bluuebunny/crossref_metadata_2025 huggingface dataset:
DOPPLER ULTRASONOGRAPHIC DIAGNOSIS AND ANATOMY OF CONGENITAL INTRAHEPATIC ARTERIOPORTAL FISTULA IN A PUPPY
Authors: Szatmári Viktor , Németh Tibor , Kótai István , Vörös Kágroly , Sótonyi Péter
Published: May 2005

A dilated, tortuous blood vessel was identified sonographically in the right medial liver lobe in a puppy with severe ascites. This vessel was thought to represent the dilated right medial portal vein branch. Using pulsed wave Doppler ultrasonography, retrograde, abnormally pulsatile flow was detected in both the dilated right medial portal vein branch and the main portal vein. The right medial liver lobe was surgically resected then fixed in formalin. Silicon rubber was injected and outlined the connection between the portal vein and hepatic artery.
RADIOGRAPHIC AND ULTRASONOGRAPHIC EVALUATION OF THE NORMAL FELINE POSTPARTUM UTERUS
Authors: Ferretti Lisa M. , Newell Susan M. , Graham John P. , Roberts Gregory D.
Published: May 2005

The radiographic and ultrasonographic appearance of the normal involution process of the feline postpartum uterus has not been previously described. Six queens were examined to determine the normal radiographic and ultrasonographic appearance of the involuting postpartum uterus. Radiographic and ultrasonographic examinations were performed daily from days one through ten, then on days 12,14,18, 24, and 28 postpartum. Radiographically the mean total uterine thickness was 16.5 mm at day one postpartum. By day 14 the mean total uterine thickness was 10.5 mm and by day 24 postpartum the uterus was not radiographically visible. Ultrasonographically at day one postpartum the mean total uterine thickness was 16.6 mm and the mean uterine wall thickness was 2.7 mm. At day 14 postpartum the mean total uterine thickness was 6.2 mm and the mean wall thickness was 2.1 mm. At day 28 postpartum the uterus could still be identified ultrasonographically however individual wall layers were not discernable.
DYNAMIC CT MEASUREMENT OF CONTRAST MEDIUM WASHIN KINETICS IN CANINE NASAL TUMORS
Authors: Van Camp Sandy , Fisher Paul , Thrall Donald E.
Published: May 2005

Tumor oxygenation affects the biologic behavior of a tumor and also its radiation response. Decreased tumor oxygenation has been associated with an aggressive phenotype and with decreased local tumor control following irradiation. Thus, measurement of oxygenation may be useful for pretreatment evaluation of a tumor. Many methods for assessing tumor oxygenation are available but most are invasive. There is a need for a non‐invasive measure of oxygenation, or a surrogate for oxygenation. Measurement of perfusion has been suggested as a substitute for measurement of oxygenation. The use of washin kinetics of iodinated contrast medium to estimate perfusion has been shown to be related to radiation response of human carcinomas. We quantified the washin kinetics of iodinated contrast medium using dynamic CT in 9 dogs. All dogs had a malignant nasal tumor and perfusion was quantified at two sites in each tumor to evaluate intratumoral variation in perfusion. Dogs were given an intravenous bolus injection of contrast medium and arterial and tumor washin kinetics quantified using a helical CT scanner. Perfusion was estimated from these data using previously validated methods. Eight of the 9 dogs received definitive radiation therapy and perfusion was quantified a second time in these 8 dogs midway through irradiation. Pretreatment perfusion varied between dogs by a factor of 16.9. Between dog variation in perfusion was subjectively greater than within tumor variation based on comparison of two intratumoral regions. Changes in perfusion in individual dogs during irradiation were observed, but no identifiable pattern of perfusion alteration was detected. Measurement of perfusion in canine nasal tumors using dynamic CT is possible and further study of this parameter as it relates to radiation response is reasonable.
MAGNETIC RESONANCE IMAGING OF THE NORMAL AND DISEASED FELINE MIDDLE EAR
Authors: Allgoewer Ingrid , Lucas Susanne , Schmitz Stephan Albert
Published: May 2005

The magnetic resonance imaging appearance of the feline middle ear is described in three healthy cats and in five cats with middle ear disease. Owing to the good spatial resolution, multiplanar slice orientation as well as display high contrast resolution of soft tissue, in particular fluids, MR imaging was helpful prior to surgery. It is superior to radiography which failed to allow identification of the abnormality in two of our five cats. MR imaging for middle ear disease should include dorsal and transverse plane images using T1‐ and T2‐ weighted sequences. In the presence of a mass within the bulla or the external ear canal application of contrast medium is helpful.
BRONCHOCUTANEOUS FISTULA IN A DOG
Authors: Yamagishi Norio , Yamada Kazutaka , Ishikawa Hiroshi , Yamada Haruo
Published: May 2005

A dog with a bronchocutaneous fistula is described. Contrast enhanced computed tomography was useful for diagnosis and treatment of the fistula in this dog.
POST‐OPERATIVE COMPUTED TOMOGRAPHY IN TWO DOGS WITH CEREBRAL MENINGIOMA
Authors: Bergman Robert , Jones Jeryl , Lanz Otto , Inzana Karen , Shell Linda , Moon Martha , Wright R. Eric
Published: May 2005

