Multimodal imaging of adult-onset foveomacular vitelliform dystrophy

PRPH2-associated Retinal Diseases: A Systematic Review of Phenotypic Findings

PURPOSE

PRPH2-associated retinal diseases (PARD) result from pathogenic PRPH2 variants, primarily affecting photoreceptor outer segments and retinal pigment epithelium. The focus of this article is to review and discuss the phenotyping of PARD subtypes.

DESIGN

A systematic review METHODS: The review followed PRISMA 2020 guidelines with searches on PubMed, Medline, Web of Science, Google Scholar, and Cochrane Library. Eligible studies were those which discussed molecularly confirmed PARD or described associated diseases such as butterfly pattern dystrophy.

INCLUSION

cross-sectional, cohort, case-control studies, book chapters.

EXCLUSION

non-English, conference papers, non-peer-reviewed, or non-full text articles.

RESULTS

PARD is responsible for 25% of pattern dystrophy and up to 5% of inherited retinal dystrophies. There is clear evidence of phenotypic variability between individuals carrying the same pathogenic variant. Fundus autofluorescence, fluorescein angiography, optical coherence tomography, while in research adaptive optics reveal detailed phenotypic characteristics, notably in retinal pigment epithelium changes and photoreceptor disruption. The phenotypic of PARD variability presents diagnostic challenges, with phenotypic features often overlapping with other retinal diseases including age-related macular degeneration, Stargardt disease and retinitis pigmentosa.

CONCLUSION

This review emphasizes revising diagnostic criteria by incorporating more recent imaging techniques and confirming diagnosis with the use of genetic testing. Understanding phenotypic diversity and intrafamilial variability in PARD is crucial for developing new treatments and for patient prognosis and future research should focus on larger cohorts studying genotype-phenotype correlations.

Quantification of Fundus Autofluorescence Features in a Molecularly Characterized Cohort of More Than 3500 Inherited Retinal Disease Patients from the United Kingdom

Purpose

To quantify relevant fundus autofluorescence (FAF) image features cross-sectionally and longitudinally in a large cohort of inherited retinal diseases (IRDs) patients.

Design

Retrospective study of imaging data (55-degree blue-FAF on Heidelberg Spectralis) from patients.

Participants

Patients with a clinical and molecularly confirmed diagnosis of IRD who have undergone FAF 55-degree imaging at Moorfields Eye Hospital (MEH) and the Royal Liverpool Hospital (RLH) between 2004 and 2019.

Methods

Five FAF features of interest were defined: vessels, optic disc, perimacular ring of increased signal (ring), relative hypo-autofluorescence (hypo-AF) and hyper-autofluorescence (hyper-AF). Features were manually annotated by six graders in a subset of patients based on a defined grading protocol to produce segmentation masks to train an AI model, AIRDetect, which was then applied to the entire MEH imaging dataset.

Main Outcome Measures

Quantitative FAF imaging features including area in mm 2 and vessel metrics, were analysed cross-sectionally by gene and age, and longitudinally to determine rate of progression. AIRDetect feature segmentation and detection were validated with Dice score and precision/recall, respectively.

Results

A total of 45,749 FAF images from 3,606 IRD patients from MEH covering 170 genes were automatically segmented using AIRDetect. Model-grader Dice scores for disc, hypo-AF, hyper-AF, ring and vessels were respectively 0.86, 0.72, 0.69, 0.68 and 0.65. The five genes with the largest hypo-AF areas were CHM , ABCC6 , ABCA4 , RDH12 , and RPE65 , with mean per-patient areas of 41.5, 30.0, 21.9, 21.4, and 15.1 mm 2 . The five genes with the largest hyper-AF areas were BEST1 , CDH23 , RDH12 , MYO7A , and NR2E3 , with mean areas of 0.49, 0.45, 0.44, 0.39, and 0.34 mm 2 respectively. The five genes with largest ring areas were CDH23 , NR2E3 , CRX , EYS and MYO7A, with mean areas of 3.63, 3.32, 2.84, 2.39, and 2.16 mm 2 . Vessel density was found to be highest in EFEMP1 , BEST1 , TIMP3 , RS1 , and PRPH2 (10.6%, 10.3%, 9.8%, 9.7%, 8.9%) and was lower in Retinitis Pigmentosa (RP) and Leber Congenital Amaurosis genes. Longitudinal analysis of decreasing ring area in four RP genes ( RPGR, USH2A, RHO, EYS ) found EYS to be the fastest progressor at -0.18 mm 2 /year.

