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D Wallwiener

Publications and source records attributed to D Wallwiener.

At least 145 records · Page 8Linked to original sources
PubMed1996

[Micro-endoscopy, minimal access endoscopy--an overview of current status and future possibilities].

Based on technical and clinical application research a new generation of so-called micro-endoscopes was developed, with a wide range of indications in gynaecology as well. The innovative potential of these new endoscopes is, however, still to be considered against the background of the risks of erroneous findings at laparoscopical and hysteroscopical diagnosis, so that here too, clear indications will have to be worked out.

Female↗
PubMed1996

[Tubal catheterization and fallopian tube endoscopy for expanded diagnosis in tubal sterility].

The present study reports first experiences with falloposcopy for extended diagnosis in tubal sterility. In a total of 38 patients, n = 62 tubes were to be examined falloposcopically. Catheterization was successful in 85.5%. After successful catheterization, optically interpretable images were obtained in 93.6%. The overall success rate was therefore 80%. Considering the anatomical segments of the tube, no differences were found neither for catheterization nor for visualization. The spectrum of intratubal findings extended from normal in 25% to partly obstructive, nodular or non-nodular pictures, together with various degrees of mucosal alteration with or without synechia formation.

Adult↗
PubMed1996

[Abdominal colposuspension: a synopsis of various approaches and techniques including endoscopic modifications].

Though abdominal colposuspension is an established operative procedure in the therapeutic spectrum of female urinary stress incontinence, there is controversy concerning new access routes and fixation techniques. On the basis of a comparison between results of a "feasibility" study at our department concerning the trans- and extra-peritoneal endoscopic access as well as suspension techniques with alloplastic material and suturing vs. stapler application, and al literature survey, a synoptic concept is being evaluated. In case of critically made indication, first trends show that results of laparoscopically and retziusscopically assisted techniques are comparable to those of conventional procedures. However, the lack of long-term results as well as an initially prolonged operation time have to be considered. In the meantime an extraperitoneal transumbilical colposuspension was attempted in 2 patients, already unsuccessfully operated upon (conventional Burch) previously. Due to extensive perivesical adhesions a laparotomy had to be performed. The limits of the endoscopic approach seen to be reached in these cases.

Female↗
PubMed1996

[Possibilities of laparoscopic ultrasound diagnosis].

Both pre-operative transvaginal sonography and laparoscopical diagnosis leave gaps in the diagnosis of adnexal tumors. The combination of both methods seems to fill these gaps. For diagnosis with Laparoscopical Sonography a special scan head is needed: After removing the optical components there was a little linear-array installed into the original gastroscope with a diameter of only 9 mm which enables maximum flexibility during examinations. The linear-array consists of 128 crystals with a frequency of 7.5 MHz (penetration depth: 6 cm), enabling B-Image Sonography, Pulsed and Color Doppler as well as Angio-Color-Technique. Laparoscopical Sonography in addition to transvaginal and transabdominal sonography leads to progress in diagnosis and therapy. As the scan head can be placed directly in front of the area which is normally hardly detectable diagnosis is possible and plannings for the further operations as well as color-doppler controls during operations can be improved. In several cases this method allowed detection of metastases of the liver which were not visible by transabdominal ultrasound.

Equipment Design↗
PubMed1996

[Diagnostic value of Doppler ultrasound in evaluation of breast tumors].

Angiogenesis is an essential condition for tumor growth. Therefore, it seems to be of interest to prove if blood flow and vascularization of breast tumors give information concerning their dignity. Consequently, 205 patients with palpable and/or mammographically detected breast tumors were examined prior to surgery by doppler sonography for blood flow in the area of the tumor. In 174 patients of this group the corresponding area of the contralateral breast was also screened by doppler ultrasound. With third doppler generation angiodynography tumors can be visualized as B-images with simultaneous information on vascularization. An integrated doppler system shows the detected blood flow in form of a doppler curve, also allowing quantification according to doppler criteria (Resistance Index RI). Blood flow detection in the tumor itself was successful in 71% of all malignancies, whereas in only 6.6% of the 76 benign lesions (n = 5) blood flow was found in the central tumor area. In the area surrounding the tumor blood flow was detected in 83% of all carcinomas, but only in 29% of benign findings. Blood flow could be detected significantly higher in malignancies than in benign lesions (p = 0.003). Blood flow detection in the tumor itself was a highly specific (93%) method of discrimination between malignant and benign breast tumors. Further quantification by means of doppler parameters only increases insignificantly specificity, quantification of blood flow in the area surrounding the tumor using the RI and the comparison with the contralateral breast could improve the diagnostic value as our findings RI < 8 for benign vs. > or = 8 for malignant lesions demonstrated. Detection of malignant tumors showed a sensitivity of 80%, a specificity of 90%, and a positive predictive value of 93%. In patients with breast cancer (histologically confirmed) the detection rate of blood flow in tumors and surrounding areas was independent of tumor size or nodal status.

