Association of neurite orientation dispersion and density imaging with cognitive impairment in nasopharyngeal carcinoma patients with radiation-induced temporal lobe injury.

BACKGROUND

To evaluate whether neurite orientation dispersion and density imaging (NODDI) can reflect cognitive impairment (CI) in nasopharyngeal carcinoma (NPC) patients with late-delayed radiation-induced temporal lobe injury (RTLI).

METHODS

In this prospective study, 90 NPC patients with RTLI underwent structural MRI, conventional diffusion-weighted imaging, and NODDI. Cognitive function was assessed using the Montreal Cognitive Assessment (MoCA; score < 26 indicated CI). NODDI-derived parameters-intra-neurite volume fraction (ICVF), isotropic volume fraction (ISOVF), and orientation dispersion index (ODI)-and apparent diffusion coefficient (ADC) were compared between patients with and without CI. Diagnostic performance and correlations with MoCA scores were analyzed.

RESULTS

Among 90 patients, 66 had CI. CI patients exhibited significantly lower ICVF and ODI (p < 0.001, p = 0.047, respectively), while ISOVF and ADC did not differ (p > 0.05). ICVF demonstrated superior discriminative performance (AUC = 0.869) versus ODI (AUC = 0.638). Correlation analyses demonstrated a strong positive association between ICVF and the MoCA scores (ρ = 0.781, p < 0.001), a weak negative correlation for ISOVF (ρ = -0.310, p = 0.003) and ADC (ρ = -0.215, p = 0.041), and no significant correlations for ODI.

CONCLUSION

NODDI-derived ICVF is associated with CI and correlates with MoCA scores in NPC patients with RTLI.