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In this study we investigated shape and value of ion current by measurement using round probes in the coating chamber with three simultaneously operating cathodes. A simple model with a macroscopic approach of the problem for the angular and distance distribution of the ion current is used to calculate the quantitative and qualitative relations between the shapes and the absolute values of the arc current and the ion current in the coating chamber. The model consists of three parts. Each of them describes the spots' movement and splitting during pulse and d.c. phases, depending on its own and the external magnetic fields, the geometrical ion current distribution and the processes on substrate, where e.g. implantation and sputtering depend on bombarding angle. Good agreement is found between the results derived from numerical simulation and experiment.

A combination of steered arc process and modified pulsed arc process was investigated in order to determine the effects on the plasma and on the coating qualities during deposition. Titanium, titanium–aluminium and chromium were used as target materials. The work pressure was 1 Pa with nitrogen as work gas. The usage of a pulsed arc current instead of a continuous arc current leads to an accelerated spot movement during the pulse period. The pulse phase also causes the division of the formerly single spot into multiple spots. Those multiple spots move on average on the circular trace that can be observed also without pulsed arc currents. Therefore the spot traces and their velocity leave vary only locally while the pulse current is applied. Another trait of the process combination is the attenuation of the plasma focussing compared with the pure modified pulsed arc process. This weakening influences the film thickness uniformity.

As shown in previous publications concerning cathodic arc deposition, the vacuum arc as a technological tool can be very complexly influenced by variation of the electrical arc parameters. The pulsed arc current and the resulting ion current influence the formation of the coating. To determine optimised parameters for the deposition process, the dependence on the frequency, on the rate of current rise and on the maximum pulse current in particular were investigated. Using the variation of the output parameters of a pulsed arc power supply, the ion current was steered in its shape and its absolute values. Therefore, the shape of arc current pulses was varied, especially in the phase of rise and fall (triangle, sine, rectangle). Among other things, it was noted that at the beginning of the pulse an excessive increase in ion current is measurable. In order to use this increase for a more effective coating process, experiments were carried out using pulses with controlled slopes and current levels or double pulses of rectangular shape. The examinations have shown that an increase in the ion current ratio in the arc current can be reached by a suitable choice of the electrical parameters. The plasma can be controlled by the electrical parameters of the current source.

The deposition rate and the film thickness uniformity in a vacuum arc deposition process were investigated with respect to dependence on static and dynamic arc current parameters. Measurements were based on the ion current density. The known relations between the investigated process parameters were verified for the d.c. arc process and served as a reference. In the modified pulsed arc process a considerably increased ion current density was measured (up to 1.2 mA A -1 cm -2 during a 500-A pulse). The angular distribution changed in dependence on maximum pulse current especially and could be measured to be cos 3 φ for I p = 150 A to cos 7 φ for I p = 500 A. This results in very high deposition rates in the central region of the substrate and in changes of the film thickness uniformity. A maximum increase of the deposition rate by a factor 3 (perpendicular to the cathode) was measured. Only in a smaller sector the distribution of the film thickness can be approximated by a cosine function (with exponent n up to 27).

The interaction of the substrate temperature and the deposition rate in a vacuum arc deposition process were investigated with regards to dependence on static and dynamic arc current parameters. Two different deposition systems both for industry as well as for laboratory application distinguished in shape and volume of the recipient were used for the experiments. In reference to the d.c. process one can achieve the same deposition rate at a noticeably lower substrate temperature when using the modified pulsed arc process. Furthermore, it is obvious without a detailed analysis that the quality of the coatings deposited by the pulsed arc is fairly higher. In order to control the substrate temperature via the pulse parameters the r.m.s. ion current has to be changed (at a constant average current). Using a theoretical model a decreased substrate temperature at higher ion energy was found.

Objective: Peritoneal irritation by cold CO 2 gas is possible cause of pain after laparoscopy. The aim of this study was to evaluate whether insufflation with warmed CO 2 is associated with less postoperative pain than insufflation with unwarmed CO 2 . Methods: Three hundred patients scheduled for operative laparoscopy were randomly assigned to receive unwarmed (n=150) or warmed (n=150) CO 2 at insufflation. Postoperative pain was assessed on a pain scale. Results: The amount of CO 2 insufflated and the duration of surgery did not differ between the groups. The maximum temperature of the warmed insufflated CO 2 was 33.5°C. The intraabdominal temperature during surgery declined by an average of 3.9°C in patients receiving unwarmed and 2.1°C in those insufflated with warmed CO 2 . Postoperative pain intensity did not differ between the two groups. There were no differences in timing or requirements for postoperative pain medication or in postoperative nausea, vomitting and chills. Conclusion: These data suggest that insufflation with warmed CO 2 does not reduce postoperative symptoms in patients undergoing operative laparoscopy.

