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H Fendel

Publications and source records attributed to H Fendel.

106 records · Page 6Linked to original sources
PubMedDate not supplied

[Improved diagnosis of extrauterine pregnancy by endosonography].

Between July 1987 and January 1988, 44 patients with a tentative diagnosis of ectopic pregnancy underwent sonographic examination by means of vaginal probe at the Department of Gynecology and Obstetrics of the RWTH Aachen. The sonographic findings, all of which were confirmed by subsequent clinical and or surgical clarification, were as follows: an ectopic pregnancy was diganosed in 16 cases, an early intrauterine pregnancy in seven, an intrauterine abortion in seven, and in one case a uterine malformation-a dermoid cyst and a functional cyst. In 11 cases sonographic examination showed the interior genital region to be normal, with no sign of pregnancy. In the 16 ectopic pregnancies diagnosed, it was possible in 13 cases to visualize the pregnancy directly by sonography, including the amniotic sac, and to make measurements. In one case a normally developed ectopic pregnancy with living embryo was seen at the end of the seventh week of gestation post menstruationem. In the remaining three cases the diagnosis was established on the basis of an empty cavum uteri associated with a slightly enlarged uterus and demonstration of fluid in the pouch of Douglas. In two cases the ectopic pregnancy was correctly localized by "feeling" with the intravaginal probe to establish the cause of circumscribed pain. In three case the tentative diagnosis of an ectopic pregnancy made on the basis of sonographic findings was not confirmed by subsequent clarification procedures. The results described show that in most cases ectopic pregnancies can be demonstrated directly by sonography using an intravaginal probe.(ABSTRACT TRUNCATED AT 250 WORDS)

Diagnosis, Differential↗
PubMedDate not supplied

[Ultrasound echographic imaging and measurement of the amniotic cavity and yolk sac in early pregnancy: comparative study of intact and disordered pregnancies].

The chorionic cavity, vertex-breech length, yolk sac, and amnion were systematically demonstrated and measured in 50 early pregnancies, i.e., between the end of the sixth and the tenth week of gestation post menstruationem (p.m.). This was done in 23 cases with clinically and sonographically intact pregnancies without symptoms of abortion, in 12 cases with living embryos with symptoms of abortion, and in 15 cases of retained miscarriage. The thin amniotic membrane is sonographically demonstrated as a narrow, sharply defined reflected band in the chorionic cavity. In addition to direct demonstration of the amniotic membrane, the amniotic cavity can be demonstrated by a density difference in the echogenicity of the chorionic and amniotic fluids. While there are delicate, homogenously distributed inner echoes in the chorionic cavity, the amniotic cavity is empty save for the embryo structure. Sonographically, therefore, the amniotic cavity stands out as a spherical structure within the chorionic cavity. In all pregnancies with a living embryo it was possible to demonstrate the yolk sac sonographically as a sharply defined ring structure in the chorionic cavity. In 10 of the 15 cases of retained miscarriage only a rudimentary remnant of the yolk sac could be detected. The development of the amniotic and chorionic cavities and vertex-breech length was constant in the pregnancies with living embryos, the amnion developing synchronously with the vertex-breech length.(ABSTRACT TRUNCATED AT 250 WORDS)

Amnion↗
PubMedDate not supplied

[Ultrasonic diagnosis of congenital uterine abnormalities].

1-2% of women has abnormal uterine development due to nonunification of the Müllerian ducts in the embryonal period. At the RWTH Aachen, in the department of gynaecology and obstetrics, between January and June 1987, we had searched systematically for maldevelopment of the uterus in 2299 echosonografies. In 13 cases we found maldevelopment of internal genital; 5 of these cases were diagnosed by an echosonografic routine-examination. The echografic criteria of the different grades of uterine malformations have been determined, systematized and discussed in relation to the symptoms. The most frequent malformations as uterus subseptus, uterus septus, uterus bicornis and uterus duplex are subject of a detailed discussion. This work demonstrates that echosonografic is a very efficient instrument to diagnose uterine malformations and gives us a very exact anatomic interpretation of malformations.

Abortion, Incomplete↗
PubMedDate not supplied

[Involution-induced changes in arterial uterine blood flow].

The change of resistance in the uterine arteries was studied in 20 patients showing a normal involution on five consecutive days. A uterine artery was examined by Doppler sonography, the Doppler profile evaluated, and the quotient, Fmean, resistance index, and pulsatility index were calculated from the systole and diastole. These parameters, which provided information on vascular resistance independently of the angle between the Doppler beam and the vessel, indicated a continuous increase during the puerperium; the differences in values for different days were significant. The changes in the Doppler profiles in the puerperial period pointed to an increasing vascular resistance. In one-half of the patients this was shown only by an increasing slope to the systolic peak, a sharp drop to early diastole, and a clear distinction between systole and diastole. In the other half of the patients the Doppler curves were like those found in pregnant patients with EPH gestosis. This indicated that the pathologic mechanisms leading to increased resistance in the uterine vessels were the same in both groups. One cause of this may be contraction and compression of the blood vessels, the other, and probably principal, cause was reduction of the vascular system due to histolysis, as in the puerperium, or insufficient development of the vascular system, as in EPH gestosis. That is to say, functional and morphological changes occur in both cases. No decrease in resistance in the uterine vascular bed was detected in cases of puerperial subinvolution of the uterus.