Blood Flow Velocity↗
PubMed1995

Initial results of intraluminal ultrasound in gynecologic diagnosis.

The interior of hollow organs can be examined using extremely small intraluminal ultrasound transducers inserted into catheters. We tested the practicality of this method and the range of indications for which it could be useful in gynecology by performing initial examinations of extirpated uteri and fallopian tubes. In vivo, we inserted an intraluminal unit with transducer diameters of 3.5F and 5F through the cervix into the fallopian tubes of 15 patients during hysteroscopy or laparoscopy. The catheter was inserted successfully into the tube in all 15 women, and in 9 all the way to the distal end. The tubal wall was identified precisely, and a functional diagnosis of tubal motility was established for the first time. However, it was impossible to differentiate between tubal epithelium and muscularis. Also, uterine endometrium cannot be evaluated accurately with the current level of technology. This technique will enable the first functional examination and diagnosis of the tubes and uterus, provided that further improvements can be made in the quality of the images.

Catheterization↗
PubMed1995

[Initial experiences with laparoscopic intraoperative ultrasound].

Preoperative ultrasound as well as intraoperative laparoscopic diagnosis have both their limits, a fact that might be significant for laparoscopic surgical management. In particular, since in this surgical domain, where almost everything has become technically feasible, the operator must decide what is to the benefit of the patient. A possible solution could be laparoscopic ultrasound, i.e. ultrasound diagnosis per laparoscopy at the very site of the lesion. The advantages are evident. Due to the closeness to the organ to be examined, the frequency of the scan head can be extremely high, resulting in better resolution. Also, structures could be visualized by ultrasound which e.g., due to adhesions cannot be seen with the laparoscope. Moreover, ultrasound offers a view into the structures which can be seen only from the exterior with the laparoscope. To perform these examinations we used a specially designed scanhead (Toshiba): Instead of the optical system a crystal array was inserted into a conventional gastroscope. The result was a high resolution 7.5 MHz linear array at the distal end of a freely movable gastroscope. Colour doppler sonography is feasible with this scanhead. We examined 19 patients, 16 of them with ovarian tumours, and attempted visualization of the uterine myometrium/endometrium as well as of the liver. In six cases of ovarian tumours in which only cystic structures were found by preoperative transvaginal sonography, laparoscopic ultrasound additionally revealed solid inner structures. In 5 cases direct laparoscopic view of the ovarian lesions was impossible due to severe adhesions. They were, however, easily detected by intraoperative ultrasound.(ABSTRACT TRUNCATED AT 250 WORDS)

Equipment Design↗
PubMed1995

[Endoscopic colposuspension ("retziusscopy" versus laparoscopy). An effective extension of the surgical spectrum of stress incontinence?].

Within the framework of "minimal access surgery" a prospective randomised study was initiated at the Dept. of Obstetrics and Gynaecology of Heidelberg University to examine the feasibility of endoscopical abdominal Burch colposuspension for stress incontinence (II-III), at laparoscopy and "retziusscopy". Further, also prospectively randomised, two suspension techniques: needle suspension and suspension by means of alloplastic material with stapler fixation, were compared, irrespective of the endoscopic approach chosen, especially because long-term results of our study population on colposuspension with fibrin glue which are now available, are below expectations, worse than those obtained with conventional techniques. Except for a bladder lesion (during laparoscopic dissection of the space of Retzius) no intra- or postoperative complications occurred in the pilot study group of 20 patients. Both types of endoscopic access proved technically feasible, and presented the typical advantages of minimal access surgery such as short hospitalization and rapid recovery. Short-term follow-up (2-12 months) showed subjective and objective results (continence in 18/20 patients), comparable to conventional abdominal procedures at laparotomy. Detailed evaluation of subgroups is not yet possible, since the number of patients it still too small and follow-up too short.

Fasciotomy↗
PubMed1995

[Is co-administration of ethanol to the distension medium in surgical hysteroscopy a screening method to prevent fluid overload? A prospective randomized comparative study of ablative versus non-ablative hysteroscopy and various ethanol concentrations].

