Feasibility of high-resolution pituitary MRI at 7.0 tesla

• Published in: European radiology Vol. 24; no. 8; pp. 2005 - 2011
• Main Authors: de Rotte, Alexandra A. J., van der Kolk, Anja G., Rutgers, Dik, Zelissen, Pierre M. J., Visser, Fredy, Luijten, Peter R., Hendrikse, Jeroen
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01-08-2014; Springer Nature B.V
• Subjects: Adult; Contrast agents; Cushing syndrome; Diagnostic Radiology; Feasibility Studies; Female; Head and Neck; Healthy Volunteers; Histopathology; Humans; Imaging; Internal Medicine; Interventional Radiology; Magnetic resonance imaging; Magnetic Resonance Imaging - methods; Male; Medicine; Medicine & Public Health; Neuroradiology; Pituitary ACTH Hypersecretion - diagnosis; Pituitary gland; Prospective Studies; Radiology; Reproducibility of Results; Sinuses; Transplants & implants; Ultrasound; Visualization; Whole Body Imaging - methods; Young Adult; United States > US; Netherlands; Pituitary gland; Magnetic resonance imaging; Cushing’s disease; Pituitary
• ISSN: 0938-7994; 1432-1084
• DOI: 10.1007/s00330-014-3230-x

Objectives
Since the pituitary gland measures 3-8 mm, imaging with the highest possible spatial resolution is important for the detection of even smaller lesions such as those seen in Cushing's disease. In the current feasibility study, we tested a multi-sequence MRI protocol to visualize the pituitary gland in high resolution at 7.0 Tesla (7.0 T).
Methods
Ten healthy volunteers were examined with a 7.0 T pituitary gland protocol. The protocol consisted of a T1-weighted magnetization-prepared inversion recovery (MPIR) turbo spin-echo (TSE) sequence and a T2-weighted TSE sequence. Additionally, this protocol was tested in five patients with clinical and biochemical suspicion of a microadenoma.
Results
The dedicated protocol was successful in visualizing normal pituitary anatomy. At 7.0 T compared to 1.5 T, four times as many slices covered the pituitary gland in sagittal and coronal direction. In three patients, a lesion was diagnosed at 7.0 T, and was confirmed by histopathology to be a microadenoma.
Conclusion
Head-to-head comparisons of 7.0 T with 1.5 T and 3.0 T are needed with larger samples of patients and with imaging times feasible for clinical settings. However, the current study suggests that high-resolution 7.0 T MRI of the pituitary gland may provide new perspectives when used as a second-line diagnostic examination in the specific context of Cushing's disease.
Key Points
•
7.0 T MRI enables ultra-high-resolution imaging of the pituitary gland.
•
7.0 T MRI is appropriate to visualize normal pituitary gland anatomy.
•
The pituitary protocol consists of a T
1
-MPIR-TSE and a T
2
-TSE sequence.
•
In four patients, a suspected ACTH-producing microadenoma was visualized at 7.0 T.
•
Histopathology confirmed three of four lesions to be ACTH-producing microadenomas.