Biomedical subjects

B R Davidson

Publications and source records attributed to B R Davidson.

At least 19 recordsLinked to original sources

PubMed2007

Preoperative chemotherapy and the outcome of liver resection for colorectal metastases.

BACKGROUND: Neoadjuvant systemic chemotherapy is being increasingly used prior to liver resection for colorectal metastases. Oxaliplatin has been implicated in causing structural changes to the liver parenchyma, and such changes may increase the morbidity and mortality of surgery. PATIENTS AND METHODS: A retrospective study was undertaken of 101 consecutive patients who had undergone liver resection for colorectal metastases in two HPB centers. Preoperative demographic and premorbid data were gathered along with liver function tests and tumor markers. A subjective assessment of the surgical procedure was noted, and in-hospital morbidity and mortality were calculated. The effect of preoperative chemotherapy on short-term and long-term outcome was analyzed, and actuarial 1 and 3 year survival was determined. RESULTS: Patients who received neoadjuvant chemotherapy had a higher number of metastases (median 2, range 1-8 versus median 1, range 1-5; P = 0.019) and more had synchronous tumors (24 patients versus 8; P < 0.001). Overall morbidity was 37% and hospital mortality was 3.9%. Operative and in-hospital outcome was not influenced by chemotherapy. Long-term survival was worse in patients who had received preoperative chemotherapy (actuarial 3-year survival 62% versus 80%; P = 0.04). CONCLUSIONS: This study shows no evidence that neoadjuvant chemotherapy, and in particular oxaliplatin, increases the risk associated with liver resection for colorectal metastases. Long-term outcome is reduced in patients receiving preoperative chemotherapy, although they have more advanced disease.

Adult↗

PubMed2006

Intensive follow-up after liver resection for colorectal liver metastases: results of combined serial tumour marker estimations and computed tomography of the chest and abdomen - a prospective study.

The aim of the study was to prospectively evaluate an intensive follow-up programme using serial tumour marker estimations and contrast-enhanced computed tomography (CT) of the chest and abdomen in patients undergoing potentially curative resection of colorectal liver metastases. Seventy-six consecutive patients having undergone potentially curative resections of colorectal liver metastases in a single unit were followed up with a protocol of 3 monthly carcinoembryonic antigen and carbohydrate antigen 19-9 estimations and contrast-enhanced spiral CT of the chest, abdomen and pelvis for the first 2 years following surgery and 6 monthly thereafter. The median period of follow-up was 24 months (range 18-60). Recurrent tumour was classed as early if within 6 months of liver resection. Thirty-seven of the 76 patients (49%) developed recurrence on follow-up. Nineteen recurrences were in the liver alone (51%), 16 liver and extrahepatic (43%) and two extrahepatic alone (6%). Of the 19 patients with isolated liver recurrence, eight developed within 6 months of liver resection none of which were resectable. Of the 11 recurrences after 6 months, five (45%) were resectable. Of the 37 recurrences, CT indicated recurrence despite normal tumour markers in 19 patients. Tumour markers suggested recurrence before imaging in 12 and concurrently with imaging in 6. In the 12 patients who presented with elevated tumour markers before imaging, there was a median lag period of 3 months (range 1-21) in recurrence being detected on further serial imaging. Seventeen patients who developed recurrence had normal tumour markers before initial resection of their liver metastases. Of these 17, 10 (58%) had an elevation of tumour markers associated with recurrence. Over a median follow-up of 2 years following liver resection, the use of CT or tumour markers alone would have failed to demonstrate early recurrence in 12 and 18 patients respectively. A combination of tumour markers and CT detected significantly more (P < 0.05) recurrence than either modality alone. Tumour markers and CT should be used in combination in the follow-up of patients with resected colorectal liver metatases, including patients whose markers are normal at the time of initial liver resection.

Abdominal Neoplasms↗

PubMed2006

Remote ischaemic preconditioning of the hind limb reduces experimental liver warm ischaemia-reperfusion injury.

BACKGROUND: Direct ischaemic preconditioning of the liver reduces ischaemia-reperfusion injury (IRI). Remote ischaemic preconditioning (RIPC) of a limb has been shown to reduce IRI to the heart. This study determined the effect of brief remote ischaemia to the limb in reducing early liver warm IRI. METHODS: Twenty-eight male rabbits were allocated to four groups: sham operated, RIPC alone, IRI alone, and RIPC plus IRI. RIPC was induced in the leg with a tourniquet, before liver IRI, by three alternate cycles of 10 min ischaemia followed by 10 min reperfusion. Liver IRI was produced by total inflow occlusion for 25 min. Markers of liver injury and systemic and hepatic haemodynamics were measured for 2 h after reperfusion. RESULTS: At 2 h, IRI alone was associated with increased serum levels of aminotransferases, and reduced mean arterial blood pressure, hepatic blood flow and peripheral oxygen saturation. There was significant improvement in these variables in animals that had RIPC before liver IRI, and hepatic venous nitrate/nitrite levels were also significantly higher. CONCLUSION: In this experimental model RIPC appeared to reduce liver IRI.

