Biomedical subjects
Publications and source records attributed to C Sohn.
The authors describe the histopathology of the resting cartilage and the growth plate in a case of diastrophic dysplasia and review the differential diagnosis with pseudo-diastrophic dysplasia and atelosteogenesis type II.
AIM: To compare the significance of the two-dimensional and three-dimensional sonography in the diagnosis of meniscal tears under clinical conditions. METHODS: Sixty menisci of knees with clinical symptoms (44 medial and 16 lateral menisci) were examined by an identical transducer in a two- and three-dimensional sonography technique. The findings were compared with the diagnosis made with subsequent arthroscopy. RESULTS: In the diagnosis of meniscal lesions the two- and three-dimensional sonography reached a sensitivity of 92% and 100% and a specificity of 83% and 88%, respectively. The positive predictive value of these methods was 58% and 67%. The negative predictive value was 98% and 100%. Because of the good results with the two-dimensional sonography, there were no statistically significant differences between both methods. The three-dimensional sonography, however, proved to be superior, to the two-dimensional sonography in the analysis of subgroups (medial and lateral menisci, menisci with and without clinical symptoms). The negative predictive value of the three-dimensional sonography was 100% for all of these subgroups. CONCLUSION: Although this study shows no significant difference in the results of two- and three-dimensional sonography, the analysis of subgroups displays a slightly improved significance for diagnosis of meniscal tears by three-dimensional sonography. The high negative predictive value shows that three-dimensional sonography, performed by an experienced examiner, may be useful to exclude meniscal tears. This result may help focus further cost-intensive or invasive examinations.
Routine prenatal ultrasound of a massively obese mother at 21 weeks of gestation revealed short-limb dwarfism in the fetus. The proportionate shortening of tubular bones of about 50 per cent of the normal length, the absence of thoracic dysplasia, and a normal head circumference narrowed the diagnosis down to a severe but non-lethal skeletal dysplasia. Ulnar deviation of the hands and talipes made diastrophic dysplasia the most likely differential diagnosis. At post-mortem clinical examination, the diagnosis of diastrophic dysplasia was clearly apparent due to highly specific 'hitch-hiker thumbs', similarly luxated big toes, facial dysmorphism, and a cleft palate. Retrospective re-evaluation of the prenatal ultrasound videos revealed the misplaced thumbs, which together with the ulnar deviation of the wrist and suspected talipes, led to the conclusion that the definitive diagnosis can be established prenatally, even in a mother with massive obesity.
BACKGROUND AND OBJECTIVES: Locally advanced breast cancers may form large, infected skin ulcers, which were traditionally treated with radiation therapy. Neoadjuvant chemotherapy is now standard treatment for locally advanced breast cancer. METHODS: The response of 33 patients with ulcerated breast cancer to primary chemotherapy was retrospectively analyzed. Antibiotics were not used in primary treatment. Tumor and ulcer responses were evaluated independently. RESULTS: Chemotherapy alone healed 18 of these ulcers. Neither responding nor refractory patients developed sepsis during this treatment. CONCLUSIONS: Chemotherapy is safe and effective treatment for patients with infected malignant breast ulcers and does not cause systemic sepsis.
There is no consensus regarding the clinical significance of conventional two-dimensional ultrasound in the diagnosis of meniscal tears of the knee. Three-dimensional ultrasound spatially reconstructs a transparent image of subsequent ultrasound scans. In an experimental study of 96 menisci, radial and oblique tears were detected more often by three-dimensional ultrasound. In a clinical study of 60 menisci the two- and three-dimensional ultrasound reached a sensitivity of 92% and 100%, a specificity of 83% and 88%, a positive predictive value of 58% and 67%, and a negative predictive value of 98% and 100%, respectively. Altogether, there was no statistically significant difference between both methods. The high negative predictive value, however, shows that the three-dimensional ultrasound may be a clinically relevant examination for special questions in the diagnostics of meniscal tears.
