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

Spatial Distribution of Hyperreflective Choroidal Foci in the Macula of Normal Eyes

Purpose

To investigate variations in the spatial distribution of hyperreflective foci in the choroid of the macula in normal eyes.

Methods

We included eyes with a normal fundus from patients who had undergone optical coherence tomography angiography, covering a 6-mm × 6-mm area centered on the fovea. The macular area was divided into nine sectors according to the modified Early Treatment of Diabetic Retinopathy Study grid. Hyperreflective choroidal foci (HCF) distribution, choriocapillaris vascular density, and choroidal stromal density were determined on en face images of the choroid in each sector.

Results

We included 35 eyes from 35 participants, with a mean age of 52.7 ± 16.8 years. The mean number and area fraction of HCF at the 5-mm macular area were 35.6 ± 7.8 foci/mm2 and 3.0% ± 0.7%, respectively. The number of HCF in the central circle (50.7 ± 20.9 foci/mm2) was greater than that in the inner (35.1 ± 13.0 foci/mm2) or outer rings (35.6 ± 6.5 foci/mm2) (P < 0.001, P < 0.001, respectively). The area fraction of HCF in the central circle (4.84% ± 3.36%) was greater than that in the inner (2.62% ± 1.17%; P < 0.001) or outer rings (3.12% ± 0.67%; P = 0.004). The HCF distribution did not significantly correlate with the choriocapillaris vascular density or choroidal stromal density in each sector.

Conclusions

HCF were more densely distributed in the macular center than in the pericentral or peripheral macular areas.

Translational Relevance

HCF measurement and spatial distribution could provide additional information for evaluating choroidal stromal characteristics.

Reversible Choriocapillaris Flow Voids in Acute Syphilitic Posterior Placoid Chorioretinitis

PURPOSE

To report two cases of acute syphilitic posterior placoid chorioretinitis (ASPPC) with choriocapillaris flow voids that partially resolved with systemic antibiotic treatment.

METHODS

Observational case report with multimodal imaging.

RESULTS

Two young healthy men suffered an acute monocular loss of vision. Spectral domain optical coherence tomography (SD-OCT) and OCT angiography (OCT-A) revealed outer retinitis with loss of the ellipsoid layer and choriocapillaris flow voids. Systemic work-up revealed syphilis. Upon systemic treatment with antibiotics, the patients recovered their vision and the OCT and OCT-A abnormalities partially resolved.

CONCLUSIONS

Transient choriocapillaris flow voids characterize ASPPC and may be responsible for the visual loss seen in these patients.

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.

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.

Multiple evanescent white dot syndrome (MEWDS): update on practical appraisal, diagnosis and clinicopathology; a review and an alternative comprehensive perspective

BACKGROUND

Multiple evanescent white dot syndrome (MEWDS) is a rare inflammatory eye condition affecting the outer retina as a consequence of choriocapillaris non perfusion. The pathophysiology of MEWDS will be discussed based clinical appraisal and on multimodal imaging appraisal.

METHODS

Narrative review and perspective opinion.

RESULTS

Literature review results helped us to put forward (1) the specific symptomatology (decreased/blurred vision, photopsia, subjective scotomas), (2) the ill-asserted character of clinical findings (foveal granularity, white dots in fundoscopy), (3) and the crucial importance of multimodal imaging with the diagnostic triad of ICGA hypofluorescent areas, BL-FAF hyperautofluorescent areas and loss/damage of IS/OS-ellipsoid zone on SD-OCT that characterise the disease and can practically help the clinician to diagnose MEWDS. A comprehensive alternative perspective of the disease was formulated.

CONCLUSIONS

The bulk of evidence that we are presenting in this review, thanks to new performing non-invasive and invasive imaging modalities, is sufficiently compelling to consider MEWDS as a primary choriocapillaritis/inflammatory choriocapillaropathy. Multimodal imaging allows the clinician to diagnose MEWDS with a high level of certainty and ensures a precise follow-up.

ACUTE SYPHILITIC POSTERIOR PLACOID CHORIORETINITIS: MULTIMODAL IMAGING AND ELECTROPHYSIOLOGIC FINDINGS BEFORE AND AFTER TREATMENT

PURPOSE

To describe the clinical course of acute syphilitic posterior placoid chorioretinitis (ASPPC) in the preplacoid stage, placoid stage, and after treatment with penicillin.

METHOD

A retrospective case report of serial multimodal imaging and electrophysiology studies of a patient with ASPPC, with 18 months of follow-up.

