Lung scintigraphy and helical computed tomography for the diagnosis of pulmonary embolism: a meta-analysis

To assess the diagnostic value of lung scintigraphy and helical computed tomography (hCT) in patients with suspected pulmonary embolism (PE), all English-language articles that described lung scintigraphy and hCT in patients with suspected PE were retrieved. Articles were assessed for strength of methodology, based on nine a priori-defined criteria. Parameters of diagnostic accuracy and results of management studies were calculated and evaluated. Lung scintigraphy is diagnostic in approximately 50% of patients with suspected PE. A normal perfusion scan has a chance of recurrent PE in two of 693 patients (0.3%; 95% CI: 0.2-0.4%; fatal in 0.15%). A high-probability lung scan is correlated with angiographically proven PE in 308 of 350 patients (88%; 95% CI: 84-91%). Pulmonary embolism was proven in 385 of 1529 patients (25%; 95% CI: 24-28%) with a nondiagnostic lung scan. Helical CT studies were compared with angiography and lung scintigraphy in 1171 patients, with a prevalence of PE of 39%. The sensitivity and specificity of hCT was 283/320 (88%; 95% CI: 83-91%) and 374/408 (92%; 95% CI: 89-94%), respectively. Only one prospective management study using hCT was available. In patients in whom anticoagulants were withheld based on a normal hCT study, recurrent thromboembolic events occurred in six of 109 patients (5.5%; 95% CI: 2-12%), with one fatality (1%; 95% CI: 0.02-4.3%). Lung scintigraphy is evaluated extensively and yields a diagnostic result in 50% of patients. Helical CT has similar positive predictive value to a high-probability lung scan. However, the exact role of hCT in the management of patients with suspected PE needs to be determined in prospective studies.

[Second Opinion Consult Clinic for Surgical Oncology in the Daniel den Hoed Clinic: analysis of the first 245 patients]

OBJECTIVE

To determine the characteristics and outcome in patients visiting a surgical oncology outpatient clinic for a second opinion.

DESIGN

Prospective and descriptive.

METHOD

From October 1996 till December 1998, 245 patients visited the Second Opinion Outpatient Clinic of the department of Surgical Oncology of the University Hospital Rotterdam/Daniel den Hoed Cancer Centre, Rotterdam, the Netherlands. The oncological data were recorded. The patient's satisfaction with their first physician and the hospital was scored in a standardized way. Cytological, histological and radiological material was revised and discrepancies with the results from elsewhere were recorded. The results of comparing the first and second opinion were retrospectively categorized as: identical; not identical without consequences for the prognosis but with implications for the quality of life; not identical with implications for the prognosis.

RESULTS

The primary tumour was breast cancer in 58% of the patients, 19% had a tumour of the digestive tract, and 23% presented with a variety of malignancies. The main problems for which the second opinion was asked were treatment (69%), diagnosis (17%) and adjuvant treatment (11%). Of all patients 53% was satisfied with the communication with the primary physician, 24% was moderately satisfied and 23% was unsatisfied. Revision of pathological and radiological material was done in 214 and 157 patients, respectively, resulting in 1% and 3% major discrepancies with therapeutical implications. The second opinion was identical to the first opinion in 53% of the patients. In 24% it was different without and in 7% with possible implications for the prognosis. In 16% a comparison of the second with the first opinion was not possible. Seventy-one per cent of the patients were referred to the primary physician, while for 21% further treatment or follow-up was done in the Cancer Centre and 8% chose to be referred to another hospital. Of patients who were satisfied or moderately satisfied with the communication with their primary physician 83% and 79% respectively were referred to the primary physician compared with 31% of those who were unsatisfied.

