The biochemical test and pituitary magnetic resonance imaging characteristics in patients with ACTH-dependent Cushing's syndrome

Abstract

Objective: To investigate pituitary images on MRI in patients with ACTH-dependent Cushing's syndrome.

Subject and method: Cross-sectional descriptive study of 15 patients (12 women, 3 men) diagnosed with ACTH-dependent Cushing's syndrome and underwent magnetic resonance imaging of the pituitary gland from October 2022 to October 2023.

Results: Male/female ratio = 1/4. The average age is 38,47 ± 10,78 (the age range from 27 to 62). All patients had plasma ACTH levels >10pg/ ml which is consistent with the clinical diagnosis of ACTH-dependent Cushing's syndrome. Patients with pituitary adenomas observed on MRI account for 80%. The average tumor size is 4,59 ± 1,77mm, 100% of tumors are microadenoma at grade I, stage 0 according to the Hardy-Wilson classification. The group of tumors with isointense signals are highest on both T1W and T2W sequences, at 83,34% and 58,33%, respectively. On the dynamic contrast-enhanced MRI, all tumors appeared as focal areas of lesser enhancement.

Conclusion: Images of pituitary tumors on MRI are very diverse, especially the signal characteristics of the tumor. Evaluating on the dynamic contrast-enhanced MRI accompanies with routine pulse sequences is necessary to diagnose cases of small-sized tumors and isointense signals.