Computed Tomography and Cross‐sectional Anatomy of the Normal Dromedary Camel Tarsus (One Humped Camel)

The purpose of this study was to provide a detailed computed tomographic (CT) anatomic reference for the dromedary camel tarsus. Six cadaver pelvic limbs, obtained from three clinically and radiographically sound dromedary camels, were scanned in both soft tissue and bone windows starting from the calcaneal tuber towards the proximal metatarsus. Limbs were frozen at ?20°C and sectioned transversely via an electric bone saw. The CT images were evaluated and correlated with their corresponding cryosections. The resulting images provided detailed anatomic features for bones, joints and soft tissue components of the tarsus and are intended to serve as a basic reference for the CT scanning of the dromedary camel tarsal pathology.     

Anatomy of the Thorax Structures in a Newborn Dromedary Camel by Computed Tomography

The anatomical and clinical studies of computed tomography (CT) in Camelidae are scarce. The use of CT in large animal medicine is currently limited by the logistic problems of acquiring computed tomographic images. Several CT studies exist on adult llamas, but not in camels. Accurate interpretation of the planimetric CT normal anatomy is necessary for the study and evaluation of pathological tissues. The purpose of our work was to evaluate the thorax of the newborn camel and related structures by means of CT images and macroscopic sections. One newborn camel of one week was used. It was euthanized for medical reasons unrelated to disease of the thorax. CT images were obtained and detailed anatomy of the thorax was acquired. Different CT windows, soft‐tissue and pulmonary windows, were applied in order to obtain detailed attenuation shades of the thoracic structures. The camel was frozen and sectioned using an electric saw, and we obtained high quality images of the thorax compared with CT images. Clinically relevant anatomic structures of the thorax cavity were identified and labelled in the corresponding CT and gross‐section photographs. The information presented in this paper should serve as an initial reference to evaluate CT images of the newborn camel thorax.     

Temporo-spatial Expression of the Inducible Nos-isoform During Development of the Murine Enteric Nervous System

The anatomical and clinical studies of computed tomography (CT) in Camelidae are scarce. The use of CT in large animal medicine is currently limited by the logistic problems of acquiring computed tomographic images. Several CT studies exist on adult llamas, but not in camels. Accurate interpretation of the planimetric CT normal anatomy is necessary for the study and evaluation of pathological tissues. The purpose of our work was to evaluate the thorax of the newborn camel and related structures by means of CT images and macroscopic sections. One newborn camel of one week was used. It was euthanized for medical reasons unrelated to disease of the thorax. CT images were obtained and detailed anatomy of the thorax was acquired. Different CT windows, soft-tissue and pulmonary windows, were applied in order to obtain detailed attenuation shades of the thoracic structures. The camel was frozen and sectioned using an electric saw, and we obtained high quality images of the thorax compared with CT images. Clinically relevant anatomic structures of the thorax cavity were identified and labelled in the corresponding CT and gross-section photographs. The information presented in this paper should serve as an initial reference to evaluate CT images of the newborn camel thorax.     

Computed tomographic anatomy of the temporomandibular joint in the young horse

Reasons for performing study: The equine temporomandibular joint (TMJ) and its surrounding structures can be difficult to investigate in cases with a clinical problem related to the region. Little previous attention has been given either to a computed tomographic (CT) imaging protocol for the joint or an interpretation of the structures displayed in CT images of the normal joint. Objectives: To provide a CT atlas of the normal cross‐sectional anatomy of the equine TMJ using frozen and plastinated sections as anatomical reference. Methods: Eight TMJs from 4 immature pure‐bred Spanish horses were examined by helical CT. Scans were processed with a detailed algorithm to enhance bony and soft tissue. Transverse CT images were reformatted into sagittal and dorsal planes. Transverse, sagittal and dorsal cryosections were then obtained, photographed and plastinated. Relevant anatomic structures were identified in the CT images and corresponding anatomical sections. Results: In the CT images, a bone window provided excellent bone detail, however, the soft tissue components of the TMJ were not as well visualised using a soft tissue window. The articular cartilage was observed as a hyperattenuating stripe over the low attenuated subchondral bone and good delineation was obtained between cortex and medulla. The tympanic and petrous part of the temporal bone (middle and inner ear) and the temporohyoid joint were seen in close proximity to the TMJ. Conclusions: Helical CT provided excellent images of the TMJ bone components to characterise the CT anatomy of the normal joint. Potential relevance: Detailed information is provided that may be used as a reference by equine veterinarians for the CT investigation of the equine TMJ and serve to assist them in the diagnosis of disorders of the TMJ and related structures (middle and inner ear). The study was performed at an immature stage and further studies of mature individuals are required in order to confirm that the clinical interpretation is not affected by changes occurring with age.     

