Reversing the paradigm on the urgency of acute retinal detachments defined by their foveal status: when off may be more urgent than on

Abstract

The visual prognosis is good for what is generally termed ‘macula-on’ rhegmatogenous retinal detachments (RRDs) but often less favourable for ‘macula-off’ RRDs. The longer the fovea is detached and the higher the detachment is from the retinal pigment epithelium, the worse the visual outcome.1–5 Indeed, it is the exquisitely engineered fovea that is the key determinant of good visual recovery, and as such, we need to be more precise with the terminology and replace the traditional terms of ‘macula-on/off’ with ‘fovea-on/off’.6 While posturing and/or immobility induced by bilateral eye patching may temporarily reduce or prevent the spread of subretinal fluid (SRF) under the fovea prior to surgery,7–11 prompt surgical intervention is key for improving visual outcomes. As soon as retinal detachment occurs, inflammatory and wound healing changes start. In animal models, photoreceptor apoptosis has been shown to occur as early as 12 hours after retinal detachment, followed by extensive remodelling with functional and morphological changes eventually involving all retinal layers. Photoreceptor outer segments progressively degenerate, inner segments reorganise, rod and cone opsins are redistributed, and rod axons retract while cones undergo changes in shape.12 The longer the retina remains detached, the more extensive these changes become and the less likely there is to be complete or near complete recovery of visual function following surgical repair. Furthermore, the damage to cellular functions in fovea-off RRDs also affect other qualities of vision besides acuity, including contrast sensitivity, colour vision and stereopsis.13 14 Although the exact relationships between these RRD-induced changes in retinal anatomy and recoverable function are unclear, they appear to be time critical, with irrecoverable loss occurring within 24 hours. Studies analysing the effect of the duration of loss of central vision (LCV) prior to surgery have shown a deleterious effect of duration on postoperative visual …