RESULTS

A 47-year-old man presented with bilateral panuveitis. The patient defaulted follow-up and returned when his vision deteriorated. Tests for neurosyphilis and retroviral disease were positive, and treatment was initiated. The earliest change on serial optical coherence tomography was loss of the signal from the reflective band corresponding to the ellipsoid zone. In the placoid stage, there was nodular thickening of the retinal pigment epithelium. The ellipsoid zone signals reappeared after treatment. Fundus fluorescein angiogram at presentation showed peripapillary vasculitis and disk leakage; indocyanine green angiography revealed multiple hypofluorescent spots in the peripapillary region and posterior pole that was not visible clinically. The angiographic abnormalities resolved after treatment. Electrophysiology demonstrated bilateral maculopathy and reduction of both a- and b-waves from dark-adapted and light-adapted responses at presentation. The b-waves (inner retina) recovered partially with treatment.

CONCLUSION

To the best of our knowledge, this is the first case report of the multimodal imaging and electrophysiology findings in a patient with acute syphilitic posterior placoid chorioretinitis, before the development of the classic placoid lesion. Improvement of structural and functional pathology after systemic treatment is demonstrated.

Classification Criteria For Multiple Evanescent White Dot Syndrome

PURPOSE

The purpose of this study was to determine classification criteria for multiple evanescent white dot syndrome (MEWDS).

DESIGN

Machine learning of cases with MEWDS and 8 other posterior uveitides.

METHODS

Cases of posterior uveitides were collected in an informatics-designed preliminary database, and a final database was constructed of cases achieving supermajority agreement on diagnosis using formal consensus techniques. Cases were split into a training set and a validation set. Machine learning using multinomial logistic regression was used in the training set to determine a parsimonious set of criteria that minimized the misclassification rate among the infectious posterior, or panuveitides. The resulting criteria were evaluated in the validation set.

RESULTS

A total of 1,068 cases of posterior uveitides, including 51 cases of MEWDS, were evaluated by machine learning. Key criteria for MEWDS included: 1) multifocal gray-white chorioretinal spots with foveal granularity; 2) characteristic imaging on fluorescein angiography ("wreath-like" hyperfluorescent lesions) and/or optical coherence tomography (hyper-reflective lesions extending from retinal pigment epithelium through ellipsoid zone into the retinal outer nuclear layer); and 3) absent to mild anterior chamber and vitreous inflammation. Overall accuracy for posterior uveitides was 93.9% in the training set and 98.0% (95% confidence interval: 94.3-99.3) in the validation set. Misclassification rates for MEWDS were 7% in the training set and 0% in the validation set.

CONCLUSIONS

The criteria for MEWDS had a low misclassification rate and appeared to perform sufficiently well for use in clinical and translational research.

[Application of high-resolution optical coherence tomography for visualization of eye structures in uveitis of different localization]

The article presents an analysis of publications in main Russian and foreign journals devoted to the use of optical coherence tomography in intravital visualization of the structures of the eye for diagnosis, assessment of the changes during relapses, recovery and remission stages, as well as the effectiveness of treatment for uveitis of different localization. It describes in detail the results of studies conducted using spectral optical coherence tomography, changes in the anterior chamber and cornea in uveitis of the anterior localization, morphological changes in the vitreous body, vitreomacular interface, retina, choroid and optic disc in the anterior and posterior localization of inflammation, and presents the features of OCT diagnosis in a number of nosological forms of uveitis based on the literature data.

Multiple evanescent white dot syndrome following influenza immunization - A multimodal imaging study

Purpose

To describe the multimodal imaging (MMI) findings and clinical course of a case of Multiple Evanescent White Dot Syndrome (MEWDS) following immunization with inactivated intra-dermal influenza virus, and to explore whether similarities exist with other, previously reported cases.

Observations

A 34-year-old Caucasian man presented with unilateral onset of para-central scotomata, photopsias, and dyschromatopsia two weeks after administration of an influenza vaccine. Clinical examination and MMI were indicative of MEWDS. The patient's MMI abnormalities and symptoms resolved spontaneously after four weeks.

Conclusion and importance

This is the first reported case of MMI of post-influenza vaccination-associated MEWDS. Comparison with eight previously reported cases of MEWDS following various immunizations revealed that subjects tended to be healthy, young to middle age women with a median time to onset of two weeks. Vision tended to recover spontaneously over one to three months.

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.

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.

