Evolution of choroidal thickness over time and effect of early and sustained therapy in birdshot retinochoroiditis

Mechanisms, Pathophysiology and Current Immunomodulatory/Immunosuppressive Therapy of Non-Infectious and/or Immune-Mediated Choroiditis

Non-infectious choroiditis comprises immune-mediated diseases resulting from diverse pathophysiological mechanisms. These conditions are sub-divided into two main groups, (1) diseases of the choriocapillaris and (2) diseases of the choroidal stroma. The purpose of this study is to expose the pathophysiology of the most common diseases of both these groups and recommend the optimal immunomodulatory/immunosuppressive therapy of each analyzed condition based on literature data and data from our own centers. Material and Methods: Narrative review. In the group of choriocapillaritis entities or primary inflammatory choriocapillaropathies (PICCPs) including multiple evanescent white dot syndrome (MEWDS), acute posterior multifocal placoid pigment epitheliopathy (APMPPE), idiopathic multifocal choroiditis (MFC) and serpiginous choroiditis (SC), as well as secondary choriocapillaritides including acute syphilitic posterior multifocal placoid chorioretinitis (ASPMPC) and tuberculosis-related SC (TB-SC), were analyzed. In the group of stromal choroidites, HLA-A29 birdshot retinochoroiditis (BRC) and Vogt-Koyanagi-Harada (VKH) disease were included. For each entity a literature search, in the PubMed database, on treatment was performed and analyzed and the therapeutic attitudes of our own centers were presented. Management of immune-mediated choroiditis implies vigorous immunosuppressive therapy given in a prompt and prolonged fashion in most of these entities.

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.

Clinicopathology of non-infectious choroiditis: evolution of its appraisal during the last 2-3 decades from "white dot syndromes" to precise classification

Choroidal imaging investigation techniques were very limited until 2–3 decades ago.

Fluorescein angiography (FA) was not suited for the analysis of the choroidal compartment and B-scan ultrasonography did not provide enough accuracy. It was on this background that a purely phenomenological approach was attempted to classify these choroiditis diseases by regrouping them under the vague potpourri term of “white dot syndromes”. With the availability of precise investigational modalities of choroidal inflammation or choroiditis-induced lesions, such as indocyanine green angiography (ICGA), spectral domain optical coherence tomography (SD-OCT) and enhanced depth imaging optical coherence tomography (EDI-OCT) it became possible to better classify these diseases based on clinico-pathological mechanisms rather than on purely phenomenological observation.

Recently OCT-angiography has implemented the armamentarium of diagnostic techniques possibly also contributing to the classification of choroidal inflammatory diseases.

Based on pioneering pragmatism, the aim of this article was to give a clear classification of non-infectious choroiditis. Thanks to new imaging investigations of the choroid, it is now possible to classify and understand the diverse clinicopathological mechanisms in the group of non-infectious choroiditis entities.

HLA-A29 Birdshot Retinochoroiditis in Its 5th Decade: Selected Glimpses into the Intellectual Meanderings and Progresses in the Knowledge of a Long-Time Misunderstood Disease

The appraisal of HLA-A29 birdshot retinochoroiditis (BRC) was fraught with pitfalls and misunderstandings. Progress in investigational methods has led to better knowledge and management of the disease. Our aim was to assess some of the steps that have led to better characterisation of the clinical entity of BRC. We performed a literature search analysing the relevant progress in disease origin, investigational and imaging methods, clinicopathology and classification, diagnostic criteria and management. Following developments were judged essential in the better appraisal and understanding of the disease: (1) new immunopathological hypotheses regarding the role of endoplasmic reticulum peptidases, (2) the essential importance of HLA testing, (3) relevant imaging modalities among which indocyanine green angiography is crucial, (4) diagnostic criteria that allow early diagnosis and (5) need of an early prolonged, as well as aggressive treatment combining more than one immunosuppressive agent. Based on these findings it is now possible to better define BRC, an indolent however severe disease, unlike thought before, involving the choroidal stroma and the retina independently and concomitantly that can be diagnosed early thanks to indocyanine green angiography and should be treated early and relentlessly.

