COMPARISON BETWEEN THORACIC RADIOGRAPHIC FINDINGS AND POSTMORTEM DIAGNOSIS OF THORACIC DISEASES IN DYSPNEIC COMPANION RATS (RATTUS NORVEGICUS).

Companion rats are often presented to veterinarians for respiratory difficulties. Dyspnea in rats is most commonly due to infectious pneumonia, and thoracic neoplasia can go undiagnosed ante mortem due to a mistaken interpretation of pneumonia. In domestic carnivores, pulmonary nodular patterns have been shown to correlate with lung neoplastic diseases and infectious diseases. The main objective of this retrospective case series study was to determine whether certain radiographic criteria could be correlated with the presence of thoracic infectious disease and neoplastic disease in companion rats. A secondary objective was to determine whether the patient's sex and age were different between rats diagnosed with infectious versus neoplastic disease. Medical records and thoracic radiographs of dyspneic companion rats presented to the University of California at Davis, William R. Pritchard Veterinary Medical Teaching Hospital during the time period from January 2000 to December 2014 were reviewed. Rats with postmortem confirmation of thoracic lesions were included in the study. Thoracic radiographs were evaluated for positioning, lesion distribution, lung lobe involved, pulmonary pattern, mediastinal and pleural lesions by three observers blinded to diagnosis. Thirty rats were included in the study, including 23 rats with an infectious disease and seven with neoplasia. Mediastinal lesions were significantly more prevalent in the group diagnosed with thoracic neoplasia (P = 0.031), in particular cranially (P = 0.048). Although there was an overlap between the two groups, findings indicated that the presence of cranial mediastinal lesions may be helpful for differentiating neoplastic from infectious disease in rats.

Isolation of Trueperella pyogenes in a case of thoracic and abdominal abscess in a galago (Otolemur garnettii).

BACKGROUND: An adult male galago (Otolemur garnettii) presented for fight wounds following pairing for breeding. Treatment was symptomatic with recovery. Following resolution, the animal re-presented and died, despite additional treatment. METHODS: Necropsy, histopathology, bacterial cultures, and 16S RNA sequencing. RESULTS: A large intrathoracic/intra-abdominal abscess due to Trueperella pyogenes was found at necropsy. CONCLUSIONS: T. pyogenes should be considered in abscesses/wounds of galagos.

Surgical views: thoracoscopy: basic principles, anesthetic concerns, instrumentation, and thoracic access.

Thoracoscopic surgery offers an exciting method for treating a variety of thoracic disease processes. To date, several thoracoscopic procedures have been described in veterinary patients. This article discusses the basic principles of thoracoscopic surgery and thoracic access, anesthetic concerns, and required instrumentation. A companion article discussing the surgical techniques of thoracoscopic pericardial window creation, subphrenic pericardectomy, thoracoscopic lung biopsy, lung lobectomy, thoracic duct ligation, and cranial mediastinal mass excision will be published in the February 2013 issue.

Intrathoracic pseudocyst in a kitten.

A 2-month-old, intact, female domestic shorthair kitten presented with a history of acute-onset dyspnoea. Severe dyspnoea and tachypnoea were noted on physical examination. Serosanguinous fluid, consistent with a modified transudate, was aspirated from the pleural cavity immediately after the physical examination, with an immediate decrease in respiratory rate and effort. The thorax was radiographed and the entire left hemithorax appeared to be filled with a large soft tissue density mass. Thoracic ultrasound was performed and a cystic structure, measuring 3.0 cm × 1.5 cm, was seen in the left hemithorax. An explorative thoracotomy was performed and a mass obliterating the left hemithorax was found. The mass was removed by a combination of blunt and sharp dissection. A final diagnosis of thoracic pseudocyst was made on histological examination of the tissue. The mass was described as a sterile process characteristic of an organised seroma or haematoma. Recovery from surgery was uneventful and the kitten was discharged 48 h postoperatively. The kitten was still alive with no recurrence of clinical signs at the time of writing this report, 8 months postoperatively.

Thoracic computed tomography in feline patients without use of chemical restraint.

