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Biomedical subjects

C Sohn

Publications and source records attributed to C Sohn.

At least 73 records · Page 4Linked to original sources
PubMed1994

[The positive "vocal fremitus" in malignant breast tumors in color MEM ultrasound imaging--an exciting artifact in confirming the diagnosis?].

In the experimental phase of application of a new Non-Doppler technology (MEM system, Acoustic Imaging, Phoenix; Dornier Medizintechnik) we observed, that in patients, who spoke during colour imaging of a breast tumour, artifacts appeared in or around the lesion: the colour artifacts were seen regularly inside the tumour in cases of malignancies, and exactly surrounding benign tumours. Postoperative histological findings served as an objective criterion of classification/differentiation. To examine this phenomenon, we performed a study in 71 patients. These women with a sonographically detectable tumour (37 malignant, 34 benign) were examined on the day before surgery. We observed, that if patients uttered the number "99" with a relatively low voice or alternatively hummed a deep sound, the artifacts could be regularly visualized. In 66/71 patients (93%) status evaluation by artifact generation due to vocal fremitus examination was correct. In 3 patients the tumour was erroneously described as malignant, histology showing a proliferative mastopathy. In 2 cases the tumour was classified as benign, whereas histology revealed a malignancy, in both patients a large ductal-invasive carcinoma (> 3 cm). This phenomena could, however, not be reproduced with other colour techniques. A possible explanation is: Thoracic vibrations during speech can be registered by the MEM technique. These vibrations are not perpetuated into the benign lesion characterised by a displacing growth, due to which the vibrations are "barred off" at the borders of the tumour. Infiltrating growth typical of a malignancy causes transmission of these vibrations into the center of the tumour.(ABSTRACT TRUNCATED AT 250 WORDS)

Artifacts↗
PubMed1994

[Development of Doppler parameters in fetal and maternal blood vessels 10 days before to 10 days after the calculated due date].

Doppler sonography can help to assess a foetal risk situation prospectively. This procedure is therefore well suited for the screening of risk pregnancies in the 3rd trimenon. The role of Doppler ultrasound at delivery is still controversial, since, on the one hand, no data on the behaviour of Doppler parameters directly at the onset of delivery are available, and on the other hand the obstetric consequences from pathological findings are not clear. For this reason, we observed 45 normal pregnancies from the 10th day prior to the date of confinement till the 10th day post partum. In 20 patients we registered Doppler parameters from 4 days before until the onset of true labour. In all these cases, a reduction of the end-diastolic blood flow in the foetal aorta was found, which became evident by the increase of the resistance index to pathological values. Concomitant decrease of the resistance index in the foetal carotid artery was typical for a circulatory system. Since foetal outcome was normal in all newborn, this change in Doppler parameters directly at the beginning of labour must be considered as physiological. The findings suggest a physiological placental insufficiency. Since however, parameters in the uterine vessels did not show any changes, the insufficiency has its probable origin in the placenta. From these findings, one might speculate, that the supply deficiency is the labour inducing factor. No clinical consequence can thus result from pathological Doppler data found in patients directly prior and after delivery. Cardiotocographic screening is necessary.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1994

[Diagnosis of the breast tumor entity with "vocal fremitus" in ultrasound diagnosis].

In the published study a totally new method for the diagnosis of malign and benign tumors of the female breast is presented. During sonographic examinations with the maximum entropy method we found out, purely by chance, that artifacts produced by vibrations of the thorax can be used to differentiate malignant from benign lesions. These artifacts in form of small colour pixels can be provoked by the vocal fremitus of the internal medicine or by humming a deep sound. In case of malignancy, the colour artifacts are visible inside of the tumor, in benign lesions, however, only in the surrounding tissue. On the preoperative day, 95 patients were examined with the method described above. In 91% of the cases the diagnosis of the dignity corresponded with the histological results. Seven times a benign lesion was classified as a malignant tumor and twice malignancy was not correctly diagnosed. Our explanation of these phenomena is the following: Benign lesions of the female breast show a displacing growth and a definable boundary. Thus the vibrations are damped and not conducted into the tumor. In contrast, malignant lesions grow invasively into the surrounding tissue. Consequently, the vibrations can be conducted into the center of the tumor by this dissemination.

