[Mediastinal haematoma: A little known complication of ultrasound-guided trans-bronchial lymph node aspiration (EBUS-TBNA)]

INTRODUCTION

Endobronchial ultrasound-guided trans-bronchial needle aspiration (EBUS-TBNA) has emerged as a minimally invasive, highly accurate technique for sampling intrathoracic lymph nodes. The complication rate after EBUS-TBNA is estimated at between 0.22% to 1.44%. Analysis of the different series of EBUS-TBNA reveals that mediastinal haematoma has not been described as a complication.

CASE REPORT

We describe the case of a 65-year-old-man who underwent an EBUS-TBNA of a subcarinal lymph node. Few days later the patient presented with haemoptysis of average amount associated with a haematoma in the subcarinal area seen on CT-scan. It was suggested that puncture of a bronchial artery occurred during passage of the needle. This complication occurred during the change from treatment by low molecular weight heparin to antivitamine K. The patient was monitored in the intensive care unit and received medical treatment only.

CONCLUSIONS

This patient developed a complication after an EBUS-TBNA that is rarely described and probably under diagnosed. This complication occurred during the change between two anticoagulant treatments, which requires special attention in this particular context.

CT-texture analysis of subsolid nodules for differentiating invasive from in-situ and minimally invasive lung adenocarcinoma subtypes

PURPOSE

The purpose of this study was to evaluate the usefulness of computed tomography-texture analysis (CTTA) in differentiating between in-situ and minimally-invasive from invasive adenocarcinomas in subsolid lung nodules (SSLNs).

MATERIAL AND METHODS

Two radiologists retrospectively reviewed 49 SSLNs in 44 patients. There were 27 men and 17 women with a mean age of 63±7 (SD) years (range: 47-78years). For each SSLN, type (pure ground-glass or part-solid) was assessed by consensus and CTTA was conducted independently by each observer using a filtration-histogram technique. Different filters were used before histogram quantification: no filtration, fine, medium and coarse, followed by histogram quantification using mean intensity, standard deviation (SD), entropy, mean positive pixels (MPP), skewness and kurtosis.

RESULTS

We analyzed 13 pure ground-glass and 36 part-solid nodules corresponding to 16 adenocarcinomas in-situ (AIS), 5 minimally invasive adenocarcinomas (MIA) and 28 invasive adenocarcinomas (IVA). At uni- and multivariate analysis CTTA allowed discriminating between IVAs and AIS/MIA (P<0.05 and P=0.025, respectively) with the following histogram parameters: skewness using fine textures and kurtosis using coarse filtration for pure ground-glass nodules, and SD without filtration for part-solid nodules.

CONCLUSION

CTTA has the potential to differentiate AIS and MIA from IVA among SSLNs. However, our results require further validation on a larger cohort.

[Predictive factors of complications during CT-guided transthoracic biopsy]

INTRODUCTION

CT-guided transthoracic core-needle biopsy (TTNB) is frequently used for the diagnosis of lung nodules. The aim of this study is to describe TTNBs' complications and to investigate predictive factors of complications.

METHODS

All consecutive TTNBs performed in three centers between 2006 and 2012 were included. Binary logistic regression was used for multivariate analysis.

RESULTS

Overall, 970 TTNBs were performed in 929 patients. The complication rate was 34% (life-threatening complication in 6%). The most frequent complications were pneumothorax (29% included 4% which required chest-tube) and hemoptysis (5%). The mortality rate was 0.1% (n=1). In multivariate analysis, predictive factor for a complication was small target size (AOR=0.984; 95% CI [0.976-0.992]; P<0.001). This predictive factor was also found for occurrence of life-threatening complication (AOR=0.982; [0.965-0.999]; P=0.037), of pneumothorax (AOR=0.987; [0.978-0.995]; P=0.002) and of hemoptysis (AOR=0.973; [0.951-0.997]; P=0.024).

CONCLUSION

One complication occurred in one-third of TTNBs. The proportion of life-threatening complication was 6%. A small lesion size was predictive of complication occurrence.

