Pattern of retinal dysfunction in acute zonal occult outer retinopathy

Acute Idiopathic Blind Spot Enlargement Syndrome (AIBSES) in the Era of OCT - a Review

There are only about 100 case reports on the Acute Idiopathic Blind Spot Enlargement Syndrome (AIBSES). This is characterised by the eponymous visual field loss in the blind spot area, acute onset photopsia, and funduscopically little or no change in the optic disc area, with conspicuous outer retinal bands on optical coherence tomography (OCT). Typical is the unilateral occurrence. Predominantly young women are affected. While previous reviews of AIBSES either predate the introduction of OCT or focus on differentiation from potentially related outer retinal conditions (e.g., multiple evanescent white dot syndrome and acute zonal occult outer retinopathy), the present review will concentrate on the current perspective and treatment strategies that have been developed and will aim to help increase awareness. Since the first description of AIBSES in the late 1980s, the introduction of OCT has simplified the diagnosis and characterisation of AIBSES as a disease of the outer retina. Nevertheless, misdiagnosis remains common in the spectrum of optic neuritis, as AIBSES may be ignored in differential diagnosis.

Paraneoplastic ocular syndrome: a pandora's box of underlying malignancies

Paraneoplastic syndromes affecting the visual system are a group of conditions that arise in the systemic malignancy framework. In this review, we have provided a detailed and comprehensive overview of the published literature on the various ophthalmic paraneoplastic manifestations. A systematic review of many databases has been performed to identify ample literature on the paraneoplastic syndromes related to ophthalmology. We have discussed here the clinical features, pathogenesis, and treatment strategies of various ophthalmic paraneoplastic syndromes. It can be challenging to distinguish these disorders from their non-paraneoplastic counterparts and to determine the appropriate systemic assessment for the tumour responsible, to have a proper approach towards the management of the syndrome. METHOD: We searched PubMed, Science Direct and Journal of Ophthalmology for studies published in English between 1995 and April 2020, incorporating the general search term "paraneoplastic ocular syndrome" with connecting terms relevant to subheadings-e.g. Key search terms were cancer-associated retinopathy, (CAR), melanoma-associated retinopathy, (MAR), paraneoplastic retinopathy, autoimmune retinopathy, autoimmune-related retinopathy, and optic neuropathy, (ARRON), acute zonal occult outer retinopathy, (AZOOR), paraneoplastic vitelliform maculopathy, paraneoplastic vitelliform retinopathy, bilateral diffuse uveal melanocytic proliferation, (BDUMP), paraneoplastic optic neuropathy, (PON), polyneuropathy, organomegaly, endocrinopathy, monoclona gammopathy, and skin changes syndrome (POEMS) and various other terms. References from identified studies have been reviewed and included if deemed appropriate, valid, and scientifically important. If referenced in a selected English paper, we contemplated papers in other languages too. We preferentially selected papers that have been published in the last 10 years, but we have included relevant older references.

Anti-retinal autoantibodies in myopic macular degeneration: a pilot study

AIM

The aim of this study is to evaluate the frequency and types of anti-retinal autoantibodies (ARAs) in highly myopic patients and to explore any association between ARAs and the severity of myopic macular degeneration (MMD).

METHODS

This was a clinic-based study of 16 patients with high myopia (spherical equivalent worse than -6 dioptres or axial length (AL) ≥ 26.5 mm) recruited from the High Myopia clinic of the Singapore National Eye Centre. MMD was graded from fundus photographs according to the Meta-analysis for Pathologic Myopia (META-PM) classification. Severe MMD was defined as META-PM category 3 or 4. AL and logarithm of the minimal angle of resolution (logMAR) best corrected visual acuity (BCVA) were measured. Sera were obtained from subjects and analysed for the presence of ARAs with the western blot technique.

RESULTS

The mean AL was significantly longer in patients with severe MMD (n = 8) than those without severe MMD (n = 8) (31.50 vs. 28.51, p = 0.005). There was at least one ARA identified in all patients. The most common ARA was anti-carbonic anhydrase II (anti-CAII), present in nine patients (56.3%). Anti-CAII was detected in more patients with severe MMD than those without (75 vs. 37.5%, p = 0.32). LogMar BCVA was also worse in subjects with anti-CAII (0.5 ± 0.38 vs. 0.22 ± 0.08, p = 0.06). The number of ARAs significantly correlated with increasing AL (r = 0.61, p = 0.012).

CONCLUSIONS

ARAs are prevalent in patients with high myopia, and this increases with increasing AL. In particular, anti-CAII antibodies were highly prevalent in patients with severe MMD, suggesting that ARAs may be associated with MMD. Further studies are necessary to confirm these observations in larger cohorts.

Electroretinogram abnormalities in non-infectious uveitis often persist

PURPOSE

In uveitis, a prolonged implicit time of the cone b-wave is a characteristic electroretinogram (ERG) abnormality. We investigated whether this can improve or deteriorate over time and which clinical factors are associated with change.

METHODS

Prospective cohort study. Patients with a non-infectious uveitis were included. An ERG was measured in the first year of uveitis onset and a follow-up ERG one year later. Changes in the implicit time of the cone b-wave were investigated in relation to clinical parameters including the following: demographics, uveitis characteristics, treatment, best-corrected visual acuity, optical coherence tomography parameters and fluorescein angiography scores.

