[The long-term results after Hydrolyser-supported angioplasty--a prospective study]. / Langzeit-Ergebnisse nach Hydrolyser-unterstützter Angioplastie--eine prospektive studie.

PURPOSE: Data of a three-year follow-up after mechanical thrombolysis with the Hydrolyser catheter were evaluated. Patients have otherwise been treated by local thrombolysis. METHOD: 35 patients were treated by thrombolysis, balloon angioplasty, aspiration, local thrombolysis, and stent placement, if necessary. Morphological results following Hydrolyser treatment and additional treatment were evaluated. RESULTS: Following Hydrolyser treatment a significant reduction of the degree and length of the occlusion was observed. Primary clinical success was 80%. Patency rate after 3 years was 0.5. 23% of all patients died in the follow-up period. CONCLUSION: The Hydrolyser treatment is a relevant alternative to local thrombolysis. This method reduces the time of treatment. The authors favor the lateral opening of the catheter to remove mural thrombus.

[Contrast medium clearance as a measure of kidney function in patients with renal artery stenoses]. / Kontrastmittel-Clearance als Mass der Nierenfunktion bei Patienten mit Nierenarterienstenosen (NAST).

The quantitative estimation of the characteristic radiation from 127I following external stimulation by 241americium photons makes it possible to estimate iodine concentration. The plasma concentration of non-ionic contrast media handled by glomerular filtration was measured in 16 patients with renal artery stenosis. This was done during diagnostic angiography or percutaneous dilatation, either at an early stage (one to two hours) or at a late stage (five to eight hours). Assuming an exponential excretory function, a clearance value could be calculated. The results were compared with the clearance values of a tubular excreted radiopharmaceutical (99m technetium-MAG3). Despite the different excretory mechanisms, there was a statistically significant correlation between the scintigraphic and contrast clearances at the later time (r = 0.85, p is less than 0.001). At the earlier stage, there was no signification correlation (r = 0.46, p is greater than 0.05). The correlation between the later values and the serum creatinin level was moderately significant (r = 0.55, p less than 0.05).

[Value of phlebo-scintigraphy for clarifying thromboembolic processes in the pelvis and legs]. / Wertigkeit der Phleboszintigraphie zur Abklärung von thrombembolischen Prozessen im Bereich der Becken-Bein-Etage.

In 64 patients suspected of having had pulmonary emboli due to thrombo-embolic disease, radionuclide venography (RNV) and contrast phlebography were carried out (84 examinations of extremities, 64 examinations of extremities and pelvis). Phleboscintigraphy proved informative in the thigh and in the pelvis. Around the knee, RNV was sufficiently accurate as a screening method. In the calf, RNV was of diagnostic value only in the presence of positive findings on scintigraphy.

[Computed tomographic findings in bronchial adenoma]. / Computertomographische Befunde beim Bronchialadenom.

The diagnostic value of CT was studied in 36 patients with histologically proved bronchial adenomas. Peripheral masses were found in 16% of the patients. Mediastinal metastases were detected at operation in 8 (22%) of these patients. Two patients showed distant metastases. We were not able to find reliable CT criteria for bronchial adenomas.

[Size and density determination by thin-layer CT in relation to structural diameter and the contrast of the surrounding tissue]. / Grössen- und Dichtebestimmung mit der Dünnschicht-CT in Abhängigkeit von Strukturdurchmesser und Umgebungskontrast.

The reliability of CT size and density measurements has been examined by using phantom measurements with constant examination and reconstruction parameters (Somatom DRH/Siemens). Ten plexiglass rods with diameters from 2 to 15 mm. were measured singly in (1) air, (2) isodense (146 Hu) and (3) hyperdense medium (985 Hu) using 2 mm. sections. In the isodense medium there was only small variation in density measurements (124 to 131 Hu). Measurements of size showed a maximum error up to -35%. Density measurements in the hyperdense medium produced raised values (197 +/- 17 Hu at 15 mm.). There was an even greater increase for rods smaller than 5 mm. Measurement of size was correct, as it was in air (maximum deviation 8%). Density measurements in air for diameters less than 6 mm. were significantly reduced.

[Quantitative and morphologic information value of the SPECT perfusion study of thoracic space-occupying lesions]. / Quantitative und morphologische Aussagekraft der Spect-Perfusionsuntersuchung bei thorakalen Raumforderungen.

The results of planar perfusion scintigraphy, SPECT and CT were evaluated quantitatively and compared with each other in 47 patients with thoracic tumours. SPECT was superior to conventional scintigraphy in respect of morphological information. Quantitative evaluation of the function data derived from SPECT permits a more detailed anatomical recognition of perfusion inhomogeneity due to the tumour and can distinguish between central and peripheral tumour growth. Comparison between CT and SPECT showed good morphological agreement between the two.

