Dynamic computed tomographic evaluation of the pituitary gland in healthy dogs.
OBJECTIVE
To determine the contrast enhancement pattern of the pituitary gland in healthy dogs via dynamic computed tomography (CT).


METHODS
17 dogs.


METHODS
With each dog in sternal recumbency, transverse CT scans were made perpendicular to the skull base from the rostral clinoid processes to the dorsum sellae. At the position of the image that contained the largest cross section of the pituitary gland, a series of 9 to 11 scans was made during and after IV injection of contrast medium (dynamic CT scans). The contrast enhancement pattern of the pituitary gland and surrounding arteries was assessed visually and by use of time-density curves.


RESULTS
After strong enhancement of the maxillary arteries, the intracavernous parts of the internal carotid arteries, and the communicating arteries of the arterial cerebral circle, there was a strong enhancement of the central part of the pituitary gland followed by enhancement of its peripheral part. On the last images of the dynamic series of the pituitary gland, the central part was hypodense, compared with the peripheral part. Time-density curves confirmed an early, strong enhancement of the central part and a delayed, less strong enhancement of the peripheral part of the gland.


CONCLUSIONS
The difference in enhancement between the central and peripheral parts of the pituitary gland was attributable to a difference in vascularization of the neurohypophysis and adenohypophysis, respectively. Distortion or disappearance of the strong central enhancement (pituitary flush) may be used for the detection and localization of pituitary abnormalities in the adenohypophysis.
van der Vlugt-Meijer
Roselinda H
RH
Division of Diagnostic Imaging, Faculty of Veterinary Medicine, Utrecht University, 3508 TD Utrecht, The Netherlands.
Meij
Björn P
BP
Voorhout
George
G
D000818:Animals; D003287:Contrast Media; D004285:Dogs / Q000033:anatomy & histology*; D007091:Image Processing, Computer-Assisted; D010902:Pituitary Gland / Q000000981:diagnostic imaging*; D013997:Time Factors; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000662:veterinary*
D003287:Contrast Media