On the assumption that the architecture of blood vessels of malignant tumors, formed by neoangiogenesis, shows characteristics that are different from those of blood vessels of benign tumors or physiological findings, we have tried in the present study to investigate the behavior of these different vessels under increased blood pressure. Using a special stand, the same sonographic section could be stably maintained during an examination time of approx. 4 minutes. Using a new computer program, the color pixels of the employed Angio color technique were quantified and recorded as a function of the measured blood pressure. To increase blood pressure, the patient had to press a hand grip, which practically always caused a systolic blood pressure elevation of more than 15-20 mmHg. Seventy patients with sonographically detected breast tumors were examined; 54 (14 benign and 40 malignant tumors) could be included in the evaluation. We found four typical types of curves: Curve type 1 is associated with an instantaneous increase in blood flow with increased blood pressure, followed by a drop in the blood pressure, with a slow decrease in blood flow as the blood pressure drops (with 29 malignant and 3 benign tumors). Curve type 2 shows a continuous increase in blood flow-though somewhat delayed with respect to the rise in blood pressure-which is also observed when the blood pressure drops (exclusively benign tumors). In curve type 3, maximum blood flow is reached after the blood pressure maximum, and then the blood flow decreases (1 benign and 3 malignant tumors). Curve type 4 features decreased blood flow in spite of increased blood pressure (3 benign and 5 malignant tumors). The described quantification method, in combination with the stand, permits for the first time analysis of a tumor under increased blood pressure as to its blood flow behavior over time in an examination using a challenge test. Here one can find two distinctive curve types (types 1 and 2) that correlate mostly with malignant (type 1) or benign (type 2) breast tumors. Should this tendency be substantiated by additional large-scale studies, it would seem that a new ultrasonic possibility for differential diagnosis has been found.
BACKGROUND: The aim of this study was to find a possible relationship between the biological behavior of carcinomas of the breast and sonographically detectable blood flow after first studies showed a correlation between blood flow and prognostic factors. METHOD: 259 patients with ductal invasive breast cancer were examined using MEM (i.e., the Maximum Entropy Method), a new sonographic blood flow measurement technique capable of discerning considerably slower blood flow velocities than Doppler sonography. Due to the lack of objective methods for quantifying the blood flow, the findings were divided into three classes dependent upon the visual color information obtained. The blood flow was correlated with the size of the tumor, lymph node and receptor status, ploidy and S-phase fraction. RESULTS: Most of the patients with small tumors, without lymph node metastases, with positive receptors, with a diploid genome, and with a low S-phase fraction belonged to the group with the lowest blood flow. CONCLUSION: The close relationship between the established prognostic factors and the sonographic blood flow measurements using MEM might be indicative of a new preoperative prognostic factor; this must, however, be confirmed by larger studies.
BACKGROUND: Two new blood-flow-diagnosis techniques have recently been developed as supplements to the established color techniques: the MEM (maximum entropy method) technique and color flow amplitude (power Doppler). These are capable of representing blood flow in distinctly more slowly flowing areas than is possible with the conventional Doppler technique. METHODS: Both methods make use of the Doppler technique in part, yet analyze the reflected signal in a different manner, in so doing optimizing the relation between the noise and the signal. Measurements were obtained on two anatomic flow models to test the sensitivity of both techniques under slow flow conditions. RESULTS: The slowest flow the MEM technique was capable of recording was 0.5 mm/s, albeit utilizing a 5-MHz transducer for the MEM technique and a 10-MHz transducer for the angio technique. One may thus assume that the MEM technique would be still more sensitive when utilizing a 10-MHz transducer. The advantage of the MEM technique is its real-time flow representation: The angio technique requires a few seconds of acquisition time. This could have serious consequences during clinical utilization. Doppler sonography was merely capable of detecting a minimum flow velocity of 15 mm/s. The angio technique is less dependent on the angle during flow representation than the MEM technique. CONCLUSIONS: The distinctly higher sensitivity of these two new color techniques offers new possibilities in the clinical sector as far as the perfusion diagnosis of organs and tumors is concerned.