[Computed tomographic imaging of collateral pathways in stenoses of the large mediastinal veins]. / Computertomographische Darstellung von Kollateralbahnen bei Stenosen grosser Mediastinalvenen.

Scans of angio-computed tomography (CT) of 53 patients suffering from mediastinal space-occupying growths were reviewed: 16 patients showed stenosis of mediastinal veins with demonstration of subcutaneous venous channels, 17 showed an obstruction without collateral pathways and 20 patients had normal mediastinal vessels. Two-thirds of the cases with external vein compression were caused by bronchogenic carcinoma. The degree of obstruction in patients showing collateral circulation was between 70 and 100 percent and significantly greater than in patients without collaterals (40%). The most important collaterals bypassing the upper mediastinal veins are discussed.

[The value of computed tomography in the search for an unknown primary tumor]. / Die Wertigkeit der Computertomographie bei der Suche nach unbekanntem Primärtumor.

CT scans of 31 patients, who had been evaluated because of metastases of unknown origin, were reviewed. Diagnosis of the primary site was established in 18 of the 31 patients only. More than 18 patients had metastatic adenocarcinomas. CT scans were helpful in identifying an occult primary tumour in 6 patients; in 5 cases the primary location could not be detected by CT examination. In 2 patients CT scans considered a wrong organ to be the site of an unknown primary tumour.

[Synopsis of computed tomography, scintigraphy and bronchoscopy in the diagnosis of bronchial carcinoma]. / Synopsis von Computertomographie, Szintigraphie und Bronchoskopie bei der Diagnostik des Bronchialkarzinoms.

In 87 patients with histologically proven bronchogenic carcinoma, computerised tomography (CT) and bronchoscopy were performed to assess the accuracy of CT in detecting bronchial stenosis. Whereas patent airways and mainstem stenosis were recognised in 85% of the cases, the overall accuracy was only 57%. Furthermore, the results of both methods were compared to scintigraphy (ventilation, perfusion) to evaluate the functional impairment due to altered lung morphology and bronchial stenosis. With an increasing number of CT-diagnosed atelectatic or infiltrated segments an almost linear decrease in ventilation and perfusion values was observed. In comparison, bronchoscopy-diagnosed tumour stenosis resulted in decreased ventilation and perfusion data only if the lesion was centrally located.

[CT morphology and clinical diagnosis of thoracic space-occupying lesions in patients under 40 years of age]. / CT-Morphologie und klinische Diagnose thorakaler Raumforderungen bei unter 40jährigen Patienten.

83 patients with thoracic masses and aged under 40 years, who had been seen in a chest clinic, were examined by CT. They were classified according to their diagnosis and typical CT findings were analysed. Bronchial carcinomas showed predominantly radial extensions and air trapping. Malignant lymphomas and benign tumours usually showed smooth outlines and evidence of some fat content. Malignant mediastinal or neurogenic tumours frequently contained liquid portions and calcification. The CT diagnosis of lymphomas (seven cases), metastases (28 cases) and benign tumours (13 cases) presented no problems in view of the typical appearance and position of the tumours; classification of malignant mediastinal or neurogenic tumours (seven cases) was difficult. Inflammatory masses (14 cases) and bronchial carcinomas (14 cases) showed similar CT appearances.

[SPECT-3-D reconstructions of lung perfusion in patients with thoracic space-occupying lesions]. / SPECT-3-D-Rekonstruktionen der Lungenperfusion bei Patienten mit thorakalen Raumforderungen.

The present study deals with 3-dimensional reconstruction of lung perfusion examinations in 20 patients with thoracic masses. The images were obtained by single photon emission tomography (SPECT) and were compared with conventional scintigraphic images and with the CT findings. 3-D reconstructions proved superior to 2-dimensional images for the topographic demonstration of the affected lung segments. No additional information could be obtained concerning the extent of the mass. Use of this method is valuable for the preoperative estimation of pulmonary perfusion.

[Computed tomographic findings in 36 patients with space-occupying lesions of the thymus]. / Computertomographische Befunde bei 36 Patienten mit Raumforderungen des Thymus.

The CT examination of 36 patients with masses in the thymus (three thymus hyperplasias, 33 thymomas) were evaluated retrospectively. Three tumours in atypical positions posed problems in differential diagnosis from bronchial carcinomas and two cases with extensive pleural metastases had to be differentiated from pleural mesotheliomas. There were no certain morphological features on CT which indicated whether the mass was malignant. Eleven patients with thymomas had metastases; in seven of these they were extra-thoracic, with preference for supraclavicular lymph nodes, adrenals and the axial skeleton. Tumour progression and distant metastases were found particularly in malignant thymomas of the epithelial type. Calcification in a thymoma tends to indicate that it is malignant.

