Cysts in the cyst pattern

The increased knowledge of the natural course of cystic echinococcosis has also improved our understanding of the typical imaging features ("cysts in the cyst pattern") which can be nicely shown by imaging modalities, e. g., ultrasound and computed tomography. In the very early stages of echinococcosis without calcifications, ultrasound can depict the specific intralesional morphology in detail.

[Ultrasound-guided puncture of the subclavian vein to implant central venous ports]

PURPOSE

To assess the safety and efficacy of ultrasound guided puncture of the subclavian vein instead of blind puncture or surgical procedure. The advantages compared with implantation of brachial ports are demonstrated.

PATIENTS AND METHODS

In 41 oncologic patients the subclavian vein was punctured by ultrasound guidance in order to implant a port (34 left side, 7 right side). The study included 21 women and 20 men (range 34 - 79, mean 61 years). Imaging of the subclavian vein was performed with a 7,5 MHz linear ultrasound probe in B-mode and in colour doppler mode. Puncture was performed under ultrasound control (18 G, 45 mm needle when skin-vessel distance was < 3 cm, 19 G, 75 mm needle when skin-vessel distance was > 3 cm). In 27 patients a Bardport was implanted, in 14 patients a Vitalport (Cook). In three patients surgical port implantation failed. One of these patients had a partial thrombosis of the subclavian vein.

RESULTS

Technical success was 100 %. In one patient we first punctured the subclavian artery at the beginning of our series without any complication. All port systems could be implanted. There was one haematoma in the port pocket without any effect to the port function. In the three surgical patients subclavian vein puncture and portimplantation was successful.

CONCLUSION

Ultrasound guided puncture of the subclavian vein and port implantation by radiologists is a save procedure. A low risk approach to the subclavian vein is possible at any location. The long approach through the cubital vein with brachial port implantation is not necessary.

[The reduction of the extent of vascular lesions during angioplasty by the use of a sheath]

PURPOSE

To document the protection of the vessel using an introducer sheath.

MATERIAL AND METHODS

In eleven in situ specimens we compared in the inguinal vessel the macroscopic and histologic trauma to the vascular wall during antegrade percutaneous balloon dilatation either without or with a sheath.

RESULTS

Significant differences we observed regarding both the puncture site configuration and the puncture hole border, which were evaluated macroscopically. During the histological assessment we found only small intimal trauma in the puncture track in the group where a sheath had been used. Severe intimal damages and the media showed tears if no sheath had been used (100/36% vs. 0/64%).

CONCLUSION

It is evident that using a sheath during angioplasty reduces the risk of intimal damage and, consequently, of complications such as recurrent haematoma, stenosis at the puncture site or formation of aneurysms due to the puncture.

[Color-coded duplex sonography (angiodynography) in comparison with phlebography]

To verify the suspected diagnosis of deep thrombosis in the pelvic and/or the leg veins or to clarify the causes of pulmonary embolism, 84 patients were examined prospectively by color-coded duplex-sonography. The findings in the 103 legs examined were subsequently compared to those of an ascending phlebography. The deep veins from the region of the vena iliaca communis down to the lower leg were visualized, and blood flow, lumen and compressibility were checked. This procedure enabled the identification of totally occluding thrombi as well as partial thrombi with the circumfluent blood. The sensitivity of thrombus identification was 92.9%, the specificity was about 97% in the different segments. The results show that color-coded duplex sonography is a sensitive diagnostic instrument for follow-up in conservative therapy. Also, in postthrombotic changes, fresh clots can be identified for the most part. Color-coded duplex sonography can replace phlebography in most cases, if special attention is paid to regions which are difficult to visualize, such as the pelvic veins, the Hunter's channel and the veins of the lower leg.

Indications and results after Strecker-stent-application in iliac and SFA

We report on a study which has been performed during two consecutive time intervals on patients with complicated arterial obliterations, who were treated with percutaneous endoprostheses in order to stabilize the results obtained by the preceding balloon angioplasty. Eighty patients participated at this study, and 136 stents were implanted. A detailed analysis of the reocclusions respectively the stenoses shows that the precise placement of the stents and also the length of the stent in relation to the lesion is of utmost importance, in order to avoid reocclusions. The Strecker stents were lege artis placed in both time groups, and the increased occurrence of reocclusions, especially in the femoropopliteal region, was mainly due to the fact that only one stent length was available. Restenoses in the second group are, thus, considerably lower between 6 and 12 months, as the use of an adequate stent length was possible by then. The medical supplementary treatment of lege artis placed stents in the iliac arteries has no additional influence on the patency rate, while the medication with anticoagulants seems to have a rather positive effect on the patency rate in the femoro-popliteal region. The results, which have been obtained up to now, show that definite improvements are to be achieved by the use of stents, provided that their indication is being handled with utmost care.

[Evaluation of intrapulmonary round foci using thin-layer computed tomography]

100 patients with 122 round pulmonary lesions were examined preoperatively by CT, using either 8 mm or 2 mm sections. The most important findings were: radial extensions were seen on the fine sections in 95% of primary bronchial carcinomas (48 cases), in 60% of lung metastases (31 cases) and in 70% of chronic inflammatory lesions (24 cases), but they were not seen in benign tumours or hamartomas. Similar findings were observed for perifocal consolidation. Calcification was found in 80% of the tuberculomas (15 cases) and in 37% of the hamartomas (8 cases), but it also occurred in 15% of the primary bronchial carcinomas and in almost 13% of the lung metastases. Thin section CT provided more information than did 8 mm sections in 44% patients, concerning the outline of the lesion, and in 60% it was better at showing calcification. It was not possible to define a pattern of calcification which would distinguish benign from malignant lesions.

[Differential computed tomographic diagnosis of cavity-forming space-occupying lesions of the lung]

One hundred cavitating pulmonary foci were examined by CT; the appearances have been analysed and compared with the histological findings. Three types of disease have been characterised: bronchial carcinomas, lung metastases and benign lesions. Compared with benign lesions, malignant disease shows a significantly higher incidence of cystic or multiple cavities: thick cavity walls; radiation of tumour tissue; enlarged mediastinal lymph nodes; ipsilateral displacement of the mediastinum; intrapulmonary satellite foci and infiltration of the thoracic wall. Morphologically, tumours can be most easily distinguished from metastases by their ill-defined outer contours. Non-epidermoid primary lung tumours have a higher incidence of pleural effusions and other pleural reactions than have tumours of other origins. 80% of cavitating lung tumours are squamous cell carcinomas, the remaining 20% consist of adeno- and large cell carcinomas. Small cell carcinomas practically never show cavitation.

[Intra-arterial DSA versus conventional angiography in assessing the resectability of pancreatic and periampullary carcinomas]

Fifty patients were examined to determine whether intraarterial DSA can replace conventional angiography to assess the resectability of pancreatic and periampullary carcinomas. Intraarterial DSA yielded equivalent diagnostic information in 60% of the cases. As a result of contrast-enhanced visualisation of the splanchnic veins intraarterial DSA was superior to conventional angiography in 26% of the cases, whereas in 14% intraarterial DSA provided less information due to motion artifacts.

[Single-catheter technic for intra-arterial digital subtraction angiography of the aortic arch and selective imaging of the supra-aortic arteries]

A double-curve catheter with side-holes was used for intraarterial digital subtraction angiography of the aortic arch and selective angiography of the supraaortic arteries. Applying this technique the same catheter can be used in the majority of cases (approximately 75%) if aortic arch angiography is followed by selective catheterisation of the supraaortic arteries.