CT anatomy of the lungs, bronchi and trachea in the Mature Guinea pig (cavia porcellus)

BACKGROUND

Since there is no complete study of topographic features of thorax structures in guinea pigs, this study strives to define the exact topographic features of thorax structures.

OBJECTIVES

The aim of this study is to provide comprehensive topographic information about the location of the trachea, bronchi, lungs and heart inside the thoracic cavity in guinea pig, as well as to study the features of these structures, their proximity to other organs and comparative anatomical studies with CT scan images in living samples.

METHODS

Ten adult male and healthy guinea pigs were selected. CT scan transverse images were taken. The morphometric parameters of the lungs, bronchi, trachea, heart, thoracic cavity and abdominal cavity were measured.

RESULTS

In these studies, the position of organs such as the trachea, lungs and heart were monitored, and specified descriptions of CT scan images and anatomical observations were obtained. We realised that the heart in this animal was not inclined to the left, and due to the equal size of the lungs, the heart was almost on the midline. According to the measurements, 20.05% of the ventral cavity volume was thoracic cavity and 79.95% was abdominal cavity.

CONCLUSIONS

According to studies on guinea pigs, the right and left have the volume, and the heart is located between them on the midline without a tendency to the left. It seems that one of the reasons for the reluctance of the heart to the left and its placement on the midline in the guinea pig is that the volume of the two lungs is equal. In the case of guinea pigs, both numerical parameters are smaller than rabbits', but close to it. One of the most important factors in this study is that none of the animals were euthanised, and all of samples were alive after our study.

Anatomical study of the scleral ring and eyeball of the long-eared owl (Asio otus) with anatomical methods and diagnostic imaging techniques

BACKGROUND

The scleral ring in birds consists of ossicles that are fixed as small plates by cartilage joints and have no articulation to other parts of the skeleton.

OBJECTIVE

Due to inadequate examination of the scleral ring anatomy and its specific form in owls, this study aimed to investigate the exact structure of the scleral ring and some morphometric characteristics of the eyeball in a long-eared owl (Asio otus).

METHODS

The eyes of 20 alive and 10 dead male and female owls were examined. In addition to common anatomical methods, computed tomography scans and radiographic and ultrasonographic imaging techniques were used in this study.

RESULTS

The structure consisted of 15 ossicles. In the ventral part of the ring, these tubercles were observed in the scleral rings of all owls; in each ring, there were four bones with these tubercles. Additionally, there was no significant difference between the left and right eye parameters. Most ocular parameters in female owls were larger than those in males, but in the case of some parameters, such as optic nerve length and optic nerve sheath diameter, this difference was not observed.

CONCLUSIONS

According to this study, the scleral ring in the Asio otus has anterior and posterior parts, and the lens is in the immediate vicinity of the anterior part. The right and left scleral rings and eyeballs are bilaterally symmetrical in terms of the shape, size, and number of ossicles that form the ring.

Creating a cross-sectional, CT and MR atlas of the Pannon minipig

PURPOSE

The purpose of this study was to create a detailed cross-sectional anatomical reference atlas of the Pannon minipig by correlating good resolution CT and MR images with high quality cross-sectional anatomical images. According to the authors knowledge, no detailed anatomical atlas is available for the minipig.

MATERIAL AND METHOD

An adult female minipig was utilized for this purpose. The animal was placed in a PVC half tube, and CT generated images of 0.6 mm slice thickness and MR images of 1.41 mm slice thickness were obtained. The images covered the whole body from the most rostral portion of the snout to the tip of the tail. The CT and MR scans were aligned with frozen anatomical sections prepared with an anatomical band saw from the same animal and significant structures were identified and labelled. The terminology employed has been referenced from the Nomina Anatomica Veterinaria 6th edition-2017.

FINDINGS AND CONCLUSIONS

The resulting atlas consists of 109 anatomical slices and the corresponding 109 CT and 109 MR scans (altogether 327 images) and the nomenclature list for each image. Although this publication contains limited images of the resulted atlas, it is a reference source for anatomy education and clinical sciences. We are of the opinion that more comprehensive and especially online available interactive atlases should be prepared using similar methodology.