CT features of feline cystic bronchiectasis forming mass lesions.

Case series summary: Cystic bronchiectasis was diagnosed in three cats with known histories of chronic coughing using CT and histopathology. CT of the lungs revealed large space-occupying lesions that compressed and displaced unaffected pulmonary parenchyma and vessels. The masses were soft tissue attenuating in two cases and gas-cavitated with areas of dependent fluid in one case. All three cats were found to have mineral attenuating material in lesions and in other dilatated airways. Generalized bronchial wall thickening was also present and indicative of chronic lower airway disease. These findings were supported by histopathology showing inflammatory changes and dilatated airways in the collected tissues. In the two cases in which post-contrast CT series were acquired, the lesions had rim-enhancement. Relevance and novel information: Cystic bronchiectasis is a rare presentation of bronchiectasis in cats and may mimic a pulmonary mass lesion, which could be mistaken for neoplasia or abscessation. The lack of central enhancement or presence of gas cavitation on CT, concurrent presence of diffuse bronchial wall thickening, other areas of bronchiectasis and the presence of broncholithiasis may alert the clinician to the possibility of cystic bronchiectasis related to chronic lower airway disease.

Diagnostic imaging and histopathologic features of rounded atelectasis in four cats and one dog: A descriptive case series study.

In humans, rounded atelectasis is defined as focal lung collapse that radiologically appears as a round mass-like lesion in the periphery of the lung. In general, human patients with rounded atelectasis have a history of pleural effusion and abnormal pleura and characteristic CT findings help to distinguish rounded atelectasis from pulmonary neoplasia without the need for invasive surgical biopsy. This retrospective multi-center case series describes rounded atelectasis in four cats and one dog. Chylothorax was seen in four patients and an eosinophilic and lymphoplasmacytic effusion was seen in one patient. All patients had solitary or multifocal subpleural pulmonary masses (26 masses total in 5 patients) with diffuse, multifocal, or focal visceral and parietal pleural thickening. All the masses but one were broad-based towards the visceral pleura. Masses were most common in the ventral or lateral aspect of the lungs. Indistinctness at the hilar aspect of the lesion was seen in all masses; a "comet tail" sign was seen in 14 of 26 masses. On postcontrast images, the lesions were homogeneously enhanced in 24 of 26 masses and heterogeneous in two of 26 masses. Other findings include ground glass opacities (n = 5), parenchymal bands (n = 4), mild to moderate lymphadenopathy (n = 4), and compensatory hyperinflation of the lung lobes not affected by atelectasis (n = 2). Histopathology of four cases revealed atelectasis with fixed pleural folds, chronic pleuritis, and mild to moderate pleural fibrosis. Awareness of rounded atelectasis in veterinary species will enable inclusion of a benign etiology into the differential diagnosis for subpleural masses in cases with pleural abnormalities.

Severity of nasopharyngeal collapse before and after corrective upper airway surgery in brachycephalic dogs.

OBJECTIVE: To determine the severity of nasopharyngeal collapse in brachycephalic dogs before and after corrective airway surgery. ANIMALS: Twenty-three brachycephalic dogs (21 with clinical signs referrable to the upper airway) and nine clinically normal nonbrachycephalic dogs (controls). METHODS: Dogs were evaluated with fluoroscopy awake and standing with the head in a neutral position. The magnitude of nasopharyngeal collapse was measured as the maximum reduction in the dorsoventral dimension of the nasopharynx during respiration and expressed as a percentage. Brachycephalic dogs were anesthetized, the airway evaluated, and corrective upper airway surgery (alaplasty, staphylectomy, sacculectomy, tonsillectomy) was performed. A cohort (n = 11) of the surgically treated brachycephalic dogs had fluoroscopy repeated a minimum of 6 weeks after surgery. RESULTS: Median preoperative reduction in the dorsoventral dimensions of the nasopharynx was greater in brachycephalic dogs (65%; range: 8-100%) than in controls (10%; range: 1-24%, p = .0001). Surgery did not improve the reduction in dorsoventral diameter of the nasopharynx during respiration in brachycephalic dogs (n = 11) postoperatively (p = .0505). CONCLUSION AND CLINICAL SIGNIFICANCE: Nasopharyngeal collapse was a common and sometimes severe component of brachycephalic airway obstruction syndrome in the cohort of dogs evaluated. The lack of significant postoperative improvement may represent a type II error, a failure to adequately address anatomical abnormalities that increase resistance to airflow, or inadequate upper airway dilator muscle function in some brachycephalic dogs.