The processes d.c. arc, modified pulsed arc, d.c. steered arc and the combination of steered and pulsed arc were compared. Steered arc cathodes with different magnetic fields were used to obtain experimental results for spot movement, ion current, layer formation and droplet emission. The process combination of steered and pulsed arc was examined mainly. High-speed videos showed a clearly increased spot velocity and the enlargement of the eroded area. Measurements on total ion current verify the experiences of random pulsed arc. The angular distribution of ion current density led us to conclude a focused plasma column. In this case, the influence of the duty cycle is strongest. For example, the ion current density related to arc current in the perpendicular direction is increased by 35% for steered arc with pulses. Deposition experiments yielded an increased deposition rate and a reduced droplet density. Results available up to now need further confirmation. The influence of the magnetic field intensity has to be investigated systematically.

The modified pulse arc process is a new development for the deposition of thin films. TiN, CrN and TiBN were deposited on stainless steel and polished high speed steel. The emission of droplets was investigated using the commercial d.c. cathodic arc deposition and the modified pulse arc deposition. For a global expression of deposited droplets the surfaces were scanned with a profilometer. The droplet density was established by counting of droplets in scanning micrographs of thin film surfaces. The results of analysis show that the new process can reduce the deposited droplets. However, this is influenced by the pulse parameters. The chemical composition of the films is independent of the used deposition process.

The ion emission in pulsed and d.c. vacuum arc discharges was investigated in dependence on static and dynamic arc current parameters. Three different power supplies were used with the following pulse currents and durations: 100 A, 3 μs; 500 A, 1 ms; 1000 A, 100 μs. Mainly the angular distribution of ion current density, the total ion current and the maximum velocity of emitted ions were investigated. It was observed that the ion emission occurs preferentially in a direction perpendicular to the cathode plane (0°). The focusing effect increases at higher pulse current values. Therefore the highest ion current density related to arc current was measured at 0° to be 2.6 mA cm−2 A−1 during a 1000 A pulse. This value decreases to 1/10 at 45°. The total ion current was estimated to be 40–50% of the arc current as maximum during the 1000 A pulse. Furthermore the ion velocity was measured with the help of time-related measurements. In general the values are higher at rates of higher current increase. However, there was an angular distribution. At higher angles relative to cathode normal the measured ion velocities are 2–3 times higher than at the 0° position. Collision effects were supposed to be the reason. Furthermore, calculations show the probability that the average ion charge is clearly increased compared with d.c. during current pulses with a high rate of increase. From measurements at 1000 A pulses one can estimate an increase by 1.7. Some investigations were carried out under high vacuum conditions and others at higher pressures with nitrogen. Most of the changes determined become smaller at higher pressures.

There is some controversy about the use of laparoscopic procedures for dermoid cysts since they involve the risk of abacterial peritonitis and of malignant growths produced by surgery. From 1992 to June 1996 we performed 208 operations for teratoma. Laparoscopy was sufficient in 184 cases (88%), while laparotomy had to be performed in 24 cases. In 14 cases (8%) the laparoscopic procedure consisted of adnexectomy or ovariectomy; in all other cases it was possible to preserve the organ. The mean age of the patients treated by laparoscopy was 34 years. In the laparotomy group the mean age was 41 years. The average sonographic diameter of the dermoid cysts removed by laparoscopy amounted to 5 cm (range 1.3 -10 cm), the cysts removed by laparotomy measured 8cm in diameter on an average (range 4-17 cm). Slight complications developed in 5% of the cases following laparoscopy, such as laceration of epigastric vessels, a drop in Hb of less than 8 g %, which did not require a transfusion, temperature above 38°C as well as subileus. In that particular patient two endometriosal cysts had been removed at the same time. None of the cases required a repeat procedure. Two malignant teratomas were found in these 208 cases, namely, a 17 cm solid teratome in a 77-year-old patient and a tumour of the size of a child's head in the lower abdomen in a 26-year-old. Both patients were initially treated by laparotomy. Only rarely is it possible to remove the entire dermoid cyst via a Lap Sac without contaminating the abdominal cavity with the contents of the cyst. Careful washing of the abdomen using saline solution at body temperature is obligatory to prevent abacterial peritonitis. Adnexectomy via Lap Sac or by means of laparotomy is therefore the procedure of choice in postmenopausal women. In young patients we consider laparoscopy to be the method of choice too. If, however, a malignant teratoma is suspected, tumour of rapid growth, large solid tumour, or adhesions, laparotomy is indicated in most cases.

From 1987 to 1991 a total of 5035 pelviscopies were done at the Kiel University Hospital of Gynaecology. More than 90% of these were surgical pelviscopies, whereas less than 10% were diagnostic procedures only. Serious complications requiring laparotomy or repeat pelviscopy or laparotomy within 4 weeks after the original procedure, occurred in 2.0% of the cases and slight complications were seen in 2.9%. Procedures for acute abdomen or adhesiolysis after multiple laparotomies bore the greatest risk of serious complications. Low risk was associated with sterilisations, procedures for female sterility, endometriosis or tubal pregnancy.

