title: Dynamic computed tomography of the pituitary gland using a single slice scanner in dogs with pituitary-dependent hypercortisolism.
abstract: Selective removal of the pituitary adenoma has not been advocated in dogs with pituitary-dependent hypercortisolism because the pituitary adenoma is usually not visualized on routine computed tomography (CT). Dynamic pituitary CT scanning is aimed at the detection of the pituitary flush and, indirectly, at the presence and position of the adenoma. The first aim of this retrospective study was to compare findings of a multiple slice dynamic scanning protocol with those of a single slice dynamic protocol using a single slice CT scanner. The second aim was to compare the CT findings with surgical findings, and surgical findings with histopathological findings. Computed tomography with single and multiple slice dynamic scanning protocols was performed in 86 dogs with pituitary-dependent hypercortisolism. Thirty dogs underwent transsphenoidal hypophysectomy and pituitary specimens were collected as tumor, normal, mixed and neurohypophyseal samples and processed for histology. The pituitary flush was not detected more frequent in multiple slice dynamic scanning series than in single slice dynamic scanning series. However, in non-enlarged pituitaries, the flush was seen significantly more frequently than in enlarged pituitaries. Prediction of the nature of the tissue during hypophysectomy by the surgeon was inconclusive. In conclusion, when using a single slice CT scanner, both single or multiple slice dynamic scanning protocols can be used for localization of the neurohypophyseal flush, and, indirectly, the adenoma. However, based on this study, the aim of surgery in dogs with pituitary-dependent hypercortisolism remains total adenohypophysectomy, and when the neurophypophysis is recognized, it may be left in situ.
authors.affiliation: Department of Veterinary Medical Sciences, School of Agriculture and Veterinary Medicine, University of Bologna, via Tolara di Sopra, 50, 40064 Ozzano dell'Emilia, Italy.
authors.forename: Sara
authors.initials: S
authors.lastname: Del Magno
authors.affiliation: Department of Pathobiology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, The Netherlands.
authors.forename: Guy C M
authors.initials: GCM
authors.lastname: Grinwis
authors.affiliation: Division of Diagnostic Imaging, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 108, 3584 CM Utrecht, The Netherlands.
authors.forename: George
authors.initials: G
authors.lastname: Voorhout
authors.affiliation: Department of Clinical Sciences of Companion Animals, Faculty of Veterinary Medicine, Utrecht University, Yalelaan, 108, 3584 CM Utrecht, The Netherlands. Electronic address: b.p.meij@uu.nl.
authors.forename: Björn P
authors.initials: BP
authors.lastname: Meij
mesh_terms: D000236:Adenoma / Q000662:veterinary; D000818:Animals; D004283:Dog Diseases / Q000000981:diagnostic imaging* / Q000473:pathology; D004285:Dogs; D005260:Female; D007016:Hypophysectomy / Q000662:veterinary; D047748:Pituitary ACTH Hypersecretion / Q000000981:diagnostic imaging / Q000662:veterinary*; D010902:Pituitary Gland / Q000000981:diagnostic imaging / Q000473:pathology*; D010911:Pituitary Neoplasms / Q000175:diagnosis / Q000000981:diagnostic imaging / Q000662:veterinary*; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods / Q000662:veterinary*
keywords: Dog; Dynamic computed tomography; Hypercortisolism; Hypophysectomy; Pituitary gland