Assessment of the accuracy of computed tomography for measurement of normal equine pituitary glands.

The research paper studies the accuracy of Computed Tomography (CT) scans in measuring the dimensions of a normal pituitary gland in horses. The study found that the accuracy varied with the CT scanning technique used, with length and width dimensions being more accurately estimated than height or volume.

Methods

The study used a sample of 25 adult horses that did not show clinical signs of pituitary disease. The following methods were employed:

• Comparison of transverse CT images and gross transverse tissue sections in 2 horses.
• Contrast-enhanced CT scans of the pituitary gland region were conducted postmortem in 23 horses. Different settings were used for slice thickness and intervals (10-mm contiguous or overlapping slices and 4-mm contiguous or overlapping slices).

The CT estimates of pituitary gland dimensions were compared with gross measurements using ANOVA. The accuracy of the CT estimates was determined using the gross measurements as known values.

Results

The study’s results were as follows:

• The pituitary glands were located between the temporomandibular joints and showed contrast enhancement.
• The mean gross measurements were length 2.11 cm, width 2.16 cm, height 0.98 cm, and volume 2.66 cm3.
• The gross measurements and CT estimates of pituitary gland length from 10-mm contiguous and overlapping slices showed no significant difference.
• Similarly, gross measurements and CT estimates of pituitary gland width from 4-mm contiguous and overlapping slices did not show significant differences.
• However, CT estimates of height and volume from all techniques showed differences compared to gross measurements.
• Accuracy levels for CT estimates were 88 to 99% for length, 81 to 92% for width, 58 to 71% for height, and 43 to 55% for volume.

Conclusion

The research concluded that accuracy of CT estimates of pituitary gland dimensions in horses varies with the CT scanning technique used. The estimates for length and width of the glands were more accurate than those for height or volume.