Biomedical subjects
Publications and source records attributed to T Frede.
Laparoscopic nephropexy is a suitable and clinically established procedure for the treatment of symptomatic nephroptosis. The availability of a minimally invasive therapy can facilitate decisions regarding the indication after careful selection of patients.
HER2 overexpression in breast cancer is associated with a poor prognosis, resistance to endocrine therapy and chemosensitivity to anthracyclines and paclitaxel. Moreover, trastuzumab (Herceptin) shows therapeutic benefit in patients with HER2 overexpressing tumors. Therefore, knowledge of the pretherapeutical HER2 status allows an optimal selection of patients for treatment. In addition to a definitive histological diagnosis, core biopsies of tumors offer the opportunity to evaluate the HER2 status preoperatively. In 64 patients with invasive breast cancer, sections of core biopsies and of the subsequently removed whole tumor were investigated immuno-histochemically with the DAKO HercepTest. Fifteen tumors (23%) revealed HER2 overexpression, and 44 tumors (69%) were negative in both, the core biopsy and the whole tumor sections. Two core biopsies were negative whereas the corresponding final specimen was 2+ positive. In 3 cases weak overexpression was observed in the core biopsy, but the whole tumor was negative. The overall concordance of the results achieved at core biopsy and whole tumor sections was 92% (kappa = 0.8). A negative HER2 result on core biopsy was never associated with a score 3+ tumor specimen nor was there a case of negative whole tumor specimen with a preceding 3+ score in the biopsy. If one demands the highest degree of overexpression (3+), 100% of our study patients would have been selected correctly using the results on core biopsy alone. We thus conclude, that the immunohistochemical investigation of core biopsies offers the opportunity for a valid preoperative estimation of HER2 overexpression.
Ultrasonography was first used as a therapeutic aid in endourology in the early 1970s. Since that time, ultrasound has played an important role, and nowadays, interventional ultrasonography is an established procedure in urology. Procedures on the kidney, bladder, and prostate, which require different puncture techniques, are performed under ultrasound guidance. Today, extracorporeal shockwaves for the treatment of stones and Peyronie's disease are applied under ultrasonic control. Furthermore, high-intensity focused ultrasound (HIFU) is used experimentally for the treatment of renal tumors and, clinically, for the treatment of prostate cancer. In urologic emergencies, diagnostic and interventional ultrasonography is an important tool. Interventional ultrasound in urology has become an outstanding tool for the planning and performance of a variety of procedures, and every urologist should be able to use these technologies.
In urology, at the end of the last millennium, there was an increasing use of computerized technology, extracorporeal shock wave lithotripsy, microwave therapy and high-energy focused ultrasound. However, experience with manipulating robots in urological surgery is still very limited. Laparoscopic surgery is handicapped by a reduction of the range of motion because of the fixed trocar position. The da Vinci system is the first surgical system to address all these problems adequately. The system consists of two main components: the surgeon's viewing and control console with three-dimensional imaging and the surgical arm unit that positions and manoeuvres detachable surgical instruments. The surgeon performs the procedure seated at the console holding specially designed instruments. Telerobotic laparoscopic radical prostatectomy provides advantages such as stereovision, dexterity and tremor filtering, but there is a learning curve with the device, mainly because of the magnification, the three-dimensional image and the lack of tactile feedback. However, after only a short period of time, the experienced surgeon is able to become familiar with the device. The impact of robotics in urological surgery is therefore very promising, and we are convinced that it will totally change the future of urological surgery.