Post‐operative computed tomography (CT) has been described as a technique for diagnosing incomplete resection or recurrence of cerebral neoplasms in humans. The characteristics of immediate postoperative CT images in dogs with intracranial pathology are unknown. This report describes findings from preoperative, immediate post‐operative, and 4 week to 9 month follow‐up CT examinations in two dogs with histologically‐confirmed cerebral meningiomas. In images of one dog after surgery there was mild contrast enhancement of the tissue surrounding the surgical site. This enhancement had resolved in later images and was probably the result of surgically induced trauma. In post operative images of the other dog there was significant hyperattenuation of the tissues around the surgical site. In post contrast images there was increased enhancement that was evident in later images. These findings, although not supported by necropsy, probably indicate incomplete excision of the tumor.
ALTERNATIVES FOR IMPROVING VETERINARY MEDICAL STUDENTS' LEARNING OF CLINICAL SONOGRAPHY
Authors: Wood Andrew K.W. , Lublin Jacqueline R. , Hoffmann Karon L. , Dadd Michael J.
Published: May 2005

With the widespread clinical use of sonography there is a need to introduce the topic into the curriculum. A new problem‐based course in clinical sonography without lectures was developed to emphasise experiential learning, and engage students actively in individual and collective acts of discovery. Four different approaches were used to deliver the new course to 141 veterinary medical students over four semesters. The physical principles of sonography were taught by computer‐assisted instruction and a practical class, clinical examinations were introduced during a session with a tutor, and finally each student wrote an essay on a sonographic topic of their choice. To evaluate the new course, students' responses to a questionnaire were analyzed. Students gained reasonable understanding of the physical principles of sonography and had some confidence in conducting a sonographic examination of an animal. Of most use to student learning was discussion with the teachers. Surprisingly, half the students thought the topic should also be taught by lectures. The students learned the material and acquired the sonographic skills through processes which required more independence and self‐responsibility than traditional teaching methods. The teachers' interaction with students on an individual basis, as they encountered individual problems, was the most important resource in learning about sonography. The continued request for lectures suggests an insecurity in some students caught between two different paradigms of teaching and learning (experiential, problem‐based learning versus lectures).
RELEVANCE OF SONOGRAPHIC ARTIFACTS OBSERVED DURINGIN VITROCHARACTERIZATION OF UROCYSTOLITH MINERAL COMPOSITION
Authors: Weichselbaum Ralph C. , Feeney Daniel A. , Jessen Carl R. , Osborne Carl A. , Dreytser V. , Holte J.
Published: May 2005

Nine pure mineral type canine uroliths (bladder or urethral origin only) were imaged ultrasonographically using 3.5 MHz, 5.0 MHz, and 7.5 MHz fixed focus, mechanical sector transducers in a urinary bladder phantom. The uroliths studied were those composed of 100% magnesium ammonium phosphate, calcium oxalate monohydrate, calcium oxalate dihydrate, calcium phosphate appatite, and calcium hydrogen phosphate dihydrate (brushite), ammonium acid urate, sodium acid urate, cystine, and silica. The occurrence of both reverberation/streak and acoustic shadowing artifacts were compared to urocystolith mineral type (classified by effective atomic number), urocystolith width, urocystolith height (thickness), and ultrasonographic imaging frequency. No predictable relationship was found between either of the artifacts seen beyond the urocystolith (reverberation/streak or the acoustic shadowing) and urocystolith mineral type. There was no statistical relationship between the occurrence of reverberation/streak artifact and the size (width or height) of the urocystolith or the ultrasonographic frequency. There was, however, a statistically relevant relationship.between ultrasonographic imaging frequency and the occurrence of acoustic shadowing and between urocystolith height (thickness) and the occurrence of acoustic shadowing. However, regardless of ultrasound frequency, acoustic shadowing was observed less than 35% of the time in any of the urocystolith mineral types examined. Based on the imaging of the bladder phantom supporting apparatus (7.0 mm bolts covered by plastic), the accurate characterization of a curved object surface directly facing the transducer was found to be directly related to the frequency of sound used for imaging and at best predictably limited to curved vs flat. Accurate measurement of the maximum transverse dimension of an echogenic curved object or accurate characterization of the lateral borders of such an object was considered unlikely with general ultrasonographic equipment of the frequencies studied. Therefore, detailed architectural characterization of urocystoliths suitable for mineral composition prediction is considered highly unlikely with general pulse‐echo ultrasonographic techniques.
ULTRASOUND EVALUATION OF THE PARATHYROID GLANDS IN TWO HYPERCALCEMIC CATS
Authors: Sueda T. , Stefanacci Joseph D.
Published: May 2005

Two parathyroid masses were identified using ultrasound in two hypercalcemic cats. The masses were identified as parathyroid adenomas on surgical biopsy. Both parathyroid masses contained hypoechoic regions with distal acoustic enhancement, Both masses were greater than 1.0 cm in diameter.
M‐MODE AND DOPPLER ECHOCARDIOGRAPHIC FINDINGS IN NORMAL FERRETS SEDATED WITH KETAMINE HYDROCHLORIDE AND MIDAZOLAM
Authors: Stepien Rebecca L. , Benson Keith G. , Wenholz Lisa J.
Published: May 2005

M‐mode and Doppler echocardiographic values were obtained from 30 normal adult ferrets (14 neutered females, 13 neutered males, 3 intact males) sedated with an intramuscular combination of keta mine hydrochloride and midazolam. Routine M‐mode measurements of the left and right ventricle, left atrium (LA) and aorta (AO) and Doppler measurements of aortic and pulmonic outflow, and mitral inflow were recorded. The following values were calculated: LA:AO diameter, ratio of peak E: peak A wave velocity (E:A ratio) for mitral inflow, and stroke volume (SV), cardiac output (CO) and cardiac index (CI) for both pulmonary and aortic outflow tracts. Maximal aortic velocities (AOmax) and velocity‐time integral values (A0 VTI) were significantly less than corresponding pulmonary outflow tract values (PAmaxPA VTI) but there was no difference in calculated values for SV, CO or CI. Calculated CO values were in the range expected based on the size of the species. Difficulties in aligning the aortic outflow tract for Doppler imaging may make pulmonary outflow Doppler values more consistent for use in estimating volume flow in ferrets.
ULTRASONOGRAPHIC EVALUATION OF TARSOCRURAL JOINT CARTILAGE IN NORMAL ADULT HORSES
Authors: Tomlinson Julia E. , Redding W. Rich , Sage Abby
Published: May 2005

