Inferior Petrosal Sinus Sampling in Cushing’s Syndrome

1. Inferior Petrosal Sinus Samplingin Cushing’s Syndrome Lia Neto Neuroradiology Department – Santa Maria University Hospital, Lisbon - Portugal

2. IPSS in Cushing’s Syndrome - Cushing´s Syndrome - Cortisol

3. IPSS in Cushing’s Syndrome - ACTH Dependent Vs ACTH Independent - 80%

4. IPSS in Cushing’s Syndrome - Biochemical Tests - 80%

5. IPSS in Cushing’s Syndrome - Imaging Tests - 80% • Sensitivity (40-50%) • Adenoma Dimensions • May enhance = parenchyma • “Incidentalomas” (6-10%)

6. IPSS in Cushing’s Syndrome - Inferior Petrous Sinus Sampling - • Sensitivity 88-100% • Specificity 70-100% • Lateralization 70%

7. IPSS in Cushing’s Syndrome - Inferior Petrous Sinus Sampling - CRH (100µg) ACTH IPS / PV ≥ 2 (≥ 3 post CRH) –Pituitary Cushing Synd. IPS / PV  2 – Ectopic Cushing’s Synd. R-PS / L-PS ≥ 1,4 - Lateralization

8. IPSS in Cushing’s Syndrome Objective : • Evaluate the role of simultaneous bilateral catheterization • of the Inferior Petrosal Sinuses: • in the differential diagnosis of Cushing’s Syndrome • in the lateralization assessment of pituitary adenomas

9. IPSS in Cushing’s Syndrome Material and Methods: • Retrospective analysis: 6 patients with CS (1♂ 5♀); 28 – 70 yr • IPSS between 2007-2010 • Sedation & Anticoagulation (5000 U) • Bilateral femoral vein puncture – Bilateral IPS catheterization • Venogram • IPS and peripheral blood sampling pre and post CRH • IPS/peripheral ACTH ratio: Pituitary Vs Ectopic Cushing’s Syndrome • In Cushing’s Disease: lateralization assessment

10. IPSS in Cushing’s Syndrome Results: • Catheterization and sampling was possible in all patients • No complications (technical or clinical) • 2 patients with ectopic ACTH source • 4 patients with Cushing’s Disease

11. IPSS in Cushing’s Syndrome Results: • Clinically (+) • Biochemically (+) • Imaging (-) 35 yr ♀

12. IPSS in Cushing’s Syndrome Results: • Clinically (+) • Biochemically (+) • Imaging (-) 35 yr ♀

13. IPSS in Cushing’s Syndrome Results: • Clinically (+) • Biochemically (+) • Imaging (-) 35 yr ♀ • IPS / PV – 12,5 / 35 • L-IPS / R-IPS – 4

14. IPSS in Cushing’s Syndrome • Clinically (+) • Biochemically (+) • Imaging (inconclusive) Results: 70 yr ♀

15. IPSS in Cushing’s Syndrome • Clinically (+) • Biochemically (+) • Imaging (inconclusive) Results: 70 yr ♀ • IPS / PV – 5 • R-IPS / E-IPS – 6

16. IPSS in Cushing’s Syndrome Results: • Clinically (+) • Biochemically (+) • Imaging (-) 32 yr ♀

17. IPSS in Cushing’s Syndrome Results: • Clinically (+) • Biochemically (+) • Imaging (-) 32 yr ♀ • IPS / PV – 35 • R-IPS / E-IPS – inconclusive

18. IPSS in Cushing’s Syndrome • Originally described by Corrigan and colleagues in 1977 (unilateral venous sampling) • Oldfield et al introduced the bilateral IPSS in the 80´s and in the 90´s the IPSS with and without CRH.

19. IPSS in Cushing’s Syndrome

20. IPSS in Cushing’s Syndrome • The validity of IPSS relies on successful cannulation of the vessels • Anatomic Variations • Alternative Sampling Methods – Cavernous Sinus, Jugular Vein • Possible Complications (0,2%-1,1%) – vein / venule thrombosis or rupture, SAH, ischemia (...)

21. IPSS in Cushing’s Syndrome Conclusion : • IPSS is a safe and well tolerated procedure • Effective in the differential diagnosis of Cushing’s Syndrome • Useful in the localization of microadenomas and surgical planning

22. IPSS in Cushing’s Syndrome Conclusion : The high diagnostic sensitivity, specificity, and accuracy of IPSS have made it a gold standard tool in the investigation of ACTH - dependent Cushing´s syndrome.