Mimickers of anterior uveitis, scleritis and misdiagnoses- tips and tricks for the cornea specialist

BACKGROUND

Anterior uveitis, inflammation of the anterior chamber and related structures, is a cohort of diseases that can present to almost any general or sub-specialty Ophthalmology practice. Its features classically involve anterior chamber cell and flare. Below the surface of these two signs exist a panoply of diagnoses. BODY: The purpose of this review is to provide a general framework for diagnoses of anterior uveitis that are often missed as well as non-uveitic pathologies that often mimic anterior uveitis. Diagnostic deviation in either direction can have vision-threatening and rarely life-threatening consequences for patients. Using a comprehensive literature review we have collected a broad spectrum of etiologies of anterior uveitis that are easily missed and non-uveitic pathologies that can masquerade as anterior uveitis.

CONCLUSIONS

We present a focused review on specific misdiagnosed anterior uveitis pathologies and some of the conditions that can masquerade as anterior uveitis and scleritis.

Coagulase-negative staphylococcal endophthalmitis: clinical severity and outcomes based on speciation

OBJECTIVE

To identify characteristics and visual outcomes of coagulase-negative staphylococci (CoNS) endophthalmitis in the era after the Endophthalmitis Vitrectomy Study.

DESIGN

Single-centre retrospective analysis.

PARTICIPANTS

Forty-two samples from 40 patients with documented CoNS endophthalmitis.

METHODS

Visual acuity outcomes of patients with CoNS endophthalmitis were assessed in relation to species and type of treatment instituted (e.g., pars plana vitrectomy [PPV] versus tap and injection of intravitreal antibiotics [T&I]). Strains were speciated using Gram and Giemsa staining and were further identified using API Staph and Biolog GEN III microplates. Genetic analysis was performed via polymerase chain reaction. Antibiotic susceptibility was assessed with disk diffusion.

RESULTS

Staphylococcus epidermidis was the most prevalent CoNS in our study. Cataract surgery and intravitreal injections were the most common sources for acute CoNS endophthalmitis. Eyes presenting with hand motion or better vision had similar mean final vision after either intravitreal antibiotics or PPV, whereas those with light perception or worse vision at onset had better outcomes after PPV only. Subanalysis showed that patients with S. epidermidis endophthalmitis (n = 39 eyes) had similar visual outcomes with either intravitreal injections or PPV regardless of visual acuity. Hypopyon and vitritis are not always present.

CONCLUSIONS

Patients with S. epidermidis endophthalmitis may benefit similarly from either early vitrectomy or intravitreal antibiotic injections regardless of visual acuity. This finding complements the management standards set forth by the Endophthalmitis Vitrectomy Study.

OCT Angiography in Noninfectious Uveitis: A Description of Five Cases and Clinical Applications

Background: Optical coherence tomography angiography (OCTA) is a noninvasive imaging modality used to analyze the retinochoroidal vasculature and detect vascular flow. The resulting images can be segmented to view each vascular plexus individually. While fluorescein angiography is still the gold standard for the diagnosis of posterior uveitis, it has limitations, and can be replaced by OCTA in some cases. Methods: This case series describes five patients with posterior noninfectious uveitis and their description by OCTA. Results: Cases included lupus retinopathy (n = 1) for which OCTA showed ischemic maculopathy as areas of flow deficit at the superficial and deep capillary plexus; choroidal granulomas (n = 1) with a non-detectable flow signal in the choroid; active punctate inner choroiditis and multifocal choroiditis (n = 1) with OCTA that showed active inflammatory chorioretinal lesions as non-detectable flow signals in choriocapillaris and choroid; dense type 2 inflammatory secondary neovascularization (n = 1) associated with active choroiditis; and acute posterior multifocal placoid pigment epitheliopathy (APMPPE) (n = 1) without flow abnormalities at the superficial and deep retinal plexuses but non-detectable flow at the levels of the choriocapillaris and choroid. Conclusions: Ophthalmologists can use OCTA to identify inflammatory changes in retinal and choroidal vasculature, aiding in the diagnosis, management, and monitoring of posterior uveitis.

Autofluorescent hyperreflective foci on infrared autofluorescence adaptive optics ophthalmoscopy in central serous chorioretinopathy

Purpose

To test the hypothesis that hyperreflective foci in central serous chorioretinopathy (CSCR) are autofluorescent and may represent macrophages that have engulfed outer retinal fluorophores from the retinal pigment epithelium (RPE) and photoreceptors.

Methods

Enrolled subjects underwent spectral domain and swept-source optical coherence tomography, adaptive optics flood-illumination, and adaptive optics scanning laser ophthalmoscopy (AOSLO), including near-infrared autofluorescence (AO-IRAF). For the AO-IRAF imaging, retinal fluorophores were excited using 795 nm light and collected in an emission band from 814 to 850 nm.

Results

In 2 of 3 eyes, a hyperautofluorescent signal was detected with an elliptical shape and punctate, granular aspects surrounded by a hypoautofluorescent halo. The size of these structures in the active case was measured to be 17 ± 4 μm in diameter, with at least 45 individual hyperautofluorescent foci identified from the AO-IRAF montage in the active stage of patient 2. In the asymptomatic case there were fewer structures visible (∼10) and their size was smaller (11 ± 4 μm). These hyper-AF foci were colocalized with hyperreflective foci on OCT and visible in simultaneously acquired confocal AOSLO images in active stage. The hyperautofluorescent foci in the patient with active CSCR disappeared coincident with clinical resolution.

Conclusion and importance

We show here the first AO-IRAF images from patients with CSCR, demonstrating hyper-autofluorescent punctate foci, colocalized with hyper-reflective foci on confocal AOSLO images and in OCT. The autofluorescence of these foci may be driven by the accumulation of photoreceptor and RPE fluorophores within macrophages during the active stage of the disease.

MULTIMODAL IMAGING OF MULTIFOCAL CHOROIDITIS WITH ADAPTIVE OPTICS OPHTHALMOSCOPY

PURPOSE

To describe longitudinal, anatomical, and functional alterations caused by inflammatory and neovascular lesions of idiopathic multifocal choroiditis/punctate inner choroidopathy using adaptive optics imaging and microperimetry.