Ultrasonographic examination of the tarsus was performed on four clinically and radiographically normal limbs of adult horses. Particular attention was paid to the articular cartilage surfaces of the trochlear ridges of the talus and the distal intermediate ridge of the tibia. Two separate measurements of articular cartilage thickness were acquired from a longitudinal view at each site. Anatomy was confirmed with post mortem dissection. Ultrasonography was found to be a practical method for imaging the articular cartilage over the trochlear ridges of the talus and distal intermediate ridge of the tibia. The cartilage appeared as a hypoechoic band overlying the hyperechoic subchondral bone. The mean cartilage thickness over the lateral and medial trochlear ridges of the talus and the distal intermediate ridge of the tibia were 0.57 mm, 0.58 mm and 0.7 mm respectively. These measurements may have value for comparison to thickened cartilage and lesions of osteochondrosis and abnormally thinned cartilage of osteoarthritis. Ultrasound examination was not helpful in evaluating the proximal and distal intertarsal and tarsometatarsal joints, the close proximity of the articular surfaces obscured visualization of the articular cartilage.
DOHUBLE‐PHASE PARATHYROID SCINTIGRAPHY IN DOGS USING TECHNETIUM‐99M‐SESTAMIBI
Authors: Matwichuk Cary L. , Taylor Susan M. , Daniel Gregory B. , Wilkinson A.A , Matte Gilbert G. , Dudzic E.M. , Shmon Cindy L.
Published: May 2005

The purpose of this study was to evaluate the utility of double‐phase parathyroid scintigraphy using 99mTc‐sestamibi for detecting and localizing hyperfunctioning parathyroid glands in hypercalcemic dogs. Fifteen hypercalcemic dogs that underwent parathyroid scintigraphy were included in this study: 3 dogs with hypercalcemia of malignancy, and 12 dogs with hyperfunctioning parathyroid tissue (parathyroid adenoma or parathyroid hyperplasia). The presence of parathyroid adenoma or parathyroid hyperplasia was documented by histopathologic examination. In 3 dogs with hypercalcemia of malignancy, parathyroid scintigraphy was negative for hyperfunctioning parathyroid tissue and the scans were classified as true negative. Parathyroid scintigraphy correctly identified the presence and location of hyperfunctioning parathyroid tissue in only 1 of 6 dogs with a parathyroid adenoma. False positive and false negative results occurred in dogs with parathyroid adenomas. Parathyroid scintigraphy failed to detect hyperfunctioning parathyroid tissue in 5 of 6 dogs with parathyroid hyperplasia and were classified as false negative. False positive results were obtained in the remaining dog with parathyroid hyperplasia. Sensitivity of parathyroid scintigraphy for detecting and localizing hyperfunctioning parathyroid tissue was 11%, specificity was 50%, and overall accuracy was 27%. Positive and negative predictive value were 25% and 27%, respectively. Sensitivity for detection of parathyroid adenomas was 25%, and sensitivity for detection of hyperplastic glands was 0%. Results of this study indicate that double‐phase parathyroid scintigraphy does not appear to have acceptable accuracy in detecting hyperfunctioning parathyroid glands in dogs. Due to the poor sensitivity and specificity of the technique in dogs, parathyroid scintigraphy is not recommended for definitive identification of abnormal parathyroid glands as the cause of hypercalcemia in dogs.
COMPARISON OF TWO PALPATION, FOUR RADIOGRAPHIC AND THREE ULTRASOUND METHODS FOR EARLY DETECTION OF MILD TO MODERATE CANINE HIP DYSPLASIA
Authors: Adams William M. , Dueland R. Tass , Daniels Ruth , Fialkowski James P. , Nordheim Erik V.
Published: May 2005

Hip joint laxity was evaluated in Golden Retriever (n = 60), Labrador Retriever (n = 23), and Labrador/ Golden Retriever mix (n = 24) puppies. Ortolani and Bardens maneuvers, four radiographic measurement indices and three dynamic ultrasonographic measurements were used. Each puppy was evaluated twice; at 6.5 to 9 and 43 to 79 weeks of age. These nine methods were compared for accuracy in predicting the development of canine hip dysplasia with or without degenerative joint disease by a median age of 16 months.

The Bardens maneuver was a significant predictor of canine hip dysplasia/±degenerative joint disease for Golden Retriever puppies, however, it was not a reliable predictor for the other two breeds. Norberg angle measurements taken with femurs in a neutral position with hips distracted (PennHip position) was a significant predictor of degenerative joint disease in two breeds, but not in Golden Retriever puppies. Ultrasound measurement was a reliable predictor of hip canine hip dysplasia//±degenerative joint disease for Labrador/Golden Retriever mix puppies, but was not reliable for the other two breeds. Palpation, radiographic, and ultrasonographic methods of evaluating hip joint laxity in puppies at 6.5 to 9 weeks of age were not consistently reliable for all three breeds in predicting hip dysplasia with or without degenerative joint disease at one year of age. A strong association was found between Norberg angle and degenerative joint disease occurrence, as well as between distraction index (PennHip) and degenerative joint disease occurrence when measured at 52 to 79 weeks of age, but not when measured at 6.5 to 9 weeks of age in these breeds. These results emphasize the difficulty of early detection of mild hip dysplasia in the dog.
COMPUTED TOMOGRAPHIC IMAGING OF THE EQUINE HEAD
Authors: Morrow Karen L. , Park Richard D. , Spurgeon Thomas L. , Stashak Ted S. , Arceneaux Billie
Published: May 2005

