title: Retinal involvement in amyotrophic lateral sclerosis: a study with optical coherence tomography and diffusion tensor imaging.
abstract: Although motor neuron degeneration is the predominant feature in ALS, recent data point to a more widespread pathology also comprising non-motor symptoms. Retinal thinning has been reported in a variety of neurodegenerative conditions. Yet, studies of retinal involvement in ALS are sparse and results are heterogeneous. We studied retinal alterations in ALS using a systematic approach combining Optical Coherence Tomography (OCT), Diffusion Tensor Imaging (DTI) and clinical phenotyping. We hypothesized that selective changes of specific retinal layers may be a reflection of overall neurodegeneration as measured by DTI. Spectral domain OCT images were analyzed to calculate the average thickness of retinal layers in 71 ALS patients and 20 controls. In 30 patients, the region of interest (ROI) based fractional anisotrophy (FA) was measured in the corticospinal tract (CST), as this region is preferentially affected by motor neuron degeneration. Clinical data were collected for correlation analysis. Patients showed a significant thinning of the inner nuclear layer (INL; p = 0.04) and the retinal nerve fibre layer (RNFL; p = 0.004) compared to controls. We saw significant correlations between retinal thickness and FA values of the CST in patients (p = 0.005). No significant correlation between clinical parameters and retinal involvement was observed. Our study provides evidence for a retinal involvement in ALS. Interestingly, ALS patients show a reduction in FA of the CST, which is correlated to retinal thinning. We conclude that retinal involvement is in fact associated to overall neurodegeneration and may be regarded as a potential technical biomarker in ALS.
authors.affiliation: Department of Neurology, Ulm University, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: Annemarie
authors.initials: A
authors.lastname: Hübers
authors.affiliation: Department of Neurology, Ulm University, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: Hans Peter
authors.initials: HP
authors.lastname: Müller
authors.affiliation: Institute of Epidemiology and Medical Biometry, Ulm University, Schwabstraße 13, 89075, Ulm, Germany.
authors.forename: Jens
authors.initials: J
authors.lastname: Dreyhaupt
authors.affiliation: Department of Neurology, Ulm University, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: Kathrin
authors.initials: K
authors.lastname: Böhm
authors.affiliation: Department of Neurology, Ulm University, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: Florian
authors.initials: F
authors.lastname: Lauda
authors.affiliation: Department of Neurology, Ulm University, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: Hayrettin
authors.initials: H
authors.lastname: Tumani
authors.affiliation: Department of Neurology, Ulm University, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: Jan
authors.initials: J
authors.lastname: Kassubek
authors.affiliation: Department of Neurology, Ulm University, Oberer Eselsberg 45, 89081, Ulm, Germany.
authors.forename: Albert C
authors.initials: AC
authors.lastname: Ludolph
authors.affiliation: Department of Neurology, Ulm University, Oberer Eselsberg 45, 89081, Ulm, Germany. elmar.pinkhardt@uni-ulm.de.
authors.forename: Elmar H
authors.initials: EH
authors.lastname: Pinkhardt
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000690:Amyotrophic Lateral Sclerosis / Q000473:pathology*; D056324:Diffusion Tensor Imaging; D005260:Female; D006801:Humans; D007090:Image Interpretation, Computer-Assisted; D008297:Male; D008875:Middle Aged; D012160:Retina / Q000473:pathology*; D041623:Tomography, Optical Coherence
keywords: Amyotrophic lateral sclerosis; Neurodegeneration; Optical coherence tomography; Retina; Technical biomarker