Spectral Domain Optical Coherence Tomography (SD-OCT) Findings in Refsumʼs Disease

Introduction

Refsumʼs disease (OMIM 266500) is a very rare (about 60 cases have been reported worldwide) autosomal recessive inherited peroxisomal error of lipid metabolism with impaired alpha-oxidation of branched fatty acids that leads to an accumulation of phytanic acid in tissues and plasma [1]. Various mutations of genes like PEX7 (encodes PTS2 receptor) or PHYH (encodes phytanoyl-CoA hydroxylase) are associated with Refsumʼs disease. Most cases are detected by the clinical manifestations in the early childhood. Typical clinical signs are retinitis pigmentosa, cerebellar ataxia and peripheral neuropathy. Other symptoms are acustic nerve deafness, cardiomyopathy, cutaneous ichthyosis, and epiphysial dysplasia [2], [3]. Patients with Refsumʼs disease can effectively be treated by phytanic acid-restricted diet or plasmapheresis. With reduction of phytanic acid levels developmental progression of neurological signs can be slowed or prevented. Monitoring of the treatment effect is possible in the short term by the quantification of serum phytanic acid [4]. Besides the general clinical development, objective and easy-to-apply methods for the evaluation of long-term treatment effects are not established. SD-OCT follow-up may be capable to provide such a long-term treatment control. So far no description of SD-OCT findings in patients with Refsumʼs disease is available in literature.

^* Both authors contributed equally to this publication.

• Reference

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