Conclusions

We have conducted the first large-scale cross-sectional and longitudinal quantitative analysis of FAF features across a diverse range of IRDs using a novel AI approach.

Adult-onset foveomacular vitelliform dystrophy: epidemiology, pathophysiology, imaging, and prognosis

Adult-onset foveomacular dystrophy (AOFVD) is a retinal pattern dystrophy that may affect up to 1 in 7,400 individuals. There is much that is unknown regarding this disease's epidemiology, risk factors for development, and rate of progression through its four stages. Advancements in retinal imaging over the past 15 years have enabled improved characterization of the different stages of AOFVD. These imaging advancements also offer new ways of differentiating AOFVD from phenotypically similar retinal diseases like age-related macular degeneration and Best disease. This review synthesizes the most recent discoveries regarding imaging correlates within AOFVD as well as risk factors for the development of AOFVD, complications of AOFVD, and treatment options. Our aim is to provide ophthalmologists a succinct resource so that they may offer clarity, guidance, and appropriate monitoring and treatments for their patients with suspected AOFVD.

Assessment of retinal vessel density in adult-onset foveomacular vitelliform dystrophy by optical coherence tomography angiography

BACKGROUND

To evaluate retinal thickness, area of foveal avascular zone (FAZ), flow area and flow density of choriocapillaris, vessel density of both superficial capillary plexus (SCP) and deep capillary plexus (DCP) of eyes with adult-onset foveomacular vitelliform dystrophy (AOFVD) using optical coherence tomography angiography (OCT-A) and compare the results with healthy controls.

METHODS

17 eyes of 14 patients diagnosed with AOFVD and 17 eyes of 17 healthy subjects were enrolled in this study. All patients underwent a complete ophthalmological examination and a 6 x 6 mm macular OCT-A scanning. Quantiative results of retinal thickness, retinal vessel density of SCP and DCP, FAZ area, flow area and flow density of choriocapillaris were analyzed.

RESULTS

No statistically significant differences were noted in the vessel density of the SCP, except for the parafoveal nasal sector (P = 0.048). Similarly, no statistically significant differences were observed in the vessel density of the DCP, except for the parafoveal (P = 0.037) and the parafoveal temporal (P = 0.048) sectors. The choriocapillaris flow area and the flow density were significantly lower in the patients with AOFVD than in the healthy controls (P = 0.001 for both). The mean FAZ area and the retinal thickness measurements were comparable in both groups.

CONCLUSIONS

Patients with AOFVD show vascular abnormalities that can be detected with OCT-A. OCT-A, as a noninvasive imaging modality, could provide a new perspective for understanding the pathophysiology of AOFVD and could also be useful in the follow-up of these patients and in the management of the disease progression.

Multicolor Imaging Characteristics of Best's Vitelliform Macular Dystrophy

A 40-year-old woman presented with vitellieruptive stage of Best's vitelliform macular dystrophy (BVMD) in the right eye and pseudohypopyon stage in the left eye. She underwent comprehensive ophthalmic examination and fundus imaging using multicolor (MC) imaging technology of Spectralis (Heidelberg Engineering, Heidelberg, Germany) spectral-domain-optical coherence tomography system. Composite MC imaging revealed larger area of retinal pigment epithelium atrophy in vitellierruptive stage of the disease in the right eye compared to color fundus photograph. Retinal elevation in the pseudohypopyon stage was better delineated on composite MC and blue reflectance images in the left eye. Subretinal lipofuscin was best seen in green reflectance and short-wave autofluorescence images. The present case reports the MC imaging features of BVMD.

Retinal pigment epithelium aperture: A late-onset complication in adult-onset foveomacular vitelliform dystrophy

Purpose:

The purpose of the study was to report aperture of retinal pigment epithelium (RPE) as a late complication and an unreported finding during the natural course of adult-onset foveomacular vitelliform dystrophy (AFVD).

Methods:

Four diagnosed cases of AFVD followed for a period ranging from 4 to 8 years. All patients had documented records of clinical examination, fundus autofluorescence and fluorescein angiography, and spectral domain-optical coherence tomography at regular intervals.

Results:

Besides the known stages in the natural course of AFVD, RPE aperture was noted as an additional finding during the vitelliruptive stage of the disease. The vitelliform material was noted beneath the disrupted RPE before disappearance. Accumulation of vitelliform material continued even after the vitelliruptive stage.