METHODS

Longitudinal case study using multiple imaging modalities, including spectral-domain optical coherence tomography, fluorescein angiography, indocyanine green angiography, optical coherence tomography angiography, flood illumination adaptive optics, and microperimetry.

RESULTS

A 21-year-old myopic Asian man presented with blurred vision in the right eye. Clinical examination was notable for an isolated hypopigmented, perifoveal lesion in each eye. Multimodal imaging showed inflammatory lesions in the outer retina, retina pigment epithelium, and inner choroid lesions of both eyes. The right eye additionally exhibited active Type-2 macular neovascularization with loss of cone mosaic regularity that was associated with reduced sensitivity on microperimetry. The clinical picture was consistent with multifocal choroiditis/punctate inner choroidopathy. The patient was treated with oral steroids and three injections of intravitreal bevacizumab in the right eye. After therapy, imaging showed reestablishment of the cone mosaic on flood illumination adaptive optics and improvement in sensitivity on microperimetry.

CONCLUSION

Adaptive optics imaging and microperimetry may detect biomarkers that help to characterize the nature and activity of multifocal choroiditis lesions and to help monitor response to therapy. With timely intervention, structural abnormalities in the outer retina and choroid can be treated, and anatomical improvements precede improvements in visual function.

Clinical Features and Multimodal Imaging in Atypical Posterior Uveitis Secondary to Bartonella Henselae Infection

PURPOSE

To characterize an unusual presentation of infectious posterior uveitis using multimodal imaging, and discuss the clinical decision-making involved in diagnosis and treatment.

METHODS

Wide-field fundus photography, swept-source optical coherence tomography (OCT), swept-source OCT angiography, fluorescein angiography, and indocyanine green angiography.

RESULTS

This patient presented with cyclical fevers and blurry vision. Fundus examination revealed bilateral optic disc edema, macular intraretinal white spots and many scattered yellow-white chorioretinal lesions. Multimodal imaging characteristics suggested that many of these lesions represent choroidal granulomas. Extensive systemic workup was only notable for borderline elevated Bartonella henselae IgG titers (1:128), however convalescent IgG titers were elevated at 38 days (1:512) supporting the diagnosis of Bartonella chorioretinitis.

CONCLUSION

Ocular manifestations of Bartonella henselae infection are varied and may include choroidal granulomas. Multimodal imaging characteristics may help identify etiologies of infectious uveitis. Convalescent titers are important when evaluating patients with suspected Bartonellosis, especially patients with atypical presentations.

Near infrared autofluorescence imaging of retinal pigmented epithelial cells using 663 nm excitation

PURPOSE

Fundus autofluorescence (AF) using adaptive optics scanning laser ophthalmoscopy (AOSLO) enables morphometric analysis of individual retinal pigmented epithelial (RPE) cells. However, only a few excitation wavelengths in the visible and near-infrared have been evaluated. Visible light excitation (<600 nm) presents additional safety hazards and is uncomfortable for patients. Near-infrared excitation (>700 nm) overcomes those problems but introduces others, including decreased AF signal and cone signatures that obscure RPE structure. Here we investigated the use of an intermediate wavelength, 663 nm, for excitation and compared it to 795 nm.

METHODS

Subjects were imaged using AOSLO equipped with a detection channel to collect AF emission between 814 and 850 nm. Two light sources (663 and 795 nm) were used to excite the retinal fluorophores. We recorded 90 s videos and registered them with custom software to integrate AF images for analysis.

RESULTS

We imaged healthy eyes and an eye with pattern dystrophy. Similar AF microstructures were detected with each excitation source, despite ~4 times lower excitation power with 663 nm. The signal-to-noise values showed no meaningful difference between 663 nm and 795 nm excitation and a similar trend was observed for image contrast between the two excitation wavelengths.

CONCLUSIONS

Lower light levels can be used with shorter wavelength excitation to achieve comparable images of the microstructure of the RPE as have been obtained using higher light levels at longer wavelengths. Further experiments are needed to fully characterize AF across spectrum and determine the optimal excitation and emission bandwidths that balance efficiency, patient comfort, and efficacy.

Super U-Net: a modularized generalizable architecture

OBJECTIVE

To develop and validate a novel convolutional neural network (CNN) termed "Super U-Net" for medical image segmentation.

METHODS

Super U-Net integrates a dynamic receptive field module and a fusion upsampling module into the classical U-Net architecture. The model was developed and tested to segment retinal vessels, gastrointestinal (GI) polyps, skin lesions on several image types (i.e., fundus images, endoscopic images, dermoscopic images). We also trained and tested the traditional U-Net architecture, seven U-Net variants, and two non-U-Net segmentation architectures. K-fold cross-validation was used to evaluate performance. The performance metrics included Dice similarity coefficient (DSC), accuracy, positive predictive value (PPV), and sensitivity.

RESULTS

Super U-Net achieved average DSCs of 0.808±0.0210, 0.752±0.019, 0.804±0.239, and 0.877±0.135 for segmenting retinal vessels, pediatric retinal vessels, GI polyps, and skin lesions, respectively. The Super U-net consistently outperformed U-Net, seven U-Net variants, and two non-U-Net segmentation architectures (p < 0.05).

CONCLUSION

Dynamic receptive fields and fusion upsampling can significantly improve image segmentation performance.

Multimodal Imaging of Torpedo Maculopathy With Fluorescence Adaptive Optics Imaging of Individual Retinal Pigmented Epithelial Cells

Torpedo maculopathy (TM) is a rare congenital defect of the retinal pigment epithelium (RPE). The RPE is often evaluated clinically using fundus autofluorescence (AF), a technique that visualizes RPE structure at the tissue level from the intrinsic AF of RPE fluorophores. TM lesions typically emit little or no AF, but this macroscopic assessment is unable to resolve the RPE cells, leaving the organization of the RPE cell mosaic in TM unknown. We used fluorescence adaptive optics scanning laser ophthalmoscopy (AOSLO) to show here for the first time the microscopic cellular-level structural alterations to the RPE cell mosaic in TM that underlie the tissue-level changes seen in conventional clinical imaging. We evaluated two patients with TM using conventional clinical imaging techniques and adaptive optics (AO) infrared autofluorescence (IRAF) in AOSLO. Confocal AOSLO revealed relatively normal cones outside the TM lesion but altered cone appearance within it and along its margins in both patients. We quantified cone topography and RPE cell morphometry from the fovea to the margin of the lesion in case 1 and found cone density to be within the normal range across the locations imaged. However, RPE morphometric analysis revealed disrupted RPE cells outside the margin of the lesion; the mean RPE cell area was greater than two standard deviations above the normative range up to approximately 1.5 mm from the lesion margin. Similar morphometric changes were seen to individual RPE cells in case 2. Multi-modal imaging with AOSLO reveals that RPE cells are abnormal in TM well beyond the margins of the characteristic TM lesion boundary defined with conventional clinical imaging. Since the TM fovea appears to be fully formed, with normal cone packing, it is possible that the congenital RPE defect in TM occurs relatively late in retinal development. This work demonstrates how cellular level imaging of the RPE can provide new insight into RPE pathologies, particularly for rare conditions such as TM.

