MRI features of craniopharyngiomas in different age groups and pathological subtypes.

Objective: To investigate the MRI features of different pathological types in adult and juvenile patients with craniopharyngioma. Materials and methods: The preoperative MRI images of 68 patients with pathologically confirmed craniopharyngioma were retrospectively analyzed. The tumor location, imaging findings and surrounding tissue involvement were determined, and the tumor volume was measured. The differences of these imaging indicators and pathological types between 48 adult and 20 juvenile groups were compared. Results: Grouped by age: The proportions of adamantinomatous craniopharyngioma (ACP) in the juvenile group and adult group were 85.0% and 56.3%, respectively, with a significant difference (P = 0.024). The predilection sites of craniopharyngioma differed between the juvenile and adult groups. Tumors in the juvenile group were most frequently located in the intrasellar or suprasellar region (80%), whereas those in the adult group were predominantly suprasellar (60.4%), with a significant difference (P<0.001). The incidence of tumor calcification was 55.0% in the juvenile group and 29.1% in the adult group, with a significant difference (P = 0.044). Grouped by pathological subtype: The mean ages at onset were 27 years for ACP and 43 years for SPCP, with a significant difference (P<0.001). The incidence of cystic degeneration was 95.5% in ACP and 83.3% in SPCP, with a significant difference (P = 0.037). Fluid-fluid levels or sediment were present in 20.5% of ACP, but absent in all SPCP, with a significant difference (P = 0.022). Patients in the non-third ventricular floor invasion group were younger and had a wider age range than those in the third ventricular floor invasion group(P = 0.025). Conclusion: There is a close correlation between age at onset, pathological subtype, and MRI features of craniopharyngiomas. ACP is more common in juvenile patients, with a higher tendency toward intrasellar/suprasellar location, calcification, and cystic degeneration. In adult patients, lesions are predominantly suprasellar and more frequently accompanied by pituitary involvement. ACP show a higher cystic degeneration rate with characteristic fluid-fluid levels or sediment, which can be used for preoperative pathological differentiation. Meanwhile, invasion of the floor of the third ventricle is more commonly seen in older patients, suggesting that age may assist in evaluating the invasive growth pattern of craniopharyngiomas.