Computed tomography (CT) and thoracic radiography were performed in nonsedated, nonanesthetized, cats with thoracic disease. The final diagnosis was obtained with echocardiography, cytology, histopathology, necropsy, or response to therapy. For CT imaging, cats were in a positioning device using a 16 multislice helical CT system. Fifty-four cats had CT imaging of which 50 had thoracic radiography. The most common diagnoses were lung neoplasia, lower airway disease, and cardiomyopathy (nine each). Other disease groups included mediastinal mass (eight), infection (seven), trauma (four), and hernia (three). CT provided additional correct diagnoses in 28% (14/50) and additional information in 74% (37/50) of the cats. Additional correct diagnoses achieved only with CT were most common for cats with lower airway disease. The most common additional findings with CT were lung nodules (n=4), lung masses (n=4), bronchiectasis (n=4), and mediastinal lymphadenopathy (n=3). Survey CT led to a significant different diagnosis or different prognosis in 20 of the 50 cats that were imaged both modalities. Contrast CT was performed in 19 cats, most commonly in cats with lung neoplasia (n=6), a mediastinal mass (n=4) or an infection (n=3), and provided additional correct diagnosis in two cats not achieved with survey CT. Thoracic CT using a positioning device in diseased awake cats is feasible, safe, and clinically useful.

Computed tomography characteristics of canine tracheobronchial lymph node metastasis.

Tracheobronchial lymph node evaluation is critical for accurate staging of canine thoracic neoplasia and is more accurately achieved with computed tomography (CT) than radiography. Thoracic CT scans of 18 canine patients with known tracheobronchial lymph node histopathology and 10 clinically normal dogs were compared to establish if enlargement or contrast enhancement pattern correlated with metastatic status. Absolute lymph node size and three anatomically normalized lymph node ratios were significantly correlated with metastasis or severe granulomatous lymphadenitis (P < 0.0003). Transverse maximum lymph node diameter of 12 mm or lymph node to thoracic body ratio of 1.05 are proposed cutoffs, above which metastatic involvement is very likely; however, only minimal accuracy was gained with normalized ratios. Lymph node contrast enhancement pattern was also significantly correlated to disease. A heterogenous and/or ring pattern was related to metastatic disease (P = 0.03). Recommended protocol for CT examination of the tracheobronchial lymph nodes is 1-1.5 mm slices and intervals, intravenous contrast, and control of respiratory motion.

Surgical procedures of the thorax.

Thoracic disease is common in cattle and is a significant cause for economic losses in the stocker and feedlot industries. In most cases, economic constraints limit diagnostic investigation and affect treatment options. Although medical management is, by far, the most appropriate therapeutic intervention in such cases, surgical management of some respiratory diseases can allow for profitable return to productivity. Surgical procedures of the thorax most often involve thoracotomy or pericardiotomy. Tracheal reconstruction and invasion of the mediastinum are rarely indicated in cattle.

Indications, outcomes and complications following lateral thoracotomy in dogs and cats.

OBJECTIVES: Lateral thoracotomy is widely used for surgical management of thoracic diseases in small animals. The purpose of this paper is to describe the indications for lateral thoracotomy in dogs and cats and the associated outcomes and complications. METHODS: Medical records of animals undergoing lateral thoracotomy were reviewed and owners contacted regarding complications and survival. Relationships between signalment and treatment variables and outcome variables were investigated. RESULTS: Seventy dogs and 13 cats underwent lateral thoracotomy. Sixty-two per cent of cats and 91 per cent of dogs survived to discharge. Survival to discharge was significantly lower in cats than dogs, for neoplastic than non-neoplastic disease and in older animals. Survival to discharge was higher in animals undergoing patent ductus arteriosus ligation than in those undergoing lung lobectomy or oesophageal surgery. Survival to discharge was not related to surgeon experience. The incidence of complications was not related to species, age, disease, duration of surgery, surgeon experience or duration of thoracostomy tube placement. A low complication rate (5 per cent) was associated with thoracostomy tubes. CLINICAL SIGNIFICANCE: The approach of lateral thoracotomy has a minimal complication rate and animals with a disease requiring this approach have a high survival rate.

Ultrasonographic characteristics of abdominal and thoracic abscesses in cattle and buffaloes.