What Is Your Diagnosis?

In collaboration with the American College of Veterinary Radiology.

High-field MRI using standard pulse sequences has moderate to substantial interobserver agreement and good accuracy for differentiation between intracranial extra-axial histiocytic sarcoma and meningioma in dogs.

Intracranial extra-axial histiocytic sarcoma shares common MRI features with meningioma. As histiocytic sarcoma carries a generally worse prognosis than meningioma, the ability to differentiate between these two neoplasms is of clinical value. The aim of this retrospective diagnostic accuracy and observer agreement study was to evaluate the accuracy and reliability of high-field MRI to differentiate between these two tumors, using standard pulse sequences and published MRI features. A total of 51 dogs were included (26 meningiomas and 25 histiocytic sarcomas). Magnetic resonance imaging examinations were independently assessed by three experienced board-certified radiologists, evaluating 18 imaging features. They were asked to assign each case to one of three categories (meningioma, histiocytic sarcoma, and undetermined). Agreement for the MRI diagnosis across all three reviewers was moderate (κ 0.54) while paired interobserver agreement ranged from moderate to substantial (κ 0.58-0.74) with percent agreement ranging between 86.1% and 87.7%. Overall, the probability of correctly diagnosing meningioma in a dog with this tumor ranged between 79.2% and 94.4%, and the probability of correctly diagnosing histiocytic sarcoma in a dog with this tumor ranged between 76.0% and 92.3%. The overall probability to diagnose the correct tumor, irrespective of type, ranged between 79.2% and 89.7%. Histiocytic sarcomas tended to have more extensive edema and more often had combined perilesional and distant meningeal enhancement affecting both pachy- and leptomeninges, while for meningiomas, meningeal enhancement tended to more commonly be perilesional and pachymeningeal. Imaging features that seemed more useful to make a correct diagnosis included "location/type of meningeal enhancement," "osseous changes in the adjacent neurocranium," "cystic changes," and "herniation severity."

Serial abdominal radiographs do not significantly increase accuracy of diagnosis of gastrointestinal mechanical obstruction due to occult foreign bodies in dogs and cats.

Abdominal radiographs are commonly used in dogs and cats that present with gastrointestinal signs. When initial abdominal radiographs are equivocal for the presence or absence of gastrointestinal mechanical obstruction, follow-up abdominal radiographs may be recommended. Based on our review of the literature, no published study has been performed to evaluate the clinical utility of serial abdominal radiographs in such cases. The purpose of this study is to determine whether follow-up abdominal radiographs increase diagnostic accuracy for mechanical obstruction. A prospective cohort study was performed on client-owned dogs and cats with clinical concern for gastrointestinal mechanical obstruction and initial abdominal radiographs inconclusive for the presence of obstruction. Follow-up abdominal radiographs were performed between 7 and 28 h of the initial radiographs; an abdominal ultrasound performed within 3 h of the follow-up study served as the gold standard. A total of 57 patients (40 dogs and 17 cats) were recruited; 19 of 57 cases (11 dogs; 8 cats) were mechanically obstructed, all with nonradiopaque foreign bodies. Four blinded reviewers (2 radiologists, 1 radiology resident, 1 criticalist) separately assessed the initial and the combined initial/follow-up radiographic studies for diagnosis of mechanical obstruction; for each observer, there was no significant change in accuracy (P = .058-.87) for the diagnosis of mechanical obstruction. Given the lack of significant increase in diagnostic accuracy using follow-up radiographs in cases of occult gastrointestinal mechanical obstruction, other diagnostic options (eg, abdominal ultrasonography) could be considered when survey abdominal radiographs are inconclusive for the diagnosis of mechanical obstruction in dogs and cats.

Radiation exposure of dogs and cats undergoing fluoroscopic procedures and for operators performing those procedures.

