Prechoroidal cleft in neovascular age-related macular degeneration (AMD): A narrative review of pathophysiology, clinical implications and prognosis.

The prechoroidal cleft (PC) is a hyporeflective space visualized on optical coherence tomography (OCT), typically located within the pigment epithelial detachments (PEDs) in neovascular age-related macular degeneration (nAMD). Although its pathogenesis is not yet fully understood, proposed mechanisms include fluid accumulation secondary to macular neovascularization (MNV), contractile forces from fibrovascular tissue and chronic structural remodelling of the outer retinal layers. This narrative review synthesizes the current evidence regarding the imaging features, pathophysiological mechanisms, clinical relevance and prognostic implications of the PC in nAMD. The presence of a PC has been variably associated with MNV activity, poor visual outcomes, increased treatment burden and a higher risk of complications, such as retinal pigment epithelium (RPE) tears and submacular haemorrhage (SMH). However, emerging data suggest that the cleft may regress following sustained anti-VEGF therapy, implying a potential role as a marker of therapeutic response and anatomical improvement. Thus, the PC may serve as a dynamic biomarker of disease activity in nAMD patients. Nevertheless, its precise role in disease progression remains unclear, highlighting the need for further longitudinal and histopathological studies.