Purpose: The pituitary or infundibular stalk is an anatomically important structure identified routinely in radiologic imaging for the evaluation of pituitary and suprasellar lesions. The morphometry of the pituitary stalk with 1.5 T MR images was useful in diagnosing the infundibular lesion and to assess the efficacy of treatment given by chemotherapy for many pathological conditions. The normative data for the length, the thickness of the stalk, and the infundibular recess are inadequate in the literature. There are no data regarding the morphometry of the pituitary stalk in the adult population.
Methods: One hundred and fifty normal brain MR images (75 males and 75 females) were analyzed for the evaluation of stalk and other parameters. Mean and the standard deviation were calculated. The unpaired t test was used to assess any significant difference between age-groups and gender. The intraclass coefficient correlation was used to analyze the inter-observer variability.
Results: The mean length of the stalk was 0.55 ± 0.16 mm. There was a significant difference (p < 0.05) in the length between the genders. The mean diameter of the stalk at the level of optic chiasma was 0.24 ± 0.06 mm, and the infundibular depth was 0.52 ± 0.12 mm. There was no significant difference between the genders in the thickness of the stalk and the depth of the recess.
Conclusion: The normative data from the present study can be used as a screening tool for diagnosis as well as to assess the effect of treatment in pituitary infundibular lesions. These normative data shall be of help in the evaluation of stalk in various neurosurgical and endocrinological pathologies and lead the radiologist and endocrinologist in the early diagnosis and management of hypothalamo-pituitary axis diseases.
Keywords: Fenderson’s funnel; Infundibulum; MRI; Morphometry; Pituitary stalk.