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P M Go

Publications and source records attributed to P M Go.

At least 19 recordsLinked to original sources

[The 'Inguinal Hernia' guideline of the Association of Surgeons of the Netherlands].

The 'Inguinal hernia' guideline was written over a period of two years by nine surgeons (including one epidemiologist) from all regions of the Netherlands with demonstrable clinical and scientific expertise in the area of inguinal surgery after a training course on 'The development of evidence-based guidelines'. A draft of the guideline was on the website of the Association of Surgeons of the Netherlands for a period of three months, during which time the members of the society could comment on its contents interactively. The guideline comprises chapters on risk factors and prevention, diagnostics, indications for treatment, treatment, day surgery, antibiotics, thrombosis prophylaxis, training, anaesthesia, postoperative pain control, complications, costs, aftercare, and specific aspects of inguinal hernia in children. For the treatment of adult patients a mesh technique is recommended. The Lichtenstein technique is recommended as the first choice for uncomplicated primary inguinal hernia. Laparo-endoscopic techniques can be used by trained teams for specific indications. Other techniques have not been compared with the current methods of treatment sufficiently. It is recommended that the operations be carried out in daycare and that the use of local anaesthesia should be considered more often. The diagnosis of inguinal hernia in a child is based on the physical examination. It is recommended that the surgeon should not rely solely on the history but confirm the presence of a hernia personally. The treatment of a paediatric inguinal hernia is always operative. Generally, the younger the child, the more urgent the operation because of the increased risk of incarceration in infants, particularly premature babies. There is no indication for routine exploration of the contralateral groin. If an incarcerated hernia cannot be reduced, emergency operation is necessary and referral to a paediatric surgical centre must be considered. The implementation and effectiveness of the guideline will be measured by taking an inventory of all inguinal hernia operations performed in the Netherlands before and after its publication.

Adult↗

Laparoscopic techniques versus open techniques for inguinal hernia repair.

BACKGROUND: Inguinal hernia repair is the most frequently performed operation in general surgery. The standard method for inguinal hernia repair had changed little over a hundred years until the introduction of synthetic mesh. This mesh can be placed by either using an open approach or by using a minimal access laparoscopic technique. Although many studies have explored the relative merits and potential risks of laparoscopic surgery for the repair of inguinal hernia, most individual trials have been too small to show clear benefits of one type of surgical repair over another. OBJECTIVES: The objective of this review was to compare minimal access laparoscopic mesh techniques with open techniques. Comparisons of open mesh techniques versus open non-mesh techniques have been considered in a separate Cochrane review. SEARCH STRATEGY: We searched MEDLINE, EMBASE, and The Cochrane Central Controlled Trials Registry for relevant randomised controlled trials. The reference list of identified trials, journal supplements, relevant book chapters and conference proceedings were searched for further relevant trials. Through the EU Hernia Trialists Collaboration (EUHTC) communication took place with authors of identified randomised controlled trials to ask for information on any other recent and ongoing trials known to them. Specialists involved in research on the repair of inguinal hernia were contacted to ask for information about any further completed and ongoing trials. The world wide web was also searched. SELECTION CRITERIA: All published and unpublished randomised controlled trials and quasi-randomised controlled trials comparing laparoscopic groin hernia repair with open groin hernia repair were eligible for inclusion. Trials were included irrespective of the language in which they were reported. DATA COLLECTION AND ANALYSIS: Individual patient data were obtained, where possible, from the responsible trialist for all eligible studies. All reanalyses were cross-checked by the reviewers and verified by the trialists before inclusion. Where IPD were unavailable additional aggregate data were sought from trialists and published aggregate data checked and verified by the trialists. IPD were available for 25 trials, additional aggregated data for seven and published data only for nine. Where possible, time to event analysis for hernia recurrence and return to usual activities were performed on an intention to treat principle. The main analyses were based on all trials. Sensitivity analyses based on the data source and trial quality were also performed. Pre-defined subgroup analyses based on recurrent hernias, bilateral hernias and femoral hernias were also carried out. MAIN RESULTS: 41 published reports of eligible trials were included involving 7161 participants. Sample sizes ranged from 38 to 994, with follow-up from 6 weeks to 36 months. Duration of operation was longer in the laparoscopic groups (WMD 14.81 minutes, 95% CI 13.98 to 15.64; p<0001). Operative complications were uncommon for both methods but more frequent in the laparoscopic group for visceral (Overall 8/2315 versus 1/2599) and vascular (Overall 7/2498 versus 5/2758) injuries. Length of hospital stay did not differ between groups (WMD -0.04 days, 95% CI -0.08 to 0.00; p=0.05, but return to usual activity was earlier for laparoscopic groups (HR 0.56, 95%CI 0.51 to 0.61; p<0.0001 - equivalent to 7 days). The data available showed less persisting pain (Overall 290/2101 versus 459/2399; Peto OR 0.54, 95% CI 0.46 to 0.64; p<0.0001), and less persisting numbness (Overall 102/1419 versus 217/1624; Peto OR 0.38, 95% CI 0.4286 to 0.49; p<0.0001) in the laparoscopic groups. In total, 86 recurrences were reported amongst 3138 allocated laparoscopic repair and 109 amongst 3504 allocated to open repair (Peto OR 0.81, 95% CI 0.61 to 1.08; p = 0.16). The use of mesh during laparoscopic hernia repair is associated with a reduction in the risk of hernia recurrence, significantly so for the transabdominal preperitoneal repair (TAPP) versus open non-mesh repair (overall 26/1440 versus preperitoneal repair (TAPP) versus open non-mesh repair (overall 26/1440 versus 47/1119; Peto OR 0.45, 95% CI 0.28 to 0.72; p=0.0009). However, no difference was detected when comparing laparoscopic methods with open mesh methods of hernia repair. REVIEWER'S CONCLUSIONS: The use of mesh during laparoscopic hernia repair is associated with a relative reduction in the risk of hernia recurrence of around 30-50%. However, there is no apparent difference in recurrence between laparoscopic and open mesh methods of hernia repair. The data suggests less persisting pain and numbness following laparoscopic repair. Return to usual activities is faster. However, operation times are longer and there appears to be a higher risk of serious complication rate in respect of visceral (especially bladder) and vascular injuries.