This paper describes a new “modified pulse arc evaporation process” which represents a combination of both d.c. and pulse cathodic arcs. The aim is to give a comparative overall view. The paper reports on measurements of spot movement on the target, arc voltage response and ion current under different electric conditions, such as current magnitude, current changing rate and pulse duration. There are possibilities to improve the target consumption; to reduce the upper stability limit; and to increase the spot velocity (from 6 m s −1 to more than 30 m s −1 ), the bias current density in the pulse phase (some 100% higher) and the plasma power. For optical measurements of spot movement a new high-speed video camera (40 500 pictures per second for a maximum recording time of 1 s) was used.

Between 1992 and 1993 surgery conserving the organ was undertaken in 215 patients with uterine myomas. Only myomas of more than 2 cm in diameter were included. It was possible to conserve the organ in 207 cases (90%). Myomectomy by pelviscopy was performed in 131 cases. The procedure was successful in 117 cases (89%), secondary laparotomy had to be done in 14 of these patients. On average the myomas removed by pelviscopy measured 5.2 cm in diameter. The S.E.M.M. (Serrated Edged Macro Morcellator) was used in the procedure. It did not take long to morecellate even larger myomas (the largest one removed by pelviscopy weighed 418 g) and to remove them by means of a 15 mm-trocar. An average of 2 myomas were removed per patient (r: 1-5). The mean Hb drop amounted to 1.5 g%. Repeat pelviscopy had to be done in one patient because of a secondary haemorrhage, a laparotomy and hysterectomy for subilius had to be performed in one case on the 3rd postoperative day. An intestinal loop has adhered to the uterine wound dehiscence. No other complications were observed after pelviscopic myomectomy. A 41-year-old patient wanting children suffered a late complication, namely a ruptured uterus in the 28 w of pregnancy. It is therefore imperative to inform patients who are still in the reproductive phase about the possibility of an uterus rupture after pelviscopic myomectomy.

Summary This work deals with the localization and chronology of the appearance of tissue-plasminogen-activator (t-pa) in coagulated and vaporized peritoneal lesions. 21 female WISTAR-rats were laparotomized, similar areas of the parietal peritoneum being vaporized and coagulated. The excision of these lesions was done at seven preset time intervalls from 0 to 48 hours postoperatively. The occurence of t-pa and fibrin was shown by immunohistochemical staining of cryo- and plastic-embedded sections. The differentiation of cells was done with immuno- and enzymhistochemical techniques. The inflammatory response of vaporized lesions shows to be more intense, i. e. exsudation of more fibrin, higher amount of inflammatory cells and a strongly emphasized tendency of adhesion-formation. There is a very low amount of t-pa-reactive cells up to 12 hours postoperatively, increasing after 24 and 48 hours but staying low in relationsship to the total amount of cells. In coagulated lesions there is a steady increase of t-pa-reactive cells up to 12 hours postoperatively. Adjacent undamaged peritoneal areas in both types of lesions show a significant t-pa-reactivity. The visible reactivity to t-pa can be localized almost exclusively around monocytes and peritoneal macrophages. Both types of lesions do contain closely the same number of KiM2R-reactive mononuclear cells. There is an increased number of mastcells in vaporized lesions. There is more research needed to be done on the influence of different traumatic impacts on the peritoneum in order to find a causal approach to prevention of adhesions. Right now the only causal way to minimize the incidence of iatrogenic postoperative adhesions is the use of the Semm's well known Endo-coagulation-Technique.

In 1988 and 1989 176 patients underwent pelviscopy at the Kiel University Hospital of Gynaecology for primary or secondary sterility of at least 12 months duration. 120 patients (68%) filled in a questionnaire on the therapeutic results after 2 to 3 years. Following peripheral salpingostomy in 18 patient, an intrauterine pregnancy developed in 22% of these cases, while an ectopic pregnancy occurred in 11% of the cases. After fimbrioplasty in 37 cases, the intrauterine pregnancy rate amounted to 43%, whereas the rate was 50% following salpingoovariolysis. 4 patients with a subserous or intramural myoma, measuring 2.5 to 8 cm in diameter, but no other pathological signs of disturbed fertility, became pregnant after enucleation of the myoma. 2 patients delivered at full term, the other two miscarried. 5 out of a total of 10 patients became pregnant after endometriosis foci had been coagulated or endometriomas enucleated. In these cases, the adnexa did not require additional surgical treatment. Pelviscopy revealed an untreatable intratubal block in 9 cases. 10 patients could not be included in the study, either because of a successful in vitro fertilisation or a pregnancy following heterologous insemination or because a hysterectomy or tubectomy had been performed in the meantime. In cases, where inspection under magnification had shown at least one non-pathological adnexa and tubal patency of at least one of the tubes, 35% of the patients conceived after pelviscopy and chromopertubation within the follow-up period. The therapeutic action of the chromopertubation and the psychological effect of finding no pathological signs during the genital examination remains speculative.(ABSTRACT TRUNCATED AT 250 WORDS)

