Measures of pituitary gland and stalk: from neonate to adolescence.

Objective: The aim of this study is to provide normative data about pituitary diameters in a pediatric population. Pituitary imaging is important for the evaluation of the hypothalamo-pituitary axis defect. However, data about normal pituitary gland diameters and stalk are limited, especially in children. Structure and the measurements of pituitary gland and pituitary stalk may change due to infection, inflammation, or neoplasia. Methods: Among 14,854 cranial/pituitary gland magnetic resonance imaging scans performed from 2011 to 2013, 2755 images of Turkish children aged between 0 and 18 were acquired. After exclusions, 517 images were left. Four radiologists were educated by an experienced pediatric radiologist for the measurement and assessment of the pituitary gland and pituitary stalk. Twenty cases were measured by all radiologists for a pilot study and there was no interobserver variability. Results: There were 10–22 children in each age group. The maximum median height of the pituitary gland was 8.48 ± 1.08 and 6.19 ± 0.88 mm for girls and boys, respectively. Volumes were also correlated with gender similar to height. Minimum median height was 3.91 ± 0.75 mm for girls and 3.81 ± 0.68 mm for boys. The maximum and minimum pituitary stalk basilar artery ratios for girls were 0.73 ± 0.12 and 0.59 ± 0.10 mm. The ratios for boys were 0.70 ± 0.12 and 0.56 ± 0.11 mm. Conclusion: Our study demonstrated the pituitary gland and stalk size data of children in various age groups from newborn to adolescent. It is thought that these data can be applied in clinical practice. Future prospective followup studies with larger samples, which correlate the structural findings with the clinical and laboratory results are awaited.