Lung lobe torsion in association with a chronic diaphragmatic hernia and haemorrhagic pleural effusion in a cat

CLINICAL SUMMARY: This report describes torsion of the right cranial lung lobe in a cat with haemorrhagic pleural effusion and a chronic diaphragmatic hernia. Surgical treatment comprising lung lobectomy without de-rotation, and repair of the diaphragmatic defect, led to an uneventful recovery. PRACTICAL RELEVANCE: Lung lobe torsion is a rare condition in cats. While spontaneous lung lobe torsions may occur, a frequent association with underlying thoracic disease has been recognised in cats. However, neither haemorrhagic pleural effusion nor diaphragmatic hernia have been previously described in cats with lung lobe torsions, although they have been documented in dogs and humans. In a cat with suspected lung lobe torsion, a thorough search for an underlying disease should be undertaken.     

Evaluation of lung lobe torsion in Pugs: 7 cases (1991-2004)

OBJECTIVE: To determine whether there is a predis-position for lung lobe torsion (LLT) in Pugs and describe clinical findings associated with LLT in that breed, compared with findings in other breeds. DESIGN: Retrospective case series. ANIMALS: 7 Pugs and 16 dogs of other breeds. PROCEDURE: Information collected from records included signalment, history, lung lobe affected, results of clinicopathologic testing, histologic findings, diagnostic imaging results, surgical treatment, and outcome. RESULTS: 23 dogs were diagnosed with LLT, 10 of which were large-breed dogs and 13 of which were small-breed dogs. Seven of the small-breed dogs were Pugs. Pugs with LLT were significantly overrepresented, compared with the general hospital population. Affected Pugs ranged in age from 4.5 months to 4 years (median, 1.5 years). Six of the 7 Pugs had no predisposing conditions, and 6 were male. Six Pugs survived to discharge. Of the other small- and large-breed dogs, 3 of 6 and 5 of 10 survived to discharge, respectively. None of the Pugs were readmitted for complications or recurrence. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that young male Pugs may be predisposed to developing spontaneous LLT. The prognosis for survival and resolution of clinical signs in Pugs with LLT appeared to be excellent. Factors contributing to the development of LLT in Pugs are not known.     

Right cranial lung lobe torsion after a diaphragmatic rupture repair in a Jack Russell terrier

A seven-year-old male Jack Russell terrier was presented with a history of coughing, generalised weakness and lethargy 10 days after an abdominal coeliotomy to repair a large diaphragmatic rupture. Thoracic radiographs demonstrated a soft tissue mass in the midcaudal right thoracic cavity. Ultrasonographic studies, bronchoscopy and subsequent exploratory thoracotomy confirmed a diagnosis of a right cranial lung lobe torsion (LLT), with an anomalous caudodorsal displacement of the affected lobe. LLT should be considered as a differential diagnosis for respiratory tract disease following diaphragmatic rupture repair.     

RADIOGRAPHIC DIAGNOSIS OF LUNG LOBE TORSION

Clinical data, thoracic radiographs, ultrasonographic exams, and histopathologic reports in 13 dogs and two cats with confirmed lung lobe torsion were reviewed. Age of dogs ranged from 4 months to 11.5 years, (mean of 6.4 years) and several breeds of large and small dogs were represented. Right middle lobe torsion was predominant in large dogs (five of eight large breed dogs) and left cranial lobe torsion was more commonly seen in small dogs (three of five small-breed dogs). Two domestic short-hair cats, 10 and 14 years of age, had right cranial and right middle lobe torsion, respectively. Underlying thoracic disease was found in only five of 15 patients. On thoracic radiographs, increased lobar opacity and pleural effusion were found in all patients (100%). Small dispersed air bubbles were found within the affected lobe of 13 patients (87%). This pattern, which was the result of vesicular emphysema, was variably extensive, and became more evident on follow-up radiographs in five of six dogs. The lobar bronchi could be seen in only eight of 15 patients (54%), and appeared irregular, focally narrowed or blunted in six of the eight patients, and displaced in five of the eight. Other common radiographic findings included mediastinal shift (nine), curved and dorsally displaced trachea (seven), and axial rotation of the carina (seven). Ultrasonography was used in seven patients and considered generally useful, although variable signs were observed.     