OBJECTIVE: Is it possible to diagnose early a beginning fluid absorption during operative hysteroscopy by adding ethanol to the distension medium? METHODS: A prospectively randomised comparative study of ablative versus non-ablative operative hysteroscopy with differing ethanol concentration was performed. Purisole (a mannitol/sorbitol solution) was used as distension medium. RESULTS: The results of the study show that at those hysteroscopical procedures at which the endometrium is not or only minimally injured (e.g. syneciolysis, hysteroscopic proximal tubal catheterisation) an intraoperative screening is not necessary due to the low absorbing amounts. At the hysteroscopical procedures as the resection of myoma, endometriumablation and septumresection, however, an addition of ethanol of 2% to the distension medium has proved to be useful, because with this method absorbing amounts from 400 mls can be established by positive values of breath alcohol. As the result of a further absorption of fluid, but delayed in time compared to the first positive value of breath alcohol, there is an increase of the central venous pressure and a hyponatraemia. CONCLUSION: The intraoperative ethanol-monitoring is a non-invasive procedure which can be performed at ablative-operative hysteroscopies and has no negative influence on the course of the intervention and the general condition of the patients.

Adult↗
PubMed1995

[Experimental microendoscopy of the milk duct system (ductoscopy)].

According to recent reports, the microendoscopic lactiferous duct investigation (ductoscopy) could improve diagnosis in case of pathological nipple discharge. However, the description of a reproducible and reliable methodology, suitable for thorough evaluation of the lactiferous duct is missing so far. Therefore, the pressure study developed a procedure, that may serve now as an experimental basis for further clinical evaluation. Access to the mamillary duct is primarily gained using atraumatic flexible teflon catheters. Corresponding to the diameter of the duct, either a semirigid 0.87 mm fiberendoscope can be successfully introduced via a 1.2 mm catheter, or a flexible 0.50 mm fiberendoscope via a 1.0 mm catheter. A controlled distension using few milliliters of ringer's lactate is the prerequisite for clear visualization of the intraductal space and protection against iatrogenic wall lesions. Metal microtocars are available as prototypes. They carry a somewhat higher risk to perforate, but are advantageous when pointing at an intraductal structure and using the microtrocar as a mark for microdochectomy.

Animals↗
PubMed1995

[Hysteroscopic endometrium ablation in "high-risk" situations and in hemorrhagic diathesis].

A hysteroscopic endometrial ablation (HEA) under maximal anesthesiologic surveillance was performed on 34 high-risk patients (group I: chronic anticoagulant therapy n = 26; group II: endogenous coagulopathy n = 8) with therapy resistant meno-metrorrhagia to avoid a hysterectomy (HE). Total amenorrhea, or a least hypomenorrhea respectively cyclic spotting could be attained primarily in 22 patients (group I: 19; group II: 3), after a repeat procedure in further 6 patients (4 in group I, 2 in group II). Subjective evaluation of surgical results (overall 22 patients primarily satisfied, 6 secondarily) also differed between the two subgroups (group I: p < 0.01 primarily satisfied; p < 0.05 secondarily satisfied vs. p < 0.05 and p < 0.01 in group II). A HE had to be performed on two patients due to extensive adenomyosis uteri interna (group II). The significantly better results in the anticoagulation group were probably due to the basic illness. Larger groups will, however, be necessary before any conclusions from this difference can be drawn. No surgical or anesthesiological complications occurred. There also were no major postoperative complications (1 endomyometritis, 2 cervical stenoses). Endometrial ablation was found to be a valuable treatment alternative for this specific group of patients with severe coagulopathy, thrombo-embolic or thrombotic disease.

Adult↗
PubMed1994

The HysteroTrainer, a simulator for diagnostic and operative hysteroscopy.

Hysteroscopy has become an integral part of operative gynecology, with rates of major complications of 1%. To avoid serious, even lethal, complications, an intensive, well-structured training program for practicing surgeons is necessary. In response to these educational requirements. The HysteroTrainer was developed to provide in vitro simulation training for diagnostic and operative hysteroscopy, including laser and high-frequency electrosurgery.

Cervix Uteri↗
PubMed1994

Operative Hysteroscopy: Results, Security Aspects, In Vitro Simulation Training (Hysterotrainer)

To date, hysteroscopy has become an integral part of the overall gynecologic surgical concept. In 156 women results of intrauterine hysteroscopic surgery are demonstrated to be at least comparable to those of conventional procedures. Moreover, a meta analysis of the literature (n = 10,000) as well as our own experience (n = 200) supports the view that complication rates may be minimized by a well-structured training program which includes the recently developed in vitro simulation trainer, the HysteroTrainer.

Journal Article↗