A new measure to assess the difficulty of liver resection.

BACKGROUND: There is no valid measure to assess surgical difficulty and feasibility of a planned liver resection. It is the objective of this study to evaluate a mathematical measure from a 3D graphical analysis. METHODS: Eleven different 3D models of hepatic tumours were evaluated by experts for resectability and analysed with Amira graphic software taking into consideration the portal and hepatic venous vascular relationships. Virtual resection volumes with increasing resection margins from 1 to 30 mm were determined separately for portal veins, hepatic veins, their intersections and volume unions. The integral of the increasing resection volumes was defined as risk coefficient. The risk coefficients from this volumetric analysis were compared with the expert opinion. RESULTS: The risk coefficient based on the integral of portal venous and hepatic venous volume unions reproduced the expert opinion highly significantly (correlation coefficient 0.9, p<0.05) and more accurately than volumetric analysis of the planned resection margin. CONCLUSION: With automated volumetric analysis, anatomically problematic situations in liver surgery can be reproduced and scaled. The risk coefficient obtained is a suitable objective measure for defining risk areas in liver surgery.

Development and validation of a three dimensional ultrasound based navigation system for tumor resection.

BACKGROUND: Intraoperative navigation is a rapidly emerging procedure in orthopaedic surgery and neurosurgery. For abdominal tumors (e.g. liver metastasis) and soft tissue tumors there is only limited experience with navigation techniques due to problems of organ shift and tissue deformation. We have developed a navigation system for tumor resection in soft tissue based on 3D ultrasound imaging and optical tracking. METHODS: Two different modes of navigation were evaluated and compared with conventional surgery in an experimental soft tissue model. Both techniques were based on 3D ultrasound and an optical tracking system for intraoperative real time registration of surgical instruments. These two techniques were used: a) Indirect navigation with ultrasound guided insertion of a tracked hook needle into the tumor; and b) Direct navigation using a 3D image which was obtained with an optically tracked 3D ultrasound probe. It was the aim of both techniques to achieve a circumferential resection margin of 2cm around the tumor. RESULTS: A total of 23 resections were performed consisting of indirect (n=7) and direct (n=10) navigation and conventional surgery (n=6) as gold standard. For indirect navigation a median deviation from the ideal resection margin (accuracy) of 0.32cm was measured. Direct navigation showed an accuracy of 0.16cm compared to 0.42cm with conventional surgery. Navigated surgery showed for both techniques a significant increase of resection accuracy compared to conventional resection (p<0.05). CONCLUSION: 3D ultrasound based indirect and direct optoelectronic navigation for resection of soft tissue tumors is feasible and may improve intraoperative orientation with increased surgical precision.

Image-guided surgery of liver metastases by three-dimensional ultrasound-based optoelectronic navigation.

BACKGROUND: Vessel-oriented surgery and tumour-free resection margins are essential for resection of liver metastases to preserve liver parenchyma and improve oncological outcome. Preoperative three-dimensional models reconstructed from imaging data could facilitate surgical planning with the use of navigation technology. METHODS: Thirty-three patients with central and/or impalpable liver metastases were scheduled for navigated hepatic resection. Intraoperative three-dimensional ultrasonography and an infrared-based optical tracking system were used for data registration and image-guided surgery. Postoperative three-dimensional data were compared with the preoperative virtual surgical plan to assess the accuracy of navigation, and clinical results were compared with those of a matched control group of 32 patients. RESULTS: Navigation was successful in 32 of 33 patients. Realization of the preoperative plan and R0 resection was achieved in 30 of these 32 patients. The median discrepancy between the planned and actual vascular dissection level was 6 (range 0-11) mm. There was a reduced rate of R1 resection in the navigated group compared with the control group (two versus four patients), and more parenchyma was preserved. CONCLUSION: Three-dimensional ultrasound-based optoelectronic navigation technology improves intraoperative orientation and enables parenchyma-preserving surgery with high precision.

[Significance of palliative resection of gastrointestinal tumors]. / Hat die palliative Resektion bei gastrointestinalen Tumoren noch einen Stellenwert?

Before any palliative tumor resection, the morbidity and mortality risks must be carefully weighed against the continued prognosis (including quick and lasting relief of discomfort from the tumor) and alternative strategies such as bypass, chemotherapy, and radiotherapy. Multimodal concepts have seen considerable progress in recent years, and endoscopic and interventional methods have expanded the instrumentarium for palliative tumor therapy. Thus the value of palliative resection must be reassessed. The most important criteria and study results are described here, as they have resulted in increased interest in palliative tumor resection within a multimodal treatment for most gastrointestinal tumors. More studies are needed to learn how much can realistically be expected of these new approaches.