OBJECTIVE: To evaluate radiation exposure of dogs and cats undergoing procedures requiring intraoperative fluoroscopy and for operators performing those procedures. SAMPLE: 360 fluoroscopic procedures performed at 2 academic institutions between 2012 and 2015. PROCEDURES: Fluoroscopic procedures were classified as vascular, urinary, respiratory, cardiac, gastrointestinal, and orthopedic. Fluoroscopy operators were classified as interventional radiology-trained clinicians, orthopedic surgeons, soft tissue surgeons, internists, and cardiologists. Total radiation exposure in milligrays and total fluoroscopy time in minutes were obtained from dose reports for 4 C-arm units. Kruskal-Wallis equality of populations rank tests and Dunn pairwise comparisons were used to compare differences in time and exposure among procedures and operators. RESULTS: Fluoroscopy time (median, 35.80 minutes; range, 0.60 to 84.70 minutes) was significantly greater and radiation exposure (median, 137.00 mGy; range, 3.00 to 617.51 mGy) was significantly higher for vascular procedures than for other procedures. Median total radiation exposure was significantly higher for procedures performed by interventional radiology-trained clinicians (16.10 mGy; range, 0.44 to 617.50 mGy), cardiologists (25.82 mGy; range, 0.33 to 287.45 mGy), and internists (25.24 mGy; range, 3.58 to 185.79 mGy). CONCLUSIONS AND CLINICAL RELEVANCE: Vascular fluoroscopic procedures were associated with significantly longer fluoroscopy time and higher radiation exposure than were other evaluated fluoroscopic procedures. Future studies should focus on quantitative radiation monitoring for patients and operators, importance of operator training, intraoperative safety measures, and protocols for postoperative monitoring of patients.

Complications and clinical utility of ultrasonographically guided pyelocentesis and antegrade pyelography in cats and dogs: 49 cases (2007-2015).

OBJECTIVE: To describe the diagnostic utility and clinical safety of ultrasonographically guided percutaneous pyelocentesis and antegrade pyelography in cats and dogs. DESIGN: Retrospective case series. ANIMALS: 39 cats and 10 dogs with 55 affected kidneys. PROCEDURES: Medical records were reviewed to identify cats and dogs that underwent ultrasonographically guided pyelocentesis and antegrade pyelography between June 1, 2007, and December 31, 2015. Data collected included procedure descriptions; results of diagnostic imaging, urine cytologic evaluation, and bacterial culture; and evidence of complications. Animals were assigned to the pyelocentesis group (underwent only pyelocentesis) or to the antegrade pyelography group (underwent pyelocentesis followed immediately by pyelography). RESULTS: The diagnostic rate for pyelography was 94% (31/33; 95% confidence interval [CI], 80.4% to 98.9%). The total, minor, and major complication rates for both treatment groups combined were 25% (95% CI, 15.8% to 38.3%), 24% (95% CI, 14.4% to 36.3%), and 2% (95% CI, 0.09% to 9.6%), respectively. Performing bacterial culture of urine obtained by pyelocentesis did not provide an advantage over performing bacterial culture of urine obtained from the lower urinary tract. CONCLUSIONS AND CLINICAL RELEVANCE: Findings indicated that ultrasonographically guided pyelocentesis and antegrade pyelography were well-tolerated techniques for investigating upper urinary tract disease in cats and dogs and that pyelography had a higher diagnostic rate than previously reported; therefore, pyelography should be considered for identification of mechanical and functional ureteral patency abnormalities in cats and dogs.

Ability of ultrasonography to predict the presence and location of histologic lesions in the small intestine of cats.