Lung adenocarcinomas: correlation of computed tomography and pathology findings

Adenocarcinoma is the most common histologic type of lung cancer. Recent lung adenocarcinoma classifications from the International Association for the Study of Lung cancer, the American Thoracic Society and the European Respiratory Society (IASLC/ETS/ERS, 2011) and World Health Organization (WHO, 2015) define a wide range of adenocarcinoma types and subtypes featuring different prognosis and management. This spectrum of lesions translates into various CT presentations and features, which generally show good correlation with histopathology, stressing the key role of the radiologist in the diagnosis and management of those patients. This review aims at helping radiologists to understand the basics of the up-to-date adenocarcinoma pathological classifications, radio-pathological correlations and how to use them in the clinical setting, as well as other imaging-related correlations (radiogenomics, quantitative analysis, PET-CT).

Personalized chemotherapy of lung cancer: What the radiologist should know

Lung cancer is the leading cause of deaths due to cancer in France. More than half of lung cancers are discovered at an advanced-stage. New anticancer treatment strategies (i.e., the so-called personalized or targeted therapy) have recently been introduced and validated for non-small-cell lung cancer (NSCLC), in addition to or in association with standard chemotherapy. Personalized therapy includes tyrosine kinase inhibitors (TKIs), antiangiogenic treatments and immunotherapy. Because these treatments may be responsible for atypical thoracic adverse effects and responses as compared to standard chemotherapy, RECIST 1.1 criteria may be inadequate to evaluate the responses to these agents. The goal of this article was to review personalized treatment strategies for NSCLC, to consider the therapy-specific responses and thoracic complications induced by these new therapeutic agents and finally to discuss future directions for the personalized assessment of tumor response.

From randomized trials to the clinic: is it time to implement individual lung-cancer screening in clinical practice? A multidisciplinary statement from French experts on behalf of the French intergroup (IFCT) and the groupe d'Oncologie de langue francaise (GOLF)

Background

Despite advances in cancer therapy, mortality is still high except in early-stage tumors, and screening remains a challenge. The randomized National Lung Screening Trial (NLST), comparing annual low-dose computed tomography (LDCT) and chest X-rays, revealed a 20% decrease in lung-cancer-specific mortality. These results raised numerous questions. The French intergroup for thoracic oncology and the French-speaking oncology group convened an expert group to provide a coherent outlook on screening modalities in France.

Methods

A literature review was carried out and transmitted to the expert group, which was divided into three workshops to tackle specific questions, with responses presented in a plenary session. A writing committee drafted this article.

Results

The multidisciplinary group favored individual screening in France, when carried out as outlined in this article and after informing subjects of the benefits and risks. The target population involves subjects aged 55–74 years, who are smokers or have a 30 pack-year smoking history. Subjects should be informed about the benefits of quitting. Screening should involve LDCT scanning with specific modalities. Criteria for CT positivity and management algorithms for positive examinations are given.

Conclusions

Individual screening requires rigorous assessment and precise research in order to potentially develop a lung-cancer screening policy.

Imaging of tumors of the trachea and central bronchi

Tumors of the trachea and central bronchi can be benign or malignant. Clinical presentation may be confusing, particularly in benign tumors that can be misdiagnosed as asthma or chronic bronchitis. Chest radiography has many limitations and is often considered unremarkable in patients with tumors of the central airways; therefore, multidetector CT (MDCT) has become the most useful noninvasive method for diagnosing and assessing the central airways. The purpose of this article is to provide a review of imaging of the tumors of the trachea and central bronchi. We emphasize the crucial role of MDCT and postprocessing techniques in assessing neoplasms of the central airways.

CT characteristics of resolving ground-glass opacities in a lung cancer screening programme

PURPOSE

This study aimed at evaluating the computed tomography (CT) characteristics of resolving localized ground-glass opacities (GGOs) in a screening programme for lung cancer.

MATERIAL AND METHODS

280 patients at high-risk for lung cancer (221 men, 59 women; mean age, 58.6 years), divided into four groups (lung cancer history (n = 83), head and neck cancer history (n = 63), symptomatic (n = 88) and asymptomatic (n = 46) cigarette smokers), were included in a prospective trial with annual low-dose CT for lung cancer screening. We retrospectively reviewed all localized GGOs, analyzed the CT characteristics on initial CT scans and changes during follow-up (median 29.1 months). Variables associated with resolution of GGOs were tested using chi-square or Mann-Whitney tests.

RESULTS

A total of 75 GGOs were detected in 37 patients; 54.7% were present at baseline and 45.3% appeared on annual CT. During follow-up, 56.2% persisted and 43.8% disappeared. The resolving localized GGOs were significantly more often lobular GGOs (p = 0.006), polygonal in shape (p = 0.02), mixed (p = 0.003) and larger (p < 0.0001) than non-resolving localized GGOs.

