Objective—To describe the anatomic features of the
pituitary gland region in horses via computed tomography
(CT) and determine the accuracy of CT for estimating
normal equine pituitary gland dimensions.
Animals—25 adult horses with no clinical signs of
Procedure—Transverse CT images and gross transverse
tissue sections were compared in 2 horses.
Contrast-enhanced CT of the pituitary gland region
was performed postmortem in 23 horses with 4 slice
thickness and interval settings (10-mm contiguous or
overlapping slices and 4-mm contiguous or overlapping
slices). Gross and CT estimates of pituitary gland
dimensions were compared via ANOVA. Accuracy of
CT estimates was calculated with gross pituitary
gland measurements as the known value.
Results—Pituitary glands were located between the
temporomandibular joints and had contrast enhancement.
Mean gross dimensions were length, 2.11 cm;
width, 2.16 cm; height, 0.98 cm; and volume, 2.66
cm3. Gross measurements and CT estimates of pituitary
gland length from 10-mm contiguous and overlapping
slices did not differ. Gross measurements and
CT estimates of pituitary gland width from 4-mm contiguous
and overlapping slices did not differ. Estimates
of height and volume from all CT techniques differed
from gross measurements. Accuracies for CT estimates
were length, 88 to 99%; width, 81 to 92%;
height, 58 to 71%; and volume, 43 to 55%.
Conclusions and Clinical Relevance—Accuracy of
estimates of pituitary gland dimension in horses varied
with CT scanning technique; via CT, estimates of
length and width of glands were more accurate than
estimates of height or volume. (Am J Vet Res 2003;64:1387–1394)