A New Method for Visualizing Drusen and Their Progression in Flood-Illumination Adaptive Optics Ophthalmoscopy

Purpose

Drusen are dynamic sub-RPE deposits that are risk factors for late-stage age-related macular degeneration (AMD). Here we show a new imaging method using flood-illumination adaptive optics (FIAO) that reveal drusen with high contrast and resolution.

Methods

A fovea-centered 4° × 4° FIAO image and eight surrounding images with gaze displaced by ±2° vertically and horizontally were acquired. Clinical color fundus and spectral-domain optical coherence tomography were acquired for clinical grading and comparison. Custom software registered overlapping FIAO images and fused the data statistically to generate a fovea-centered 4° × 4° gaze-dependent image. Our dataset included 15 controls (aged 31-72) and 182 eyes from 104 AMD patients (aged 56-92), graded as either normal aging (n = 7), and early (n = 12), intermediate (n = 108) and late AMD (n = 42); 27 had subretinal drusenoid deposits (SDDs), and 83 were imaged longitudinally.

Results

No gaze varying structures were detected in young eyes. In aging eyes with no evidence of age-related changes, putative drusen <20 µm in diameter were visible. Gaze-dependent images revealed more drusen and many smaller drusen than visible in color fundus images. Longitudinal images showed expansion and fusion of drusen. SDDs were lower contrast, and RPE atrophy did not yield a consistent signal.

Conclusions

Gaze-dependent imaging in a commercially available FIAO fundus camera combined with image registration and postprocessing permits visualization of drusen and their progression with high contrast and resolution.

Translational Relevance

This new technique offers promise as a robust and sensitive method to detect, map, quantify, and monitor the dynamics of drusen in aging and AMD.

Choriocapillaris: Fundamentals and advancements

The choriocapillaris is the innermost structure of the choroid that directly nourishes the retinal pigment epithelium and photoreceptors. This article provides an overview of its hemovasculogenesis development to achieve its final architecture as a lobular vasculature, and also summarizes the current histological and molecular knowledge about choriocapillaris and its dysfunction. After describing the existing state-of-the-art tools to image the choriocapillaris, we report the findings in the choriocapillaris encountered in the most frequent retinochoroidal diseases including vascular diseases, inflammatory diseases, myopia, pachychoroid disease spectrum disorders, and glaucoma. The final section focuses on the development of imaging technology to optimize visualization of the choriocapillaris as well as current treatments of retinochoroidal disorders that specifically target the choriocapillaris. We conclude the article with pertinent unanswered questions and future directions in research for the choriocapillaris.

Review of the Current Literature and Our Experience on the Value of OCT-angiography in White Dot Syndromes

PURPOSE

To describe the application of OCT-A in various posterior uveitis disorders in our experience and to compare it with the available literature.

METHODS

Eighteen eyes with the diagnoses of multifocal choroiditis (MFC), multifocal placoid pigment epitheliopathy (APMPPE), multiple evanescent white dot syndrome (MEWDS), tuberculous serpiginous-like choroiditis (SLC), serpiginous choroiditis (SC), and birdshot chorioretinopathy (BSCR) were studied.

RESULTS

We found flow void of the choriocapillaris in patients with APMPPE, SC, MFC, BSCR, and in SLC. In contrast, perfusion of the choriocapillaris seemed normal in patients with MEWDS.

CONCLUSIONS

We confirmed that OCT-A contributes new information on the physiopathology of white dot syndromes and inflammatory chorioretinopathies, notably on whether or not the choriocapillaris is involved. Comparing the OCT-A features allowed us to suggest that both APMPPE and SLC might be part of the same spectrum of inflammatory disease with primary involvement at the level of the choriocapillaris and secondary RPE damage.

Ophthalmology Practice During the Coronavirus Disease 2019 Pandemic: The University of Pittsburgh Experience in Promoting Clinic Safety and Embracing Video Visits

The coronavirus disease 2019 pandemic has led to widespread change as public health strategies for containment have emphasized social distancing and remaining at home. These policies have led to downscaled clinic volumes, cancellation of elective procedures, enhanced personal protective strategies in the clinic, and adoption of telemedicine encounters. We describe the evidence-based practical approach taken in our ophthalmology department to continue delivering eye care during the pandemic by rescheduling visits, enhancing clinic safety, and adopting virtual video encounters.

Microstructure of the retinal pigment epithelium near-infrared autofluorescence in healthy young eyes and in patients with AMD

Retinal pigmented epithelial (RPE) cells are essential for maintaining normal visual function, especially in their role in the visual cycle, and are thought to be one of the first cell classes affected by age-related macular degeneration (AMD). Clinical imaging systems routinely evaluate the structure of the RPE at the tissue level, but cellular level information may provide valuable RPE biomarkers of health, aging and disease. In this exploratory study, participants were imaged with 795 nm excitation in adaptive optics scanning laser ophthalmoscopy (AOSLO) to observe the microstructure of the near-infrared autofluorescence (AO-IRAF) from the RPE layer in healthy retinas and patients with AMD. The expected hexagonal mosaic of RPE cells was only sometimes seen in normal eyes, while AMD patients exhibited highly variable patterns of altered AO-IRAF. In some participants, AO-IRAF structure corresponding to cones was observed, as we have demonstrated previously. In some AMD patients, marked alterations in the pattern of AO-IRAF could be seen even in areas where the RPE appeared relatively normal in clinical imaging modalities, such as spectral domain optical coherence tomography (SD-OCT). AO-IRAF imaging using AOSLO offers promise for better detection and understanding of early RPE changes in the course of AMD, potentially before clinical signs appear.

