Pictorial review of the many faces of bronchioloalveolar cell carcinoma.

Bronchioloalveolar cell carcinoma (BAC) has a varied appearance on CT that often leads to an incorrect or delayed diagnosis. The purpose of this pictorial review is to define common CT characteristics that are specific to BAC. A retrospective review was undertaken of 20 CT scans of pathologically proven cases of BAC; tumours were categorized as focal or diffuse, single or multiple, and infiltrative or well defined. Additional radiological features noted include the density (solid, part solid, non-solid), the presence of unaffected vessels within the tumour(s), and the presence of internal air bronchograms. We illustrate cases of localized and diffuse BAC presenting as (i) solitary or multiple pulmonary nodules, with and without air bronchograms, (ii) bubble-like lucencies of pseudocavitation associated with nodules of varying density, (iii) unifocal or multifocal ground-glass opacities, (iv) crazy paving, (v) nodules and airspace opacities with unaffected vessels coursing through them and (vi) lobar or multilobar consolidation and cavitating nodules. In conclusion, BAC may present with a variety of CT appearances. However, there are typical features such as the CT-angiogram sign or air-brochochograms in solitary nodules and in the periphery of larger consolidations, persisting pure ground-glass opacities, unresolving consolidation and the combination of diffuse nodules and consolidation. These features should alert the radiologist to the diagnosis of BAC.

Creation of a software application for the clinical radiologist.

PURPOSE: To create a software application that automates a significant portion of a clinical radiologist's work. METHODS: The daily workflow of clinical radiologists in a university-based department was analyzed, specifically looking for manual tasks that could be implemented in software. An application that a practicing radiologist would use in his daily work was created. RESULTS: By using speech recognition, reports could be created, edited, and verified immediately. Online medical reference information could be made instantly accessible. Billing data could be captured accurately and completely at report creation time. A radiologist could be alerted to important upcoming events by use of a reminder system. Reports could be delivered immediately to referring physicians using either the internet or telephone. CONCLUSIONS: It is possible to improve the productivity of busy practicing clinical radiologists by automating a large portion of their workflow and implementing it in an easily mastered software application.

Correlation of chest radiographic findings with biopsy-proven acute lung rejection.

The purpose of this study was to determine the chest radiographic findings of acute rejection and the accuracy of chest radiography in making this diagnosis in patients undergoing lung transplantation. For each of 100 transbronchial biopsies performed on 25 lung transplant recipients (single lung in three, double lung in 22), chest radiographs obtained within 24 hours before the biopsy were reviewed retrospectively without knowledge of clinical or biopsy information. Transbronchial biopsy revealed 42 instances of acute rejection in 17 patients and 58 instances of no acute rejection (normal, n = 43; other processes, n = 15). All pulmonary parenchymal radiographic abnormalities were assessed. Acute rejection was associated with the presence of middle or lower lung reticular interstitial or airspace disease in 21 lungs (sensitivity = 0.50 [21/42]). This pattern was seen in 18 lungs without acute rejection (specificity = 0.69 [40/58]). There was no difference in the appearance of the lungs between grades 1 and 2 acute rejection. Normal lungs were noted in 20 instances of acute rejection (48%). The authors conclude that chest radiograph findings are abnormal in about 50% of instances of biopsy-proven acute rejection. Because the appearance of acute rejection is similar to that of other conditions, the diagnosis cannot be made accurately by chest radiography.

Utility of electron microscopy in the assessment of transthoracic needle lung biopsy specimens.

RATIONALE AND OBJECTIVES: The authors determine the usefulness of electron microscopy (EM) in the workup of patients with certain intrathoracic masses undergoing transthoracic needle biopsy (TNB). METHODS: Over a 4-year period, 1603 patients underwent TNB at our institution. Of these, 79 had EM examination of the aspirated material. The study is a retrospective review of this latter group. Previous use of EM for TNB had suggested that it may he helpful in those with pleural, chest wall, and mediastinal lesions. The 40 men and 39 women had pulmonary (n = 49), mediastinal (n = 17), pleural (n = 10), and chest wall (n = 3) lesions. RESULTS: The adequate specimen rate was 59% (47 of 79) for light microscopy (LM) and 37% (29 of 79) for EM. Of the 28 patients with satisfactory specimens for both LM and EM, the correct diagnosis was obtained by LM 79% (22 of 28) and EM 96% (27 of 28) of the time. Electron microscopy was most helpful in patients with mediastinal (6 of 6 correct versus 3 of 6 for LM) and pleural (3 of 3 versus 1 of 3) lesions. CONCLUSIONS: In specific circumstances, EM can be a very useful adjunct to LM in patients undergoing TNB. Problems with sample adequacy must be addressed.

