Benoît Ghaye

Comparison of automated 4-chamber cardiac views versus axial views for measuring right ventricular enlargement in patients with suspected pulmonary embolism

PURPOSE Compare the right ventricle to left ventricle (RV/LV) diameter ratio obtained from axial pulmonary CT angiograms (CTPA) with those derived from automatically generated 4-chamber (4-CH) reformats in patients with suspected pulmonary embolism (PE). METHODS In this institutional review board-approved study we included 120 consecutive non ECG-gated CTPA from 3 institutions (mean age 60 ± 16 years; 71 women). Twenty 64-slice CTPA with PE and 20 without PE were selected per institution. For each patient the RV/LV diameter ratio was obtained from both axial CTPA images and automatically generated 4-CH reformats. Measurements were performed twice in two separated sessions by 2 experienced radiologists and 2 residents. The differences between the measurements on both views were evaluated. RESULTS The 4-CH view was successfully obtained in 113 patients. The mean axial and 4-CH diameter ratios were comparable for three of the four readers (p = 0.56, p = 0.13, p = 0.08). Although the mean diameters (1.0 and 1.03 respectively) for one resident were significantly different (p = 0.013), the difference of 0.03 seems negligible in clinical routine. Three readers achieved equally high intra-reader agreements with both measurements (ICCs of 0.94, 0.95 and 0.96), while one reader showed a different variability with ICCs of 0.96 for the axial view and 0.91 for the 4-CH view. The inter-reader agreement was equally high for both measurement types with ICCs of 0.95 and 0.94, respectively. CONCLUSION In patients with suspected PE, RV/LV diameters ratio can be measured with the same reproducibility and accuracy using an automatically generated 4-CH view compared to the axial view.

Imaging after radiation therapy of thoracic tumors.

Radiation-induced lung disease (RILD) is frequent after therapeutic irradiation of thoracic malignancies. Many technique-, treatment-, tumor- and patient-related factors influence the degree of injury sustained by the lung after irradiation. Based on the time interval after the completion of the treatment RILD presents as early and late features characterized by inflammatory and fibrotic changes, respectively. They are usually confined to the radiation port. Though the typical pattern of RILD is easily recognized after conventional two-dimensional radiation therapy (RT), RILD may present with atypical patterns after more recent types of three- or four-dimensional RT treatment. Three atypical patterns are reported: the modified conventional, the mass-like and the scar-like patterns. Knowledge of the various features and patterns of RILD is important for correct diagnosis and appropriate treatment. RILD should be differentiated from recurrent tumoral disease, infection and radiation-induced tumors. Due to RILD, the follow-up after RT may be difficult as response evaluation criteria in solid tumours (RECIST) criteria may be unreliable to assess tumor control particularly after stereotactic ablation RT (SABR). Long-term follow-up should be based on clinical examination and morphological and/or functional investigations including CT, PET-CT, pulmonary functional tests, MRI and PET-MRI.