Liver lobe torsion in dogs: 13 cases (1995-2004)

OBJECTIVE: To determine history, results of diagnostic testing, surgical findings, complications, and outcome for dogs with liver lobe torsion (LLT). DESIGN: Retrospective case series. ANIMALS: 12 dogs (1 with 2 episodes). PROCEDURE: Signalment, clinical signs, clinicopathologic findings, radiographic and ultrasonographic findings, surgical and histologic findings, complications, and hospitalization time were evaluated. RESULTS: The most common clinical signs were nonspecific abnormalities (eg, vomiting, lethargy, and anorexia) of acute or chronic duration. All dogs were large-breed dogs (median body weight, 37.2 kg [82 lb]). Biochemical abnormalities included high alanine amino-transferase (n = 12) and aspartate aminotransferase (11) activities. Results of abdominal ultrasonography were supportive of the diagnosis in 5 of 8 cases. Affected lobes included the left medial lobe (n = 4), left lateral lobe (3), papillary process of the caudate lobe (2), caudate lobe (1), and right lateral lobe (1). Exploratory celiotomy and liver lobectomy were performed in 12 of 13 cases, and in 11 of those 12 cases, the dog survived. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that development of nonspecific clinical signs of vomiting, lethargy, and anorexia in conjunction with high serum hepatic enzyme activities and mature neutrophilia in a medium-sized or large-breed dog should increase the index of suspicion for LLT. Abdominal ultrasonography with Doppler assessment may be useful in establishing the diagnosis. The long-term outcome for dogs that survive the hospitalization period is excellent.     

Lung lobe torsion in dogs: 22 cases (1981-1999)

OBJECTIVE: To identify breed disposition, postoperative complications, and outcome in dogs with lung lobe torsion. DESIGN: Retrospective study. ANIMALS: 22 client-owned dogs. PROCEDURE: Information on signalment; history; clinical findings; results of clinicopathologic testing, diagnostic imaging, and pleural fluid analysis; surgical treatment; intra- and postoperative complications; histologic findings; and outcome were obtained from medical records. RESULTS: All 22 dogs had pleural effusion; dyspnea was the most common reason for examination. Fifteen dogs were large deep-chested breeds; 5 were toy breeds. Afghan Hounds were overrepresented, compared with the hospital population. One dog was euthanatized without treatment; the remaining dogs underwent exploratory thoracotomy and lung lobectomy. Eleven dogs recovered from surgery without complications, but 3 of these later died of thoracic disease. Four dogs survived to discharge but had clinically important complications within 2 months, including chylothorax, mediastinal mesothelioma, gastric dilatation, and a second lung lobe torsion. Six dogs died or were euthanatized within 2 weeks after surgery because of acute respiratory distress syndrome, pneumonia, septic shock, pneumothorax, or chylothorax. Chylothorax was diagnosed in 8 of the 22 dogs, including 4 Afghan Hounds. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that lung lobe torsion is rare in dogs and develops most frequently in large deep-chested dogs, particularly Afghan Hounds. Other predisposing causes were not identified, but an association with chylothorax was evident, especially in Afghan Hounds. Prognosis for dogs with lung lobe torsion was fair to guarded.     

Hepatic lobe torsion in 3 dogs and a cat

OBJECTIVE: To describe the clinical features of hepatic lobe torsions in 3 dogs and 1 cat. STUDY DESIGN: Retrospective clinical study. ANIMALS: Three client-owned dogs and 1 client-owned cat. METHODS: Medical records were reviewed, and information regarding signalment, clinical signs, physical-exam findings, diagnostic tests performed, treatment, outcome, and follow-up was retrieved. RESULTS: Clinical signs existed for 4 hours to 1 week before examination. Signs were nonspecific in 2 animals that did not have an obvious cause for the hepatic torsion. These signs consisted of lethargy (2), polyuria/polydypsia (2), and anorexia (1). In the other 2 animals, signs were suggestive of the underlying cause of the hepatic lobe torsion. In 1 dog, the torsion was associated with a traumatic diaphragmatic hernia. The cat had a concurrent hemoabdomen secondary to a ruptured hepatocellular carcinoma. Bloodwork abnormalities were nonspecific. Twisted liver lobes included the left lateral lobe (2), the caudate lobe (1), and the right medial lobe (1). Surgical resection (2) or repositioning (1) of the affected liver lobe was attempted in the 3 dogs, and was successful in 2. CONCLUSION: Hepatic lobe torsion is a rare problem but has been reported in humans, rabbits, dogs, pigs, a cat, and a horse. The left lateral liver lobe is most frequently affected. This condition may be idiopathic or associated with neoplasia or absence of ligamentous support (congenital or traumatic) to the liver. CLINICAL RELEVANCE: Prompt surgical resection or repositioning of the involved liver lobe can lead to a successful outcome, avoiding the deleterious effects of venous obstruction such as thrombosis and subsequent necrosis.     

