Clinical features of focal choroidal excavation subtypes and their association with choroidal neovascularization.

Abstract

Background: This study aimed to propose a new classification of focal choroidal excavation (FCE), summarize the clinical and multimodal imaging characteristics of FCE subtypes, and explore the relationship between FCE and choroidal neovascularization (CNV).

Methods: In this retrospective observational study, patients diagnosed with FCE using spectral-domain optical coherence tomography (SD-OCT) were included. FCE was classified according to associated retinochoroidal diseases. Clinical and multimodal imaging features, as well as the association of CNV, were investigated for different subtypes of FCE.

Results: The study included 105 eyes with FCE from 93 Chinese patients, with a mean age of 41.66 years (range: 15-75 years). Among the 93 eyes with comprehensive multimodal imaging data, FCE subtypes were classified as retractive (34.41%), inflammatory (18.28%), pachychoroidal (23.66%), atrophic (9.68%), and idiopathic (13.97%). Idiopathic FCE patients had significantly better best-corrected visual acuity compared to those with retinochoroidal disease-associated FCE (P<0.001). Inflammatory FCE was associated with higher myopia (median refractive error: -6.00 D, P<0.001) and reduced choroidal thickness (P=0.014), whereas pachychoroidal FCE showed increased choroidal thickness. Retractive FCE exhibited the highest CNV rate at baseline (P<0.001), with CNV more likely in larger greatest linear dimension (GLD) (P=0.004) and female patients (P=0.016). Although CNV was present in 50.54% of cases at baseline, it grew within FCE during follow-up in only 8.60% of cases, and 9.68% experienced CNV recurrence.

Conclusion: Different FCE subtypes exhibit distinct clinical features. Idiopathic FCEs are generally stable, while the emergence of secondary CNV is linked to anatomical alterations caused by FCE and associated retinochoroidal diseases.