Six cows and five buffaloes with abdominal and thoracic abscesses were examined clinically and ultrasonographically. There was a wide range of clinical signs and at least 50% of the animals exhibited dull demeanour, anorexia, abdominal pain, recurrent tympany and/or weight loss. Three cases of abdominal abscesses were imaged in the left ventral abdomen between the rumen and abdominal wall, two cases were imaged at the xiphoid cartilage near the reticular wall and one case was imaged on the right ventral abdomen between the jejunum and right abdominal wall. Four cases of thoracic abscesses were imaged in the third intercostal space on the left side; however, one case of abscess was imaged in the fourth intercostal space, also on the left side. The content of the abscess was echogenic in eight animals and anechoic in three. In three animals, the content of the abscess was partitioned by echogenic septae. In two cows, the echogenic content of the abscess was surrounded by a narrow rim of anechoic fluid. The diameters of the abscesses were 5-10 cm in three cows, 11-15 cm in seven cows and >15 cm in one cow. In every case, the diagnosis was confirmed by centesis and aspiration of the abscess, which yielded purulent material. There were biochemical data of hypoalbuminaemia and hyperglobulinaemia and 90% of tested animals had neutrophilia. Five cows were examined at slaughter, where the ultrasonographic diagnosis was confirmed.

Computed tomography-guided fine-needle aspirate and tissue-core biopsy of intrathoracic lesions in thirty dogs and cats.

Medical records and computed tomography (CT) images were reviewed retrospectively for 30 animals (27 dogs, two cats, one cougar) in which CT-guided intrathoracic fine-needle aspirates (FNA) (12), core biopsies (10) or both (8) were performed. Sample interpretation was listed as diagnostic or nondiagnostic and nonneoplasia or neoplasia. Diagnostic results were inconclusive in 35% FNA and 17% biopsies. FNA and biopsy interpretations were in agreement in seven patients, one nonneoplasia, and six neoplasia. A clinical diagnosis was made in 65% FNA and 83% biopsies. When 18 patients with confirmed diagnoses were used, overall accuracy for diagnosis was 92% for FNA and biopsy and the sensitivity for neoplasia was 91% using fine needle aspirate and 80% using biopsy. Complications seen on CT images were noted in 43% of patients, four pneumothorax, five pulmonary hemorrhage, and four with both. No clinical manifestations were noted and treatment was not necessary. Significant correlation was noted between complications and penetration of aerated lung, but not with lesion location, type of disease, method of sampling, width of mass and depth of aerated lung penetrated. CT-guided sampling is relatively safe and useful in the diagnosis of intra-thoracic lesions, especially neoplasia. FNA samples are nondiagnostic more often than biopsy samples. Sub-clinical pneumothorax and hemorrhage are common when aerated lung is penetrated.

Use of radiography in combination with computed tomography for the assessment of noncardiac thoracic disease in the dog and cat.

Computed tomography (CT) of the thorax was performed in 28 dogs and five cats and findings were compared with previous thoracic radiographs. The sample population included all animals that had thoracic radiographs and a CT study within 5 days of each other, where the complete imaging studies were available for review. Thoracic radiographs were considered indeterminate in 31 patients and CT examinations were done to acquire additional information. The presence of additional information from CT relating to presence of pathology, location of pathology, extent of pathology, and involvement of mediastinal structures was recorded. Whether there was a change in diagnosis based on the CT findings was also recorded. In only 4/33 animals (all dogs) did CT fail to provide any new information for the parameters evaluated when compared with survey thoracic radiographs. Additional information about the pathology that was present was gained by CT in 5/5 cats and 21/ 28 dogs. New information on compartmental location of pathology was seen in 4/5 cats and 19/28 dogs. New information on pathology extent was noted in 5/5 cats and 20/28 dogs. Additional information regarding involvement of mediastinal structures was obtained in 2/5 cats and 10/28 dogs. A change in diagnosis was made in 3/5 cats and 13/28 dogs. In conclusion, CT is a valuable tool for evaluating intrathoracic disease. CT provides additional cross-sectional anatomic information that can aid in anatomic localization and evaluation of the extent of the pathology in question.

[Thorax examination by computed tomography: general aspects and presentation of clinical cases]. / Examen thoracique par tomodensitométrie: Généralités et présentation de cas cliniques.

This article describes the application of the helicoidal tomography for the study of mediastinal and pulmonal affections by small animals. The global presentation is completed by clinical cases that show the interest in this technic. A thymoma, a chronic pleuresia due to thorns and a mediastinal cranio-dorsal neoplasia provoking only lameness signs will be presentated in details.

Diagnostic ultrasonography in cattle with thoracic disease.

