Diagnosis of pulmonary embolism: ventilation perfusion scintigraphy versus helical computed tomography pulmonary angiography.

The present study compared the accuracy of ventilation perfusion scintigraphy (VQS) and CT pulmonary angiography (CTPA) for the diagnosis of pulmonary embolism. This was a prospective observational study of 112 patients with suspected pulmonary embolism (PE) who could be studied with both investigations within 24 h. Results were compared to final diagnosis at completion of 6-month follow up, using receiver operating characteristic (ROC) analysis. Pulmonary embolism was diagnosed in 27 referred patients (24%). The sensitivity and specificity of VQS and CTPA were similar to that reported from the literature. A normal VQ scan had the highest negative predictive value (100%), while a high-probability VQ scan had the highest positive predictive value (92%). There was no overall difference (area under the ROC curve (AUC)) between VQS (AUC (95% CI) = 0.82 (0.75,0.89)) and CTPA (AUC = 0.88 (0.81,0.94)) for the diagnosis of PE. Among patients with abnormal chest X-rays, CTPA (AUC 0.90 (0.83,0.97)) appeared somewhat better than VQS (AUC 0.78 (0.68,0.88)) but this difference did not reach statistical significance. In this instance, CTPA is at least as accurate as VQS and may provide an opportunity to make alternative diagnoses.

High prevalence of osteoporosis in cardiac transplant recipients and discordance between biochemical turnover markers and bone histomorphometry.

OBJECTIVE: All patients attending the cardiac transplantation clinic at the Royal Perth Hospital were investigated to determine the prevalence of osteoporosis and to assess changes in bone metabolism and histomorphometry in a cohort of cardiac transplant recipients. DESIGN: Retrospective cross-sectional study. PATIENTS: Thirty-two patients (27 male; 5 female) who had received a cardiac transplant during the past 10 years and who were receiving immunosuppressive therapy with cyclosporin, azathioprine and prednisolone were studied. MEASUREMENTS: All patients had bone densitometry by DEXA of the lumbar spine and femoral neck and X-rays of the thoracolumbar spine. Fasting serum ionized calcium, intact PTH, creatinine, 25 hydroxy-vitamin D, alkaline phosphatase, osteocalcin, testosterone and free thyroxine and urine calcium, creatinine, hydroxyproline and deoxypyridinoline were measured. Six osteoporotic patients consented to transiliac bone biopsy following double tetracycline labelling. RESULTS: Osteoporosis was present at the lumbar spine in eight patients, femoral neck in seven patients and was present at one or more sites in 13 patients (41%). Seven patients (22%) had vertebral fractures which were asymptomatic in five patients. Secondary hyperparathyroidism was present in 16 patients (53%) but significant renal failure (creatinine clearance < 70 ml/min) was only found in 8 (50%). Levels of biochemical markers of bone turnover were increased in 23 patients (72%). Serum osteocalcin (P = 0.02) and alkaline phosphatase (P = 0.04) were significantly higher in osteoporotic patients than in nonosteoporotic patients. Histomorphometric findings varied markedly between patients. Microscopic features of hyperparathyroidism were not observed. CONCLUSIONS: Osteoporosis and asymptomatic vertebral fractures are common following cardiac transplantation. Biochemical markers of bone turnover were increased in the majority of patients. Many had biochemical evidence of secondary hyperparathyroidism but this could be attributable to significant renal failure in only 50% of cases. Osteocalcin and alkaline phosphatase correlated inversely with bone density. Histomorphometric findings did not correlate with these biochemical changes in most cases. These results suggest that multiple factors are responsible for osteoporosis in cardiac transplant recipients. Osteocalcin and alkaline phosphatase may be useful biochemical markers, predicting patients at highest risk of fracture.

Extrinsic radiocarpal ligaments: magnetic resonance imaging of normal wrists and scapholunate dissociation.

