[Fracture and embolization of a central venous port catheter without prior compression between the clavicle and the 1st rib]. / Bruch und Embolisation eines zentralvenösen Portkatheters ohne vorherige Kompression zwischen Klavikula und erster Rippe.

A central venous port catheter inserted infraclavicularily via the subclavian route may be compressed by the clavicle and the adjacent first rib. It's appearance on chest x-ray has been previously described as the 'pinch-off phenomenon' and requires the removal of the catheter due to a significant risk of fracture. We report the case of a catheter fracture without prior evidence of pinch-off. The free catheter fragment was embolized into the right atrium and caused pericardial effusion. Percutaneous removal of the fragment was attempted but failed and thus open heart surgery with a cardiopulmonary bypass was required. The myocardial lesion caused by the catheter was sutured.

[Dental CT: examination method, radiation dosage and anatomy]. / Dental-CT: Untersuchungstechnik, Strahlenbelastung und Anatomie.

Traditionally oral surgeons and dentists have evaluated the jaws using intraoral films and panoramic radiographs. The involvement of radiologists has been limited. In the past few years dedicated CT-software-programs developed to evaluate dental implant patients have provided a new look at the jaws. The complex anatomy is described and identified on human skulls and on axial, panoramic, and cross-sectional images. With this anatomic description Dental-CT-scans are used to demonstrate the anatomy of maxilla and the mandible. An overview of the technique of Dental-CT is provided, furthermore the radiation dose of different organs is explained. Suggestions to reduce these doses by simple modifications of the recommended protocols are given.

[Diagnostic angiography in life-threatening colonic hemorrhage in Crohn disease]. / Angiographische Diagnostik einer lebensbedrohlichen Kolonblutung bei Morbus Crohn.

Life-threatening colonic hemorrhage is a very rare condition in Crohn's disease. Lower gastrointestinal hemorrhage in Crohn's disease occurs in 0.6-2.5% of cases. In a patient presenting with severe gastrointestinal bleeding after ileocolectomy, mesenteric angiography provided precise localisation of the bleeding site in the area of the splenic flexure.

[Mechanical high speed analysis of acute thromboembolic occlusions of t he popliteal artery. Initial experiences with the Amplatz thrombectomy catheter]. / Mechanische Hochgeschwindigkeitslyse von akuten thromboembolischen Verschlüssen der A. poplitea. Erste Erfahrungen mit dem Amplatz-Thrombektomie-Katheter.

PURPOSE: To determine the efficacy and the benefits of the Amplatz Thrombectomy Device (ATD) in acute thromboembolic occlusions of the popliteal artery. PATIENTS AND METHODS: 15 Patients (mean age 66 years) presenting with acute thromboembolic occlusions of the popliteal artery underwent mechanical thrombolysis with the ATD. The duration of symptoms was 1-22 days, mean length of occlusion was 7 cm (5-10 cm). RESULTS: Mechanical thrombolysis was successfully performed in 14/15 patients. The mean running time of the ATD was 4 minutes. The ATD failed in one patient with a 22-day history of popliteal artery occlusion. Remaining stenoses after ATD-thrombolysis were treated with percutaneous transluminal angioplasty (n = 3): pulse spray thrombolysis with urokinase was performed in two patients, in one patient aspiration thromboembolectomy with a 5F-catheter was performed to remove a small embolus from the anterior tibial artery. The ankle-brachial-index increased from 0.62 +/- 0.25 to 0.9 +/- 0.15. CONCLUSIONS: The ATD seems to be a safe, simple, and fast-acting mechanical device from mechanical thrombectomy in the lower limbs. No complications were seen.

[Thrombosis of the upper thoracic inflow vessel. Spiral CT and 3-D reconstruction]. / Thrombose der oberen thorakalen Einstrombahn. Spiral-CT and 3-D-Rekonstruktion.

Spiral-CT-Depiction and 3D-Reconstruction: A patient complaining of upper thoracic inlet syndrome after thyroidectomy underwent contrast-enhanced spiral-CT. Coronal reconstructions and three-dimensional reconstructions were used to generate phlebographic images of the thoracic inlet veins thrombosis. The diagnosis of thrombosis was confirmed by phlebography.

Radiodense concretions in maxillary sinus aspergillosis: pathogenesis and the role of CT densitometry.