Hernia, Inguinal↗

Open mesh versus non-mesh for repair of femoral and inguinal hernia.

BACKGROUND: Inguinal hernia repair is the most frequent operation in general surgery. Until recently the standard procedure has been open musculo-aponeurotic repair using sutures under tension to close the defect but 'tension-free' repair using prosthetic mesh is becoming increasingly common in many countries. OBJECTIVES: The purpose of this review is to evaluate open mesh techniques in comparison with open non-mesh techniques for the surgical repair of groin hernia. SEARCH STRATEGY: Electronic databases were searched and further trials were sought from the reference lists of reports of known trials. Through the EU Hernia Trialists Collaboration authors of identified randomised controlled trials were asked for information on any other trials known to them. There was no language restriction. SELECTION CRITERIA: Studies were eligible for inclusion if they were randomised or quasi-randomised trials comparing either a) open mesh with open non-mesh repair of groin hernia or b) open flat mesh repair with plug and mesh repair of groin hernia. DATA COLLECTION AND ANALYSIS: For each outcome the results were derived using data from the best available source. The majority of data for this review came from individual patient data (IPD) supplied by the trialists. When these were unavailable data came from additional aggregated information or from published trial reports. All trials were analysed using the 'intention to treat' principle. MAIN RESULTS: Twenty trials comparing open mesh with open non-mesh repair were identified. Open mesh methods, on average, took 7-10 minutes less to perform than Shouldice procedures, but took 1-4 minutes longer than other non-mesh methods. There were no clear differences between mesh and non-mesh groups for haematomas, seromas or wound/superficial infections. Three serious operative complications were reported after open mesh repair and three following non-mesh repair. Overall, those in the mesh groups had a shorter length of hospital stay and quicker return to usual activities, but this pattern was not observed for all trials. There was a suggestion that persisting pain was less frequent after mesh repair than after non-mesh repair but this result was dependent on one trial and data were not available for 11 trials. There was no evidence of a difference between the groups with respect to persisting numbness. Fewer hernia recurrences were reported after mesh repair (Peto OR: 0.37, 95% CI: 0.26 to 0.51). There were too few data to reliably address differential effects for patients with recurrent, bilateral or femoral hernias. Two trials comparing flat mesh with plug and mesh were identified. There was no clear evidence of differences between the groups. REVIEWER'S CONCLUSIONS: There is evidence that the use of open mesh repair is associated with a reduction in the risk of recurrence of between 50% and 75%. Although the trials were heterogeneous there is also some evidence of quicker return to work and of lower rates of persisting pain following mesh repair.