Eye trauma in falls presenting to the emergency department from 2006 through 2015

Aims

To characterise the epidemiology of eye trauma in the event of falls presenting to the emergency departments (ED) in the USA.

Method

Retrospective cohort study. Nationwide Emergency Department Sample was used to analyse fall encounters presenting to the ED with eye trauma from 2006 to 2015. National estimates of the leading diagnoses were determined, and multivariable regression was used to determine the relationship between factors involved in fall encounters presenting with eye trauma.

Results

From 2006 to 2015, an estimated 87 991 036 fall encounters presented to the ED, of which 952 781 encounters had eye trauma as either a primary or secondary diagnosis. The overall incidence of fall encounters with eye trauma per 100 000 US population increased from 30.7 encounters in 2006 to 33.8 encounters per 100 000 population in 2014 with a decrease seen in 2015. Eye trauma, including vision-threatening type, was highest in females (n=500 520, 52.5%), elderly (n=400 209, 42%) and children (n=2 06 741, 21.7%). Elderly were more likely to have eye trauma in the setting of falls (adjusted OR (aOR) 2.06, 95% CI 2.02 to 2.11) and be admitted (aOR 1.89, 95% CI 1.86 to 1.91) than adults (reference). The leading types of eye trauma were contusion of orbital tissues (n=174 292, 18.3%), laceration of eyelid and periocular area (n=172 361, 18.1%) and orbital fractures (n=151 013, 15.8%).

Conclusions

Falls are preventable, yet the incidence of falls and resulting eye trauma are increasing despite our best efforts. As ophthalmologists, we should not only develop guidelines to recognise and counsel at-risk groups under our care but also strategies for prevention of eye trauma secondary to falls.

Eye-Related Emergency Department Visits and The Opioid Epidemic: a 10-Year Analysis

PURPOSE

To describe the epidemiology of Emergency Department (ED) visits related to opioid abuse with primary ophthalmic diagnoses in the United States (US).

METHODS

This retrospective cross-sectional study used National ED Sample (NEDS) (2006-2015), a representative sample of all US EDs, to analyze and compare the epidemiology of primary ophthalmic diagnoses in opioid abusers and a control group of non-opioid users. National incidence and descriptive statistics were calculated for demographics and prevalent diagnoses. Multivariable logistic regression was used to compare outcomes between primary ophthalmic diagnoses in opioid and non-opioid abusers.

RESULTS

An estimated 10,617 visits had a primary ophthalmic diagnosis and an accompanying opioid abuse diagnosis, and the incidence increased from 0.2 in 2006 to 0.6 per 100,000 US population in 2015. Opioid abuse group had more adults (6,747:63.5%) and middle-aged (3,361:31.7%) patients, while in controls adults (7,905,003:40.4%) and children (4,068,534:20.8%) were affected more. Leading etiologies were similar: traumatic and infectious etiologies were most common; however, opioid abuse patients had more severe ophthalmic diagnoses such as orbital fractures (8.4%), orbital cellulitis (7.4%), globe injury (3.4%) and endophthalmitis (3.2%) compared to controls. Patients in the opioid abuse group were also more likely to be admitted (adjusted Odds Ratio [aOR], 28.38 [95% CI, 24.50-32.87]).

CONCLUSIONS

In the era of opioid crisis, an increase in ED visits with ophthalmic complaints is seen, with increasing direct and indirect costs on the healthcare system. More research is needed to establish causality and devise strategies to lower this burden.

Classification and Quantification of Retinal Cysts in OCT B-Scans: Efficacy of Machine Learning Methods

The automatic segmentation of fluid spaces in optical coherence tomography (OCT) imaging facilitates clinically relevant quantification and monitoring of eye disorders over time. Eyes with florid disease are particularly challenging to segment, as the anatomy is often highly distorted from normal. In this context, we propose an end-to-end machine learning method consisting of near perfect detection of retinal fluid using random forest classifier and an efficient DeepLab algorithm for quantification and labeling of the target fluid compartments. In particular, we achieve an average Dice score of 86.23% with reference to manual delineations made by a trained expert.

Association of Optical Coherence Tomography Angiography of Collaterals in Retinal Vein Occlusion With Major Venous Outflow Through the Deep Vascular Complex

Importance

Analysis of collateral vessel formation following retinal vein occlusion may advance our understanding of the venous outflow anatomy in the macula.

Objective

To determine the location of collateral vessels with optical coherence tomography (OCT) angiography imaging.

Design, Setting, and Participants

Observational retrospective cohort study. Collateral vessel formation was studied with OCT angiography (OCTA) in patients with retinal vein occlusion (RVO). The study took place at 2 retinal practices (Vitreous Retina Macula Consultants of New York and Stein Eye Institute, University of California, Los Angeles), with patient records retrieved from March 2015 to August 2017. Data analysis was completed in November 2017.

Exposures

Collaterals identified with fundus photography and/or fluorescein angiography were analyzed with OCTA to determine their course through the superficial vascular plexus (SVP) and the deep vascular complex (DVC).

Main Outcomes and Measures

Collateral vessel pathways through the SVP and DVC were analyzed with cross-sectional and en face OCT and OCTA segmentation and color-coded volume renderings prepared from raw OCTA voxel data.

Results

From 23 eyes (22 branch and 1 hemispheric retinal vein occlusion ) of 23 patients (mean [SD] age, 73 [11] years), 101 collateral vessels were identified and analyzed (mean [SD], 4.4 [2.0]; range, 2-9 collateral per eye). On OCTA, the collaterals appeared as curvilinear dilated flow signals that connected veins across the horizontal raphe or veins on opposite sides of an occluded venous segment within the same retinal hemisphere. Of the 101 collaterals analyzed, all showed greater flow signal in the DVC, and all had some portion of their course identified within the DVC. No collaterals were found exclusively in the SVP. Volume renderings for 3 cases confirmed qualitatively that retinal collateral vessels course through the retina predominantly at the level of the DVC.