[Minimally-invasive management of common bile duct stones]. / Die minimal-invasive Sanierung der Choledocholithiasis.

Common bile duct stones may present a health hazard for our patients. Nevertheless, since the implementation of laparoscopic cholecystectomy optimal diagnostic and therapeutic algorithm are not yet defined. Symptomatic calculi can be assumed on the basis of pathological laboratory values or diagnosed by means of ultrasound, Intraoperative Cholangiography (IOC) or Magnetic-Resonance-Cholangio-Tomography (MRCT). For therapy of common bile duct stones endoscopic and laparoscopic minimally-invasive strategies are available. As any type of management may show some benefit, it is not yet evident which policy we should prefer. Specialists do not agree on the necessity of therapy in asymptomatic patients with common bile duct calculi at all. This article shows a current state of the opinion and art and tends to highlight trends and future perspectives.

Laparoscopic management of common bile duct stones.

BACKGROUND: While laparoscopic cholecystectomy is widely accepted for therapy of cholecystolithiasis, controversy still exists concerning the management of common bile duct stones. Besides preoperative endoscopic papillotomy followed by laparoscopic cholecystectomy and open common bile duct surgery, management of common bile duct stones can be conducted by laparoscopy, if respective experience is available. METHOD: During laparoscopic cholecystectomy a cholangiography via the cystic duct is routinely performed. If bile duct stones are detected they are retrieved via the cystic duct or via incision of the common bile duct by insertion of a Fogarty catheter or Dormia basket. Exclusion criteria against simultaneous laparoscopic management include suspicion of malignancy, severe pancreatitis, or cholangitis. RESULTS: From November 1991 to March 2002, 200 patients primarily underwent laparoscopic therapy of bile duct stones. Retrieval was performed via cystic duct and common bile duct incision in 115 and 85 cases, respectively. Complete removal was achieved in 91%; complication rate and mortality was 7% and 0.5%, respectively. During the same period primary endoscopic papillotomy was necessary in 40 patients because of the above contraindications. CONCLUSIONS: When correct indications and surgical expertise are observed, simultaneous laparoscopic management of common bile duct stones represents a safe and minimally invasive alternative to a two-procedure approach.

[Minimally invasive surgery (MIC) in the area of the colon and rectum: technique of minimally invasive colorectal surgery]. / Minimal-invasive Chirurgie (MIC) im Bereich Colon und Rectum: Technik der minimal-invasiven colorectalen Chirurgie.

Minimally invasive surgery is gaining increased importance in colorectal surgery. Since 1993 we have performed 378 minimally invasive colorectal procedures (appendzcetomy excluded): right-sided (n = 70) and left-sided (n = 160) hemicolectomy, anterior rectal resections (n = 72), and colostomy (n = 12), Hartmann procedure (n = 17), take-down operation (n = 25), rectopexy (n = 21) and coloproctomucosectomy (n = 2). The indications were diverticulitis (n = 147), benign tumor (n = 40), malignant tumor (n = 135), rectal prolapse (n = 21), Crohn's disease (n = 8), intestinal diversion (n = 25), colonic perforation (n = 2). Postoperative complications were observed in 21% of cases; anastomotic leak developed in 4%; mortality was 0.5%. In keeping with the current literature our data show that in the majority of cases surgical therapy of colorectal disease can be performed in minimally invasive fashion.

Laparoscopic appendectomy does not change the incidence of postoperative infectious complications.

BACKGROUND: It is not clear whether the laparoscopic approach does decrease the incidence of postoperative infectious complications after appendectomy. METHODS: One hundred sixty-nine patients were randomized, 87 with laparoscopic (LA) and 82 with open appendectomy (OA). Patients in the OA group had a McBurney incision; LA was performed in the lithotomy position. RESULTS: Acute appendicitis was confirmed in 75% of patients. The appendix was perforated in 5 patients of the LA versus 2 patients of the OA group. No conversion to the open procedure was necessary. The median operating time was 35 minutes in the LA group and 31 minutes in the open group (P = 0.58). The median postoperative hospital stay was shorter after laparoscopic than after open surgery (3 days versus 4 days, P = 0.026), whereas the time required for return to work was not significantly different (14 versus 15 days). There were 5 (6%) patients with superficial wound infection following LA and 6 (7%) after OA (P = 0.67). Intra-abdominal fluid collections were found in 2 (2%) patients following LA and 3 (4%) patients following OA (P = 0.60). In the LA group, 3 patients presented with intra-abdominal hemorrhage and another 3 developed a paralytic ileus that was treated conservatively. CONCLUSIONS: Laparoscopic appendectomy is as safe and as effective as the open procedure; however, it does not decrease the rate of postoperative infectious complications.