RESULTS

Of 98 eyes (63 patients), 40 showed a prolonged cone b-wave on the first ERG, which improved in 10 eyes. Eyes with an improved ERG more often had a panuveitis with initially a higher incidence of cells in the anterior chamber during the first ERG, which resolved at the time of their follow-up ERG. Five of the 58 eyes with a normal first ERG had a deteriorated follow-up ERG. These eyes had more frequently an active uveitis at the time of the follow-up ERG. Of the 78 eyes with a stable cone b-wave, 16 had a quiescent inflammation during follow-up. There were no differences in age or treatment.

CONCLUSION

In most patients with non-infectious uveitis, ERG abnormalities appear to be irreversible, even when the inflammation becomes quiescent. However, some ERGs improved, which was associated with reduction in inflammation of the anterior chamber due to panuveitis. In contrast, a worsened ERG was associated with a persistence of inflammation.

Unilateral pigmentary retinopathy: a retrospective case series

PURPOSE

To review the clinical characteristics and address the aetiology in a group of patients presenting with unilateral retinal pigmentary changes, best described as unilateral pigmentary retinopathy (UPR).

METHODS

The cohort of 42 patients was identified retrospectively from the Moorfields Eye Hospital electrophysiology database. All had undergone full-field [electroretinography (ERG)] and pattern electroretinography (PERG), with 13 additionally having multifocal ERG (mfERG). The clinical findings, fundus photographs and fundus autofluorescence (AF) images were reviewed.

RESULTS

All index eyes showed ERG evidence of generalized photoreceptor dysfunction with most showing a similar degree of rod and cone involvement. However, although the fellow eyes all had a normal fundus examination, there were bilateral but asymmetrical ERG abnormalities in eight patients and a further four patients had PERG evidence of macular dysfunction in the fellow eye. A relevant medical history or the diagnosis of an ophthalmologic entity that might be related to the unilateral fundus changes was ascertained in 15 cases (~36%) including acute zonal occult outer retinopathy, trauma, systemic malignancy or autoimmune disease, retinal vasculitis, presumed pregnancy-related choroidal ischaemia and meningitis. Two patients had a family history of retinitis pigmentosa (RP; 4.8%).

CONCLUSION

The underlying aetiology in most cases of UPR cannot accurately be identified, but an heritable cause is unlikely. Aspects of the history clearly suggest an acquired disorder in some patients. Twenty-five patients (60%) with nongenetic UPR did not adhere to the pattern of rod greater than cone dysfunction that occurs in RP (rod-cone dystrophy), and the pattern of rod > cone dysfunction seen in true RP is thus not a feature of most patients with UPR.

Multimodal imaging signatures in a case of acute zonal occult outer retinopathy

Acute zonal occult outer retinopathy (AZOOR) is a retinal disease characterized by a slow onset loss of retinal function with minimally evident fundus changes. Patients with AZOOR present with initially progressive scotoma and photopsia. Its pathogenesis has not been definitively determined as of yet. Characteristically, the extent of the visual field defect is unexplained by fundus examination, but there is marked retinal dysfunction, which is evident on multimodal imaging and electrophysiological testing. We herein describe multimodal imaging signatures of AZOOR, in a patient of Indian origin, highlighting the hitherto unreported multicolor channels and near-infrared autofluorescence.

Acute Zonal Cone Photoreceptor Outer Segment Loss

Importance

The diagnostic path presented narrows down the cause of acute vision loss to the cone photoreceptor outer segment and will refocus the search for the cause of similar currently idiopathic conditions.

Objective

To describe the structural and functional associations found in a patient with acute zonal occult photoreceptor loss.

Design, Setting, and Participants

A case report of an adolescent boy with acute visual field loss despite a normal fundus examination performed at a university teaching hospital.

Main Outcomes and Measures

Results of a complete ophthalmic examination, full-field flash electroretinography (ERG) and multifocal ERG, light-adapted achromatic and 2-color dark-adapted perimetry, and microperimetry. Imaging was performed with spectral-domain optical coherence tomography (SD-OCT), near-infrared (NIR) and short-wavelength (SW) fundus autofluorescence (FAF), and NIR reflectance (REF).

Results

The patient was evaluated within a week of the onset of a scotoma in the nasal field of his left eye. Visual acuity was 20/20 OU, and color vision was normal in both eyes. Results of the fundus examination and of SW-FAF and NIR-FAF imaging were normal in both eyes, whereas NIR-REF imaging showed a region of hyporeflectance temporal to the fovea that corresponded with a dense relative scotoma noted on light-adapted static perimetry in the left eye. Loss in the photoreceptor outer segment detected by SD-OCT co-localized with an area of dense cone dysfunction detected on light-adapted perimetry and multifocal ERG but with near-normal rod-mediated vision according to results of 2-color dark-adapted perimetry. Full-field flash ERG findings were normal in both eyes. The outer nuclear layer and inner retinal thicknesses were normal.

Conclusions and Relevance

Localized, isolated cone dysfunction may represent the earliest photoreceptor abnormality or a distinct entity within the acute zonal occult outer retinopathy complex. Acute zonal occult outer retinopathy should be considered in patients with acute vision loss and abnormalities on NIR-REF imaging, especially if multimodal imaging supports an intact retinal pigment epithelium and inner retina but an abnormal photoreceptor outer segment.