OBJECTIVE: To determine whether magnetic resonance imaging [MRI] in planes of imaging parallel to the known course of the extrinsic radiocarpal ligaments of the wrist aids in the visualization of these structures. SUBJECTS AND METHODS: MRI was performed on 32 wrists: a single normal cadaveric wrist, 23 normal wrists in volunteers and 8 wrists in patients with known scapholunate dissociation and rotatory scaphoid subluxation. Proton-density and T2-weighted images were obtained in the sagittal plane and gradient recalled echo images in an oblique sagittal plane, selected to parallel the extrinsic radiocarpal ligaments. The images were interpreted by two musculoskeletal radiologists. Each of the six main extrinsic ligaments was assessed for visualization or nonvisualization, and the morphologic features of those visualized were documented. RESULTS: With the exception of the dorsal radioscaphoid ligament, the volar and dorsal extrinsic radiocarpal ligaments were all consistently visualized in the normal wrists. For the eight cases of scapholunate dissociation, MRI demonstrated underlying rupture or thickening of the volar radioscaphocapitate ligament in all wrists and of the dorsal radiolunate ligament in five. CONCLUSION: MRI in the true and oblique sagittal planes can consistently demonstrate the extrinsic radiocarpal ligaments of the wrist. With this technique, extrinsic ligamentous abnormality can be demonstrated in patients with scapholunate dissociation and rotatory scaphoid subluxation.

Arthrography of the contralateral, asymptomatic wrist in patients with unilateral wrist pain.

To determine the significance of arthrographic abnormalities in patients with unilateral wrist pain, the authors compared the prevalence and site of intra-articular ligament perforation in asymptomatic and symptomatic wrists of the same group of patients and correlated asymptomatic perforation with age, hand dominance and hand overuse. Thirty-seven patients (29 men and 8 women ranging in age from 19 to 61 years) who had unilateral wrist pain and positive arthrographic findings for the symptomatic wrist underwent radiocarpal arthrography of the asymptomatic wrist. Three radiologists blinded as to the clinical findings examined the images for perforation in the triangular fibrocartilage complex, the lunotriquetral ligament and the scapholunate ligament. Intra-articular ligament perforations were found in 33 (89%) of the 37 asymptomatic wrists. Seventeen (46%) of the 37 patients had symmetric sites of perforation in the two wrists. Perforation of the triangular fibrocartilage complex occurred in 22 (59%) and 19 (51%) of the symptomatic and asymptomatic wrists respectively, of the lunotriquetral ligament in 13 (35%) and 7 (19%) respectively and of the scapholunate ligament in 13 (35%) and 11 (30%) respectively. No significant correlation between asymptomatic perforation and age or hand overuse was found (chi 2 test, Fisher's exact test). The authors conclude that asymptomatic perforation is common, even in young patients, so ligament perforation is not necessarily the cause of wrist pain in patients with such pain. However, for patients with the appropriate clinical findings, arthrography can be used to confirm or exclude ligament perforation.

Diagnosis of diseases of the trachea and main bronchi: chest radiography vs CT.

OBJECTIVE: The purpose of this study was to compare the sensitivities and diagnostic accuracies of chest radiography and CT in the assessment of diseases of the trachea and main bronchi in regard to detection, evaluation of focal vs diffuse disease, separation of benign from malignant disease, and accuracy of diagnosis. MATERIALS AND METHODS: The chest radiographs and CT scans of 35 patients with proved diseases of the trachea and main bronchi and five control subjects were randomly assessed by two independent observers in a blind study. The diagnoses included 25 malignant and 10 benign conditions. The malignant lesions included 24 primary tumors and one metastatic melanoma. The benign lesions included two benign tumors, two tracheal stenoses, one focal amyloidosis, one tracheomalacia, and four miscellaneous diffuse abnormalities. The observers were asked to determine if an abnormality was present, to classify it as focal or diffuse and as benign or malignant, and to list the three most likely diagnoses. Sensitivities were compared by using the McNemar test. RESULTS: The sensitivity of both observers in detecting disease on the chest radiograph was 66%. The sensitivity on the CT scan was 97% for the first observer and 91% for the second observer (p < .01). Both observers were able to correctly classify the detected abnormalities as either focal or diffuse in 91% of cases on the chest radiographs and 97% of cases on the CT scans. The abnormalities were correctly classified as either benign or malignant in 78% of cases by both observers on the chest radiographs and in 85% and 78% of cases on the CT scans by the first observer and the second observer, respectively. The correct diagnosis was included in the list of the three most likely diagnoses in 61% of cases by both observers after reviewing the radiographs and in 56% of cases by one observer and 63% of cases by the other observer after reviewing the CT scans. CONCLUSION: CT is superior to chest radiography in allowing detection of abnormalities of the major airways. Both CT and chest radiography are accurate for differentiating focal from diffuse disease, but neither technique is accurate for distinguishing benign from malignant disease or for establishing a specific diagnosis.

