Radiologia diagnostica最新文献

After a quantitative analysis of the number of patients with renal and biliary concrements in the GDR (1985: 17,000 and 67,000 hospitalizations) the principles of lithotripsy with extracorporally and intracorporally generated shock waves are described. The various principles of industrially manufactured devices (electric discharge, electromagnetic, piezoelectric, laser induced) are described including the associated methods for location of the concrements. Lithotripsy with extracorporally generated shock waves (ESWL) has replaced surgical removal of renal and urethral concrements and is increasingly used for biliary and pancreatic concrements. Intracorporally generated shock waves (often laser-induced and therefore cheaper than ESWL) are used less frequently, but can replace surgery for salivary concrements.

Advantages of digital radiography: Improved low contrast imaging; Image processing capability (on line or post-processing); Lower radiation dose for certain applications ("Dose variation"); Digital storage and data transfer; Only one exposure for different imaging characteristics; Optimised real-time image, "digital fluoroscopy" (DBR); Shorter examination times (DBR); Advantages for technically complicated exposures (intensive care, superpositions in the chest region, pediatry) (DLR); High dynamic range, which eliminates over or under exposure; Real time image processing and display (DBR). Disadvantages of digital radiography; Lower spatial resolution is limiting fine structure (max. theoretical resolution is 31p/mm for 1000 and app. 5 lp/mm for 2000 pixels image matrix); Spatial resolution depends from image intensifier diameter or screen format; Lower SNR (Signal to Noise Ratio) for reduced dose, increased noise impression for edge enhancement; Information losses for monitor camera (DBR) -hardcopies; Diagnostic capabilities are reduced by noise and low spatial resolution caused by certain applications (mammography).

In inhalation tracheobronchography with niobium powder in rabbits and a volunteer (physician), excellent contour bronchograms with detailed imaging of the structure of the mucosa were obtained. With methodically proper application the niobium particles of 20-40 microns do not penetrate into the alveoli and are quickly (within 1-5 days) eliminated from the bronchi. Investigations with mice have shown, that niobium powder is insoluble, does not irritate tissues and is not resorbed. It is also nontoxic.

The primary angiographic PTLA-success correlates with the angiodynographically measured blood flow. 24 hours after the treatment the measured flow values in the AFS and AP allow prognoses: 1. Flow volumes in the AP less than 15 ml/min do not allow successful PLTA-therapy. 2. Slight clinical improvement can be expected for flow values greater than 50 ml/min in the AFS and between 20 and 30 ml/min in the AP. 3. AP-values greater than 30 ml/min correlate in this pilot investigations with an excellent clinical result 4 months after intervention.

From histogram analysis the value of computed tomography for early detection of breast carcinoma or differentiation of benign and malign processes of the breast was evaluated. The results show, that CT is not applicable and gives no improvement of diagnostics.

For medical imaging in the pelvic region in female infertility/sterility several methods of investigation are available. Risk/benefit-considerations of the mentioned methods lead to a diagnostic gold-standard: Hysterosalpingography, laparoscopy, laparotomy. Hysteroscopy and sonography can be employed facultatively after hysterosalpingography.

Within a short term of 7 years percutaneous valvuloplasty of congenital and acquired stenosis, the cardiac valves and the great central vessels has significantly improved. If strict criteria for the selection of patients are used the method is an important addition to cardiac therapy, since it requires no thoracotomy, no heart lung machine surgery, no complicated interventional follow up treatment and gives remarkable short and long term results. Starting from a thorough study of 300 publications (4836 patients) a survey of possible complications, their frequency and in percutaneous valvuloplasty is given for various methods. The compiled data and commentaries give a negative survey and shall lead to a new evaluation of indications. Some types of interventions (primarily the percutaneous rupture of degenerative calcified stenosis of the aortic valve in higher age) will lead only by significant improvements of technique (stabilization of myocardiac circulation, prevention of extreme hypotonic phases, use of cutting and sawing instruments: valvuloplasty under cardioscopy?) to acceptable long term therapy results.

The most severe complications in transarterial closure of the ductus arteriosus persistens are problems with placing the plug into the ductus (misfit plug size/ductus size) and the flow of closure materials into the aorta after instable fixation of the plug. In such cases surgical intervention by arteriotomy or aortotomy for the removal of the plug becomes necessary. Transvenous dilatation of the ductus arteriosus persistens after recognizing unstable plus positions or difficulties in fixing the plug prevents the mentioned complications.

A method of contrast echography with albumin-carbon dioxide foam is reported. 140 women aged 20 to 60 were investigated. By filling the uterine cavity and in some cases the tubes the sagittal and longitudinal size of the uterus were determined and tumourous nodes in the uterine well were demonstrated. Contrast echography significantly widens the scope of ultrasonography of the uterus and its adnexa.

In 3,287 miners and other coal mine workers clinical and photofluorographic complex investigations of the respiratory system were carried out with the new method of photofluoropneumopolygraphy. Its use within the annual prophylactic investigation of the miners increases the effectiveness of the early detection of lung disease to 21.2%. The diagnostic accuracy of photofluorography for the evaluation of the adaptability of the organism in coal mine work and for respiratory dysadaptation disorder increases significantly. Photofluoropneumopolygraphy is recommended for the annual prophylactic lung investigation of coal miners.