Spectral domain optical coherence tomography findings in eyes with acute ischaemic retinal whitening

Abstract

Acute retinal ischaemia presents in various forms depending on the type and location of the associated vascular occlusion. Cotton wool spots have been considered one manifestation of ischaemia and represent swelling in the nerve fibre layer. However, clinical retinal whitening also occurs in areas not affected by cotton wool spots, and has distinguishing spectral domain optical coherence tomography (SD-OCT) features. We present SD-OCT findings of hyper-reflectivity and thickening in four eyes with representative retinal arterial or retinal venous occlusions, specifically branch retinal artery occlusion, central retinal vein occlusion, Purtscher-like retinopathy and ophthalmic artery occlusion. The spectrum of retinal ischaemia from various causes was found to manifest in inner nuclear layer hyper-reflectivity and thickening on SD-OCT. En Face OCT imaging further characterises the topographical distribution of ischaemia, and reveals patterns which provide insight into the pathological processes involved.

Evidence for an enduring ischaemic penumbra following central retinal artery occlusion, with implications for fibrinolytic therapy

“…These plaques alternate with blocks of normal INL reflectivity related to the macular arteries in a segmented pattern (Figs. 12 and 14) (Coady et al, 2014). The OCT signs are in keeping with the proposed pathophysiology of peri-venous opacification, the transparent segments comprising both normoxic and hypoxic micro-compartments (Subsection 3.3.)…”

“…The true picture was to emerge from the OCT findings in hypoperfusion maculopathy complicating CRVO where ischaemic opacification was shown to be confined to the middle retina (Sarda et al, 2011). As is also evident in "partial" CRAO and carotid stenosis (Coady et al, 2014), the inner retina is minimally thickend overall by the localised infarction (apart, that is, from the focal NFL expansions representing cotton-wool spots), and the retina's layered internal structure remains readily discernible (Fig. 12).…”

Cotton Wool Spots after Anti-Vascular Endothelial Growth Factor Therapy for Macular Edema Associated with Central Retinal Vein Occlusion

“…Retinal whitening is reported to be produced by a focal circulatory disturbance of the small retinal arterioles [31,32,33]. It is seen as a hyperreflective lesion mainly in the retinal nerve fiber layer or inner plexiform layer on OCT sections [33].…”

Purtscher’s retinopathy – case report and literature review

“…On the SD-OCT image, cotton wool spots appear as hyperreflective areas in the inner layers of the retina [16]. Purtscher flecken on an SD-OCT scan correspond to increased reflectivity of the intranuclear layer (INL) [17]. In the presented case, the SD-OCT also revealed hyperreflective inner retinal layers, including the INL (Figure 3).…”