Comparative Evaluation of the Cadaveric and Computed Tomographic Features of the Coelomic Cavity in the Green Iguana (Iguana iguana), Black and White Tegu (Tupinambis merianae) and Bearded Dragon (Pogona vitticeps)

Contrast‐enhanced computed tomographic studies of the coelomic cavity in four green iguanas, four black and white tegus and four bearded dragons were performed using a conventional CT scanner. Anatomical reference cross sections were obtained from four green iguana, four black and white tegu and six bearded dragon cadavers; the specimens were stored in a ?20°C freezer for 24 h then sliced into 5‐mm intervals. The frozen sections were cleaned with water and photographed on both sides. The individual anatomical structures were identified by means of the available literature; these were labelled first on the anatomical images and then matched to the corresponding computed tomography images. The results provide an atlas of the normal cross‐sectional and computed tomographic anatomy of the coelomic cavity in the green iguana, the black and white tegu and the bearded dragon, which is useful in the interpretation of any imaging modality.     

Computed Tomography Atlas of the Normal Cranial Canine Abdominal Vasculature Enhanced by Dual‐phase Angiography

This study was performed to provide a detailed atlas of the normal arterial and venous canine vasculature in the cranial abdomen by dual‐phase computed tomographic angiography. Five adult beagles were positioned in dorsal recumbency on a multislice helical CT scanner. An unenhanced survey CT scan from the diaphragm to the pelvic inlet was performed. Bolus‐tracking software was used for the dual‐phase angiogram, and contrast medium was administered in a cephalic vein. The arterial phase was scanned from the mid‐abdomen to the cranial aspect of the diaphragm; the portal phase was scanned a few seconds after the arterial phase in the opposite direction. The DICOM studies from all dogs were analysed. Representative images were selected and anatomic structures labelled. Maximum intensity projections and three‐dimensional images were generated using software techniques. A detailed atlas of the venous and arterial vasculature of the cranial canine abdomen was created with the help of bolus‐tracking dual‐phase computed tomographic angiography (CTA). Practitioners can use this anatomic atlas with its detailed venous and arterial phase CT angiograms of the canine cranial abdomen to compare normal versus abnormal vascular anatomy.     

Computed tomographic and radiographic morphology of the pastern and coffin joints of One-Humped Camel (Camelus dromedarius)

The objective of the current study was to describe the structures of the pastern and coffin joints in dromedary camel using x-ray, bone and soft tissue windows computed tomography (CT) and three-dimensional volume rendering (3DVR) of CT imaging. 3DVR of CT was obtained at the slight flexed dorsal view, plantar view, dorsolateral view and lateral view which explained all the surfaces and structures of the digit bony parts even the parts of the articular surface. The processed images of 3DVR of CT showed different patterns of the cortical, cancellous, subchondral bones and medullary cavity of the bones of the digits. The present study showed clearly all the hard and soft tissues in the pastern and coffin joints of the camel in CT images; however, the plantar ligaments of the pastern joint and ligaments of the navicular cartilage identified on CT images. The CT soft tissue window visualized the joint cavity and their pouches and tendon sheath of the flexor tendons better than the bone window CT. The radiographic, CT and 3D images could be used as a normal reference for the interpretation of some clinical diseases in the pastern and coffin joints of the camel.     