Classification of Non-Infectious and/or Immune Mediated Choroiditis: A Brief Overview of the Essentials

The choroid was poorly accessible to imaging investigation until the last decade of the last century. With the availability of more precise imaging methods such as indocyanine green angiography (ICGA) and, later, optical coherence tomography (OCT), enhanced depth OCT (EDI-OCT), and OCT angiography (OCTA), appraisal of choroidal inflammation has substantially gained in accuracy. This allowed to precisely determine which structures were touched in the different non-infectious choroiditis entities and made it possible to classify this group of diseases, ICGA signs, mainly hypofluorescent lesions, were identified and described. Previous publications have divided angiographic findings into two main sets of signs: (1) irregular “geographic” hypofluorescent areas corresponding to choriocapillaris non-perfusion and (2) round more regular, hypofluorescent dark dots more evenly distributed in the fundus corresponding to more deep choroidal stromal foci. These distinct findings allowed to subdivide and classify choroiditis into choriocapillaritis and stromal choroiditis. Additional signs were identified from EDI-OCT and OCTA examination supporting the classification of choroiditis into choriocapillaritis and stromal choroiditis. Results: Diseases involving principally the choriocapillaris included Multiple Evanescent White Dot Syndrome (MEWDS), Acute Posterior Multifocal Placoid Pigment Epitheliopathy (APMPPE), Idiopathic Multifocal Choroiditis (MFC), and Serpiginous Choroiditis (SC) as well as mixed forms. Diseases primarily involving the choroidal stroma included HLA-A29 Birdshot Retinochoroiditis (BRC), Vogt-Koyanagi-Harada disease (VKH), Sympathetic Ophthalmia (SO), and Sarcoidosis chorioretinitis (SARC). Thanks to new imaging investigations of the choroid, it is now possible to classify and understand the diverse clinicopathological mechanisms in the group of non-infectious choroiditis entities.

[Anatomic-functional correlations in birdshot chorioretinopathy: An observational single-center prospective study]

INTRODUCTION

The purpose of this study was to identify anatomic-functional correlations in patients with Birdshot chorioretinopathy in order to better understand the mechanisms of visual loss.

MATERIALS AND METHODS

We conducted a single-center observational prospective study at the Nantes University Medical Center including all patients followed for Birdshot chorioretinopathy between January 2019 and July 2019. The parameters studied were visual acuity, microperimetry, standard automated perimetry, SD-OCT, EDI-OCT, OCT-A, RNFL-OCT, wide-field fundus photographs, and fluorescein and ICG angiography.

RESULTS

Forty-four eyes were studied. A significant correlation was found between visual acuity and retinal thickness (P=0.002, r=0.44), but not choroidal thickness (P=0.16). A significant correlation was also observed between retinal sensitivity and total macular thickness (P<0.001, r=0.68) as well as inner retinal thickness (P<0.001, r=0.65), while the correlation was weaker with choroidal thickness (P=0.03, r=0.32). There was a weak correlation between retinal sensitivity and superficial capillary density (P=0.02, r=0.42) as well as deep capillary density (P=0.02, r=0.41). The peripheral hypo-autofluorescent zones correspond to the visual field defects, but these defects are larger than the hypo-autofluorescent zones. Patients with paracentral or peripheral field defects had a history of vasculitis more often than hypo-ICG spots.

DISCUSSION

We found significant correlations between functional parameters such as visual acuity and retinal sensitivity and retinal anatomic parameters, particularly the inner retina, while there was no correlation shown with choroidal anatomic parameters.

CONCLUSION

The main results of our study suggest a retinal rather than choroidal origin of the degradation of visual function in birdshot chorioretinopathy.

Changes in choroidal imaging parameters following adalimumab therapy for refractory noninfectious uveitis

PURPOSE

To evaluate the short-term change in choroidal structure following adalimumab (ADA) treatment in refractory noninfectious uveitis.

METHODS

This was a retrospective study of 33 eyes from 18 patients with refractory noninfectious uveitis. Subfoveal choroidal thickness (SFCT), the choroidal stromal index (CSI) defined as the proportion of stromal area to the total choroidal area were used as choroidal imaging parameters and were evaluated by enhanced depth imaging optical coherence tomography (EDI-OCT). The change in these parameters in the 2 months following initiation of ADA was analysed. A linear mixed-effect model was used to assess the effect of ADA treatment.

