How is IPSS performed?
How do we do an IPSS procedure? Typically under general anesthesia, we place small tubes (catheters) into the femoral veins (the main vein draining the legs) at the level of the groin. From there, under X-ray guidance, we navigate those catheters to the main veins which drain the Pituitary gland.
What is CRH stimulation test?
The corticotropin-releasing hormone (CRH) stimulation test is a second-line non-invasive dynamic test for precise localization of disease in which at least a 35-50% increase of ACTH and 20% increase of cortisol concentrations from baseline indicate the pituitary gland as the origin of hypercortisolemia (7-9).
What is Nelson’s syndrome?
Nelson syndrome is a disorder characterized by abnormal hormone secretion, enlargement of the pituitary gland (hypophysis), and the development of large and invasive growths known as adenomas. It occurs in an estimated 15 to 25 percent of people who undergo surgical removal of the adrenal glands for Cushing disease.
What is empty sella?
Empty sella syndrome is a rare disorder characterized by enlargement or malformation of a structure in the skull known as the sella turcica. The sella turcica is a saddle-shaped depression located in the bone at the base of skull (sphenoid bone), in which resides the pituitary gland.
What is the inferior petrosal sinus?
The inferior petrosal sinus is a paired cranial venous channel that drains the cavernous sinus, midbrain, cerebellum and inner ear. This dural venous sinus emerges from the cavernous sinus within the middle cranial fossa and drains into the internal jugular vein.
How are ACTH values obtained from the inferior petrosal sinus?
The technique is performed by cannulation of the bilateral femoral veins, and advancing catheters into the inferior petrosal sinuses via the internal jugular veins. Baseline ACTH values are obtained from the periphery and the inferior petrosal sinuses both before and after CRH stimulation (1 μg/kg of body weight).
When to use CRH or inferior petrosal sinus sampling?
Bilateral inferior petrosal sinus sampling ( BIPSS ): Simultaneous bilateral sampling from the inferior petrosal sinuses, with the adjunctive use of CRH remains the gold standard for differentiating between pituitary and non-pituitary sources of ACTH, with sensitivity and specificity of 94%.
Is there such a thing as an asymmetric inferior petrosal sinus?
Asymmetric inferior petrosal sinuses (IPS) are not infrequently encountered during bilateral IPS sampling. There is little data on whether IPS symmetry influences success in predicting the adenoma side in patients with ACTH -dependent Cushing’s syndrome (CS).
When was inferior petrosal sinus sampling ( IPSS ) established?
Inferior petrosal sinus sampling (IPSS) as a diagnostic tool in the differential diagnosis between pituitary-dependent and ectopic ACTH syndrome was established in the 1970s (1, 23, 24, 25).