Involvement of Inner Choroidal Layer in Choroidal Thinning during Regression of Multiple Evanescent White Dot Syndrome

Purpose

To investigate relationships between total thickness and the thickness of inner and outer layers in the choroid during regression in patients with multiple evanescent white dot syndrome (MEWDS).

Methods

This retrospective observational case series included 15 unilaterally affected eyes and 13 unaffected fellow eyes from 15 MEWDS patients (4 men and 11 women; mean age, 37.6 ± 17.6 years). Using enhanced depth imaging optical coherence tomography, whole, inner, and outer choroidal layer thicknesses at the fovea and perifovea were manually measured at the initial visit and at 1 and 3 months after the initial visit. The mean thickness values of the layers were compared at each stage.

Results

With regression of MEWDS, the mean subfoveal whole and inner choroidal layer thicknesses significantly decreased at 1 and 3 months compared to baseline values in MEWDS eyes (P=0.01 and P < 0.0001, respectively), but not in fellow eyes. The outer layer in MEWDS eyes tended to thin. Changes in the inner and outer layers at the perifovea in MEWDS eyes also showed the same trends. Simple linear regression analysis revealed significant positive correlations in choroidal thickness changes between the whole and inner layers (R = 0.53, P=0.04) and between the whole and outer layers (R = 0.91, P < 0.0001) from baseline to 3 months. Multiple linear regression analysis revealed that choroidal thickness changes in the whole layer were significantly correlated with those in the inner (β = 0.51, P < 0.0001) and outer (β = 0.73, P < 0.0001) layers.

Conclusion

The inner choroidal layer significantly thinned with regression of MEWDS, correlating with the thinning of total choroidal thickness. These results suggest that MEWDS lesions in the choroid are likely to lie mainly in the inner layer.

Atypical white dot syndrome with choriocapillaris ischemia in a patient with latent tuberculosis

Background

White dot syndromes (WDS) are a group of idiopathic multifocal inflammatory conditions that can be recognized and distinguished by lesion morphology, other specific clinical features, imaging findings, and disease course. Our purpose is to describe an atypical case of WDS with choriocapillaris ischemia shown by multimodal imaging including swept-source OCT angiography (OCTA) in a 30-year-old woman with latent tuberculosis.

Findings

At presentation, visual acuity in the left eye was 20/500. Clinical findings included macular granularity, diffuse outer retinal discoloration with satellite yellow-white dots, and disc margin blurring. Fluorescein angiography showed early confluent areas of choroidal hypofluorescence and late perifoveal punctate hyperfluorescence. There was choroidal hypofluorescence in a geographic configuration throughout the indocyanine green angiography sequence. OCTA showed confluent geographic areas of loss of signal in the choriocapillaris. Work-up revealed latent tuberculosis. The patient received corticosteroids and prophylactic anti-tubercular treatment. Nine months later, visual acuity had improved to 20/20, and there were some residual retinal pigment epithelium changes.

Conclusion

Atypical WDS associated with choriocapillaris hypoperfusion may show features of multiple evanescent white dot syndrome and acute posterior multifocal placoid pigment epitheliopathy melting together.

Swept-source OCT in patients with multiple evanescent white dot syndrome

Background

Swept-source optical coherence tomography (SS-OCT) has a higher scanning rate and longer wavelength in comparison with spectral-domain OCT (SD-OCT), allowing an improved imaging of retinal vascular plexuses and choriocapillaris. The present two patients diagnosed with multiple evanescent white dot syndrome (MEWDS) underwent fundus autofluorescence (FAF), en-face SS-OCT, and SS-OCT angiography (OCTA) imaging, and its features were described and correlated.

Results

The clinical and imaging findings of both cases were consistent with the diagnosis of MEWDS. Color fundus photograph revealed subtle deep retinal white spots in the posterior pole and around the optic disk. FAF showed several hyperautofluorescent lesions corresponding topographically to the subtle deep retinal white lesions observed on color fundus photographs. Cross-sectional SS-OCT showed disruption of the ellipsoid zone (EZ) within the macular area in all study patients. En-face SS-OCT at the level of the outer retina showed lower reflectivity correspondent to the diffuse attenuation due to the EZ disruption on cross-sectional OCT. SS-OCTA demonstrated flow preservation within the retinal vasculature and choriocapillaris.

Conclusions

SS-OCT imaging allows a better visualization of the choriocapillaris, and its normal appearance in MEWDS may suggest that the outer retina and photoreceptors represent the primary site of inflammation.