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M Korell

Publications and source records attributed to M Korell.

44 records · Page 3Linked to original sources

[Current possibilities in reproduction medicine. 2. Spectrum of therapeutic procedures].

As measures of assisted conception, GIFT, ZIFT, TV test and insemination require patent Fallopian tubes. In the majority of cases, intra-uterine insemination is attempted before the invasive methods. Intratubal gamete transfer is employed in particular in the case of infertility that has resisted treatment for years, some forms of male subfertility, and in patients with endometriosis or other forms of genital pathology. In addition, ZIFT and the TV test permit an assessment of in vitro fertilization. In the case of IVF, the classical indication of microscopically non-treatable tubal occlusion has been expanded considerably. Although GIFT is associated with a pregnancy rate of between 30 and 40%, IVF is increasingly being used in women in whom GIFT is indicated, thus avoiding the need for laparoscopy. The alternative techniques of transvaginal GIFT or transvaginal embryo transfer cannot yet be definitively evaluated for clinical routine use. In view of the wide range of therapeutic possibilities, individual counselling of the patient is an essential requirement.

Embryo Transfer↗

Dynamic glenohumeral joint stability.

Stability of the glenohumeral joint with an anterior, posterior, and inferior displacement force of 50 N was measured in a dynamic shoulder model. Controlled hydrodynamic actuator forces were applied to the deltoid muscle and to the rotator cuff in seven anatomic specimens. During elevation of the arm the position of the humerus was measured with a six-degree-of-freedom ultrasonic sensor device. The rotational center of the humeral head was used as a reference point for translation. A displacement force of 50 N led to significant humeral head displacement anteriorly and posteriorly but not inferiorly. A 50% reduction of rotator cuff forces increased anterior displacement by 46% and posterior displacement by 31%. Venting of the glenohumeral joint space and of the subacromial bursa resulted in a 50% increase of anterior displacement, a 19% increase of posterior displacement, and significant inferior displacement. This study demonstrates that in addition to passive stabilizers and negative intraarticular pressure, rotator cuff force significantly contributes to stabilization of the glenohumeral joint during arm motion. Muscle strength and coordination should gain more emphasis in the diagnosis and treatment of shoulder instability.

Adult↗

[A new vacuum extraction system with a ball joint and detachment warning--in vitro studies and clinical use].

BACKGROUND: The vacuum extractor is used in about 5% of deliveries. It is associated with a lower maternal morbidity than is forceps extraction. On the other hand, cephalhematomas, hyperbilirubinemia and cerebral hemorrhages in the baby are observed more frequently. The sudden detachment of the vacuum extractor with appreciable fluctuations in intracranial pressure in the baby is especially dangerous. In order to improve the conventional Malmström system, we have developed a new vacuum extractor and investigated its handling in vitro and in clinical application. PATIENTS AND METHODS: The essential constructional principle of the new vacuum extractor consists in a pivot lowered by ball bearings and a volume reduction of one third. Moreover, in two-chamber vacuum it is possible to give a warning of sudden detachment. The possible tractional force in kiloponds was determined at various angles (0 degree, 15 degrees, 30 degrees und 45 degrees) comparing the Malmström extractor with the new one and two-chamber system in a standardized apparatus. In addition, the new vacuum extractor was also used clinically in 43 women; besides the obstetric parameters, the handling was also appraised. RESULTS: In the in-vitro experiments, a distinct decrease of the possible tractional force with increasing angles was shown for the Malmström extractor (0 degree--15.7 kp, 15 degrees--12.7 kp, 30 degrees--8.6 kp, 45 degrees--7.3 kp). The values for the new one-chamber system were significantly greater from a tractional angle of 15 degrees (0 degree--15.6 kp, 15 degrees--14.4 kp, 30 degrees--14.0 kp, 45 degrees--13.8). The clinical application of the new vacuum system was unproblematic and confirmed the feasibility of good traction. A very much smaller caput succedaneum was found in the baby. Especially in the training situation, the warning system enables a good surveillance before sudden detachment, but reduces the possible tractional force. CONCLUSIONS: The new vacuum system appears to enable the vaginal surgical delivery to be improved compared to the conventional Malmström extractor. After these promising approaches, a multicenter study was commenced in order to enable better evaluation of their clinical significance.

Equipment Design↗

[Measurement of glenohumeral joint translation with a dynamic shoulder model].

Translation of the glenohumeral joint was measured with a dynamic shoulder model, during elevation of the arm in eight cadaveric specimens. Controlled hydrodynamic actuator forces were applied to the deltoid muscle and the rotator cuff through wire cables. Using a constant force ratio, the glenohumeral joint was elevated to 90 degrees. The position of the arm in all spatial orientations was measured with an ultrasonic device. Reproducibility of glenohumeral joint motion was demonstrated on the basis of five cycles of glenohumeral joint elevation. The rotational center of the humeral head was used as the reference point for translation. Translation during elevation of the glenohumeral joint between 20 degrees and 90 degrees averaged 9.0 mm +/- 5.2 mm superiorly and 4.4 mm +/- 1.3 mm anteriorly. In vivo, this may be diminished by coordinated activity of the rotator cuff. The presence of significant glenohumeral joint translation underlines the importance of active, muscular guidance at the shoulder. Physiologic translation of total shoulder arthroplasty, in shoulder instability and in the impingement syndrome.

Adult↗

Experimental animal model for readhesion formation study.

The problem of postoperative adhesions remains unsolved. The formation of readhesions after tubal reconstructive surgery reduces the success rate. We have developed a modified uterine horn model in the rat to study the influence of peritoneal transplants on readhesion formation. A total of 58 rats were operated. In 25 animals (group III) the uterine horn was scratched on both sides and then sutured together. During relaparotomy 14 days later the tight connection between both sides was cut. The resulting defect was covered by a peritoneal transplant on one side (group IIIb) and was left open on the control side (group IIIa). After 14 days the presence or absence of adhesions was explored. There was a significant difference (p < .001) between the covered (28%) and uncovered (84%) peritoneal defects with respect to incidence of adhesions. To compare the different characteristics of visceral and parietal peritoneum, a pelvic sidewall defect was induced in 33 animals. There was no significant difference between covering the defect by a peritoneal transplant (group II; 42.9%) and the control side (group I; 33.3%). These data suggest that defects on visceral peritoneum should be closed to prevent adhesion formation. The incidence of adhesions after injury of parietal peritoneum seems to be much lower and of less clinical significance.

Animals↗

[Course of pregnancy following in vitro fertilization and embryo transfer].

Worldwide analysis of pregnancies after IVF/ET allows the evaluation of the pregnancy outcome compared to normal population. The mean age of IVF-patients is significantly higher. The incidence of clinical abortions after IVF/ET is within normal range, correlating rather with age than with treatment modalities. The rate of multiple gestations is increased after IVF/ET as well as GIFT or hMG-stimulation, leading to more high risk pregnancies. Gestosis is seen in 7% of singletons and 17% of triplet pregnancies. Preterm deliveries before 36 weeks of gestation occur in 17% of singleton and 52% of twin pregnancies after IVF/ET (control 7.3%). This leads to an increasing rate of caesarean section. The global malformation rate is 2% and in a comparable range to normal population. A presumably higher incidence of neural tube defects has to be proven in a larger number of IVF pregnancies.

Embryo Transfer↗