CONCLUSION

Localized GGOs are frequent and many disappeared on follow-up. CT characteristics of resolving GGOs show significant differences compared to persistent ones. This study emphasizes the importance of short-term CT follow-up in subjects with localized GGOs.

Imaging of tumors of the trachea and central bronchi

Tumors of the trachea and central bronchi can be benign or malignant. Clinical presentation may be confusing, particularly in benign tumors that can be misdiagnosed as asthma or chronic bronchitis. Chest radiography has many limitations and is often considered unremarkable in patients with tumors of the central airways; therefore, multidetector CT (MDCT) has become the most useful noninvasive method for diagnosing and assessing the central airways. The purpose of this article is to provide a review of imaging of the tumors of the trachea and central bronchi. We emphasize the crucial role of MDCT and postprocessing techniques in assessing neoplasms of the central airways.

Unusual cystic presentation of pulmonary nodular amyloidosis associated with MALT-type lymphoma

The case reported herein consists of nodular pulmonary amyloidosis presenting with unusual cystic radiological features which reveal a pulmonary localisation of an extranodal marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue (MALT lymphoma). The present case is the first to report a radiological presentation of nodular pulmonary amyloidosis in the absence of Sjögren's syndrome. Although transthoracic fine-needle biopsy was helpful for the diagnostic of amyloidosis, final diagnosis of associated MALT-type lymphoma required an open lung biopsy. This emphasises the importance of performing surgical investigations in pulmonary nodular amyloidosis in order to depict the presence of underlying lung tumours or lymphoproliferative disorders.

Non-conform diagnostic management of pulmonary embolism suspected patients is responsible for a higher risk of thrombotic event occurrence

The aim of this 3-month follow-up prospective pragmatic study was to evaluate the implementation of a pulmonary embolism (PE) diagnostic strategy in clinical practice. One thousand and one hundred thirty-four consecutive in- and outpatients with clinically suspected PE were enrolled into a sequential diagnostic algorithm in which vascular medical unit plays a pivotal role in advising physicians and suggesting the most appropriate tests according to the diagnostic algorithm. In this observational study, patients that followed the proposed work-up were attributed to a so-called "conform group". Patients in whom diagnostic work-up was not according to protocol were attributed to a "non-conform group". Nine hundred and ninety-seven patients (87.9%) had a conform work-up, and 137 patients a non-conform work-up according to the proposed diagnostic algorithm. The non-conform work-up directly increased in relation to the age of the referred patients. PE was ruled out in 907 (80%) patients of whom 787 (86.8%) were in the conform group. Of the 797 patients who did not receive anticoagulant drugs, follow-up was obtained in 792 (99.4%). Among these patients, the incidence of acute thromboembolic events during the 3-month follow-up period was different in the group of patients that had a conform work-up (1%, [95% CI, 0.5-2.1%]) from the non-conform group patients (4.5%, [95% CI, 2-10.2%]. Therefore patients from the non-conform group have an independent increased risk to develop a thromboembolic event during the follow-up, adjusted odds ratio 3.3 [1.1-10, 95% CI]. Therefore we demonstrated that a non-conform diagnostic management strategy is associated with a higher risk of thrombotic event occurrence.

Pulmonary involvement by Niemann-Pick disease. A report of six cases

AIMS

Although pulmonary involvement is a known cause of morbidity in Niemann-Pick disease, histological features in the lung are not well characterized. The purpose of this study is to document the histological features seen in pulmonary involvement by types B and C Niemann-Pick disease and to correlate them with clinical and imaging data.

METHODS AND RESULTS

Surgical lung biopsies from six patients (four with type B and two with type C disease) were reviewed and all showed diffuse endogenous lipid pneumonia, with lesser involvement of the interstitium by fibrosis and foamy macrophage accumulation. In type B disease only, there was also fine cytoplasmic vacuolation within the cytoplasm of ciliated epithelial cells. Neither disease showed foamy changes within pneumocytes. One patient had a bronchial cast removed on whole lung lavage. Electron microscopy showed abnormal lamellar inclusions within lysosomes of affected cells in type B disease. In patients with type C disease, biopsies were undertaken as part of investigations into acute respiratory failure in the context of multiorgan systemic presentation. Three patients with type B disease had clinical disease limited to the lung, all adults (mean age of 40 years) with unexplained diffuse parenchymal lung disease and mainly ground-glass shadowing on high-resolution computed tomography.

