PubMed Health⌕ Search

Biomedical subjects

C Sohn

Publications and source records attributed to C Sohn.

At least 109 records · Page 6Linked to original sources
PubMed1989

[The effect of body position on uterine blood flow in the 3d trimester of pregnancy].

Uterine vessels of 20 women with uncomplicated pregnancy between the 34th and 38th week of gestation were examined by means of Duplex sonography and a "simple" Doppler ultrasound device without sectional view and spectral analysis. Blood flow in several uterine vessels was recorded in various body positions: lying, sitting on a bench, standing, and - with some of the patients - in a position sitting on a so called "Variable Balance Chair". The relationship between the systolic and diastolic levels, as well as the shape of the Doppler curve, led to the Doppler parameters used. The Doppler parameters pointing to the best perfusion were found in the lying position, and sitting on the "Variable Balance Chair". Uterine perfusion seemed to be significantly decreased at the regular sitting, and in the standing position. Likewise, the shape of the Doppler curves indicated higher resistance in the blood vessels in the standing and the regular sitting position. The observations show that there are other factors that influence the momentary uterine perfusion besides uterine contractions. These results seem to be useful for the management of foetal growth retardation.

Blood Flow Velocity↗
PubMed1989

[Possibilities of 3-dimensional ultrasound imaging].

This is a report on the clinical use of sonographic imaging. Experimental studies have shown that parallel sonographic sections are available only in vitro, which means no in-vivo three-dimensional reconstruction is possible as it is with magnetic resonance and computed tomography. The idea that a coordinated sequence of sections can be obtained by spatial rotation of the plane of sound so that the individual sections differ from one another by defined angular distances, enables three-dimensional reconstruction of sonographic in-vivo sections. A transducer was constructed that enables the production of sonographic sections rotating around a fixed center of rotation. Its clinical usefulness was tried and confirmed in the imaging of early pregnancies, benign and malignant carcinomas of the breast, and in imaging a gallbladder with a solitary gallstone. Three-dimensional imaging can be achieved either as a ring-shaped structure or with a continuous surface. This points to the possibility of diagnosing malformations early in pregnancy if the number of sections is sufficiently high. In tumour imaging the malignant tumour seems to be clearly distinguishable from the benign one; three-dimensional diagnosis is likely to furnish important additional criteria in diagnosis. Further clinical studies will have to verify this.

Breast Neoplasms↗
PubMed1989

[Effect of parity on the venous system of the leg].

Pregnancy is known to be an important aetiological factor of varicose veins. How much this can be attributed to gestation is still controversially discussed. This problem was investigated using three non-invasive methods--Ultrasonography, Venous-Occlusion Plethysmography (VOP) and Light-Reflexion-Rheography (LPR). We found no significant differences between the group of primipara and multipara with relation to the venous morphology and the venous function in the legs. Only the distensibility of the venous wall of the multipara group was slightly increased in comparison to the group of the primipara. These results were found by VOP and LRR simultaneously. Varicosis is therefore caused mainly by the first pregnancy, whereas the subsequent pregnancies do not show remarkable changes of the status quo. Concerning the sensitivity of the methods mentioned above, ultrasonography alone can give easy and quick information. In the case of pathological findings, the indication for more complex investigations (VOP and LRR) can be established.

Female↗
PubMed1989

[Prerequisites for the clinical application of 3-dimensional ultrasonic imaging].

After satisfactory experimental results with three-dimensional data acquisition and presentation of the kidney in vitro, we wanted to show how our technique could be used for medical application in vivo, such as ultrasonic 3D reconstruction of organs. The sector scans were taken by rotating the scan head 10 degrees in any direction around the length of the axis. The organ was scanned with 18 images and reconstructed. The digital images, using the organ contours, allowed 3D reconstruction of the original organ, relying on the computer memory. The first results in reconstructing uteri show how this scan head can be used in combination with the computer programs for medical application. For the first time, it has become possible to present computer-generated views of an organ cross-section that has been impossible to obtain by means of traditional ultrasound techniques. Recent experiments using this method show new ways of diagnosing tumors.

