S BOUABIDI ,S JERBI OMEZZINE , Z KHADIMALLAH, K BOUSLEMA, B ZANTOUR* H A HAMZA

Department of Medical Imaging, Tahar Sfar University Hospital Center Mehdia, Tunisia

*Department of Internal Medecine, Tahar Sfar University Hospital Center Mehdia, Tunisia

PITUITARY STALK TRANSECTION SYNDROME : A LATE REVELATION

NR12

INTRODUCTIONGrowth hormone deficiency is a common endocrinologic cause of short stature:

Idiopathic Associated with organic causes( tumors , surgery)

Pituitary stalk transection is a non-negligible cause of growth hormone (GH) deficiency

Multifaceted presentation in childhood

MRI: • Imaging modality of choice • Anatomic details Study of the pituitary- hypothalamic region• Pathognomonic findings

We report the case of a 20 year old male to illustrate the particularities of late revelation of this syndrome

Patients and Methods:A 20 year old male Growth retardationPast history: No foetal distress No cranial trauma

Biological assessment, Anterior pituitary function exploration

Brain MRI were performed

Results:Biological assessment: No kind of misabsorption

Anterior pituitary function exploration: GH and Gonadotropin deficiency

MRI: Hypoplasia of the anterior hypophysis

Absence of pituitary stalk

Ectopic posterior hypophysis

Gadolinium-enhanced coronal T1-weighted MR images : The pituitary stalk is not visibile (arrow)

Gadolinium-enhanced coronal T1-weighted MR images: Ectopic posterior pituitary gland (arrow) which is seen as an area of high signal intensity in the midline

Unenhanced midline sagittal T1-weighted MR image shows the small anterior pituitary gland (short arrow) and ectopic posterior pituitary gland (long arrow)

DISCUSSION:Isolated growth hormone deficiency and multiple pituitary hormone deficiency can be part of the pituitary stalk transection syndrome

The pituitary stalk transection syndrome should be considered in patients who were previously thought to have idiopathic GH deficiency or multiple pituitary hormone deficiencies

Magnetic resonance imaging (MRI) :

The diagnostic method of choice for idiopathic hypopituitarismExcellent definition of the hypothalamic pituitary region Gadolinium injection is necessary for a better description of the stalk

Imaging characteristics of this syndrome :

Lack of pituitary stalk visibility ( after injection of a gadolinium-enhanced contrast ) Hypoplasia of the anterior hypophysis Ectopic posterior pituitary gland

Anatomical variations in the location of the high intensity signal of the posterior pituitary seen on T1-weighted MRI may occur infrequently and have to be differentiated from a stalk-located lipoma

Presence of MRI characteristics compatible with the pituitary stalk transection syndrome should prompt a full pituitary hormonal evaluation

Patients require regular clinical survey and hormonal controlsProgression to complete anterior pituitary hormone deficiency may occur, even during the 2nd or the 3rd decade of life

CONCLUSION:

Stalk transaction syndrome :Relatively frequent should be considered in patients who were previously thought to have idiopathic GH deficiency or pituitary hormone deficiencyMRI :the diagnostic method of choice showing pathognomonic characteristicsRequire regular clinical survey and hormonal controls