Surgical anatomy of the nasal and paranasal sinuses in Egyptian native sheep (Ovis aries) using computed tomography and cross sectioning

The present work aimed to describe the normal computed tomography (CT) and cross‐sectional anatomy of the nasal and paranasal sinuses in sheep and to correlate these features with the relevant clinical practices. Twenty apparent healthy heads of Egyptian native breed of sheep (Baladi sheep) of both sexes were used for studying these sinuses. CT images and their closely identical cross sections of the same head were selected and serially labelled in a progression from the rostral nasal region to the caudal aspect of the head using cheek teeth as landmarks. The current investigation reported seven sinuses in sheep, including maxillary, frontal, lacrimal and sphenoidal as paranasal, as well as dorsal and middle conchal and ethmoidal as nasal with unnoticeable palatine and ventral nasal conchal sinuses. The boundaries, extension, structure and communications of these sinuses were fully described. The current study provided anatomical guidelines for surgical interference in the frontal and maxillary sinuses during trephination, dehorning and sinuscopy. Also, an acceptable anatomical explanation was reported in this study for the high incidence of maxillary sinusitis than other sinuses. CT and cross‐sectional anatomy could be used as helpful database for diagnosis and clinical interference of the nasal and paranasal sinuses in sheep.     

FEASIBILITY OF ULTRASOUND‐GUIDED EPIDURAL ACCESS AT THE LUMBO‐SACRAL SPACE IN DOGS

Epidural injections are commonly performed blindly in veterinary medicine. The aims of this study were to describe the lumbosacral ultrasonographic anatomy and to assess the feasibility of an ultrasound‐guided epidural injection technique in dogs. A cross sectional anatomic atlas of the lumbosacral region and ex vivo ultrasound images were obtained in two cadavers to describe the ultrasound anatomy and to identify the landmarks. Sixteen normal weight canine cadavers were used to establish two variations of the technique for direct ultrasound‐guided injection, using spinal needles or epidural catheters. The technique was finally performed in two normal weight cadavers, in two overweight cadavers and in five live dogs with radiographic abnormalities resulting of the lumbosacral spine. Contrast medium was injected and CT was used to assess the success of the injection. The anatomic landmarks to carry out the procedure were the seventh lumbar vertebra, the iliac wings, and the first sacral vertebra. The target for directing the needle was the trapezoid‐shaped echogenic zone between the contiguous articular facets of the lumbosacral vertebral canal visualized in a parasagittal plane. The spinal needle or epidural catheter was inserted in a 45° craniodorsal–caudoventral direction through the subcutaneous tissue and the interarcuate ligament until reaching the epidural space. CT examination confirmed the presence of contrast medium in the epidural space in 25/25 dogs, although a variable contamination of the subarachnoid space was also noted. Findings indicated that this ultrasound‐guided epidural injection technique is feasible for normal weight and overweight dogs, with and without radiographic abnormalities of the spine.     

Anatomy of the cranioencephalic structures of the camel (Camelus dromedarius L.) by imaging techniques: a magnetic resonance imaging study

The objective of this study was to define the anatomy of the cranioencephalic structures and associated formations in camel using magnetic resonance imaging (MRI). MR images were acquired in sagittal, transverse and oblique dorsal planes, using spin-echo techniques, a magnet of 1.5 T and a standard human body coil. MR images were compared with corresponding frozen cross-sections of the head. Different anatomic structures were identified and labelled at each level. The resulting images provided excellent soft tissue contrast and anatomic detail of the brain and associated structures of the camel head. Annotated MR images from this study are intended to be a reference for clinical imaging studies of the head of the dromedary camel.     