Adenocarcinoma↗
PubMed1994

[The advantages of spatial, three-dimensional ultrasound imaging in clinical application].

Following the first three-dimensional (3D) ultrasound imaging of organs using 3D ringstructures, which we developed in 1986, the method had to be improved and refined because of sources of error resulting from the ring structure. The newly developed 3D method enades its application in clinical routine. By rotating the sectional plane around a horizontal axis using an especially constructed 3D probe, in 5 s 60 ultrasound sections of the examined tissue are registered. These 60 sections are calculated transparently and than compiled into a transparent spatially reconstructed image. In spite of the enormous information, the 3D picture is projected on the screen after a very short time. There is no loss in information. The spatially reconstructed body can be cut along any imaginable plane so that planes can be demonstrated which normally are inaccessible to conventional sonography. This new method presents possibilities which were formerly confined to CT and MRI. We tested this method mainly in prenatal and tumor diagnoses. It has been shown that the dignity of tumors can be differentiated in many cases already by means of the 3D-image. An indistinct image is characteristic for a malign tumor, and a sharply defined image represents a benign lesion. The diagnosis of fetal malformations can profit from this new method. Exact localizations and volume determinations are now sonographically possible. New diagnostic possibilities by means of ultrasound are forthcoming. But this needs further technical investigations. Both the presentation with a closed surface and the transparent presentation will have indications in the future. Our goal is a free applicability of the probe.

Breast Neoplasms↗
PubMed1994

[Fetal enlarged flaccid intestinal loops and pathologic Doppler findings--criteria for fetal distress].

In pregnancies with signs of placental insufficiency relatively often flaccid and enlarged intestinal convolutions were detected, which differed markedly from hyperperistaltically distended convolutions as in the case of bowel obstructions. In order to show a correlation between placental insufficiency i.e. a deficiency in supply--and the typical flaccid bowels, we performed a prospective study on 258 pregnant women with placental insufficiency and a control group of 151 normal pregnancies. The examinations were performed with a color duplex system. As criterium we registered detection of flaccid bowel convolutions-characterized by rich echoes-which could be well distinguished from the bowel which appears as homogeneous. It could also be well differentiated from the mostly echo-free aspect of obstructed bowels, associated by hyperperistaltics. Flaccid and enlarged bowel convolutions were found in 67 patients in the collective with placental insufficiency (26%) and in 8 patients in the control group (5%). In all fetuses the aorta as well as the carotic artery were examined by Doppler sonography. In the group with placental insufficiency markedly increased values were noted from the resistance index (RI) in the aorta as compared to the controls. The values in the carotis, however, were lower. This must be considered as a sign for a higher degree of centralization in these fetuses with supply deficiency. In those fetuses with enlarged bowel convolutions the doppler parameters were even more pathologic. Their post partal condition was also clearly worse. In 28 fetuses of this group in almost all cases no diastolic flow could be detected in the arteria mesenterica superior, whereas such a flow was found in all other cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1993

Poor survival of black patients in carcinoma of the endometrium.

