Biomedical subjects

R Braunschweig

Publications and source records attributed to R Braunschweig.

At least 19 recordsLinked to original sources

PubMed1999

[Kidney spiral CT. Indication, method, results].

The introduction on spiral computed tomography (spiral CT) has vastly enriched the methodological diversity of computer-tomographic scans. It allows for the recording of different perfusion or excretion stages of the kidney parenchyma of the urine draining paths by carrying out long-distance, phase-identical multiple examinations of the retroperitoneum. The description of the findings which are characterized by their local and contrasts behavior is possible. The following report describes the indications and technological process of kidney spiral CT using kidney-typical intravenous contrast media. Special emphasis is put on the advantages and limits of multiple phase spiral CT. Decisive preconditions are: 1. specific clinical query, 2. selection of the corresponding phase contrasts of the kidneys and uretra or bladder, 3. exact technical and temporal adjustment of the acquisition parameters. Scanning times are in the range of seconds. The overall examination can be carried out quick and without any major strain on the part of the patient. A sound proof and a general differentiation of focal kidney lesions can be derived from the acquired data. This is also true for kidneys and ureters findings. Bladder findings can be localized and differentiated according to stage. More than two "spiral acquisitions" should be carried out with re-straint taking exposure to radiation into account. Due to the sound registration of focal lesions, its capability of reproduction and its short-time examination, the spiral CT of the kidneys can be said to be the most effective current scanning method of the retroperitoneum following clinical examinations and sonography.

Female↗

PubMed1999

Assessment of gastric cancer: value of breathhold technique and two-phase spiral CT.

The purpose of this study was to evaluate the capabilities of subsecond spiral CT in detecting and staging of gastric cancer. Our study included 40 patients with endoscopically detected gastric carcinomas. Two-phase spiral CT was performed within one breathhold each. Distension of the stomach was achieved by intravenous application of scopolamine and drinking of 500 ml water. After bolus injection of contrast medium, scanning was performed in the arterial and venous phase. Gastric tumour extention and lymph node involvement was assessed. Gastric cancer was detected in 39 of 40 cases (sensitivity 97.5%). Location of the tumour was correctly assessed in all cases. In 31 of the 39 cases (79.4%) CT staging was accordant with pathological staging. One hundred two (70%) of 145 nodes infiltrated by tumour tissue were detected and 144 (42.8%) of 336 nodes free of metastatic involvement were found. The predictive values of positive and negative results for the detection of lymph node metastases were 67.1 and 75%, respectively. Spiral CT is recommended for staging of gastric cancer.

Adenocarcinoma↗

PubMed1999

Evaluation of spiral CT in staging of colon and rectum carcinoma.

The purpose of our study was to evaluate the capability of a subsecond spiral-CT scanner using two contrast medium phases in staging of colorectal cancer. In our study we included 37 patients with proven rectum or colon carcinoma. Spiral CT was performed following tap-water enema of the colon in the arterial and venous phases of contrast medium enhancement. Our results were compared with the findings of pathological examination after surgery. The tumor's size and extension were evaluated in the arterial and venous phases, the lymph nodes in the venous phase of the CT scan. The tumor was in the rectum (n = 14), sigma (n = 11), descending colon (n = 6), and cecum (n = 6). Two-phase spiral CT had a sensitivity of 97.2% in the arterial phase and 89.1% in the venous phase in detecting the carcinoma. The staging results were in the arterial phase in 30 of 37 cases (81.0%) and in the venous phase in 24 of 37 cases (64.8%) according to pathology. In 27 of 32 patients (84.3%) lymph nodes were detected. The correct classification of the N-stage was possible in 23 of 34 cases (67.6%). The combined use of arterial and venous phases in staging of colorectal cancer can improve the T- and N-stage classification in comparison with using only one contrast medium phase. The arterial phase is superior compared with the venous phase for local tumor staging and the venous phase is used for lymph node assessment.

Adult↗

PubMed1999

Diffuse metastatic infiltration of a carcinoma into skeletal muscle.