CONCLUSIONS

Niemann-Pick disease should be considered for any patient with unexplained diffuse endogenous lipid pneumonia, even when disease is limited to the lungs and presentation is during adulthood.

Adenocarcinoma of the lung mimicking inflammatory lung disease with honeycombing

Pulmonary adenocarcinoma of the lung and its variants are well-defined entities, since the recent WHO classification of lung tumours. However, scant descriptions have been allocated to associated stromal changes, such as prominent inflammation and fibrosis, which can overshadow a tumoral proliferation and masquerade as a benign reactive process and this has not been recognised as a histopathological variant. The case of a 72-yr-old farmer who presented a multifocal well-differentiated adenocarcinoma that mimicked honeycomb lung with bronchiolectasis radiologically, on computed tomography scan and histologically at open lung biopsy, is reported. Histological pitfalls in the biopsy were represented by mild atypical cuboidal or columnar epithelial cells lining bronchiolar structures resembling florid bronchiolar metaplasia in a background of extensive fibrosis and inflammation, features that mimicked inflammatory honeycombing. However, histological analysis of the surgical resection of the main lesion, performed because of a clinical alteration of the patient, confirmed the diagnosis of multifocal adenocarcinoma of mixed subtype. A monomorphic proliferation of clear cells, lack of associated ciliated or squamous cells and presence of significant cytologic atypia gave a diagnosis of malignancy. This case illustrates how inflammatory and fibrotic changes may conceal a correct diagnosis of carcinoma and emphasises the importance of adequate sampling in such cases.

Follow-up after stent insertion in the tracheobronchial tree: role of helical computed tomography in comparison with fiberoptic bronchoscopy

The aim of this study was to compare helical CT with fiberoptic bronchoscopy findings to appraise the medium-term results of proximal-airways stenting. Twenty-five patients with 28 endobronchial metallic stents inserted for local advanced malignancy ( n=13) or benign diseases ( n=12) underwent follow-up CT from 3 days to 50 months (mean 8 months). All studies were obtained using helical CT with subsequent multiplanar reformation and three-dimensional reconstruction including virtual bronchoscopy. The location, shape, and patency of stents and adjacent airway were assessed. The results of CT were compared with the results of fiberoptic bronchoscopy obtained with a mean delay of 2.5 days (SD 9 days) after CT scan. Twelve stents (43%) remained in their original position, patent and without deformity. Sixteen stents were associated with local complications: migration ( n=6); external compression with persistent stenosis ( n=4); local recurrence of malignancy ( n=4); fracture ( n=1); and non-congruence between the airway and the stent ( n=1). The CT demonstrated all the significant abnormalities demonstrated at fiberoptic bronchoscopy except two moderate stenoses (20%) related to granulomata at the origin of the stent. Ten of 14 stents inserted for benign conditions were without complications as compared with 2 of 14 in malignant conditions ( p=0.008). Computed tomography is an accurate noninvasive method for evaluating endobronchial stents. The CT is a useful technique for follow-up of patients who have undergone endobronchial stenting.

Thoracic lymphangiectasis presenting with chyloptysis and bronchial cast expectoration

A 70-year-old man with recurrent undiagnosed episodes of bronchial cast expectoration and pulmonary infiltrates on chest radiography for 15 years is described. The diagnosis of chyloptysis was established by chemical analysis of the bronchial aspiration. We emphasize the radiological findings of this rare observation. The CT-associated lymphangiography showed mediastinal lymphangiectasis with retrograde opacification of mediastinal and hilar lymph nodes as well as submucosal lymphatic vessels protruding into the lumen of the tracheo-bronchial tree without evidence of thoracic duct obstruction as well as a "crazy-paving appearance." Congenital incompetence of the valves of the lymphatic vessels originating from the thoracic duct is held to be the cause. Chyloptysis and pulmonary lymphatic disorder should be sought in cases of bronchial cast expectoration.

Virtual tools for imaging of the thorax

Helical computed tomography (HCT) allows for volume acquisition of the entire thorax during a single apnoea. Combination of HCT acquisition with synchronous vascular enhancement gives rise to HCT angiography (HCTA). In the last decade, HCT and HCTA have revolutionized the diagnosis of thoracic diseases, modifying many diagnostic algorithms. Because HCT provides for a true volume acquisition free of respiratory misregistration, three-dimensional (3D) rendering techniques can be applied to HCT acquisitions. As these 3D rendering techniques present the HCT information in a different format to the conventional transaxial CT slices, they can be summarized as virtual tools. The purpose of this review is to give the readers the most important technical aspects of virtual tools, to report their application to the thorax, to answer clinical and scientific questions, and to stress their importance for patient management, clinical decision making, and research.