INTRODUCTION: In 1999, Guillonneau and Vallancien presented a refined approach of a descending laparoscopic radical prostatectomy which based mainly on the primary access to the seminal vesicles and an improved suturing and knotting technique. Based on our own experience reconstructive laparoscopy as well as with open retropubic radical prostatectomy we have used a combined ascending/descending technique similar to open surgery. In this paper we want to describe our approach and to present the initial results with the Heilbronn technique. MATERIALS AND METHODS: A transperitoneal approach is used with a W-shaped arrangement of the trocars (13-mm umbilical port, 2 x 10 mm medial, 2 x 5 mm lateral ports). After the exposure of the Retzius' space and control of the dorsal vein complex the urethra is incised and the distal pedicles of the prostate (+/- the neurovascular bundle) are transsected. We now pull the apex ventrally and start with the incision at the bladder neck followed by a transvesical access to both vasa deferentia and seminal vesicles. The gland is entrapped in the Extraction Bag. After accomplishing the posterior wall of the urethrovesical anastomosis with five interrupted sutures, the foley catheter is placed into the bladder and the bladder neck is closed. Now the prostate is extracted via the umbilical incision. From March 1999 to June 2000, we have performed 100 cases (48 pT2-, 47 pT3- and 5 pT4 tumors). The mean preoperative PSA was 26.8 (1.4-75.5) ng/ml. Two tumors were grade 1, 72 grade 2 and 26 grade 3. Median Gleason score was 6 (3-9). All specimen were inked and examined according to the Stanford protocol. Postoperative continence was evaluated using a questionnaire monitored by a colleague who was involved in surgery. RESULTS: We had 5 conversions (rectal injury, difficult dissection, adhesion, 2x bleeding at the dorsal vein complex). The mean operating time was 278 (180-500) min., the transfusion rate 31%. One patient required reintervention due to bleeding from the right obturator fossa. 95% of the patients did not require any analgesia on the second postoperative day. Positive margins were found in 17% of the patients, of which 12 had a PSA nadir to a value of less than 0.1 ng/ml within 3 weeks after surgery. In 82 patients, the anastomosis was tight after removal of the catheter, median catheter time was 8 (6-30) days. 4% developed a stricture at the anastomotic site which could be treated by laser incision. On discharge 33% were continent, after 6 months 81%, whereas only 2 patients still suffer from grade II stress incontinence at 9 months. CONCLUSIONS: Laparoscopic radical prostatectomy is feasible but requires laparoscopic expertise. Its learning curve is still ongoing. Morbidity is low, oncological control is similar to results of open surgery, functional results are promising.
INTRODUCTION: Telepresence surgery offers theoretically to overcome two main problems of laparoscopic surgery, i.e. the limitation to only four degrees of freedom and the lack of stereovision. Since 1998, telesurgical minimally invasive procedures have been performed with the da Vinci system mainly for cardiac bypass surgery. Clinical experience in urology is still very limited. We want to present our initial experience using the device for robot-assisted laparoscopic radical prostatectomy. MATERIAL AND METHODS: The Intuitive surgical system consists of two main components: the surgeon's viewing and control console with 3D imaging and the surgical arm unit that positions and maneuvers detachable surgical instruments. These instruments introduced via two 8-mm trocars allow movements in all 6 degrees of freedom due to the EndoWrist technology. The surgeon performs the procedure seated at the console holding specially designed instruments. Highly specialized computer software and mechanics transfer the surgeon's hand movements exactly to the microsurgical movements of the manipulators at the operative site. We have used a semilunar-shaped 5-trocar arrangement with the robot's arms at the lateral trocars and two assistant trocars medially. A sixth trocar was used in the right suprapubic area for retraction of the gland. The left assistant used different instruments such as bipolar forceps, Ultracision, Endoclip, whereas the right assistant mainly used the suction-irrigation device. Except the first case, the Intuitive System was attached after exposure of Retzius' space. RESULTS: We have treated 6 patients (2 pT2, 4 pT3, median Gleason score 6). The OR time averaged 315 (242-480) min including pelvic lymph node dissection. No intraoperative complications occurred, 1 patient required transfusions. There were no positive margins, median catheter time was 5 days. 3 patients were completely continent after 1 month. CONCLUSION: Telerobotic laparoscopic surgery offers several advantages over all presently available techniques, such as all six degrees of freedom, dexterity enhancement, tremor filtering, and stereovision. There is a learning curve with the device, mainly because of the magnification, the 3D image and the lack of tactile feedback. However, only after a short period of time, the experienced surgeon is able to get familiar with the device. However, there are still concerns with respect to the high investment and running costs of the device as well as regarding the necessity of further developments of instruments for urological procedures.