Skeletal muscle is one of the most unusual sites of metastasis from any malignancy. We report a patient with rapidly progressive contractures due to metastatic infiltration of a carcinoma of unknown origin into the skeletal muscle. This 61-year-old man presented with a 1-month history of rapidly evolving, painful restriction of mobility of his right arm and his legs. Computed tomography showed diffuse metastatic nodules in all muscles, particularly in the hip abductors. Muscle biopsy revealed extensive infiltration of the muscle with carcinoma cells.

Biopsy↗

PubMed1997

Digital radiography.Results of a survey (part A) and a consensus conference (part B)

Digital imaging (digital image intensifier radiography, storage phosphor/selenium radiography) is increasingly becoming commonplace in radiology departments for diagnostic purposes. Despite 10 years of experience, the advantages and disadvantages of those methods are still heavily discussed among users, financiers and prescribers. This paper is to offer additional arguments for a thorough and objective discussion. No further comments or interpretations have been added to this paper. This paper consists of two main parts, A and B. The first part deals with the results of a user survey, the other part presents the results, i. e. statements, of a consensus conference.

Journal Article↗

PubMed1997

[Digital radiography--results of a user survey (A) and consensus conference (B)].

Digital radiography is increasingly replacing conventional radiography in imaging. For some years now, the pros and cons of this new method have been subject to intense discussions. For further discussion, the present article describes the results of an inquiry among users and of a consensus conference held in March 1996 in Munich. Comments and interpretations have been omitted on purpose.

Attitude of Health Personnel↗

PubMed1997

Digital radiography. Results of a survey (part A) and a consensus conference (part B).

Humans↗

PubMed1996

[Digital radiography. Cost-benefit analysis].

Due to its high dynamic range and contrast discernibility, digital radiography offers substantial advantages compared with conventional film-screen systems. Moreover, further advantages can be assumed for radiation protection. Digital radiography also allows conventional image data to be included in PACS (Picture Archiving Communication System). These well-known advantages are faced with legal questions which are not yet settled. Cost effectiveness in using systems of digital radiography and PACS are also under discussion. By means of examining economic efficiency and cost analysis of digital radiography systems, economic effectiveness was assessed. This was also compared with conventional alternatives. As a result, it may be assumed that amortization is reached in three to four years. Based on lower costs for films, digital systems are more cost effective than conventional systems after this period.

Cost-Benefit Analysis↗

PubMed1996

Effects of varying filter kernel sizes on the image quality of interstitial lung diseases.

PURPOSE: The aim of the study was to optimize the postprocessing of digital luminescence radiographs of interstitial infiltrates of the lung. MATERIAL AND METHODS: Ninety-seven patients with established diseases of the lung parenchyma were examined: 514 pathological details were investigated, using a 200-speed screen-film system and a storage phosphor plate. In digital postprocessing, the size of the filter kernel (S) varied between S 5 and S 70. Based upon 32896 individual evaluations, the image quality was evaluated in multifactorial variance analyses. RESULTS: The digital standards were significantly inferior to the tested screen-film system. The large filter kernel S 70 and the small filter kernels S 5 and S 10, as well as an algorithm for edge enhancement, showed selective advantages in the depiction of nodular or small linear structures. For micronodular and linear structures, kernel sizes of S 20 and S 40 produced equally good results (p > 0.05). CONCLUSION: Whenever optimized postprocessing is involved, storage phosphor radiography is equal to a modern screen-film system and can be substituted for the latter without any loss of image quality; this is especially valid for the imaging of interstitial infiltrates of the lung.

Female↗

PubMed1995

[Quantification of variations in arm perfusion after plexus anesthesia with color doppler sonography].

