Ultrasonographic characteristics of both adrenal glands in 15 dogs with functional adrenocortical tumors

Abstract

Ultrasonographic examination of both adrenal glands was performed in 15 dogs with functional adrenocortical tumors (FAT). Bilateral adrenal tumors were diagnosed in three of 15 dogs, and unilateral tumors were diagnosed in 12 of 15 dogs. Adrenal tumors were characterized by adrenal gland enlargement with loss of the normal shape and parenchymal structure. The contralateral adrenal gland could be imaged in all dogs with unilateral tumors. Based on size, shape, and parenchymal structure, the contralateral adrenal gland was similar to adrenal glands of normal dogs. The results of this study show that: 1) both adrenal glands should be imaged routinely in dogs with hyperadrenocorticism; 2) bilateral adrenocortical tumors seem to be more frequent than previously assumed; 3) one normal adrenal gland does not exclude the existence of a contralateral FAT; and 4) the functional atrophy of the contralateral adrenal gland in dogs with FAT may not be apparent ultrasonographically.

Long‐Term Survival of Dogs with Adrenal‐Dependent Hyperadrenocorticism: A Comparison between Mitotane and Twice Daily Trilostane Treatment

“…Ultrasonographic evaluation of the adrenal glands demonstrated unilateral masses in most cases and bilateral masses in 3 (12%). Similar findings have been previously reported 18. Tumor thrombi also were detected in a similar proportion of dogs (15%) to that previously reported 3…”

Ultrasonographic Adrenal Gland Measurements in Clinically Normal Small Breed Dogs and Comparison with Pituitary-Dependent Hyperadrenocorticism

“…CT and MRI enable visualization of the adrenal glands in dogs and may be useful in differentiating bilateral adrenal hyperplasia from unilateral adrenal gland neoplasia. However, these techniques are time consuming, require general anesthesia and are not readily available [1,12,17]. Ultrasonography is the most popular screening test for assessing the adrenal glands in dogs on the basis of the advanced ultrasound machines available and accumulated experience [2,9,10].…”

“…However, that study was performed on dogs with body weights ranging from 1.8 to 70 kg [4]. Another study performed on 15 dogs with functional adrenal tumors enrolled 14 small breed dogs and 1 Rhodesian Ridgeback, and the body weights ranged from 3 to 30 kg [12]. Therefore, it is not clear that the 7.5 mm cut-off is a reliable criterion across all breeds and body weights; adrenal size may depend to some extent on body weight, and the sensitivity and specificity values assessed using the 7.5 mm cut-off may be falsely elevated [8,10].…”

“…Ultrasonography has been determined to be a useful primary screening modality to identify abnormal adrenal glands, such as pituitary-dependent hyperadrenocorticism (PDH), adrenal neoplasms of the cortex and medulla and hypoadrenocorticism [2,3,7,[9][10][11][12][13]. Adrenal size has been used as the principal criterion for differentiating a normal adrenal gland from adrenal hyperplasia [2].…”

Hyperparathyroidism in dogs with hyperadrenocorticism

“…Differentiation between pituitarydependent HAC and adrenal-dependent HAC was achieved using a combination of adrenal ultrasonography, endogenous ACTH concentration and the results of the low-dose dexamethasone suppression test using criteria described elsewhere (Feldman and others 1996, Hoerauf and Reusch 1999, Gould and others 2001.…”