Adult↗
PubMed1988

[Three-dimensional imaging in ultrasonic diagnosis. Initial results].

A new method of three-dimensional (3-D) reconstruction of 2-D ultrasound images of the kidney is described. It is based on a coordinated spatial reconstruction of sequential cross-sectional images. The ultrasound head is moved longitudinally between two rails (parallel sections) and rotated. With a suitable computer program and contouring of each cross-section (so that the organ limits are defined for the computer) these cross-sectional pictures can be reconstructed into 3-D organ images. The kidney can then be presented spatially either as a binary picture or with closed surface. Ultrasound investigators are still unaccustomed to colour reproduction of 3-D reconstructed organs. It remains to be seen whether the method is valuable in routine clinical use.

Color↗
PubMed1988

[Sonography as a screening examination method of the venous system in pregnancy. Comparative studies of the arm and leg vein system].

Comparative studies were conducted during the third trimenon of pregnancy between the 36th and 40th weeks of gestation and on the seventh day after delivery, at the venous system of the legs (vena iliaca, v. femoralis and v. poplitea) and at the venous system of the arms (v. brachialis). A marked reduction of the venous diameters was seen on the legs, whereas no difference was found in the venous system of the arms between both times of measurement. This points to the haemodynamic effect of the pregnant uterus, providing an obstacle to the flow of blood from the venous system of the legs. After delivery there is a relatively higher extensibility of the veins of the leg compared with the measurements in the third trimenon. This may be due on the one hand to the long-lasting overextension during pregnancy, and on the other hand also to the hormonal and enzymochemical changes that take place even during the puerperium. Doppler sonography of the v. femoralis showed clearly that the foetus obstructs blood flow from the venous system of the legs. Sonography seems to be able to visualise direct the changed morphology of the veins during pregnancy and to indirectly yield information on the extensibility of the venous system eg during standing, thus demonstrating in what way the venous system functions in a particular condition. Hence, sonography of the venous system of the legs during pregnancy should be used as a screening method wherever it is essential to discover extreme venous dilatations well in time and to initiate compression treatment.

Arm↗
PubMed1987

[Meniscus sonography--alternative to invasive meniscus diagnosis?].

Sonographic visualization of the meniscus as well as the detection and evaluation of its lesions presupposes use of the 7.5 MHz transducer of a sector scan. All lesions applied by means of a scalpel to cadaver knees could be pictured and evaluated in this way. In a clinical study, there was agreement between sonographic and surgical findings in 86 out of 91 patients (94%). The arthrography carried out in addition in 50 of these patients had a lower precision (88%) than sonography (98%). Agreement between the results of sonography and arthrography was found in 87 out of 98 patients (89%). The complete freedom from risk and high precision support the application of sonography in diagnosis of meniscus lesions. It can thus replace arthrography in this indication.

Arthrography↗
PubMed1987

[Sonography of the meniscus and its lesions].

It is the considered opinion of the authors that meniscus sonography can largely replace arthrography. This opinion is based on their detailed examinations and studies. Sonographic visualisation of all lesions produced by a scalpel was demonstrated using knees of corpses. Even cracks having the fineness of a human hair were visualised by sonography. A comparison between sonographic and surgical findings in meniscus lesion yielded in 82 patients an agreement of 95.1%. In 47 patients it was possible to prove that sonography was more accurate than arthrography as far as diagnosis was concerned. A comparison of 94 sonographically and arthrographically established findings yielded agreement in 89% of the cases. Sonography is suitable for meniscus imaging especially on account of the good imaging reproducibility of meniscus morphology; through safe detection of a pathological process in the meniscus; through the safe presentation of lesions; through the accurate imaging of all parts of the meniscus; and, furthermore, through the invaluable advantage of noninvasiveness, freedom from pain and hazards; and, last but not least, rapid manipulation and unlimited repeatability.

Arthrography↗
PubMed1987

[Non-invasive diagnosis of the venous system of the leg in pregnancy].

