The aim of this retrospective study was to evaluate the inner retinal changes in patients with ABCA4-related retinal dystrophy (ABCA4-RD), and correlate these changes with the photopic negative response (PhNR), a cone ERG component reflecting inner retinal activity, previously reported as altered in ABCA4-RD. Nineteen ABCA4-RD patients (21 eyes) and 20 age-matched controls (20 eyes) were included in the study. A detailed ophthalmological examination, a spectral domain optical coherence tomography with volumetric segmentation of retinal layers, as well as electrophysiological recordings of the ERG PhNR, were obtained in all patients and controls. The patient data were compared individually with normal values (mean and 95% confidence limits) and evaluated by Pearson's and linear correlation analyses. The spectral domain optical coherence tomography examination showed in the perifoveal retina a laminopathy with thinning (<95% normal confidence limits) of the outer nuclear (18/21 eyes) and the ganglion cell layer (11/21 eyes), and relative sparing or slight thickening of the inner nuclear layer. The PhNR amplitude was reduced (<95% normal confidence limits) in 20 of the 21 study eyes. In the same eyes, PhNR losses were always greater than the cone b-wave amplitude losses. The ganglion cell layer volume was positively correlated with the PhNR amplitude (r = 0.69; P < 0.01). The present results show in ABCA4-RD patients a correlation of inner retinal anatomical changes with corresponding functional abnormalities, as detected by the PhNR. These findings may be interpreted as a causal relationship between anatomical and functional changes in the inner retina. Longitudinal studies on the natural history of ABCA4-RD should consider the role of inner retina both on the disease progression and the efficacy of treatments selectively focused on restoring the ABCA4 function and the photoreceptors' health.

To evaluate adult-onset neuronal intranuclear inclusion disease (NIID)-related retinopathy with guanine-guanine-cytosine repeat expansions in NOTCH2NLC. Neuro-ophthalmic evaluations, including best-corrected visual acuity, slit-lamp biomicroscopy, intraocular pressure (IOP), ultrasound biomicroscopy, pupillometry, fundus photography, fundus autofluorescence (FAF), optical coherence tomography (OCT), Humphrey visual field, full-field electroretinography (ERG), and multifocal ERG (mf-ERG) were performed in patients with gene-proven NIID. Nine patients (18 eyes) were evaluated, with a median age of 62 years (55-68) and only one man was included in our study. Six patients presented with decreased visual acuity or night blindness, whereas the other three were asymptomatic. The visual acuity was measured from 20/200 to 20/20. Miosis was present in eight patients, four of whom had ciliary process hypertrophy and pronation, and three of whom had shallow anterior chambers. Fundus photography, FAF, and OCT showed consistent structural abnormalities mainly started from peripapillary areas and localized in the outer layer of photoreceptors and inner ganglion cell layer. ERG and mf-ERG also revealed retinal dysfunction in the corresponding regions. Patients with NIID showed both structural and functional retinopathies which were unique and different from common cone-rod dystrophy or retinitis pigmentosa. Patients with miosis may have a potential risk of an angle-closure glaucoma attack. Neuro-ophthalmic evaluations is essential for evaluating patients with NIID, even without visual symptom.

To investigate the prevalence and features of cystoid spaces (CS) in patients with confirmed genetic diagnosis of choroideremia (CHM) using swept source optical coherence tomography (OCT). We retrospectively reviewed CHM patients examined at the Regional Reference Center for Hereditary Retinal Degenerations at the Eye Clinic in Florence. We took into consideration genetically confirmed CHM patients with ophthalmological and swept source optical coherence tomography (OCT) examinations. The presence/absence and location of cystoid spaces in the retina of each eye were reported. A total of 42 eyes of 21 CHM patients were included in our series. The average age of the patients was 36.5 ± 20.1 (range, 13-73 years). The average best-corrected visual acuity (BCVA) for all patients was 0.63 ± 1.00 logMar (range, 0-2,80). CS were present in 15 eyes of eight patients (8/21, 38%). In all cases, CS were located in inner nuclear layer (INL); in five eyes of three patients, CS were detected also in ganglion cell layer (GCL). CS appeared as microcistoyd abnormalities and were detected in retinal areas characterized by retinal pigment epithelium (RPE) and outer retinal layers atrophy at the transition zone. Cystoid spaces in choroideremia showed peculiar features; they are clusters of small-size extrafoveal degenerative cysts mainly located in inner nuclear layer at the transition zone where outer retinal layers and RPE are severely damaged.