ACUTE ZONAL OCCULT OUTER RETINOPATHY: Structural and Functional Analysis Across the Transition Zone Between Healthy and Diseased Retina

PURPOSE

To assess structure and function across the transition zone (TZ) between relatively healthy and diseased retina in acute zonal occult outer retinopathy.

METHODS

Six patients (6 eyes; age 22-71 years) with acute zonal occult outer retinopathy were studied. Spectral-domain optical coherence tomography, fundus autofluorescence, near-infrared reflectance, color fundus photography, and fundus perimetry were performed and images were registered to each other. The retinal layers of the spectral-domain optical coherence tomography scans were segmented and the thicknesses of two outer retinal layers, that is, the total receptor and outer segment plus layers, and the retinal nerve fiber layer were measured.

RESULTS

All eyes showed a TZ on multimodal imaging. On spectral-domain optical coherence tomography, the TZ was in the nasal retina at varying distances from the fovea. For all eyes, it was associated with loss of the ellipsoid zone band, significant thinning of the two outer retinal layers, and in three eyes with thickening of the retinal nerve fiber layer. On fundus autofluorescence, all eyes had a clearly demarcated peripapillary area of abnormal fundus autofluorescence delimited by a border of high autofluorescence; the latter was associated with loss of the ellipsoid zone band and with a change from relatively normal to markedly decreased or nonrecordable visual sensitivity on fundus perimetry.

CONCLUSION

The results of multimodal imaging clarified the TZ in acute zonal occult outer retinopathy. The TZ was outlined by a distinct high autofluorescence border that correlated with loss of the ellipsoid zone band on spectral-domain optical coherence tomography. However, in fundus areas that seemed healthy on fundus autofluorescence, thinning of the outer retinal layers and thickening of the retinal nerve fiber layer were observed near the TZ. The TZ was also characterized by a decrease in visual sensitivity.

The clinical characteristics and prognosis of acute zonal occult outer retinopathy

PURPOSE

This prospective observational case series study aimed to observe the clinical characteristics of acute zonal occult outer retinopathy (AZOOR) and its prognosis in Chinese Han patients.

METHODS

Six eyes of 5 female patients diagnosed with AZOOR were followed up for 4 months to observe the natural disease course. All enrolled subjects underwent a series of ocular examinations at the onset and each return visit, including best corrected visual acuity (BCVA), split lamp microscopy, fundus photography, optical coherence tomography (OCT), perimetry, multifocal electroretinogram and fundus fluorescein angiography.

RESULTS

Over the follow-up, all enrolled patients recovered on BCVA, perimetry and OCT in different degrees. Among them, one patient recovered completely since the ocular examination results returned to normal.

CONCLUSION

AZOOR is a rare ocular disorder in Chinese population. Our results demonstrated that visual functions of enrolled patients significantly improved spontaneously, indicating that Chinese female Han patients with AZOOR have good visual outcomes during the follow-up period without any specific managements.

Autoimmune retinopathy: A case report from India

A first case report of autoimmune retinopathy (AIR) from India. A middle-aged female patient presented with subacute loss of vision in both eyes. Clinical examination revealed a near normal fundus in both the eyes. A presumed diagnosis of nonparaneoplastic AIR was made based on clinical features and suggestive investigations. Early detection and management with steroids or immunosuppression may be beneficial to patients with AIR.

Idiopathic multifocal choroiditis with outer retinal or chorioretinal atrophy

PURPOSE

To report thirteen cases of idiopathic multifocal choroiditis with discrete chorioretinal lesions who were found to have zonal, multizonal, or diffuse outer retinal or chorioretinal atrophy.

METHODS

A retrospective observational case series using multimodal imaging including high-definition optical coherence tomography, fundus autofluorescence imaging, and fluorescein and indocyanine green angiography.

RESULTS

Twenty-one eyes in 13 patients with idiopathic multifocal choroiditis were found to have zonal, multizonal, or diffuse outer retinal or chorioretinal atrophy visualized using multimodal imaging. Thirteen eyes presented with diffuse disease, six eyes with multizonal, and two with zonal atrophy. Patterns of atrophy included zones surrounding the optic nerve, multiple geographic zones in the mid and far periphery, and a diffuse peripheral pattern with relative sparing of the central macula until later in the course of disease. Eleven of the 13 patients were treated with topical, periocular, or systemic corticosteroids, and 1 patient was also treated with systemic immunomodulatory treatment. The atrophic changes progressed over an average of 8 years of follow-up in 10 eyes despite therapy.

CONCLUSION

Idiopathic multifocal choroiditis can present with an uncommon pattern of zonal, multizonal, or diffuse outer retinal or chorioretinal atrophy as part of its clinical spectrum. The severity, extent, and progression of these atrophic changes are best appreciated using multimodal diagnostic imaging.

Changes in outer retinal microstructures during six month period in eyes with acute zonal occult outer retinopathy-complex

Purpose

To study the changes in the outer retinal microstructures during a six month period after the onset of acute zonal occult outer retinopathy (AZOOR)-complex by spectral-domain optical coherence tomography (SD-OCT).

Methods

Seventeen eyes of 17 patients with the AZOOR-complex were studied. The integrity of the external limiting membrane (ELM), ellipsoid zone (EZ; also called the inner/outer segment junction), and interdigitation zone (IDZ; also called the cone outer segment tips) were evaluated in the SD-OCT images obtained at the initial visit and at six months. The three highly reflective bands were divided into three types; continuous, discontinuous, and absent. The integrity of the outer nuclear layer (ONL) was also assessed.

