Evaluation of the pterygoid process pneumatization and sclerosis with Vidian canal morphology using computed tomography: a comparative study in nasopharyngeal carcinoma patients and healthy controls

BACKGROUND: To evaluate the morphological characteristics of the pterygoid process - including pneumatization and sclerosis - alongside vidian canal (VC) type and length in patients with nasopharyngeal carcinoma (NPC) compared to healthy controls using computed tomography (CT). MATERIALS AND METHODS: This retrospective study included 200 subjects, comprising 38 patients with histopathologically confirmed NPC and 162 age- and sex-matched healthy controls. All CT scans were acquired using a standardized protocol with thin-slice axial images and multiplanar reconstructions. Evaluated features included pterygoid process pneumatization and sclerosis, VC type (classified as Type 1-3), and VC length bilaterally. RESULTS: Pterygoid process pneumatization showed no statistically significant difference between the NPC and control groups (right: 21.1% vs 24.7%, p = 0.794; left: 21.1% vs 18.5%, p = 0.898). In contrast, right-sided pterygoid plate sclerosis was significantly more frequent in NPC patients (68.4%) than in controls (4.9%) (p < 0.005). Significant differences in VC types were found between groups. Type 3 canals were more common in NPC patients (right: 39.5%, left: 39.5%) than in controls (right: 21.0%, left: 23.5%), while Type 2 was reduced in the NPC group (right and left: 15.8%) vs controls (right: 33.3%, left: 34.6%); significant for both sides (right: p = 0.024; left: p = 0.038). VC length was also significantly greater in the NPC group (right: 14.18 mm; left: 13.08 mm) compared to controls (right: 12.25 mm; left: 12.35 mm). The VC length positively correlated with age (right: r = 0.267; left: r = 0.339). CONCLUSIONS: Sclerosis of the right pterygoid plate and an increased prevalence of Type 3 VCs were significantly associated with NPC. Anatomical variations in VC type and length may have diagnostic implications in radiological interpretation and radiotherapy planning in NPC patients.