BACKGROUND: Diagnosis of infiltrative small intestinal (SI) disease in cats is challenging, and debate continues regarding optimal biopsy techniques. Ultrasonography may facilitate selection of biopsy type and location. HYPOTHESIS/OBJECTIVES: Assess ability of ultrasonography to predict histologic lesions by SI segment and tissue layer. ANIMALS: One-hundred sixty-nine cats that had abdominal ultrasonography and full-thickness SI biopsies performed. METHODS: Ultrasonographic images and full-thickness biopsy samples were retrospectively reviewed, and each SI wall layer evaluated for lesions according to published standards. RESULTS: Ultrasonographic SI lesions were present in 132 cats (63 duodenum; 115 jejunum; 71 ileum). Samples were obtained at laparotomy (60) or necropsy (109). Ultrasonographic abnormalities had high positive predictive value (PPV) for histologic lesions (duodenum, 82.0%; 95% confidence interval [CI], 68.6-91.4; jejunum, 91.0%; 95% CI, 81.5-96.6; ileum, 88.1%; 95% CI, 74.4-96.0), but poor negative predictive value (duodenum, 27.1%; 95% CI, 17.2-39.1; jejunum, 27.3%; 95% CI, 10.7-50.2; ileum, 40.4%; 95% CI, 26.4-55.7). The ability of ultrasonography to predict histologic lesions in this population, which had high disease prevalence (SI histologic lesions in 78.1% of cats) was high for mucosal lesions (PPV, 72.7%-100%) but low for submucosal or muscularis lesions (PPV, 18.9%-57.1%). CONCLUSIONS AND CLINICAL IMPORTANCE: In a population with high disease prevalence, most cats with SI mucosal ultrasonographic lesions will have mucosal histologic lesions. Small intestinal submucosal and muscularis ultrasonographic lesions are not predictive of histologic disease in those layers, suggesting that full-thickness biopsy may not be essential in these cats. Ultrasonography may help guide decisions about biopsy type in individual cats.

Diagnostic utility of ultrasonography for detection of the cause and location of ureteral obstruction in cats: 71 cases (2010-2016).

OBJECTIVE To assess the utility of ultrasonography to detect the cause and location of ureteral obstruction in cats and to identify factors associated with agreement between ultrasonographic and surgical findings. STUDY DESIGN Retrospective case series. ANIMALS 71 cats. PROCEDURES Medical records were searched to identify cats that had ureteral obstruction diagnosed ultrasonographically and that subsequently underwent exploratory laparotomy. Patient signalment, ultrasonographic findings, interventions performed, and surgical findings were recorded. Cause and location of ureteral obstruction as assessed by ultrasonography were compared with surgical findings. Sensitivity, specificity, and positive predictive value of ultrasonography for detection of ureteroliths and strictures were calculated. Statistical analysis was performed to identify factors associated with agreement between ultrasonographic and surgical findings. RESULTS There was significant, moderate agreement between ultrasonographic and surgical findings for the cause and location of ureteral obstruction. Signalment variables, ureter affected (left vs right), and presence of retroperitoneal effusion were not associated with this agreement. Sensitivity was 98% and 44%, specificity was 96% and 98%, and positive predictive value was 98% and 88% for detection of ureteroliths and strictures, respectively, by ultrasonography. CONCLUSIONS AND CLINICAL RELEVANCE Ultrasonography was highly sensitive for detection of ureteroliths that caused ureteral obstruction but was considerably less sensitive for detection of ureteral strictures in the study population. Future prospective studies are needed to determine the role of advanced imaging in assessing cats with ureteral abnormalities. (J Am Vet Med Assoc 2019;254:710-715).

Nodules and masses are associated with malignant pleural effusion in dogs and cats but many other intrathoracic CT features are poor predictors of the effusion type.

Thoracic CT may be used in the workup of patients with pleural effusion. In humans, certain pleural features on CT aid in diagnosing an underlying cause for pleural effusion, whereas this is not well studied in veterinary medicine. This retrospective cross-sectional analytical study assessed pleural and other intrathoracic abnormalities on CT in dogs and cats with pleural effusion and explored potential discriminatory features between effusion types. Eighty-nine dogs and 32 cats with pleural cytology and/or histopathology were categorized into malignant pleural disease (15 dogs and 11 cats), pyothorax (34 dogs and 7 cats), chylothorax (20 dogs and 11 cats), transudative (11 dogs and 2 cats), and hemorrhagic effusion (9 dogs and 1 cat). Multivariable logistic regression analysis comparing malignancy to other effusions found that older patient age (dogs: odds ratio 1.28, P = 0.015; cats: odds ratio 1.53, P = 0.005), nodular diaphragmatic pleural thickening (dogs: odds ratio 7.64, P = 0.021; cats: odds ratio 13.67, P = 0.031), costal pleural masses (dogs: odds ratio 21.50, P = 0.018; cats: odds ratio 32.74, P = 0.019), and pulmonary masses (dogs: odds ratio 44.67, P = 0.002; cats: odds ratio 18.26, P = 0.077) were associated with malignancy. In dogs, any costal pleural abnormality (odds ratio 47.55, P = 0.002) and pulmonary masses (odds ratio 10.05, P = 0.004) were associated with malignancy/pyothorax, whereas any costal pleural abnormality (odds ratio 0.14, P = 0.006) and sternal lymphadenopathy (odds ratio 0.22, P = 0.040) were inversely associated with transudates. There were, however, many overlapping abnormalities between effusion types, so further diagnostic testing remains important for diagnosis.