In 74 patients suffering from chronic pain in the lower abdomen and highly vascularised or involved adhesion of organs, as the only pathological finding, pelviscopic adhesiolysis was performed with conventional pelviscopic techniques, whereas, in 69 patients, a YAG contact laser was employed. At discharge from hospital 3-5 days later, more than 80% of the patients were free from complaints or stated a slight relief. At follow-up after 6 months, the respective figures in both groups were reduced to 49% and 52%. Almost 30% of the patients, who had reported short-term relief, finally renewed their complaints. Laser can offer advantages, with respect to surgical techniques employed in pelviscopic adhesiolysis. It enables cutting practically without bleeding, with a narrow lateral zone of necrosis, and can therefore be employed, even closely adjacent to the intestine. There were also no significant differences in respect of recurrences of adhesions in repelviscopy, after pelviscopic laser adhesiolysis, compared with conventional techniques.

Between 1984 and 1989, 773 patients less than or equal to 45 years of age, presenting with a total of 809 ovarian cysts, underwent pelviscopy at the Department of Obstetrics and Gynecology of Kiel University. In 36 cases, cysts were bilateral. 678 cysts (84%) were treated by pelviscopy alone. Organ-preserving treatment was performed in 83%, oophorectomy or adnexectomy in only 17% of cases. Two stage Ia ovarian carcinomas (0.26% of all cysts) were operated on by pelviscopy before laparotomy. Sonography is particularly important in determining whether a pelviscopic approach is appropriate. Pelviscopic procedures are unacceptable in multilocular cysts measuring greater than or equal to 7 cm in diameter with echo-dense components. Special caution is required for any cyst measuring greater than 9 cm in diameter. The risk of opening a malignant cyst must be weighed against the advantages of pelviscopic surgery: minimal physical strain, better postoperative quality of life, and organ conservation. In doubtful cases, laparotomy is recommended.

Coagulation and vaporization of tissue are techniques applied in pelviscopic surgery in order to achieve hemostasis as well as cut and destroy endometriotic implants. An animal experimental study was devised to show if there is a difference in the incidence of adhesions after vaporization of equal-sized areas of the anterior abdominal wall of the rat compared to coagulation of equal-sized areas. A similar depth of the lesions was achieved by repeating the vaporization procedure. The rate of adhesions was significantly lower (P less than 0.001, Chi2-test) post-coagulation, using a biopolar high frequency current or post-endocoagulation than post-vaporization. The surface vaporization of tissue, for example endometriotic implants, as produced by laser is to be viewed critically as regards the higher incidence of adhesions after vaporization compared with coagulation.

From 1977-1989, 298 ectopic pregnancies were treated pelviscopically at the Dept. of Gynaecology Hospital of the University of Kiel. 26 tubes were already ruptured. In 251 patients (84%), organ preserving treatment was possible, 205 treatment by longitudinal salpingotomy. 46 tubal abortions were extracted. In 47 patients (16%), who did not wish to augment their family any further, or in whom recurrence of tubal pregnancy occurred on the same side, salpingectomy was performed. Complications required re-pelviscopy in 5% and laparotomy in another 1%. The intrauterine pregnancy rate in 143 patients desiring pregnancy was 58%. Abortions occurred in 8%. A recurrence of ectopic pregnancy in the ipsilateral tube occurred in 10%, in the contralateral tube in 6%. 9 patients desiring pregnancy had already undergone salpingectomy on the contralateral side or were treated pelviscopically by longitudinal salpingotomy because of ectopic pregnancy on both sides. Three of them gave birth to healthy infants.

In 969 patients, we observed 1016 ovarian cysts at pelviscopy between the years 1984-89. 36 of these were non-benign. On the basis of the pre- and intraoperative findings (palpation, sonography, inspection of the cyst surface under eye-glass magnification) we treated 827 cysts exclusively by pelviscopy, 189 cysts by laparotomy. Laparotomy was preceded by pelviscopic surgery on the cyst in 94 cases. None of the pre- and intraoperative findings completely eliminated the risk of performing pelviscopic surgery on a stage Ia carcinoma; indeed, this occurred in 2% (2/1016).