Results

Among the three highly reflective bands, the IDZ was most altered at the initial visit and least recovered at six months. Fifteen of 17 eyes (88%) had a recovery of at least one of the three bands at six months in the retinal area where the ONL was intact, and these areas showed an improvement of visual field. Three eyes (18%) had retinal areas where the ONL was absent at the initial visit, and there was no recovery in both the retinal structures and visual fields in these areas.

Conclusions

Our results indicate that more than 85% eyes with AZOOR-complex show some recovery in the microstructures of the outer retina during a six month period if the ONL is intact. We conclude that SD-OCT is a useful method to monitor the changes of the outer retinal microstructure in eyes with the AZOOR-complex.

Gender differences in birdshot chorioretinopathy and the white dot syndromes: do they exist?

Inflammatory conditions that affect the posterior pole are diverse. Specifically, birdshot chorioretinopathy and the white dot syndromes present with multiple white dots in the fundus. These diseases appear to affect similar age groups but there is question as to whether or not a difference exists between the genders. This review summarizes the current studies on birdshot chorioretinopathy and the white dot syndromes as they are related to gender, exploring the differences, if any, which may exist between prevalence, clinical presentation, and treatment response for these diseases. Though the specific etiology of these diseases remains unclear, future treatments may be guided as to how these diseases affect the sexes differently.

Autoimmune retinopathies: a report of 3 cases

PURPOSE

To describe 3 representative cases of autoimmune retinopathy (AIR).

METHODS

Clinical records of patients with a diagnosis of AIR were analyzed for demographic data, clinical findings, ancillary and laboratory tests, and treatment employed.

RESULTS

Three female patients diagnosed with AIR had bilateral reduction of electroretinogram amplitudes and elevation of visual field threshold within the central 30 degrees of the visual field that was disproportionately more severe than the clinical findings of retinal degeneration. The diagnoses were cancer-associated retinopathy, non-neoplastic AIR, and hereditary retinal dystrophy with secondary inflammation. Optic nerve involvement was also present in all cases. The patient with non-neoplastic AIR was successfully treated with systemic corticosteroids and immunomodulatory agents.

CONCLUSION

High index of suspicion is essential for an early diagnosis of AIR. Visual function and electrophysiological tests should be included in the initial workup of patients who present with suggestive clinical signs and symptoms of AIR.

Acute Zonal Occult Outer Retinopathy: Vision Loss in an Active Duty Soldier

Objective. To describe a case of acute zonal occult outer retinopathy (AZOOR) in an active duty patient.Methods. In this paper we studied fundus photographs, optical coherence tomograph, Humphrey visual field 30-2, fundus autofluorescence images, fluorescein angiograms, and electroretinography.Results. Exam findings on presentation: a 34-year-old American Indian female presented with bilateral photopsias, early RPE irregularity, and an early temporal visual field defect. Progression RPE damage and visual field defect along with ERG findings support final diagnosis of AZOOR.Conclusion. AZOOR may initially be identified as a broader category of disease called the “AZOOR complex of disorders”. Specific visual field defects, ERG results, and clinical exam findings will help distinguish AZOOR from other similar disorders.

Hyperautofluorescent ring in autoimmune retinopathy

PURPOSE

To report the presence of a hyperautofluorescent ring and corresponding spectral-domain optical coherence tomography (SD-OCT) features seen in patients with autoimmune retinopathy.

METHODS

All eyes were evaluated by funduscopic examination, full-field electroretinography, fundus autofluorescence, and SD-OCT. Further confirmation of the diagnosis was obtained with immunoblot and immunohistochemistry testing of the patient's serum. Humphrey visual fields and microperimetry were also performed.

RESULTS

Funduscopic examination showed atrophic retinal pigment epithelium (RPE) associated with retinal artery narrowing but without pigment deposits. The scotopic and photopic full-field electroretinograms were nondetectable in three patients and showed a cone-rod pattern of dysfunction in one patient. Fundus autofluorescence revealed a hyperautofluorescent ring in the parafoveal region, and the corresponding SD-OCT demonstrated loss of the photoreceptor inner segment-outer segment junction with thinning of the outer nuclear layer from the region of the hyperautofluorescent ring toward the retinal periphery. The retinal layers were generally intact within the hyperautofluorescent ring, although the inner segment-outer segment junction was disrupted, and the outer nuclear layer and photoreceptor outer segment layer were thinned.

CONCLUSION

This case series revealed the structure of the hyperautofluorescent ring in autoimmune retinopathy using SD-OCT. Fundus autofluorescence and SD-OCT may aid in the diagnosis of autoimmune retinopathy and may serve as a tool to monitor its progression.

Outer retinal structure in patients with acute zonal occult outer retinopathy

PURPOSE

To correlate visual function with high-resolution images of retinal structure using adaptive optics scanning laser ophthalmoscopy (AOSLO) in 4 patients with acute zonal occult outer retinopathy (AZOOR).

DESIGN

Observational case series.

METHODS

Four women, aged 18 to 51, with acute focal loss of visual field or visual acuity, photopsia, and minimal funduscopic changes were studied with best-corrected visual acuity (BCVA), Goldmann kinetic and automated perimetry and fundus-guided microperimetry, full-field and multifocal electroretinography (ffERG and mfERG), spectral-domain optical coherence tomography (SD-OCT), and AOSLO imaging. Cone spacing was measured in 4 eyes and compared with 27 age-similar normal eyes. Additional functional testing in 1 patient suggested that cones were absent but rods remained. Serum from all patients was analyzed for anti-retinal antibody activity.