Clinical Trials as Topic↗

[Ambulatory laparoscopic cholecystectomy is as effective as hospitalization and from a social perspective less expensive: a randomized study].

OBJECTIVE: To compare the effects and costs of an ambulatory treatment versus an overnight stay for laparoscopic cholecystectomy. DESIGN: Prospective, randomised. METHOD: In the St Antonius hospital, Nieuwegein, the Netherlands, 86 patients with symptomatic cholelithiasis without comorbidity underwent either ambulatory (AM: 42 patients: 8 men and 36 women; mean age: 48.9 years (SD: 11.9)) or overnight stay (OS: 44 patients: 10 men and 32 women; mean age: 44.9 years (SD: 11.8)) laparoscopic cholecystectomy in the period 1 November 1997-30 September 1999. The following were registered: operative time, complications, hospital stay and readmissions, as well as reported pain, nausea, activity resumption, quality of life and patient satisfaction. The cost analysis was performed from a societal and hospital perspective. RESULTS: In the OS group one laparoscopic procedure was converted to open cholecystectomy, two relaparotomies were performed due to intra-abdominal haemorrhage and 1 patient had a catheter inserted due to urine retention. Two patients were readmitted, one for postoperative pancreatitis and the other for a retained bile duct stone. In the AM group one laparoscopic procedure was converted to open cholecystectomy, in 1 patient a wound abscess was treated with drainage in the outpatient clinic, in 1 patient there was peroperative stone loss without further complications and in 1 patient a catheter was placed to drain peroperative bile and blood loss. In the AM group 11 (26%) patients were kept overnight due to nausea and/or pain (n = 7) or one of the aforementioned complications (n = 4). Two patients were readmitted within 24 hours of being discharged due to abdominal pain. The average hospital stay was 3.1 (OS) versus 1.7 (AM) days. The quality of life, pain, nausea and activity resumption were comparable for both groups. Due to the difference in hospital stay, costs for the ambulatory procedure were lower. CONCLUSION: Laparoscopic cholecystectomy was successfully performed as an ambulatory surgery procedure in 69% of the patients. The quality of life, patient satisfaction and resumption of activities in both groups were comparable. The ambulatory treatment was less expensive.

Adult↗

Timing of adoption of laparoscopic cholecystectomy in Denmark and in The Netherlands: a comparative study.

Laparoscopic cholecystectomy (LC) has diffused rapidly in most industrialised countries. The aim of this study has been to analyse the impact of different hospital characteristics on the hospital adoption of LC in Denmark and The Netherlands. Data on the timing of the adoption of LC and hospital characteristics (hospital size, teaching status and location) were retrieved in both countries. Proportional hazard regression was used to analyse different multivariate models. A total of 59 Danish and 109 Dutch hospitals adopting LC were identified. The multivariate analyses showed that increased hospital size was associated with relatively early adoption of LC in Denmark. Neither this nor other hospital characteristics influenced the timing of adoption in The Netherlands. As in other countries studied, hospital size is identified as an important factor in hospital adoption, whereas teaching status and location play a more limited role. The study shows that a multivariate method, such as the proportional hazard regression, can be used to elucidate differences among countries of the impact of different factors on the adoption of medium-ticket technologies like LC. Such multinational comparisons provide valuable information for health policy and planning.

Cholecystectomy, Laparoscopic↗

[Assessment of day surgery in a district training hospital: safety, efficacy and patient's satisfaction].