Intravascular tumour embolism from chondrosarcoma

A 48-year-old woman with a history of sternal chondrosarcoma that had been completely resected 3 years previously presented with a 7-month history of cough and progressive dyspnoea. On admission she had blood oxygen saturation of 88%. Pulmonary CT angiography showed a large tumour embolus in the main pulmonary artery bifurcation that extended into the left pulmonary artery and all the left lobar and segmental arterial branches and caused a large left lower lobe parenchymal consolidation (fi gure). Percutaneous transthoracic biopsy of the consolidation showed metastatic chondrosarcoma. She underwent a left pneumonectomy. Macroscopic examination of the resected lung (fi gure) showed a translucent myxoid tissue fi lling the pulmonary arteries in an arboreous pattern. Microscopic analysis confi rmed that the metastatic chondrosarcoma was confi ned to the vasculature, even inside the parenchymal consolidation. The patient died 4 months later from respiratory insuffi ciency from right-sided pleural and pulmonary infection associated with rapid metastatic spread to the right lung. Pulmonary intravascular tumour embolism is often underdiagnosed at imaging; it is reported in 4–30% of all patients with malignancy on post-mortem examination. It is most common in cancers of the kidney, liver, breast, and lung. Chondrosarcomas are the third most common primary bone malignancy. They often metastasise to the lung parenchyma, but intravascular pulmonary tumour embolism has rarely been reported in chondrosarcoma. Distribution depends on the size of the initial tumour embolus. Small tumour emboli initially lodge distally and propagate towards the centre, gradually aff ecting larger pulmonary vessels, whereas larger tumour aggregates that embolise in more proximal vessels spread both centrally and peripherally. The clinical signs of pulmonary tumour embolism are variable, and often mimic those of acute or chronic pulmonary thromboembolism; unlike thrombo emboli, tumour emboli typically continue to grow despite anticoagulation. Pulmonary tumour embolism can show various patterns on chest CT (fi gure). It can present with a tree-in-bud pattern—a pattern that is more commonly seen in other diseases such as bronchiolar infl ammation or infection— when small tumour emboli cause fi lling and dilatation of the small peripheral centrilobular pulmonary arteries, occasionally leading to a pulmonary infarct. The most characteristic appearance of tumour embolism is enlargement of more central beaded pulmonary arteries, caused by larger tumour emboli. Extensive dissemination can also result in parenchymal consolidation, a cause that should be considered in a patient with a known malignancy.

Iatrogenic cardiac perforation due to pacing lead displacement: Imaging findings

PURPOSE Cardiac perforations due to pacing and implantable defibrillator lead displacement are rare and their detection may be difficult. The goal of this study was to review the clinical and imaging presentation of cardiac perforation related to pacing lead displacement. PATIENTS AND METHODS The clinical and imaging files of four patients (two men and two women) who experienced cardiac perforation related to pacing lead displacement were reviewed. The four patients were investigated in our radiology department over a 24-month-period. RESULTS Two patients had clinical symptoms at the time lead displacement was detected and the other two were free of symptoms. In all patients, lead displacement was visible on imaging examinations in retrospect but was not detected prospectively. CONCLUSION Radiologists should pay attention to the position of the tips of the leads on chest X-ray and CT, even late after the implantation and in asymptomatic patients.

Severe COPD exacerbation: CT features.

Abstract Objective: To describe CT features associated with severe exacerbations of Chronic Obstructive Pulmonary Disease (COPD). Materials and Methods: In this prospective ethical-committee-approved study, 44 COPD patients (34 men, 10 women, age range 49–83 years) who provided written informed consent were included at the time of hospital admission for severe exacerbation. Pulmonary function tests (PFT) and chest CT scans were performed at admission and after resolution of the episode following a minimum of 4 weeks free of any acute symptom. For each CT scan, two radiologists independently scored 15 features in each lobe and side. CT features and PFT results were compared for exacerbation and control through Mac-Nemar tests and paired t-tests, respectively. Results: Forced expiratory volume in 1 second and vital capacity improved significantly after exacerbation (p = 0.023 and 0.012, respectively). Bronchial wall thickening and lymphadenopathy were graded significantly higher at exacerbation than at control by both readers (p ranging from < 0.001 to 0.028). Other CT features were not observed during exacerbation, or were so only by one reader (p ranging from < 0.001 to 0.928). Conclusion: Only lymphadenopathy and bronchial wall thickening are CT features associated with severe COPD exacerbation, respectively in 25% and 50% of patients. Our findings do not advocate a role for CT in the routine work-up of patients with severe COPD exacerbation.

Asymptomatic Late Migration of an Atrial Pacemaker Lead into the Right Lung

This report illustrates an unusual case of asymptomatic late cardiac perforation by an atrial pacemaker lead into the right lung. In the present case, the lead was explanted by simple manual traction through the device pocket without any complications.

Extramedullary haemopoiesis and spinal cord compression.