BACKGROUND: The difficulties of minimally invasive reconstructive surgery, laparoscopically or retroperitoneoscopically, are caused by spatial limitation and fixed trocar positions and, therefore, restricted movement and handling of the instruments. In addition to a standardization of the technique, continual training, and improved instrument technologies, optimization of the geometry of reconstructive surgery, such as angles and distances between the working ports or the camera and needle position, are imperative to providing an optimal clinical performance. MATERIALS AND METHODS: After designing a standardized suturing technique and conducting an experimental analysis of the geometric factors important in reconstructive surgery, we transferred these results to our clinical setting. A series of 116 reconstructive laparoscopic and retroperitoneoscopic procedures (nephropexy, pyeloplasty, bladder neck suspension, and radical prostatectomy) were analyzed according to the technical realization and quality of reconstruction. Trocar and table positions were adjusted according to our preliminary results, as were the position of the instruments and camera. RESULTS: The trocar and instrument positions are critical for the clinical outcome of reconstructive surgery. Continual training in a standardized suturing technique, together with the clinical application of the important geometric rules, can reduce surgery time by 50%. The time required for suturing single knots could be decreased even more: as much as 75%, thus ensuring efficient and safe reconstructive surgery. CONCLUSION: Reconstructive procedures such as pyeloplasty or radical prostatectomy can be standardized and performed in an acceptable amount of time with adequate quality when adhering to a standardized technique and the important geometric rules. Improved performance in terms of time and quality will increase the acceptance of these procedures, which can help to solve the problem associated with a low total number of indications for laparoscopy and retroperitoneoscopy.
OBJECTIVES: We describe our experience with laparoscopic retroperitoneal lymphadenectomy (LRLA) in 34 patients with low-stage germ cell tumors treated from 1992 to 1998. All patients had clinical stage-I disease with no clinical evidence (CT scan, ultrasound, tumor markers) of metastases. A laparoscopic dissection was used to assess the pathologic status of the relevant retroperitoneal lymph nodes. MATERIAL AND METHODS: 17 patients were treated by a transperitoneal laparoscopic approach, whereas in the last 17 patients retroperitoneoscopic retroperitoneal lymph node dissection was performed. The lymph node dissection was performed identically to open surgery with the modified template according to Weissbach including the paracaval, interaortocaval, upper pre-aortic, and right common iliac zonal nodes for right-sided tumors, and para-aortic, upper pre-aortic zones for left-sided tumors. Retrieval of the lymph node chains was accomplished using a small organ bag. RESULTS: The procedure could be completed successfully in 30 of 34 patients with stage-I disease. In these cases the mean duration of the procedure was 248 min. In 3 patients the lymphadenectomy was abandoned, because frozen section showed metastasis. In 1 case conversion to open surgery was necessary because of bleeding from the aorta. One patient developed a delayed ureteral stenosis which required operative repair. Three patients required temporary insertion of an indwelling ureteral stent, and another patient had a pulmonary embolism with an uneventful outcome. One patient with a LRLA on the right side later developed retrograde ejaculation. In 6 of the 33 patients (18%) embryonal carcinoma or mixed carcinoma was found. The postoperative hospital stay averaged 5.3 (3-9) days for the patients without complications or conversion to open surgery. After a median follow-up of 40 months no regional relapse occurred, but 2 patients developed pulmonary metastases which were treated successfully by three cycles of platinum-based chemotherapy. All patients have no evidence of disease. CONCLUSIONS: Our experience suggests that LRLA is a safe and accurate method for low-stage germ cell tumors with minimal invasiveness, but because of its technical difficulty it should be restricted to experienced centers.