Between 1983 and 1988, we treated 66 patients with pelvic abscesses. Twenty-five patients required laparotomy and 41 underwent pelviscopy for treatment. The choice of the operative procedure, laparotomy or pelviscopy, depended on the age of the patient, the clinical presentation and the operative findings. The two collectives demonstrated no differences in the duration of hospitalization and in-patient treatment with antibiotics. A conservative, organ-preserving procedure could be performed in 80% of patients operated pelviscopically. In follow-up examinations 1-2 years after operation, 27% of the patients treated per pelviscopy complained of chronic abdominal pain as compared to 37% of those treated per laparotomy. In young patients, pelviscopic treatment of pelvic abscesses is a valuable alternative to laparotomy.Physicians at Christian Albrecht University Hospital in Keil, West Germany treated 66 women with pelvic abscesses between 1983-1986. Pelviscopically treated patients were younger than laparotomy treated patients and IUD usage occurred 17% vs. 20% respectively. They 1st treated many patients with ampicillin and metronidazole or ampicillin and clavulanic acid. They were able to perform pelviscopy on 25 of the 33 patients with inflamed Fallopian tubes. 9 of these women experienced either a uni- or bilateral salpingectomy or salpingo-oophorectomy. They were able to do an organ preserving procedure designed to preserve fertility in 80% of the women, especially pelviscopically treated patients (81% vs. 16% laparotomy patients). They performed a laparotomy on the 6 patients with bilateral total abdominal tuboovarian abscesses. Of the 25 women who underwent a laparotomy, 20 required only a uni- or bilateral salpingectomy or salpingo-oophorectomy and 5 required a total hysterectomy and bilateral salpingectomy. No differences existed between pelviscopically and laparotomy patients in number of days in the hospital and duration of inpatient antibiotic therapy. Even though more laparotomy treated patients (37%) experienced chronic abdominal pain following treatment than pelviscopically treated patients (27%), the laparotomy patients initially experienced more severe and extensive infections than did pelviscopically treated patients. Of the 45 patients who were able to be examined 1-2 years after surgery, only 3 experienced recurrent pelvic inflammatory disease (8% of pelviscopically treated patients and 5% of laparotomy patients) which the physicians found encouraging since pregnancies may occur. In conclusion, to preserve fertility, they advocated pelviscopy along with organ preservation for patients in their reproductive years.

We analyzed the case histories and operation protocols of 2,465 female patients who had undergone pelviscopy for various reasons at the University Clinic of Obstetrics and Gynecology, Kiel, in the years 1978-1982. 1,743 patients (71%) had reported a previous appendectomy, of whom 965 had had no other intra-abdominal operation. 657 of the latter (68.1%) presented adhesions; these were located in the right middle abdomen in 36.4% of the cases. In comparison to a collective of 308 patients without adhesions after appendectomy, the existence of chronic lower abdominal pain was independent of the presence of adhesions (30-31% in both groups). In 55% of the patients with adhesions who were infertile after appendectomy, periovarian and peritubal adhesions were registered. In order to avoid unnecessary appendectomy or other laparotomies with later formation of adhesions, the use of laparoscopy is recommended in all questionable cases.

Resulting from the constantly increasing number of electrical and electronic appliances in both commercial and private spheres and the ongoing process of standardisation in the field of electromagnetic compatibility, there is a growing consciousness regarding possible electromagnetic interference problems of appliances. In the case of resistance welding equipment, special attention is paid to the occurring electromagnetic emissions because of the high rated-power parameters and the intermittent operation of these devices. Different noise mitigation measures, considering the special characteristics of the generation and propagation of disturbances in the case of resistance welding inverters are discussed in this paper.

Resulting from the connection between the change rate of a magnetic field and the induced currents in an exposed human body, pulsating magnetic fields have to be evaluated analyzing the waveforms of the field or the field-generating current. Considering the specific output current waveforms of resistance welding installations in the paper appropriate procedures to determine the waveform-dependent exposure limits are explained by the example of a resistance welding inverter. Based on investigations of the field distribution the actual flux density values are compared to the ascertained exposure limits.

Nowadays simulation tools are widely used in the design process of power sources for arc and resistance welding. A modern inverter-type welding power source is a complex power electronic system, which is characterized by high switching frequency, fast dynamic response and a special load adapted process control. Although for an overall simulation on the system level simple semiconductor models may be sufficient, some relevant problems can only be solved on a circuit level simulation considering dynamic semiconductor models, driving circuits and parasitics. In this paper experiences with the practical parameterization and application of some recently introduced data sheet based models of diodes. MOSFETs and IGBT are described.

The droplet emission in a modified pulse arc process was investigated in relation to the DC random arc process. Nitride coatings were deposited on surfaces of stainless steel and of polished high speed steel. Ti, Cr and TiB (96:4 at%) were inserted in the deposition arrangement as target materials. The special melting points of these target materials makes a different behavior of the cathodic arc discharge possible. The deposited layers were analysed on the droplet number, droplet size and droplet shape. Furthermore the surface roughness was measured. The structure and the stoichiometry were tested. It was found that the modified pulse arc deposition reduces the droplet emission. By using the modified pulse arc process, the surface roughness of TiN decreases about 20% in comparison to DC mode deposited TiN layers. The modified pulse arc process has no influence on layer structure and layer composition.

In the paper, existing possibilities to localize sources of disturbance within resistance welding inverter topologies are illustrated. Furthermore, the effects of the application of mains filters and noise suppression capacitors are also discussed.