RESULTS

In all patients vision loss was initially progressive, then stable. Symptoms were unilateral in 2 and bilateral but asymmetric in 2 patients. In each patient, loss of retinal function correlated with structural changes in the outer retina. AOSLO showed focal cone loss in most patients, although in 1 patient with central vision loss such change was absent. In another patient, structural and functional analyses suggested that cones had degenerated but rods remained. Anti-retinal antibody activity against a ∼45 kd antigen was detected in 1 of the patients; the other 3 patients showed no evidence of abnormal anti-retinal antibodies.

CONCLUSIONS

Focal abnormalities of retinal structure correlated with vision loss in patients with AZOOR. High-resolution imaging can localize and demonstrate the extent of outer retinal abnormality in AZOOR patients.

Case of acute zonal occult outer retinopathy with abnormal pattern visual evoked potentials

Electrophysiological and morphological findings were studied in a case of acute zonal occult outer retinopathy (AZOOR) showing abnormal pattern visual evoked potentials (VEPs) at the onset and significant functional recovery in the natural course. A 21-year-old woman presented with acute onset of photopsia and a large scotoma in the right eye of 2 weeks duration. Her visual acuity was 20/20 in both eyes with no ophthalmoscopic and fluorescein angiographic abnormalities. However, a relative afferent pupillary defect and an enlarged blind spot were found in the right eye. The pattern VEPs were severely reduced when the right eye was stimulated. The amplitudes of both rod and cone full-field electroretinographics (ERGs) were reduced in the right eye. The amplitudes of the multifocal ERGs were reduced in the area of the enlarged blind spot. Irregularities in the inner segment/outer segment (IS/OS) line of the photoreceptors were observed over the nasal fovea by optical coherence tomography (OCT). The patient was followed without treatment. The enlarged blind spot disappeared in 3 months after the onset. At 5 months, reappearance of the IS/OS line was detected by OCT. At 6 months, the P₁₀₀ recovered to normal values. At 1 year, the reduced full-field ERGs were almost normal size and the multifocal ERGs in the area corresponding to the enlarged blind spot were also improved. ERG findings are crucial for differentiating AZOOR from retrobulbar neuritis, especially in patients with abnormal pattern VEPs. The pattern VEPs, full-field ERGs, multifocal ERGs, and OCT images can be abnormal in the early phase of AZOOR, but they can all improve during the natural course.

[Multiple evanescent white dot syndrome and multiple sclerosis]

PURPOSE

To describe a patient who fulfilled the criteria for both clinically definite multiple evanescent white dot syndrome (MEWDS) and multiple sclerosis.

METHODS

We performed a complete ophthalmologic and neurological examination in a 30-year-old woman who was referred to our department for blurred vision in her left eye (LE) with photopsia.

RESULTS

Following a complete ophthalmologic examination, the patient was diagnosed with MEWDS and coincident multiple sclerosis. She underwent therapy with intravenous methylprednisolone (1000 mg/day) for three days, followed by oral prednisone (1 mg/kg per day) for 15 days. Most of the symptoms and signs apparently regressed within one month, despite a still abnormal OCT macular scan, probably due to atrophic post-inflammatory changes in the outer and photoreceptor layers (rods and cones).

CONCLUSION

This report, showing the clinical features of MEWDS associated with multiple sclerosis, strongly suggests common neuropathological and inflammatory mechanisms between MS and white dot syndromes.

Patients with an acute zonal occult outer retinopathy-like illness rapidly improve with valacyclovir treatment

PURPOSE

To describe 3 cases of an acute zonal occult outer retinopathy-like illness responsive to valacyclovir hydrochloride.

DESIGN

Retrospective, interventional case series.

METHODS

Three patients were treated with valacyclovir and monitored by clinical examination, Goldmann visual field testing, and electroretinography.

RESULTS

Patients with an acute zonal occult outer retinopathy-like illness presented following progressive vision loss. This course was immediately reversed by treatment with oral valacyclovir, and visual acuity and visual field improved significantly at 1 week and 1 month. Patients remained stable without treatment during a follow-up period ranging from 1 to 3 years.

CONCLUSIONS

Some conditions with features of acute zonal occult outer retinopathy may be attributable to a subacute herpetic viral infection that is responsive to oral antiviral medication.

Fundus autofluorescence imaging of the white dot syndromes

OBJECTIVE

To characterize the fundus autofluorescence (FAF) findings in patients with white dot syndromes (WDSs).

METHODS

Patients with WDSs underwent ophthalmic examination, fundus photography, fluorescein angiography, and FAF imaging. Patients were categorized as having no, minimal, or predominant foveal hypoautofluorescence. The severity of visual impairment was then correlated with the degree of foveal hypoautofluorescence.