RESULTS

The causes of uveitis were Vogt-Koyanagi-Harada disease (VKHD) (42.4%), presumed autoimmune retinopathy (15.2%), others (12.1%) and unclassified (30.3%). In the analysis of all eyes, the SFCT was 309.7 ± 113.1 μm at baseline, 295.7 ± 114.5 μm at 1 month and 275.2 ± 98.8 μm at 2 months after ADA initiation (P < 0.001). The CSI was 0.275 ± 0.050 at baseline, 0.273 ± 0.068 at 1 month and 0.273 ± 0.046 at 2 months (P = 0.785). In the subgroup analysis, the SFCT decreased significantly from baseline to 2 months in VKHD eyes (P = 0.007) and unclassified eyes (P = 0.034). There was no significant change in CSI in either subgroup.

CONCLUSIONS

In the assessment of short-term response to ADA treatment in uveitic eyes, using EDI-OCT, the SFCT appears to be more effective as a choroidal imaging biomarker than the CSI, especially in VKHD eyes.

Advances and potential new developments in imaging techniques for posterior uveitis. Part 1: noninvasive imaging methods

The aim of this review was to identify the imaging methods at our disposal to optimally manage posterior uveitis at the present time. The focus was put on methods that have become available since the 1990s, some 30 years after fluorescein angiography had revolutionized imaging of posterior uveitis in particular imaging of the retinal vascular structures in the 1960s. We have focussed our review on precise imaging methods that have been standardized and validated and can be used universally thanks to commercially produced and available instruments for the diagnosis and follow-up of posterior uveitis. The first part of this imaging review will deal with noninvasive imaging methods, focusing on fundus autofluorescence and optical coherence tomography as well as recent developments in imaging of the posterior segment.

Low-grade "benign" birdshot retinochoroiditis: prevalence and characteristics

PURPOSE

To establish the prevalence, morphologic and functional characteristics and evolution of mild birdshot retinochoroiditis (BRC).

METHODS

Retrospective review of all BRC cases treated at the Centre for Ophthalmic Specialized Care, Lausanne, Switzerland, with at least 3 years of follow-up since the initial symptoms. Sub-Tenon's injection of triamcinolone was the first line of treatment if visual field changes were unilateral, with no additional treatment if visual field returned to normal. The percentage of patients who did not need systemic therapy was established, and the following parameters were evaluated: demographic characteristics, best-corrected visual acuity (BCVA), fundus photographs, fluorescein angiography (FA) and indocyanine green (ICGA) angiography frames and perimetry evaluation from initial visit to last follow-up.

RESULTS

Twenty cases of BRC were included in this study. Three of these patients (15%) received only local periocular therapy and qualified as mild BRC, with a mean follow-up of 9.3 years. The BCVA was 0.89 ± 0.25 at presentation and 1.0 ± 0.39 at last follow-up. Average visual field mean defect was 5.05 ± 3.27 at presentation and 1.78 ± 0.95 at last follow-up. Depigmented fundus lesions remained stable from presentation to last follow-up. Choroidal inflammatory activity monitored by ICGA decreased from 11.66 ± 3.44 at presentation to 4.25 ± 2.87 at last follow-up. FA revealed mild retinal vasculitis (2.25 ± 3.20) which remained stable (2.00 ± 4.00).

CONCLUSIONS

In our setting, 15% of BRC cases had a benign course, controlled with periocular treatment. It is important to identify such cases in order not to overtreat, exposing patients needlessly to potential side effects of aggressive and prolonged immunosuppressive treatment.

Optical coherence tomography: A guide to interpretation of common macular diseases

Optical coherence tomography is a quick, non invasive and reproducible imaging tool for macular lesions and has become an essential part of retina practice. This review address the common protocols for imaging the macula, basics of image interpretation, features of common macular disorders with clues to differentiate mimickers and an introduction to choroidal imaging. It includes case examples and also a practical algorithm for interpretation.