Treatment of Acute Zonal Occult Outer Retinopathy With Intravitreal Steroids

The application of dexamethasone implants in uveitis treatment

Uveitis refers to a group of ocular inflammatory diseases that can significantly impair vision. Although systemic corticosteroid therapy has shown substantial efficacy in treating uveitis, extensive use of corticosteroids is associated with significant adverse effects. Recently, a biodegradable, sustained-release implant, namely dexamethasone intravitreal implant (Ozurdex), has been reported for treating non-infectious and infectious uveitis. This review aims to summarize the experiences with Ozurdex treatment across various forms of uveitis and to assist readers in understanding the appropriate timing and potential side effects of Ozurdex in uveitis treatment, thereby maximizing patient benefits in uveitis management.

Diagnosis, Mechanisms, and Differentiation of Inflammatory Diseases of the Outer Retina: Photoreceptoritis versus Choriocapillaritis; A Multimodal Imaging Perspective

Background and aim: Inflammatory diseases that affect the outer retina do so by different mechanisms. Some of them result from the direct, primary involvement of the outer retina (primary photoreceptoritis) such as acute zonal outer occult retinopathy (AZOOR). Others affect the photoreceptors secondarily due to the inflammatory involvement of the choriocapillaris. This results in choriocapillaris non-perfusion that damages the photoreceptors due to the ensuing ischaemia, a mechanism characterising primary inflammatory choriocapillaropathies (PICCPs) such as multiple evanescent white dot syndrome (MEWDS), idiopathic multifocal choroiditis (MFC), and others. Thanks to multimodal imaging (MMI), it is now possible to differentiate between these two mechanisms of outer retinal damage. The aim of this study is to determine the MMI characteristics that allow us to differentiate primary photoreceptoritis, including AZOOR, from PICCPs such as MEWDS and MFC. Methods: A series of eight PICCPs cases (five typical MEWDS and three typical active MFC cases) and four typical primary photoreceptoritis/AZOOR cases (five eyes) that had undergone complete MMI investigation, including fundus photography (FP), blue light fundus autofluorescence (BL-FAF), spectral domain optical coherence tomography (SD-OCT), OCT angiography (OCT-A, when available), fluorescein angiography (FA), and indocyanine green angiography (ICGA) were analysed, pointing out the differences that allow us to distinguish primary photoreceptoritis from PICCPs. Results: All primary photoreceptoritis/AZOOR cases showed (1) faint fundus pallor around the fovea, (2) BL-FAF hyperautofluorescence, (3) loss of photoreceptor outer segments (PROS) on SD-OCT, (4) absence of choriocapillary drop-out on OCT-A, (5) normal FA or faint FA hyperfluorescence, and (6) conserved ICGA fluorescence/no hypofluorescent areas; (1), (2), (3), and (5) indicated loss of photoreceptor outer segments, and (4) and (6) indicated conserved choriocapillaris circulation. For PICCPs, (a) fundus showed discreet white dots or none (in MEWDS) and punched-out scars in MFC, (b) BL-FAF hyperautofluorescence, (c) loss of PROS on SD-OCT, (d) FA faint hyperfluorescence in MEWDS, also minimal in active MFC lesions (e) in all cases ICGA hypofluorescent areas; (b) and (c) indicating loss of PROS, and (e) indicating choriocapillaris non-perfusion in all cases. The OCT-A did not show consistent findings with faint or no capillary drop-out in MEWDS and MFC. Conclusions: MMI combining the SD-OCT and BL-FAF clearly showed loss of PROS in both groups, while the ICGA determined whether this was due to choriocapillaris non-perfusion in PICCPs or whether the choriocapillaris was intact in case of primary photoreceptoritis. The FA and OCT-A were found to be less useful and/or less sensitive for the appraisal of both these entities.

