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At least 1,135 records · Page 63Linked to original sources

PubMed2006

[Video-assisted cardiac valve surgery].

BACKGROUND AND PURPOSE: Advances in the development of video-assisted systems for minimally invasive surgery now allow to perform cardiac surgery via a smaller anterolateral thoracotomy in order to reduce trauma, pain and improve cosmetics. In addition, due to sternal sparing, pulmonary function should improve resulting in reduced hospital stay and costs. However, only few centers worldwide abstain from spreading the ribs thus accepting considerable pain and reduced patient comfort. The minimally invasive approach described here uses a right-sided anterolateral incision (4-5 cm), a soft-tissue retractor and femorofemoral perfusion with endoclamping under continuous TEE (transesophageal echocardiography) control. It was the aim of this retrospective analysis to determine feasibility, safety and effectiveness of the method. PATIENTS AND METHODS: At the West German Heart Center Essen, 47 patients were operated using minimally invasive endoscopic techniques between January 2004 and April 2006 on the mitral valve (n = 31), mitral and tricuspid valve (n = 9), including mini-Maze procedure in two cases, as well as atrial septal defects (n = 5) and myxomas (n = 2). Mean age was 58 +/- 15.2 years (range 29-87 years), NYHA II-III, 20 patients were male. RESULTS: All but one patient survived (2.1%). Conversion to median sternotomy was necessary in three of the first twelve patients. After a mean follow-up period of 18 months all reconstructions and valves were competent, freedom from cardiac reoperation was 100%. On a visual analog scale 91% ot the patients reported no or mild postoperative pain, 96% felt they had an aesthetically pleasing scar. All but one patients would choose the same operation again. CONCLUSION: Videoscopically assisted, endoscopic cardiac surgery can be performed safely, but requires a learning curve and intense training. After evaluation of efficacy and safety it is now the authors' exclusive approach to isolated atrioventricular valve disease with an ideal pain-free and cosmetic result.

Adult↗

PubMed2006

A special instrument: the LISS tractor.

OBJECTIVE: Facilitation of reduction and retention in LISS (Less Invasive Stabilizing System) plate osteosynthesis of fractures of the distal femur by application of the large AO distractor. INDICATIONS: Any distal femoral fracture suited to LISS plate osteosynthesis. CONTRAINDICATIONS: Distraction can lead to a pullout of the Schanz screws in patients with pronounced osteoporosis. SURGICAL TECHNIQUE: Supine. Normal LISS osteosynthesis with lateral or parapatellar approaches. Insertion of one Schanz screw proximal to the end of the plate through a stab incision. Introduction of the LISS plate in the usual fashion and insertion of a second Schanz screw into plate hole "A", parallel to the joint. Assembly of the distractor onto the Schanz screws, distraction of the femur to the correct length and correction of varus/valgus alignment with the aid of the cable method, as well as correction of ante- and retrocurvature by insertion of an additional Schanz screw at the anterior aspect. At least two locking head screws should be inserted into the plate holes both proximally and distally. Removal of the AO distractor. Assembly of aiming guide and insertion of further screws into additional plate holes using the guide sleeve. RESULTS: Between May 1998 and September 2001, a total of 42 patients had their distal femoral fractures stabilized by LISS. The AO distractor was used from the 18th case onward. A time saving of approximately 13% was estimated, taking the learning curve of the LISS system into consideration. Three of 42 fractures showed relevant postoperative varus or valgus malalignment. No rotational malalignment was found. An effect of the LISS tractor on the incidence of malalignment could not be found with the limited number of cases examined; however, malalignment was correlated well with the rates found in literature for distal femoral fractures.

Bone Plates↗

PubMed2006

Minimally invasive total hip replacement with the patient in the supine position and the contralateral leg elevated.