Radiographic distribution of ureteral stones in 78 cats.

OBJECTIVE: To document the distribution of ureteral stones in cats. STUDY DESIGN: Retrospective case series. ANIMALS: Seventy-eight cats. METHODS: Abdominal radiographs with ureteral stones were reviewed. The location of stones was categorized as proximal ureter (PU), midureter (MU), or ureterovesicular junction (UVJ). The number, size, and location of stones were recorded by using the kidneys and vertebral bodies as landmarks. Stone location in cats with 1 versus multiple stones was assessed. Descriptive statistics were used to describe the incidence of ureteral stone location. RESULTS: Among cats with a single stone (44%, 34/78), 44% (15/34) had a stone in the PU, 41% (14/34) had a stone in the MU, and 15% (5/34) had a stone at the UVJ. When multiple stones were present, 61% (27/44) of cats had at least 1 stone located in the PU, 70% (31/44) had at least 1 stone located in the MU, and 34% (15/44) had at least 1 stone located at the UVJ. The L4 vertebral body most commonly marked stone location in cats with 1 stone and the most distal stone in cats with multiple stones. Stones located at the UVJ site were more common in male (37%) than in female (12%) cats (P = 0.004). Larger stone size was associated with a more proximal location (P = 0.04). CONCLUSION: Ureteral stones were more commonly located in the PU and the MU than in the UVJ. UVJ stones were more common in male than in female cats, and larger stones had a more proximal location. CLINICAL SIGNIFICANCE: This study enhances our understanding of feline ureteral stone location and identifies a correlation between stone location and stone size.

Diagnostic Accuracy of Ultrasound to Predict the Location of Solitary Hepatic Masses in Dogs.

OBJECTIVE: To determine the sensitivity, specificity, and predictive value of ultrasonography for localizing hepatic masses in dogs and to identify patient factors associated with diagnostic accuracy. STUDY DESIGN: Retrospective cross-sectional study. ANIMALS: Client-owned dogs (n = 137). METHODS: Medical records of dogs diagnosed with a solitary hepatic mass on abdominal ultrasound and confirmed by laparotomy or laparoscopy were reviewed. Location of the mass predicted by ultrasound was compared to mass location identified at surgery. Ultrasound exams were performed by or under the supervision of a board certified radiologist. Sensitivity, specificity, and positive predictive values were calculated. Patient factors associated with accurate localization were identified using logistic regression. RESULTS: Ultrasound correctly localized liver masses in 71/137 dogs (51.8%). The sensitivity of ultrasound localization was 55% for left and right division masses and 29% for central division masses. The specificity was 98% for left division masses, 87% for central division masses, and 89% for right division masses. Correct localization was 3.2 times more likely when the mass arose from the right or left division compared to the central division (odds ratio [OR] 3.2; 95% confidence intervals [CI] 1.1, 9.0; P = .030). Correct localization was significantly less likely when diffuse or multifocal hepatic disease was present (OR 0.32; 95% CI 0.15, 0.70; P = .004). CONCLUSION: Ultrasound was specific but not sensitive for localizing hepatic masses, and localization accuracy was influenced by mass location and the presence of concurrent liver pathology. These findings should be taken into consideration by veterinary surgeons using ultrasound examination to guide patient treatment and surgical planning.

Computed tomographic findings in 57 cats with primary pulmonary neoplasia.