RESULTS

Fifty-five eyes of 28 patients with WDSs were evaluated. Visual acuities ranged from 20/12.5 to hand motions. Diagnoses included serpiginous choroidopathy (5 patients), birdshot retinochoroidopathy (10), multifocal choroiditis (8), relentless placoid chorioretinitis (1), presumed tuberculosis-associated serpiginouslike choroidopathy (1), acute posterior multifocal placoid pigment epitheliopathy (1), and acute zonal occult outer retinopathy (2). In active serpiginous choroidopathy, notable hyperautofluorescence in active disease distinguished it from the variegated FAF features of tuberculosis-associated serpiginouslike choroidopathy. The percentage of patients with visual acuity impairment of less than 20/40 differed among eyes with no, minimal, and predominant foveal hypoautofluorescence (P < .001). Patients with predominant foveal hypoautofluorescence demonstrated worse visual acuity than those with minimal or no foveal hypoautofluorescence (both P < .001).

CONCLUSIONS

Fundus autofluorescence imaging is useful in the evaluation of the WDS. Visual acuity impairment is correlated with foveal hypoautofluorescence. Further studies are needed to evaluate the precise role of FAF imaging in the WDSs.

Acute zonal occult outer retinopathy: a case report

BACKGROUND

Acute zonal occult outer retinopathy (AZOOR) is a disorder of unknown etiology with a predilection for young women. AZOOR is characterized by an acute loss of one or more zones of outer retinal function with a corresponding loss of visual field in one or both eyes. Patients present with photopsia, variable funduscopic changes, and abnormal electroretinogram (ERG) findings. There are no proven treatments. Diagnosed cases have a reasonable prognosis because central vision is often spared.

CASE REPORT

A 24-year-old white woman presented with acute photopsia with clouded temporal vision in the right eye (O.D.). Initial evaluation found a slightly swollen nerve fiber layer with no other outstanding lesions O.D. Over a 7-week follow-up period, there was significant progression into the deep chorioretinal tissues O.D. with an anterior chamber response. At 3 months, an afferent pupillary defect (APD) developed with significant retinal pigment epithelium (RPE) changes. After extensive testing, the consulting retinal specialist identified AZOOR as the etiology. At 21 and 31 months, the process remained in remission. Although primary symptoms subsided, the dense inferior-temporal field defect remained O.D.

CONCLUSION

AZOOR is a rare condition with subtle and often vague signs and symptoms making diagnosis difficult. The course of AZOOR, its clinical presentations, hypothesis of etiology, differential diagnosis, workup, management, and prognosis are reviewed.

Subconjunctivally implantable hydrogels with degradable and thermoresponsive properties for sustained release of insulin to the retina

The objective of this work is to develop subconjunctivally implantable, biodegradable hydrogels for sustained release of intact insulin to the retina to prevent and treat retinal neurovascular degeneration such as diabetic retinopathy. The hydrogels are synthesized by UV photopolymerization of N-isopropylacrylamide (NIPAAm) monomer and a dextran macromer containing multiple hydrolytically degradable oligolactate-(2-hydroxyetheyl methacrylate) units (Dex-lactateHEMA) in 25:75 (v:v) ethanol:water mixture solvent. Insulin is loaded into the hydrogels during the synthesis process with loading efficiency up to 98%. The hydrogels can release biologically active insulin in vitro for at least one week and the release kinetics can be modulated by varying the ratio between NIPAAm and Dex-lactateHEMA and altering the physical size of the hydrogels. The hydrogels are not toxic to R28 retinal neuron cells in culture medium with 100% cell viability. The hydrogels can be implanted under the conjunctiva without causing adverse effects to the retina based on hematoxylin and eosin stain, immunostaining for microglial cell activation, and electroretinography. These subconjunctivally implantable hydrogels have potential for long-term periocular delivery of insulin or other drugs to treat diabetic retinopathy and other retinal diseases.

Morphological study of acute zonal occult outer retinopathy (AZOOR) by multiplanar optical coherence tomography

PURPOSE

We set out to determine whether morphological retinal changes occur in patients with acute zonal occult outer retinopathy (AZOOR).

METHODS

Five patients diagnosed with AZOOR were studied. They included two men and three women, with an age range of 23-51 years. Symptoms and findings were retrospectively and prospectively collected. The three-dimensional multiplanar optical coherence tomography (OCT) Ophthalmoscope was used to examine the morphology of the retina in patients who were examined between April 2000 to December 2004. Standardized full-field electroretinograms (ERGs) and multifocal ERGs (mfERGs) were recorded.

RESULTS

All the patients reported an acute onset of visual disturbances including a decrease of central vision and photopsia. The a- and b-waves of full-field ERGs were decreased, and the mfERGs in the central area were reduced. Ophthalmoscopic examination showed no obvious fundus abnormalities. OCT Ophthalmoscopic images of a cross-sectional plane revealed hyporeflection at the level of the photoreceptor layer in the macular region in three of five patients, and presence of one or two layers in which the inner/outer segment junction of the photoreceptor layer was absent in the other two patients. En-face, constant depth C-scans, which present the image parallel to the retina, revealed an abnormal, patchy hyper-reflection in the affected eyes of two patients and in the non-affected eye in one of these two patients.

CONCLUSIONS

The changes in OCT Ophthalmoscope B-scan images indicate morphological damage to the photoreceptors, which probably accounts for the functional alterations. The alterations in the C-scan image in the normal fellow eye of one patient suggest that morphological changes may precede symptomatic changes.

Photoreceptor atrophy in acute zonal occult outer retinopathy

PURPOSE

To assess retinal morphology in acute zonal occult outer retinopathy (AZOOR) without ophthalmoscopically visible fundus changes.

