Visual function and cerebrospinal fluid volume along the optic nerve in patients with spontaneous cerebrospinal fluid rhinorrhea: a cross-sectional study.

BACKGROUND: The aim of the present study was to establish a mathematical reconstruction model to analyze cerebrospinal fluid (CSF) dynamics along the optic nerve (ON). Visual function and its correlation with CSF dynamics along the ON were explored in patients with spontaneous CSF rhinorrhea. METHODS: Neuro-ophthalmological evaluations, including intraocular pressure (IOP), best-corrected visual acuity (BCVA), and visual field (VF) tests, as well as optical coherence tomography (OCT), were performed in 25 patients with spontaneous CSF rhinorrhea and 25 normal controls (NCs). In the patient group, CT cisternography images were reconstructed, and the contrast-loaded CSF (CLCSF) volume along the ON was calculated by nnU-Net, a deep-learning method. Correlations among the CLCSF volume along the ON, CSF pressure (CSFP) and neuro-ophthalmological parameters were analyzed. RESULTS: The neuro-ophthalmological analyses revealed significant differences in the BCVA, visual field index (VFI), mean deviation (MD), and pattern standard deviation (PSD) between patients and NCs. Correlation analysis revealed that the CLCSF volume along the ON was correlated with IOP and CSFP in eyes on the ipsilateral side of leakage and strongly correlated with the thickness of the GCC and circumpapillary retinal nerve fiber layer (cpRNFL) in eyes on the contralateral side of leakage. CONCLUSION: Subtle functional visual changes are present in patients with spontaneous CSF rhinorrhea, manifesting as decreased visual acuity and VF defects. The CLCSF volume along the ON is correlated with CSFP and affects retinal thickness.