Bronchioloalveolar carcinoma: computed tomography findings

The aim of the present study was to investigate the appearance of bronchioloalveolar lung carcinoma on computed tomography (CT) scans, and to determine the frequency of signs suggestive of this diagnosis. CT features of 42 cases with pathologically proven bronchioloalveolar carcinoma were retrospectively analysed for pattern, size, location and secondary signs suggesting the diagnosis. Bronchioloalveolar carcinoma had one of the following patterns: solitary nodule or mass (16), lobar consolidation (10), multilobar consolidations (13) and diffuse nodules (3). The 16 solitary nodules or masses ranged in size from 2.0 to 9.4 cm (mean +/- SD 3.75 +/- 1.7 cm). Eleven of the 16 nodules or masses were peripheral and five were central: Eight of the 16 tumours had pleural tags, seven had spiculated margins, and three had bubblelike lucencies. The consolidations were peripherally distributed in 13 out of 23 cases; cystic airspaces were observed in 19 out of 23 consolidations; bulging of interlobar fissures in 8 out of 23; and the angiogram sign in 7 out of 23. In conclusion, computed tomography findings of bronchioloalveolar carcinoma have a wide spectrum, showing typically a peripheral nodule or consolidation. Computed tomography has a role in the diagnosis of nodular localized versus other forms, with subsequent therapeutic and prognostic implications.

Comparison of computed density and macroscopic morphometry in pulmonary emphysema

High-resolution computed tomography (HRCT) scans were obtained at 1 cm intervals in 63 subjects referred for surgical resection of a cancer or for transplantation to find out whether the relative area of lung occupied by attenuation values lower than a threshold would be a measurement of macroscopic emphysema. Using a semiautomatic procedure, the relative areas occupied by attenuation values lower than eight thresholds ranging from -900 to -970 HU were calculated on the set of scans obtained through the lobe or the lung to be resected. The extent of emphysema was quantified by a computer-assisted method on horizontal paper-mounted lung sections obtained every 1 to 2 cm. The only level for which no statistically significant difference was found between the HRCT and the morphometric data was -950 HU. To determine the number of scans sufficient for an accurate quantification, we recalculated the relative area occupied by attenuation values lower than -950 HU on progressively fewer numbers of scans and investigated the departure from the results obtained with 1 cm intervals. Because of wide variations in this departure from patient to patient, a standard cannot be recommended as the optimal distance between scans.

CT-guided percutaneous drainage of an anterior mediastinal abscess with a 16 F catheter

We report a case of anterior mediastinal abscess treated by percutaneous drainage under computed tomography (CT) guidance. The relationships of the abscess to the adjacent organs were clearly delineated by an intravenous injection of contrast material, and the drain was inserted between the sternum and the vasa thoracica interna. Selection of this route and the choice of a large-bore catheter (16 F) are discussed.

Can computed tomography quantify pulmonary emphysema?

In the last decade, several studies have suggested the possible role of computed tomography (CT) in the detection and the quantification of pulmonary emphysema. In order to verify whether this new method is adequately validated, this article gives an overview of these studies. The review shows that most of the studies used conventional CT and were based on visual scoring. Only a few were based on high resolution CT (HRCT) or concerned objective measurements of computed density. In addition, only a few studies included normal subjects and distinguished centrilobular from panlobular emphysema. The number of scans obtained in each study is extremely variable, whilst the minimum number necessary to provide accurate results remains unknown. Recently, automatic objective procedures which are truly quantitative and are applicable to HRCT have been made available. They should take the place of subjective scoring methods but further studies, based on macroscopic as well as on microscopic comparisons, are needed to validate and to standardize these techniques.

Can computed tomography quantify pulmonary emphysema?

In the last decade, several studies have suggested the possible role of computed tomography (CT) in the detection and the quantification of pulmonary emphysema. In order to verify whether this new method is adequately validated, this article gives an overview of these studies. The review shows that most of the studies used conventional CT and were based on visual scoring. Only a few were based on high resolution CT (HRCT) or concerned objective measurements of computed density. In addition, only a few studies included normal subjects and distinguished centrilobular from panlobular emphysema. The number of scans obtained in each study is extremely variable, whilst the minimum number necessary to provide accurate results remains unknown. Recently, automatic objective procedures which are truly quantitative and are applicable to HRCT have been made available. They should take the place of subjective scoring methods but further studies, based on macroscopic as well as on microscopic comparisons, are needed to validate and to standardize these techniques.

