Background: Conventional magnetic resonance imaging (MRI) is adversely affected by thick slices, small intersection gaps, and the partial volume effect, leading to the missed diagnosis or misdiagnosis of pituitary micro-lesions.
Purpose: To evaluate the diagnostic yield of three-dimensional sampling perfection with application-optimized contrasts using different flip-angle evolutions (3D-T2 SPACE) sequences compared with a standard MRI protocol for the diagnosis of pituitary micro-lesions.
Material and methods: The MRI findings of 664 patients with clinically suspected pituitary lesions were retrospectively analyzed. All patients underwent coronal 3D-T2 SPACE sequences followed by T1-weighted (T1W) imaging. Conventional scanning sequences included coronal and sagittal T1W imaging and post-contrast enhanced coronal and sagittal T1 imaging. All images were independently evaluated by two experienced neuroradiologists. The inter-observer agreement was analyzed using kappa statistics.
Results: Compared with conventional sequences, there was an increase in diagnostic confidence of 60.3% for the diagnosis of pituitary micro-lesions with the addition of 3D-T2 SPACE sequences. The lesion conspicuity scores of combined conventional and 3D-T2 SPACE sequences were significantly higher than those of conventional imaging (z = -6.403, P < 0.01) and 3D-T2 SPACE sequences (z = -4.243, P < 0.01). In addition, the inter-observer agreement of 3D-T2 SPACE sequences was good (κ = 0.826).
Conclusion: Combined with routine sequences, post-contrast enhanced 3D-T2 SPACE sequences effectively improve diagnostic confidence in the diagnosis of pituitary micro-lesions. Post-contrast enhanced 3D-T2 SPACE is suitable for detecting pico-adenomas, micro-lesions adjacent to the cavernous sinuses or sellar floor, lesions between the anterior and posterior lobes, and lesions with early phase enhancement.
Keywords: 3D-T2 SPACE; micro-lesions; pituitary gland.