THE NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE COCKATIEL (NYMPHZCUS HOLLANDZS)

The purpose of the study was to provide a reference for the normal radiographic anatomy of the cockatiel ( Nymphicus hollundis ). The head, body, wing, and pelvic limb of mature males were radiographed using xeroradiographic and conventional radiographic techniques. Ten xeroradiographs and ten corresponding conventional radiographs were selected, and the xeroradiographs appropriately labeled to illustrate the normal radiographic anatomy of these regions.     

THE NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE ORANGE-WINGED AMAZON PARROT (AMAZONA AMAZONICA AMAZONICA)

The purpose of the study was to provide a reference for xeroradiographic and conventional radio-graphic anatomy of the orange-winged Amazon parrot ( Amazona amazonica amazonica ) as a representative of medium-sized psittacine birds that are commonly kept as pets. The head, body, wing, and pelvic limb of a mature bird were radiographed using xeroradiographic and conventional radiographic techniques. Ten xeroradiographs and ten corresponding radiographs were selected, and the xeroradiographs labeled to illustrate the normal radiographic anatomy of these regions. Also included is a short discussion of unique avian anatomic features which are important to clinical evaluation.     

NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE MALLARD DUCK (ANAS PLATYRHYNCHOS) WITH REFERENCE TO OTHER ANSERINE SPECIES

The purpose of this study was to provide a reference for xeroradiographic and conventional radiographic anatomy of the mallard duck ( Anas platyrhynchos ) as a representative of the avian Order Anseriformes. The head, body, wing, and pelvic limb of three adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Nine xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate normal anatomy. Selected views of other anseriform species were included to illustrate certain anatomical features unique to those species.     

RADIOGRAPHIC ANATOMY OF THE CRIBRIFORM PLATE (LAMINA CRIBROSA)

The radiographic appearance of the cribriform plate was investigated in 16 canine cadaver heads. The cribriform plate appeared as a "V"-shaped multilinear bone-opaque stripe in the caudal nasal region in projections perpendicular to the hard palate in 6 dogs with a skull index between 50.00 and 54.00. In 9 dogs with a skull index between 55.40 and 74.40, the cribriform plate had a more "C"-shaped and sharp appearance. In vertically oblique projections with an obliquity greater than 20 degrees, the cribriform plate lost its sharp outline and finally (40 degrees) disappeared. In lateral projections the cribriform plate appeared as a "C"-shaped interrupted bone-opaque stripe in all 16 dogs. In more brachycephalic dogs frontal bone structures superimposed on the cribriform plate on ventrodorsal and dorsoventral views and accentuated the radiographic appearance of the plate. Vertically oblique views separated both structures to produce two lines.     

RADIOGRAPHIC APPEARANCE OF THE FEET OF MAMMOTH DONKEYS AND THE FINDING OF SUBCLINICAL LAMINITIS

All feet of 10 clinically sound mammoth donkeys (Group I) were radiographed to determine the appearance of the distal phalanx. The distal phalanges had blunted to concave-shaped dorsal solar margins which varied in appearance from slight to pronounced. The distal phalanges of the forefeet were wider than those of the hindfeet, and also were positioned a greater distance from the dorsal aspect of the hoof wall. The greater distance between the dorsal aspect of the hoof wall and the distal phalanges seemed related to the presence of a periosteal-like bony proliferation on the dorsum of the distal phalanx. This bony proliferation occurred in those distal phalanges which also had radiographic findings consistent with pedal osteitis. Next, all feet of 5 additional mammoth donkeys (Group II) that were to be necropsied for various reasons, were examined similarly to Group I, necropsied and found to have laminitis. Only 2 of these 5 donkeys had been lame; only one had rotation of the distal phalanges (in the forefeet). Radiographic data from the 4 donkeys without rotation seemed most similar to that found in those Group I donkeys which had periosteal reactions on their distal phalanges. Conclusions from this study were that: 1) feet of mammoth donkeys have some anatomic differences from those of domestic horses, 2) subclinical laminitis and pedal osteitis can occur in mammoth donkeys, 3) rotation of the distal phalanx occurs in some, but not all laminitic donkeys, 4) laminitic changes may be more pronounced in their fore than in their hindfeet, and 5) additional studies of donkeys need to be done, examining both proven normal and confirmed laminitic feet.     

NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE RED-TAILED HAWK (BUTEO JAMAICENCIS), WITH REFERENCE TO OTHER DIURNAL RAPTORS

The purpose of this study was to provide a reference for xeroradiographic and conventional radio-graphic anatomy of the red-tailed hawk (Buteo jamaicencis) as a representative of the avian Order Falconiformes. The head, body, wing, and pelvic limb of three adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Twelve xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate the normal anatomy of these regions.     

NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE BOBWHITE QUAIL (Colinus virginianus), WITH REFERENCE TO OTHER GALLIFORM SPECIES

The purpose of this study was to provide a reference for xeroradiographic and conventional radiographic anatomy of the bobwhite quail ( Colinus virginianus ) as a representative of the avian order Galliformes. The heads, bodies, wings, and pelvic limbs of four adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Nine xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate the normal anatomy of these regions. A xeroradiograph of the transometatarsus of the domestic peacock ( Pavo cristatus ) was also included to demonstrate the metatarsal spur, which is not present in the quail.     

RADIOGRAPHIC TECHNIQUE AND ANATOMY OF THE EQUINE SACROILIAC REGION

Radiography is part of evaluating horses with poor performance and pelvic limb lameness; however, the radiographic appearance of the sacroiliac region is poorly described. The goal of the present study was to describe the use of a simple technique to obtain radiographs of the sacroiliac region in the anesthetized horse and to describe the radiographic appearance of this region. Seventy-nine horses underwent radiography of the pelvis under general anesthesia in dorsal recumbency. During a 5s exposure time the horse was actively ventilated to blur the abdominal viscera, which allowed assessment of individual bone structures in 77 horses. A large variation in the shape of the sacral wings, their articulation with the transverse processes of L6, and the relation of the sacrum to the ilium were observed. Females had significantly narrower width of the sacral wings. Broad sacral wings and bony proliferations at the caudal aspect were commonly observed features and their size was highly correlated with gender. In males, caudal osteophytes were significantly larger than in females. Five horses had transitional or hemitransitional vertebrae. Radiography with the ventilation-induced blurring technique is a simple approach that results in diagnostic quality radiographs and delineation of the highly variable bone structures of the sacroiliac region.     

NORMAL XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE GREAT HORNED OWL (BUBO VIRGINIANUS), WITH SPECIAL REFERENCE TO THE BARN OWL (TYTO ALBA)

The purpose of this study was to provide a reference for xeroradiographic and conventional radiographic anatomy of the great horned owl ( Bubo virginianus ) as a representative of the avian Order Strigiformes. The head, body, wing, and pelvic limb of three adult birds were radiographed using xeroradiographic and conventional radiographic techniques. Twelve xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate normal anatomy. Selected views of the barn owl ( Tyto alba ) were included to illustrate significant differences between this and other species of owls.     

RADIOGRAPHIC DIAMETER OF THE COLON IN NORMAL AND CONSTIPATED CATS AND IN CATS WITH MEGACOLON

Radiographs of 50 cats with no history of gastrointestinal disease were evaluated to establish a normal reference range for radiographic diameter of the feline colon. Thirteen cats with constipation and 26 with megacolon were also evaluated and compared with the normal cats to characterize the accuracy of the reference range and to identify a cutoff to distinguish constipation from megacolon. A ratio of maximal diameter of the colon to L5 length was the most repeatable and accurate measurement. A ratio <1.28 is a strong indicator of a normal colon (sensitivity 96%, specificity 87%). A value >1.48 is a good indicator of megacolon (sensitivity 77%, specificity 85%).     

EPIDUROGRAPHY IN THE NORMAL DOG: TECHNIC AND RADIOGRAPHIC FINDINGS

Ten clinically normal adult mongrel dogs were examined using lumbosacral epidurography in an effort to determine a reproducible technic and a normal radiographic appearance. The site of contrast medium injection was the ventral epidural space at the sacrococcygeal junction or the cranial coccygeal region. An initial dose of 0.15 ml/kg of metrizamide for the right lateral recumbent radiograph with 0.10 ml/kg additional metrizamide for additional right lateral or the subsequent dorsoventral radiographs was considered adequate. Two numerical values were observed for each normal epidurogram: the sacrovertebral angle; the ratio of the contrast medium column width to L6 body length. A statistically significant relationship between hindlimb positioning and the numerical value of the sacrovertebral angle was identified. Some advantages of epidurography for delineating the lumbosacral area are obvious: (1) it overcomes the limited value of lumbosacral area myelography; (2) it is technically easier than intraosseous vertebral venography; (3) there is minimal patient trauma; (4) there was no apparent adverse sequela to repeated contrast medium injections.     