OBJECTIVE: To assess the quality of day surgery in the St. Antonius Hospital in Nieuwegein, the Netherlands. DESIGN: Prospective and descriptive. METHODS: During one year all patients treated by general surgeons in ambulatory surgery of the St. Antonius Hospital, Nieuwegein, the Netherlands (breast surgery (n = 232), hernia repair (n = 143), varicose vein surgery (n = 137), lymph node or lump excision (n = 85), (peri-)anal surgery (n = 70), ganglion surgery (n = 41), removal of bone implants (n = 41), laparoscopic cholecystectomy (n = 23), miscellaneous (n = 82); total 854) were evaluated by telephone questionnaires six weeks after surgery, to measure the following three aspects of quality of care: safety, efficacy and patient's satisfaction. Questions were asked about complications, visits to the emergency room, the outpatient clinic and the general practitioner and extra care at home. Unplanned clinical admissions following day surgery and re-admissions were registered. All outpatient clinic charts were also checked for complications. Whenever the registration of complications was incomplete the patient's general practitioner was contacted. All patients gave informed consent. RESULTS: After 854 planned day cases 823 patients (96.4%) returned home the same day. Reasons for clinical admission following day surgery were pain and/or nausea (n = 8), an operation late in the afternoon (n = 7), haemorrhage (n = 6), more extensive surgery than expected (n = 3), others (n = 7). Of all patients who returned home the same day and about whom the interview yielded adequate information (n = 656; 80%) 54 (7%) suffered from a complication (wound infection (n = 28), haemorrhage (n = 7), haematoma (n = 5), seroma (n = 3), phlebitis (n = 2), infection skin (n = 2), wound dehiscence (n = 2), others (n = 5)). Six patients were re-admitted. In the hospital and outpatient clinic 40 patients were seen without an appointment (6%) and 91 patients visited their general practitioner (14%). After surgery 84 (13%) patients were helped at home by friends or family. Of the group of patients who were successfully treated in day care 14% would have preferred an overnight stay.

Adult↗

Laparoscopic or conventional Nissen fundoplication for gastro-oesophageal reflux disease: randomised clinical trial. The Netherlands Antireflux Surgery Study Group.

BACKGROUND: For the surgical treatment of gastrooesophageal reflux disease (GORD), laparoscopic Nissen fundoplication has largely replaced the open procedure. Retrospective and prospective non-randomised studies have shown similar results after laparoscopic Nissen fundoplication compared with the open procedure. METHODS: In a multicentre randomised trial candidates for surgical treatment of GORD were randomly assigned to either laparoscopic or open 360 degrees Nissen fundoplication. Primary endpoints were dysphagia, recurrent GORD, and intrathoracic hernia. Secondary endpoints were effectiveness and quality of life. This planned interim analysis focuses on endpoints and complications and in-hospital costs. FINDINGS: At the time of interim analysis, 11 patients in the laparoscopic group and one in the conventional group had reached a primary endpoint (p=0.01; relative risk=8.8, 95% CI 1.2-66.3). This difference was caused mainly by whether or not patients had dysphagia (seven patients in the laparoscopic group and none in the conventional group, p=0.016). INTERPRETATION: Although laparoscopic Nissen fundoplication was as effective as the open procedure in controlling reflux, the significantly higher risk of reaching a primary endpoint in the laparoscopic group led us to stop the study.

Adult↗

[Laparoscopic inguinal hernia operation].

After the introduction of laparoscopic operations for repair of inguinal hernias, circa 1990, randomized comparative studies showed that this method causes less postoperative pain and requires a shorter recovery period than conventional operations. The duration of follow-up is still too short for comparison of proportions of recurrences. The costs of laparoscopic interventions are higher for the hospital (among other things because of the use of disposable instruments) and lower for society (because of shorter absenteeism). Implementation of the intervention by allotment of a higher fee to hospitals has not been done, because meanwhile a third method--conventional surgery with implantation of a prosthetic mesh in ambulatory surgery--has become possible. A meta-analysis based on European registration of all treated patients will once more have to demonstrate what method of treatment is to be preferred.

European Union↗

Radiological anatomy of the groin region.

The purpose of this paper is to give an overview of the anatomy of the inguinal region, and to discuss the value of various imaging modalities in the diagnosis of groin hernias. After description of the gross anatomy of the groin, attention is focused on the anatomic features of conventional herniography, US, CT, and MRI. Advantages, disadvantages, and accuracy of each technique is discussed briefly.

Hernia, Inguinal↗

High recurrence rate 12 years after primary inguinal hernia repair.

OBJECTIVE: To find out the long term recurrence rate after repair of the inguinal ligament (Griffith) for inguinal hernia in one hospital. DESIGN: Retrospective study. SETTINGS: Teaching hospital, The Netherlands. SUBJECTS AND INTERVENTION: All patients who had had a Griffith repair for a primary inguinal hernia in 1985 were re-examined after at least 12 years by an independent examiner. RESULTS: Of the 102 patients included in the study, 45 patients had died and 17 could not be traced. Of the remaining 40 patients (45 hernias), 10 (22%) had developed recurrences. In 4 patients the asymptomatic hernia was discovered by the investigator. 11 further patients had developed a hernia on the opposite site resulting in a total of 16 patients (40%) with bilateral hernias. CONCLUSIONS: The long term recurrence rate of an inguinal hernia by reconstruction of the inguinal ligament is high and even higher when assessed by physical examination. The high recurrence rate and frequent bilateral recurrence might favour repairs with mesh reinforcement.