Animals↗

PubMed2006

Rejection rates in a randomised trial of tacrolimus monotherapy versus triple therapy in liver transplant recipients with hepatitis C virus cirrhosis.

BACKGROUND: Reducing immunosuppression not only reduces complications but also may lessen recurrent hepatitis C virus (HCV) infection after liver transplantation. PATIENTS/METHODS: HCV-infected cirrhotic patients randomised to tacrolimus monotherapy (MT) or triple therapy (TT) using tacrolimus 0.1 mg/kg/day, azathioprine 1 mg/kg/day, and prednisolone 20 mg/day, tapering over 3 months. RESULTS: Twenty-seven patients (MT) and 29 (TT)--median follow up 661 days (range, 1-1603). Rejection episodes (protocol/further biopsies) within first 3 months and use of empirical treatment were evaluated. New rejection was diagnosed if repeat biopsy (5-day interval) did not show improvement. Treated rejection episodes: 20 MT (15 biopsy-proven) vs. 24 TT (21 biopsy-proven), with 19 (MT) vs. 24 (TT) methylprednisolone boluses. Overall: 35 episodes (MT) and 46 (TT). Fewer MT patients had histological rejection (70%) than TT patients (86%), with fewer episodes of rejection (18.5% vs. 10%), and more moderate rejection (22% vs. 41%). The MT group had higher early tacrolimus levels. Rates of renal dysfunction, retransplantation, and death were not significantly different. CONCLUSION: Tacrolimus monotherapy is a viable immunosuppressive strategy in HCV-infected liver transplant recipients.

Adult↗

PubMed2006

The role of glycine in hepatic ischemia-reperfusion injury.

Glycine is a non-essential amino acid which is cheap, easily available and relatively non-toxic. It is composed of a single carbon attached to an amino and a carboxyl group, with a molecular weight of 75. It is involved in the production of bile, nucleic acids, porphyrins and creatine phosphate. It is part of the normal human diet and is used clinically, as an irrigant solution in urological and gynaecological procedures. Glycine has broad spectrum anti-inflammatory, cytoprotective and immunomodulatory properties whose therapeutic role has largely been un-investigated. Since the demonstration of its cytoprotective effect on hypoxic cultured renal tubule cells, further research has established its mechanism of anti-inflammatory action, which depends on stimulation of glycine sensitive chloride channel receptors on the cell membrane. The mechanism of non-specific cytoprotective effect which is present even in chloride and calcium free media is not clear. However glycine is currently being used experimentally, in human liver transplant recipients and has been shown to be beneficial in animal models of ischemia-reperfusion injury (IRI) in liver and several other organs. This review addresses the properties of glycine, its mechanism of action and its role in modulating IRI with special reference to the liver, with the aim of stimulating translational research into the potential role of glycine as a pharmaceutical agent.

Animals↗

PubMed2006

Granular cell tumour of the bile duct mimicking distal cholangiocarcinoma: one case report and review of the literature.

Granular cell tumours (Gcts) are rare and most commonly located in the oral cavity, skin or subcutaneous tissue. The occurrence of this tumour in the biliary tract is rare. A 26 year old African man presented with abdominal pain and obstructive jaundice was found to have a localised distal bile stricture suggestive of cholangiocarcinoma which was resected by pylorus preserving partial pancreaticoduodenectomy. Histology revealed a gct of the intrapancreatic portion of the distal bile duct. GCT of the biliary tract are important as they are benign and can mimic bile duct cancers. A review of the 77 reported cases of Gcts of the biliary tract showed that the common bile duct is the most common site of occurrence (n=35). Only 2 cases in literature have been reported to be diagnosed preoperatively. Since there are no characteristic radiological features, the GCTs are difficult to differentiate from cholangiocarcinoma, sclerosing cholangitis or other benign tumors.

Journal Article↗

PubMed2005

Radioisotope bone scans in the preoperative staging of hepatopancreatobiliary cancer.

