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

[Objective] To observe the clinical features of acute zonal occult outer retinopathy (AZOOR).[Methods] Eighteen patients (18 eyes) with AZOOR were enrolled in this study.All the patients were examined for corrected visual acuity,fundus examination,visual field and electroretinography (ERG).For part of these patients,fluorescein angiography (FFA),optic coherence tomography (OCT),visual evoked potential (VEP) and multifocal ERG (mf-ERG) were performed.Clinical features wereobserved.Comparative analysis was performed on the electrophysiological Results between affected eyes and fellow eyes.The consistency of OCT,visual field and mf-ERG results was investigated.[Results]The patients included three males and 15 females.All patients were unilateral involved.16 eyes (88.9％) were myopia,two eyes (11.1％) were emmetropia.11 eyes (61.1％) have normal fundus; single yellow-white punctuate lesion or old RPE lesion near macular were found in three eyes (16.7％) ; depigmented zones in temporal retina were found in four eyes (22.2％).All central visual field results were abnormal,but peripheral visual field results were normal.OCT findings included irregularity,absence or breaks of the photoreceptor inner segment/outer segment (IS/OS) junction.Amplitudes of full-field ERG were reduced in the affected eyes (t=3.516,2.689,3.103,3.517,2.999,3.309;P＜0.05),and implicit times were delayedin most responses except for rod response (t1=1.023,P=0.306).Amplitudes of P100 wave of visual evoked potential were reduced statistically (t=2.04,P=0.041),but the differences of implicit times between the affected eyes and the fellow eyes were not statistically significant (t =1.687,P =0.092).Amplitude reduction of multifocal ERG existed in all affected eyes.Coincidence was found between results of OCT and mf-ERG.But abnormal zones found by central visual field did not always coincide with those by mf-ERG.[Conclusion]s The majority of patients who develop AZOOR are young women with myopia.Most patients have normal fundus.Central visual field and electrophysiological examinations are always abnormal.Irregularity,absence or breaks of the photoreceptor 1S/OS junction can be proved by OCT. Key words: Retinal diseases/ diagnosis; Electroretinography/utilization; Tomography, optical coherence/utilization

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. Six eyes of 5 female patients diagnosed with AZOOR were followed up for 4months 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. 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. 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.

Visual evoked potentials (VEPs) were recorded of 60 infants and children with cerebral blindness, aged between six weeks and 10 years, and compared with age-matched normative data. Every patient had abnormal VEPs. 18 had absent flash and pattern VEPs and 13 had atypical or atypical and asymmetrical flash and pattern VEPs. Of the remaining 29, most had greater abnormality of pattern than of flash VEPs and greater abnormalities over parietal and temporal than occipital areas. Eight patients had normal occipital responses to flash and five others had delayed responses with normal morphology. One had normal occipital responses to pattern stimuli. All of these had abnormal late occipital responses or abnormal responses over the parietal and temporal areas. It is recommended that visual assessments using VEPs employ both flash and pattern stimuli, that pre-occipital as well as occipital recordings be made and that tracings be compared with age-specific normative data.

Genetic Rescue Reverses Microglial Activation in Preclinical Models of Retinitis Pigmentosa.

Case of acute zonal occult outer retinopathy resembling retrobulbar optic neuropathy

Purpose: To evaluate peripapillary acute zonal occult outer retinopathy in a 67-year-old man. Methods: Images were obtained using fundus photography, fluorescein angiography (FA) and indocyanine green angiography (ICGA), fundus autofluorescence (FAF) imaging, and optical coherence tomography (OCT). Visual field testing and multifocal electroretinogram (mfERG) were also performed to evaluate retinal function. Results: Fundus photographs showed subtle pigmentary changes in the peripapillary region, while FAF imaging showed clearly defined hypofluorescent areas in the peripapillary region. Intense hyperfluorescent lesions were also seen underneath hypofluorescent areas. A transmission defect with a granular hyperfluorescence was visible on FA, and ICGA showed hypofluorescence within the lesion. The outer border of the peripapillary zone appeared to block the underlying choroidal fluorescence. The photoreceptor inner segment/outer segment line was absent on OCT images from this area in both eyes, and hyperreflective punctate drusen-like materials were present at the outer border of the peripapillary zone. Visual field testing by Goldmann perimetry showed blind-spot enlargement, and mfERG showed corresponding amplitude reductions. Conclusions: We speculate that the intense hyperautofluorescent material at the outer border of the peripapillary zone might be accumulated drusenoid lipofuscin.