Adult↗

Preoperative and postoperative assessment of laparoscopic inguinal hernia repair by dynamic MRI.

RATIONALE AND OBJECTIVES: To determine the value of dynamic MRI for seroma detection, hernia recurrence, and mesh placement in patients after laparoscopic inguinal hernia repair. METHODS: Thirteen inguinal hernias in 10 consecutive patients were evaluated before and after surgery by using an MRI protocol consisting of coronal T1-weighted (fast field echo) and T2-weighted (turbo spin-echo) images and two sequences obtained during straining (turbo field echo gradient technique). All patients underwent a transabdominal preperitoneal laparoscopic inguinal hernia repair. MRI scans were reviewed for the presence of postoperative fluid collections, recurrent hernia, and mesh localization. RESULTS: In all patients, an inguinal hernia was identified on the preoperative MRI and was absent on the postoperative MRI. In all patients treated laparoscopically, the mesh and its position were clearly identified. Three small fluid collections were found on the postoperative MRI scans. CONCLUSIONS: Dynamic MRI can demonstrate small, postoperative fluid collections and a sufficient hernioplasty by showing the proper position of the mesh and the absence of a hernia.

Female↗

Open or laparoscopic preperitoneal mesh repair for recurrent inguinal hernia? A randomized controlled trial.

BACKGROUND: Giant prosthetic reinforcement of the visceral sac (GPRVS), an open preperitoneal mesh repair, is a very effective groin hernia repair. Laparoscopic transabdominal preperitoneal repair (TAPP), based on the same principle, is expected to combine low recurrence rates with minimal postoperation morbidity. METHODS: Seventy-nine patients with 93 recurrent and 15 concomitant primary inguinal hernias were randomized between GPRVS (37 patients) and TAPP (42 patients). Operating time, complications, pain, analgesia use, disability period, and recurrences were recorded. RESULTS: Mean operating time was 56 min with GPRVS versus 79 min with TAPP (p < 0. 001). Most complications were minor, except for a pulmonary embolus and an ileus, both after GPRVS. Patients experienced less pain after a laparoscopic repair. Average disability period was 23 days with GPRVS versus 13 days with TAPP (p = 0.03) for work, and 29 versus 21 days, respectively (p = 0.07) for physical activities. Recurrence rates at a mean follow-up of 34 months were 1 in 52 (1.9%) for GPRVS versus 7 in 56 (12.5%) for TAPP (p = 0.04). Hospital costs in U.S. dollars were comparable, with GPRVS at $1,150 and TAPP at $1,179. CONCLUSIONS: Laparoscopic repair of recurrent inguinal hernia has a lower morbidity than GPRVS. However, laparoscopic repair is a difficult operation, and the potential technical failure rate is higher. With regard to recurrence rates, the open preperitoneal prosthetic mesh repair remains the best repair.

Adult↗

Lipid solubilization in human gallbladder versus hepatic biles.

BACKGROUND/AIMS: Cholesterol crystallizes more rapidly in gallbladder than in hepatic biles, supposedly due to formation of cholesterol-supersaturated vesicles in concentrated gallbladder biles because of preferential micellization of phospholipids compared to cholesterol. We therefore aimed to compare lipid solubilization in hepatic and gallbladder biles. METHODS: Mixed micellar and vesicular phases were separated from hepatic and associated gallbladder biles of seven cholesterol gallstone patients by using state-of-the-art gel filtration with bile salts at intermixed micellar/intervesicular compositions and concentrations in the eluant. RESULTS: Vesicles were found in 6 out of 7 hepatic biles, but only in 2 of the corresponding gallbladder biles. Both percentage (7.8+/-5.1 vs. 36.3+/-7.6%; p = 0.01) and amount (0.9+/-0.2 vs. 1.7+/-0.3 mM; p = 0.06) of vesicular cholesterol were lower in gallbladder biles. Similar results were found for vesicular phospholipids (1.3+/-0.8 vs. 11.6+/-6.0%; p = 0.05; and 0.3+/-0.1 vs. 1.1+/-0.5 mM; p = 0.07). The vesicular cholesterol/ phospholipid ratio was 1.7+/-0.5 in hepatic bile but 4.3 and 1.8 in the 2 gallbladder biles which contained vesicles. Mixed micelles in gallbladder biles had a higher cholesterol saturation index than mixed micelles in hepatic biles (1.43+/-0.11 vs. 1.15+/-0.07; p = 0.02). CONCLUSIONS: Concentration of bile in the gallbladder leads to decreased vesicular lipid contents. The finding of supersaturated mixed micelles in the absence of vesicles in a significant number of patients points to the possibility of non-vesicular modes of crystallization.

