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Copyright of Canadian Veterinary Journal / Revue Vétérinaire Canadienne is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This article provides information on the radiographic imaging of thoracic lymph nodes in dogs. It highlights the importance of understanding the locations and drainage patterns of these lymph nodes for accurate interpretation of thoracic radiographs and differential diagnoses. The article specifically focuses on the sternal, mediastinal, and tracheobronchial lymph nodes, discussing their normal appearance, potential causes of enlargement, and diagnostic considerations. It also mentions that lymphadenomegaly in adult dogs is often associated with neoplastic or inflammatory conditions, while antigenic stimulation and immune system development are additional considerations for young animals. The text emphasizes the significance of understanding the lymphatic system in dogs and specifically focuses on the tracheobronchial lymph nodes, which are commonly affected by neoplasia and infections. This knowledge can assist veterinarians in diagnosing and selecting appropriate testing for dogs with thoracic lymphadenomegaly. [Extracted from the article]

A 16‐month‐old Sarplaninac Shepherd cross dog presented for a 1‐month history of a productive cough that was unresponsive to an empirical 10‐day course of cephalexin. Thoracic computed tomography (CT) showed multifocal, well‐defined, smoothly marginated, soft tissue attenuating, minimally contrast enhancing nodular airway mural thickenings protruding into the airway lumen in the caudal trachea and principal bronchi. These nodules were also visualized on bronchoscopy, and cytology revealed parasitic larvae consistent with Oslerus osleri. The dog was treated with oral fenbendazole for 26 days. Clinical signs resolved within 3 weeks of treatment initiation and had not relapsed at 7‐month follow‐up. [ABSTRACT FROM AUTHOR]

Canine optic pathway structures are often contoured on CT images, despite the difficulty of visualizing the optic pathway with CT using standard planes. The purpose of this prospective, analytical, diagnostic accuracy study was to examine the accuracy of optic pathway contouring by veterinary radiation oncologists (ROs) before and after training on optic plane contouring. Optic pathway contours used as the gold standard for comparison were created based on expert consensus from registered CT and MRI for eight dogs. Twenty‐one ROs contoured the optic pathway on CT using their preferred method, and again following atlas and video training demonstrating contouring on the optic plane. The Dice similarity coefficient (DSC) was used to assess contour accuracy. A multilevel mixed model with random effects to account for repeated measures was used to examine DSC differences. The median DSC (5th and 95th percentile) before and after training was 0.31 (0.06, 0.48) and 0.41 (0.18, 0.53), respectively. The mean DSC was significantly higher after training compared with before training (mean difference = 0.10; 95% CI, 0.08–0.12; P < 0.001) across all observers and patients. DSC values were comparable to those reported (0.4–0.5) for segmentation of the optic chiasm and nerves in human patients. Contour accuracy improved after training but remained low, potentially due to the small optic pathway volumes. When registered CT‐MRI images are not available, our study supports routine addition of an optic plane with specific window settings to improve segmentation accuracy in mesaticephalic dogs ≥11 kg. [ABSTRACT FROM AUTHOR]

Learning by comparison is a frequently employed education strategy used across many disciplines and levels. Interpreting radiographs requires both skills of perception and pattern recognition, which makes comparison techniques particularly useful in this field. In this randomized, prospective, parallel‐group study, students enrolled in second and third‐year radiology veterinary courses were given a case‐based thoracic radiographic interpretation assignment. A cohort of the participants was given cases with side‐by‐side comparison normal images while the other cohort only had access to the cases. Twelve cases in total were presented to the students, with 10 cases depicting examples of common thoracic pathologies, while 2 cases were examples of normal. Radiographs of both feline and canine species were represented. Correctness of response to multiple choice questions was tracked, as was year and group (group 1: non compare, Control; group 2: compare, Intervention). Students assigned to group 1 had a lower percentage of correct answers than students assigned to group 2 (45% Control vs. 52% Intervention; P = 0.01). This indicates that side‐by‐side comparison to a normal example is helpful in identifying disease. No statistical significance was noted for the correctness of responses according to the year of training (P = 0.90). The overall poor performance on the assignment, regardless of group or year, shows that students in the early years of undergraduate veterinary radiology training struggle with the interpretation of common pathologies, likely a result of a lack of exposure to a multitude of cases and normal variants. [ABSTRACT FROM AUTHOR]