Objective : To assess the risks of complications including intraoperative spillage following laparoscopical dermoid cyst enucleation. Study design : A retrospective case series comparison of 390 patients who had surgery at our hospital from 1992 to 1998 for teratomas of the ovary. Results : 43 patients were treated with laparotomy. Two malignant teratomas were observed in this group. In seven patients, the dermoid cysts were removed as part of a vaginal hysterectomy. Three hundred and forty patients had surgery via laparoscopy. Enucleation of the dermoid cyst in toto using a salvage bag for removal was only possible in few cases without contamination of the abdominal cavity by spillage of cyst contents. There were no serious complications in any patients including those with laparoscopic cystectomies and intraperitoneal spill. Conclusion : The laparoscopical treatment of benign teratomas is a safe procedure. Primary laparotomy as well as adnectomy is also to be taken into consideration with young patients, if suspicion of malignancy, rapid growth, doubtful infiltration or large size of tumor is present.

Even today, the situation is still unclear with regard to the radicality of the operation and any adjuvant therapy required in treatment of borderline tumors of the ovary. In the last two decades, treatment of these tumors in the Department of Gynecology and Obstetrics at our hospital has depended on the stage of the disease and the age of the patient. It ranged from laparoscopic cyst extirpation to hysterectomy with bilateral adnectomy and omental resection and regional lymphnodectomy. From the end of 1985 to the end of 1992, 35 patients with borderline tumors of the ovaries were operated on. Histologically, 14 borderline tumors were mucinous, 21 were serous. A follow-up investigation was carried out five to 11 years after primary operation. In this period, no patient died of borderline tumor. Twenty-eight patients who were followed up were clinically free of recurrence, five patients are alive, but could not be followed up. Two patients have died of other diseases after five years. Only one patient received adjuvant chemotherapy. She could not be followed up. In the meantime, peritoneal implants were demonstrated at second-look laparoscopies in four out of 18 patients. Later, these could no longer be demonstrated (one patient) or did not affect the survival time (three patients) and thus ultimately was not pathologically relevant. Primarily, two of these four patient had stage Ia-Ic. The paraffin blocks of the preparations are still available from 26 patients, and additional investigations could be carried out. Nineteen percent of the borderline tumors showed micropapillary structures of an MPCS (= micropapillary serous carcinoma), which evidently did not have a negative effect on the prognosis. All borderline tumors showed diploid distributions in DNA cytometry. It is not possible to make a definitive treatment recommendation on the basis of this investigation because the number of patients followed up was too small.

The arc is the technological tool in the arc welding process. Improved welding quality requires precise control of the arc in all different welding phases. This paper presents some possibilities of arc control for the gas-metal-arc welding process, by using the conventional electrical parameter range and an extended electrical parameter range achieved by an auxiliary power electronic circuit. Another way is to use an external magnetic field for controlling the arc.

From 1987 to 1991 a total of 5035 pelviscopies were done at the Kiel University Hospital of Gynaecology. More than 90% of these were surgical pelviscopies, whereas less than 10% were diagnostic procedures only. Serious complications requiring laparotomy or repeat pelviscopy or laparotomy within 4 weeks after the original procedure, occurred in 2.0% of the cases and slight complications were seen in 2.9%. Procedures for acute abdomen or adhesiolysis after multiple laparotomies bore the greatest risk of serious complications. Low risk was associated with sterilisations, procedures for female sterility, endometriosis or tubal pregnancy.

This study compares the incidence of adhesions after using the Endocoagulator by Semm with the incidence of adhesions after using the Nd-YAG-laser with 30 watts and 100 watts. At a total of 100 female Wistar-rats both, the uterine-horns and 2 correspondent spots at the ventral abdominal-walls were coagulatet. resp. vaporized. After 14 resp. 28 days a relaparotomie was made: 1. With the Nd-YAG-laser (30 and 100 watts) (significant) adhesions were found, at the uterine-horns in 100% of all cases with the Endokoagulator in 50%. At the peritoneal spots with the Nd-YAG-laser (30 and 100 watts) (not significant) adhesions were found in 10% of all cases, with the Endokoagulator 5% were found. 2. In addition to the macroscopic results histologic researches were also made: It was shown, that the treatment with Nd-YAG-laser develops a high grade of carbonisation-waste, which is known to be a main cause for the development of adhesions. 3. The division in 14- and 28-day-groups showed no significant differences in the incidence of adhesions. 4. There were found more significant adhesions at the uterine-horns than at the peritoneal-spots.