The purpose of this study was to investigate by CT the origin of radiodense maxillary sinus concretions and whether CT densitometry is effective in the prediction of maxillary sinus aspergillosis and in the differentiation of the origin of these concretions. In a prospective study in 21 patients with radiodense maxillary sinus concretions detected by radiography, a preoperative CT study of the paranasal sinuses and the concretions was undertaken. Additional scans of the upper alveolar ridge were also performed. Radiological findings were compared with clinical symptoms and with CT findings, especially CT densitometry of the sinus concretions and dental root-filling material. All patients underwent a functional Caldwell-Luc operation; histological and microbiological examinations were performed. Fifteen of the 21 patients (71.4%) with radiodense concretions had a histological and microbiological diagnosis of sinus aspergillosis. The sinus concretions had CT densities higher than 2000 HU (Hounsfield units) in 15 patients and lower than 2000 HU in 6. fourteen of 15 patients (93.3%) with concretions having CT densities higher than 2000 HU had a postoperative diagnosis of maxillary sinus aspergillosis. The mean CT density of the sinus concretions in patients with maxillary sinus aspergillosis was 2868 HU (range 1870-3070 HU), and in patients without aspergillosis was 778 HU (range 228-2644 HU). The mean CT density of the dental root-filling material was 2866 HU (range 2156-3070 HU). Paranasal sinus CT with CT densitometry of a sinus concretion has a higher accuracy than standard radiography and clinical findings in the prediction of maxillary sinus aspergillosis (93.3% vs 71.4%). CT densitometry helps to confirm the dental origin of maxillary sinus concretions and to explain a possible dental pathogenesis of maxillary sinus aspergillosis.

Imaging of unerupted and displaced teeth by cross-sectional CT scans.

Thirty-six impacted and displaced teeth in 29 patients were examined radiographically by using orthopantomography (OPG) and computed tomography (CT). CT scans were obtained by using both a conventional program and a dental CT software program. The radiographic images obtained were compared for visualization of the internal position, inclination of unerupted teeth, and diagnosis of contact and doubtful or clearly visible resorption of adjacent roots. Both CT methods were superior to OPG. As far as the internal position and inclination of the impacted teeth, direct contact, and clearly visible resorption are concerned, the conventional CT program yielded the same information as the dental CT program. However, the exact proportional cross-sectional views obtained by dental CT yielded significantly (P < 0.01) better information about doubtful root resorption in adjacent teeth than did conventional CT.

[Improved imaging of mandibular cysts using dental-CT]. / Verbesserung der Darstellung von Unterkieferzysten mittels Dental-CT.

The purpose of this study was to evaluate orthopantomography and a newly developed CT software package (Dental-CT) in the preoperative assessment of mandibular cysts. In this study 16 cysts in 13 patients were examined radiographically by orthopantomography and dental-CT to reformat the axial scans into truly cross-sectional views perpendicular to the anatomical axis of the jaw. The obtained images were compared for visualisation of the alveolar canal, the mandibular anatomy and the cortical involvement. Dental-CT proved superior for establishing a correct radiographic diagnosis and was rated significantly (p < 0.001) higher with regard to examined points. Dental-CT has to be considered the method of choice in the preoperative evaluation of mandibular cysts providing detailed anatomical information needed for the further management. Radiation exposure remains within an acceptable range.

Localization of pulmonary nodules before thoracoscopic surgery: value of percutaneous staining with methylene blue.

OBJECTIVE: Video-assisted thoracic surgery (VATS) is a new procedure that makes it possible to see the intrathoracic organs and to resect pulmonary nodules without thoracotomy. Preoperative localization of small nodules that may not be visible or palpable during VATS is desirable. Percutaneous placement of spring hookwires is widely used to localize pulmonary nodules before VATS; infrequently, the adjacent lung parenchyma is also stained with methylene blue. The purpose of this study was to evaluate the effectiveness of methylene blue staining of pulmonary nodules without placement of a hookwire. SUBJECTS AND METHODS: Fifteen pulmonary nodules in 15 patients were localized preoperatively under CT guidance by using techniques identical to those for CT-guided fine-needle aspiration of pulmonary nodules. Approximately 0.3 ml of methylene blue dye was injected into the nodule with a 22-gauge Chiba needle to stain the nodule, the needle pathway, and the visceral pleura. In two patients, a hookwire also was placed. All patients had solitary nodules in which transbronchial or transthoracic biopsy had been unsuccessful. The mean nodule diameter was 16 mm (range, 8-33 mm), and the mean distance to the nearest pleural surface was 10 mm (range, 0-21 mm). The localization procedure required a mean of 32 min (range, 18-47 min). RESULTS: All 15 nodules were stained successfully either in the center or within the margins; the two hookwires were found to be displaced. In three cases, pulmonary hemorrhage occurred as a complication of the percutaneous staining procedure: in one case, subsequent conversion to thoracotomy was necessary owing to pulmonary hemorrhage and additional pleural bleeding during VATS, which resulted from puncture with a trocar directly into the pleural adhesions. Anticipated complications, such as pneumothorax, occurred in five patients; one patient had pleuritic pain, but none required treatment. In one patient, conversion to thoracotomy was done so that an adenocarcinoma could be treated by means of a lobectomy. In two others, thoracotomy was done because of problems with technical devices. CONCLUSIONS: Percutaneous staining of pulmonary nodules is an accurate technique for localizing nodules before VATS. The procedure is easily and safely performed, and it obviates wire-related complications, such as severe pleuritic pain.