The head from three horses euthanized due to diseases unrelated to the head and neck was imaged using computed tomography (CT). Gross cross‐sectional slices of equine head #1 and skeleton of equine head #2 were compared with the CT images of the three equine heads to identify normal structures of the cranium, brain, paranasal sinuses, nasal cavity, and teeth. Labeled transverse CT images of the equine head are presented sequentially as a reference for normal anatomy.
DIAGNOSTIC IMAGING IN CANINE PHEOCHROMOCYTOMA
Authors: Rosenstein Diana S.
Published: May 2005

The diagnosis of pheochromocytoma is challenging due to the variable presentations of patients affected ith this neoplasm. This report describes four dogs with pheochromocytoma in which radiography, ultrasonography and computed tomography (CT) were key diagnostic tools. Computed tomography was the most useful imaging modality for assessment of size, shape and margination of the tumor. CT findings for the pheochromocytoma included a large, irregularly shaped mass in the dorsal midabdomen with multiple foci of low attenuation dispersed in hyperdense, highly vascular tissue. This neoplasm often invades the caudal vena cava and other surrounding organs therefore, although a pheochromocytoma may be identified in the absence of clinical signs, it should not be considered an incidental lesion. The unpredictable growth rate and potential for invasion of major vessels warrants serious consideration. Follow‐up ultrasound and CT examinations are recommended for patients with adrenal masses that do not undergo surgical excision.
THE COMPUTED TOMOGRAPHIC ENHANCEMENT PATTERN OF THE NORMAL CANINE PITUITARY GLAND
Authors: Love Nancy E. , Fisher Paul , Hudson Lola
Published: May 2005

Dynamic computed tomography (CT) of the pituitary gland was performed on four healthy male dogs of similar size, weight and age. The pituitary gland region was first identified on lateral scout and transverse non‐contrast images. After localization, water soluble iodinated contrast medium was ad‐ ministered intravenously as a bolus at a dose of 1 m1/lb using a pressure injector at an injection rate of 10 ml/sec and a total of 40 post contrast images of the pitutary gland were acquired. No images were made after 400 seconds. The same pituitary region was imaged in each slice. The slice thickness was 1.5 mm, with a two second scan time and an eight second delay between images (resulting in images every ten seconds). The contrast medium injection and initial image were acquired simultaneously, resulting in a non‐contrast enhanced initial image, At the completion of the CT scan, a region of interest (ROI) was drawn around the pituitary gland and time density data were obtained. The mean pituitary Hounsfield number was plotted as a function of time. A bi‐exponential least squares model was used to derive the best fitting line through the data. The mean relative peak increase in pituitary Hounsfield Units (HU) was 65.9%± 2.1%. After the initial increase there was a decrease in pituitary Hounsfield number with a half‐time of 16.1 seconds, followed by a slower phase with a half‐time of 16.5 minutes. The mean pituitary gland HU value during the period of gradual opacity decline was 35.0%± 4.4% above that of the pre‐contrast image.

Establishing the enhancement pattern in the canine pituitary gland is the precursor to the clinical application of dynamic CT of the pituitary gland to diagnose pituitary microadenomas and/or small macroadenomas before they become exceptionally large.
RADIOGRAPHIC DIAGNOSIS OF LAMENESS IN AFRICAN ELEPHANTS (LOXODONTA AFRICANA)
Authors: Hittmair Katharina M. , Vielgrader Hanna D.
Published: May 2005

Lameness in captive elephants is most commonly caused by pododermatitis or degenerative joint disease. Hard surfaces such as concrete, which produce a damp and cold environment, wet and muddy conditions, as well as restricted movement are the major causes of these problems. Radiography was performed in two African elephants at the Schoenbrunn Zoo in Vienna to determine the cause and extent of lameness. Various radiographic techniques are described for use in trained elephants. Low time settings were used to avoid loss of detail through movement and to minimize exposure while observing radiation safety. A 37‐year‐old elephant had front limb lameness due to an interdigital abscess. In radiographs of the foot an inhomogenous soft‐tissue swelling without involvement of the phalanges was seen. Ultrasonography was helpful in visualizing the fluid‐filled abscess. In additional joint radiographs severe degenerative joint disease was identified. A 13‐year‐old elephant had lameness of the hind limb. Radiographs of the hind limb from the foot to the stifle were made. Open physes and early signs of degenerative joint disease were identified on the radiographs.
DORSAL DENS ANGULATION AND A CHIARI TYPE MALFORMATION IN A CAVALIER KING CHARLES SPANIEL
Authors: Bynevelt Michael , Rusbridge Clare , Britton Juliet
Published: May 2005

A nineteen month old Cavalier King Charles had clinical signs consistent with a cervical myelopathy. Radiologically there was abnormal angulation of the dens with cervical spinal cord compression and a Chiari type malformation of the atlanto occipital region. The condition and method of investigation is discussed.
ULTRASONOGRAPHIC DIAGNOSIS: CRANIAL VENA CAVA THROMBOSIS IN A COW
Authors: Bueno Aloisio C.D. , Watrous Barbara J. , Parker Jill E. , Hedstrom Olaf R.
Published: May 2005