Dear editor, We read with great interest the article entitled BSpectraldomain optical coherence tomography imaging of mucopolysaccharidoses I, II, and VI A^ by Seok et al. [1]. Although the study provides important data, we have several comments. First, there is a typing error in the title. It should be B...mucopolysaccharidoses I, II, and IVA^ instead of BVI A^. Second, as for mucopolysaccharidoses (MPS) type VI, we do have some spectral-domain optical coherence tomography (SD-OCT) images of MPS type VI, which show depigmented retinopathy and thinning of the choroid [2]. Third, thinning of the choroid might play a role in the development of pigmentary retinopathy in MPS I, II, and VI, and we suggested that the SD-OCT with enhanced depth imaging might help evaluate the chorioretinopathy of MPS patients [2]. Fourth, Seok et al. described cystoid macular edema in case 7 (MPS II). We also observed prominent cystic spaces in the inner nuclear layer and outer nuclear layer of a MPS II patient, but those cystic spaces extend far beyond macular area (beyond 6,000 μm diameter). The character of the contents of the cystic spaces is still unknown and needs further study. However, those cystic spaces resolved with time in our patient, who did not receive enzyme replacement therapy. No loss of ellipsoid zone was noted 3 years after resolution of those cystic spaces. Therefore, those cystic spaces or fluid accumulation might not be directly related to the loss of ellipsoid zone or degeneration of photoreceptor cells. Fifth, their study showed central foveal external limiting membrane (ELM) thickening and inner segment/outer segment (IS/OS) thinning in MPS I and II. The ages of their patients were between 9 and 20. We also observed thickened ELM in the central foveal area and loss of ellipsoid zone in the extrafoveal area. The thickened ELM at central foveal area was noted in MPS I and MPS II, but not so evident in MPS VI. The ELM is formed by the attachment site of the Muller cells and the adjacent photoreceptor cells. It is possible that accumulation of mucopolysaccharides might lead to the activation of the Muller cells and hence thickened ELM [2]. Although IS/OS thinning at fovea was demonstrated in their study, IS/OS thinning wasmoremarked in the perifoveal (case 6, 7, 8, 10, and 11) and parafoveal areas (case 10). In our study, loss of ellipsoid zone was mainly noted in extra foveal area, and the remaining ellipsoid zone became smaller with advancing age. In two of our MPS II patients, aged 46 and 49 years old respectively, the fundus examination revealed pigmentary retinopathy mimicking retinitis pigmentosa. The SDOCT showed that the ellipsoid zone existed only in the very central fovea. However, both patients still kept a visual acuity of 20/40 in each eye and intact color discrimination. Therefore, whether rod cells are involved more than cone cells and the significance of IS/OS thinning at fovea need further investigation. Lastly, in their study, five eyes of three MPS IVA patients showed normal OCT results. Our study also demonstrated similar results in 16 eyes of eight MPS IVA patients. * Yuan-Chieh Lee yuanchieh.lee@gmail.com

In kidney transplant recipients (KTRs), uraemia-induced central nervous system damage partly subsides, while the long-lasting exposure to tacrolimus may cause pathologic visual evoked potentials (VEP) findings, which have not been investigated yet. Thus, the aim of the present study was to assess the effect of tacrolimus maintenance treatment on bioelectrical function of optic nerves in stable KTRs. Sixty-five stable KTRs were enrolled, including 30 patients treated with twice-daily (Prograf) and 35 patients treated with prolonged once-daily (Advagraf) tacrolimus formulation. In all patients, pattern and flash VEP measurements were performed. Tacrolimus dosing and exposure were also analyzed. Overall, 129 eyes were analyzed. In pattern VEP, both (1°) and (15′) latencies of P100 waves were significantly longer, whereas (1°) and (15′) amplitudes were lower in the Advagraf group as compared with the Prograf group. Multivariate regression analyses revealed that the use of Advagraf (vs. Prograf) was independently associated with longer (1°) and (15′) P100 latencies and lower corresponding amplitudes, whereas log tacrolimus daily dose was only related to amplitudes in a whole study group. In flash VEP, log tacrolimus trough level was associated with negative changes in P2 wave amplitude irrespective of tacrolimus formulation, whereas its association with P2 latency was observed only in the Prograf group. Both the type of tacrolimus formulation and drug exposure influenced the VEP parameters in stable KTRs.

Resident Perspectives 56-5

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

OCT Interpretations

To assess retinal morphology in acute zonal occult outer retinopathy (AZOOR) without ophthalmoscopically visible fundus changes. 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). 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. Photoreceptor atrophy can be demonstrated in AZOOR without ophthalmoscopically visible fundus lesions.

Macular Function and Morphologic Features in Juvenile Stargardt Disease: Longitudinal Study

Macular Edema in Premature Infants

Purpose. To characterize the optical coherence tomography (OCT) findings in late-stage Vogt-Koyanagi-Harada (VKH) disease and its correlation with visual function. Methods. The records of patients with late-stage VKH disease (defined as ≥12 months from disease onset) were retrospectively reviewed. The analysis focused on the OCT findings and microperimetry, in addition to the possible correlation between morphology and functional findings. Results. Twenty-nine patients (58 eyes) were included. Mean age at onset was 34.24 ± 10.67 years. The OCT revealed that the outer retina and retinal pigment epithelium (RPE) were mainly affected. These effects included RPE thickening and breakage or disappearance of the cone outer segment tip (COST) line and/or inner segment/outer segment (IS/OS) junction. The COST line and IS/OS results were related to macular function and the interval between symptom onset and initiation of high-dose corticosteroid treatment (all P < 0.01). Eyes with intact COST lines demonstrated intact IS/OS and normal RPE layers as well as better visual function and normal retinal sensitivity. Conclusions. The OCT findings are strongly correlated with macular function, as well as other clinical findings in late-stage VKH. With respect to the COST line and retinal sensitivity especially, the OCT and microperimetry findings may be useful for evaluating later-stage VKH.