Helical CT with Multiplanar and Three-Dimensional Reconstruction of Nonneoplastic Abnormalities of the Trachea

Helical CT is being increasingly used for the evaluation of suspected tracheal diseases. Although nonneoplastic and noninfectious diseases of the trachea are rare, their appearance on CT images may be highly suggestive of the diagnosis. High quality multiplanar and 3D reconstructions including 3D surface-shaded display and virtual bronchoscopy are helpful to characterize tracheal abnormalities and to demonstrate the location and extent of the diseases.

Benign abnormalities and carcinoid tumors of the central airways: diagnostic impact of CT bronchography

OBJECTIVE

The purpose of this retrospective study was to determine the added diagnostic value, if any, of CT bronchography for the detection and characterization of benign abnormalities and typical carcinoid tumors of the central airways.

MATERIALS AND METHODS

We used bronchoscopy and helical CT to examine 238 bronchial sections in 28 patients with 32 bronchial abnormalities and in five patients with normal bronchoscopy results. Postprocessing consisted of CT bronchography based on surface rendering. Images were interpreted independently by two observers (a radiologist and a pneumonologist) who were not informed of the bronchoscopy results. After initial interpretation of axial CT scans, the observers analyzed the axial CT scans with CT bronchograms. Results were evaluated for gain in diagnostic accuracy and in confidence.

RESULTS

Mean sensitivity for detection of abnormal bronchial sections was 89% (range, 87-90%) for axial CT and 92% (range, 90-94%) for axial CT with CT bronchography (not significant). Mean specificity of both approaches exceeded 99%. A correct diagnosis of the nature of the bronchial abnormalities was proposed for 68% of the cases in which axial CT was used alone and in 76% in which both axial CT and CT bronchography were used (not significant). The addition of CT bronchography significantly increased the confidence of the pneumonologist in the diagnoses.

CONCLUSION

Axial CT remains the technique of choice to detect and characterize benign abnormalities of the airways. CT bronchography provides little diagnostic gain but increases the confidence of chest physicians in the interpretation of CT scans for the assessment of benign abnormalities and typical carcinoids of the central airways.

Paradoxical emboli: demonstration using helical computed tomography of the pulmonary artery associated with abdominal computed tomography

We report the case of a 60-year-old woman with a recent history of a cerebrovascular accident. Because of clinical suspicion of pulmonary embolism and negative Doppler ultrasound findings of the lower limbs, spiral computed tomography of the pulmonary artery was performed and demonstrated pulmonary emboli. We emphasize the role of computed tomography of the abdomen, performed 3 min after the thoracic acquisition, which showed an unsuspected thrombus within the abdominal aorta and the left renal artery with infarction of the left kidney. Paradoxical embolism was highly suspected on computed tomography data and confirmed by echocardiography which demonstrated a patent foramen ovale.

Obstructive sleep apnea syndrome: hooked appearance of the soft palate in awake patients--cephalometric and CT findings

PURPOSE

To determine whether a hooked appearance of the soft palate can be seen in awake patients with snoring with or without obstructive sleep apnea syndrome (OSAS) on cephalometric radiographs and computed tomographic (CT) scans.

MATERIALS AND METHODS

One hundred thirty-one patients with snoring underwent cephalometric radiography, with which the posterior airway space, soft palate length and width, and distance between the hyoid bone and mandibular plane were measured, and/or pharyngeal CT, with which the luminal areas of the airway at the naso-, oro-, and hypopharyngeal levels were measured.

RESULTS

Of the 131 patients, 96 had OSAS, and 35 had snoring. Nine of 96 patients with OSAS had soft palate hooking on awake pharyngeal CT or cephalometric images. No patient with snoring alone had hooking. Patients with hooking had a larger posterior airway space than did patients with OSAS without hooking (P = .05), and an enlarged (> or = 15-mm) posterior airway space was more frequent in patients with hooking (eight of nine patients) than in those without hooking (34 of 87) (P < .01). Oropharyngeal and hypopharyngeal areas were significantly larger in patients with hooking than in patients without hooking or in patients with snoring (P < or = .04).