Department of Medical Imaging, Universite Catholique de Louvain, Cliniques Universitaires St-Luc Brussels, Belgium (Prof E E Coche MD), Department of Medicial Imaging, Universite catholique de Louvain, Cliniques Universitaires St-Luc, Brussels, Belgium (C A Dragean MD, L Duquesne MD, B Ghaye MD), Department of Pathology, Universite catholique de Louvain, Cliniques Universitaires St-Luc, Brussels, Belgium (I Theate MD)

Value of the “spine sign” on lateral chest views

OBJECTIVE To determine the performance of the spine sign in detecting lower chest abnormalities in the lateral view. METHODS This retrospective study included 200 patients who had undergone lateral view and CT scans of the chest within 1 week. Two radiologists independently read the lateral views, and a third radiologist, blinded to the aim of the study, read the scans. The spine sign was considered as positive if the progressive increase in lucency of the vertebral bodies was altered. Interreader agreement was calculated through k-statistics. Sensitivity, specificity, positive- and negative-predictive values, and accuracy were calculated compared with CT. RESULTS Agreements between readers ranged from 0.12 to 0.68. Positive spine sign could appear in two ways: absent or inversed progressive increase in lucency of the vertebral bodies. Sensitivity, specificity, positive- and negative-predictive values, and accuracy were, respectively, 60% and 70%; 64% and 84%; 91% and 97%; 19% and 29%; and 61% and 72% for each reader (p-value ranging from 0.026 to 0.196). Abnormalities most frequently associated with positive spine sign were plate-like atelectasis, ground-glass opacity, pleural effusion and consolidation. CONCLUSION The spine sign can present as an absent or inversed progressive increase in lucency of the vertebral bodies. It has a moderate sensitivity but a good positive-predictive value, so it can be useful especially when it appears as inversed progressive increase in lucency of the vertebral bodies to detect various abnormalities usually identifiable on chest radiographs. ADVANCES IN KNOWLEDGE On lateral chest radiographs, the spine sign is useful to detect lower chest abnormalities and is related to various underlying abnormalities and is, per se, non-specific.

Unexpected 'pulmonary hypertension' in a patient with granulomatosis with polyangiitis.

A 62-year-old woman presented with increasing dyspnoea for 3 months. She had a known history of granulomatosis with polyangiitis (GPA) that was diagnosed upon biopsy of an interauricular septal mass revealed by a third-degree AV block 6 years earlier leading to implantation of a pacemaker. At current admission, transthoracic echocardiography showed a maximal systolic pressure gradient of 65 mmHg between the right …

Re-expansion pulmonary oedema

A 46-year-old man presented to the emergency department with moderate dyspnoea and a 4-day history of cough. His medical history also included alcoholic cirrhosis with portal hypertension and ascites. On admission, a chest x-ray showed complete white-out of the right hemithorax with contralateral mediastinal deviation compatible with a large pleural effusion—presumed to be hepatic hydrothorax (figure). A chest drain was inserted into the right pleural cavity under ultrasound guidance and 2 L of clear fluid were rapidly drained over approximately 2 min. A further chest x-ray taken the day after admission showed a large right hydropneumothorax and a partly collapsed right lung with consolidation of the upper lobe (figure). A second larger chest drain was inserted to ensure adequate drainage. A CT chest scan was then done to rule out any underlying lung disease; this showed near-complete resolution of the right hydropneumothorax and patchy consolidation, ground glass opacities, and septal thickening throughout the right lung—mainly in the upper and middle lobes (figure). Based on the clinical and radiological findings, a diagnosis of re-expansion pulmonary oedema was made. The patient recovered completely after 2 days of supportive treatment and a further chest x-ray showed clear lung fields bilaterally (figure). The total volume drained was calculated to be 5·5 L. Pleural fluid analyses showed a transudate with negative culture and cytology. Re-expansion pulmonary oedema is an uncommon complication occurring in less than 1% of cases where a lung has been rapidly re-expanded after being passively collapsed by a large pleural effusion or a pneumothorax. The precise pathophysiology underlying re-expansion pulmonary oedema has not been clearly established, but alterations of vascular permeability and hydrostatic mechanisms are thought to be involved. Risk factors for the complication include pulmonary collapse for longer than 1 week, younger age, and the rapid removal of a large amount of pleural fluid over a short time period which is why the recommended rate of removal of 1–2 L every 2 h should not be exceeded. Treatment is generally conservative and supportive.