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BACKGROUND: Spatial limitation, together with a fixed trocar position, restricted handling, and movement of the instruments, is inevitably associated with reconstructive laparoscopy and retroperitoneoscopy. This problem includes not only suturing technique and instruments but also geometric factors of endoscopic reconstruction, such as optimal distances between the working trocars, length of instruments, and angles between the instruments and the object. We present an experimental access to determine the specific impact of these factors on reconstructive laparoscopy. MATERIALS AND METHODS: In an in vitro model, end-to-end anastomoses of porcine intestine were performed using a standardized intracorporeal suturing technique. Suturing was performed without and after training in reconstructive surgery with variation of the following geometric factors: (1) the distance between the working trocars (between 6 and 12 cm); (2) the position of the object (lateral right, medially, lateral left); (3) the camera position (medially, lateral right, lateral left); (4) the angle between the instruments and a horizontal line (15 degrees , 55 degrees, 90 degrees); (5) the intracorporeal length of instruments (between 10 and 25 cm); and (6) narrowed space available for the instruments (between 4 and 25 cm). RESULTS: Continual training decreased the time required for suturing between 30% to 50%. Training decreased the time required for nonsuturing activities between 50% and 70% but the time required for suturing activities only between 20% and 45%. If the space between instruments and camera was limited, shifting the camera into a lateral position simplified the procedure of intracorporeal suturing. Angles of <55 degrees between instruments and the horizontal line simplified laparoscopic suturing, as did angles of <45 degrees between the instruments. In cases of maximally narrowed space (diameter of 4 cm), a suture filament length of <10 cm decreased the time required by 30%. CONCLUSION: We suggest an isosceles triangle between the instruments with an angle between 25 degrees and 45 degrees and an angle of <55 degrees between the instruments and the horizontal line as the optimal geometry for intracorporeal suturing. These data should be considered when planning a reconstructive laparoscopic procedure (i.e., alignment of trocars, table position). However, further studies are required to confirm these preliminary results.
BACKGROUND: Peyronie's disease is an idiopathic disorder of the penis that produces erectile dysfunction. It affects mainly the tunica albuginea. We describe our preliminary results with extracorporal shockwave therapy (ESWT) as a new noninvasive modality for the treatment of Peyronie's disease. PATIENTS AND METHODS: In this study, 24 patients aged 36 to 67 years were treated with ESWT on the Lithostar overhead-module (Siemens). All our patients had unsuccessful medical treatment before ESWT. The average plaque was 7x15 mm. The number of shockwaves ranged from 15,000 to 25,000 (18-21 kV) delivered in four to ten sessions. Most patients needed local anesthesia before therapy. RESULTS: Four patients (17%) showed marked improvement and complete remission of the penile deviation. Six patients (25%) showed partial remission with painless erections after treatment. Four patients had painless erections after treatment but still had some penile deviation. In 10 patients (41%), ESWT failed, necessitating subsequent penile surgery. CONCLUSIONS: Our preliminary results with a response rate of 59% with ESWT for Peyronie's disease, including a 17% complete remission rate, is encouraging. However, further multicenter studies will have to prove if ESWT is a real therapeutic option for this disease.
PURPOSE: The 4 most active centers of the laparoscopy working group of the German Urologic Association collected data about the complications associated with laparoscopic surgery in urology. MATERIALS AND METHODS: At 4 centers 2,407 laparoscopies or retroperitoneoscopies were performed as of May 1998, including 776 for varicocelectomy, 259 for cryptorchidism, 481 for pelvic lymph node dissection, 351 for nephrectomy/heminephrectomy renal pathology, 139 for renal cyst resection, 58 for ureteral procedures, 44 for adrenalectomy, 41 for nephropexy, 41 for lymphocele fenestration, 40 for retroperitoneal para-aortic lymphadenectomy and 187 for other operations. The complications were evaluated, listed according to the anatomical specificity and grouped with respect to the surgical step during laparoscopy. RESULTS: A total of 107 complications (4.4%) occurred. The re-intervention rate was 0.8% and the mortality rate was 0.08%. The complication rate depended on the difficulty of the procedure and averaged 1.0, 3.9 and 9.2%, respectively, for easy, difficult and very difficult operations. The majority were vascular injuries (1.7%) and visceral lesions (1.1%) followed by complications of healing and infection (0.8%). Only 0.2% of complications was associated with the access technique (trocar insertion), whereas most occurred during dissection (2.9%). The complication rate was 13.3% for the first 100 procedures and subsequently averaged 3.6%. CONCLUSIONS: Critical documentation of experience from several institutions, especially for an analysis of complications of urological laparoscopy, is important for the development of this surgical technique. The overall complication rate is comparable to other specialties. Future technical developments in trocar insertion, tissue dissection and control of bleeding with our improved training program will further reduce the complication rate.