OBJECTIVE: Supine positioning of the patient taking into account - the demands of anesthesia in an emergency requiring intubation, - minimal time for sterile draping, - patient position can be adjusted by the assistants, - easier implant positioning due to the supine position. Reduction of operative trauma with earlier mobilization and shorter rehabilitation time compared with conventional technique. Application of standard instruments and implants. INDICATIONS: Coxarthroses, necroses of the femoral head. CONTRAINDICATIONS: For the "gynecologic position": - hip joint arthrodesis of the contralateral side. - flexion of the contralateral side < 20 degrees . For minimally invasive total hip replacement: - severe anatomic deformities. - revision operations. POSITIONING AND SURGICAL TECHNIQUE: Supine position of the patient with the contralateral leg held at approximately 30 degrees flexion in a gynecologic footrest attached to the operating table. Leg support that can be lowered for the leg being operated on. Minimally invasive anterolateral approach without dissection of muscles or tendons. Resection of the femoral neck and removal of the femoral head. Preparation of the acetabulum and implantation of the cup. Hyperextension of the leg by lowering the leg support with subsequent adduction and external rotation beneath the elevated contralateral leg. Preparation of the femur and implantation of the stem with subsequent repositioning and wound closure. RESULTS: 185 total hip replacements were performed with this positioning and surgical technique from September 2004 to June 2005. The first 108 minimally invasive procedures were compared with 117 conventional procedures. The patients operated in minimally invasive technique generally did better in terms of operating time, blood loss, use of analgesics, rehabilitation time, and functional outcomes. In seven patients, shaft fissures occurred within the first 3 months due to too abrupt intraoperative dislocation of the leg (learning curve!), but were all treated by application of cerclage and healed uneventfully.

Adult↗

PubMed2002

[Antireflux surgery in Germany. Results of a representative survey with analysis of 2,540 antireflux operations].

INTRODUCTION: Aim of this study was the evaluation of antireflux surgery in Germany. METHODS: An anonymous questionnaire including 288 structured items about diagnostic and therapeutic approaches, complications and mortality was sent to 33% randomly selected German general surgeons (n = 546) at the end of 2000. RESULTS: A total of 2,540 antireflux procedures was reported, 81% were performed laparoscopically; 65% were total, 31% partial fundoplications. The number of surgeons offering laparoscopic antireflux surgery increased from 0.3% in 1990 to 5% in 1995 and to 32% in 2000. Numerous modifications regarding esophageal mobilisation, crural repair, kind and extension of the wrap, use and size of a bougie, as well as an additional gastropexy were observed. Morbidity rates were significantly higher for open than for laparoscopic procedures (15.0% vs. 7.7%), mainly caused by wound healing problems (4.4% vs. 0.8%) and splenic lesions (3.1 vs. 0.6%). Gastric and esophageal perforations were similar in both groups (1.1 vs. 0.9%). Hospital mortality rate was 0.1%. We observed a frequency dependent learning curve regarding complication rates after laparoscopic antireflux surgery (< 11 fundoplication p.a.: 14.0%; 11-30 fundoplications: 7.3% (p = 0.05); > 30 fundoplications: 4.2% (p = 0.05%). Long-term-dysphagia occurred more often after 360 degrees-versus partial fundoplications (6.6% vs. 2.4%; p < 0.001) and after Nissen/Nissen-Rossetti--than after Floppy-Nissen-procedures (6.6% vs. 3.6%, p = 0.1). The recurrency rate was 9.3% without significant differences between the procedures. CONCLUSION: Laparoscopy has replaced the open technique. Different technical approaches significantly affect the outcome after laparoscopic antireflux surgery in Germany.

Cause of Death↗

PubMed2003

[Laparoscopic cholecystectomy. Training on a bio-simulation model with learning success documented using score-cards].

The possibilities of gaining theoretical knowledge in surgery are virtually unlimited. To acquire practical skills,however, the availability and willingness of the patient are the limiting factors. With the development of training tools and structured courses, experience can be gained independently of the clinical situation. To objectify and record individual performance and improvement, and to define further potential, a scoring system is necessary. Using the example of laparoscopic cholecystectomy, a training program was combined with an evaluation system and the beginners' learning curves were recorded during the course of a training week. The present study shows that first experiences and measurable improvements can be reliably assessed within one week's structured training on a simulation model.

Animals↗

PubMed2004

[The choice between transperitoneal and retroperitoneal adrenalectomy. A prospective study].

INTRODUCTION: The aim of this prospective study was to evaluate the optimal surgical approach to endoscopic adrenalectomy. PATIENTS AND METHODS: Between March 1997 and February 2003, we performed 221 endoscopic adrenalectomies in 202 patients (right side 83, left side 100, bilateral 19), with an conversion rate of 2,5%. In 197 patients endoscopic adrenalectomy was carried out via retropertioneal approach 128 times and via transperitoneal approach 88 times. RESULTS: Endoscopic adrenalectomy was performed in 98% of the total number patients. No statistically significant influence ( P=0.05) was found for the parameters intraoperative blood loss, rate of postoperative complications, or duration of hospitalization in regard to the procedure. The operative time and learning curve were significantly longer with the retroperitoneal approach. Multivariate analysis identified surgical approach, tumor size (5 cm), and body mass index (25) as independent factors for operative time. CONCLUSION: The lateral transperitoneal approach is the optimal procedure for endoscopic adrenalectomy.