Non-coagulopathic spontaneous hemothorax in dogs

Objective: To determine the history, clinicopathologic findings, underlying causes, and outcomes for dogs with non‐coagulopathic spontaneous hemothorax. Design: Retrospective case series. Setting: University referral hospital. Animals: Sixteen client‐owned dogs. Interventions: The medical records database was searched for dogs with hemothorax. Dogs with trauma, secondary coagulopathy, recent thoracic surgery, or pericardial intervention were excluded. For the remaining dogs, signalment, clinical signs, clinicopathologic findings, radiographic findings, histopathologic findings, interventions, and outcome were recorded. Measurements and main results: The most common presenting signs were tachypnea (n=9) and lethargy (n=5), typically of <1‐week duration. The most common cause of non‐coagulopathic spontaneous hemothorax in dogs was neoplasia, which was diagnosed in 14 patients (88%). Identified malignancies included hemangiosarcoma (n=1), malignant mesothelioma (n=1), metastatic ovarian carcinoma (n=1), osteosarcoma (n=2), and pulmonary carcinoma (n=2). An intrathoracic mass was visualized in 7 other dogs; however, histopathology was not obtained. Pancreatitis and lung lobe torsion were each diagnosed in 1 dog, and survival was prolonged with both surviving at least 1 year post discharge. Only 6 of 14 dogs that were diagnosed with neoplasia were discharged from the hospital. For the 4 dogs with cancer with available outcome data, median survival time was 16 days (range 1–70 days). Two dogs were lost to follow‐up and had unknown survival times. Conclusions: The development of non‐coagulopathic spontaneous hemothorax warrants a high‐index suspicion for neoplasia, in particular thoracic wall neoplasia.     

Radiography, computed tomography and virtual bronchoscopy in four dogs and two cats with lung lobe torsion

This report describes the imaging features of radiography, computed tomography and virtual bronchoscopy in dogs and cats with lung lobe torsions. The medical records, thoracic radiographs and computed tomography images of four dogs and two cats with confirmed lung lobe torsions were retrospectively reviewed. Computed tomography with virtual bronchoscopy showed bronchial narrowing, collapse or occlusion in all six animals, while this was only appreciated on one radiographic examination. A tapering terminating angle of the air-filled bronchus proximal or distal to the collapsed region was seen only on computed tomography and virtual bronchoscopy in all six animals. The vesicular emphysema pattern typical of lung lobe torsion was seen on three computed tomographies but only on one radiographic examination. The lung lobe torsion-specific findings of vesicular emphysema and a proximally narrowed or occluded bronchus were more easily recognised on computed tomography and virtual bronchoscopy than with radiographs. Computed tomography slices acquired through the bronchus and lung lobe of interest in a cat or dog with possible lung lobe torsion can be reformatted into virtual bronchoscopic images that can be utilised along with computed tomography to help make a more definitive preoperative diagnosis.     

CT is helpful for the detection and presurgical planning of lung perforation in dogs with spontaneous pneumothorax induced by grass awn migration: 22 cases

Spontaneous pneumothorax induced by grass awns accounts for 5% of spontaneous pneumothorax and 22.5% of thoracic grass awn cases. Previous studies report limited interest of CT for spontaneous pneumothorax. Aims of this retrospective case series were to describe CT features of this condition and determine if CT features can efficiently localize the perforation site. Dogs that had a spontaneous pneumothorax, CT examination, thoracic surgery, and confirmed lung perforation due to a grass awn were included. Computed tomography studies were reviewed and compared to the surgical findings.  In 19 of 22 (86.4%) dogs, the pneumothorax or its recurrence were ipsilateral to the perforation site. The perforation site was identified in 21 of 22 (95.5%) dogs and involved the caudal lobes in 20 of 22 (90.9%) cases. The lateralization and the involved lung lobe corresponded to surgical findings in 21 of 22(95.5%) dogs. The perforation site was characterized as a soft tissue attenuating focus lying against an extensive pleural thickening in 21 of 22(95.5%) dogs. An adjacent defect in the visceral pleura was seen in 13 of 22(59.1%) dogs. A grass awn was seen in 11 of 22(50%) dogs.  The pneumothorax distribution and grass awn position consistently indicated the perforation side in this sample of dogs. The comparison with surgical findings suggests CT might be helpful for future presurgical planning of this etiology for pneumothorax.     