Reperfusion edema after lung transplantation: radiographic manifestations.

PURPOSE: To characterize the radiographic manifestations of reperfusion edema after lung transplantation and to correlate the severity of the radiographic findings with pulmonary physiology. MATERIALS AND METHODS: Chest radiographs obtained after 45 lung transplantation procedures (20 single, 25 double) were reviewed retrospectively. Physiologic parameters (alveolar-arterial gradient, ratio of partial pressure of oxygen to fraction of inspired oxygen) were noted in patients who underwent intubation. RESULTS: Reperfusion edema appeared on day 1 in 39 transplants and by day 3 in 44. One patient's lungs remained clear. Peak severity occurred by day 4 in 43 of 44 transplants. At peak severity, reperfusion edema appeared as reticular interstitial disease in the upper (19%), middle (33%), and lower (34%) lung zones or air-space disease in the upper (31%), middle (61%), and lower (57%) zones. Reperfusion edema was asymmetric after double-lung transplantation in nine patients. The process cleared by day 10 in five transplants and by day 21 in another seven. There was a poor correlation between the severity of radiographic findings and physiologic measurements. CONCLUSION: Reperfusion edema is almost invariable after lung transplantation and most often appears as air-space disease in the middle and/or lower lung zones. The severity of radiographic findings is a poor indicator of pulmonary physiology.

Accuracy of a voice-to-text personal dictation system in the generation of radiology reports.

OBJECTIVE: Systems that convert spoken words directly into text have recently become available. The purpose of this study was to test the accuracy, on a word-for-word basis, of one such system for generating radiology reports. MATERIALS AND METHODS: The IBM Personal Dictation System (IPDS), with the optional add-on radiology vocabulary, was assessed (the system is now known as VoiceType Dictation). The system requires one to use discrete speech (i.e., with a momentary pause between words). Two hundred current radiology reports, including 100 consecutive chest radiographs, 50 consecutive thoracic CT scans, and 50 random sonography and angiography reports, were read to the system. Before testing, the IPDS had been used in the dictation of material related to chest radiology. All errors were noted on a word-for-word basis and categorized as follows: incorrect, partially incorrect (no effect on meaning), not in dictionary (word was then added), homophone, or formatting. Medical words (those thought to be relevant to the meaning of the report) were considered separately. Specific assessments of numbers and dates were made. Words added to the dictionary were reread after the 200 reports had been assessed. RESULTS: When all mistakes were considered, the accuracy was 0.99 for chest radiology and 0.96 for material not concerning chest radiology. When only relevant mistakes on medical words were considered, the accuracies were 0.98 and 0.96, respectively. Accuracy for numbers was 0.95 and for dates 0.97. Redictation of the 22 words previously not in the dictionary was 100% accurate. CONCLUSION: The IPDS is an accurate system for direct voice-to-text dictation of radiology reports that improves with continued use. The most important future enhancement of such systems will be to allow the more natural continuous or conversational speech style.

Cystic change (pseudocavitation) associated with bronchioloalveolar carcinoma: a report of four patients.

Cavitation in bronchioloalveolar carcinoma is uncommon, but apparent radiologic cavitation may be produced by other causes of abnormal air collections in and around the tumor. We report four patients whose plain films and computed tomography scans were interpreted as showing cavitary masses. Paracicatricial emphysema, fibrosis with honeycombing, and localized bronchiectasis were present pathologically to explain the abnormal air collections.

Radiologic assessment after lung transplantation.