BACKGROUND: The aim of the study was to determine the value of radioisotope bone scans in the preoperative staging of patients with hepatopancreatobiliary (HPB) cancer. METHODS: Bone scanning was performed as part of a routine staging protocol in 402 consecutive patients with HPB cancer over a period of 5 years. Patients with positive bone scans underwent coned radiography, computed tomography with review on bone windows, or a bone biopsy. Bone scans were reviewed along with staging investigations, surgical and histological findings. Patients were followed for a minimum of 6 months. RESULTS: There were 171 patients with colorectal liver metastases, 106 with suspected pancreatic cancer, 47 with hepatocellular cancer, 52 with gallbladder cancer or cholangiocarcinoma, and 26 with other types of HPB cancer. Bone scans were negative in 377 patients (93.8 per cent) and positive in 25 patients (6.2 per cent). Of the 25 positive scans, 16 were falsely positive as a result of degenerative bone disease. Of nine patients with a true-positive bone scan, four had locally irresectable disease and four distant metastases. In only one patient did the bone scan result alone influence the decision to resect the HPB cancer. Overall sensitivity was 100 per cent, specificity 95.9 per cent, positive predictive value 36.0 per cent and negative predictive value 100 per cent. CONCLUSION: Bone scanning should not be included in the routine staging protocol for HPB cancer.

Aged↗

PubMed2005

Obstructive jaundice secondary to neuroendocrine tumour in a patient with von Recklinghausen's disease.

Neurofibromatosis type 1 (NF1) is an autosomal dominant genetic disorder, with variable clinical manifestations and unpredictable course, associated with an increased incidence of various tumours. Plexiform neurofibromas are hallmark lesions of NF1; they are slow-growing tumours, which account for substantial morbidity, including disfigurement and functional impairment, and may even be life-threatening. Neuroendocrine tumours (NETs), a rare diverse group of neoplasms, are occasionally associated with neurofibromatosis. Pancreatic NETs are tumours with an incidence of less than 1/100 000 population/year and complex patterns of behaviour, which often need complicated strategies for optimal management. We present the case of a young adult with NF1, having a unique concurrence of plexiform neurofibroma involving the liver with an ampullary NET, and we discuss step by step the management in a specialist centre.

Adult↗

PubMed2005

Endoscopic biliary stenting facilitates safe and early removal of T-tube in liver transplant patients.

AIM: Duct to duct anastomosis in orthotopic liver transplant (OLT) patients have been traditionally performed with a t-tube in place for 3 to 6 months. Following removal of the t-tube a high incidence of biliary leakage has been reported. METHODS: Prospective study to evaluate the role of endoscopic biliary stenting to facilitate early and uncomplicated t-tube removal. All patients with duct to duct biliary anastomosis who had a t-tube in situ, from January 1998 to December 2002 were included in this study. RESULTS: There were 29 patients eligible for the study. Eight patients were not included due to early death. A protocol t-tube cholangiogram was performed in all patients, (median 12 days; range 4-47 days) followed by an endoscopic stent insertion (median 37 days; range 20-55 days). The stent was removed later (median 84 days; range 45-133 days). All complications related to the procedure were noted. Stent insertion was successful in all cases. In 2 patients a second endoscopic retrograde cholangiopancreatography (ERCP) was necessary, either because of failure to cannulate the papilla or to reposition the stent. There was a patient who presented a biliary leak due to stent displacement requiring a laparotomy. There were two further biliary leaks, one of them in an asymptomatic patient, which were managed conservatively. In addition 1 patient developed a mild case of postERCP pancreatitis. CONCLUSIONS: In liver transplants patients with an end-to-end choledochostomy with a t-tube, endoscopic biliary stenting allows an early removal of the T tube, with few complications.

Adult↗

PubMed2004

Induction of adhesion molecule expression in liver ischaemia-reperfusion injury is associated with impaired hepatic parenchymal microcirculation.

BACKGROUND: Activated neutrophils may be important mediators in liver ischaemia-reperfusion injury (I/R). Adhesion of leucocytes to the endothelial cell surface is a result of activation of cell adhesion molecules. The aim of this study was to investigate the effect of I/R on the hepatic microcirculation (HM) and intercellular adhesion molecule (ICAM) 1 expression. METHODS: Four groups of six Sprague-Dawley rats underwent laparotomy for liver exposure. Group 1 acted as controls, and groups 2-4 underwent partial liver ischaemia for 30, 45 and 60 min respectively followed by reperfusion for 60 min. Flow in the HM was measured by laser Doppler flowmetry. Liver biopsies were taken at the end of the reperfusion period. ICAM-1 expression was assessed by immunohistochemistry (graded 0-3). RESULTS: Mean flow in the HM was significantly reduced with I/R (mean(s.e.m.) red cell flux 140(21), 52(3) and 43(2) with 30, 45 and 60 min ischaemia compared with control 230(17); all P < 0.001). ICAM-1 expression was significantly induced (mean(s.e.m.) 1.30(0.21), 2.50(0.22) and 2.80(0.17) with 30, 45 and 60 min ischaemia versus control 0.50(0.22); all P < 0.001). CONCLUSION: I/R produced a significant upregulation of ICAM-1 expression which correlated with impaired flow in the HM.