UNLABELLED: A retroperitoneal access is most commonly applied for open procedures in urology. With introduction of the balloon dissecting technique, this anatomical route could also be used for laparoscopic surgery. MATERIALS AND METHODS: From 12/1992 to 10/1997, a total of 200 retroperitoneoscopic procedures have been performed in 197 patients (age 4-82 years): 78 nephrectomies, 50 renal cyst resections, 14 nephropexies, 11 ureterolyses, 8 retroperitoneal lymph-node dissections, 8 renal biopsies, 6 adrenalectomies, 6 heminephrectomies, 6 pyeloplasties, 5 ureterolithotomies, 6 ureterocutaneostomies and 2 others. Thirty-eight patients (19%) had undergone previous abdominal surgery; 22 (11%) had had kidney and ureter operations. Dissection of the retroperitoneal space was done with a balloon catheter in 14 or a balloon trocar system in 93 cases, and in the last 93 patients digital dissection with the index finger proved to be sufficient. RESULTS: We classified 76 as simple (i.e., renal biopsy, renal cyst resections, ureterocutaneostomy) and 102 as difficult (i.e. adrenalectomy, nephrectomy, nephropexy) and 22 (11%) as very difficult operations (i.e., pyeloplasty, heminephrectomy, lymphadenectomy). There has been a significant learning curve during the first 50 cases as reflected by increased operating time and complications and the conversion rate to open surgery. After that, the OR times mainly depended on the difficulty of the procedure, averaging 45-100 min for an easy retroperitoneoscopy, 95-185 min for a difficult and 185-240 min for a very difficult operation. In the last 50 cases, the complications, conversion and reintervention rate have become comparable to open surgery (2, 4 and 2%). CONCLUSIONS: After more than 200 cases of retroperitoneoscopy, the access technique has been significantly simplified. The procedure is standardized, safe and reproducible.
The aim of this pilot study in 54 patients was to improve the visualization of the anatomy and postoperative changes in the pelvic topography after bilateral ureteroileal urethrostomy, using surface rendering of electron beam CT (EBCT) data for the 3D display. Fifty-four patients (39 men and 15 women) were scanned with an EBCT unit between 3 and 110 months after performing orthotopic ureteroileal urethrostomy ("Hemi-Kock") or ureteroileal rectosigmoidostomy. Various parameters and spatial viewing points were used in the 3D reconstruction, which was performed interactively on external workstations with commercially available software. The anti-reflux nipple was visualized as a distinct structure in all patients. In 8 patients with an interval of more than 12 months between surgery and CT, the pouch had developed an ovoid shape almost indistinguishable from the original bladder. The segmented data sets were partly animated to display the anatomy as virtual endoscopy. Three-dimensional depiction and virtual endoscopy of the neobladder using EBCT are a new way of imaging the postoperative anatomy. Its clinical efficacy in the diagnosis of inconclusive postoperative morbidity, especially voiding problems, and planning of necessary therapy have to be the subject of further evaluation.
PURPOSE: A retroperitoneal access is commonly used for open urological procedures. Since the introduction of the balloon dissecting technique by Gaur this anatomical route has also been used for laparoscopic surgery. We present our experience with retroperitoneoscopy in 200 cases. MATERIALS AND METHODS: From December 1992 to October 1997 a total of 200 retroperitoneoscopic procedures were performed in 197 patients 4 to 82 years old, comprising 78 nephrectomies, 50 renal cyst resections, 14 nephropexies, 11 ureterolyses, 8 retroperitoneal lymph node dissections, 8 renal biopsies, 6 adrenalectomies, 6 heminephrectomies, 6 pyeloplasties, 5 ureterolithotomies, 6 ureterocutaneostomies and 2 others. Of the patients 38 (19%) and 22 (11%) had undergone previous abdominal surgery, and kidney and ureter operations, respectively. Dissection of the retroperitoneal space was enabled by the use of a balloon catheter in 14, balloon trocar system in 93 and finger dissection technique in 93 cases. RESULTS: We classified 76 procedures (38%) as simple (renal biopsy, renal cyst resections, ureterocutaneostomy), 102 (51%) as difficult (adrenalectomy, nephrectomy, nephropexy) and 22 (11%) as very difficult (pyeloplasty, heminephrectomy, lymphadenectomy). There was a significant learning curve during the first 50 cases reflected by longer operating time, and higher complication, conversion to open surgery and open reintervention rates (14, 10 and 6%, respectively). In addition to the learning curve, mean operating time depended on the difficulty of the procedure, averaging 45 to 100 minutes for a simple, 95 to 185 for a difficult and 185 to 240 for a very difficult retroperitoneoscopy. In the last 50 cases the complication, conversion and reintervention rates (2, 4 and 2%, respectively) were acceptable for routine clinical application. CONCLUSIONS: After experience with more than 200 cases of retroperitoneoscopy the access technique has been significantly simplified. The procedure is standardized, safe and reproducible.