Adrenal Gland Neoplasms↗

PubMed1996

[Endoscopic hernia surgery (TAPP)--gold standard in management of recurrent hernias?].

From April 1993 to December 1995 210 TAPP procedures were performed because of recurrent hernia. With the TAPP method there is no difference between primary and recurrent repair. All procedures in this study were done with general anaesthesia by senior surgeons. The learning curve shows a reduction of operation time (60 to 55 min) with increasing experience and a reduction in complications as well (total 4.3%). Recurrence was observed in two cases. The reasons for these recurrences were technical failures during the previous repair. In both cases a second TAPP repair was carried out successfully. The main advantage of TAPP in recurrent hernia is that this method gives possibilities to avoid anterior scar tissue. Secondly tension-free repair can be combined with the benefit of the minimal access technique. For this reason, the TAPP procedure must be considered the method of choice in recurrent hernia repair.

Adult↗

PubMed1997

[Appendectomy 1997--open or closed?].

Unlike laparoscopic cholecystectomy, laparoscopic appendectomy (LAE) has not yet become popular. Are there no significant advantages? Or is the poor acceptance of LAE related to its longer learning curve, longer operative times and the need for additional equipment, which lead to some inconvenience when the procedure is done on an emergency basis? LAE may be performed as safely as open appendectomy (OAE) with fewer wound complications. Superior laparoscopic exploration allows an accurate diagnosis and reduces the rate of negative appendectomies. In contrast, postoperative pain, recovery and the cosmetic result are equal to or at best slightly better than in open surgery. Therefore, in the routine patients, there is no need to replace OAE by LAE. In the case of an uncertain diagnosis, the laparoscopic approach is generally superior, allowing thorough abdominal exploration. This has to be considered in each individual case; however, women with lower abdominal pain and suspected appendicitis will certainly benefit from laparoscopy, as well as older patients with an unclear diagnosis. The lower rate of wound infections is beneficial to obese patients and to patients with gangrenous or perforated appendicitis. Furthermore, the decision for one procedure or the other is influenced by the patient's individual preference and cosmetic aspects. The verifiable benefit of the laparoscopic procedure for certain categories of patients and the potential advantages in the individual case suggest that competent handling of laparoscopic technology will be required in future. Therefore, experienced surgeons should take more active interest in instruction and training--even when surgery has to be performed after hours.

Appendectomy↗

PubMed1997

[Laparoscopic cholecystectomy in therapy of acute cholecystitis: immediate versus interval operation].

From January 1991 to May 1996 a total of 3,010 cholecystectomies was performed for cholelithiasis. Pathohistologically an acute cholecystitis was found in 483 patients (16%). The overall proportion of laparoscopic operations has increased from 12.5% in 1991 to 96.6% at present. In patients with acute cholecystitis the proportion of laparoscopic operations has increased from initially only 1.87% up to 83.3%. The duration of surgery (81 min versus 54 min), rate of conversion (12% versus 1.07%) and rate of complications (7.76% versus 2.2%) were all significantly higher in cases of acute cholecystitis than in those without inflammation. There was no mortality in either group. Furthermore no significant difference was found between patients with histopathologically proven acute inflammation and patients with an acute episode of chronic cholecystitis. The duration of complaints, however, had a significant influence on surgical results. In patients that were either operated on within 48 h after the onset of disease or more than 10 days later, the length of the operation was shorter and the rates of conversion and complications were lower. Our results prove that laparoscopic cholecystectomy is also very successful in cases of acute cholecystitis, though a long learning curve has to be expected. Taking efficiency and economy into consideration, surgery within a few days of the onset of disease must be recommended.

Acute Disease↗

PubMed1998

[Retroperitoneoscopy--experiences with the first cases].

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.

Adolescent↗

PubMed1998

[Sentinel node detection in breast carcinoma].

The aim of sentinel node biopsy (SN) in breast cancer patients is to detect the tumor-draining lymph node by means of isosulfan blue or 99mTc-labelled colloids. SN can be detected in 80 to 85% of the patients, depending on the size of the tumor. Preoperative lymphoscintigraphy permits the draining nodes along the internal mammary artery also to be visualized. The predictive value of the histological findings of SN for lymph nodes obtained from axillary dissection is about 95%. Because of different diagnostic procedures using various radiotracers each center has to follow its own learning curve. To be sure that the nodal status derived from a SN procedure is of identical value to axillary dissection about 100 patients have to undergo sentinel node detection, followed by axillary dissection, and concordant results should be obtained in 95% of them at least. The SN, however, offers a chance of assessing the lymph node at risk for metastasis by more detailed histological procedures. Morbidity as a result of treatment for primary breast cancer can be decreased if only patients suffering from metastatic disease are subjected to axillary dissection. Currently, the indication criteria for a SN procedure should be restricted to small tumors (T1) with clinically uninvolved axillary status and patients with ductal carcinoma in situ (DCIS).