Acute zonal occult outer retinopathy: optical coherence tomography angiography findings and treatment response

Acute zonal occult outer retinopathy (AZOOR) is a rare condition primarily affecting the outer retina based on electrophysiologic studies. In addition to characteristic fundus appearance, spectral domain optical coherence tomography and fundus autofluorescence are unique in diagnosing AZOOR. There are a few reports on optical coherence tomography anjiography (OCTA) in AZOOR disease. In this report, we present a case using multimodal imaging including OCTA and treatment response to combined systemic antiviral, antiinflammatory, and immunosuppressive drugs. En-face OCTA outer retinal slab may provide useful tips for diagnosis and treatment response.

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

INTRODUCTION

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

MATERIAL AND METHODS

Literature review.

RESULTS

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

CONCLUSION

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

Acute Zonal Occult Outer Retinopathy (AZOOR) Results from a Clinicopathological Mechanism Different from Choriocapillaritis Diseases: A Multimodal Imaging Analysis

Background and aim: AZOOR is a rare disease characterized by loss of zones of outer retinal function, first described by J Donald Gass in 1993. Symptoms include acute onset photopsias and subjective visual field losses. The syndrome is characterized by a normal fundus appearance, scotomas and electroretinographic changes pointing towards outer retinal dysfunction. Evolution, response to immunosuppressive treatment and outcome are difficult to predict. The aim of this small case series was to identify the morphological changes and sequence of events in AZOOR thanks to multimodal imaging. Methods: Charts of AZOOR patients seen in the Centre for Ophthalmic Specialized care (COS, Lausanne, Switzerland) were analyzed by multimodal imaging including fundus photography, fluorescein angiography (FA), indocyanine green angiography (ICGA), blue light fundus autofluorescence (BL-FAF) and spectral domain optical coherence tomography (SD-OCT) in addition to a complete ophthalmological examination including visual field testing and microperimetry, as well as OCT angiography (OCT-A) and ganglion-cell complex analysis when available. Cases and Results: Three AZOOR patients with a mean follow-up of 47 ± 25.5 months were included following the clinical definitions laid down by J Donald Gass. The primary damage was identified at the level of the photoreceptor outer segments with an intact choriocapillaris and retinal pigment epithelium (RPE) layer, these structures being only secondarily involved with progression of the disease. Conclusion: Although AZOOR has often been included within white dot syndromes, some of which are now known to be choriocapillaris diseases (choriocapillaritis entities), our findings clearly commend to differentiate AZOOR from entities such as MEWDS (Multiple evanescent white dot syndrome), APMPPE (Acute Posterior Multifocal Placoid Pigment Epitheliopathy), MFC (Multifocal Choroiditis) and others, as the damage to photoreceptors is primary in AZOOR (a retinopathy) and secondary in choriocapillaritis (a choriocapillaropathy).

Long term follow-up and effect of immunosuppression in acute zonal occult outer retinopathy

Acute zonal occult outer retinopathy (AZOOR) is a rare syndrome characterized by sudden onset of photopsia, scotomas, and abnormal electrophysiological tests, predominantly affecting young women. Although its pathogenesis remains unknown, auto-reactivity to retinal components is thought to mediate tissue damage. A 42-year-old woman presented with symptoms and examination consistent with the diagnosis of AZOOR. She was treated with azathioprine for 5 years. In spite of the immunosuppressive treatment, clear progression in the visual field, autofluorescence, electrophysiological tests and optical coherence tomography was observed. Treatment with intravenous immunoglobulins (IVIg) and subcutaneous Abatacept was subsequently started with little efficacy. Hereby, we present a case of progressive AZOOR despite aggressive immunosuppression with 10-year follow up. Currently, there is no consensus regarding management of AZOOR, and the convenience of administering aggressive immunosuppression remains uncertain.