MAGNETIC RESONANCE IMAGING AND CROSS SECTIONAL ANATOMY OF THE NORMAL EQUINE SINUSES AND NASAL PASSAGES

The purpose of this investigation was to define the magnetic resonance imaging anatomy of the rostral part of the equine head. 10 mm-thick, T1-weighted images of two isolated equine cadaver heads were obtained using a 1.5 Tesla magnet and a body coil. MR images were compared to corresponding frozen cross-sections of the cadaver head. Relevant anatomic structures were identified and labeled at each level. The resulting images provided excellent anatomic detail of the oral and nasal cavities, paranasal sinuses and associated structures. Annotated MR images from this study are intended as a reference for clinical MR imaging studies of the equine head.     

XERORADIOGRAPHIC AND RADIOGRAPHIC ANATOMY OF THE CHANNEL CATFISH, ICTALURUS PUNCTATUS

The purpose of this study was to provide an anatomic reference for the channel catfish ( Ictalurus punctatus ) using xeroradiography * and conventional radiography. The entire body of three adult fish was radiographed using standard xeroradiographic and conventional radiographic techniques. Two xeroradiographs and their corresponding conventional radiographs were selected, and the xeroradiographs labeled to illustrate the normal skeletal and soft-tissue anatomy of the channel catfish.     

AN INNOVATIVE TECHNIQUE FOR DISPLAYING THREE DIMENSIONAL RADIOGRAPHIC ANATOMY OF SYNOVIAL STRUCTURES IN THE EQUINE DISTAL LIMB

Radiography is the most commonly applied imaging modality in equine practice and forms an essential part of the diagnostic work-up of lame horses. Radiographic signs of musculoskeletal pathology are frequently localized at sites of soft tissue attachment, which are often not clearly visible on radiographs. Different lesions carry different prognoses and require a variety of treatments, and a good knowledge of the position of the synovial structures in the distal limb of the horse is essential for practitioners in the interpretation of radiographs. This study describes a new technique for creating three-dimensional (3D) models of the synovial structures and superimposing them onto radiographs for the purpose of teaching radiographic anatomy. A set of standard radiographs was acquired of the metacarpophalangeal and the distal interphalangeal joints of a fresh cadaver leg while the leg was positioned in a material-testing machine to mimic the weight-bearing horse. Computed tomography of the same regions was performed after injection of negative contrast medium into the joints. 3D reconstructions of the joints were created using grayscale thresholding and polynomial surface meshing in Mimics. The resulting 3D reconstructions were superimposed on top of the radiographs using Adobe^© Photoshop^© CS3 Extended, thus allowing the visualization of the joint anatomy in relation to the bone on all projections. The main advantage of this technique is that it allows synovial structures to be visualized on radiographs where they are normally indistinct, which will serve as a teaching aid for anatomy.     

RADIOGRAPHIC CHANGES ASSOCIATED WITH DIGITAL, METACARPAL AND METATARSAL TUMORS, AND PODODERMATITIS IN THE DOG

Fifty-two of digital, metacarpal or metatarsal canine tumors and 48 pododermatitis lesions were reviewed retrospectively. The tumors were divided into 42 malignant neoplasms, 6 benign neoplasms and 4 non-neoplastic tumor-like growths. The distribution and radiographic changes of the lesions associated with the tumors and inflammation were compared. Pododermatitis and benign processes could not be radiographically differentiated from malignant neoplasms of the foot; however, lesions exhibiting osteolysis were more likely (p < 0.05) to be associated with malignant neoplasms.     

