Presentation
ACTH dependent Cushing's syndrome and congestive cardiac failure. CT of the chest, abdomen and pelvis demonstrates no focal abnormality.
Patient Data
Two 3-millimeter areas of delayed enhancement are seen in the pituitary gland, one on the right just posterior to the level of the stalk and the other more centrally at the same level. The pituitary stalk is midline. The optic chiasm and cavernous sinuses are uninvolved, with normal cavernous carotid flow voids.
Conclusion:
Two possible microadenomas. Whether both of these are microadenomas and if so whether both are functional is uncertain.
Bilateral groin punctures were performed and 5 french guiding catheters passed up the IVC, through the right atrium and SVC into the internal jugulars to the base of skull.
Injection of contrast retrogradely opacified the inferior petrosal sinuses which were entered with micro-catheters (right, left) placed equidistant from the pituitary fossa, their position was confirmed with further injections of contrast. Contrast also outlines the sigmoid sinus and transverse sinus.
Following this simultaneous sampling of each microcatheter and the peripheral venous blood (via the groin sheath) was performed pre and post-administration of corticotropin-releasing hormone (CRH).
The venous ACTH levels obtained from the right and left petrosal sinuses and peripheral blood are as follows (00:00 = baseline, other times are in minutes post CRH administration):
- 00:00 right perosal sinus 14.7
- 00:02 right perosal sinus 243
- 00:05 right perosal sinus 139
- 00:10 right perosal sinus 93.0
- 00:15 rigth perosal sinus 58.4
- 00:00 left perosal sinus 8.06
- 00:02 left perosal sinus 81.7
- 00:05 left perosal sinus 81.3
- 00:10 left perosal sinus 11.5
- 00:15 left perosal sinus 8.50
- 00:00 peripheral 1.40
- 00:02 peripheral 1.51
- 00:05 peripheral 1.43
- 00:10 peripheral 2.53
- 00:15 peripheral 3.29
These results are consistent with a pituitary microadenoma, most likely in the right side of the gland.
Case Discussion
On the basis of the IPSS and MRI this patient went on to have an exploratory transphenoidal hypophysectomy. Although histological proof of a microadenoma was not achieved, the patient became biochemically normal following surgery and their ACTH levels returned to normal.
At 18 months follow up remains well with normal pituitary function.
Case courtesy of A/Prof Peter Mitchell, Royal Melbourne Hospital
Unable to process the form. Check for errors and try again.