COMPUTED TOMOGRAPHIC FEATURES OF LUNG LOBE TORSION

The imaging features of lung lobe torsion in 10 dogs (nine complete, one partial torsion) acquired with a helical single‐slice computed tomography (CT) unit are described. Attenuation values of normal, rotated, and adjacent collapsed lung lobes before and after intravenous contrast medium administration were compared. Affected lung lobes were: left cranial (5), right middle (3), right cranial (1), and left caudal (1). CT findings in nine dogs with complete lung lobe torsion included pleural effusion and an abruptly ending bronchus. In eight of these dogs, enlargement, consolidation, emphysema of the affected lung lobe, and mediastinal shift to the contralateral side were present. Rotated lung lobes did not enhance, whereas adjacent collapsed and aerated lung lobes did (P<0.05). Apnea induced with hyperventilation or breath‐hold is essential to reduce motion artefacts and obtain a diagnostic study.     

Spontaneous lung lobe torsion in two pugs

Two, young adult, male pugs presented for spontaneous left-cranial lung lobe torsions. Clinical signs associated with these two cases included increased weakness, increased respiratory effort, tachypnea, acute collapse, lethargy, anorexia, and cyanosis. The torsed lung lobes were excised using a thoracoabdominal stapling device without detorsing the lobes. Both dogs recovered uneventfully, and at least one year postoperatively, no clinical abnormalities were noted by their owners. Results of this report suggest that spontaneous lung lobe torsion in pugs occurs and should be a differential diagnosis for pugs with increased respiratory effort, tachypnea, nonproductive cough, acute collapse, cyanosis, and lethargy. Surgical excision may be curative.     

Lung lobe torsion associated with chest wall defects in a dog

An 8-year-old, spayed, female poodle presented with exercise intolerance, lethargy, respiratory distress, retching, hyporexia and diarrhoea. Thoracic radiographs revealed increased opacity in the left cranial thoracic region. The fifth and sixth ribs appeared to be bulging cranially to caudally, and CT and surgical exploration confirmed the presence of a thoracic wall defect in that area. CT showed abrupt occlusion of the bronchus that branches into the left cranial lobe and consolidation of the caudal segment of left cranial lung lobe, which led to the diagnosis of lung lobe torsion. A thoracotomy was performed, the twisted lung lobe was surgically excised, and the defect in the thoracic wall was repaired. Respiratory distress gradually improved after the surgery, and there were no identified complications within the 2-year period following the procedure. Based on our literature search, this is the first reported case of lung lobe torsion caused by a thoracic wall defect in a dog.     

RETROSPECTIVE ASSESSMENT OF THORACIC RADIOGRAPHIC FINDINGS IN METASTATIC CANINE HEMANGIOSARCOMA

Twenty-one dogs with histopathologically confirmed hemangiosarcoma were evaluated by thoracic radiography for metastatic disease. All dogs had histopathologic examinations of the lungs within two weeks of thoracic radiography. Fourteen dogs had histopathologic evidence of pulmonary hemangiosarcoma; metastatic disease was detected radiographically in eleven of these dogs. The most common radiographic pattern was that of poorly defined small coalescing nodules (8 dogs); other radiographic patterns included well-circumscribed nodules (3 dogs) and alveolar infiltrates secondary to hemorrhage (2 dogs). Differential diagnoses for diffuse, poorly defined, coalescing pulmonary opacities should include hemangiosarcoma in addition to edema, lymphoma, systemic mycoses, fibrosis, allergy, toxicosis, and carcinomas.     

Spontaneous midlobar lung lobe torsion in a 2-year-old Newfoundland

A 2-year-old, intact male Newfoundland was presented for evaluation of a 1- to 2-day history of coughing, retching, and progressive lethargy. Thoracic radiographs demonstrated right-sided pleural effusion and lobar vesicular emphysema. An exploratory thoracotomy revealed midlobar torsion of the right caudal lung lobe. A partial lung lobectomy was performed, and following surgery, the dog recovered without complications. Lung lobe torsions in dogs typically occur at the hilus of the affected lung lobe. This report documents that midlobar lung lobe torsions occur in dogs and should be considered as a differential diagnosis in cases of lobar vesicular emphysema and pleural effusion.     