Agenesis of the cerebellar vermis (paleocerebellar agenesis) with fusion of the cerebellar hemispheres (rhombencephalosynapsis) is a rare malformation of the central nervous system (CNS). Its combination with synencephaly (telencephalosynapsis), telencephalic ventricular aplasia, aqueductal atresia and cystic fourth ventricle has not yet been described, as far as we know. Here, we report this combination in a 23-weeks' gestation male fetus who was aborted to a 24-year-old diabetic mother. In this fetus with cerebral and cerebellar hemispheric fusion, vermian agenesis was associated with a Dandy-Walker-like posterior fossa cyst, in spite of the fusion of the hypoplastic cerebellar hemispheres. The CNS malformations were further accompanied by dysmorphic facial stigmata such as unilateral atresia of the external ear, ocular hypertelorism and a broad nasal bridge. Preaxial polydactyly and contractures of the upper limbs were the only associated non-cranial abnormalities. Cytogenetic studies revealed a numerically and structurally normal male (46, XY). The malformation complex described in this fetus of a mother with antedating pregnancy diabetes appears to represent a previously undescribed aberrant syngenetic CNS phenotype, some basic teratogenetic aspects of which will be discussed in this paper.
In connection with umbilical cord punctures and transfusions the degree of pathology still tolerable after these procedures as well as the influence on subsequent obstetric management has to be discussed. In a prospective study we evaluated 98 cordocenteses with (n = 44) and without (n = 54) transfusion (25-37 week of gestation). 30-160 ml of blood were transfused. In all cases the umbilical vein was punctured at the point of insertion into the placenta (46x posterior and 52x anterior wall placenta). A CTG was performed prior and after the punction and was evaluated according to the Fischer score. After the procedure, the course of pregnancy was normal in all puncture patients and in 52 of 54 patients who also underwent a transfusion. Because of a pathological CTG due to a severely hydroptic fetus, a caesarean section had to be performed in one woman seven hours after umbilical cord transfusion. In another patient an emergency section was necessary immediately after the umbilical cord transfusion, due to persistent fetal bradycardia. In the puncture group mean Fischer score values decreased from 9.1 to 7.5, in the transfusion. In another patient an emergency section was necessary immediately after the umbilical cord transfusion, due to persistent fetal bradycardia. In the puncture group mean Fischer score values decreased from 9.1 to 7.5, in the transfusion group from 8.6 to 7.4. The results were more unfavorable when amplitude and occurrence of accelerations were considered, especially in the transfusion group. In one fifth of the puncture cases and one fourth of the transfusion patients the criterium of baseline crossings improved after the procedure. In summary, a pathological CTG is to be expected after umbilical cord punctures and transfusions, with however, only the necessity of surveillance. Only in cases of persistent fetal bradycardia an active obstetric management is indicated.
To establish the requirements for real-time transfer of an ultrasound examination via telecommunication network the following tests were performed: The ultrasound data were transferred from the video out of an ultrasound system to a basis terminal of the German Telekom. Simultaneously, an external video camera filmed the positioning and movements of the ultrasound transducer, and the verbal comments were recorded. These informations were transmitted to Karlsruhe and London, where they were rerouted to the examination room in Heidelberg. Here the informations were received on a Telecom reception unit/terminal and compared directly with the initial signal. The quality was sufficient if the moving ultrasound images and the camera image of the transducer as well as the oral comment were transmitted over 2 parallel ISDN lines. The delay to a real-time transmission of the examination process is only in the range of milliseconds. If only one ISDN line is used, the image quality is unsatisfactory, three parallel lines do not bring significant improvement of image quality. Telemedicine seems a new possibility to bring the knowledge of specialized centers to the practicing gynaecologists thus avoiding unnecessary referrals. Still unanswered, however, are the problem of liability, data protection and costs.