A 5‐year‐old Hereford cow was donated to Oregon State University, College of Veterinary Medicine. Two weeks before presentation the cow was treated by a left‐flank laparotomy to correct a uterine torsion that revealed an excessive amount of abdominal fluid and a full term dead fetus. Ultrasonographic evaluation of the right cranioventral thoracic cavity was performed owing to physical examination (muffled heart sounds, areas of silence) and thoracocentesis findings suggestive of pleuritis. Ultrasonography revealed hypoechoic pleural effusion and a mass of mixed echogenicity visible within the right atrial lumen extending into the cranial vena cava. A diagnosis of cranial vena cava thrombosis was demonstrated at necropsy. The clinical, ultrasonographic, and pathological features of this less common condition (cranial vena cava thrombosis) in cattle are discussed.
RESULTS OF IRRADIATION OF INFILTRATIVE LIPOMA IN 13 DOGS
Authors: McEntee Margaret C. , Page Rodney L. , Mauldin G. Neal , Thrall Donald E.
Published: May 2005

Thirteen dogs with infiltrative lipomas were treated with cobalt 60 radiation. Four of the thirteen dogs also received either whole body (n = 2) or combination local/whole body (n = 2) hyperthermia in conjunction with radiation therapy. Cytoreductive surgery was performed prior to radiation in 10 dogs, although only 3 dogs had microscopic disease at the time of radiation therapy. Dogs received a total dose of 45.6 Gy–63 Gy in 2.5–4 Gy/fraction on either a Monday/Wednesday/Friday schedule or on a daily Monday through Friday schedule. Twelve of the 13 dogs had computed tomography (CT) images acquired prior to irradiation. Survival time was determined from the time of completion of radiation therapy. Survival ranged from 6 months to 94 months, with a median (95% confidence interval) of 40 (18.5–77) months and a mean of 46.4 months. Only one dog was euthanized due to persistent signs related to the infiltrative lipoma at 6 months after the end of radiation therapy. There was no apparent difference in response based on whether or not the dogs received hyperthermia in conjunction with irradiation, although the numbers were too small to make any significant conclusions. It appears that dogs with infiltrative lipomas can benefit from external beam irradiation alone or in combination with surgery to effect long‐term local tumor control.
MAGNETIC RESONANCE IMAGING FEATURES OF BRAIN STEM ABSCESSATION IN TWO CATS
Authors: Klopp Lisa S. , Hathcock John T. , Sorjonen Donald C.
Published: May 2005

Premortem magnetic resonance imaging (MRI) was performed in two cats with brain stem abscessation confirmed post mortem by histology and recovery of multiple bacterial species. The MRI features of the abscesses were distinctive and included a thick and marked enhancement of the abscess capsule and extension of the lesion from a tympanic bulla in one cat. A focal area of increased signal intensity was present on T2‐weighted images. A circumscribed area of decreased signal intensity was surrounded by a ring of increased signal intensity on precontrast Tl‐weighted images. A center of decreased signal intensity with a thick, markedly enhanced abscess capsule was observed on post contrast Tl‐weighted images. These findings are compared to the current experimental and clinical literature of brain abscess. The underlying pathogenesis of MRI features is reviewed.
COMPARISON OF FAST SPIN‐ECHO AND CONVENTIONAL SPIN‐ECHO MAGNETIC RESONANCE SPINAL IMAGING TECHNIQUES IN FOUR NORMAL DOGS
Authors: Miyabayashi Takayoshi , Smith Mark , Tsuruno Yoshihiro
Published: May 2005

Various magnetic resonance (MR) imaging techniques have been used to assess lumbar spinal abnormalities in people. Four, young adult, clinically normal dogs were used to compare images of the spinal cord acquired using conventional spin‐echo and rapid acquisition relaxation‐enhanced (RARE), commonly called fast spin‐echo (FSE), magnetic resonance imaging techniques. Lateral myelograms were made as an anatomic control. The T2‐weighted FSE technique was characterized by better image quality than the T2‐weighted conventional spin‐echo technique. The short acquisition time with the FSE technique allowed increases in the matrix size and number of excitations, thus improving resolution and signal‐to‐noise ratio. In canine lumbar spinal MR imaging, use of a FSE technique is recommended to reduce the overall time for imaging and to improve image quality.
MAGNETIC RESONANCE IMAGING AND CROSS SECTIONAL ANATOMY OF THE NORMAL EQUINE SINUSES AND NASAL PASSAGES
Authors: Arencibia Alberto , Vázquez Jose M. , Jaber Raduán , Gil Francisco , Ramiírez Juan A. , Rivero Miguel , González Nelson , Wisner Erik R.
Published: May 2005

The purpose of this investigation was to define the magnetic resonance imaging anatomy of the rostral part of the equine head. 10 mm‐thick, Tl‐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.
RADIOGRAPHIC AND ECHOCARDIOGRAPHIC MEASUREMENT OF THE HEART IN OBESE CATS
Authors: Litster Annette L. , Buchanan James W.
Published: May 2005

A prospective study was undertaken to reconcile radiographic cardiomegaly and normal echocardiography in obese cats and to test a radiographic technique for better distinguishing between pericardial fat and the heart. Ten obese, but otherwise normal cats and 10 non‐obese normal cats were used. A body condition scoring system was used to objectively group obese and non‐obese normal cats. Two dimensional echocardiograms were made to verify that all cats had a normal heart. Thoracic radiographs then were made using standard and altered exposure techniques. The hearts were measured on these radiographs using the metric and a vertebral scale system. Obese cats consistently had excessive fat around the heart especially if they also had a large amount of falciform fat. Altering exposure technique by increasing mAs and decreasing kVp sometimes enhanced the radiographic contrast between fat and myocardium. Enhanced radiographic contrast accentuated the double silhouette identifying the true cardiac silhouette within the fat expanded silhouette. Pericardial fat usually was distinguished more readily in lateral than in VD radiographs. In two cats, pericardial fat had a characteristic prominent square corner to the right cranial margin of the cardiac silhouette in VD radiographs. Obesity caused increased width and depth of the thoracic cage. 2D echocardiograms revealed normal cardiac dimensions in both groups of cats and increased precordial distance in the obese group.
IMAGING OF A CAT WITH PERIRENAL PSEUDOCYSTS
Authors: Essman Stephanie C. , Drost Wm Tod , Hoover John P. , Lemire Tanya D. , Chalman James A.
Published: May 2005