Bile Ducts↗

Detection of groin hernia with physical examination, ultrasound, and MRI compared with laparoscopic findings.

OBJECTIVE: To determine the diagnostic accuracy of physical examination, ultrasound, and dynamic MRI in patients with inguinal hernia. METHODS: In 41 patients with clinically evident herniations, 82 groins were evaluated using a standard ultrasound and MRI protocol, the latter including T1- and T2-weighted sequences as well as two dynamic sequences. All ultrasound examinations and MRI scans were reviewed without knowledge of clinical findings. In all cases, correlation with findings at laparoscopic surgery was made. RESULTS: At surgery, 55 inguinal herniations were found. Physical examination revealed 42 herniations (one false-positive finding), whereas ultrasound made the diagnosis of a hernia in 56 cases (five false-positive and four false-negative findings). MRI diagnosed 53 herniations (one false-positive and three false-negative findings). Thus, sensitivity and specificity figures were 74.5% and 96.3% for physical examination, 92.7% and 81.5% for ultrasound, and 94.5% and 96.3% for MRI. CONCLUSIONS: In patients with clinically uncertain herniations, MRI is a valid diagnostic tool with a high positive predictive value.

Adult↗

[Increase of surgical day treatment in the Netherlands].

OBJECTIVE: To assess the quantitative development of day surgery in the Netherlands. DESIGN: Descriptive. SETTING: St. Antonius Hospital, Nieuwegein, the Netherlands. METHOD: Numbers of admissions in the period 1984-1995 were obtained from Dutch data bases of the National Hospital Institution (NZi). From SIG Health Care Information numbers were obtained with regard to seven specified interventions in the years 1991 to 1995, i.e. breast tumour excision, inguinal hernia repair, varicose vein operation, laparoscopic sterilisation, knee arthroscopy, cataract operation and tonsillectomy. The increase if any of the number of interventions in day care was determined by placing the hospitals in the order of decreasing proportions of day care, and subsequently applying the proportions of the 5th and 10th hospitals, respectively, to the whole group. RESULTS: The number of day care admissions rose from 172,000 (9.9% of all admissions) to 649,000 (29.1%). Of all interventions studied, the percentage carried out in day care increased; the percentages varied greatly from one hospital to another. In 1995, the mean number of interventions in daytime was 115,000 (57% of all 201,000 interventions). The shift from interventions during hospitalization to day care would be 42,000 and 51,000 (21% and 25% respectively, of 201,000), respectively; operations performed in day care would then amount to 166,000 (83% of the total number of interventions) and 157,000 (78%). CONCLUSION: Of the interventions studied, the proportion carried out in day care increased to 57%. In view of the intra- and interhospital differences, a considerable increase of day care in the near future is possible.

Adolescent↗

[Digital imaging and robotics in endoscopic surgery].

The introduction of endoscopical surgery has among other things influenced technical developments in surgery. Owing to digitalisation, major progress will be made in imaging and in the sophisticated technology sometimes called robotics. Digital storage makes the results of imaging diagnostics (e.g. the results of radiological examination) suitable for transmission via video conference systems for telediagnostic purposes. The availability of digital video technique renders possible the processing, storage and retrieval of moving images as well. During endoscopical operations use may be made of a robot arm which replaces the camera man. The arm does not grow tired and provides a stable image. The surgeon himself can operate or address the arm and it can remember fixed image positions to which it can return if ordered to do so. The next step is to carry out surgical manipulations via a robot arm. This may make operations more patient-friendly. A robot arm can also have remote control: telerobotics. At the Internet site of this journal a number of supplements to this article can be found, for instance three-dimensional (3D) illustrations (which is the purpose of the 3D spectacles enclosed with this issue) and a quiz (http:@appendix.niwi. knaw.nl).

Computer Communication Networks↗