Multimodal Imaging of the Nasopalatine Canal: Morphometric Characteristics and Signal Intensity Assessment

The nasopalatine canal (NPC) is an essential anatomical structure in the anterior maxilla, linking the nasal and oral cavities. Its morphology is critical for oral surgery, anesthesia, and implant planning. This study aimed to provide a comprehensive evaluation of the NPC by combining computed tomography (CT) and magnetic resonance imaging (MRI) to assess canal morphology and signal characteristics.

A total of 346 CT and MRI images from patients aged 18 years and older (173 males, 173 females; mean age 53.35 ± 19.8 y) were analyzed. Axial and coronal MRI and sagittal CT sections were evaluated for canal shape, number, length, and signal intensity.

The mean lengths of the incisive and nasopalatine foramina were found as 6.66 ± 2.2 mm and 3.2 ± 1.5 mm, respectively. Axial canal shapes were predominantly round or oval (63.01%), while 47.69% exhibited a Y-shaped configuration in the coronal plane. Anterior tooth loss was present in 39.5% of patients and was significantly associated with changes in foramen dimensions (P < 0.001). The mean FLAIR T2 MRI signal intensities for the incisive and nasopalatine foramina were 643.64 ± 246.38 and 585.46 ± 214.27, respectively. Diagnostic thresholds for normal signal intensity were calculated as 1.136 for the incisive foramen and 1.013 for the nasopalatine foramen.

These findings suggest that FLAIR T2 MRI signal intensity may serve as a diagnostic marker for NPC assessment. Furthermore, anterior tooth loss appears to influence the dimensions of the incisive foramen. Future studies should validate these MRI thresholds and explore longitudinal changes in NPC morphology.