A 16‐year‐old, neutered male, domestic short hair cat had abdominal distension and systemic hypertension. Radiography, ultrasonography, excretory urography, and renal scintigraphy were performed to establish the diagnosis and implement appropriate treatment. Bilateral perirenal pseudocysts were confirmed surgically and histopathologically. Following bilateral renal capsulectomy, systemic hypertension decreased and global glomerular filtration rate improved to normal limits. Multiple imaging modalities helped establish the diagnosis and guided implementation of appropriate treatment.
NODULAR FAT NECROSIS IN THE FELINE AND CANINE ABDOMEN
Authors: Schwarz Tobias , Morandi Federica , Gnudi Giacomo , Wisner Erik , Paterson Calum , Sullivan Martin , Johnston Pamela
Published: May 2005

The radiographic appearance of nodular fat necrosis is described in ten cats and one dog. The most common radiographic sign was the presence of a focal mineralized circular to oval soft tissue mass in the abdominal fat as present in 9 cats. These masses had a distinct eggshell‐like rim encapsulating the lesion. In one cat and one dog multiple masses were present, without radiographic signs of mineralization. Abdominal ultrasound was performed in three cats and one dog, findings included the presence of hyperechoic masses with associated acoustic shadowing, some with a hypoechoic centre. Almost all animals were old and obese. In three cats and one dog, changes were confirmed with biopsy or post mortem examination. Lesions having the appearance of those in this paper are most likely incidental findings and should not be confused with abdominal masses of neoplastic origin. Ultrasound can be helpful in identifying such lesions.
RETROSPECTIVE REVIEW OF THE ULTRASONOGRAPHIC FEATURES OF ADRENAL LESIONS IN 21 FERRETS
Authors: Besso Juliette G. , Tidwell Amy S. , Gliatto John M.
Published: May 2005

A review of ultrasonographic findings in 21 ferrets with confirmed adrenal lesions was performed. Clinical signs and follow‐up information were recorded. Histopathologic diagnoses were obtained for 25 adrenal glands in 21 ferrets. Adrenal lesions included ten adenocarcinomas, nine adenomas, one hyperplasia and one cortical cyst. Four adrenal glands (all right‐sided) were diagnosed as unspecified adrenal tumors but lacked a definite histopathologic diagnosis (adenoma vs. adenocarcinoma) due to incomplete surgical resection and consequent small sample sizes. Bilateral adrenal lesions were identified in 4 ferrets (19%). Adrenal shape, size, echogenicity, laterality, and the presence of vascular invasion were evaluated with ultrasound. Size and shape were variable and not specific to lesion type. Both benign and malignant adrenal tumors (adenomas, adenocarcinomas) appeared most often as masses with increased thickness and a normal length (11/23), less frequently as larger masses with increased thickness and length (4/23) or as nodules focally deforming the normal adrenal shape (6/23). The only cortical cyst appeared as a nodule. Three adrenal glands had a normal size and shape and were diagnosed as adenomas (2) or hyperplasia (1). Therefore treatment may be warranted based solely on clinical signs if adrenal glands are ultrasonographically normal. Vascular invasion was not identified ultrasonographically. However, focal absence of periglandular fat resulting in contact of 8 adrenal glands with either caudal vena cava (6), aorta (1) or liver (1) identified ultrasonographically, correlated with incomplete surgical resectability (6/8) and histopathologic diagnoses of carcinoma (4/8) or unspecified tumors (4/8). Therefore, a focal absence of periglandular fat between the adrenal gland and the large vessels or liver, deviation or compression of the large vessels by the adrenal lesion may indicate malignancy. Adrenal tumors (benign and malignant) were often associated with a prominent uterus, uterine stump or prostate with or without prostatic cysts.
SCINTIGRAPHIC DETECTION OF EQUINE ORTHOPEDIC INFECTION USING Tc‐HMPAO LABELED LEUKOCYTES IN 14 HORSES
Authors: Long Craig D. , Galuppo Larry D. , Waters Ned K. , Hornof William J.
Published: May 2005

The aim of this study was to evaluate the diagnostic value of99mTc‐HMPAO leukocyte scintigraphy (LS) by means of a retrospective review of its use in 14 horses that were evaluated for orthopedic infection as a cause of lameness. A total of 17 LS exams were performed in 14 horses. LS studies were positive in 10 of 14 horses. A bacterial infection was confirmed with cytology or culture in 9 of 10 positive horses. Negative LS studies occurred in 4 of 14 horses. Necropsy confirmed the lack of infection in 2 of the 4 horses. Other clinical data and a favorable clinical outcome supported a negative study in the other 2 horses. No false negative or false positive studies were identified. It may be concluded that HMPAO‐LS is an effective tool for the diagnosis of orthopedic infection in horses.
THE APPLICATION OF TECHNETIUM‐99m HEXAMETHYLPROPYLENEAMINE OXIME (99mTc‐HMPAO) LABELED WHITE BLOOD CELLS FOR THE DIAGNOSIS OF RIGHT DORSAL ULCERATIVE COLITIS IN TWO HORSES
Authors: East Leslie M. , Trumble Troy N. , Steyn Phillip F. , Savage Catherine J. , Dickinson Charles E. , Traub‐Dargatz Josie L.
Published: May 2005