During pregnancy one should largely avoid invasive and radiological diagnostic methods. However, real-time sonography and venous occlusion plethysmography yield non-hazardous information on venous morphology and venous function. It became possible to demonstrate by means of these examination methods that the diameters of the veins are enlarged in pregnancy compared to the situation post partum. The difference in significant. Venous occlusion plethysmography points to a deterioration of venous function post partum, since the difference to the values in the third trimenon is not significant. Venous function measurement often pointed to the existence of an obstacle to flow during pregnancy, whereas sonographically a dilatation of the veins was revealed the existence of an obstacle to flow represented by the pregnant uterus. Hence, it appears meaningful to combine both investigation methods to confirm the occurrence of venous changes during pregnancy.

Blood Flow Velocity↗
PubMed1986

Comparison of 32P therapy and sequential hemibody irradiation (HBI) for bony metastases as methods of whole body irradiation.

We report a retrospective study of 15 patients with prostate carcinoma and diffuse bone metastases treated with sodium 32P for palliation of pain at Downstate Medical Center and Kings County Hospital from 1973 to 1978. The response rates, duration of response, and toxicities are compared with those of other series of patients treated with 32P and with sequential hemibody irradiation. The response rates and duration of response are similar with both modalities ranging from 58 to 95% with a duration of 3.3 to 6 months with 32P and from 75 to 86% with a median duration of 5.5 months with hemibody irradiation. There are significant differences in the patterns of response and in the toxicities of the two treatment methods. Both methods cause significant bone marrow depression. Acute radiation syndrome, radiation pneumonitis, and alopecia are seen with sequential hemibody irradiation and not with 32P, but their incidence can be reduced by careful treatment planning. Hemibody irradiation can provide pain relief within 24 to 48 h, while 32P may produce an initial exacerbation of pain. Lower hemibody irradiation alone is less toxic than either upper hemibody irradiation or 32P treatment.

Bone Neoplasms↗
PubMed1984

Efficacy of ceftizoxime administered twice daily in hospitalized patients with respiratory tract infections.

The efficacy and safety of ceftizoxime administered twice daily were evaluated in 215 hospitalized patients with documented lower respiratory tract infections. The majority of patients received 1 to 2 gm of ceftizoxime intramuscularly or intravenously every 12 hours; the mean dosage was 2 gm/day, and the mean duration of therapy was 8.9 days. Clinical cure was achieved in 204 (95%) of the 215 patients with lower respiratory tract infection. One hundred and thirty-eight patients were both clinically and bacteriologically evaluable. The clinical response rates, by organism, were: Streptococcus pneumoniae, 100% (50/50); Haemophilus influenzae, 96% (25/26); gram-negative bacilli (Escherichia coli, Proteus mirabilis, Enterobacter sp, Serratia sp, Pseudomonas sp, Klebsiella sp, Citrobacter sp, and Morganella morganii), 86% (32/37); and Staphylococcus aureus, 92% (12/13). In the other 77 patients with clinical symptoms, no pathogen was isolated or insufficient follow-up data were collected to assess bacteriologic response. Adverse reactions, which were infrequent, were similar to those reported in other US trials of the drug. The findings indicate that ceftizoxime, 1 to 2 gm BID, is effective and safe in the treatment of lower respiratory tract infections in hospitalized patients. This low-dose regimen can significantly reduce the cost of cephalosporin therapy.

Adolescent↗
PubMed1984

Five cephalosporins: pharmacokinetics and their relation to antibacterial potency.

In a group of adult volunteers, pharmacokinetic profiles of five cephalosporins were correlated with their minimal inhibitory concentrations (MICs90) against Staphylococcus aureus, Streptococcus pyogenes, Streptococcus pneumoniae, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, and Enterobacter aerogenes. Subjects received the following intravenous regimens in a randomized, crossover fashion: (1) 0.5 gm, 1 gm, or 2 gm of cefazolin; (2) 2 gm of cephalothin; (3) 1 gm of cephapirin; (4) 1 gm of cefoxitin; or (5) 0.5 gm of cefamandole. The 500-mg dose of cefazolin produced serum concentrations that exceeded those of any of the other cephalosporins at 0.5, 1, 2, 4, and 6 hours after administration. The area under the curve for this dose of cefazolin was at least twice that of any of the other antibiotics. Two hours after a 500-mg dose of cefazolin, serum levels exceeded the MIC90 for all seven groups of pathogens; at six hours, the 500-mg dose of cefazolin continued to achieve serum levels above the MIC90 against the majority of bacterial groups. In contrast, at two hours after administration none of the other cephalosporins maintained serum levels above the MIC90 for all pathogens; at six hours, the levels of cephapirin were adequate to inhibit the two streptococci, but serum levels of all other cephalosporins were inadequate to inhibit any of the pathogens. These data indicate that a 500-mg dose of cefazolin maintains serum levels above the MICs90 longer than any of the other cephalosporins tested and support the use of a 500-mg dose of cefazolin every eight hours for surgical prophylaxis and treatment of most community-acquired infections. Such a comparatively low dosage offers substantial savings to both patient and hospital.