Between 1992 and 1993 surgery conserving the organ was undertaken in 215 patients with uterine myomas. Only myomas of more than 2 cm in diameter were included. It was possible to conserve the organ in 207 cases (90%). Myomectomy by pelviscopy was performed in 131 cases. The procedure was successful in 117 cases (89%), secondary laparotomy had to be done in 14 of these patients. On average the myomas removed by pelviscopy measured 5.2 cm in diameter. The S.E.M.M. (Serrated Edged Macro Morcellator) was used in the procedure. It did not take long to morecellate even larger myomas (the largest one removed by pelviscopy weighed 418 g) and to remove them by means of a 15 mm-trocar. An average of 2 myomas were removed per patient (r: 1-5). The mean Hb drop amounted to 1.5 g%. Repeat pelviscopy had to be done in one patient because of a secondary haemorrhage, a laparotomy and hysterectomy for subilius had to be performed in one case on the 3rd postoperative day. An intestinal loop has adhered to the uterine wound dehiscence. No other complications were observed after pelviscopic myomectomy. A 41-year-old patient wanting children suffered a late complication, namely a ruptured uterus in the 28 w of pregnancy. It is therefore imperative to inform patients who are still in the reproductive phase about the possibility of an uterus rupture after pelviscopic myomectomy.

This work deals with the localization and chronology of the appearance of tissue-plasminogen-activator (t-pa) in coagulated and vaporized peritoneal lesions. 21 female WISTAR-rats were laparotomized, similar areas of the parietal peritoneum being vaporized and coagulated. The excision of these lesions was done at seven preset time intervals from 0 to 48 hours postoperatively. The occurrence of t-pa and fibrin was shown by immunohistochemical staining of cryo- and plastic-embedded sections. The differentiation of cells was done with immuno- and enzymhistochemical techniques. The inflammatory response of vaporized lesions shows to be more intense, i.e. exsudation of more fibrin, higher amount of inflammatory cells and a strongly emphasized tendency of adhesion-formation. There is a very low amount of t-pa-reactive cells up to 12 hours postoperatively, increasing after 24 and 48 hours but staying low in relationship to the total amount of cells. In coagulated lesions there is a steady increase of t-pa-reactive cells up to 12 hours postoperatively. Adjacent undamaged peritoneal areas in both types of lesions show a significant t-pa-reactivity. The visible reactivity to t-pa can be localized almost exclusively around monocytes and peritoneal macrophages. Both types of lesions do contain closely the same number of KiM2R-reactive mononuclear cells. There is an increased number of mastcells in vaporized lesions. There is more research needed to be done on the influence of different traumatic impacts on the peritoneum in order to find a causal approach to prevention of adhesions. Right now the only causal way to minimize the incidence of iatrogenic postoperative adhesions is the use of the Semm's well known Endo-coagulation-Technique.

From 1987 to 1990 pelvioscopic distal salpingostomy was performed in 47 patients at the University Hospital of Kiel. The tubal mucosa was everted and fixed with 4/0 PDS sutures. 35 patients (74%) responded to a questionnaire 2-4 years after surgery. A bilateral salpingostomy had been performed in 16 of these 35 cases, while the contralateral tube was either absent or intramurally occluded in 19 cases. Eight patients (23%) postoperatively had an intrauterine pregnancy, five patients gave birth to a healthy child, one patient was pregnant at time of follow-up. Three patients had abortions and three experienced a tubal pregnancy of one or both sides. Compared to the endoscopic procedure with the CO2 laser pelvioscopic salpingostomy with an everted suture represents an equally suited alternative.

From 1985 to 1991, 73 hysterectomies were performed on patients suffering from histologically demonstrated adenomatous hyperplasia, grades 1-3, at the Kiel University Hospital of Gynecology. The operations were done within a month from the diagnosis. Three of the patients were under 40 years of age. An exact correspondence between the grade of adenomatous hyperplasia in the abraded material and the uterus specimen was found in only 44% of the cases. In the patients over 40 with adenomatous hyperplasia of any grade demonstrated in the abraded material, an already well-differentiated endometrial carcinoma was found in 16% of the cases, while such a carcinoma was found in 57% of the cases with grade 3 adenomatous hyperplasia! Even though drug therapy with gestagen may have a beneficial effect, a hysterectomy is nevertheless the treatment of choice for adenomatous hyperplasia of grade 2 and grade 3 in patients over 40 because it is not absolutely certain from a diagnostic point of view that the material is representative of the entire mucosa. In women under 40 years of age it is necessary to plan therapy on an individual basis.

In 1988 and 1989 176 patients underwent pelviscopy at the Kiel University Hospital of Gynaecology for primary or secondary sterility of at least 12 months duration. 120 patients (68%) filled in a questionnaire on the therapeutic results after 2 to 3 years. Following peripheral salpingostomy in 18 patient, an intrauterine pregnancy developed in 22% of these cases, while an ectopic pregnancy occurred in 11% of the cases. After fimbrioplasty in 37 cases, the intrauterine pregnancy rate amounted to 43%, whereas the rate was 50% following salpingoovariolysis. 4 patients with a subserous or intramural myoma, measuring 2.5 to 8 cm in diameter, but no other pathological signs of disturbed fertility, became pregnant after enucleation of the myoma. 2 patients delivered at full term, the other two miscarried. 5 out of a total of 10 patients became pregnant after endometriosis foci had been coagulated or endometriomas enucleated. In these cases, the adnexa did not require additional surgical treatment. Pelviscopy revealed an untreatable intratubal block in 9 cases. 10 patients could not be included in the study, either because of a successful in vitro fertilisation or a pregnancy following heterologous insemination or because a hysterectomy or tubectomy had been performed in the meantime. In cases, where inspection under magnification had shown at least one non-pathological adnexa and tubal patency of at least one of the tubes, 35% of the patients conceived after pelviscopy and chromopertubation within the follow-up period. The therapeutic action of the chromopertubation and the psychological effect of finding no pathological signs during the genital examination remains speculative.(ABSTRACT TRUNCATED AT 250 WORDS)

