Imaging of pituitary tumours

Area of Science:

• Neuroradiology
• Endocrinology
• Nuclear Medicine

Background:

• Pituitary tumors present diagnostic challenges, requiring detailed anatomical and functional assessment.
• Conventional CT, dynamic CT, and MRI are crucial for evaluating tumor extent and surrounding structures.
• Distinguishing between pituitary and parasellar lesions, and functioning versus non-functioning adenomas, remains complex.

Purpose of the Study:

• To review the role of various imaging modalities in the diagnosis and management of pituitary tumors.
• To highlight the utility of advanced techniques like receptor ligand imaging in specific clinical scenarios.
• To discuss the potential of emerging technologies like PET in pituitary tumor evaluation.

Main Methods:

• Review of neuroradiological techniques including conventional CT, dynamic CT, and MRI.
• Discussion of biochemical tests like BSIPSS for specific conditions (e.g., Cushing's disease).
• Exploration of receptor ligand imaging using SPECT (123I-IBZM, 111In-DTPA-octreotide) and PET.

Main Results:

• Contrast-enhanced MRI and dynamic CT improve sensitivity for microadenomas and macroadenoma invasion.
• Radiological techniques generally cannot differentiate functioning from non-functioning adenomas.
• Receptor ligand imaging aids in characterizing dopamine D2 and somatostatin receptor status, assisting in differential diagnosis and treatment selection.

Conclusions:

• Advanced imaging modalities are essential for comprehensive pituitary tumor assessment.
• Receptor ligand imaging provides valuable functional information, guiding therapeutic decisions and monitoring treatment response.
• Emerging PET applications hold promise for future clinical use in pituitary tumor diagnosis.