PURPOSE: To compare the prognostic factors and survivals of black and white patients with endometrial carcinoma. METHODS AND MATERIALS: A retrospective study was undertaken of a total of 290 patients with endometrial carcinoma who were treated similarly at the Health Science Center at Brooklyn and Kings County Hospital Center from 1975 and 1990. One hundred and thirty-six of 290 (47.2%) were black and 135/290 (46.9%) were white. Well-known prognostic factors affecting endometrial carcinoma were studied in black and white group of patients. Their overall survival and comparison of survival in each prognostic group were also estimated using multi-variate analysis. RESULTS: Fifty-four percent of white patients had Stage I disease, compared to 45.9% in black patients. In Stage II, 51.6% were white and 48.4% were black, and in Stage III, 88.89% were black and 11.1% were white patients (p = 0.034). Fifty six percent Grade 1 patients were white and 44% were black. In Grade 2, 53.3% were white and 46.7% were black and in Grade 3 disease, 70.5% were black and 29.5% were white (p = 0.008). Up to the inner third of myometrial invasion had occurred in 60.6% of white patients and 39.4% in black patients. The middle third of the myometrium was invaded in 60.7% of white patients, and 39.3% of black patients. Thirty-seven percent of outer third of myometrial invasion was found in white patients and 63% in black patients (p = 0.038). Seventy-two percent of positive lymph nodes were found in black patients and 28.0% in white patients (p = 0.01). Sixty-one percent of patients with positive peritoneal cytology were black as compared to 38.7% in white patients (p = 0.017). The overall ten-year corrected survival for white and black patients was 72% and 40%, respectively (p = 0.0003). Survivals comparisons, when stratified by race and each prognostic group, showed statistically significant overall survival differences in favor of white patients. CONCLUSION: Black patients with endometrial carcinoma have poor survival. Low socio-economic status (SES) would not explain these findings. More research is required to determine the cause of poor survival in black patients with endometrial carcinoma.

Adult↗
PubMed1993

Endometrial carcinoma. Influence of prognostic factors on radiation management.

The earliest intracavitary radium treatment for uterine cancer was reported in 1908. Refinements reported during the next 20 years, using an intrauterine tube and colpostats or radium capsules, established a treatment philosophy of preoperatively irradiating uterine and parauterine tissues. Thus, preoperative intracavitary irradiation became entrenched as therapy for all endometrial cancers for the better part of four decades. In the 1950s and 1960s, the ability of external irradiation to eradicate cancer in regional lymphatic vessels prompted the use of pelvic field irradiation in Stage II and III and recurrent disease. The results of surgical exploratory studies in the 1970s established more refined criteria for preoperative or postoperative external pelvic irradiation in high-grade infiltrating Stage I cancers. In the 1980s, it became apparent that, for tumors with lymphovascular invasion, clear cell, and serous papillary histologic types, the disease spread to the upper abdomen and the paraaortic nodes might benefit from extended field and/or whole abdominal irradiation, with or without systemic bolus or concomitant continuous-infusion chemotherapy. In the 1980s, a subset of patients was identified with high-grade lymphovascular invasion clear cell and papillary serous histologic types or with positive peritoneal cytologic findings who were at high risk of failing in the paraaortic nodes and/or the upper abdomen for whom extended field or whole abdominal irradiation have been advocated. Given the fraction and dose limitation for a large abdominal field, the addition of systemic concomitant bolus or continuous infusion of chemotherapy currently is proposed to improve the control of intraabdominal failure in these high-risk patients.

Combined Modality Therapy↗
PubMed1993

[Blood supply of malignant and benign tumors of the internal genitals].

Malignant tumours differ mostly from benign lesions in their blood supply. This fact can be used in the sonographic diagnosis of the tumour status. This, however, depends on the availability of ultrasound equipment, capable of demonstrating this difference, which can only be detected in smallest blood vessels, in which the blood flow is extremely slow. We employed the Sonolayer SSH 140A (Toshiba, Japan) and the Quantum 2000 (Siemens, Germany) for diagnosis of lesions of the female inner genital tract. Both instruments could visualize the slow blood flow velocities in the tissues examined. Diagnosis of blood circulation in tumours of the inner genital tract thus seems less dependent on the technology employed as is the case in examining the breasts. 41 patients with ovarian tumours, 31 with endometrial pathology, and 33 with cervical lesions were examined preoperatively. Findings were correlated to histology. The lowest resistance index (RI) measured was evaluated. The following RI values were found: Ovarian tumours: malignant 46%, benign 78% (49%). Tumours of the corpus uteri: malignant 54%, benign 65% (55%). Cervical lesions: malignant 55%, benign 79% (58%). Results in premenopausal women with non-malignant lesions are specified in brackets. Pre- and postmenopausal status proved essential. When compared to breast findings, the difference between benign and malignant tumours of the inner genital tract is less pronounced due to the fact, that, physiologically, these tissues are characterised by a higher blood supply. Differentiation was thus almost impossible in premenopausal women. However, in menopausal patients, a highly significant difference between benign and malignant tumours was found, which could serve as basis for tumour status prognosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Blood Flow Velocity↗
PubMed1993

[Ultrasound--future developments].