Conclusion:

RPE aperture may represent an ongoing process in the natural course of AFVD.

Methoxsalen-induced macular toxicity

Psoralen compounds such as methoxsalen are photosensitizer agents used in conjunction with ultraviolet A (UVA) radiation exposure as photochemotherapy (Psoralens and ultraviolet-A therapy [PUVA therapy]) for certain epidermal skin disorders such as psoriasis and vitiligo. Methoxsalen has been shown to be associated with premature cataract formation by forming adducts with lens proteins following oral administration and subsequent UVA exposure. Hence, the use of UV-filtering glasses is recommended during PUVA therapy sessions. Ocular tissues can be exposed to its photosensitizing effect with subsequent UV radiation exposure through sunlight if the patient was to be without protective eye glasses, potentially causing macular toxicity. Till date, there have been no reports in the literature of any posterior segment ocular toxicity arising from methoxsalen use. Here, we describe a case of a bilateral macular toxicity in a middle-aged male treated with methoxsalen for vitiligo.

Quantitative changes in flow density in patients with adult-onset foveomacular vitelliform dystrophy: an OCT angiography study

PURPOSE

To quantitatively compare the flow density, the retinal thickness, and the area of the foveal avascular zone (FAZ) between patients with adult-onset foveomacular vitelliform dystrophy (AOFVD) and a healthy controls.

METHODS

Thirteen eyes (eight patients) with AOFVD and 13 matched eyes (13 patients) without any ocular pathology were included in this study. A 6 × 6 mm optical coherence tomography angiography (OCTA) scan was performed for every included eye. The flow density (superficial retinal vascular layer, deep retinal vascular layer and choriocapillary layer), retinal thickness and FAZ (superficial retinal vascular layer and deep retinal vascular layer) were subsequently analyzed.

RESULTS

The mean flow density was decreased in the AOFVD patients in all measured vascular layers. The difference from the control group was statistically significant in the parafoveal sector of the deep retinal vascular layer (P = 0.02), and a clear trend was found in the superficial retinal vascular layer (P = 0.05). Both groups had comparable FAZs in the superficial and deep retinal vascular layers. The retinal thickness values were higher in the fovea (P = 0.840) and lower in the parafoveal sectors (P = 0.125). The difference was significant in the superior parafoveal sector (P = 0.034).

CONCLUSIONS

Flow densities as measured by OCTA are decreased in the superficial retinal vascular layer and the deep retinal vascular layer in patients with AOFVD. These findings could be helpful for diagnosing and understanding the pathogenesis of this disease.

The role of indocyanine green angiography imaging in further differential diagnosis of patients with nAMD who are morphologically poor responders to ranibizumab in a real-life setting

PurposeTo evaluate the neovascular age-related macular degeneration (nAMD) in patients who were morphologically poor responders to intravitreal ranibizumab (IVR) treatment using indocyanine green angiography (ICGA) for further investigation.MethodsThis was a cross-sectional, retrospective study. The patients with an initial diagnosis of nAMD who made through the clinical examination, optical coherence tomography, and fluorescein angiography imaging, and were treated with at least three monthly IVR injections that resulted with a morphological poor response, were included. ICGA was obtained from the patients and evaluated in regard to differential diagnosis of other macular diseases, which might mimic nAMD.ResultsThe study included 132 eyes of 117 patients. The mean age was 67.4±9.4 years. After ICGA imaging, 13 eyes (9.8%) were diagnosed as true nAMD, 74 eyes (56.1%) as polypoidal choroidal vasculopathy (PCV), 35 eyes (26.5%) as chronic central serous chorioretinopathy (CSC), 3 eyes (2.3%) as retinal angiomatous proliferation (RAP), 3 eyes (2.3%) as choroidal neovascularization secondary to CSC, 2 eyes (1.5%) as adult-onset vitelliform macular dystrophy, and 2 eyes (1.5%) as drusenoid pigment epithelial detachment with vitelliform material, respectively. The duration between the initial diagnosis and the revised diagnosis was 15.6±10.5 months in the non-AMD group, and the mean injection number of these patients was 6.6±4.4.ConclusionsMost of the nAMD patients who were thought to be morphologically poor responders to IVR were diagnosed as having non-AMD diseases via ICGA. A detailed differential diagnostic work-up is needed before considering these patients as poor responders.