Bronchiolitis obliterans: high resolution CT findings and correlation with pulmonary function tests.

In order to characterize the appearances of bronchiolitis obliterans on high-resolution CT (HRCT) and to relate the extent of HRCT abnormalities to pulmonary function tests, the HRCT scans of 18 patients with bronchiolitis obliterans were examined by two independent observers. The underlying causes for the development of bronchiolitis obliterans were penicillamine therapy (n = 5), previous infection (n = 4), graft-vs-host disease (n = 3), and miscellaneous causes (n = 6). Abnormal HRCT findings were present in all cases. The commonest HRCT abnormalities consisted of patchy areas of decreased parenchymal attenuation (n = 15), subsegmental (n = 12) and segmental (n = 6) bronchial dilatation and centrilobular branching structures (n = 5). There was no significant correlation between the extent of abnormalities and the static lung volumes or the impairment in gas transfer (all P values > 0.05). The only significant correlation was between the number of segments with subsegmental bronchial dilatation and the forced expiratory volume in one second (Wilcoxon r = 0.61, P < 0.01). We conclude that the great majority of patients with bronchiolitis obliterans have HRCT abnormalities. However, there is poor correlation between the extent of abnormalities on HRCT and functional impairment.

Tuberculosis of the chest wall: CT findings.

To assess the CT features of tuberculosis of the chest wall, the CT findings in four patients with documented tuberculous chest wall infection were reviewed. Two patients were Caucasian and two were of Chinese origin. All had normal immune status. In two cases tuberculosis involved the ribs, in one the costal cartilage, and in one the sternoclavicular joint. Computed tomography demonstrated osseous and cartilaginous destruction (in four), soft tissue masses with calcification (in two), and rim enhancement following intravenous contrast medium administration (in two). Underlying pleuroparenchymal tuberculosis was present in two cases. Tuberculosis of the chest wall is characterized by bone or costal cartilage destruction and soft tissue masses that may demonstrate calcification or rim enhancement with or without evidence of underlying lung or pleural disease.

Acute pulmonary complications in immunocompromised non-AIDS patients: comparison of diagnostic accuracy of CT and chest radiography.

To compare the abilities of computed tomography (CT) and radiography in detection and diagnosis of acute pulmonary complications in immunocompromised non-AIDS patients, the CT scans and radiographs of 45 immunocompromised non-AIDS patients with proven pulmonary disease and 20 normal controls were independently assessed by two observers, without knowledge of clinical or pathologic data. The observers listed the three most likely diagnoses and their degree of confidence in the first-choice diagnosis on a three-point scale. The sensitivity and specificity in detecting pulmonary complications was 100% and 98% for CT, compared to 98% and 93%, respectively, for chest radiography. In the immunocompromised patients, the first-choice diagnosis was correct in 44% of CT and 30% of radiograph readings (P < 0.01). The correct diagnosis was among the top three diagnoses in 70% of CT scans and 53% of radiograph readings (P < 0.01). Confidence level one (definite) was reached in 33% of CT scans and 10% of chest radiographs (P < 0.001). Diseases with a dominant nodular pattern had a higher occurrence of correct first-choice diagnosis (62% vs 34%, P < 0.02) and level one confidence ratings (53% vs 13%, P < 0.001) than diseases with ground-glass opacity, consolidation or irregular linear opacities. We conclude that chest radiographs and CT scans have comparable sensitivity in detecting acute pulmonary complications in immunocompromised non-AIDS patients. CT is superior to chest radiography in the differential diagnosis of acute pulmonary complications in these patients.