During the last years, rapid technical evolution has led to the development of transducers with extremely high resolution (generating two-dimensional (2D) sectional scans not mere spacial cuts), thus creating the preconditions for spacial 3D reconstruction from a series of 2D sectional scans. For the 3D technique a transducer is required that can register a multitude of sectional scans of the organ examined. This series can only be reconstructed according to the actual spacial situation by a computer. Transparent calculation of the individual section diaphanous scans results in a 3D image of the organ. The new method presents the advantage of less subjectivity, since the 3D image is not merely created in the mind of the examining specialist, but is reconstructed by the computer. Moreover, the computer image can be disassembled into the original and even sonographically unattainable section scans, thus furnishing additional information. Objective and exact volume calculations, localization and control of the progress of a disease becomes feasible. Further progress in gynecologic ultrasound has been achieved by technical improvement resulting in the applicability of intraluminal sonography for gynecologic indications as well. Due to newly developed microtransducers, the advantages of intraluminal ultrasound, used mainly in angiology up to the present, can now be used for the representation and functional diagnosis of the fallopian tube as well. Some technical problems have, however, yet to be solved. By utilizing a computer-aided evaluation system, ultrasound information, not realized by the human eye, can be represented.(ABSTRACT TRUNCATED AT 250 WORDS)

Equipment Design↗
PubMed1993

[The value of Doppler imaging of the aorta, carotid artery and middle cerebral artery in obstetric diagnostics].

The relation of blood blow in the fetal aorta and carotis is a marker for the well being of the unborn child. Increase of cerebral vascularity associated with decrease of blood flow in the aorta is a sign for a fetal risk situation. It is, however, of disadvantage that the fetal carotis is often difficult to image with an wedge-shaped angle between doppler beam and vessel. We therefore included screening of an intracerebral vessel (a. cerebri media) in order to find out whether examination of this vessel, much more easier to perform, may have a similar diagnostic value or be an even more sensitive prognosticator of fetal risk than the carotis. In two hundred and forty patients in the 29th to 40th week of gestation all these three vessels were scanned with the duplex system AI 3200, Dornier company, Germany. The result was correlated to sonographic biometry, birth weight, and mode of delivery. It could be proven that when analyzing individual findings, pathology in the risk groups is much higher, whereas mean values showed less marked differences between risk and control groups. Our results suggest that the a. cerebri media is a slightly more sensitive indicator of fetal risk, since in this vessel retrograde resistance can be detected earlier and is more evident. A combination between assessment of the aorta and a cerebral vessel, is however, the method of choice in cases of pathological findings in diagnosis of fetal well being, since only examination of a peripheral and a central vessel results in an exact diagnosis.(ABSTRACT TRUNCATED AT 250 WORDS)

Aorta↗
PubMed1993

[Effect of intracavitary irradiation on the venous system of the pelvis and leg].

A late complication of combined radiotherapy for malignoma of the inner genital tract is leg edema, whether of venous or lymphatic origin, which is not always clear. To analyse the influence of radiotherapy upon the pelvic and leg venous system, we performed sonographic caliber, occlusion plethysmographic and light reflexion rheographic measurements of veins in 32 patients prior and subsequent to irradiation. No statistically significant difference was found between mean values measured with the different methods. A clear deterioration of venous function was detected after treatment. Sonographic examinations of pelvic vessels after radiotherapy showed veins much less clearly outlined and with thicker walls, thus pointing to a direct connection between irradiation and edema of the vein wall. Whereas deterioration of the other parameters may also be explained by, for example, long periods of lying. Since according to our own observations, an insufficiency of the leg venous valves occurs relatively often, sometimes even years later, there is a clear correlation between irradiation and edema of the venous wall, with a slight deterioration of venous function detectable directly after irradiation. In order to prevent vein damage, prophylaxis of thrombosis and vessel topography should therefore always be considered when planning radiotherapy.