Laparoscopic or retroperitoneoscopic interventions such as nephrectomy or tumor nephrectomy call for the removal of large quantities of tissue, which can no longer be extracted via the relatively confined lumen of a cannula. For this purpose, a variety of organ retrieval systems have been designed and are commercially available with the aim of safe tissue retrieval. This paper summarizes the results of an experimental and clinical comparison of the most important organ entrapment systems suitable for endoscopic nephrectomy. The LapSacs was the first organ bag especially designed for laparoscopic nephrectomy. Despite various new modifications of this entrapment system, it still represents one of the best alternatives and has been used worldwide with success. However, because of its simplicity, it requires a certain laparoscopic expertise and involves a learning curve. Newly developed retrieval systems (i.e., LapBag, Extraction Bag, Endo-Catch) offer some advantages regarding the handling of the bag, which may be particularly useful during retroperitoneoscopic nephrectomy with a restricted working space. Retrieval systems (i.e., Endobag, Endopouch) with low resistance to tearing forces or permeability to tumor cells or bacteria (i.e., Espiner Bag) cannot be recommended for endoscopic nephrectomy.
Endoscopic pyelotomy is a minimally invasive procedure that is increasingly used for the management of ureteropelvic junction (UPJ) obstruction. We report the results and advantages in the management of UPJ obstruction using a ureteroscopic retrograde laser-assisted approach (laser endopyelotomy; LEP). Thirty-four patients were treated between December 1994 and June 1997 by this new technique. Twenty-seven obstructions were primary. The mean time of follow-up is 18 months. An indwelling ureteral catheter was placed 3 weeks prior to treatment. Intraoperatively, after the removal of the stent, a guidewire was passed across the stenosis, and the ureter was entered with a semirigid ureteroscope. The LEP was then performed under visual control using a contact laser fiber until all obstructive fibers had been cut. Follow-up examinations included sonography, intravenous urography, and, in unclear cases, a radionuclide renal scan with furosemide application after 3 months. The success rate was 85%. The most important factor influencing the outcome was the grade of hydronephrosis. Postoperative side effects have been minimal, and minor complications occurred in only 5 patients (15%). Laser endopyelotomy is a minimally invasive procedure with less morbidity for the treatment of UPJ obstruction. Only patients with a severe extrinsic cause of obstruction should be excluded from this technique. These cases can be approached laparoscopically.
OBJECTIVES: Different techniques have been introduced to perform laparoscopic nephrectomy using either the transperitoneal or the retroperitoneal route. However, to date only few data exist comparing the results and morbidity of these procedures as well as with the standard technique of open nephrectomy. MATERIAL AND METHODS: This paper compares the clinical results of 18 transperitoneal laparoscopic nephrectomies (TLN) for benign renal disease with 17 retroperitoneal laparoscopic nephrectomies (RLN) and 19 consecutive open nephrectomies (Nx). All groups were comparable in terms of indication. The analysis of clinical data included operative time, morbidity, length of analgesic use and postoperative hospital stay. RESULTS: The mean operative time for benign disease was 206.5 for TLN, 211.2 for RLN and 117 min for open nephrectomy. Analgesic medication requirement per patient was 2 days for TLN, 1 day for RLN and 4 days for Nx while the postoperative hospital stay averaged 7 days for TLN, 6 days for RLN and 10 days for Nx. The time of convalescence was 21 days after RLN, 24 days after TLN versus 40 days after open nephrectomy. CONCLUSIONS: Our results demonstrate an overall clear advantage of a laparoscopic approach when compared to open surgery and also reveals distinct benefits of a retroperitoneal approach.