CT-guided percutaneous drainage of an anterior mediastinal abscess with a 16 F catheter

We report a case of anterior mediastinal abscess treated by percutaneous drainage under computed tomography (CT) guidance. The relationships of the abscess to the adjacent organs were clearly delineated by an intravenous injection of contrast material, and the drain was inserted between the sternum and the vasa thoracica interna. Selection of this route and the choice of a large-bore catheter (16 F) are discussed.

Macroscopic assessment of pulmonary emphysema by image analysis

AIMS

To propose a computerised image analysis based method for measuring, on paper mounted lung sections, the area macroscopically occupied by emphysema.

METHODS

The study was based on the assessment of 69 lung sections prepared following a modified Gough-Wentworth technique. The results obtained from image analysis, point counting, and panel grading methods were compared, as was the repeatability of image analysis and panel grading.

RESULTS

The results from image analysis and from point counting were not significantly different (p = 0.609) and significant quadratic regressions (r = 0.96, p < 0.001) were found between measurements from image analysis and from panel grading, the computerised technique being shown to be the most reproducible.

CONCLUSIONS

Image analysis is a valuable and reproducible method to measure the area of lung macroscopically involved by emphysema.

[Clinical role of spiral tomodensitometry in pulmonary disorders]

Spiral CT of the lungs has taken the place of conventional CT in most indications. Until now, some specific indications, concerning the detection of lung nodules, the detection of central pulmonary thromboembolism and the description of the angioarchitecture of pulmonary arteriovenous malformations have been reported. This paper provides an overview of the clinical utility of this new technique.

Persistent hyperinflation after heart-lung transplantation for cystic fibrosis

We have measured static lung volumes after heart-lung transplantation (HLT) in seven patients with cystic fibrosis (CF) (Group 1), three patients with chronic hyperinflation due to diseases other than CF (Group 2), and six patients with primary pulmonary hypertension (PPH) (Group 3). Total lung capacity was within normal limits at 1 yr after surgery in all patients. Similarly, FRC was within the normal range in Groups 2 and 3. On the other hand, patients with CF showed a persistent increase in FRC; at 1 yr after HLT, FRC averaged 4.13 +/- 0.52 L compared with a predicted value of 3.20 +/- 0.23 L (p < 0.01). The postoperative static pressure-volume curve of the lung in the patients with CF was superimposed on the predicted one, suggesting that the increased FRC originated in the chest wall. Additional studies with computerized tomographic scans demonstrated that the rib cage anteroposterior diameter at FRC averaged 12.1 +/- 1.6 cm in patients with CF, 9.5 +/- 1.2 cm in patients with PPH, and 9.4 +/- 0.7 cm in a group of healthy subjects matched with the patients with CF (p < 0.01). We conclude that after HLT, patients with CF show persistent hyperinflation due to rib cage expansion along the anteroposterior dimension. This shape change may represent a structural adaptation that occurs in response to chronic pulmonary hyperinflation acquired during rib cage growth.

Low grade coal worker's pneumoconiosis. Comparison of CT and chest radiography

We compared CT with chest radiography (CR) in the assessment of low grade coal worker's pneumoconiosis (CWP) in a population of 83 subjects. All subjects had a high-voltage p.a. CR, graded according to the ILO classification between 0/0 and 1/1, a conventional CT (CCT) using contiguous 1-cm-thick sections on the entire thorax and a set of 10 high-resolution CT (HRCT) images. CR and CT were separately read by consensus by 2 teams of 2 trained readers. CR was coded 0/0 in 9 subjects; 0/1 in 31; 1/0 in 28; 1/1 in 15. Among these groups of patients, micronodules were detected by CT in respectively 2 (22%), 14 (45%), 17 (61%) and 10 (67%) patients. In all groups, micronodules were more often detected by CT when the opacities detected on CR were scored as rounded (p, q) than irregular (s, t). Among the patients graded 0/0 or 0/1, CT showed micronodules in 40%. By contrast, among the patients graded 1/0 or 1/1, CT did not show micronodules in 37%, but revealed in numerous patients that opacities detected on CR were related to bronchiectasis and/or emphysema only. Comparative analysis of HRCT and CCT showed that both techniques are complementary and proved the usefulness of CCT in the detection or confirmation of low profusion of micronodules.