Conclusions and Relevance

Based on a limited number of cases, all collateral vessels associated with retinal vein occlusion were found to course through the DVC. The absence of collaterals isolated to the SVP supports a serial arrangement of the SVP and DVC, with venous drainage predominantly coursing through the DVC.

Choroidal imaging biomarkers

The choroid is the vascular coat of the eye, and its role has been studied in multiple chorioretinal disorders. Recent advancements in choroidal imaging techniques, including enhanced depth imaging optical coherence tomography, swept source optical coherence tomography, en face optical coherence tomography, and optical coherence tomography angiography have facilitated an in-depth analysis of the choroid. The gradual shift from manual to automated segmentation and binarization methods have led to precise and reproducible measurements of choroidal parameters. These qualitative and quantitative parameters, called choroidal imaging biomarkers, have evolved over the past decade from a simple linear subfoveal choroidal thickness to more complex 3D choroidal reconstruction, thus widening the spectrum encompassing multiple parameters. These biomarkers have provided a better understanding of the pathogenesis, are helpful in diagnostic dilemmas, and, in the future may also help to devise treatment options. The lack of normative data, absence of standardized parameters, and limitations of the imaging techniques, however, have led to ambiguity and difficulty in the interpretation of these variables. We attempt to address these lacunae in the literature and provide a basic understanding of the choroid in both health and disease using these choroidal biomarkers.

CRYSTALLINE RETINOPATHY AND RETINAL VASCULOPATHY IN CALCIFIC UREMIC ARTERIOLOPATHY (CALCIPHYLAXIS)

PURPOSE

To report the posterior segment and retinal vascular manifestations of calcific uremic arteriolopathy (calciphylaxis). Clinical findings are correlated with multimodal imaging results.

METHODS

Observational case report.

RESULTS

A 65-year-old white woman on hemodialysis was referred for assessment of poor vision bilaterally. Clinical examination demonstrated a crystalline retinopathy with stigma of previous retinal arterial occlusion. Fluorescein angiography revealed delayed retinal arterial filling bilaterally, sheathing of vessels, and peripheral nonperfusion. The crystals were hyperautofluorescent. Spectral domain and enhanced depth imaging optical coherence tomography localized the crystals within the retina with a predilection for the retinal arterial vasculature. The choriocapillaris was not involved. Two years prior, the patient developed necrotic skin lesions which were biopsied and confirmed the diagnosis of calciphylaxis.

CONCLUSION

Calcific uremic arteriolopathy is an extremely rare cause of thrombogenic microangiopathy in end-stage renal disease patients. Retinal arterial occlusion appears to be a rare but significant cause of visual loss in this disease and is likely to be consequent to crystalline deposition in the retinal vasculature.

Amplitude-scan classification using artificial neural networks

Optical coherence tomography (OCT) images semi-transparent tissues noninvasively. Relying on backscatter and interferometry to calculate spatial relationships, OCT shares similarities with other pulse-echo modalities. There is considerable interest in using machine learning techniques for automated image classification, particularly among ophthalmologists who rely heavily on diagnostic OCT. Artificial neural networks (ANN) consist of interconnected nodes and can be employed as classifiers after training on large datasets. Conventionally, OCT scans are rendered as 2D or 3D human-readable images of which the smallest depth-resolved unit is the amplitude-scan reflectivity-function profile which is difficult for humans to interpret. We set out to determine whether amplitude-scan reflectivity-function profiles representing disease signatures could be distinguished and classified by a feed-forward ANN. Our classifier achieved high accuracies after training on only 24 eyes, with evidence of good generalization on unseen data. The repertoire of our classifier can now be expanded to include rare and unseen diseases and can be extended to other disciplines and industries.

CLASSIFICATION OF HALLER VESSEL ARRANGEMENTS IN ACUTE AND CHRONIC CENTRAL SEROUS CHORIORETINOPATHY IMAGED WITH EN FACE OPTICAL COHERENCE TOMOGRAPHY

PURPOSE

To compare the prevailing patterns of Haller vessel arrangements at the posterior pole between healthy eyes and those with central serous chorioretinopathy (CSC) using en face optical coherence tomography.

METHODS

Eyes of normal subjects and patients with acute or chronic CSC underwent optical coherence tomography imaging (RTVue 100; Optovue Inc, Fremont, CA). En face sections at the level of the Haller layer were classified by two masked graders into five mutually exclusive morphologic categories (temporal herringbone, branched from below, laterally diagonal, double arcuate, and reticular). The relative prevalence of each Haller vessel arrangement pattern was determined for each phenotype.

RESULTS

Numbers of eyes examined were as follows: 154 eyes of 77 normal subjects; 41 eyes of 31 patients with acute CSC; and 39 eyes of 33 patients with chronic CSC. The mean age of participants was 44.4 ± 14.6 years for healthy subjects (M:F = 37:40), 48.5 ± 8.2 years (M:F = 24:7) for acute CSC, and 65.3 ± 13.1 years (M:F = 28:5) for chronic CSC. The relative prevalence of each Haller vessel arrangement pattern differed by phenotype. The temporal herringbone pattern was most prevalent in healthy eyes (49.2%), whereas a reticular pattern was most prevalent in eyes with acute and/or chronic CSC (combined, 48.8%).

CONCLUSION

A significant difference was observed in the prevalence of respective Haller vessel arrangement patterns between eyes of normal subjects and those of patients with either acute or chronic CSC. Although further study is needed to determine the mechanistic factors underlying these differences, and the hemodynamic implications, our data suggest that en face optical coherence tomography may find a formal role in choroidal disease classification.

Quantitative shadow compensated optical coherence tomography of choroidal vasculature

Conventionally rendered optical coherence tomography (OCT) images of the posterior segment contain shadows which influence the visualization of deep structures such as the choroid. The purpose of this study was to determine whether OCT shadow compensation (SC) alters the appearance of the choroid and the apparent choroidal vascularity index (CVI), an OCT-derived estimated ratio of luminal to total choroidal volume. All scans were shadow compensated using a previously published algorithm, binarized using a novel validated algorithm and extracted binarized choroid to estimate CVI. On 27 raw swept-source OCT volume-scans of healthy subjects, the effect of SC on CVI was established both qualitatively and quantitatively. In shadow compensated scans, the choroid was visualized with greater brightness than the neurosensory retina and the masking of deep tissues by retinal blood vessels was greatly reduced. Among study subjects, significant mean difference in CVI of -0.13 was observed between raw and shadow compensated scans. Conventionally acquired OCT underestimates both choroidal reflectivity and calculated CVI. Quantitative analysis based on subjective grading demonstrated that SC increased the contrast between stromal and luminal regions and are in agreement with true tissue regions. This study is warranted to determine the effects of SC on CVI in diseased eyes.

