Assessing Olfactory Bulb Infiltration and Morphological Changes in Olfactory Neuroblastoma Using Magnetic Resonance Imaging

Abstract This study aimed to evaluate magnetic resonance imaging (MRI)-based changes in olfactory bulb (OB) volume and area to predict the likelihood of OB invasion in olfactory neuroblastoma (ONB). Retrospective review of MRI data. This study was conducted at the Jikei University, Japan, and the University of North Carolina, United States. The study included 46 ONB-diagnosed patients undergoing MRI and surgical treatment. Preoperative volume and cross-sectional area of the OB were measured, and the surgical pathology of the OB was reviewed. Significant differences in OB metrics were observed between patients with and without OB/tract invasions. Receiver operating characteristic analysis demonstrated high discriminative ability: OB volume (area under the curve [AUC] = 0.971, cutoff 60 mm3) and maximum cross-sectional area (AUC = 0.941, cutoff 9.5 mm2) both showed high sensitivity and specificity for predicting OB invasion. The left–right OB difference, with a lesion/nonlesion ratio exceeding 175%, was a strong predictor. Quantitative MRI metrics of the OB are effective in predicting invasion in ONB. These findings may enhance diagnostic accuracy and influence treatment strategies. Further research is warranted to validate these findings in larger cohorts.