Magnetic Resonance Imaging and Cross Section Images of the Cat Thorax

Accurate interpretation of thoracic magnetic resonance images requires a thorough knowledge of anatomy of this region. The purpose of this communication is to describe the normal cross sectional anatomy of the thoracic cavity of the cat, using MR images, dissections and macroscopic sections. In this study, three cats were used. The animals were anesthetized and positioned in sternal recumbency in the MR scanner. MR imaging was performed at the Special Diagnostic Service of San Roque Clinic of Las Palmas de Gran Canaria with a superconducting magnet operating at a field strength of 1.5 Tesla and a human body coil. Spin echo pulse sequences were used to obtain T1-weighted images in tranverse and sagittal planes. At the conclusion of imaging, the cats were euthanatized for medical reasons unrelated to disease of thorax. The cats were frozen and then sectioned using an electric band saw. The cuts were matched as closely as possible to the MR images for identifying the normal planimetric anatomy of the thoracic structures. MR T1-weighted spin echo images provided excellent anatomic appearance of the thorax structures. In MR images the grey scale is directly related to the signal intensity of the thoracic cavity structures. Thus, fat and nerves had higher signal intensity compared with the lower signal intensity of the respiratory system. Bone marrow and muscles had a intermediate signal intensity and appeared gray. The intensity signal of the articular fluid permits a good differentiation of the opposing cartilage surfaces on all MR images. The planimetric or sectional anatomy of the thoracic cavity in the cat allows a correct morphologic and topographic evaluation of the anatomic structures, being helpful tool for the identification of the MR images. The information presented should serve as an initial reference to evaluate MR images of the feline thorax and to assist interpretation of lesions of this region.     

Normal anatomic reference of pastern and coffin joints in Egyptian buffalo (Bubalus bubalis): A compared atlas of cross-sectional anatomy,magnetic resonance imaging and computed tomography

The purpose of this study was to describe normal magnetic resonance imaging and computed tomographic anatomy of pastern and coffin joints in Egyptian buffalo using cadaveric distal limbs. This study was achieved using twelve fresh cadaveric distal limbs from adult healthy buffaloes of both sexes. These cadaveric limbs were scanned using a 1 Tesla MRI scanner and CT scanner, injected with red latex, frozen at −20°C for 1 week, and then sectioned into sagittal, dorsal and transverse slices. The obtained MR and CT images were selected to be matched with their corresponding anatomical cross-sections for identification and evaluation of the clinically correlated anatomical structures of the pastern and coffin joints. The difference in signal intensities on CT and MRI scans amongst the tissues allowed clear differentiation of major bone and soft tissue structures of the pastern and coffin joints. CT provided a high spatial resolution of bone and soft tissue structures, however, MRI allowed a better and higher resolution and definition between soft tissues. The current study provided a normal CT and MRI anatomic reference which could help veterinary clinicians for interpretation and diagnosis of the clinically affected pastern and coffin joints in buffalo.     

Normal Radiographic and Ultrasonographic Appearance of the Adult Dromedary Camel Tarsus (One Humped Camel)

Six cadaver pelvic limbs were obtained from clinically sound dromedary camels and examined radiographically and ultrasonographically using a 7.5 MHz convex transducer. Radiographic examination was performed in dorsoplantar, lateromedial, dorsolateral‐plantaromedial oblique and plantarolateral‐dorsomedial oblique projections, and the bony structures and articulations of the tarsal joint were outlined. The tarsus was ultrasonographically investigated in four planes (dorsal, medial, lateral and plantar), and each plane was scrutinized in four levels (calcaneal tuber, tibial malleoli, base of calcaneus and proximal end of metatarsus) in both transverse and longitudinal views. Limbs were examined grossly, frozen at ?20°C and sectioned. Radiographic and ultrasonographic findings correlated well with the gross anatomy and frozen sections. The normal appearance of bony and soft structures of the tarsus described in this study provided basic reference data for ultrasonographic and radiographic investigations of tarsal disorders in the dromedary camel.     

COMPUTED TOMOGRAPHIC ANATOMY OF THE EQUINE TARSUS

The purpose of this study was to provide a detailed computed tomographic (CT) anatomic reference for the equine tarsus. CT examinations of the tarsal regions from four clinically and radiographically normal adult horses, which were euthanized for reasons not related to musculoskeletal disease, were included in the study. Limbs were removed at the level of midtibia, and 3-mm contiguous transverse CT images were obtained, starting at a level proximal to the tuber calcanei and continuing distally into the proximal metatarsus. Soft tissue and bone windows were used to image different anatomic features, including bones, joints, and various soft tissue components of the tarsus. Each transverse slice was compared with bone models and dissected specimens to assist in the accurate identification of specific structures. The results of the study consist of nine CT images of the equine tarsus. Each image incorporates labeled soft tissue and bone-window images, a directional compass indicating cranial (Cr) or dorsal (D) and lateral (L), and a reconstructed scout image indicating the level through which the transverse slice was made.