Imaging studies play a major role in patients undergoing lung transplantation. These patients are subject to unusual problems, such as the reimplantation response, acute rejection, bronchiolitis obliterans, ischemia-induced airway complications, and immuno-suppression-associated lymphoma. In addition, these patients are also subject to all of the usual problems associated with thoracic surgery, including atelectasis, infection, pneumothorax, and pleural effusion, all conditions for which radiologic assessment is crucial.

Congenital bronchopulmonary diseases in adults: CT findings.

Congenital lung disease is divided into two types: lesions that arise from the primitive foregut (i.e., bronchopulmonary malformations) and lesions that originate in the pulmonary vasculature. The latter often are detected early in life because of signs and symptoms or other serious associated anomalies. Conversely, many of the bronchopulmonary anomalies are asymptomatic and therefore are not discerned until adulthood. This essay illustrates the spectrum of CT findings of many congenital bronchopulmonary malformations that are seen in adults, including pulmonary agenesis, anomalous bronchial branching, bronchial atresia, foregut cysts, bronchopulmonary sequestration, and pulmonary arteriovenous malformations.

Pulmonary manifestations of coccidioidomycosis.

Pulmonary coccidioidomycosis is a fungal disease seen primarily in the southwestern United States and Mexico. However, with the advent of mass travel it is being seen increasingly in countries outside the zone where it is endemic. Pulmonary coccidioidomycosis, which has a high infectivity, is acquired by inhalation of fungal arthrospores. Its infectivity is increased in immunosuppressed patients, particularly those with the acquired immunodeficiency syndrome. Because of these factors, it is important for radiologists (particularly those practising outside the area of endemicity) to recognize the various manifestations of this disease. The authors review the major clinical syndromes and their radiologic manifestations.

Mediastinal invasion by bronchogenic carcinoma: CT signs.

PURPOSE: To determine the accuracy of computed tomographic (CT) signs in assessment of direct mediastinal invasion by primary bronchogenic carcinoma. MATERIALS AND METHODS: In 90 patients with primary bronchogenic carcinoma who underwent CT with thoracic surgical staging and thoracotomy, the pathologic and CT findings in 14 mediastinal structures were compared retrospectively. The degree of contact of the primary tumor with each structure and whether the structure was distorted or contained intraluminal tumor were recorded. A total of 785 mediastinal structures (25 with tumor invasion) were analyzed. RESULTS: When greater than 90 degrees of contact was considered a positive CT finding, the sensitivity of CT was 40% (10 of 25 structures); specificity, 99% (752 of 760 structures); and positive and negative predictive values, 56% and 98%. All structures with > 180 degrees of contact had pathologic involvement, but only 11 of 17 distorted structures (65%) and five of seven structures with intraluminal tumor (71%) were involved. CONCLUSION: CT is insensitive in detection of mediastinal invasion by primary bronchogenic carcinoma. The positive predictive value may be higher, depending on the criteria used.

Bronchioloalveolar carcinoma and the air bronchogram sign: a new pathologic explanation.

Bronchioloalveolar carcinoma (BAC) is one of the few lung tumors known to demonstrate the air bronchogram sign. Production of this valuable radiologic sign by this tumor has been ascribed to an "alveolar" filling process in which tumor grows along alveolar walls with preservation of the architecture and secretes copious amounts of mucus. Thus, aerated bronchi are surrounded by alveoli that are filled with mucus and tumor. We present a case in which the air bronchogram sign and pulmonary consolidation are associated with a nonsecretory BAC. Alternative mechanisms that may produce the air bronchogram sign in BAC are offered.

Staging of bronchogenic carcinoma.

Both computed tomography (CT) and magnetic resonance imaging (MRI) can provide important information not obtainable by chest radiography regarding staging of patients with bronchogenic carcinoma. However, while CT and MRI can both detect enlarged mediastinal nodes, this only approximately indicates tumor involvement. For example, enlarged nodes do not necessarily contain tumor, so biopsy is necessary before declaring the patient inoperable. As well, normal-sized nodes may contain tumor, and whether mediastinoscopy is required in such situations is controversial. Similarly, neither MRI nor CT is highly accurate in detecting mediastinal or chest-wall involvement, although certain specific features can occasionally be highly predictive of invasion.

Tangential fluoroscopic guidance of the anesthetizing needle during transthoracic needle lung biopsy: a randomized controlled clinical trial.