Adult↗
PubMedDate not supplied

[Initial studies of 3-dimensional imaging using ultrasound].

In the study reported here three-dimensional sonographic imaging of organs was achieved for the first time. To make this possible it was first necessary to ensure, by appropriate guidance of the probe, that the sequence of sonographic sections was coordinated in their spatial arrangement. This was accomplished by constructing a probe guide with which parallel sonographic sections could be demonstrated. The distance between these sections was known, so that with the aid of suitable computer programs three-dimensional reconstruction of a kidney examined in a water bath was possible. Since, however, due to the uneven surface of the body, it will hardly be possible to obtain parallel sonographic sections of an organ, a new solution had to be found to ensure the necessary coordinated sequence of sections. The solution lay in rotating the probe. A further device was constructed in which the probe could be rotated farther, by known angles, from section to section. The pivotal point was at the center of the probe tip. The computer knew the angular distance between these sections and reconstruction to a three-dimensional image was therefore possible. Prior the three-dimensional reconstruction the ultrasonographic sections had to be contoured, since only the surface of the organ was available for three-dimensional image construction. Three-dimensional imaging of an organ can be achieved on the one hand by binary representation and on the other with a continuous organ surface. The advantage of binary representation is that the original sonographic data are incorporated in the image-producing process without any computer manipulation; with a continuous surface the distance between the individual sections has to be interpolated.(ABSTRACT TRUNCATED AT 250 WORDS)

Computer Simulation↗
PubMedDate not supplied

[Changes in uterine circulation in relation to body position in pregnancy].

The present paper reports on studies to determine the influence of body position on uterine blood flow. In ten pregnant patients (around the 35th week of gestation), over 700 measurements of systolic/diastolic action in the uterine vessels were made by Doppler sonography with the patients in various positions: lying down, standing, and sitting on the couch and the balance-variable chair; from the relationship between the systolic and diastolic levels conclusions were then drawn about the uterine blood flow in various body positions. It was found that it was best when the patient was lying down or sitting on the special chair without angling the hips; in contrast, diastole was lower in relation to systole with the patient standing and sitting on the examination couch. This means an increase in resistance or a reduction in blood flow. It appears reasonable to conclude that sitting on the balance-variable chair can be recommended to pregnant patients with signs of deficient fetal blood supply, in addition to bedrest, which is customarily advised. Apart from this, it is wise to use Doppler sonography to establish the body position in which uterine blood flow is best.

Blood Flow Velocity↗
PubMedDate not supplied

[Fetal functional atrioventricular blocks in pregnancies at risk].

Because antepartal and subpartal CTG monitoring is now widespread, fetal cardiac arrhythmias are being diagnosed ever more frequently. In a high-risk group of 148 pregnancies with placental insufficiency and preterm births, 14 CTGs manifested a rigid rectangular pattern, with alternating normal-frequency and slightly bradycardial cycles. The change in frequency occurred suddenly. All the children of the high-risk group were delivered by cesarean section and weighed less than 2500 g at birth. There is no description in the literature of similar CTG curves with sligthly bradycardial phases. However, there are some descriptions of cases of fetal AV blocks with severe bradycardias. These frequently occur in combination with fetal cardiac abnormalities and collagenoses of the mother. In the present authors' group these underlying conditions were not diagnosed. The fixed numerical ratio of the output frequency to slight bradycardia in the CTGs described here supports the tentative diagnosis of an atrioventricular conduction disorder, with relatively high conduction from the atrium to the ventricle. Since the arrhythmias did not continue in the newborns post partum it may be assumed that they were functional events. Birthweight, Apgar score, and the placental weight of the 14 births with the rectangular CTG curve described were lower than in the control group, i.e., the other 134 births. The CTG patterns described appear to have been caused by a chronic supply deficiency, resulting in functional AV conduction disorders. This CTG course should therefore be reason enough for intensive fetal monitoring.

Acid-Base Equilibrium↗
PubMedDate not supplied

[Diagnosis of fetal malformations with ultrasound--state of development].

Ultrasonography is of great importance for the prenatal diagnosis of fetal malformations and abnormalities. An early diagnosis in the second trimester is of great interest for an intrauterine or an extrauterine therapy planning (the choice of the time and mode of delivery). Defects of the neural tube including hydrocephalus, malformations of the extremities, the gastrointestinal tract, omphaloceles, the urogenital and cardiac system are described. Four cases of fetal malformations are presented: fetal myelomeningocele, hydrocephalus, bilateral hydronephrosis and lymphangioma with fetal ascites.