CONCLUSION

Cephalometric radiography and CT can demonstrate hooking of the soft palate in awake patients. This finding indicates a high risk for OSAS.

Haemoptysis associated with pulmonary varices: demonstration using computed tomographic angiography

A 67 yr old female with mitral stenosis presented with an acute haemoptysis caused by the rupture of pulmonary varices. Chest radiography and bronchoscopy showed nonspecific abnormalities. The diagnosis of this rare but potentially lethal complication was made using computed tomographic angiography with three-dimensional volume rendering.

[CT x-ray evaluation of abdominal and pelvic veins in patients suspected of acute pulmonary embolism with negative Doppler sonography]

PURPOSE

To address prospectively the potential of CT of the abdomen and pelvis to demonstrate deep vein thrombosis in patients suspected of acute pulmonary embolism and investigated with helical CT of the pulmonary arteries.

MATERIAL AND METHODS

197 patients presenting non-diagnostic scintigraphy and negative Doppler US of lower limbs and IVC were included. They had helical CT of the pulmonary arteries (5mm collimation, 1:1 pitch, reconstruction every 2.5 mm, injection of 120 mL of contrast media at a rate of 3 mL/sec). Ninety seconds after the end of the thoracic acquisition, abdominal and pelvic CT were acquired (7 mm collimation every 12 mm).

RESULTS

3 (1.5%) of 197 patients had an unknown thrombosis of the caval system (renal vein, ovarian vein, lilac veins). A fourth patient had an unknown thrombosis of the mesenteric vein. All these patients had a pulmonary embolism (4/40). None of the 157 patients without pulmonary embolism at helical CT showed deep venous thrombosis.

CONCLUSION

In our study, CT of the abdomen and pelvis disclosed an unknown thrombosis of a deep vein of the abdomen and pelvis that can explain the pulmonary embolism in 7.5% of patients.

Epithelioid hemangioendothelioma of the superior vena cava: computed tomography demonstration and review of the literature

A case is reported of a 79-year-old man with rapid onset of superior vena cava syndrome caused by an epithelioid hemangioendothelioma. Contrast-enhanced helical computed tomography showed a soft-tissue mass with punctate calcifications obstructing the superior vena cava and infiltrating adjacent fat. Epithelioid hemangioendothelioma is a very rare primary mesenchymal tumor of the superior vena cava that often presents with calcifications. It should to be added to the differential diagnosis of tumors of the anterior mediastinum.

Acute pulmonary embolism: role of helical CT in 164 patients with intermediate probability at ventilation-perfusion scintigraphy and normal results at duplex US of the legs

PURPOSE

To assess prospectively the clinical effectiveness of helical computed tomography (CT) in the evaluation of patients with unresolved suspicion for pulmonary embolism (PE).

MATERIALS AND METHODS

Helical CT was performed in 164 consecutive patients suspected of having acute PE, intermediate probability at ventilation-perfusion (V-P) scintigraphy, and normal findings at duplex ultrasonography (US) of the legs. Fifteen patients also underwent pulmonary angiography. Helical CT results were analyzed immediately to help plan anticoagulant treatment. If helical CT did not show PE, anticoagulant treatment was not indicated. Clinical outcome for these patients was assessed during 3-month follow-up.

RESULTS

In 40 (24.4%) of 164 patients, the diagnosis of PE was based on results at helical CT (n = 39) or pulmonary angiography (n = 1). Repeated Doppler US of the legs depicted one thrombus in the calf of three patients with normal results at helical CT that could have been responsible for PE. During 3-month follow-up, three patients experienced recurrent PE (one death, two recurrences). Therefore, PE occurred in six (5.4% [95% confidence interval, 1.3%, 9.7%]) of 112 patients with normal findings at helical CT who did not receive anticoagulant treatment.

CONCLUSION

Findings at helical CT allowed accurate diagnosis of acute PE in patients with intermediate probability at V-P scintigraphy and without deep venous thrombosis at duplex sonography of the legs.

Central airway stenoses: preliminary results of spiral-CT-generated virtual bronchoscopy simulations in 29 patients

The purpose of this study was to determine the feasibility of using virtual bronchoscopy simulations to depict stenoses of the tracheobronchial tree. Virtual bronchoscopy simulations, based on ray casting, were applied to spiral-CT data sets of 29 patients presenting 41 stenoses of the central airways, proved with fiberoptic bronchoscopy. Simulations of the inner walls of the airways were of good quality in 27 of 29 patients. Airway stenoses were depicted in 39 of 41 cases. Evaluation of the length of stenoses and surrounding tissues required simultaneous display of multiplanar reformations. Virtual bronchoscopy provides a valuable road map for bronchoscopy, in an image format familiar to bronchoscopists.