The axillary brachial plexus block is a well-known technique for intra- and postoperative analgesia and sympathetic blockade in hand and microsurgery. The aim of this study was to show the influence of the axillary brachial plexus block on the blood flow as a side effect. METHODS. We used a colour-coded sonography unit (Toshiba) with a 7.5-MHz transducer. A total of 12 patients with no clinical signs of vascular diseases were enrolled in this study. We measured the peak blood flow velocity and the peak flow at the bifurcation of the brachial artery and vein and the proximal and distal radial artery before and after the plexus block. In addition, we were able to take the morphological aspects of the analysed vessels into consideration as we also used conventional sonography. This was done to detect any early signs of vascular malformation or arteriosclerosis, either of which might have affected the measurements. RESULTS. The average arterial peak blood flow after the plexus block was 1.9 times that before. On the venous side, the block effect caused an average increase of the blood flow to 8.6 times than before the block. In general, an additional and immediate effect of the block was a significant rise in blood flow velocity with an increase in cross-section area. CONCLUSIONS. The brachial plexus block combines two advantages: pain relief and pain management plus temporary sympathectomy. In conclusion, it prevents vasospasms and improves the circulation of the hand in patients undergoing reimplantation of limbs and those with nutritional disorders.

Adolescent↗

PubMed1995

[Double-contrast arthro-CT in diagnosis of shoulder instability].

Timeless and lesion-related treatment are important in the different shoulder instabilities in order to get a good functional result. Within the step-by-step programme of diagnostic possibilities the double contrast computerised arthrotomography is particularly indicated in recurrent posttraumatic and habitual dislocations, in subluxations as well as for clarification of causes of postoperative recurrence. Besides the documentation of skeletal changes (Hill-Sachs-lesion, Bankart defect), double-contrast arthro-CT offers the possibility to identify detachments of the joint capsule or labral tears. Between 11/90 and 9/93 we performed 38 double contrast arthro-CTs for recurrent shoulder instabilities. 35 men and 3 women were examined. The mean age of the sportive patients were 29 years. Preoperatively we diagnosed in 21 cases a recurrent posttraumatic, in 7 cases a habitual shoulder instability. Apart from one multidirectional and three posterior instabilities we found two cases of subluxation. In the meantime 24 patients were treated with an open stabilising operation of the shoulder. The operative findings were compared with the results of double contrast arthro-CT. In a total of 38 performed arthro-CTs we found labral tears in 4 cases, 14 labral dissections, and 10 times a complete labral discontinuity. 8 of 9 labrum dissections found intraoperatively were correctly identified on CT. One dissection was not even seen retrospectively on arthro-CT. Six of nine complete labrum discontinuities were seen on arthro-CT, three described as a dissection. All capsular detachments and bony Bankart lesions found on CT were confirmed intraoperatively.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1994

[Transvenous sonography of the peripheral arterial vessels. The initial clinical results].

Intravascular ultrasound with 20 MHz/6.2-French transducer systems was used for arterial imaging via a transvenous approach. In 20 patients suffering from chronic arterial occlusive disease, 15 iliac arteries were evaluated during diagnostic angiography and 5 femoropopliteal arteries during balloon angioplasty (n = 3) and laser-assisted angioplasty (n = 2), respectively. Transvenous sonography did not allow differentiation of arterial wall layers and determination of vessel diameters as is usually possible during intraarterial sonography. Visualisation of iliac arteries was incomplete. In femoropopliteal vessels, guide wires could be detected within the arterial lumen but not in complete occlusions. Delivery of pulsed laser energy induced bright echoes near the catheter tip within a distance of 1-2 cm. Transvenous sonography is insufficient for monitoring of peripheral angioplasty; however, improved imaging quality might be possible at lower frequencies.

Aged↗

PubMed1994

[CT and HR-CT in the diagnosis of pulmonary complications of bone marrow transplantation].

The aim of this prospective study was to compare conventional and high resolution CT for demonstrating pulmonary complications. 23 patients treated by bone marrow transplantation were included in the study between December 1990 and August 1991. These patients were examined radiologically at regular intervals following the transplants. In 9 patients lung changes were detected by CT: there were pneumonic infiltrates, including one CMV pneumonia, two cases of mild parenchymal fibrosis, two cases of extensive lung fibrosis and one of miliary tuberculosis. The advantages and disadvantages of conventional and high resolution techniques are discussed in relation to our findings.

Adult↗

PubMed1994

[Evacuation proctography: physiological variability and clinical relevance of the anorectal angle and the position of the pelvic floor].