Adult↗
PubMedDate not supplied

[Intercellular adhesion molecular 1, a diagnostic serum marker in chorioamnionitis, pre-eclampsia and HELLP syndrome].

INTRODUCTION: Chorioamnionitis and pregnancy-induced hypertension both are extremely feared complications of human pregnancy. Activation or disturbance of normal endothelial cell function may be involved in the pathogenesis of both kinds of disease. The aim of our study was to compare the diagnostic value of soluble intercellular-adhesion-molecule-1 (ICAM-1) with that of C-reactive protein (CRP) and white blood cell count for the detection of chorioamnionitis in patients with preterm labor. In addition, we examined if concentrations of ICAM-1 were also increased in case of preeclampsia or HELLP-syndrome. MATERIALS AND METHODS: ICAM-1, CRP and leucocyte count were estimated in 50 cases of normal term delivery, 97 cases of uncontrollable preterm labor, 16 cases of preeclampsia and 9 cases of HELLP-syndrome before delivery. RESULTS: From 97 women delivering preterm, chorioamnionitis was histologically confirmed for 48 women. Maternal serum levels of ICAM-1 (p < 0.001), CRP (p < 0.001) and leucocyte count (p < 0.02) were significantly higher in the group of preterm delivering patients (< 37 weeks gestation) with histologically confirmed chorioamnionitis in comparison to preterm delivering patients in the absence of chorioamnionitis. In the group of patients delivering preterm (< 37 weeks gestation) because of preeclampsia or HELLP-syndrome, ICAM-1 (p < 0.001), as well as CRP (p < 0.006) concentrations were also significantly increased in comparison to patients delivering preterm in the absence of chorioamnionitis. CONCLUSIONS: Elevated levels of ICAM-1 in the serum of pregnant women may be considered as an important risk factor for the development of complications in pregnancy associated with inflammatory induced changes of maternal endothelial cell functions.

Adult↗
PubMedDate not supplied

[New ultrasound simulation system: a method for training and improved quality management in ultrasound examination].

PURPOSE: Although ultrasound examination became almost indispensable in prenatal diagnosis as well as in gynecological examination, there are still a lot of deficits in the quality management of medical education. We present a "ultrasound simulation system", that makes it possible to simulate a complete ultrasound examination. The system is able to simulate all imaginable kinds of ultrasound examination. MATERIAL AND METHODS: At the Department of Gynecology and Obstetrics of the "Medizinische Hochschule Hannover" 115 banks of normal and 29 banks of pathologic volumes were scanned and stored into our newly developed "ultrasound simulation system". 7 physicians had to examine 10 "virtual" cases each; we evaluated the incidence of positive and negative results. Furthermore, the physicians had to evaluate the quality of visualization with a score. RESULTS: 12 of 14 malformations were identified as "fetal anomalies", whereas 2 fetal anomalies could not be identified correctly. All 56 healthy fetuses could be identified to be normal. The quality of visualization was regarded to be good in 62 cases, sufficient in 6 cases and poor in 2 cases. CONCLUSION: The "ultrasound simulation system" enables users to test and improve their levels of skill to detect pathologic findings in gynecological and obstetrical examinations. At the same time the system gives the instructor the possibility to test the quality of medical examinations. The integration of ultrasound training with an ultrasound simulation system into medical education should be discussed to improve the general level of skill in gynecological ultrasound.

Computer Simulation↗