Localized benign fibrous tumors of the pleura: MR appearance

PURPOSE

Our goal is to describe the MR findings in benign localized fibrous tumors of the pleura.

METHOD

Chest radiographs, CT scans, and MR images of four patients with localized benign fibrous tumors of the pleura were retrospectively reviewed and correlated with the pathologic findings.

RESULTS

Tumors ranged from 4 to 18 cm in their largest diameter. Three tumors were located in the diaphragmatic region, and one was within the left major fissure. All tumors were round to ovoid, pedunculated, and well delineated. On T1-weighted SE MR images, tumors showed low signal intensity. All tumors had heterogeneous but predominantly low signal intensity on proton-density-weighted images and lower signal intensity on T2-weighted images.

CONCLUSION

Localized benign fibrous tumors of the pleura were characterized by low signal intensity on all MR sequences that is explained by high collagen content within the tumors' stroma and should suggest the diagnosis preoperatively.

Case report. Pulmonary involvement in Niemann-Pick disease subtype B: CT findings

We present a case of Niemann-Pick disease subtype B in which the excessive storage of sphingomyelin within lung interstitium and alveoli produced an infiltrative lung disease demonstrated on high-resolution CT (HRCT). HRCT findings were correlated to pathological features.

Case report. Aortic pseudoaneurysm with aortobronchial fistula: diagnosis with CT angiography

We report the case of an 82-year-old man with a 12-month history of recurrent hemoptysis caused by an aortobronchial fistula. Twenty-five years earlier, the patient underwent placement of an aortic graft for aortic transection sustained in a motor vehicle accident. Chest radiography and bronchoscopy showed nonspecific abnormalities. We emphasize the role of CT angiography with 2D and 3D reconstructions for the diagnosis of and surgical planning for this rare but potentially lethal aortic postoperative complication.

False aneurysm of the pulmonary artery induced by a Swan-Ganz catheter: clinical presentation and radiologic management

OBJECTIVE

This study evaluates retrospectively the clinical presentation, radiographic findings, and angiographic management of false aneurysm of the pulmonary artery resulting from Swan-Ganz catheter placement.

MATERIALS AND METHODS

Over a 4-year period, seven false aneurysms of the pulmonary artery were diagnosed in five patients (four women, one man) who were 67-81 years old. All five patients underwent Swan-Ganz catheter placement to monitor cardiac surgery--coronary artery bypass grafting in four and mitral valve replacement in one. All patients were anticoagulated. For five patients, we reviewed the medical records and the results of chest radiography, digital subtraction pulmonary angiography, and pulmonary artery embolization. For two patients, we reviewed the results of CT scanning.

RESULTS

Non-life-threatening hemoptysis was noted in all cases and occurred in three patients after the Swan-Ganz catheter had been removed (elapsed time of 1-19 days). Chest radiographs revealed a pulmonary infiltrate in one patient and a pulmonary mass in two patients. The results were unremarkable in the other two patients. CT depicted two false aneurysms of the pulmonary artery as round masses with eccentrically enhanced lumina circumscribed by thrombosis. Pulmonary angiography revealed a single false aneurysm in three patients and two false aneurysms in two patients. All false aneurysms were localized in segmental or subsegmental branches of the right middle pulmonary artery (n = 4) or the right lower pulmonary artery (n = 3). All patients were successfully treated with transcatheter steel-coil embolization.

CONCLUSION

Even when the chest radiograph appears unremarkable, patients clinically suspected of developing a false aneurysm of the pulmonary artery after Swan-Ganz catheter placement require enhanced CT or pulmonary angiography to establish the diagnosis. False aneurysms of the pulmonary artery can be treated at the time of pulmonary angiography by steel-coil embolization.

Tracheobronchial tree: three-dimensional spiral CT with bronchoscopic perspective

The purpose of this report is to describe an original 3D technique that permits bronchoscopic perspective simulations of the tracheobronchial tree on an affordable workstation. Software based on surface shading was developed to permit navigation through the central airways using spiral CT data. Multiplanar reformations are displayed simultaneously with the virtual bronchoscopy simulations to give information about tissues surrounding the airways. Two clinical examples are reported to illustrate the value of this advanced computer technique.