Evacuation proctography is an important imaging method for the investigation of abnormalities of defecation. For this procedure, the most commonly carried out measurements are the ano-rectal angle and the position of the pelvic floor. The given mean values and the physiologically acceptable deviations vary just as much as the perceived clinical value of these measurements. 173 evacuation proctograms were evaluated in a prospective study; the subjective abnormalities were correlated with clinical findings. No significant correlation between the measurements from the proctograms and the clinical findings could be determined. The clinical relevance of these measurements is, therefore, uncertain.

Adult↗

PubMed1994

[The monitor findings of digitalized conventional wrist x-rays].

The study aimed at proving the reliability of monitor systems with the matrix of 1024 x 768 for the detection of scaphoid fractures compared to conventional X-ray. Moreover, we were interested in the significance of procedures of digital imaging post processing, depending in particular on the experience of investigators. 5 investigators with different levels of experience analysed 57 X-rays of the wrist. They compared conventional X-rays with images on a high screen monitor system after the digitalisation of these X-rays by a CCD-scanner and analysed untreated and treated images. A 5-point scale ROC analysis was used for evaluation. The analysis covered a total of 1740 evaluations. The untreated images seen on the monitor system proved slightly better than conventional X-rays. Post-processing has no evident advantage over untreated images. Differing levels of experience had no effect whatsoever on the identification of findings.

Carpal Bones↗

PubMed1994

[Use of digital photoluminescence radiography in traumatology. Report of experiences].

For more than 1 year we have had the opportunity of using a digital photoluminescence radiography system that allows documentation of the radiological findings on a high-contrast scale. In addition to chest X-rays this technical unit has been used to document skeletal findings in the skull, the cervical spine and the shoulder. In all, 211 cases have been evaluated in which digital and conventional X-rays have been taken during treatment. Using a 5-step confidence scale, two experienced investigators have evaluated and compared the digital and conventional X-rays. In respect of image quality, bone outline, and structure and identification of findings, digital documentation has proved at least as good as conventional documentation, and even superior in the case of shoulder X-rays. Improved image quality is caused by the superior bone outline. Therefore, we recommended digital photoluminescence radiography as a routine procedure for the documentation of findings in the skull, cervical spine and shoulder. Repeated investigations will become unnecessary and it will be possible to cope with large numbers of patients.

Adolescent↗

PubMed1994

[Ovarian carcinoid tumors: immunohistochemical and ultrastructural study of 8 cases].

Eight ovarian carcinoids, 4 trabecular and 4 strumal have been studied immunohistochemically for polypeptide hormones; three of them were also examined with the electron microscope. Seven of eight cases were positive for at least one polypeptide hormone. The trabecular parts of the 4 cases of strumal carcinoid were positive for pancreatic polypeptide. As the vesicular regions of these 4 cases were positive for thyroglobulin and for pancreatic polypeptide, we suspect the existence of "hybrid" thyroid and neuroendocrine cells. The electron microscopic examination revealed: the cell in the insular carcinoid had no distinct polarization and contained electron-dense granules of varying shape; in the trabecular part of the strumal carcinoid the cells were polarized and contained round electron-dense granules.

Adult↗

PubMed1993

[Dynamic 3D imaging of peripheral vessels using color-coded Doppler ultrasound].

3-D reconstructions are established as post-processive methods in CT and MRI. However, these methods permit assessment of morphological findings only. To uncover functional relations on the basis of ultrasound would also be of paramount interest. For this purpose a specific method was developed for the acquisition and time-coded 3-D reconstruction in the diagnosis of peripheral vessels, in particular of the extracranial carotid artery. An imaging device (Acuson 128 XP) with a 7.5 MHz probe, a PC-controlled stepping motor and an imaging system (Kontron Mipron) was used. Data acquisition was performed scan-by-scan in a transverse plane with a slice thickness of 1 mm along the vessel. In every slice position multiple ECG-trigger delays during the cardiac cycle were used. Data were transferred to the imaging system via videosignal. In preliminary clinical application this dynamic 3-D reconstruction method yielded good spatial resolution of the complex physiological flow phenomena in the carotid bifurcation.

Blood Flow Velocity↗