METHODS

Retrospective case series. Two consecutive patients with bilateral AZOOR with photopsia corresponding to areas of visual field loss and a normal fundus appearance were examined using optical coherence tomography (OCT), automated perimetry and electroretinography (ERG).

RESULTS

Both patients demonstrated photoreceptor atrophy corresponding to partial or complete scotomata with reduced or extinct electroretinographic responses. Attenuation or complete loss of all the segments composing the photoreceptor layer was found by OCT. Full-field ERG revealed affection of the 30 Hz flicker responses and subnormal photopic responses in both patients and subnormal scotopic responses in case 1. Multifocal electroretinography (mERG) revealed localized outer retinal dysfunction. The field loss was more extensive than the area of photoreceptor loss.

CONCLUSION

Photoreceptor atrophy can be demonstrated in AZOOR without ophthalmoscopically visible fundus lesions.

Pathological findings of multifocal choroiditis with panuveitis and punctate inner choroidopathy

PURPOSE

To compare the pathological findings between multifocal choroiditis with panuveitis (MCP) and punctate inner choroidopathy (PIC).

METHODS

Fourteen eyes of 14 patients clinically diagnosed as having MCP or PIC who underwent surgical excision of choroidal neovascularization (CNV) were studied. Immunohistochemical findings of the excised CNV in MCP (eight eyes) and PIC (six eyes) cases were compared. Antibodies against vascular endothelial growth factor (VEGF), CD68, CD3, and CD20 were used as primary antibodies.

RESULTS

Expression of VEGF and CD68 in the CNV was observed in all MCF and PIC cases. In three of eight eyes with MCP, intraocular inflammatory findings were found clinically, while immunohistochemical study demonstrated infiltration of CD20-positive B lymphocytes in the CNV. No B lymphocyte infiltration was found in the six eyes with PIC. No differences in pathological findings were found between the five MCP eyes without intraocular inflammation and the six PIC eyes, with all eyes showing no B lymphocyte infiltration.

CONCLUSIONS

In MPC cases showing clinical inflammatory findings, infiltration of B lymphocytes was also observed histopathologically, suggesting that the presence of inflammatory cells in the anterior chamber or vitreous body clinically is an indicator of active inflammatory CNV. However, this study clarifies that MCP eyes without intraocular inflammation and PIC eyes are not different in histopathological findings.

Photoreceptor outer segment abnormalities as a cause of blind spot enlargement in acute zonal occult outer retinopathy-complex diseases

PURPOSE

To investigate the correlation between visual field (VF) defects in diseases of the acute zonal occult outer retinopathy (AZOOR)-complex and their spectral-domain optical coherence tomographic (OCT) findings.

DESIGN

Observational case series.

METHODS

Patients with AZOOR, multiple evanescent white dot syndrome (MEWDS), and multifocal choroiditis and panuveitis (MCP) examined in a private practice retinal referral center had threshold VF testing and spectral-domain OCT examination performed using a device capable of obtaining a block of 128 B-scans in a 6 x 6-mm region centered on the optic nerve and macula. The areas of defects in the boundary between the inner segments (IS) and the outer segments (OS) of the photoreceptors, termed the IS/OS boundary, were compared with the VF defects measured.

RESULTS

There were 18 evaluable eyes among one patient with MEWDS, two with AZOOR, and seven with MCP. In the 14 eyes with blind spot enlargement [corrected] corresponding IS/OS boundary defects were found in the [corrected] peripapillary region, while no IS/OS boundary defects were found in the four [corrected] eyes without blind spot enlargement. IS/OS boundary defects were seen over chorioretinal scars and areas of neovascularization and no widespread defects were seen [corrected] elsewhere in the fundus. The IS/OS boundary defects showed improvement, as did the blind spot enlargement, spontaneously in the patient with MEWDS and after treatment with immunosuppression in the patients with AZOOR.

CONCLUSION

The spectral-domain OCT finding of IS/OS boundary defects, implicating photoreceptor OS perturbation, appears to explain the blind spot enlargement in patients with AZOOR-complex diseases. These defects are not necessarily permanent.

Acute bilateral peripheral cone system dysfunction

PURPOSE

To report electrophysiological and psychophysical findings in an unusual case with acute loss of the peripheral visual field bilaterally.

METHODS

A 19-year-old woman underwent fundus photography, fluorescein angiography, visual field testing, determination of full-field electroretinograms (ERGs) and multifocal ERGs (mfERGs), and rod-cone perimetry in addition to routine ophthalmologic examinations.

RESULTS

Findings of fundus examination and fluorescein angiography were completely normal, and best-corrected visual acuity was 1.0 in both eyes. However, static perimetry revealed a temporal field defect in the right eye and an arcuate scotoma in the left eye. Full-field ERG cone responses were significantly reduced, but rod responses were normal in both eyes. Psychophysical rod-cone perimetry demonstrated that the peripheral cone system was impaired whereas the rod sensitivity was completely normal. mfERGs showed that the local cone responses were well preserved in the central retina but were severely reduced in the peripheral retina in both eyes.

CONCLUSIONS

These results indicate that there is an unusual retinopathy showing acute dysfunction of the peripheral cone system bilaterally whereas the rod system is functioning normally.