Acute Idiopathic Blind Spot Enlargement and Acute Zonal Occult Outer Retinopathy: Potential Mimics of Neuro-Ophthalmic Disease

In 1988, William Hoyt, MD, et al described "acute idiopathic blind spot enlargement" (AIBSE) in 7 symptomatic patients who had no apparent abnormalities of the optic disc or surrounding retina. With the use of multifocal electroretinography, they showed that the scotoma was caused by occult retinal dysfunction. In 1992, J. Donald Gass, MD, described "acute zonal occult outer retinopathy" (AZOOR) in 13 patients who had sudden loss of often large zones of visual field without fundus abnormalities. Most patients developed zonal atrophy of retinal pigment epithelium and had no improvement in vision. Gass believed that AZOOR, multiple evanescent white dot syndrome, multifocal choroiditis, and AIBSE were all variants of the same disorder. Despite over 3 decades of numerous reports, the classification of these entities, their pathogenesis, and treatment remain controversial. AIBSE and AZOOR may be mistaken for an acute optic neuropathy, so it behooves the neuro-ophthalmologist to be familiar with these disorders. This review describes the initial recognition of AIBSE and its relationship to AZOOR.

Intravitreal Dexamethasone Implant as a Sustained Release Drug Delivery Device for the Treatment of Ocular Diseases: A Comprehensive Review of the Literature

Drug delivery into the vitreous chamber remains a great challenge in the pharmaceutical industry due to the complex anatomy and physiology of the eye. Intravitreal injection is the mainstream route of drug administration to the posterior segment of the eye. The purpose of this review is to assess the current literature about the widening use of the intravitreal 0.7 mg dexamethasone (Dex) implant, and to provide a comprehensive collection of all the ocular disorders that benefit from Dex administration. Although anti-vascular endothelial growth-factors (VEGFs) have been largely indicated as a first-choice level, the Dex implant represents an important treatment option, especially in selected cases, such as vitrectomized eyes or patients in whom anti-VEGF failed or are contraindicated. In this article, the safety profile as well as the list of the possible complications related to intravitreal Dex injection are also discussed.

Acute Zonal Occult Outer Retinopathy (AZOOR): a case report of regression following intravitreal dexamethasone (Ozurdex) implant

PURPOSE

To report the use of dexamethasone (Ozurdex, Allergan Inc.) intravitreal implant in the management of acute zonal occult outer retinopathy (AZOOR).

METHODS

Observational case report RESULTS:: A 63-year-old woman presented with a 10-year history of progressing bilateral, though asymmetric, visual impairment and scotomata with clinical and imaging findings compatible with AZOOR. The right eye had recently progressed rapidly until macular involvement occurred with loss of visual acuity. Under our observation progression toward the fovea in the left eye occurred, Ozurdex intravitreal implant treatment was offered and administered. Autofluorescence imaging documented resolution of the hyperautofluorescent borders and slight regression of the involved retina. An injection was repeated every 6 months for 3 injections, and after a follow-up period of 20 months after the first and 8 months after the last injection, no further signs of progression were observed in her left eye.

CONCLUSION

Dexamethasone implant effectively achieved regression of active disease in a patient with longstanding, progressive AZOOR.

Acute zonal occult outer retinopathy presenting as optic neuritis

Acute zonal occult outer retinopathy (AZOOR) is an outer retinal disorder characterized by the acute loss of visual functions. Herein, we report a case of AZOOR presenting features mimicking optic neuritis. A 17-year-old healthy male reported fogginess in the right eye for 2 weeks. His best-corrected visual acuity was 20/20 in both eyes. Results of a color vision test and pupillary reaction were unremarkable. Funduscopic examination revealed a subtle hyperemic disc surrounded by hyperpigmentation in the right eye. Visual field examination confirmed an enlarged blind spot in the affected eye. Fundus autofluorescence imaging revealed zonal hyperautofluorescence around the optic disc. Fluorescein angiography showed optic disc staining and a window defect in the retinal pigment epithelium. Optical coherence tomography demonstrated loss of the ellipsoid line at the corresponding hyperautofluorescent region. All these characteristics indicated a diagnosis of AZOOR. However, the prolonged P100 wave observed through visual-evoked potential examination, hyperintensity T2 signal at the retrobulbar optic nerve through magnetic resonance imaging, and mild hyperemic optic disc along with optic disc staining through fluorescein angiography resemble the characteristics of optic neuritis. Because the clinical features of AZOOR are similar to those of optic neuritis, ophthalmologists should be able to differentiate between these two diseases to achieve a timely and correct diagnosis.