The effectiveness of tangential fluoroscopic guidance of the anesthetizing needle to avoid transgression of the pleura and therefore lower pneumothorax and chest tube insertion rates after transthoracic needle lung biopsy (TNB) was investigated. Tangential guidance was used in 41 patients (group A) and was not used in 51 (group B). The pneumothorax rate was 39% (16 of 41) for group A and 31% (16 of 51) for group B. The chest tube insertion rate was 12% (five of 41) for group A and 4% (two of 51) for group B. None of the differences in rates were significant. Use of this technique does not lower pneumothorax or chest tube insertion rates in patients undergoing TNB.

Precocious emphysema in intravenous drug abusers.

It is becoming increasingly clear that obstructive airway disease and early emphysema occur in some drug addicts who intravenously abuse drugs intended for oral use. We report four patients with such a history who had clinical, pathophysiologic, and radiologic evidence of severe obstructive airway disease with hyperinflation. Three patients had bullae. All had radiologic changes of intravenous talc granulomatosis. One patient had moderately severe emphysema at autopsy. The pathogenesis of this disease is uncertain but may involve synergism with cigarette smoke, direct toxic effects of the drug, or induced intravascular leukocyte sequestration causing proteolytic pulmonary injury.

Thin-walled cystic lesions in bronchioalveolar carcinoma.

In a retrospective study, thin-walled cystic lesions were identified in four patients with proved bronchioalveolar carcinoma (BAC). The radiographic appearances are described, and possible mechanisms of formation of the lesions are discussed. Although such appearances due to BAC have rarely been described in the literature, the authors believe that the differential diagnosis of thin-walled cystic lesions associated with consolidation should include BAC.

Intracranial meningioma with pulmonary metastases: diagnosis by percutaneous fine-needle aspiration biopsy and electron microscopy.

The authors report a patient with a history of recurrent intracranial meningiomas in whom two lung nodules developed. A percutaneous fine-needle aspiration biopsy of one nodule demonstrated spindle-form cells; the tumour was specifically diagnosed as metastatic meningioma on the basis of electron microscopic findings.

Anterior mediastinal masses: utility of transthoracic needle biopsy.

The results of 143 transthoracic needle biopsies (TNBs) in 126 patients with anterior mediastinal masses were compared with the final diagnosis, which was proved with pathologic study (n = 95) or clinicoradiologic methods (n = 31). In the 26 patients with lymphoma, the sensitivity of TNB was 42%; the specificity, 96%. In the 15 patients with Hodgkin disease, the sensitivity was 20%. In the 28 patients with thymoma, the sensitivity was 71%; the specificity, 94%. In the 11 patients with germ cell tumors, the sensitivity was 91%; specificity, 98%. The sensitivity in the 33 patients with metastatic disease was 70%; specificity, 100%. The cytologic specimens were examined with light microscopy and the Papanicolaou method only, a limitation that explains the difficulty in differentiating lymphoma from thymoma and that can now be overcome with immunohistochemical study. TNB of anterior mediastinal masses is useful in metastatic disease and germ cell tumors. Lymphoma and thymoma are less reliably diagnosed unless immunohistochemical cytologic methods are applied.

Bronchiolitis obliterans after lung transplantation: findings at chest radiography and high-resolution CT. The Toronto Lung Transplant Group.

Although bronchiolitis obliterans (BO) is seen commonly after heart-lung transplantation, its occurrence after lung transplantation appears to be relatively infrequent. In the 55 single- and double-lung transplantations performed at Toronto General Hospital, 41 patients have survived longer than 3 months and four (10%) have developed pathologically proved BO. Chest radiographic findings in these four patients included slight to moderate decreased peripheral vascular markings (n = 3), slight to moderate volume loss (n = 2), subsegmental atelectasis (n = 2), and new, thin, linear, irregular areas of increased opacity (n = 2). High-resolution computed tomography (HRCT) demonstrated mild peripheral bronchiectasis (n = 4) and decreased peripheral vascular markings (n = 3). Although the radiographic and HRCT findings did not appear to be specific for posttransplantation BO, they may be of value in suggesting the diagnosis of BO within this patient population.