The pleura and lungs were evaluated by means of sonography in 55 bovine patients with diseases of the thoracic cavity. For these ultrasound examinations, a range of transducers was used. As the lung surface was most often involved in cases of pulmonary disease, it was possible to detect ultrasonographically bronchopneumonia, consolidation, pleural effusion, pulmonary emphysema and pleuritis. Determination of the amount of lung tissue affected provided prognostic information. It was not possible to visualise lesions located deeper within the lungs where peripheral tissue was not affected. A diagnosis of thoracic disease was made on the basis of clinical and ultrasonographic findings and confirmed in 33 cases at necropsy.

The diagnosis and treatment of a thoracic abscess in an alpaca.

A 6-month-old alpaca presented for lethargy, failure to thrive and leucocytosis. Diagnostic procedures, including thoracic ultrasound, radiographs and a computed tomography scan, were used to document a thoracic mass. Based on appearance and ultrasound-guided aspiration of purulent material, the mass was determined to be a large abscess. The abscess was treated with surgical drainage and long-term antibiotic therapy. The origin of this thoracic abscess was felt to be the caudal mediastinum, secondary to bacterial seeding of the caudal mediastinal lymph nodes. Although an aetiological agent was not definitively determined, the most likely was Actinomyces spp or Arcanobacterium pyogenes. The alpaca made a complete recovery following treatment.

Video-assisted thoracoscopy.

Thoracoscopy is a minimally invasive operative endoscopic procedure designed for visual inspection of the thoracic cavity. The use of small, highly maneuverable, rigid telescopes allows visualization beyond what is possible by standard operative techniques. The use of a small video camera attached to a standard rigid telescope allows the operator and assistants to view a simultaneous, enlarged, and clear image. This article focuses on the basic diagnostic and surgical techniques used in veterinary video-assisted thoracoscopy.

Non-cardiac thoracic ultrasound in 75 feline and canine patients.

The purpose of this study was to describe the ultrasonographic appearance of non-cardiac diseases of the small animal thorax. Ultrasound images from a total of 75 animals (26 cats and 49 dogs) were compared to cytologic, histopathologic, and necropsy findings. Clinical diagnoses included neoplasia of the mediastinum, pleura, or lungs (43); idiopathic mediastinal cyst (3); diaphragmatic or peritoneopericardial hernia (4); lung lobe torsion (1); pulmonary eosinophilic infiltrates (1); and idiopathic, chylous, congestive heart failure, or lymphangiectasia associated pleural effusion (14). In the remaining 9 patients, a definitive diagnosis was not obtained. Ultrasound-guided fine needle aspirate was performed in 56 patients; 1 of these also had an ultrasound-guided tissue core biopsy. Of the fine needle aspirates, 51 (91%) were diagnostic. Ultrasound examination, particularly when accompanied by guided tissue sampling, can be a valuable tool in the diagnosis of non-cardiac intrathoracic lesions.

Thoracoscopy in horses.

With the recent development of video-assisted thoracic surgery, visual inspection of the thoracic cavity has been used to provide a more accurate diagnosis and prognosis of thoracic diseases and to better manage these diseases. Equipment, techniques, and complications for standing thoracoscopy in horses are described.

Thoracic and abdominal blastomycosis in a horse.

A 5-year-old Quarter Horse mare was examined because of lethargy, fever, and weight loss of 1 month's duration. Thoracic auscultation revealed decreased lung sounds cranioventrally. Thoracic ultrasonography revealed bilateral anechoic areas with hyperechoic strands, consistent with pleural effusion and fibrin tags. A large amount of free fluid was evident during abdominal ultrasonography. Abnormalities included anemia, hyperproteinemia, hyperglobulinemia, hyperfibrinogenemia, and hypoalbuminemia. Thoracic radiography revealed alveolar infiltrates in the cranial and caudoventral lung fields. A cavitary mass, consistent with an abscess, could be seen caudodorsal to the crura of the diaphragm. Ultrasonographic evaluation of this area revealed a hypoechoic mass with septations. Bilateral thoracocentesis was performed. Bacterial culture of the pleural fluid did not yield growth, but Blastomyces dermatitidis was isolated from pleural fluid, abdominal fluid, and an aspirate of the abscess. The mare was euthanatized, and a diagnosis of thoracic and abdominal blastomycosis was confirmed at necropsy.