Pelviscopy was, at its beginning, a purely diagnostic procedure. It was only through the introduction of safe methods of hemostasis, such as endocoagulation, coagulation with high-frequency current, endoligature, and endosuture [8], that operative pelviscopy became possible. The necrotic zone produced by endocoagulation or bipolar high-frequency current is determined by the size of the pelviscopic instrument and is at the very least 0.5 cm in diameter. In the case of high-frequency current, the size of the necrotic zone is in most cases appreciably greater. When employed for procedures on the adnexa, where an atraumatic technique is mandatory in order to maintain the fertility of women in their reproductive years, these methods seem to produce a disproportionate amount of trauma to the tissue. Furthermore, when used in the direct proximity to the bowels bipolar high-frequency current may be problematic, and endocoagulation [7], owing to the largeness of the instrument, may be impossible. In these particular cases the application of laser systems broadens the range of endoscopic operations which may be performed.

In 74 patients suffering from chronic pain in the lower abdomen and highly vascularised or involved adhesion of organs, as the only pathological finding, pelviscopic adhesiolysis was performed with conventional pelviscopic techniques, whereas, in 69 patients, a YAG contact laser was employed. At discharge from hospital 3-5 days later, more than 80% of the patients were free from complaints or stated a slight relief. At follow-up after 6 months, the respective figures in both groups were reduced to 49% and 52%. Almost 30% of the patients, who had reported short-term relief, finally renewed their complaints. Laser can offer advantages, with respect to surgical techniques employed in pelviscopic adhesiolysis. It enables cutting practically without bleeding, with a narrow lateral zone of necrosis, and can therefore be employed, even closely adjacent to the intestine. There were also no significant differences in respect of recurrences of adhesions in repelviscopy, after pelviscopic laser adhesiolysis, compared with conventional techniques.

In 969 patients, we observed 1016 ovarian cysts at pelviscopy between the years 1984-89. 36 of these were non-benign. On the basis of the pre- and intraoperative findings (palpation, sonography, inspection of the cyst surface under eye-glass magnification) we treated 827 cysts exclusively by pelviscopy, 189 cysts by laparotomy. Laparotomy was preceded by pelviscopic surgery on the cyst in 94 cases. None of the pre- and intraoperative findings completely eliminated the risk of performing pelviscopic surgery on a stage Ia carcinoma; indeed, this occurred in 2% (2/1016).

At the University Women's Clinic in Kiel, the YAG contact laser has been used as a cutting instrument in pelviscopic operations since 1987. When the laser cuts, it produces only a scant amount of mechanical trauma. The determining factor is the amount of thermal damage produced along the wound margins and in direct neighboring tissue. The extent of the tissue change seen in the uterus and liver parenchyma of rats and the striated muscle of rabbits after application of the YAG contact laser was demonstrated using various staining techniques and stains. Liver parenchyma proved to be the most sensitive to thermal damage. In the uterine horn, enzyme-histochemical ATPase and alkaline phosphatase demonstrations showed a significantly wider zone of thermal damage after laser incision than did hematoxylin-eosin and Goldner staining techniques. A good understanding of the extent of thermal damage is essential for atraumatic pelviscopic operations using the YAG contact laser and also for the preventing of complications.

Von 1984–1988 wurden an der UFK Kiel 402 Kinder aus Beckenendlage mit 2500 g oder mehr entbunden. Bei 136 Kindern wurde eine vaginale Entbindung durchgefuhrt, 266 wurden durch Sectio entbunden. Der Anteil der vaginalen Entbindungen stieg von 12% im Jahre 1984 auf fast 40% in den folgenden Jahren an. Der Anteil der sekundaren Sectiones war gering und betrug 5%. Wahrend 1984 alle Erstgebarenden in BEL durch Sectio entbunden wurden, stieg der Anteil Erstgebarender unter den vaginal entbundenen Patientinnen in den folgenden Jahren auf uber 40% an. Zwei Kinder mit schweren Misbildungen verstarben nach vaginaler Entbindung. Die Misbildungen waren prapartal sonographisch diagnostiziert. Es handelte sich um ein Potter-Syndrom sowie polyzystische Nieren Typ I Potter. Im Sectiokollektiv verstarb kein Kind.