Animals↗

PubMed2004

Continuous infusion of N-acetylcysteine reduces liver warm ischaemia-reperfusion injury.

BACKGROUND: N-acetylcysteine (NAC) may modulate the initial phase (less than 2 h) of liver warm ischaemia-reperfusion (IR) injury but its effect on the late phase remains unclear. The present study investigated the role of NAC during the early and late phases in a rabbit lobar IR model. METHODS: Liver ischaemia was induced by inflow occlusion to the median and left liver lobes for 60 min, followed by 7 h of reperfusion. In the NAC group (n = 6), NAC was administered intravenously at 150 mg per kg over the 15 min before reperfusion and maintained at 10 mg per kg per h during reperfusion. In the IR group (n = 6), 20 ml 5 per cent dextrose was infused over the 15 min before reperfusion and continued at a rate of 10 ml/h. Animals in a sham operation group (n = 6) underwent laparotomy but no liver ischaemia. All animals were killed at the end of the experiment. RESULTS: Intracellular tissue oxygenation was improved after the second hour of reperfusion in animals treated with NAC compared with that in the IR group (P = 0.023). Hepatic microcirculation improved after 5 h of reperfusion (P = 0.036) and liver injury was reduced after 5 h, as indicated by alanine aminotransferase activity (P = 0.007) and indocyanine green clearance (uptake, P = 0.001; excretion, P = 0.032). CONCLUSION: The main protective effect of NAC becomes apparent 5 h after hepatic ischaemic injury.

Acetylcysteine↗

PubMed2004

Prospective study of contrast-enhanced computed tomography, computed tomography during arterioportography, and magnetic resonance imaging for staging colorectal liver metastases for liver resection.

BACKGROUND: This study compared the value of contrast-enhanced helical computed tomography (CT), CT during arterioportography (CTAP), and contrast-enhanced magnetic resonance imaging (MRI) for staging patients with colorectal liver metastases. METHODS: One hundred and twenty patients with known or suspected colorectal liver metastases were evaluated prospectively. MRI and CTAP were performed within 3 weeks of CT in patients with potentially resectable tumours. Results of imaging were compared with findings at surgery, intraoperative ultrasonography and histological examination. RESULTS: Twenty patients were not considered for liver resection following CT. The remaining 100 patients underwent CT and CTAP, 85 of whom had CT, CTAP and MRI. The sensitivity and specificity were 73.0 and 96.5 per cent for CT, 87.1 and 89.3 per cent for CTAP, and 81.9 and 93.2 per cent for MRI. Positive predictive values were 89.7, 87.5 and 87.5 per cent respectively. Receiver-operator characteristic analysis gave an accuracy on a segment-by-segment analysis of 0.73 for CT, 0.87 for CTAP and 0.82 for MRI. Combining information from CT and CTAP, CT and MRI, or all three modalities, did not significantly increase the percentage of patients staged correctly (71, 72 and 76 per cent respectively). CONCLUSION: The diagnostic accuracy of spiral CT, MRI and CTAP was similar. Combining modalities did not improve accuracy.

Adult↗

PubMed2004

Identification of cytochrome P450 enzymes in human colorectal metastases and the surrounding liver: a proteomic approach.

We describe the direct identification of multiple cytochrome P450 (CYP) enzymes in healthy and cancerous tissue. CYPs in human liver colorectal metastases were compared with those in the surrounding liver using a mass spectrometry-based proteomic approach. Nano-scale reversed phase liquid chromatography combined with electrospray ionisation tandem mass spectrometry has been used to identify CYPs with no pre-selection of the proteins anticipated. Fourteen distinct CYP enzymes from the subfamilies 1A, 2A, 2B, 2C, 2D, 2E, 3A, 4A, 4F, 8B and 27A were positively identified; 13 in the liver samples and 12 in the tumour tissue. It was found that three of the colorectal metastases expressed essentially the same drug-metabolising pattern of CYPs as the surrounding liver, whilst three tumour samples from different individuals showed no CYP expression. This was likely in at least one case to be due to low sample mass. The CYP expression profile in an individual tumour is likely to be an important determinant in predicting the outcome of cancer chemotherapy.

Adult↗

PubMed2004

Near-infrared spectroscopic assessment of mitochondrial oxygenation status--comparison during normothermic extracorporeal liver perfusion by buffer only or buffer fortified with washed red blood cells: an experimental study.

BACKGROUND: Use of marginal and non-heart-beating donors leads to an increased incidence of complications after clinical liver transplantation. