiography showed hyperfluorescent areas in wreath-like patterns nasally. Optical coherence tomography showed disruption of the ellipsoid zone and hyperreflective projections into the outer nuclear layer. The size of the involved area increased over 3 weeks and subsequently resolved over 4 months. Simultaneously, the patient's symptoms also resolved, without treatment. This case highlights the importance of multimodal imaging, especially ultrawidefield imaging in diagnosing MEWDS.

Value and Significance of Hypofluorescent Lesions Seen on Late-Phase Indocyanine Green Angiography

Background and Purpose

The hypofluorescence of fundus lesions observed during the late phase of indocyanine green angiography (ICGA) in various diseases has often been overlooked or misinterpreted. This article explores the significance of fundus lesions that are initially isofluorescent during the early phase of ICGA but become hypofluorescent later in the examination.

Findings

Pathologies such as multiple evanescent white spot syndrome, acute posterior placoid syphilitic chorioretinitis, chronic central serous chorioretinopathy, choroidal hemangioma, and some fundus with drusen, present this phenomenon of late hypofluorescence.

Interpretation

The interpretation of ICGA images and the role of indocyanine green (ICG) uptake by the retinal pigment epithelium (RPE) in late fundus fluorescence is debated. Experimental evidence suggests that ICG accumulates progressively in the RPE after intravenous injection of the dye or after direct contact in vitro, making it a potential marker of RPE activity. Although the exact mechanisms of ICG diffusion through the choroid and its binding to the RPE require further investigation, the late hypofluorescence observed in certain ICGA diseases provides information on different modalities of RPE dysfunction.

Financial Disclosures

The author has no proprietary or commercial interest in any materials discussed in this article.

Latest advances in white spot syndromes: New findings and interpretations

White spot syndromes (WSS) pose challenges in the field of ophthalmology, particularly in terms of accurate diagnosis and effective management. However, recent advancements in multimodal imaging (MMI) have significantly contributed to our understanding of WSS, allowing for improved characterization of these inflammatory chorioretinopathies. By employing various imaging modalities, including fundus fluorescein angiography, indocyanine green angiography, fundus autofluorescence, optical coherence tomography (OCT), ultra-widefield imaging, and OCT angiography, researchers and clinicians have gained valuable insights into the underlying pathophysiological changes and clinical progression of WSS. Furthermore, MMI has unveiled novel and atypical variants within the spectrum of WSS, expanding our knowledge in this field. Notably, the identification of secondary forms of WSS occurring concurrently with unrelated chorioretinal disorders has suggested a potential autoimmune mechanism underlying these conditions. The introduction of MMI has also facilitated a more comprehensive evaluation of previously ill-defined entities, such as acute zonal occult outer retinopathy, leading to improved diagnostic criteria and enhanced recognition of distinct features. This review paper provides a comprehensive overview of the latest advances and interpretations in WSS. By integrating MMI into the diagnosis and management of these conditions, this review aims to enhance patient outcomes and provide valuable insights into the complexities surrounding WSS.

A Long Term Recurrent Case of Acute Retinal Pigment Epithelitis

PURPOSE

To describe the case of a young adult who developed two episodes of Acute Retinal Pigment Epithelitis (ARPE) in the same eye 7 years apart, describing retinal morphologic changes using SD-OCT scan.

OBSERVATIONS

ARPE is an acute, self-limiting macular disorder characterized by a stippled dark macular lesion surrounded by a hypopigmented halo under fundus examination, corresponding to a foveal disruption of the outer retinal layers and an hyperreflective lesion under SD-OCT scan. Despite ARPE lesions usually appearing to be situated within the macula, a diffuse involvement of the RPE has been suggested1. SD-OCT scan in our patient showed multiple focal lesions involving the whole posterior pole of the affected eye.

CONCLUSIONS AND IMPORTANCE

We report the first case where a diffuse involvement of the RPE in the disease is supported by an OCT finding and the case with the longest period between two recurrent self-limited episodes described so far.

Acute-Onset Retinal Conditions Mimicking Acute Optic Neuritis: Overview and Differential Diagnosis

Acute optic neuritis (AON) is a common cause of sudden visual loss in young patients. Because of the risk of demyelinating disease, patients affected by unilateral or bilateral optic neuritis should be evaluated and treated accordingly. Despite advancements in imaging of the brain and retina, misdiagnosis of AON is not uncommon. Indeed, some acute disorders of the retina have the potential to mimic AON and their prompt diagnosis may avoid unnecessary neurologic investigation, psychological stress to the patient, and delays in treatment. This review describes uncommon retinal disorders presenting with sudden-onset visual loss and absent or subtle funduscopic manifestation that can mimic AON. Multimodal retinal imaging is essential in detecting these conditions and in their differential diagnosis. It behooves neurologists and general ophthalmologists to be aware of these entities and be familiar with multimodal imaging of the retina.

Topographic patterns of retinal lesions in multiple evanescent white dot syndrome

PURPOSE

To demonstrate different topographic distributions of multiple-evanescent white dot syndrome (MEWDS) and secondary MEWDS disease and to describe possible associations.

METHODS

Clinical evaluation and multimodal retinal imaging in 27 subjects with MEWDS (29 discrete episodes of MEWDS). Ophthalmic assessment included best-corrected visual acuity testing and multimodal retinal imaging with OCT, blue-light autofluorescence, fluorescein and indocyanine green angiography, fundus photography, and widefield pseudocolor and autofluorescence fundus imaging.

RESULTS

The topographic distribution of MEWDS lesions was centered on or around the optic disc (n = 17, 59%), centered on the macula (n = 7, 24%), sectoral (n = 2, 7%), or was indeterminate (n = 3, 10%). The MEWDS episodes either occurred in the absence ('primary MEWDS'; n = 14, 48%) or presence of concurrent chorioretinal pathology ('secondary MEWDS'; n = 15, 52%). In patients with the latter, MEWDS lesions were often centered around a coexisting chorioretinal lesion. The majority of patients in both groups experienced resolution of their symptoms and retinal changes on multimodal imaging by 3 months.

CONCLUSIONS

Distinct distributions of MEWDS lesions were identified. MEWDS may occur in tandem with other chorioretinal pathology, which may impact the topography of MEWDS lesions.

Blue-Light Fundus Autofluorescence (BAF), an Essential Modality for the Evaluation of Inflammatory Diseases of the Photoreceptors: An Imaging Narrative

Our purpose is to describe blue-light fundus autofluorescence (BAF) features of inflammatory diseases of the outer retina characterised by photoreceptor damage. BAF from patients diagnosed with secondary and primary inflammatory photoreceptor damage were retrospectively analyzed and compared to other imaging modalities including fluorescein angiography (FA), indocyanine green angiography (ICGA), and spectral domain optical coherence tomography (SD-OCT). Multiple evanescent white dot syndrome (MEWDS), idiopathic multifocal choroiditis (MFC), acute posterior multifocal placoid pigment epitheliopathy (APMPPE), serpiginous choroiditis (SC), and acute syphilitic posterior placoid chorioretinitis (ASPPC), all cases corresponding to secondary photoreceptor diseases caused by inflammatory choriocapillaris nonperfusion, were included and compared to primary photoreceptor disease entities, including acute zonal occult outer retinopathy (AZOOR) and cancer-associated retinopathy (CAR). Both groups showed increased BAFs of variable intensity. In severe cases of APMPPE and ASPPC, BAF also showed hypoautofluorescent areas. In group 1 (secondary diseases) BAF hyperautofluorescent areas were associated with colocalized ICGA hypofluorescent areas, indicating choriocapillaris nonperfusion; whereas in group 2 (primary diseases), no ICGA signs were detected. The associated colocalized areas of hypofluorescence on ICGA in the first group, which were absent in the second group, were crucial to allow the differentiation between primary (photoreceptoritis) and secondary (choriocapillaritis) photoreceptor diseases. BAF patterns in inflammatory diseases of the outer retina can give relevant information on the photoreceptor and RPE involvement, with ICGA being crucial to detect concurring choriocapillaris damage and differentiating the two pathologies.

Early recognition of CLN3 disease facilitated by visual electrophysiology and multimodal imaging

BACKGROUND

Neuronal ceroid lipofuscinosis is a group of neurodegenerative disorders with varying visual dysfunction. CLN3 is a subtype which commonly presents with visual decline. Visual symptomatology can be indistinct making early diagnosis difficult. This study reports ocular biomarkers of CLN3 patients to assist clinicians in early diagnosis, disease monitoring, and future therapy.

METHODS

Retrospective review of 5 confirmed CLN3 patients in our eye clinic. Best corrected visual acuity (BCVA), electroretinogram (ERG), ultra-widefield (UWF) fundus photography and fundus autofluorescence (FAF), and optical coherence tomography (OCT) studies were undertaken.

RESULTS

Five unrelated children, 4 females and 1 male, with median age of 6.2 years (4.6-11.7) at first assessment were investigated at the clinic from 2016 to 2021. Four homozygous and one heterozygous pathogenic CLN3 variants were found. Best corrected visual acuities (BCVAs) ranged from 0.18 to 0.88 logMAR at first presentation. Electronegative ERGs were identified in all patients. Bull's eye maculopathies found in all patients. Hyper-autofluorescence ring surrounding hypo-autofluorescence fovea on FAF was found. Foveal ellipsoid zone (EZ) disruptions were found in all patients with additional inner and outer retinal microcystic changes in one patient. Neurological problems noted included autism, anxiety, motor dyspraxia, behavioural issue, and psychomotor regression.

CONCLUSIONS

CLN3 patients presented at median age 6.2 years with visual decline. Early onset maculopathy with an electronegative ERG and variable cognitive and motor decline should prompt further investigations including neuropaediatric evaluation and genetic assessment for CLN3 disease. The structural parameters such as EZ and FAF will facilitate ocular monitoring.

Multiple Evanescent White Dot Syndrome Associated with Coronavirus Infection: A Case Report

Coronavirus disease 2019 (COVID-19) causes ocular manifestations in approximately 11% of patients. Most patients typically develop ocular symptoms within 30 days of the onset of the first COVID-19 symptoms. The most common ocular manifestation is conjunctivitis, which affects nearly 89% of patients with eye problems. Other much less common anterior segment abnormalities caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) are scleritis, episcleritis, and acute anterior uveitis. Posterior segment abnormalities caused by SARS-CoV-2 are mainly vascular, such as hemorrhages, cotton wool spots, dilated veins, and vasculitis. Herein, we report a rare manifestation of COVID-19 and multiple evanescent white dot syndrome (MEWDS) of the retina. In April 2021, a 40-year-old female patient was admitted to the Eye Clinic of Clinical Center of Montenegro (Podgorica, Montenegro). The patient's main complaint was sudden vision impairment, which occurred 14 days after a positive polymerase chain reaction (PCR) test result for SARS-CoV-2 infection. A complete eye examination was performed, followed by fundoscopy, optical coherence tomography (OCT), and fluorescein angiography (FA) tests. The results showed retinal changes associated with MEWDS. The patient underwent additional examinations to rule out common causes of multifocal retinitis, all of which were unremarkable. Therefore, it was concluded that retinitis was a complication of COVID-19. Given its non-invasive nature, fundus examination should be used as a standard screening method for retinal changes in patients with COVID-19.

The role of near-infrared reflectance imaging in retinal disease: A systematic review

Near-infrared reflectance (NIR) retinal imaging aids in a better visualization of structures at the level of outer retina, retinal pigment epithelium, and choroid. It has multiple advantages, including easy acquisition in association with structural spectral domain optical coherence tomography, more comfort for patients, and enhanced contrast and spatial resolution. It helps in the diagnosis of chorioretinal diseases that present with minimal funduscopic findings and can be used to follow up many chorioretinal conditions. We describe the chorioretinal NIR imaging appearance and the clinical role of NIR imaging in ocular inflammatory disease, vascular and acquired disease, degenerative disease, tumors, associated systemic condition, toxic and traumatic disease, optic nerve head conditions, and physiological findings.

Imaging-based Assessment of Choriocapillaris: A Comprehensive Review

PURPOSE

Over the past two decades, advancements in imaging modalities have significantly evolved the diagnosis and management of retinal diseases. Through these novel platforms, we have developed a deeper understanding of the anatomy of the choroidal vasculature and the choriocapillaris. The recently developed tools such as optical coherence tomography (OCT) and OCT angiography (OCTA) have helped elucidate the pathological mechanisms of several posterior segment diseases. In this review, we have explained the anatomy of the choriocapillaris and its close relationship to the outer retina and retinal pigment epithelium.

METHODS

A comprehensive search of medical literature was performed through the Medline/PubMed database using search terms: choriocapillaris, choroid, quantification, biomarkers, diabetic retinopathy, age-related macular degeneration, choroidal blood flow, mean blur rate, flow deficit, optical coherence tomography, optical coherence tomography angiography, fluorescein angiography, indocyanine green angiography, OCTA, Doppler imaging, uveitis, choroiditis, white dot syndrome, tubercular serpiginous-like choroiditis, choroidal granuloma, pachychoroid, toxoplasmosis, central serous chorioretinopathy, multifocal choroiditis, choroidal neovascularization, choroidal thickness, choroidal vascularity index, choroidal vascular density, and choroidal blood supply. The search terms were used either independently or combined with choriocapillaris/choroid.

RESULTS

The imaging techniques which are used to qualitatively and quantitatively analyze choriocapillaris are described. The pathological alterations in the choriocapillaris in an array of conditions such as diabetes mellitus, age-related macular degeneration, pachychoroid spectrum of diseases, and inflammatory disorders have been comprehensively reviewed. The future directions in the study of choriocapillaris have also been discussed.

CONCLUSION

The development of imaging tools such as OCT and OCTA has dramatically improved the assessment of choriocapillaris in health and disease. The choriocapillaris can be delineated from the stromal choroid using the OCT and quantified by manual or automated methods. However, these techniques have inherent limitations due to the lack of an anatomical distinction between the choriocapillaris and the stromal choroid, which can be overcome with the use of predefined segmentation slabs on OCT and OCTA. These segmentation slabs help in standardizing the choriocapillaris imaging and obtain repeatable measurements in various conditions such as diabetic retinopathy, age-related macular degeneration, pachychoroid spectrum, and ocular inflammations. Additionally, Doppler imaging has also been effectively used to evaluate the choroidal blood flow and quantifying the choriocapillaris and establishing its role in the pathogenesis of various retinochoroidal diseases. As tremendous technological advancements such as wide-field and ultra-wide field imaging take place, there will be a significant improvement in the ease and accuracy of quantifying the choriocapillaris.

Nahinfrarot-Autofluoreszenz: klinische Anwendung und diagnostische Relevanz

Die Nahinfrarot-Autofluoreszenz (NIA) ist ein nicht-invasives Verfahren zur Untersuchung des retinalen Pigmentepithels (RPE) basierend auf der Darstellung des antioxidativen Schutzfaktors Melanin in den RPE-Zellen. Die NIA verbessert die Früherkennung chorioretinaler Erkrankungen, da bei vielen dieser Erkrankungen mit der NIA Strukturveränderungen des RPE nachweisbar sind, bevor sich in anderen Untersuchungen Krankheitszeichen erkennen lassen.

[Near-infrared Fundus Autofluorescence: Clinical Application and Diagnostic Relevance]

Near-infrared autofluorescence (NIA) is a non-invasive retinal imaging technique for examination of the retinal pigment epithelium (RPE) based on the autofluorescence of melanin. Melanin has several functions within the RPE cells, in one of them it serves as a protective antioxidative factor within the RPE cells and is involved in the phagocytosis of photoreceptor outer segments. Disorders that affect the photoreceptor-RPE complex result in alterations of RPE cells which are detectable by alterations of NIA. Therefore, NIA allows to detect early alterations in inherited and acquired chorioretinal disorders, frequently prior to ophthalmoscopical visualisation and often prior to alterations in lipofuscin associated fundus autofluorescence (FAF) or optical coherence tomography (OCT). Although NIA and FAF relate to disorders affecting the RPE, findings between both imaging methods differ and the area involved has been demonstrated to be larger in NIA compared to FAF in several disorders (e.g., age-related macular degeneration, retinitis pigmentosa, ABCA4-gene associated Stargardt disease and cone-rod dystrophy, light damage), indicating that NIA detects earlier alterations compared to FAF. In addition, due to the absence of blue-light filtering which limits foveal visualisation in FAF, foveal alterations can be much better detected using NIA. A reduced subfoveal NIA intensity is the earliest sign of autosomal dominant BEST1-associated disease, when FAF and OCT are still normal. In other disorders, a normal subfoveal NIA intensity is associated with good visual acuity. This review summarizes the present knowledge on NIA and demonstrates biomarkers for various chorioretinal disorders.

The Role of Optical Coherence Tomography and Optical Coherence Tomography Angiography in the Differential Diagnosis of Posterior Uveitis

PURPOSE

Modalities such as optical coherence tomography (OCT) and OCT angiography (OCTA) have improved the diagnostic utility of fundus imaging in management of uveitis. The purpose of this study is to review role of OCT and OCTA in differential diagnosis of certain posterior uveitic entities.

METHODS

Narrative review.

RESULTS

In this review, we have comprehensively summarized the utility of OCT and OCTA in helping the clinician diagnose common but challenging inflammatory conditions including ocular toxoplasmosis, viral retinitis, and vitreoretinal lymphoma, among others. OCT and OCTA can also be used to assess the choriocapillaris involvement in conditions such as multiple evanescent white dot syndrome, and choroidal granulomas in tubercular and sarcoid uveitis.

CONCLUSIONS

Fundus imaging with OCT and OCTA has assumed a significant role in establishing the diagnosis in uveitis apart from microbiological and other laboratory analysis. Advantages such as rapidity and non-invasiveness make these imaging modalities very useful and convenient.

Coarsening of choriocapillaris on optical coherence tomography angiography as a sign of acute idiopathic blind spot enlargement

Purpose

Acute idiopathic blind spot enlargement is a rare syndrome that is classified within a spectrum of primary inflammatory choriocapillaropathies with circumscribed outer retinal dysfunction.

Observations

We observed coarsening of the choriocapillaris on en-face optical coherence tomography angiography when compared to the fellow eye in a patient with suspected acute idiopathic blind spot enlargement.

Conclusions and Importance

Increased granularity of the choriocapillaris as imaged by optical coherence tomography angiography may assist in the diagnosis of acute idiopathic blind spot enlargement, particularly during a global pandemic when access to electrodiagnostics is limited. This finding supports the current evidence of choriocapillaris hypoperfusion in the pathogenesis of acute idiopathic blind spot enlargement.

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Acute idiopathic blind spot enlargement is a rare syndrome.

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It is classified within a spectrum of primary inflammatory choriocapillaropathies.

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Optical coherence tomography angiography is useful in diagnosing acute idiopathic blind spot enlargement.

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Coarsening of the choriocapillaris as imaged by optical coherence tomography angiography is seen in this disease.

Measuring Inflammation in the Vitreous and Retina: A Narrative Review

Uveitis consists of a group of syndromes characterised by intraocular inflammation, accounting for up to 15% of visual loss in the western world and 10% worldwide. Assessment of intraocular inflammation has been limited to clinician-dependent, subjective grading. Developments in imaging technology, such as optical coherence tomography (OCT), have enabled the development of objective, quantitative measures of inflammatory activity. Important quantitative metrics including central macular thickness and vitreous signal intensity allow longitudinal monitoring of disease activity and can be used in conjunction with other imaging modalities enabling holistic assessment of ocular inflammation. Ongoing work into the validation of instrument-based measures alongside development of core outcome sets is crucial for standardisation of clinical trial endpoints and developing guidance for quantitative multi-modal imaging approaches. This review outlines methods of grading inflammation in the vitreous and retina, with a focus on the use of OCT as an objective measure of disease activity.

Navigating the White Dot Syndromes with Optical Coherence Tomography (OCT) and OCT Angiography (OCT-A)

INTRODUCTION

White dot syndromes are a heterogeneous group of diseases that affect different layers in the retina and choroid. Multimodal imaging is fundamental in the diagnosis, but also can be crucial in unveiling the pathogenesis of these entities.

MATERIAL AND METHODS

Literature review.

RESULTS

Optical coherence tomography (OCT) provides depth-resolved, histological grade images of the vitreous, retina, and choroid. This technology is very useful to localize the primary nature and level of pathology of the various white dot syndromes. En face OCT can provide additional information regarding the interrelationship of lesion types. Vascular involvement at the level of the retina, choriocapillaris or choroid can be assessed by en face OCT angiography (OCT-A) and is not limited by masking, leakage or staining as can occur with conventional angiography (fluorescein or indocyanine green angiography) which requires dye injection.

CONCLUSION

OCT and OCTA are fundamental in the diagnosis and follow-up of white dots syndromes.

Indocyanine Green Angiography Features in Acute Syphilitic Posterior Placoid Chorioretinitis

PURPOSE

Acute syphilitic posterior placoid chorioretinitis (ASPPC) is a rare clinical manifestation of ocular syphilis. The cause of the placoid lesion is still up for debate but could be caused by an impaired choriocapillaris perfusion. However, less attention has been paid to the hypofluorescence of the plaque on late-phase indocyanine green angiography (ICGA). The aim of this study was to comprehensively analyze multimodal imaging findings in patients with ASPPC and to highlight the value of ICGA for the diagnosis of ASPPC.