The application of99mTc‐HMPAO labeled white blood cells to support the diagnosis of right dorsal ulcerative colitis was studied in two horses with a history and clinical signs consistent with phenylbutazone toxicity. These images were compared to a reference horse unaffected by right dorsal ulcerative colitis. Blood was collected aseptically in heparinized syringes from the patients for in vitro white blood cell (WBC) radiolabeling. The buffy coat was separated out and radiolabeled with99mTcHMPAO. The radiolabeled blood was re‐injected IV and four images of the right and left side of the patient's abdomen were acquired at 4 hours and 20 hours post‐injection. Results of the nuclear study revealed no abnormal findings in the abdomen at the four‐hour post‐injection images in any horse. Images obtained 20 hours post‐injection revealed a linear uptake of radiolabeled WBCs in the right cranioventral abdomen in the region of the right dorsal colon in both horses with right dorsal ulcerative colitis. The reference horse had no radiopharmaceutical uptake in this region. This nuclear imaging study was a rapid, non‐invasive method to identify right dorsal colon inflammation. These findings not only supported the diagnosis of right dorsal ulcerative colitis, but also facilitated appropriate medical management of each horse.
EFFECTS OF A DIGITAL FILTER ON DETECTABILITY OF A PHANTOM LESION IN A SCINTIGRAM OF THE EQUINE TARSUS
Authors: Eksell Per , Carlsson Sten , Lord Peter , Carlsten Johan
Published: May 2005

The aim of this study was to examine the effects of a digital filter on the detectability of a phantom lesion in a scintigram of the equine tarsus. Lateral images containing 50,100,150, 500, or 1000 kcounts were acquired. A created phantom lesion of 0 (normal), 10,15,20, or 30% increased intensity relative to local background was placed in the centrodistal tarsal joint area in the images of different count levels. Duplicate images were filtered with a Metz filter. The complete set of filtered and unfiltered images totaling 180 images was projected as slides to a group of 9 observers. The sensitivity in 50 and 100 kcount images was improved by applying the filter. Digital filtering increased the false positive fraction at all count levels but this effect was most pronounced in 500 and 1000 kcount images. Based on receiver operating characteristic analysis, filtering of a 50 kcount image improved image quality to that of a 150 kcount image.
MAGNETIZATION TRANSFER IMAGING OF THE CANINE BRAIN: A REVIEW
Authors: Vite Charles H. , McGowan Joseph C.
Published: May 2005

Magnetization transfer imaging is a modality capable of examining the non‐water components of brain tissue by examining the effects they have on water protons. It may be used qualitatively to increase the visibility of lesions seen during magnetic resonance angiography and following the administration of an intravenous paramagnetic contrast medium. Quantitatively, it can be used to examine the effect of pathology on magnetization transfer contrast, to provide a measurement of myelination, as well as to quantify disease progression in trauma, neoplasia, neurodegeneration and other disorders of the brain. This paper reviews the theory of magnetization transfer imaging, its applications, and provides an example of its use in examining the canine brain.
MR IMAGING FINDINGS IN A DOG WITH LUMBAR GANGLION CYSTS
Authors: Webb Aubrey A. , Pharr John W. , Lew Linda J. , Tryon Kimberly A.
Published: May 2005

Intraspinal cysts of the L6‐L7 and L7‐S1 articular process joints in a six‐year‐old neutered female German Shepherd Dog were diagnosed using magnetic resonance (MR) imaging. Histopathology provided a diagnosis of ganglion cysts. Clinical, laboratory, radiographic and MR imaging findings are described. Briefly, radiographic findings revealed lumbarization of the first sacral vertebra, and fusion of the first caudal vertebra to the sacrum. In addition, spondylosis and articular process osteoarthrosis occurred at L6‐L7 and L7‐S1. MR imaging revealed multiple, well encapsulated structures ranging in size from 3–10 mm in diameter which were found to arise from the L6‐L7 and L7‐S1 articular process joints. These cysts had signal intensities that varied from hyperintense to the cerebrospinal fluid (CSF) on T1 weighted images to isointense to CSF on T2 weighted images. Decompressive surgery in conjunction with arthrodesis of these joints resulted in resolution of clinical signs. The dog remained pain‐free 1½ years following surgical therapy.
MAGNETIC RESONANCE IMAGING FEATURES OF MULTILOBULAR OSTEOCHONDROSARCOMA IN 3 DOGS
Authors: Lipsitz David , Levitski Robin E. , Berry Wayne L.
Published: May 2005

Three dogs with multilobular osteochondrosarcoma of the skull were evaluated using magnetic resonance (MR) imaging. Spin echo T1, T2, proton weighted and post contrast T1W images were obtained with a 1.5 Tesla magnet. The MR imaging findings were similar in all three dogs with mixed signal intensities in the T1W, T2W and proton weighted images and fairly large areas of contrast enhancement in the post contrast T1W images. The extent of brain and soft tissue involvement were well delineated and provided useful information concerning surgical planning. MR imaging provided a useful method of evaluating dogs with skull tumors.
MAGNETIC RESONANCE IMAGING FEATURES OF CERVICAL STENOTIC MYELOPATHY IN 21 DOGS
Authors: Lipsitz David , Levitski Robin E. , Chauvet Anne E. , Berry Wayne L.
Published: May 2005