Primary pulmonary neoplasia is relatively uncommon in cats and generally has a poor prognosis. In this multicenter, retrospective study of 57 cats with pulmonary neoplasia, the most frequent presenting signs were anorexia/inappetence (39%) and cough (37%). The pulmonary tumors were considered to be incidental findings in 9% cats. In computed tomographic (CT) images, primary pulmonary tumors appeared as a pulmonary mass in 55 (96%) cats and as a disseminated pulmonary lesion without a defined mass in two (4%) cats. Most pulmonary tumors were in the caudal lobes, with 28 (49%) in the right caudal lobe and 17 (30%) in the left caudal lobe. CT features associated with pulmonary tumors included mass in contact with visceral pleura (96%), irregular margins (83%), well-defined borders (79%), bronchial compression (74%), gas-containing cavities (63%), foci of mineral attenuation (56%), and bronchial invasion (19%). The mean (range) maximal dimension of the pulmonary masses was 3.5 cm (1.1-11.5 cm). Additional foci of pulmonary disease compatible with metastasis were observed in 53% cats. Pleural fluid was evident in 30% cats and pulmonary thrombosis in 12% cats. The histologic diagnoses were 47 (82%) adenocarcinomas, six (11%) tumors of bronchial origin, three (5%) adenosquamous cell carcinomas, and one (2%) squamous cell carcinoma. In this series, adenocarcinoma was the predominant tumor type, but shared many features with less common tumor types. No associations were identified between tumor type and CT features. Prevalence of suspected intrapulmonary metastasis was higher than in previous radiographic studies of cats with lung tumors.

Suspected hypertrophic osteopathy in an ancient canid: Differential diagnosis of possible etiologies.

Hypertrophic osteopathy (HO) has been reported in numerous mammalian species, but no reports address the range of conditions that can lead to HO, or the implications of those conditions, for archaeological diagnosis. We describe suspected HO from skeletal remains of an ancient large domestic dog recovered in Iowa, USA, at the Cherokee Sewer site. Canid remains from this site date 7430-7020calBP. The site is believed to have been a temporary, low-intensity campsite where bison were procured. Over 100 specimens from two small dogs, two large dogs, and a coyote, are present in the archaeofaunal assemblage. We document five pathological metapodials; an affected left ulna, radius, tuber calcaneus, accessory carpal, radial carpal; and an affected right central, second, and third tarsal within in a proliferative mass. HO was suspected based on gross morphology, radiography, and computed tomography. HO is a paraneoplastic syndrome with undetermined underlying pathogenesis; neuroendocrine complication of a number of neoplastic and non-neoplastic diseases is suspected. We review known disease associations of HO to provide a balanced field for considering differential diagnosis of suspect archaeological specimens, and suggest that definitive diagnosis of HO, or suspected HO, may be impossible in many instances where only skeletal remains are available for study.

Computed tomographic features of pneumothorax secondary to a bronchopleural fistula in two dogs.

A bronchopleural fistula (BPF) can lead to continuous pneumothorax and is rarely reported clinically in dogs. This report describes computed tomographic (CT) findings in two dogs with BPFs and subsequent continuous pneumothoraces that necessitated thoracotomy. Both dogs had a peripheral BPF in the right caudal lung lobe. The fistula in one dog was secondary to a previous foreign body migration, and the fistula in the other was thought to be secondary to dirofilariasis. On both CT examinations, a dilated subsegmental bronchus was seen communicating with the pleural space at the center of a focal, concave region of parenchymal consolidation. Multiplanar reformatting aided in identification and characterization of the BPF. The pneumothoraces resolved after right caudal lobectomy in both dogs. CT has the potential to identify BPFs, such as secondary to foreign body migration or dirofilariasis.

Computed tomographic characteristics of odontogenic neoplasms in dogs.