A 9‐week‐old, male domestic shorthair presented with a 2‐week history of progressive hindlimb weakness and reduction in normal play behaviour. At 17 weeks of age, the patient exhibited progressive hindlimb paresis and ataxia and had developed facial dysmorphia and bilateral corneal clouding, prompting investigation into a mucopolysaccharidosis disorder. Peripheral blood cytology, increased urinary glycosaminoglycan excretion and radiographic findings (generalised epiphyseal dysplasia, coxofemoral luxation and vertebral fusion) suggested mucopolysaccharidosis. Definitive diagnosis was obtained through serum enzymatic testing, which yielded a complete deficiency in β‐glucuronidase and increased compensatory activity in α‐L‐iduronidase and B‐arylsulfatase. This pattern was consistent with a diagnosis of feline mucopolysaccharidosis VII, and palliative therapy was initially implemented. The patient ultimately died at 21 months of age. [ABSTRACT FROM AUTHOR]

A 7‐year‐old spayed female ferret was presented to the Veterinary Teaching Hospital at the Western College of Veterinary Medicine for a slow‐growing mass involving the base of the tail. Radiographs revealed a large, irregularly marginated mineralized mass centered on the fifth to seventh caudal vertebrae with osteolysis of the affected caudal vertebrae. A partial caudectomy was performed, and histopathology was consistent with a chordoma. This is the first case report describing the radiographic appearance of a chordoma in the proximal tail and only the second report to describe radiographic findings in a ferret. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Journal of Veterinary Research / Revue Canadienne de Recherche Vétérinaire is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Veterinary workers use lead shielding for protection against harm from ionizing radiation during diagnostic imaging. Surface lead on shielding has been reported as a potential exposure hazard. The purpose of this prospective, analytical, descriptive study was to measure surface lead on lead‐containing shielding in the field service and small animal radiology areas of a veterinary teaching hospital, and to examine potential risk factors for surface lead. Surface lead on a convenience sample of 54 lead shielding items was measured in a commercial laboratory using inductively coupled plasma mass spectrometry. The median and range of surface lead for aprons, thyroid collars, and gloves were 3.6 μg/dm2 (range, 1.3‐22.4 μg/dm2), 23.1 μg/dm2 (range, 2.6‐116 μg/dm2), and 134 μg/dm2 (range, 1.5‐155 μg/dm2), respectively. In the final multivariable analysis, the mean surface lead on thyroid collars and gloves was higher than on aprons (relative differences 4.8, 95% confidence interval [CI] 2.2, 10.5, P < 0.001; and 9.5, 95% CI 4.4, 20.6, P < 0.001, respectively). The mean surface lead on shielding in the worst condition was higher than on shielding in the intermediate and best conditions (P < 0.001). Lead shielding provides effective protection against the harmful effects of ionizing radiation, and shielding should always be worn during radiation exposure. Based on our findings and the common use of lead shielding in veterinary workplaces, we recommend that employers inform workers of this hazard and provide training on steps to mitigate exposure, including the use of disposable gloves when wearing lead shielding and handwashing after use. [ABSTRACT FROM AUTHOR]

