Objectives: To evaluate the potential diagnostic role and sensitivity of T2-weighted DRIVE sequence in pituitary stalk (PS) identification and measurements in patients with hypothalamic-pituitary disorders. The degree of agreement and reliability between standard pre- and post-contrast T1-weighted images and T2-DRIVE will be tested in a large group of patients with pituitary dysfunction.
Design: We searched for pituitary MRI reports using T2-DRIVE in our Institutional database between 2006 and 2015. Among 135 eligible patients, 102 showed eutopic posterior pituitary(PP)gland and 33 showed ectopicPP(EPP).
Methods: In patients with eutopic PP, two readers measured the PS size in the sagittal plane, drawing a line perpendicular to the axis of the major stem at three levels: proximal, midpoint, and distal on pre- and post-contrast T1-weighted and on T2-DRIVE images. The pituitary stalk was assessed on pre-contrast T1 and T2-DRIVE sequences in those with EPP. Cohens kappa coefficient was then used to evaluate the chance-correct concordance for the case between two different sequences that are expressed in the form of categorical data.
Results: The agreement between the measurements of the two readers showed that the ICC in the T2-DRIVE sequence was 0.96 at the proximal level of the PS, 0.99 at the midpoint level and 0.97 at the distal level. In pre-contrast T1-weighted sequence, the ICC was 0.89 (proximal part), 0.85 (midpoint), and 0.76 (distal part). Finally, on the post-contrast T1, the ICC was 0.88 at the proximal, 0.87 at the midpoint and 0.79 at the distal PS levels. A significant difference between the ICC on the T2-DRIVE and the pre-and post-contrast T1-weighted sequences was demonstrated. The percentage of PS identified by T2-DRIVE in EPP patients was 72.7% compared to 30.3% of T1 pre-contrast sequences. A significant association was found between the visibility of PS on T2-DRIVE and the height of AP.
Conclusion: T2-DRIVE sequence is precise and reliable for the evaluation of PS size and the recognition of PS abnormalities; the use of gadolinium does not add significant information. T2-DRIVE images allow for a better diagnosis of pituitary gland and PS disorders. A sagittal T2-DRIVE sequence without gadolinium takes less than 3 minutes to acquire, and its inclusion into routine sellar MRI protocols is recommended as a valid alternative to post-contrast imaging which - also in view of safety issues - may be avoided in subjects with pituitary disorders without evident sellar/suprasellar mass lesions.
27 - 29 Sep 2018
European Society for Paediatric Endocrinology