Anencephaly↗
PubMedDate not supplied

[Changes in the intensity of ultrasound echography in the fetal lung in the last trimester as a possible indication of lung maturity].

The maturation of the fetal lungs that is to say the adequate production of surfactant in the fetal alveoles as it is well known, reaches to its end about the 35.-36.th week of gestation. That can be proved by the measurement of the phospholipides in the amniotic fluid L/S ratio (Gluck). In order to find signs of lung maturity by ultrasound we studied fetuses between 25-42th week of gestation. Using an oblique coronal longitudinal scan through the fetal thorax and abdomen the right hemidiaphragm and subjacent liver could be seen. With increasing fetal maturity (32.-35.th week of gestation) lung reflectivity became greater than liver reflectivity at equivalent parts of the ultrasonic beam. After the 36th week of gestation, lung reflectivity was nearly always greater than liver reflectivity as possible sign of fetal lung maturity.

Female↗
PubMedDate not supplied

[Doppler studies of arterial blood flow in the uterus during labor].

By the pulsed doppler method the arterial uterine blood velocity was studied in 19 patients with contractions before and during labour. It is shown, that uterine contractions reduce blood velocity significantly. Normally there is a low resistance in uterine arteries, so that the diastolic flow is nearly as high as the systolic flow. In uterine contractions the vascular resistance increases. Systolic flow is reduced slightly and diastolic flow severely or completely. But a complete zero-flow couldn't observed in any studied uterine contraction.

Arteries↗
PubMedDate not supplied

[Determination of gestational age using crown-rump length and the biparietal diameter in the 1st half of pregnancy--comparison of 2 methods].

In the first half of pregnancy ultrasound investigations was made on women with known gestational age by regular menstruation or conception. In 221 cases of single pregnancies fetal crownrump length was measured. Biparietal cephalometry was performed in 198 single fetuses. All examinations were done with a Kranzbühler Linearscanner using an ADR 3.5 MHZ transducer. Growth curves and the velocity of growth from biparietal diameter and from crown-rump length were determined and compared. The accuracy of the estimation of gestational age was observed to be +/- 10 days (2 SD) with both methods. A difference in accuracy could not be found. Even if the first half of pregnancy was separated in an early and a late part there wasn't any improvement of accuracy.

Cephalometry↗
PubMedDate not supplied

[Possibilities for error in the pulsed Doppler method for measuring blood flow in the fetus].

Fetal blood flow volume was measured non-invasively by means of a pulsed Doppler instrument in 35 patients between the 30th and 41st week of gestation. In the descending fetal aorta the mean blood flow volume was 230 +/- 44 ml/min/kg, in the umbilical vein 121 +/- 27 ml/min/kg. The relatively large range of the individual variations from the mean value (up to almost 20%) was due to 1/2 to the determination of the vessel diameter and to 1/2 to the Doppler measurement itself. The investigations performed show that the Doppler technique permits a rough quantitative statement about fetal blood flow volume. However, the relative large range of variation does not allow a clinical assessment, to date.

Aorta↗
PubMedDate not supplied

[The importance of measuring both umbilical arteries for accuracy in Doppler ultrasound studies].

In a quarter of our Doppler investigations differences between the S/D-ratios of the arteries of one umbilical cord were more than 20%. In these cases one Doppler value was decided to be normal and the other to be pathological. In cases with two pathological values most caesarean sections because of fetal distress had to be performed and most SGA babies were born. There were relatively more caesarean sections and SGA babies in cases with one normal value and one pathological value than in cases with two normal Doppler values. Sensitivity and specificity of perinatal risks like intrauterine growth retardation or caesarean section because of fetal distress were different depending on which Doppler value was used to calculate these statistical parameters. Taking always the better values compared to the worse ones we found as greatest difference 20.0% for sensitivities and 24.1% for specificities. Taking the means of the better and the worse Doppler values we found as greatest difference 5.6% for sensitivities and 8.7% for specificities compared to the cases with two identical Doppler results. To decide whether the fetus is jeopardized and to describe the nutritional function of the placenta correctly by means of Doppler ultrasound of the umbilical artery we conclude that in some cases the investigation of both arteries is important to avoid false positive or false negative results.

Blood Flow Velocity↗
PubMedDate not supplied

[The value of Doppler ultrasound studies in threatened premature labor].

95 patients were investigated using Doppler ultrasound to evaluate its usefulness during the clinical management of patients with preterm labor, preterm rupture of membranes and incompetent cervix. Cases with additional pregnancy complications as preeclampsia or intrauterine growth retardation or infection of the amnion or the birth canal were excluded from our study. We examined the umbilical artery and the uterine arteries. Predicting preterm birth we found a sensitivity of 31.4% and a specificity of 70% for the former and a sensitivity of 34.3% and a specificity of 83.3% for the latter. As a result of our investigation we have to conclude that Doppler ultrasound is not able to predict sufficiently reliable preterm birth to use it in clinical management. Normal uterine blood flow in cases with preterm labor seems to indicate birth at term in a high degree.

Adult↗