Clinical signs, clinicopathological findings, etiology, and outcome associated with hemoptysis in dogs: 36 cases (1990-1999)

Hemoptysis, the expectoration of blood or bloody mucus from the respiratory tract at or below the larynx, was retrospectively evaluated in 36 dogs. Cough, tachypnea, and dyspnea were common historical and physical examination signs. Anemia was documented in 11 dogs, but was severe in only one dog. Other clinicopathological findings reflected the underlying diseases. All thoracic radiographs obtained were abnormal; alveolar and interstitial patterns were most common. Diseases predisposing to hemoptysis included bacterial bronchopneumonia (n=7), neoplasia (n=5), trauma (n=5), immune-mediated thrombocytopenia (n=4), heartworm disease (n=4), rodenticide poisoning (n=3), lung-lobe torsion (n=1), left-sided congestive heart failure (n=1), pulmonary hypertension (n=1), and foreign-body pneumonia (n=1). Four additional dogs had more than one underlying disease process. Nine dogs were either euthanized or died in the hospital during the initial visit. While at least half of the 27 dogs discharged went on to completely recover, five dogs discharged were known to have either died or been euthanized as a result of their disease in <6 months.     

Surgical and nonsurgical management of and selected risk factors for spontaneous pneumothorax in dogs: 64 cases (1986-1999)

OBJECTIVE: To compare results of surgical versus nonsurgical treatment of spontaneous pneumothorax in dogs. DESIGN: Retrospective study. ANIMALS: 64 dogs with pneumothorax without any history of antecedent trauma. PROCEDURE: Information on signalment, thoracic radiographic findings, treatment, histologic findings, and outcome was obtained from the medical records. Signalment of affected dogs was compared with signalment of a control population of 260 dogs examined by the emergency service for reasons other than pneumothorax during the study period. RESULTS: Siberian Huskies were overrepresented in the case population, compared with the control population of dogs examined by the emergency service for other reasons. Twenty-eight dogs were treated without surgery (ie, thoracocentesis or tube thoracostomy with or without cage rest), and 36 were treated with surgery. Information regarding final outcome was available for 33 dogs treated with surgery (median follow-up time, 485 days) and 15 dogs treated without surgery (median follow-up time, 366 days). Dogs that underwent surgery had significantly lower recurrence (1/30) and mortality (4/33) rates, compared with dogs treated without surgery (6/12 and 8/15, respectively). A definitive diagnosis was obtained for 38 dogs, including 34 of 36 dogs undergoing surgery; 26 had bullous emphysema and 4 had neoplasia. Two dogs developed spontaneous pneumothorax secondary to migration of plant foreign bodies. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that recurrence and mortality rates for dogs with spontaneous pneumothorax managed surgically were significantly lower than rates for dogs managed by nonsurgical means alone. Early surgical intervention is recommended for definitive diagnosis and treatment of dogs with spontaneous pneumothorax.     

Diagnostic and prognostic value of endothelin-1 plasma concentrations in dogs with heart and respiratory disorders

The endothelin-1 (ET-1) plasma concentration was measured in dogs with spontaneous cardiac or respiratory diseases. Plasma samples were obtained from 76 healthy control dogs and 73 dogs, of which 58 were suffering from heart disease and 15 were suffering from respiratory disease. Dogs were evaluated using echocardiography, thoracic radiography, biochemical evaluation and a radioimmunoassay for ET-1. ET-1 plasma concentrations were significantly higher in dogs with spontaneous cardiac or respiratory diseases (mean [se] 5.3 [0.3] and 5.3 [0.6] pg/ml, respectively) than in healthy dogs (1.9 [0.1] pg/ml) (P<0.0001). ET-1 plasma concentrations increased with the class of heart failure (International Small Animal Cardiac Health Council classification) (P<0.0001) and with the severity of pulmonary disorders. ET-1 plasma concentrations were positively correlated with the extent of systolic pulmonary hypertension measured by Doppler echocardiography (P<0.05; r=0.75) and with the clinical outcome of dogs with respiratory disease. Evaluation of the ET-1 plasma concentration allowed differentiation between heart and respiratory disorders in dogs exhibiting clinical signs at exercise, but not in patients exhibiting clinical signs at rest.