The cervical spine of 21 dogs with clinical signs of cervical stenotic myelopathy was evaluated using magnetic resonance (MR) imaging. Spin echo T1, T2 and gradient echo T2 weighted images were obtained with a 1.5 Tesla magnet in 12 dogs and a 1.0 Tesla magnet in 9 dogs. Sagittal or parasagittal T1W and T2W images were helpful in determining the presence of spinal cord compression or degenerative disease of the articular processes. Transverse T1W and T2W images were the most useful for the identification of dorsolateral spinal cord compression secondary to soft tissue and ligament hypertrophy, as well as synovial cysts, associated with the articular processes. The MR imaging findings were consistent with the surgical findings in all 14 dogs that underwent surgery. Magnetic resonance imaging provided a safe, non‐invasive method of evaluating the cervical spine in dogs suspected of having cervical stenotic myelopathy.
THORACIC RADIOGRAPHIC APPEARANCE IN THE NORMAL LLAMA
Authors: Mattoon John S. , Gerros Terry C. , Brimacombe Michael
Published: May 2005

The goal of this study was to collect quantitative and qualitative radiographic information of the normal adult llama thorax. Standing right‐left lateral radiographs of the thorax of 16 normal llamas were made. Normal ratios of cardiac height, width, and height plus width to thoracic vertebrae 3–5 and thoracic height were calculated. Normal values determined for tracheal angle of divergence from the thoracic spine, cardiophrenic and cardiosternal contact are additional potential indicators of cardiac enlargement. Ratios of normal pulmonary artery and vein, caudal vena cava and trachea to the height of the fourth thoracic vertebra should allow identification of pathology of these structures. Observations regarding pulmonary vessels and airways, thoracic spine, sternebrae and portions of the gastrointestinal tract observed on thoracic radiographs are also included. It is proposed that these normal values and observations can be used to better evaluate diseases of the cardiovascular and respiratory systems of adult Ilamas.
MULTICENTRIC LYMPHOSARCOMA IN A DOG WITH MULTIPLE‐SITE SKELETAL INVOLVEMENT
Authors: Dhaliwal Ravinder S. , Reed Ann L. , Kitchell Barbara E.
Published: May 2005

In this report the authors describe an unusual clinical presentation of lymphosarcoma (LSA) in a dog. A 9‐year‐old, neutered male, Golden Retriever was presented with a primary complaint of sudden onset of tetraparesis. Routine survey radiographs revealed multiple‐site bony lesions and the histology revealed a diagnosis of LSA with diffuse skeletal and soft tissue involvement. The dog responded poorly to medical management and was euthanized on day two due to poor prognosis. Malignant LSA of the bone is a rare extranodal clinicopathologic entity and presents both a diagnostic and therapeutic hurdle. Reports of this kind are sparse and currently no optimal treatment for this entity has been determined.
A RETROSPECTIVE STUDY INTO THE EFFECTS OF OPERATOR EXPERIENCE ON THE ACCURACY OF ULTRASOUND IN THE DIAGNOSIS OF GASTRIC NEOPLASIA IN DOGS
Authors: Easton Suzanne
Published: May 2005

The accuracy of three diagnostic techniques in two separate time periods was examined. In the first time period, 18 dogs were referred to the University of Bristol with signs suggestive of gastric neoplasia. Of these 18 dogs, 7 had a positive diagnosis of gastric neoplasia from histopathology samples (38% prevalence). The sensitivity of ultrasound was found to be 42.9% with a specificity of 63.6%. A year later the study was repeated with 40 cases referred for investigation. Of these 40 dogs, 16 had a positive histopathologic diagnosis of gastric neoplasia (40% prevalence). At this time the sensitivity of ultrasound had increased to 81.3% and the specificity had increased to 70.8%. The increase in sensitivity was attributed to an increase in operator experience in the performance of the ultrasound examination. This improvement in sensitivity and experience resulted in a greater accuracy at detecting the presence of gastric neoplasia.
MITRAL ANNULUS MOTION AS DETERMINED BY M‐MODE ECHOCARDIOGRAPHY IN NORMAL DOGS AND DOGS WITH CARDIAC DISEASE
Authors: Schober Karsten E. , Fuentes Virginia Luis
Published: May 2005

M‐mode echocardiography was used to assess apical mitral annulus motion (MAM) in 103 normal dogs and 101 dogs with cardiac disease, to obtain information on systolic left ventricular long axis function. In normal dogs, a close relationship was found between MAM and body weight (r = 0.80, P < 0.001). There was a weak correlation between MAM and heart rate (r =−0.25, P < 0.05), but no correlation between MAM and age or left ventricular shortening fraction (P > 0.05). Mean MAM (95% confidence intervals) were established for normal dogs of differing body weight, and were 0.70 cm (0.65 to 0.75) in dogs < 15 kg, 1.08 cm (1.03 to 1.13) in dogs weighing 15 to 40 kg, and 1.51 cm (1.21 to 1.81) in dogs > 40 kg. “Cut‐off” values to define decreased MAM for normal dogs of differing body weight were 0.45 cm (dogs < 15 kg), 0.80 cm (dogs 15–40 kg), and 1.20 cm (dogs > 40 kg). In dogs with cardiac disease, median MAM was normal in mitral valve endocardiosis or aortic stenosis, but significantly decreased (P < 0.05) in dilated cardiomyopathy. All dogs with mitral valve endocardiosis (n = 54) or aortic stenosis (n = 26) had MAM above the above‐mentioned “cut‐off” values, suggesting normal or increased left ventricular longitudinal systolic shortening, whereas 81 % (17/21) of dogs with dilated cardiomyopathy had MAM below the “cut‐off value”, indicating decreased long axis systolic function. It is concluded that MAM may be used to evaluate systolic left ventricular long axis performance in dogs and may add useful information on global left ventricular contraction dynamics.