DESIGN

Retrospective observational case study.

METHODS

The medical records of patients with uveitis who consulted our tertiary center between 2012 and December 2015 were reviewed. Patients who were diagnosed with uveitis related to syphilis infection with posterior placoid lesions seen on multimodal imaging were included. We compared the aspect of ASPPC on fundus color photography, blue autofluorescence, fluorescein angiography, optical coherence tomography, and early-, mid- and late-phase ICGA.

RESULTS

Fifteen eyes of 12 patients were included in the study. Hypofluorescent plaques were seen on late-phase ICGA in all eyes, corresponding to the placoid lesions visible on blue autofluorescence, while the choriocapillaris filling was normal on fluorescein angiography and ICGA. Within the plaques, optical coherence tomography showed ellipsoid zone disruptions, outer retinal disruptions, and retinal pigment epithelium granulations.

CONCLUSION

ASPPC could be caused by retinal pigment epithelium dysfunction secondary to an infectious or inflammatory disorder, characterized by a hypofluorescence visible only on late-phase ICGA, and resulting in photoreceptor disruptions. The RPE impairment was reversible after prompt antibiotic treatment.

Choroidal Imaging in uveitis: an update

An important goal of advancements in ocular imaging algorithms and devices has been to improve the image acquisition and resolution of deeper ocular tissues, namely the choroid and its vasculature that are otherwise inaccessible to direct clinical examination. These advancements have contributed to the understanding of the pathophysiology of a number of ocular inflammatory conditions. We focuse on the imaging characteristics of clinical conditions where imaging the choroid has improved or radically changed the understanding of the disease, has helped in differentiation of phenotypically similar but distinct lesions, and where imaging features have proven vital formonitoring disease activity. The last two decades have seen some major developments in ocular imaging relevant to uveitis. The current review addresses both the imaging characteristics and their interpretation on conventional modalities such as fundus photography, fluorescein angiography, indocyanine green angiography and fundus autofluorescence and the recent additions in the armamentarium including optical coherence tomography (OCT) with enhanced depth imaging, swept-source OCT, and OCT angiography.

Multimodal imaging in multiple evanescent white dot syndrome and new insights in pathogenesis

PURPOSE

To report the multimodal imaging in multiple evanescent white dot syndrome (MEWDS) during the acute and convalescent stages in order to better understand the focus of the inflammatory process.

METHODS

Retrospective cohort study of 4 patients with MEWDS. Each patient underwent: enhanced depth imaging-optical coherence tomography (EDI-OCT), fundus autofluorescence (FAF), fluorescein angiography (FA), indocyanine green angiography (ICGA) and en-face OCT and OCT angiography (OCT-A). Choroidal subfoveal thickness (CST) was measured manually. All patients were studied in the acute stage and convalescent stage after disappearance of OCT abnormalities and resolution of visual symptoms.

RESULTS

Four MEWDS patients with a mean age of 23.5years were studied (range: 16-33years). Two patients were women. Initial mean visual acuity (VA) was 80.25 ETDRS. Final mean VA was 84.25 ETDRS. OCT imaging showed disruption of the ellipsoid zone and a slightly elevated RPE layer with overlying hyperreflective material, all of which corresponded to hyperautofluorescent FAF lesions. FA revealed multiple hyperautofluorescent lesions, correlated with hypocyanescent spots on the late ICGA. OCT-A showed normal superficial and deep retinal capillary plexus as well as choriocapillaris. The disease was self-limited in all the cases, with a mean time of 9weeks to resolution (range: 4-16).

CONCLUSION

The pathophysiology of MEWDS is still debated. We believe that there is still not enough evidence to implicate the outer retina as the primary cause. For now, we suggest that this transient disease is the consequence of choriocapillaris hypoperfusion, but further studies are required to elucidate this hypothesis.

Multimodal imaging supporting the pathophysiology of white dot syndromes

White dot syndromes (WDS) represent a heterogeneous group of inflammatory diseases, primarily affecting the outer retina, choriocapillaris and choroid. Recent advances in the field of ocular imaging and development of new technologies, including optical coherence tomography angiography (OCT-A), have allowed a better characterization of the morphology of these conditions. This review will analyse the WDS from an imaging-based perspective, providing a better understanding of the pathophysiology underlying these disorders.