Pulmonary talcosis: CT findings in three cases.

The authors describe the computed tomographic (CT) appearances in three patients with pulmonary talcosis resulting from chronic intravenous drug abuse. There was widespread ground-glass attenuation in one case and an appearance similar to that of progressive massive fibrosis in two cases. In the latter cases, there were confluent perihilar masses with areas of high attenuation. While the CT appearances may be suggestive of pulmonary talcosis, tissue sampling is required for definitive diagnosis.

Diagnostic success of bronchoscopic biopsy in immunocompromised patients with acute pulmonary disease: predictive value of disease distribution as shown on CT.

OBJECTIVE: The purpose of the study was to determine if the distribution of pulmonary opacities on CT scans could be used to predict the outcome of bronchoscopic biopsy procedures in immunocompromised non-AIDS patients with acute pulmonary complications. MATERIALS AND METHODS: Thirty-three consecutive immunocompromised patients without AIDS who had acute pulmonary complications and who had had CT, bronchoscopic biopsy procedures, and proved diagnoses were included in the study. The distribution and dominant pattern of pulmonary opacities on CT were assessed independently by two observers. The pathologic diagnoses were invasive aspergillosis (eight), Candida pneumonia (six), bronchiolitis obliterans with or without organizing pneumonia (six), drug-induced lung disease (four), Pneumocystis carinii pneumonia (four), cytomegalovirus pneumonia (three), pulmonary hemorrhage (one), and recurrent lymphoma (one). RESULTS: The results of bronchoscopic techniques established a specific diagnosis in 17 patients (52%). In the remaining 16 patients, results of bronchoscopic biopsy could not be used to establish a specific diagnosis; open lung biopsy (15 patients) or transthoracic needle biopsy (one patient) were required for diagnosis. The results of bronchoscopic procedures were diagnostic more often in patients in whom pulmonary opacities involved the central third of the lung than in patients in whom the central third was spared (70% vs 23%, p = .02). Results were diagnostic more often in cases in which the causes of acute pulmonary complications were infectious than in cases in which the causes were noninfectious (71% vs 17%, p < .005). CONCLUSION: We conclude that the presence or absence of central disease as shown by CT can be used to suggest whether results of bronchoscopic procedures in immunocompromised non-AIDS patients will be diagnostic.

Chronic hypersensitivity pneumonitis: high-resolution CT and radiographic features in 16 patients.

To evaluate the manifestations of chronic hypersensitivity pneumonitis at radiography and high-resolution computed tomography (HRCT), findings in 16 patients with this disease were reviewed. To ensure objectivity, 50 patients with other chronic infiltrative lung diseases (fibrosing alveolitis [n = 29], sarcoidosis [n = 16], and miscellaneous conditions [n = 5]) were included. All patients had chronic disease with evidence of fibrosis at HRCT, as indicated by irregular linear areas and architectural distortion. Radiographs and HRCT scans were reviewed separately, in random order, and without knowledge of diagnosis. On radiographs and HRCT scans, the fibrosis in cases of hypersensitivity pneumonitis was situated predominantly in the middle lung zones or showed no zonal predominance. Lung apices and bases were relatively spared in all cases. The distribution of fibrosis in the transverse plane was random in seven cases, subpleural in six, and peri-bronchovascular in three. The distribution of fibrosis can allow distinction of chronic hypersensitivity pneumonitis from other causes of fibrosis in many cases.

Malignant mesothelioma of the tunica vaginalis testis.

A patient is described with an indolent scrotal mass complicated by acute hydrocoele which was proven to be due to malignant mesothelioma of the tunica vaginalis testis. Although uncommon, the possibility of scrotal mass lesion should be considered in ultrasound examination of hydrocoeles with atypical presentations.

Diverticular mass mimicking ovarian malignancy.

A patient is described with a large diverticular mass presenting with a clinical picture suggestive of locally advanced ovarian malignancy. Computed tomography demonstrated diffuse thickening of the wall of the sigmoid colon with infiltration of the peri-colonic fat. The imaging diagnosis of primary bowel wall disease was confirmed pathologically.