Evaluation of radiographic, computed tomographic, and cadaveric anatomy of the head of boa constrictors

Abstract

Objective: To evaluate the radiographic, computed tomographic (CT), and cadaveric anatomy of the head of boa constrictors.

Animals: 4 Boa constrictor imperator cadavers.

Procedures: Cadavers weighed 3.4 to 5.6 kg and had a body length ranging from 189 to 221 cm. Radiographic and CT images were obtained with a high-detail screen-film combination, and conventional CT was performed with a slice thickness of 1.5 mm. Radiographic images were obtained in ventrodorsal, dorsoventral, and left and right laterolateral recumbency; CT images were obtained with the animals positioned in ventral recumbency directly laying on a plastic support. At the end of the radiographic and CT imaging session, 2 heads were sectioned following a stratigraphic approach; the other 2, carefully maintained in the same position on the plastic support, were moved into a freezer (-20°C) until completely frozen and then sectioned into 3-mm slices, respecting the imaging protocol. The frozen sections were cleaned and then photographed on each side. Anatomic structures were identified and labeled on gross anatomic images and on the corresponding CT or radiographic image with the aid of available literature.

Results: Radiographic and CT images provided high detail for visualization of bony structures; soft tissues were not easily identified on radiographic and CT images.

Conclusions and clinical relevance: Results provide an atlas of stratigraphic and cross-sectional gross anatomy and radiographic and CT anatomy of the heads of boa constrictors that might be useful in the interpretation of any imaging modality in this species.