Correlations between OCT, OCT angiography and fundus autofluorescence in adults with superficial optic disc drusen: The importance of multimodal imaging.

Abstract

Background: Optic nerve head drusen (ONHD) are benign calcified deposits that can compress local capillaries, disrupt blood flow and potentially lead to visual loss.

Objectives: The aim of the study was to present the correlations between optical coherence tomography (OCT), OCT angiography (OCTA) results and fundus autofluorescence (FAF) findings in patients with ONHD, and to highlight the importance of multimodal imaging in the diagnosis and management of this pathology.

Material and methods: This retrospective study included 21 patients (36 eyes) with ONHD, with a mean age of 45.75 years (range: 19-71 years), who had no other ocular pathologies. All participants underwent a full ophthalmic examination and multimodal imaging using the DRI Triton OCT (Topcon). Drusen presence was divided into quadrants based on FAF and correlated with OCT and OCTA results.

Results: Optic nerve head drusen were unilateral in 6 patients (28.57%) and bilateral in 15 (71.43%). Drusen were most common in the nasal and superior quadrants (NQ and SQ) but were significantly more frequent in the inferior (IQ) and temporal (TQ) quadrants in patients with bilateral ONHD. Eyes with drusen located in the IQ and TQ showed a significantly decreased radial peripapillary capillary (RPCP) vessel density (VD). Retinal nerve fibre layer (RNFL) measurements showed the strongest positive correlations with RPCP, especially in the IQ (r = 0.78, p < 0.001). Ganglion cell layer and nerve fiber layer (GCL++) thickness showed significant correlations with RPCP VD, particularly in the IQ and TQ (p < 0.001 for both).

Conclusions: Fundus autofluorescence is a valuable tool for identifying superficial drusen. Optical coherence tomography and OCTA are effective in assessing optic nerve fiber integrity and microvascular changes. Microcirculation assessment using OCTA should focus not only on the radial peripapillary capillaries (RPCP), but also on the macular region. Multimodal imaging plays a crucial role in the accurate diagnosis and comprehensive evaluation of patients with ONHD. Further longitudinal studies are needed to investigate how these correlations evolve over time, particularly in the context of ONHD progression.