Understanding aneurysmal type 1 neovascularization (polypoidal choroidal vasculopathy): a lesson in the taxonomy of 'expanded spectra' - a review

The term aneurysmal type 1 neovascularization is derived from terminology, which is established in the literature but has fallen out of use. We believe that aneurysmal type 1 neovascularization accurately describes the lesions which define the entity known as polypoidal choroidal vasculopathy (PCV). Over the last three decades, the clinical spectrum of PCV has expanded to recognize the occurrence of the aneurysmal (polypoidal) lesions in different contexts, resulting in a complex and unwieldy taxonomy based sometimes on circumstantial findings rather than mechanistic considerations. Advances in multimodal imaging provides increasingly convincing evidence that the lesions which define various forms of PCV are indeed vascular and arise from type 1 neovascular networks. The understanding of PCV as type 1 neovascularization with aneurysms renews focus on the question as to why some patients with type 1 neovascularization develop aneurysms while others do not. Conceptual themes and potential for further study are discussed.

Idiopathic Acute Exudative Polymorphous Vitelliform Maculopathy: Clinical Spectrum and Multimodal Imaging Characteristics

PURPOSE

To describe clinical findings in patients with acute exudative polymorphous vitelliform maculopathy (AEPVM).

DESIGN

Retrospective, observational, multicenter case series review.

PARTICIPANTS

Consecutive patients diagnosed with idiopathic AEPVM.

METHODS

Review of clinical charts, multimodal imaging, electrophysiologic findings, and genetic findings in previously unpublished patients and review of the literature.

MAIN OUTCOME MEASURES

Clinical features of idiopathic AEPVM and differential diagnosis.

RESULTS

Eighteen patients (age range, 21-74 years) with typical features of AEPVM, including initial localized, serous detachments followed by the development of characteristic yellow-white deposits in the vitelliform space. Over time, this hyperautofluorescent material gravitated within the larger lesions, resulting in typical curvilinear deposits characteristic of later stages. Symptoms and clinical findings lasted from weeks to several years. Some patients showed previously undescribed features such as fluorescein-negative intraretinal cystic changes, choroidal neovascularization, serous retinal elevations mimicking retinal folds, increased choroidal thickness, lack of rapid visual recovery, and recurrence years after complete resolution of initial manifestations.

CONCLUSIONS

Acute exudative polymorphous vitelliform maculopathy can present with a more variable natural course than previously described. Paraneoplastic retinopathy and autosomal recessive bestrophinopathy closely resemble AEPVM, necessitating medical and hereditary evaluation to exclude these clinical possibilities. This series of patients with AEPVM expands the clinical spectrum of the disorder, including demographics, clinical manifestations, imaging features, natural course, and visual prognosis.

The Evolution of the Plateau, an Optical Coherence Tomography Signature Seen in Geographic Atrophy

Purpose

Histologic details of progression routes to geographic atrophy (GA) in AMD are becoming available through optical coherence tomography (OCT). We studied the origins and evolution of an OCT signature called plateau in eyes with GA and suggested a histologic correlate.

Methods

Serial eye-tracked OCT scans and multimodal imaging were acquired from eight eyes of seven patients with GA and plateau signatures over a mean follow-up of 7.7 years (range, 3.7–11.6). The histology of unrelated donor eyes with AMD was reviewed.

Results

Drusenoid pigment epithelial detachment (PED) on OCT imaging progressed into wide-based mound-like signatures with flattened apices characterized by a hyporeflective yet heterogeneous interior and an overlying hyperreflective exterior, similar to outer retinal corrugations previously ascribed to persistent basal laminar deposit (BLamD) but larger. These new signatures are described as “plateaus.” An initial increase of the PED volume and hyporeflectivity of its contents was followed by a decrease in PED volume and thinning of an overlying hyperreflective band attributable to the loss of the overlying RPE leaving persistent BLamD. Both imaging and histology revealed persistent BLamD with defects through which gliotic Müller cell processes pass.

Conclusions

Plateaus can be traced back to drusenoid PEDs on OCT imaging. We hypothesize that during progressive RPE atrophy, Müller cell extension through focal defects in the residual persistent BLamD may contribute to the heterogeneous internal reflectivity of these entities. The role of Müller cell activation and extension in the pathogenesis of AMD should be explored in future studies.

A Comparison Between Optical Coherence Tomography Angiography and Fluorescein Angiography for the Imaging of Type 1 Neovascularization

PURPOSE

To determine the sensitivity of the combination of optical coherence tomography angiography (OCTA) and structural optical coherence tomography (OCT) for detecting type 1 neovascularization (NV) and to determine significant factors that preclude visualization of type 1 NV using OCTA.

METHODS

Multicenter, retrospective cohort study of 115 eyes from 100 patients with type 1 NV. A retrospective review of fluorescein (FA), OCT, and OCTA imaging was performed on a consecutive series of eyes with type 1 NV from five institutions. Unmasked graders utilized FA and structural OCT data to determine the diagnosis of type 1 NV. Masked graders evaluated FA data alone, en face OCTA data alone and combined en face OCTA and structural OCT data to determine the presence of type 1 NV. Sensitivity analyses were performed using combined FA and OCT data as the reference standard.

RESULTS

A total of 105 eyes were diagnosed with type 1 NV using the reference. Of these, 90 (85.7%) could be detected using en face OCTA and structural OCT. The sensitivities of FA data alone and en face OCTA data alone for visualizing type 1 NV were the same (66.7%). Significant factors that precluded visualization of NV using en face OCTA included the height of pigment epithelial detachment, low signal strength, and treatment-naïve disease (P < 0.05, respectively).