[The liquefactive behavior of bronchial carcinomas and their metastases from the radiological viewpoint]. / Das Einschmelzungsverhalten von Bronchialkarzinomen und ihren Metastasen aus radiologischer Sicht.

Necrosis in bronchial carcinomas and in their soft tissue metastases was studied in 368 patients by means of CT and ultrasound. In primary bronchial carcinomas (59 cases) there was clear correlation between tumour necrosis and the histology. There was a significant preponderance amongst squamous carcinomas, whereas small cell carcinomas rarely show radiologically visible necrosis (p less than 0.01). Amongst metastases in the liver (128 cases), central nervous system (164 cases) and suprarenals (23 cases) there was no correlation between histology and the recurrence of necrosis. Necrosis in deposits in suprarenals and in the brain depends on the size of the lesion and could be demonstrated in more than 50% of cases. Liver metastases show necrosis in less than 5% of the cases by the imaging methods used.

[Lung perfusion-ventilation scintigraphy in squamous cell carcinoma of the lung]. / Lungenperfusions- und Ventilationsszintigraphie beim Plattenepithelkarzinom der Lunge.

The effect of tumour size, as determined surgically, and tumour position, as determined by bronchoscopy, on ventilation and perfusion scintigraphy was examined in 53 patients with squamous cell carcinomas of the lung. The findings were compared with reduction in one-second-capacity. Central tumours were frequently associated with marked reduction in perfusion. In these patients there was a linear positive correlation between ventilation and one-second-capacity. The reduction in perfusion, and the need to measure this, became with more peripheral tumours. There was a correlation between ventilation and tumour size in patients with V/Q quotient of greater than 1.2. The results show that tumour size and position do not necessarily indicate operability. For planning surgery of central tumours, perfusion scintigraphy therefore occupies an important position.

Intravascular flow prior to and following angioplasty in peripheral vessels (arteries).

OBJECTIVES: The aim of this study was to assess mean values of velocities in peripheral arterial vessels prior to and following angioplasty in patients with peripheral arterial occlusive disease. Standard values are evaluated with the guidewire positioned proximal to the lesion, inside the lesion and distal to the lesion. METHODS: Twenty-five measurements were taken prior to and following angioplasty in 22 patients with peripheral arterial occlusive disease. The Doppler guidewire was inserted over a 5 French sheath and a Cobra catheter. During measurements, the catheter was totally pulled back and the sheath was placed as proximal as possible. RESULTS: Prior to angioplasty, the velocities in the arteries were 69 +/- 60 cm/second proximal to the lesion, 186 +/- 112 cm/second inside the stenoses and 47 +/- 36 cm/second distal to the lesion. The values increased to 97 +/- 105 cm/second, 89 +/- 89 cm/second and 83 +/- 72 cm/second, respectively. Proximal velocities were lower inside occlusions and increased more markedly compared to stenoses. CONCLUSION: The Doppler guidewire is a practical and valuable tool in assessing technical success after angioplasty of peripheral lesions. In successful angioplasties, no flow acceleration should be observed. Standard values were evaluated.

Evaluation of recurrent bronchogenic carcinoma by computed tomography.

Thirty-five patients with strongly suspected recurrent tumor of the lung and definitely positive computed tomography (CT) scan were reviewed. The patients had undergone surgery (group A, n = 17) or radiation therapy (group B, n = 18). TNM-staging of lung cancer in both groups revealed similar results. Small cell carcinoma (P less than 0.05), central tumors (P less than 0.003), and elderly patients (P less than 0.05) were more often found in group B. Disease-free interval was longer in patients with tumor resection (45.5 v 11.7 months, P less than 0.007) and depended on T-stage in irradiated cases (P less than 0.05). Local recurrence with or without mediastinal lymph node involvement occurred in all irradiated patients; 3 of 16 surgical patients showed isolated mediastinal lymph node enlargement without tumor relapse (not seen by plain chest roentgenographs). Plain films failed to detect nearly 20% of the space-occupying lesions, which could easily be identified by CT. In one patient the suspected tumor recurrence turned out to be a tuberculous infiltration. A second lung cancer (no tumor recurrence) was pathohistologically assumed in three of the resected cases with an interval from 10-181 mo after surgery. On the basis of these findings, CT-monitoring can be recommended when the patient is resected for cure. Some patients will benefit by an early diagnosis of a local-regional tumor recurrence when the time until the necessary secondary treatment may be shortened. Long-term survival may be achieved in a small group of these patients.

Pleural metastasis of malignant thymoma. A pitfall in the CT-diagnosis of pleural mesothelioma.

We report two cases with metastatic thymomas mimicking the CT feature of pleural mesothelioma.