Odontogenic neoplasms are locally invasive oral tumors in dogs. The purpose of this retrospective study was to describe CT characteristics for varying histopathologic types of canine odontogenic neoplasms. A board-certified veterinary radiologist who was unaware of histologic findings reviewed and scored imaging studies. A total of 29 dogs were included in the study. Twenty-three of these dogs had concurrent dental radiographs. The most common CT characteristics for all tumor types were a direct association with or in the region of multiple teeth in 96.4% (27/28), contrast enhancement in 96.3% (26/27), alveolar bone lysis in 93.1% (27/29), and mass-associated tooth displacement in 85.2% (23/27). Mass-associated cyst-like structures were identified in 53.6% (15/28) and were only present in tumors containing odontogenic epithelium. Canine acanthomatous ameloblastomas (n = 15) appeared as extra-osseous (10/15) or intra-osseous (5/15) masses. Intra-osseous canine acanthomatous ameloblastomas were more likely to have mass-associated cyst-like structures and were subjectively more aggressive when compared with extra-osseous canine acanthomatous ameloblastomas. Amyloid-producing odontogenic tumors (n = 3) had subjectively uniform CT imaging characteristics and consisted of round soft tissue and mineral attenuating masses with multiple associated cyst-like structures. Fibromatous epulides of periodontal ligament origin (n = 4) were contrast enhancing extra-osseous masses that were rarely referred for CT examinations and 25% (1/4) were not visible with CT. Other odontogenic tumors were less represented or had more variable CT imaging characteristics. Mass-associated tooth destruction was appreciated more often with dental radiographs and extra-oral tumor extension was identified more often with CT.

Sensitivity, positive predictive value, and interobserver variability of computed tomography in the diagnosis of bullae associated with spontaneous pneumothorax in dogs: 19 cases (2003-2012).

OBJECTIVE: To determine the sensitivity, positive predictive value, and interobserver variability of CT in the detection of bullae associated with spontaneous pneumothorax in dogs. DESIGN: Retrospective case series. ANIMALS: 19 dogs with spontaneous pneumothorax caused by rupture of bullae. PROCEDURES: Dogs that had CT for spontaneous pneumothorax caused by rupture of bullae confirmed at surgery (median sternotomy) or necropsy were included. Patient signalment, CT protocols, and bulla location, size, and number were obtained from the medical records. Computed tomographic images were reviewed by 3 board-certified radiologists who reported on the location, size, and number of bullae as well as the subjective severity of pneumothorax. RESULTS: Sensitivities of the 3 readers for bulla detection were 42.3%, 57.7%, and 57.7%, with positive predictive values of 52.4%, 14.2%, and 8.4%, respectively, with the latter 2 readers having a high rate of false-positive diagnoses. There was good interobserver agreement (κ = 0.640) for correct identification of bullae. Increasing size of the bulla was significantly associated with a correct CT diagnosis in 1 reader but not in the other 2 readers. Correct diagnosis was not associated with slice thickness, ventilation protocol, or degree of pneumothorax. CONCLUSIONS AND CLINICAL RELEVANCE: Sensitivity and positive predictive value of CT for bulla detection were low. Results suggested that CT is potentially an ineffective preoperative diagnostic technique in dogs with spontaneous pneumothorax caused by bulla rupture because lesions can be missed or incorrectly diagnosed. Bulla size may affect visibility on CT.

Safety of contrast-enhanced ultrasonography in dogs and cats: 488 cases (2002-2011).

OBJECTIVE: To determine the incidence of adverse events within 24 hours after contrast-enhanced ultrasonography (CEUS) in dogs and cats and compare the risk of death within 24 hours after imaging for animals that underwent ultrasonography with and without injection of a contrast agent. DESIGN: Retrospective case-control study. ANIMALS: 750 animals (411 case dogs, 238 control dogs, 77 case cats, and 24 control cats). PROCEDURES: At 11 institutions, medical records were reviewed of dogs and cats that had CEUS performed (cases) as were medical records of dogs and cats with clinical signs similar to those of case animals that had ultrasonography performed without injection of a contrast agent (controls). Information regarding signalment; preexisting disease; type, dose, and administration route of contrast agent used; immediate (within 1 hour after CEUS) and delayed (> 1 and ≤ 24 hours after CEUS) adverse events; and occurrence and cause of death (when available) was extracted from each medical record. Risk of death within 24 hours after ultrasonography was compared between case and control animals. RESULTS: Of the 411 case dogs, 3 had immediate adverse events (vomiting or syncope) and 1 had a delayed adverse event (vomiting). No adverse events were recorded for case cats. Twenty-three of 357 (6.4%) clinically ill case animals and 14 of 262 (5.3%) clinically ill control animals died within 24 hours after ultrasonography; risk of death did not differ between cases and controls. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that CEUS was safe in dogs and cats.