Conventional and high-resolution CT in asymptomatic asbestos-exposed workers

To compare the value of conventional CT (CCT) and high-resolution CT (HRCT) to detect benign asbestos-related diseases, 159 exposed workers with a normal chest radiography were imaged by both techniques. Pleural plaques were detected in a total of 59 cases (37.1%). Ten cases (16.9%) were detected by CCT only and one case (1.7%) by HRCT only. Pulmonary lesions compatible with parenchymal asbestosis were detected by HRCT in 20 cases, whereas CCT showed abnormalities in 45% of these. Rounded atelectasis was equally recognized by both techniques. The results confirm that in a subject with a normal chest radiography, HRCT is a better diagnostic tool to demonstrate lesions of asbestosis. On the other hand, HRCT is insufficient to exclude the presence of pleural plaques. When HRCT does not reveal pleural abnormalities, CCT should be performed.

Intramural esophageal cyst: the role of endoscopic ultrasonography

We report a case of symptomatic congenital esophageal cyst. The diagnostic approach and the role of endoscopic ultrasonography in the preoperative diagnosis, especially when computed tomography demonstrates a high attenuation mass, are emphasized.

Pneumonitis complicating low-dose methotrexate therapy for rheumatoid arthritis. Discrepancies between lung biopsy and bronchoalveolar lavage findings

Two very similar cases of drug-induced pneumonitis complicating treatment of rheumatoid arthritis with low-dose methotrexate are presented. Diagnosis was suggested by clinical history and findings, but the bronchoalveolar lavage showed a high percentage of neutrophils, an unusual feature in methotrexate-induced pneumonitis. Transbronchial lung biopsies (TBB) confirmed the diagnosis by showing interstitial lymphocytic infiltrate with microgranulomas. Although histologic findings are not strictly pathognomonic, when a differential diagnosis has to be made with infectious and rheumatoid lung disease, TBB appears to be of great promise.

Lung volume restriction in patients with chronic respiratory muscle weakness: the role of microatelectasis

BACKGROUND

It is well established that patients with longstanding weakness of the respiratory muscles have a reduction in lung distensibility. Although this occurs in most patients without any radiographic changes suggesting parenchymal lung disease, it has been attributed to the development of microatelectasis.

METHODS

A high resolution computed tomographic (CT) scanner was used in eight patients with traumatic tetraplegia and six patients with generalised neuromuscular disorders to look for areas of atelectasis. With the patient in the supine posture scans of 1 mm thickness were obtained at total lung capacity at intervals of 1 cm from the apex to the base of the lung.

RESULTS

Vital capacity, total lung capacity, and inspiratory muscle strength were reduced to a mean of 59.5%, 73.9%, and 51.1% of predicted values, respectively. Static expiratory lung compliance was decreased in 12 of the 14 patients and averaged 69.1% of the predicted value. The CT scans revealed only small areas of atelectasis in one tetraplegic patient and in one patient with a generalised neuromuscular disorder; no parenchymal abnormality was seen in the other 12 patients.

CONCLUSIONS

In many patients with chronic weakness of the respiratory muscles the reduced lung distensibility does not appear to be caused by microatelectasis. It might be related to alterations in elasticity of the lung tissue.

Dextroposition of the left lower lobe after heart-lung transplantation

Immediately after heart-lung transplantation for cystic fibrosis, a patient had development of a right lower lobe retrocardiac density that persisted on all postoperative chest radiographs. A computed tomographic examination of the thorax performed 3 weeks after surgery showed that there was partial collapse of the left lower lobe in the right hemithorax. The patient required a posterolateral thoracotomy for cure.

Fracture of the posterior aspect of the lateral tibial plateau: radiographic sign of anterior cruciate ligament tear

Plain radiographs obtained in 25 patients with acute anterior cruciate ligament (ACL) tears detected with magnetic resonance imaging were retrospectively evaluated to identify associated bone lesions. Fracture of the posterior part of the lateral tibial plateau (LTP) was seen in 11 patients, impacted fracture of the lateral femoral condyle (LFC) in two, lateral tibial rim fracture (Segond fracture) in three, and avulsion fracture of the tibial attachment of the ACL in two. The latter three fractures have been associated with an ACL tear. Conversely, fractures of the posterior part of the LTP have not been associated with ACL tear and are recognizable on plain radiographs. Impaction of the LFC on the LTP and avulsion of the posterior tibial capsular junction may account for the association of the fracture of the LTP with the acute ACL tear. This type of fracture represents the most frequent indirect sign of ACL tear seen on plain radiographs.