Temporal Retinal Nerve Fiber Loss in Patients with Spinocerebellar Ataxia Type 1

Abstract

BackgroundAutosomal dominant spinocerebellar ataxia type 1 is an adult onset progressive disorder with well characterized neurodegeneration in the cerebellum and brainstem. Beyond brain atrophy, few data exist concerning retinal and optic nerve involvement.Objective To evaluate retinal changes in SCA1 patients compared to age and gender matched healthy controls.Methodology/Principal FindingsNine patients with SCA1 were prospectively recruited from the ataxia clinic and were compared to nine age and gender matched healthy controls. Both cohorts received assessment of visually evoked potentials and eye examination by optical coherence tomography to determine retinal nerve fiber layer thickness and total macular volume. While no differences were found in visually evoked potentials, SCA1 patients showed a significant reduction of mean retinal nerve fiber layer thickness (RNFLT) compared to healthy controls (84±13 µm vs. 97±8 µm, p = 0.004). Temporal areas showed the most prominent RNFLT reduction with high statistical significances (temporal-inferior: p<0.001, temporal: p<0.001, temporal-superior: p = 0.005) whereas RNFLT in nasal areas was in the range of the control group. From six SCA1 patients an additional macular scan was obtained. The comparison to the corresponding healthy control showed a slight but not significant reduction in TMV (8.22±0.68 mm3 vs. 8.61±0.41 mm3, p = 0.15).ConclusionIn SCA1 patients, we found evidence for degeneration of retinal nerve fibers. The temporal focus of the observed retinal nerve fiber layer reduction suggests an involvement of the papillo-macular bundle which resembles pathology found in toxic or mitochondrial optic nerve disease such as Leber's hereditary optic neuropathy (LHON) or dominant optic atrophy (DOA).

Optic coherence tomography shows inflammation and degeneration in major depressive disorder patients correlated with disease severity

“…This finding supports volumetric MRI studies that found decreased gray matter in brains of MDD patients (Bora et al, 2012). This finding is also consistent with previous OCT studies that found decreased GCL and IPL volumes in neurodegenerative diseases such as multiple sclerosis (Saidha et al, 2011), spinocerebellar ataxia (Stricker et al, 2011), and Parkinson's disease (Roth et al, 2014). We found significantly lower GCL and IPL volumes in recurrent MDD patients than first episode patients.…”

Optical coherence tomography findings in spinocerebellar ataxia-3

“…For instance, RNFL thinning observed in our study showed predominance for the superior and inferior sectors, which could mimic glaucomatous optic disc neuropathy, thus an exhaustive ophthalmologic examination, including intraocular pressure measurement and visual field testing, should be performed in these patients. In that sense, our results differ substantially of the ones published by Stricker et al, 8 who reported a temporal fibre affection in SCA-1, resembling pathology found in toxic or mitochondrial optic nerve diseases. Thus, the physiopathology of the neuro-opthalmologic degeneration in SCA-3 seems to be more similar to the observed in Alzheimer's and Parkinson's disease rather than in the SCA-1 and toxic or mitochondrial optic nerve diseases.…”

Optic Disc and Retinal Nerve Fibre Layer Changes in Parkinson’s Disease

“…Loss of the temporal RNFL was documented in mitochondrial optic neuropathies such as Leber hereditary optic neuropathy or dominant optic atrophy; and a mitochondrial pattern has also been proposed for PD. 10,12,13 Temporal RNFL thinning was also reported in autosomal recessive cone-rod dystrophy, spinocerebellar ataxia type 1 and multiple sclerosis. 12,14,15 Other than a mitochondrial pattern, localised breakdown of oxidative defence mechanisms and sensitivity of the temporal RNFL to early damage and subclinical disease activity were also suggested.…”

“…10,12,13 Temporal RNFL thinning was also reported in autosomal recessive cone-rod dystrophy, spinocerebellar ataxia type 1 and multiple sclerosis. 12,14,15 Other than a mitochondrial pattern, localised breakdown of oxidative defence mechanisms and sensitivity of the temporal RNFL to early damage and subclinical disease activity were also suggested. 12,15 More evidence is needed to understand the mechanism of sectoral thinning of the RNFL.…”

“…12,14,15 Other than a mitochondrial pattern, localised breakdown of oxidative defence mechanisms and sensitivity of the temporal RNFL to early damage and subclinical disease activity were also suggested. 12,15 More evidence is needed to understand the mechanism of sectoral thinning of the RNFL.…”