Axilla↗

PubMed1999

[Anal sphincter restoration using dynamic graciloplasty--results of 50 patients].

During the period from 1992 to 1998, 50 patients underwent anal sphincter restoration by dynamic graciloplasty for primary (n = 26) or secondary (n = 6) total anorectal reconstruction (TAR) following abdominoperineal rectal resection (APR) or acquired (n = 9) or congenital (n = 9) fecal incontinence, respectively. Forty-seven patients were operated on by a single-stage procedure using a modified technique for the muscle wrap ("split sling"). Muscle fiber transformation by controlled stimulation was achieved at the beginning of the learning curve within 8 weeks and in the meantime within 4 weeks. Rectal injury (n = 10) turned out to be the most serious postoperative complication and was observed mainly in patients following TAR (n = 8). As the most prominent functional problem constipation in patients following TAR hampered the postoperative functional result; however, this was overcome by regular enemas. An improvement in the continence status was observed in 80% of the patients treated for fecal incontinence, and following APR 66% of the patients had acceptable results without a permanent colostomy.

Adolescent↗

PubMed2000

[A new technique for laparoscopic placement of the adjustable gastric band (LAP-band) for preventing slippage].

BACKGROUND: Slippage (SP) of the stomach is the most common postoperative complication after laparoscopic adjustable silicone gastric banding (LAS-GB) for morbid obesity. METHODS AND PATIENTS: A randomized prospective study was constructed in order to determine whether laparoscopic placement behind the cardia (RKP) is associated with a lower incidence of postoperative SP and pouch dilation than after a retrogastric placement (RGP) of the LAP band using a common technique. Morbidly obese patients presenting for LASGB were randomized to undergo either an RKP (n = 50) or an RGP (n = 51). RESULTS: There were three postoperative SP and three pouch dilations in the RGP group versus no postoperative complication in the RKP group. CONCLUSIONS: The placement of LAP band by the RKP technique is safe and followed by a lower frequency of postoperative complications than with the RGP technique. Clear anatomical landmarks are a benefit to the education and learning curve of LASGB.

Adolescent↗

PubMed2001

[Reduction of surgical access trauma: reliable advantages].

Minimizing the trauma of surgical access is becoming an essential task in modern surgery. The treatment has to become more comfortable for the patient and financial resources have to be considered. Minimally invasive surgery is one of the attempts to achieve this goal. A comparison of surgical procedures, such as cholecystectomy, fundoplication and sigmoid resection in diverticulitis, which are already routinely performed laparoscopically, should be suitable for evaluating whether minor access surgery is really advantageous. The value of minor access may be quantified by different parameters such as influence upon the immunologic function, lung function, postoperative pain, time of hospitalization, return to work and duration of convalescence, as well as a comparison of the effects upon the quality of life index. The data concerning the effects upon immunology are not unequivocal. All in all, the degree of postoperative inflammation seems to be lower after laparoscopic surgery. There is no doubt that there is far less impairment on lung function, the results are better as far as postoperative pain is concerned, and hospitalization and duration of convalescence are shorter. It is also evident that immediately after the operation the quality of life index is superior, which, however, levels out in the course of time. The advantage of minimally invasive surgery is really apparent only after the mastering of the so-called "learning curve" and in cases of benign malignancies. The role of the minor access approach in oncological surgery is, however, not yet defined.

Humans↗

PubMed2005

[Mechatronic in functional endoscopic sinus surgery. First experiences with the daVinci Telemanipulatory System].

BACKGROUND: This study examines the advantages and disadvantages of a commercial telemanipulator system (daVinci, Intuitive Surgical, USA) with computer-guided instruments in functional endoscopic sinus surgery (FESS). METHODS: We performed five different surgical FESS steps on 14 anatomical preparation and compared them with conventional FESS. A total of 140 procedures were examined taking into account the following parameters: degrees of freedom (DOF), duration , learning curve, force feedback, human-machine-interface. RESULTS: Telemanipulatory instruments have more DOF available then conventional instrumentation in FESS. The average time consumed by configuration of the telemanipulator is around 9+/-2 min. Missing force feedback is evaluated mainly as a disadvantage of the telemanipulator. Scaling was evaluated as helpful. The ergonomic concept seems to be better than the conventional solution. DISCUSSION: Computer guided instruments showed better results for the available DOF of the instruments. The human-machine-interface is more adaptable and variable then in conventional instrumentation. Motion scaling and indexing are characteristics of the telemanipulator concept which are helpful for FESS in our study.