RADIOGRAPHIC ANATOMY AND BARIUM SULFATE CONTRAST TRANSIT TIME OF THE GASTROINTESTINAL TRACT OF BEARDED DRAGONS (Pogona vitticeps)

The positive contrast gastrointestinal study is a common non‐invasive diagnostic technique that does not require anesthesia and enables good visualization of the digestive tract. Radiographic anatomy and reference intervals for gastrointestinal contrast transit time in inland bearded dragons (Pogona vitticeps) were established using seven animals administered 15 ml/kg of a 35% w/v suspension of barium by esophageal gavage. Dorso‐ventral and lateral radiographic views were performed at 0, 15, 30 min, 1, 2, 4, 6, 8, 12 h, and then every 12 h up to 96 h after barium administration. Gastric emptying was complete at a median time of 10 h (range 4–24 h). Median jejunum and small intestinal emptying times were 1 h (range 30 min–2 h) and 29 h (range 24–48 h), respectively. Median transit time for cecum was 10 h (range 8–12 h). Median time for contrast to reach the colon was 31 h (range 12–72 h) after administration. Results were compared to those obtained in other reptilian species. This technique appeared safe in fasted bearded dragons and would be clinically applicable in other lizard species.     

DEVELOPMENT OF A WHOLE BODY MAGNETIC RESONANCE IMAGING PROTOCOL IN NORMAL DOGS AND CANINE CANCER PATIENTS

Whole body magnetic resonance imaging (whole body MR imaging) could potentially provide accurate cancer staging as a single imaging modality. This study was done to develop a whole body MR imaging protocol for a 1.5T MR instrument using four normal Beagle dogs (Phase 1) and then to assess the protocol's feasibility in cancer-bearing dogs (Phase II). In Phase I, anesthetized dogs were placed in dorsal recumbency with limbs flexed along the torso. T1, T2, and short tau inversion recovery sequences were acquired by spin echo or fast spin echo, and also using the more rapid single shot fast spin echo and gradient echo pulse sequences. Three large overlapping fields of view (FOV) were used to visualize the entire body and the sagittal and dorsal imaging planes were compared. Relative examination time, image quality, organ visibility and signal intensity were evaluated. Phase I results were used to establish a protocol that balanced image quality with examination time. In Phase II, whole body MR imaging was done on 10 dogs with cancer. Examination times were 60-75 min. Image quality was sufficient for all known lesions to be visualized, including mass lesions, pulmonary infiltrate, and lymphadenomegaly. Skeletal detail was sufficient to visualize known neoplastic lesions of the appendicular skeleton, yet it was suboptimal because of the large FOV and use of the body coil. Additional modifications of a whole body MR imaging protocol and continued technological improvements in MR imaging will further increase its potential for veterinary cancer staging.     

RADIOGRAPHIC ANATOMY OF THE CANINE COXOFEMORAL JOINT USING THE DORSAL ACETABULAR RIM (DAR) VIEW

A radiographic study of the anatomy of the canine acetabulum was performed. The relationship between the area of dorsal acetabular rim that is subject to early damage in dogs with coxofemoral joint laxity, and the "DAR point" identified on dorsal acetabular rim (DAR) radiographic views was examined. Radiographs and digital photographs were made of the pelvis harvested from each of six skeletally mature dogs. Through analysis of these images, it was determined that in the standing animal, the DAR point is located 4–6 mm (or approximately 37°) caudal to the dorsal acetabular rim area that is prone to early damage in dogs with coxofemoral joint laxity. This study suggests that the DAR radiographic view may under-represent changes to the dorsal acetabular rim in dogs with coxofemoral laxity.     

RADIOGRAPHIC AND MAGNETIC RESONANCE IMAGING OF THE STIFLE JOINT IN EXPERIMENTAL OSTEOARTHRITIS OF DOGS

Radiography and magnetic resonance imaging were used to evaluate osteoarthritis at 2, 6, and 12 weeks following transection of the cranial cruciate ligament of the stifle (femorotibial) joint of 6 dogs. A quantitative radiographic scoring system was used to assess the progression of hard and soft tissue changes of osteoarthritis. Mediolateral (flexed joint) and oblique (extended joint) radiographic projections enabled identification of small osteophytes on the femoral trochlear ridges, which were detected at an earlier stage of development than was previously reported. Magnetic resonance imaging was useful in detecting changes in cartilage thickness, osteophytosis and intraarticular loose bodies. Radiography and magnetic resonance imaging were complementary in the assessment of pathologic changes of osteoarthritis.