A two year retrospective study of 57 women with fetal hygroma colli between 2 and 15 mm was carried out at the University Women Hospital in Heidelberg. In this study maternal age, week of gestation, thickness of the nuchal oedema and the genetic results of amniocentesis were documented. Chromosomal abnormalities were found in 20 cases (35%), monosomy X in eleven, trisomy 21 in five and trisomy 18 in four. No connection between an individual syndrome and a particular week of gestation could be found. An increase of the thickness of the nuchal oedema showed a significant correlation to the incidence of aneuploidies. Chromosomal abnormalities were not observed in cases of less than 3 mm thickness (0/5). Between 3 and 4.9 mm one abnormal karyotype (4 mm) was found (1/18) whereas in the group of 5-6.9 mm approximately one third (6/15) of all fetuses showed chromosomal abnormalities. Aneuploid karyotypes were found in two thirds of cases (14/20) with a fetal nuchal translucency of 7 mm and more. Surprisingly, a correlation between maternal age and incidence of fetal chromosomal abnormality could be seen, but it was not significant. While a chromosomal aberration could be connected to age in 50% of mothers under the age of 25 and over 34, only a third of women aged 25-29 and only one fifth aged 30-34 showed chromosomal abnormalities in combination with hygroma colli. Our results confirm the recommendation of previous studies for extensive ultrasound examination during the first and second trimester in order to improve early detection of fetal chromosomal abnormalities particularly in women not normally covered by the age-related indication for amniocentesis.
Doppler sonography now has a definite place in the surveillance of risk pregnancies. Uniform clinical management is sometimes difficult especially in borderline cases. The following study demonstrates the possibility of standardizing and systematizing Doppler results using a score. In a collective of 253 pregnant women we performed Doppler examinations in the fetal aorta, umbilical artery, middle cerebral artery, internal carotid artery. The results were divided into 4 groups and correlated to the fetal outcome. There was a highly significant worsening in prognosis regarding duration of pregnancy, birth weight and rate of cesarean sections with increasing Doppler score. In the event of pathological and highly pathological scores, the average duration of pregnancy was 23 and 48 days shorter than normal. As a result, there was a highly significant reduction in the average birth weight compared to fetuses with normal Doppler scores: by 1060.7 g in the case of a pathological score and by 1633.5 g in the case of a highly pathological score. There was a highly significant correlation concerning the rate of cesarean sections and the indication "fetal distress". The average interval between diagnosis and birth was 6.3 days in the case of pathological Doppler findings and 2.3 days in the case of highly pathological findings. The difference was highly significant. In the case of highly pathological scores all fetuses were delivered after at least 5 days, compared with after at least more than 10 days in those with only pathological Doppler findings. This reflects the fact that there is none room for discretion in case of a highly pathological flow. In summary the Doppler score allows better estimation of fetal risk and can improve fetal prognosis by special monitoring and earlier obstetric intervention.
The association of increased maternal serum alpha-fetoprotein levels (MS-AFP) with certain morphologic anomalies of the fetus is fully established. These anomalies are abdominal wall defects (e.g. omphalocele, gastroschisis, complete eventration), neural tube defects (anencephalus, spina bifida, encepalocele) and other malformations (e.g. coccygeal teratoma). The present study compares MS-AFP levels with amniotic fluid alpha-fetoprotein (AF-AFP) and acetylcholinesterase activity, the results of ultrasound, genetic and morphologic examination. Between April 1992 and November 1995 60 patients were referred to our clinic for further diagnosis after detection of elevated MS-AFP. After an ultrasound examination was carried out amniocentesis (AC) was performed in 54 cases, AC + placentesis (PC) in 3 patients and PC only in 3 cases with anhydramnion. Mean maternal age was 29 years (range 20-37 years). Punction was performed at a median of 19 + 1 weeks of gestation (15 + 2-23 + 2 weeks of gestation). MS-AFP, AF-AFP and acetylcholinesterase activity was measured. MS-AFP and AF-AFP were given as multiples of the median (MoM). Values < or = 1-2.0 MoM were considered normal. Elevated levels were defined to be greater than 2 MoM. In all cases the chromosomal finding was normal or norm variant. Sonographical anomalies were detected in 7 fetuses (3 cases with spina bifida, 1 case with omphalocele and 3 cases with abdominal wall defects in connection with other malformations). All sonographic diagnoses were confirmed post partum. The MS-AFP varied between 0.9-6.0 MoM. In 7 cases MS-AFP previously (referring center) evaluated as increased was found to be within normal range in our department. This cases included normal values were found in 30 cases and 25 findings were pathological. 2 out of 7 structurally abnormal fetuses had normal values, 5 of them had elevated MS-AFP. In the group of normal fetuses the highest MS-AFP we found was 6.6 MoM. In the AC-group the AF-AFP ranged between 0.7-8.7 MoM, it was within normal range in 50 and pathological in 8 cases. In the group of fetuses without structural anomalies the highest AF-AFP was 7.5 MoM. In the group of fetuses with structural anomalies the AF-AFP values were 1x normal and 3x pathological (> 3.5 MoM). Acetylcholinesterase activity in the amniotic fluid was negative in 51 cases, positive in 4 cases and faint positive in 2 cases. In all fetuses with structural anomalies in which an AC could be performed, acetylcholinesterase activity was positive. On the other hand we found only 1 of the structurally normal fetuses with positive acetylcholinesterase activity. Elevated MS-AFP and AF-AFP may be an indicator for morphological anomalies. Yet there were many positive results without any sonographical findings. The determination of a positive acetylcholinesterase activity in the amniotic fluid is more specific. All malformations have been detected by ultrasound examination before the results of the AF-AFP were available.