Clinical Competence↗

PubMed2003

[CT-free image guided acetabulum navigation in clinical routine].

After experimental and preclinical evaluation (HAP Paul Award 2001) of the CT-free image-guided surgical navigation system for acetabular cup placement (SurgiGATE C-arm cup" by Medivision, Switzerland), the system was introduced into clinical routine. The computation of the angular orientation of the cup is based on reference coordinates from the anterior pelvic plane concept. A hybrid strategy for pelvic landmark acquisition has been introduced involving percutaneous pointer-based digitization with the noninvasive biplanar landmark reconstruction using multiple registered fluoroscopy images. From January 2001 to December 2002, a total of 256 consecutive patients with primary osteoarthrosis (mean age 69 years, 161 male, 95 female, 132 left, and 124 right hip joints) were operated on with the hybrid CT-free navigation system. During each operation the angular orientation of the inserted implant was recorded. To determine the placement accuracy of the acetabular components, 50 consecutive patients underwent a CT scan 7-10 days postoperatively to analyze the cup position related to the anterior pelvic plane. This was all done blinded by the same investigator with the planning software of the CT-based navigation system of Medivision. There was no significant learning curve observed for the use of the system. The mean value for postoperative inclination was 43 degrees (SD 3.0, range: 37 degrees -49 degrees ) and for anteversion 19 degrees (SD 3.9, range: 10 degrees -28 degrees ). The resulting system accuracy, i.e., the difference between intraoperatively calculated cup orientation and postoperatively measured implant position showed a mean error of 1.5 degrees for the inclination (maximum 5 degrees, SD 1.1) and 2.4 degrees for the anteversion (maximum 6 degrees, SD 1.3). An accuracy of better than 5 degrees inclination and 6 degrees anteversion was achieved under clinical conditions, which implies that there is no significant difference in performance from the established CT-based navigation methods. Image-guided CT-free cup navigation provides a reliable solution for future THA.

Acetabulum↗

PubMed2001

[Precision analysis of navigation-assisted implanted thoracic and lumbar pedicled screws. A prospective clinical study].

A prospective clinical trial was performed to study the accuracy of pedicle screw placement of consecutive computer-aided and conventional techniques. Concerning the clinical performance of the navigation system, the average time of matching has been 8.4 minutes per vertebrae. For evaluation of the results, only complete intraosseous placement of the pedicle screw has been defined as correct position. Any medial or lateral perforation of the cortical structure of the pedicle was recorded as malplacement. In the CT-controlled patients complete intrapedicular placement of the screw was obtained in 36 of 45 thoracic (80%) and in 22 of 27 navigated lumbar (81%) pedicles. In the conventional cohort group 27 of 34 (79%) thoracal and 43 of 52 (83%) lumbar screws were completely in. No radicular neurologic damage, caused by a malplaced transpedicular screw has been observed in both groups. In the presented study is shown, that the application of the computer-assisted freehand navigation can improve results concerning the precision of spinal screw placement. Although, the spinal navigator has to consider a learning curve for the clinical inauguration of the system and the qualification of the implant system for computer-assisted application.

Bone Plates↗

PubMed2001

[LISS tractor. Combination of the "less invasive stabilization system" (LISS) with the AO distractor for distal femur and proximal tibial fractures].

Minimally invasive plate osteosynthesis (MIPO) in conjunction with the less invasive stabilization system (LISS) first requires reduction and retention of the fracture using such aids as external fixation, distractors, and percutaneous reduction clamps before the plate can be applied. Based on the open indirect "biological" technique of osteosynthesis, the LISS was combined with an AO distractor (LISS tractor) integrated into the LISS plate. This made reduction possible against the plate before final fixation of the LISS plate. The LISS tractor concept was validated in three patients and we present the technique here. No malalignments > 5 degrees occurred. Fluoroscopy lasted 3.0 min (range: 2.1-4.5) and the operation 125 min (range: 90-150). Modification of the well-known LISS technique by integrating the distractor into the LISS plate to simplify reduction and to provide temporary retention of the fracture has the potential to reduce the fluoroscopy time, the operation time, the rate of malalignments, and the learning curve for this MIPO technique.

Aged↗