Adult↗
PubMed1992

Ultrasound scanning for the diagnosis of meniscal lesions of the knee joint.

We report on the efficacy of ultrasound scanning as a noninvasive method of the preoperative diagnosis of meniscal lesions of the knee joint, using the 7.5-Hz head of a real-time scanner. In studies on cadaveric knee joints we found a high efficacy in diagnosing meniscal lesions using ultrasound. Comparative clinical studies on 51 patients who had undergone preoperative ultrasound scanning showed a strong correlation of ultrasound diagnosis with intraoperative findings. Arthrography was performed in 24 of the 51 patients, yet ultrasound studies proved to be more effective than arthrography in diagnosing meniscal lesions. Consequently, we believe that ultrasonic scanning as a noninvasive method of diagnosis is more helpful in identifying meniscal lesions of the knee joint.

Arthrography↗
PubMed1992

[Initial results of a new method of sonographic diagnosis of lung maturity].

The immaturity of the foetal lung is one of the central problems in obstetrics. In this paper first results are presented to determine the maturity of the foetal lung by sonography. Using the foetal liver as a reference organ we are avoiding the known pitfalls which made it impossible in the past to standardise the foetal lung changes depending upon the age of gestation. We examined 121 patients between week 27 and week 41. In one ultrasound section cut we depicted lung and liver as well. According to the known A-mode we registered frequencies in both organs. The registered frequencies were entered digitally into a computer and checked for f mean, f max and f min. Subsequently we calculated quotients of frequencies of the foetal lung and liver. For all weeks of gestation the mean value and standard deviation were calculated. We found that the liver is an adequate reference organ, since there is no change in the reflection pattern between the different weeks of gestation. We registered significant differences in the quotients of lung and liver between the different weeks of gestation, a cutting line being week 35. A quotient of Q mean lower than 1.1 hints to lung maturity while values over 1.1 point to immaturity.

Female↗
PubMed1992

[Ultrasound diagnosis of blood flow in benign and malignant breast tumors].

Malignant tumours can be differentiated from the benign ones by their vascular blood supply. We employed three methods to analyse the blood flow: the angiodynograph, the duplex system, and the continuous-wave Doppler method, and measured the blood flow in 151 patients on the preoperative day. Histology revealed a malignoma in 92 cases and a benign tumour in 59 cases. It was found, that in more than 90% of the malignomas, a high blood flow was identified in or around the tumour by means of the colour method (angiodynography), which could be quantified by the pulsed-wave Doppler. A significantly lower blood flow was evident in the benign tumours with a markedly increased resistance index (by 80%) established by means of the pulsed-wave Doppler. Continuous-wave (CW) Doppler showed a significantly higher blood flow with almost all malignomas in the entire breast, than was the case with benign changes. Our studies showed, that the enhanced blood flow in and around malignant tumours can be visualised by means of update technology, angiodynography being particularly suitable for demonstrating the flow by the B-mode. Quantification, however, is, at present, only possible by employing the duplex method with pulsed-wave Doppler. CW Doppler is suitable only for blood flow diagnosis of the entire organ, but it requires great precision of working method and is time consuming; tumour blood flow cannot be visualised on-target by this method.

Blood Flow Velocity↗
PubMed1992

[Palliative laser therapy in gynecologic oncology].

Local recurrences of carcinomas of the breast and genitals are a severe psychic and physical strain on the patients. Continuous confrontation with an often visible and generally painful tumour manifestation is an indication for palliative treatment, if other oncological therapies can no longer be employed. In these cases, the possibility of laser use represents a new therapeutic approach. In a pilot study at the University of Heidelberg, Department of Obstetrics and Gynaecology, a palliative laser therapy was performed on 45 patients with locally recurrent carcinomas of the breast (n = 29) and genitals (n = 16). Carbon dioxide and Nd:YAG lasers were utilized for tumour resection, vaporisation and coagulation. This new concept, the combined application of both wavelengths has been proved to be most efficient.

Adult↗