Background: Historical and recent literature disagree on whether a higher PO 131I dosage, compared to IV or SC routes, is required for successful resolution of spontaneous hyperthyroidism in cats, necessitating investigation into the effect of PO and injectable radioactive iodine administration on % thyroidal radioactive iodine uptake (RAIU). Hypothesis/Objectives: To investigate the effect of PO and SC routes of 123I administration on paired % thyroidal RAIU in euthyroid cats. Specifically, a 1.5‐fold difference (50% relative change) was hypothesized, which in absolute terms can be expressed as a 3.25% increase in the mean %RAIU of 7.04% after PO 123I administration to 10.56% after SC dosing. Animals Seven healthy euthyroid teaching‐research colony cats. Methods: A randomized, radiologist‐blinded crossover study comparing %RAIU after PO and SC 123I administration. Results: Percentage thyroidal RAIU values (mean ± SD; 95% confidence interval) after PO (4.81% ± 1.63%; 3.30%‐6.23%) and SC (5.26% ± 2.43%; 3.01%‐7.51%) 123I administration were associated with a median within‐pair absolute difference of 0.2% (range: min, 0.1%‐max, 4.9%). Statistical significance was not achieved (P =.45). Six of 7 cats had a within‐pair absolute difference of 0.1% to 0.9% (relative change of 4%‐20%), but a single outlier cat had a within‐pair absolute difference of 4.9% (relative change of 108%). Conclusions and Clinical Importance: This study did not detect an effect of 123I administration route on paired % thyroidal RAIU in euthyroid cats. However, a type 2 statistical error due to small sample size is possible. [ABSTRACT FROM AUTHOR]

Copyright of Canadian Veterinary Journal / Revue Vétérinaire Canadienne is the property of Canadian Veterinary Medical Association and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Abstract: Staging and therapeutic planning for dogs with malignant disease in the popliteal lymph node are based on the expected patterns of lymphatic drainage from the lymph node. The medial iliac lymph nodes are known to receive efferent lymph from the popliteal lymph node; however, an accessory popliteal efferent pathway with direct connection to the sacral lymph nodes has also been less frequently reported. The primary objective of this prospective, anatomic study was to describe the frequency of various patterns of lymphatic drainage of the popliteal lymph node. With informed client consent, 50 adult dogs with no known disease of the lymphatic system underwent computed tomographic lymphography after ultrasound‐guided, percutaneous injection of 350 mg/ml iohexol into a popliteal lymph node. In all 50 dogs, the popliteal lymph node drained directly to the ipsilateral medial iliac lymph node through multiple lymphatic vessels that coursed along the medial thigh. In 26% (13/50) of dogs, efferent vessels also drained from the popliteal lymph node directly to the internal iliac and/or sacral lymph nodes, coursing laterally through the gluteal region and passing over the dorsal aspect of the pelvis. Lymphatic connections between the right and left medial iliac and right and left internal iliac lymph nodes were found. Based on our findings, the internal iliac and sacral lymph nodes should be considered when staging or planning therapy for dogs with malignant disease in the popliteal lymph node. [ABSTRACT FROM AUTHOR]

OBJECTIVE To describe animal owners’ experiences with palliative radiation therapy (PRT) of pets and identify factors influencing satisfaction with their pets’ treatment. DESIGN Retrospective, cross-sectional study. SAMPLE 118 owners of dogs, cats, or rabbits. PROCEDURES Medical records were searched to identify animals that underwent PRT between 2004 and 2013. Signalment, tumor-related data, and outcome information were recorded. Owners completed an electronic survey assessing satisfaction with treatment (ie, satisfaction with the decision for their pet to undergo PRT and indication that they would choose PRT for their pet again), expectations regarding PRT, and perceptions of their pets’ quality of life (QOL) and signs of discomfort from acute adverse radiation effects. Additional data regarding practical aspects of treatment, pet death, communications with veterinarians, and owner demographics were collected. Variables were tested for association with measures of owner satisfaction. RESULTS 92 of 116 (79%) owners were satisfied with the decision to have their pets undergo PRT. Most (92/118 [78%]) owners reported their pet’s QOL improved after PRT; these owners were significantly more likely to be satisfied than those who did not report improved QOL. Owners who perceived their pets had discomfort from adverse radiation effects (38/116 [33%]) were significantly less likely to be satisfied than owners who did not report this observation. Measures of satisfaction were not associated with patient survival time. Twenty-one of 118 (18%) owners indicated they expected PRT would cure their pet’s tumor. CONCLUSIONS AND CLINICAL RELEVANCE Results suggested that short life expectancy should not deter recommendation of PRT for pets. Protocols that minimize risk of acute adverse effects may be advantageous. Veterinarians should attempt to ensure that owners understand the goals of PRT. [ABSTRACT FROM AUTHOR]