Ultrasound-Guided Jugular Vein Access for Inferior Petrosal Sinus Sampling: A Safe and Feasible Technique

Pituitary Cushing's disease (CD) results from excessive adrenocorticotropic hormone (ACTH) secretion, usually due to a pituitary adenoma. This report describes the diagnostic approach and management of a complex case of CD in a patient with multiple comorbidities, highlighting a hybrid technique for inferior petrosal sinus sampling (IPSS) when standard access fails. A woman with poorly controlled diabetes, obesity, chronic kidney disease (CKD), and hypertension presented with suspected Cushing's syndrome. Despite normal urinary free cortisol (UFC) levels (likely influenced by renal dysfunction), clinical suspicion prompted further testing, which revealed an inverted cortisol rhythm and lack of suppression on low-dose dexamethasone. High-dose suppression indicated a pituitary source. MRI findings were inconclusive. To confirm the diagnosis, bilateral IPSS was attempted. Right petrosal sinus catheterization via femoral access was successful; however, left-sided access failed. An alternative, ultrasound-guided direct left internal jugular puncture was performed, allowing complete sampling. A central-to-peripheral ACTH gradient >2 at baseline and >3 after desmopressin confirmed a pituitary source. The patient subsequently underwent successful transsphenoidal resection, achieving postoperative biochemical remission. IPSS remains the gold standard for distinguishing central from ectopic ACTH production. While bilateral femoral access is standard, anatomical variants may necessitate alternative routes. This case demonstrates the feasibility and safety of combining femoral and direct jugular access to complete IPSS when conventional approaches are limited. This is the first reported case of IPSS performed using a hybrid right femoral and left ultrasound-guided jugular approach, offering a practical alternative when femoral access is not feasible and reinforcing the diagnostic value of IPSS in challenging cases.