Multiple evanescent white dot syndrome: clinical course and factors influencing visual acuity recovery

Objective

To report the demographics and the clinical course of patients with multiple evanescent white dot syndrome (MEWDS) and to investigate for those factors which influence visual acuity (VA) recovery.

Methods

This is a retrospective single-centre observational study. Electronic medical records and retinal imaging of patients with a diagnosis of MEWDS with a minimum follow-up of 3 months were reviewed. Patients were categorised into three groups according to the VA at presentation and at the last visit: group 1 >0.48 logarithm of the minimum angle of resolution (LogMAR), group 2 ≤0.48 and ≥0.18 LogMAR and group 3 <0.18 LogMAR. All patients had non-invasive multimodal imaging including optical coherence tomography, near-infrared reflectance imaging and blue fundus autofluorescence at presentation and during follow-up.

Results

A total of 51 eyes from 51 patients (41 women, mean age 29.8±7.8 years) were included. Significantly more patients presented in the autumn (X2=8.69, p=0.034). The percentage of eyes recovering vision to 0.0 LogMAR or better was 80.3% (41/51). Worse presenting vision and young age at presentation were independent significant predictive variables for poorer final VA (p=0.002 and p=0.02, respectively). No imaging features were significantly predictive of complete versus incomplete recovery, but disc hyperfluorescence on fluorescein angiography was more common in those with incomplete recovery.

Conclusions

Although the majority of cases have a benign prognosis, the clinical spectrum of MEWDS includes incomplete visual recovery. In our series, poor presenting VA and young age were associated with poor VA outcome. Further study is warranted to confirm these findings.

Choroidal nonperfusion on optical coherence tomography angiography in a case of unilateral posterior segment ocular sarcoidosis misdiagnosed as MEWDS

PURPOSE

To report a case of presumed ocular sarcoidosis initially presenting with features of multiple evanescent white dot syndrome (MEWDS) with atypical optical coherence tomography angiography (OCTA) findings.

OBSERVATIONS

A 23 year-old woman presented with a unilateral central scotoma, photophobia, and decreased visual acuity after a viral illness. Examination of the right eye revealed multiple round white macular spots and stippled granularity at the fovea. Multimodal imaging with fluorescein angiography (FA), indocyanine green angiography (ICG), fundus autofluorescence (FAF), and optical coherence tomography (OCT) was consistent with a diagnosis of MEWDS. However, OCTA demonstrated choriocapillaris (CC) flow deficits, which is not typical for MEWDS. The clinical course was initially consistent with MEWDS, with spontaneous recovery of symptoms over ensuing months. The patient presented five months later with floaters and a central scotoma. Examination showed panuveitis, and systemic evaluation revealed an elevated angiotensin converting enzyme (ACE) and hilar lymphadenopathy on chest x-ray consistent with presumed sarcoidosis.

CONCLUSIONS AND IMPORTANCE

A case of MEWDS atypically demonstrated CC flow deficits on OCTA and subsequently presented as uveitis secondary to presumed sarcoidosis. Atypical features in MEWDS may be a sign of another disorder masquerading early on as MEWDS and ought to prompt further investigation.

Ophthalmic and Neuro-ophthalmic Manifestations of Coronavirus Disease 2019 (COVID-19)

PURPOSE

To describe a case of inflammatory chorioretinopathy and Adie's syndrome possibly associated with COVID-19.

METHODS

Observational case report.

RESULTS

A 51-year-old woman developed fever, cough, and headache followed by retro-ocular pain and reading impairment. She tested positive for SARS-COV-2 infection by qualitative real-time reverse-transcriptase-polymerase-chain-reaction. The slit-lamp and funduscopic exam revealed abnormal pupillary response and yellowish creamy deep chorioretinal lesions, which were not present in previous examinations. Instillation of pilocarpine demonstrated denervation supersensitivity, and it was suggestive of bilateral Adie tonic pupil. A comprehensive work-up ruled out other systemic, autoimmune, or infectious diseases.

CONCLUSIONS

This case illustrates the possible association between multifocal chorioretinitis and Adie's syndrome, and the SARS-COV-2 infection in humans. Further investigation of virus infectivity specifically within ocular tissues has to be conducted.