CONCLUSIONS

En face OCTA and structural OCT showed better detection of type 1 NV than either FA alone or en face OCTA alone. Combining en face OCTA and structural OCT information may therefore be a useful way to noninvasively diagnose and monitor the treatment of type 1 NV.

Subretinal Hyperreflective Material Imaged With Optical Coherence Tomography Angiography

PURPOSE

The range of subretinal hyperreflective material (SHRM) seen in macular disease includes type 2 macular neovascularization, fibrosis, exudation, vitelliform material, and hemorrhage. The prognostic significance of SHRM has been evaluated retrospectively in clinical trials, but discriminating SHRM subtypes traditionally requires multiple imaging modalities. The purpose of this study is to describe optical coherence tomography angiography (OCTA) flow characteristics and artifacts that might help to distinguish SHRM subtypes.

DESIGN

Validity analysis.

METHODS

Patients with age-related macular degeneration (AMD), myopia, pachychoroid disease, and macular dystrophy, manifesting SHRM on optical coherence tomography (OCT), were recruited. Clinical chart review and multimodal imaging established the SHRM subtype. All patients underwent OCTA. OCT and OCTA images were examined together for (1) intrinsic flow, (2) retinal projection onto the anterior SHRM surface (strong, weak, absent), (3) retinal projection through SHRM onto retinal pigment epithelium (RPE), and (4) masking of choriocapillaris flow.

RESULTS

Thirty-three eyes of 25 patients were included (type 2 neovascularization ×3; fibrosis ×4; exudation ×10; hemorrhage ×5; vitelliform ×17). Mean age per eye was 76 years (standard deviation: 12). Intrinsic flow was strongest in type 2 neovascularization. Subretinal fibrosis showed limited flow in residual large-caliber vessels and branches. Flow was not detected within foci of exudation, hemorrhage, or vitelliform lesions. Retina-SHRM surface projection was strongest onto smooth-surfaced SHRM and weaker onto exudation. Retinal projection was weakest on the surface of vitelliform lesions. Retina-RPE projection was masked by dense hemorrhage and vitelliform material. In compound SHRM, OCTA distinguished between vascular and avascular components.

CONCLUSION

Optical coherence tomography angiography can distinguish vascular from avascular SHRM components. OCTA artifacts may distinguish certain avascular SHRM components.

Optical Coherence Tomography Evaluation of Valsalva-Induced Suprachoroidal Hemorrhage

Suprachoroidal hemorrhage is typically observed in patients with hypotony in the context of intraocular surgery and trauma. We report a rare presentation of suprachoroidal hemorrhage associated with emesis (Valsalva maneuver) in a myopic patient with few other identifiable risk factors. This diagnosis was confirmed with wide-field fundus photography and B-scan ultrasound and was localized to the suprachoroidal space using both enhanced depth and swept-source optical coherence tomography imaging. This case is unique in its presentation and demonstrates the utility of newer imaging techniques to localize hemorrhages using a multimodal approach. [Ophthalmic Surg Lasers Imaging Retina. 2016;47:674-676.].

Annular Lesions and Catenary Forms in Chronic Central Serous Chorioretinopathy

PURPOSE

To describe a series of patients exhibiting annular retinal pigment epithelial (RPE) lesions in the context of chronic central serous chorioretinopathy.

DESIGN

Retrospective comparative case series.

METHODS

Consecutive patients with chronic central serous chorioretinopathy were identified from the clinical practices of 3 retina specialists. A subset of patients exhibiting annular RPE lesions on fundus autofluorescence was included for chart review and examination of multimodal imaging (study group). Patients with alternative etiologies for neurosensory detachment or pigment epitheliopathy were excluded. A second consecutive cohort of patients, with acute central serous chorioretinopathy, was also examined for the presence of annular lesions (comparative group).

RESULTS

Sixty-seven patients with chronic central serous chorioretinopathy were identified. Fourteen eyes of 12 patients exhibited annular lesions (study eyes). Mean visual acuity of study eyes was 20/27 (logMAR 0.13, SD 0.11). Annular lesions were composed of hyperautofluorescent stellate lesions arranged in an open or closed ring with intervening foci of punctate hypoautofluorescence. Optical coherence tomography showed RPE hyperplasia at the perimeters of annular lesions with loss of ellipsoid reflectivity and preserved RPE at the lesion center. Annular lesions were confined to the posterior poles and appeared to have developed at the margins of chronic neurosensory detachment. Forty-three eyes of 30 patients with acute central serous chorioretinopathy comprised the comparative group and none of these eyes exhibited annular lesions.

CONCLUSIONS

Annular lesions occur in up to a fifth of patients with chronic central serous chorioretinopathy but carry a relatively good visual prognosis. Curvilinear RPE figures and demarcation lines are seen in various retinal conditions but the characteristics of annular lesions described here suggest that they are specific to chronic central serous chorioretinopathy.

Optical Coherence Tomography Angiography Reveals Mature, Tangled Vascular Networks in Eyes With Neovascular Age-Related Macular Degeneration Showing Resistance to Geographic Atrophy

BACKGROUND AND OBJECTIVE

To demonstrate a vascular pattern seen on optical coherence tomography angiography (OCTA) that appears to correlate with reduced rates of geographic atrophy (GA) in eyes receiving long-term anti-vascular endothelial growth factor (VEGF) treatment for neovascular age-related macular degeneration (AMD).

PATIENTS AND METHODS

Non-consecutive, retrospective cohort study. Patients were included if they had received more than 50 anti-VEGF injections during a period of at least 4 years for neovascular AMD in at least one eye, with absence or minimal progression of GA. Clinical charts and imaging were reviewed retrospectively; study eyes underwent OCTA.

RESULTS

Nine eyes of eight patients were included. Mean age was 82 years, and mean follow-up of study eyes 9.1 years; study eyes received a mean of 65.8 injections. OCTA revealed tangled networks of neovessels associated with type 1 lesions.

CONCLUSION

With prolonged anti-VEGF treatment, GA appears to occur less commonly in eyes with type 1 neovascularization. OCTA shows mature tangled vessels with substantial flow within type 1 lesions. Mature, tangled networks may be associated with a decreased likelihood of developing GA despite the presence of choriocapillaris atrophy.