AIM: The sensitivity of the two procedures for slow blood flow velocities in two flow phantoms examined and compared to conventional colour Doppler. METHOD: In two phantoms with vessels between 0.3 and 6 mm diameter the slowest measurable blood flow with the different techniques was determined. The influence of various application angles was also studied. RESULTS: The slowest blood flow velocity detected with the MEM technique was 0.6 mm/s and with the angio-technique 0.4 mm/s. Two different scan-heads were used; a 5 MHz probe for the MEM procedures and a 10 MHz probe for ultrasound angiography. Using a 10 MHz scan-head will most likely lead to increased sensitivity of MEM. Blood flow representation with the MEM technique is real-time, while several seconds of acquisition time are required for the angio-technique, which is a disadvantage during clinical use. Conventional Doppler was merely able to represent 15 mm/s blood flow. The angio-technique was less dependent on the application angle than the MEM procedure. CONCLUSION: The definitely increased sensitivity of the two colour methods open up new areas in the diagnosis of organ and tumour perfusion.
AIM: The clinical value of two-dimensional ultrasound in examining the menisci of the knee compared to other methods is controversial. We studied the utility diagnosed by three-dimensional sonography in evaluating meniscal tears. METHOD: 96 menisci with standardised artificial lesions were examined in a bath of Ringer solution. Two-dimensional ultrasound was compared to three-dimensional ultrasound, which creates three-dimensional reconstruction of sequential ultrasonographic images. RESULTS: The three-dimensional ultrasound had a higher sensitivity of 88% vs 69% with a specificity of 83% vs 94% for the diagnosis of meniscal tears compared with the two-dimensional method. The sensitivity in imaging was 54% in each case for longitudinal tears, 63% vs 96% for horizontal tears, 67% vs 37% for oblique tears and 54% vs 0% for radial tears. The difference of these results, however, was not statistically significant. Radial tears were more frequently diagnosed by three-dimensional sonography. CONCLUSION: In our model, sonographic diagnosis of meniscal tears was improved only partially by using three-dimensional ultrasound. Whether in vivo other factors alter the minimal differences between the two techniques is the subject of ongoing investigation.
Doppler sonography now has many indications in obstetrical diagnosis. Its wide and often uncritical application was the reason for our study group to confirm its importance. Moreover, we wanted to prove our own procedure. We made 950 Doppler examinations in a group of 449 pregnant women and correlated the results to the fetal outcome. Children with pathological Doppler findings showed a significantly lower birth weight of 599 g, a significantly lower duration of pregnancy of 6 days, a significantly higher rate of Caesarean sections and a significantly higher death rate compared to children with normal Doppler findings. Concerning Apgar- and pH-values there was not any significant difference between the two collectives. These results show that fetuses with pathological Doppler values or growth retardation can have the same prognosis as fetuses with normal Doppler findings if they are recognized and monitored at an early stage. The morbidity by acidosis can thus be reduced.
Sonographic examinations of the female mammary gland within the frameworks of the diagnosis of breast cancer playa fundamental role in the early detection of benign and, in particular, of malignant growths. Sonographic blood flow determinations can be used as an auxiliary noninvasive examination method. This is based on the fact that malignomas differ from benign tumors in that they display a pathological increase in vascular-ization. These changes of the circulatory conditions can be utilized in the diagnosis of the dignity of breast cancer.