Advances in imaging of uveitis

Advances in multimodal imaging have significantly contributed to the management of many uveitis diseases in recent years. The most significant developments include the use of optical coherence tomography to obtain a more accurate and reproducible assessment of ocular inflammation, the application of optical coherence tomography angiography in choroiditis and retinal vasculitis, new possibilities for studying vitritis with ultrawide field imaging, and the most recent applications of fundus autofluorescence in uveitis. In this review, we provide an overview of the most significant advances in multimodal imaging of uveitis achieved in recent years.

Quantitative analysis of retinal and choriocapillary vascular density of multiple evanescent white dot syndrome by optical coherence tomography angiography

PURPOSE

To describe optical coherence tomography angiography (OCTA) and other multimodal imaging features of multiple evanescent white dot syndrome (MEWDS).

METHODS

The retinal and choriocapillary vascular density of MEWDS patients were measured by OCTA (OptoVue Inc.) in the acute and recovery phases. And other multimodal imaging data were also retrospectively reviewed.

RESULTS

Sixteen patients with a mean age of 26.5 ± 6.99 years were included. Three patients were complicated with choroidal neovascularization (CNV). The mean baseline logMAR BCVA of the affected eyes was 0.52 ± 0.36 (Snellen equivalent 20/50). OCTA revealed significant reductions in vascular densities of deep capillary plexus (45.72 ± 3.70%, P = 0.0007), and choriocapillaris (46.08 ± 3.22%, P < 0.0001) of the affected eyes compared with the contralateral eyes (50.23 ± 4.06% and 52.28 ± 4.19%, respectively) in the acute phase. During the recovery phases, vascular densities of deep capillary plexus (49.50 ± 3.15%, P < 0.0001) and choriocapillaris (53.67 ± 2.58%, P < 0.0001) increased significantly in the affected eyes while those of the superficial capillary plexus remained stable. SD-OCT revealed an increase of the subfoveal choroidal thickness and disruption of the outer retinal layer, including ellipsoid zone discontinuities and the accumulation of hyperreflective material, corresponding to the hypofluorescent spots and dots on ICGA, respectively. BCVA increased to normal values after recovery, together with restoration of the structural morphology and choroidal thickness on SD-OCT, except in eyes with CNV.

CONCLUSION

The inner retinal layer and choroid can be secondarily transiently compromised in MEWDS. MEWDS complicated with CNV is associated with worse visual outcomes.

Spectralis High Magnification Module imaging in a case of Multiple Evanescent White Dot Syndrome

Purpose

To report the use of Spectralis High Magnification Module (HMM) as part of multimodal imaging in Multiple Evanescent White Dot Syndrome (MEWDS).

Observations

HMM imaging showed a blurry mosaic pattern corresponding to MEWDS-related photoreceptors’ lesions. These abnormalities remained detectable at later stages of the disease while other imaging modalities were negative.

Conclusions and importance

HMM can be a useful technique to monitor the structure of the outer retina during the different stages of MEWDS.

Choroidal Vascular Changes in Multiple Evanescent White Dot Syndrome

Purpose: To evaluate choroidal structural changes in patients with multiple evanescent white dot syndrome (MEWDS) during the acute and recovery stages.Methods: Enhanced-depth imaging optical coherence tomography (EDI-OCT) scans of 16 patients with unilateral MEWDS were acquired during the acute and recovery stages in both eyes. Images were binarized with the ImageJ software to measure subfoveal choroidal thickness (CT), total choroid area, luminal area and choroidal vascularity index (CVI).Results: In the acute stage, subfoveal CT, total choroidal area and CVI were significantly higher in eyes with MEWDS compared to fellow eyes (371.2 ± 101.8 vs 317.1 ± 90.3 µm, p = .001; 2.826 ± 0.686 vs 2.524 ± 0.674 mm², p = .014; 69.49 ± 3.51 vs 68.27 ± 3.41%, p = .044, respectively). In the recovery stage, subfoveal CT, total choroidal area and CVI in eyes with MEWDS significantly decreased to respectively 333.4 ± 90.5 µm, p = .007, 2.592 ± 0.570 p = .002, and 67.31 ± 2.74%, p = .014.Conclusions: Choroidal thickness and vascularity are significantly increased during the acute stage of MEWDS.