Communication with the elderly psychiatric outpatient.

Elderly psychiatric patients pose special challenges to effective communication. Psychiatric diagnosis relies heavily on verbal communication and can become a casualty in this process. Consequences of an incomplete or distorted data base include inappropriate treatment and polypharmacy. The authors examine the causes of doctor-patient miscommunication and, propose specific, simple measures to improve information exchange for both initial evaluation and follow-up of the geropsychiatric patient.

[Role of the pulsatile organ perfusion surgical simulator in surgery education]. / Die Rolle des POP-Operationssimulators in der chirurgischen Ausbildung.

The operation simulator with pulsatile organ perfusion ("POP trainer") simulates the blood supply of organs or organ complexes and was developed for the training in both minimally invasive and conventional surgery. With the redesigned new POP-trainer, even complex operations, such as colorectal and antireflux procedures can be practised. Due to perfect quality of simulation, simple handling and economic aspects, the POP trainer serves to intensify the training of surgeons, simultaneously decreasing the number of animal experiments.

[Double balloon catheter for facilitating (laparoscopic) choledochus drainage]. / Doppelballonkatheter zur Erleichterung der (laparoskopischen) Choledochusdrainage.

In laparoscopic management of choledocholithiasis the drains available for bile-duct drainage are problematic. Since November 1991 we have given priority to the laparoscopic management of common bile-duct stones (n = 97). In cooperation with industry (W. Rüsch/D-Waiblingen), we have developed a double-balloon catheter for laparoscopic application. In 15 cases we used this double-balloon catheter. There were no complications like dislocation, obstruction or leakage. This new catheter facilitates the procedure of laparoscopic bile-duct exploration in choledocholithiasis. The operating time is reduced and removal of residual concrements is easily possible.

[Laparoscopic versus conventional appendectomy: a prospective randomized study]. / Laparoskopische versus konventionelle Appendektomie: eine prospektive, randomisierte Studie.

The discussion about laparoscopic appendectomy has increased since the introduction of this method. Randomized comparisons are still feasible, whereas this cannot be stated for other laparoscopic procedures (e.g., laparoscopic cholecystectomy). This randomized controlled trial included 170 patients. Open appendectomy was employed in 83 patients, and 87 were treated laparoscopically. The treatment groups were comparable regarding age, sex, Broca index, ASA classification, preliminary operations, and preoperative leucocytes. No statistically significant differences could be found with respect to surgical and general complications, operating time, consumption of analgesics and antibiotics, and return to work. The analysis revealed a statistically significant shorter hospital stay, a shorter time until return to normal physical activity, and a shorter duration of complaints for the laparoscopic group. We were unable to demonstrate any statistically significant advantage in using the open procedure.

[Laparoscopic therapy of choledocholithiasis]. / Die laparoskopische Therapie der Choledocholithiasis.

The introduction of laparoscopic cholecystectomy has led to controversial discussions about the proceeding in case of coincident common bile duct stones. In our unit choledocholithiasis has been treated laparoscopically since November 1991. Basic requirement has been a routine intraoperative cholangiography. 67 patients with common bile duct stones were treated until January 1995. All patients underwent a follow up and the results were compared to other concepts. In 40 cases common bile duct stones were eliminated via cystic duct and in 27 cases by choledochotomy. The choledochus was drained routinely for postoperative x-ray control. In 9 cases we found residual concrements: 7 patients required postoperative endoscopic papillotomy and in 2 cases the calculi where eliminated with a dormia basket introduced via drainage tube. In one case surgical management was changed to laparotomy. Postoperative complications occurred in 8 cases. One patient suffering from bacterial peritonitis underwent laparotomy on the 9th postoperative day; one with bleeding from the cystic artery was treated by relaparoscopy. One patient developed a liver abscess and two patients a bilioma requiring ultrasound guided drainage. A superficial wound infection in one patient and a biliary leakage after removal of the drainage in two patients healed spontaneously. Due to an intact papilla with less stress to the patient, as well as a complication rate comparable with other published therapeutic concepts, this strategy can be recommended as a valuable alternative procedure.

Male breast cancer: Austrian experience.