Fungal infection in patients with serpiginous choroiditis or acute zonal occult outer retinopathy

The etiologies of a number of retinopathies, including serpiginous choroiditis and acute zonal occult outer retinopathy (AZOOR), remain uncertain. Recently, we provided evidence that AZOOR is caused by Candida famata infection. The purpose of this article was to investigate the presence of fungal infection in five patients affected with serpiginous choroiditis and five patients with diagnosis of AZOOR. To assess the presence of fungal infection the presence of antibodies in human serum samples against C. famata, C. albicans, C. parapsilosis, C. glabrata and C. krusei was analyzed. In addition, quantitative PCR was carried out to detect fungal genomes in whole blood. Finally, the presence of fungal antigens in the serum samples of patients was investigated. Three AZOOR patients presented high antibody titers against Candida spp., while antibodies against Candida spp. were observed in serum samples from four patients with serpiginous choroiditis. Fungal genomes in peripheral blood were evidenced in serum samples from one AZOOR and four serpiginous choroiditis patients. Fungal antigens were also apparent in the serum of different patients. Our findings indicate that there was evidence of disseminated fungal infection in most patients examined.

Unilateral cone dysfunction as a manifestation of acute zonal occult outer retinopathy

PURPOSE

To report a patient with unilateral cone dysfunction (UCD) who later developed acute zonal occult outer retinopathy (AZOOR) in the contralateral eye.

METHODS

A 19-year-old Japanese woman was referred complaining of decreased vision and photopsia of the left eye. Static perimetry, full-field electroretinography (ERG), and multifocal ERGs (mfERGs) were performed to evaluate her visual functions. She returned 9 months later with visual field defect and photopsia in the right eye.

RESULTS

The static visual field of the left eye demonstrated a scotoma that extended from the physiologic blind spot to the center of the visual field. The cone full-field ERGs were extinguished with preservation of rod function. The mfERGs were reduced throughout the posterior pole of the left eye. The patient was diagnosed with UCD. She revisited us 9 months later complaining of visual symptoms in the right eye and was found to have an arcuate scotoma in the upper visual field corresponding to decreased mfERGs. These findings were consistent with clinical signs of AZOOR.

CONCLUSION

These findings indicate that UCD is one of the clinical manifestations of AZOOR.

Acute zonal occult outer retinopathy and multiple sclerosis

The case of a 30-year-old woman who had two episodes of photopsia along with sudden-onset monocular visual field defects, developing into bilateral tunnel vision within 4 years, is reported. She also had episodes of a right hemiparesis and right-sided hypoaesthesia, accompanied by severe fatigue. This patient fulfilled the criteria for both clinically definite multiple sclerosis and acute zonal occult outer retinopathy (AZOOR). AZOOR can have an onset with monocular visual field loss, and can be distinguished from optic neuritis. In addition, some observations suggest common neuropathological and inflammatory mechanisms between multiple sclerosis and AZOOR.

Safety in Nonhuman Primates of Ocular AAV2-RPE65, a Candidate Treatment for Blindness in Leber Congenital Amaurosis

Leber congenital amaurosis (LCA) is a molecularly heterogeneous disease group that leads to blindness. LCA caused by RPE65 mutations has been studied in animal models and vision has been restored by subretinal delivery of AAV-RPE65 vector. Human ocular gene transfer trials are being considered. Our safety studies of subretinal AAV-2/2.RPE65 in RPE65-mutant dogs showed evidence of modest photoreceptor loss in the injection region in some animals at higher vector doses. We now test the hypothesis that there can be vectorrelated toxicity to the normal monkey, with its human-like retina. Good Laboratory Practice safety studies following single intraocular injections of AAV-2/2.RPE65 in normal cynomolgus monkeys were performed for 1-week and 3-month durations. Systemic toxicity was not identified. Ocular-specific studies included clinical examinations, electroretinography, and retinal histopathology. Signs of ocular inflammation postinjection had almost disappeared by 1 week. At 3 months, electroretinography in vector-injected eyes was no different than in vehicle-injected control eyes or compared with presurgical recordings. Healed sites of retinal perforation from subretinal injections were noted clinically and by histopathology. Foveal architecture in subretinally injected eyes, vector or vehicle, could be abnormal. Morphometry of central retina showed no photoreceptor layer thickness abnormalities occurring in a dose-dependent manner. Vector sequences were present in the injected retina, vitreous, and optic nerve at 1 week but not consistently in the brain. At 3 months, there were no vector sequences in optic nerve and brain. The results allow for consideration of an upper range for no observed adverse effect level in future human trials of subretinal AAV-2/2.RPE65. The potential value of foveal treatment for LCA and other retinal degenerations warrants further research into how to achieve gene transfer without retinal injury from surgical detachment of the retina.

Isolation of Candida famata from a patient with acute zonal occult outer retinopathy

The etiology of a number of retinopathies, such as acute zonal occult outer retinopathy (AZOOR), remains undetermined. Candida famata was isolated from conjunctival exudates of a patient diagnosed with AZOOR. This yeast was very abundant, particularly in the more affected eye, while no other pathogens or fungal species were in evidence. Immunological tests revealed the presence of antigen-specific T lymphocytes by using C. famata as a challenge. Moreover, enzyme-linked immunosorbent assay analysis showed the presence of specific antibodies against this yeast in the patient's blood. Delayed hypersensitivity by use of a skin test was also positive. Finally, antifungal treatments led to improvements in several clinical symptoms, including funduscopic analysis. However, despite prolonged treatment with fluconazole and itraconazole, C. famata still appeared in the conjunctival exudates. The new antifungal voriconazole may represent a better choice for treatment.