PROGRESSION OF AGE-RELATED MACULAR DEGENERATION OVERLYING A LARGE CHOROIDAL VESSEL

PURPOSE

To describe a patient who showed progression of age-related macular degeneration along the course of an underlying large choroidal vessel.

METHODS

Retrospective case report.

RESULTS

An 84-year-old woman was diagnosed with age-related macular degeneration and followed for more than 6 years. Retinal pigment epithelial changes were more advanced in her right eye which had a thinner choroid than the fellow left eye. Multimodal imaging with swept-source optical coherence tomography showed that the progression of outer retinal and retinal pigment epithelial changes appeared to follow the course of a large choroidal vessel.

CONCLUSION

The authors hypothesize that large choroidal vessels can compress the overlying choriocapillaris, possibly leading to outer retinal ischemia, which subsequently could focally accelerate the course of age-related macular degeneration.

FOCAL CHOROIDAL EXCAVATION AND CHOROIDAL NEOVASCULARIZATION WITH ASSOCIATED PACHYCHOROID

PURPOSE

To report a case of focal choroidal excavation and choroidal neovascularization in the setting of pachychoroid disease.

METHODS

Multimodal imaging, including fundus photography, fundus autofluorescence, enhanced depth imaging optical coherence tomography, indocyanine green angiography, and en face structural and angiographic optical coherence tomography.

RESULTS

The authors describe a 39-year-old female with moderately high myopia presenting with focal choroidal excavation and associated choroidal neovascularization. Multimodal imaging demonstrated pachychoroid features with dilated choroidal vessels surrounding the lesion. Optical coherence tomography angiography showed Type 2 neovascularization.

CONCLUSION

Some cases of focal choroidal excavation and associated neovascularization may be related to structural abnormalities of the associated choroidal vasculature.

Optical Coherence Tomography Angiography of Shallow Irregular Pigment Epithelial Detachments In Pachychoroid Spectrum Disease

PURPOSE

To determine the proportion of shallow irregular pigment epithelial detachments in eyes with pachychoroid features that harbor neovascular tissue and to study the morphology of this tissue with optical coherence tomography (OCT) angiography.

DESIGN

Prospective consecutive cohort study.

METHODS

Patients with pachychoroid spectrum diagnoses and shallow irregular pigment epithelial detachment in at least 1 eye (study eye) were included. Charts and multimodal imaging were reviewed to determine a dye angiography detection rate for type 1 neovascularization in study eyes. All patients then underwent OCT angiography prospectively, followed by masked segmentation and grading.

RESULTS

Twenty-two eyes of 16 patients were included. Mean age was 71 (range 57-95) years. Mean subfoveal choroidal thickness was 381 μm (standard deviation: 141 μm). Four out of 22 study eyes (18%) exhibited polypoidal lesions. Dye angiography demonstrated specific features of neovascularization in 5 out of 17 eyes (29%) with suspected nonpolypoidal pachychoroid neovasculopathy. With OCT angiography, type 1 neovascular tissue was visualized in 21 out of 22 study eyes (95%).

CONCLUSIONS

Our data suggest that, in eyes with pachychoroid features, the finding of a shallow irregular pigment epithelial detachment on OCT has greater diagnostic value for type 1 neovascularization than previously thought and that dye angiography may underestimate the prevalence of neovascularization compared to OCT angiography.

Optical coherence tomographic angiography shows reduced deep capillary flow in paracentral acute middle maculopathy

INTRODUCTION

Paracentral acute middle maculopathy (PAMM) has been described as an ischemic lesion of the middle retinal layers with a characteristic lamellar hyper-reflective placoid appearance in the acute phase and thinning of the involved retinal layers in the chronic phase. Optical coherence tomographic angiography (OCTA) is a novel and non-invasive technique for imaging retinal capillary vasculature with en face segmentation capabilities.

METHOD

Case series. We describe two patients with PAMM who underwent clinical examination and multimodal imaging including OCTA.

RESULTS

In the first patient, who presented with PAMM secondary to acute cilioretinal artery occlusion, OCTA demonstrated reduction in flow in the deep capillary plexus (DCP). One month later, OCTA revealed a flow void due to thinning of the GCL, INL, and OPL and paradoxical apparent ONL thickening. Similar findings of focal retinal lamellar ectopia were seen in the second patient, who had an incidentally detected chronic PAMM lesion.

CONCLUSIONS

OCTA images the superficial and deep capillary plexi independently. PAMM is characterized by acute and chronic attenuation of the DCP flow signature. Focal lamellar ectopia in PAMM is discussed.

Ocular presentations of breast cancer

CONTEXT

Breast cancer is the most common malignancy in women, with increasing incidence in Europe and North America. The frequency of involvement of the eye and visual pathways is reported to be as high as 30% in patients with known metastatic disease. In some cases, ophthalmic involvement can be the first sign of metastatic spread. Metastasis occurs via the haematogenous route and predominantly involves the choroid. Metastases to other ocular structures, the orbit and the visual pathways have also been described. Paraneoplastic effects are rare but significant.

TREATMENTS

Different modalities are employed in the treatment of breast cancer and its metastases. These include chemotherapy and radiotherapy. The ocular adverse effects of these have been well described, but recently developed new treatment modalities, such as monoclonal antibodies, may have different side-effects. With the increasing incidence of breast cancer and the advent of new treatment strategies, the complications of the disease and the sequelae of therapy are highly relevant to both oncologists and ophthalmologists.

Management of intracorneal bleb after trabeculectomy for congenital glaucoma

PURPOSE

Congenital glaucoma is a well-recognized entity that can occur in the presence of anterior segment dysgenesis. Trabeculectomy is an accepted intervention in the management of congenital glaucoma. The surgical technique as well as complications is well described.

METHODS

This is a case report of a 3-month-old girl with anterior segment dysgenesis and glaucoma. She was referred post-trabeculectomy with persistent corneal opacity to be considered for penetrating keratoplasty and was found to have intrastromal corneal bleb.

RESULTS

Ultrasound biomicroscopy confirmed communication of the corneal bleb with the anterior chamber, and the bleb was treated by autologous blood injection at the trabeculectomy site, under acetazolamide cover.

CONCLUSIONS

We present evidence suggesting that abnormal structure was the etiologic basis for corneal bleb formation and describe our management of this previously unreported complication of trabeculectomy.