Directional OCT Scans of the Macula Reveal Henle Fibre Layer-Related Imaging Patterns

Introduction

Optical coherence tomography (OCT) has become an invaluable tool in ophthalmic decision making, driven in large part by the onset of modern intravitreal pharmacotherapies [1]. There are several artifacts potentially involved in the interpretation process of OCT scans, most of these are influenced by image quality [2] and the underlying retinal pathology itself [3]. A special type of artifact is the appearance of the typically hyperreflective Henle Fiber Layer (HFL) as a part of the outer nuclear layer (ONL) under specific imaging conditions [4], [5]. This artifact can be erroneously interpreted as a pathological structural alteration while it constitutes no retinal pathology. The appearance of the HFL is dependent on the imaging beam entrance at the pupil and the resultant oblique scanning of the macula. By changing the orientation of light incident on the retina, directional OCT (D-OCT) adds optical contrast to directionally reflective structures, visualizing the HFL [5].

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