Data were collected on 169 men treated for breast cancer at 36 surgical departments in Austria between 1970 and 1991. We report here several of their clinical features and assess the importance of established prognostic factors. After a median observation period of 51 months 60 patients (35%) suffered a recurrence. The estimated 5-year recurrence-free survival for the entire group was 55%, and the estimated 5-year overall survival was 62%. Although stage-adjusted data are comparable to those for female breast cancer, the outcome in this series may be attributed to a relatively high frequency of advanced tumor stages. Tumor size (recurrence-free survival p = 0.00001; overall survival p = 0.03) and axillary lymph node status (recurrence-free survival p = 0.0001; overall survival p = 0.0001) proved to have a prognostic impact. Using a multivariate analysis, axillary lymph node status (recurrence-free survival p = 0.001; overall survival p = 0.01) still had prognostic influence. The various procedures used had no effect on local recurrence.

[Educational opportunities in minimally invasive surgery]. / Ausbildungsmöglichkeiten in minimal invasiver Chirurgie.

Since minimally invasive surgery makes high demands on the skill, concentration and endurance of the surgeon, requisite training in this operating technique is of overriding importance. Basic training on pelvitrainers serves to enable the participant to become acquainted with the instruments and the video technique and to gain experience in handling the camera. A realistic simulation of intraoperative situations is not possible. With pulsatile organ perfusion (POP) nearly all abdominal, thoracic, vascular, urological and gynecological surgical procedures, as well as the encountered complications, can be imitated, widely replacing the need for animal experiments. Complex operations which are bound to anatomical structures, have to be practised on anaesthetized animals, as before.

[Laparoscopic therapy of choledocholithiasis]. / Laparoskopische Therapie der Choledocholithiasis.

In the period November 1991 to October 1993 altogether 418 patients underwent laparoscopic cholecystectomy in our unit. Routine intraoperative cholangiography, a prerequisite for diagnosing choledocholithiasis, was successful in 99.3% of cases. 38 patients were found to have common bile duct calculi and their management and follow up are reported in this study. In 36 cases stones were successfully eliminated by means of the laparoscopic procedure, via the cystic duct in 22 cases and by choledochotomy in 14 cases. One patient required postoperative endoscopic papillotomy, and in the remaining case surgical management was changed to classical laparotomy and open choledochotomy. Postoperative complications occurred in five cases. One patient suffering from bacterial peritonitis underwent laparotomy on the 9th postoperative day, another with postoperative bleeding from the cystic artery was relaparoscopied on the same day as the minimal invasive procedure. One patient developed a liver abscess three weeks after operation, requiring drainage with the aid of ultrasound. A superficial wound infection in one patient and biliary leakage after removal of the T-tube in another patient both healed spontaneously. Our results are similar to those obtained with other therapeutic concepts. Because the papilla of Vater remains intract in minimal invasive surgery, which causes relatively little stress to the patient, as well as considering the economic advantages of a single-step procedure, this management strategy can be recommended as a valuable alternative procedure.

Epithelial misplacement after biopsy of colorectal adenomas.

The question has been raised as to whether the removal of biopsy material from colorectal adenomas can lead to misplacement of tumour fragments into the deeper layers of the bowel wall. We carried out an analysis of histological sections obtained from 21 patients in whom, between 2 and 21 days before removal of their adenoma, forceps biopsy (n = 18), or polypectomy (n = 3) had been performed. The initial histological picture a few days after biopsy is of an ulcer covered by a suppurative exudate and abundant mucus-containing small, free-lying groups of tumour cells. After an average of 7 days, we found misplacement of these groups of cells into the submucosa where, during the course of reparative processes, they became embedded within a capillary-rich granulation tissue. Subsequently, fibrosis of the submucosa develops with persistent mucus pools. Our results thus show that removal of biopsy material from adenomas can result in misplacement of tumour particles into the submucosa. These changes were observed in flat or broad-based tumours, and epithelial misplacement appears to be detectable within only a short period after biopsy. For the differential diagnosis, it is important to distinguish these changes from invasive carcinoma.

Simulated operations by pulsatile organ-perfusion in minimally invasive surgery.

The rapid amplification of indications and areas of application of laparoscopic or thoracoscopic techniques leads to increasing problems and needs in surgical training. Pulsatile perfusion of organs (POP) and organ groups in laparoscopic training devices (pelvitrainers) aids in creating optimum conditions for the simulation of difficult intraoperative situations and complications. Simple applicability, low cost, and the possibility of a noticeable reduction of the currently required animal experiments render POP an ideal training method for minimally invasive surgery.