In vivo assessment of three dimensional coronary anatomy using electron beam computed tomography after intravenous contrast administration

Intravenous coronary angiography with electron beam computed tomography (EBCT) allows for the non-invasive visualisation of coronary arteries. With dedicated computer hardware and software, three dimensional renderings of the coronary arteries can be constructed, starting from the individual transaxial tomograms. This article describes image acquisition, postprocessing techniques, and the results of clinical studies. EBCT coronary angiography is a promising coronary artery imaging technique. Currently it is a reasonably robust technique for the visualisation and assessment of the left main and left anterior descending coronary artery. The right and circumflex coronary arteries can be visualised less consistently. Improvements in image acquisition and postprocessing techniques are expected to improve visualisation and diagnostic accuracy of the technique.

Intravenous coronary angiography using electron beam computed tomography

Intravenous coronary angiography with electron beam computed tomography (EBCT) allows for the noninvasive visualisation of coronary arteries. With dedicated computer hardware and software, three-dimensional renderings of the coronary arteries, veins, and other cardiac structures can be constructed from the individual transaxial tomograms. Interest in this technique is growing, and recently a number of clinical studies have been published comparing EBCT coronary angiography with conventional cine-coronary angiography. In this article, image acquisition, postprocessing techniques, and the results of recently published clinical studies are discussed. EBCT coronary angiography is a promising imaging technique of coronary arteries. Currently, it is a reasonably robust technique for the visualization and assessment of the left main and left anterior descending coronary artery. However, at the moment a relatively high proportion of the right and circumflex coronary angiograms are noninterpretable. Improvements in image acquisition and postprocessing techniques are expected to improve visualization and diagnostic accuracy of the technique.

[Electron-beam computed tomography: preliminary experiences in the Netherlands]

The difference between computer tomography (CT) and electron beam tomography (EBT) is that for CT the x-ray tube rotates in a ring round the patient, and for EBT the x-ray beam rotates itself. As a result, with EBT the speed of making images is not limited by the mechanical rotation of the tube, and 16 images can be made per second. An EBT scan of a whole thorax takes 9 seconds. Specific application areas are fast moving organs and patients who cannot remain in one position for long, e.g. children and intensive care patients. Research is being conducted into the possibilities of this non-invasive technique for the demonstration of coronary artery lesions, pulmonary embolism, pulmonary metastases and dynamic examination of the major respiratory tract. Costs of an EBT scan currently amount to Dfl. 450.--but they will probably decrease as this imaging system is developed further. The exposure to radiation is about the same as that caused by a (spiral) CT.

Haematuria: intravenous urography, ultrasound or both?

PURPOSE

To compare the diagnostic value of intravenous urography (IVU), ultrasound (US) and their combination in detecting upper urinary tract malignancies in patients with haematuria.

MATERIALS AND METHODS

In a prospective study, 360 consecutive patients who consulted the urologist for haematuria without renal colic were scheduled for IVU and US on the same day. The two procedures were performed by two different radiologists and reported independently. Histology or clinical follow-up of one year served as the gold standard.

RESULTS

63 patients dropped out. Of the remaining 297 patients, 9 (3%) had a malignancy in the upper urinary tract. Sensitivity and specificity with regard to the upper urinary tract pathology were 67% and 91% for IVU and 56% and 94% for US, respectively. For both techniques combined this was 79% and 88%, respectively.

CONCLUSION

An acceptable sensitivity for detecting upper urinary tract malignancies is obtained only by combining IVU and US.

Erectile dysfunction: timing of spectral wave-form analysis in the assessment of the function of the cavernosal arteries

Color Doppler ultrasound seems to be an accurate method to evaluate vascular erectile function, in particular the arterial supply of the penis. Because of its relative noninvasiveness and easy performance, it has to precede more invasive evaluation (cavernosography and invasive angiography). Combination of wave form pattern analysis with peak systolic velocity measurements allows differentiation between arterial and venous insufficiency. Fifty-one patients suffering from erectile dysfunction, were examined with use of color Doppler ultrasound. Nine had adequate vascular function with good penile tumescence. However, during these adequate (late) stages of tumescence, peak systolic velocity fluctuated significantly. We conclude that in the late stages of tumescence, velocity measurements are not reliable as a parameter of arterial function.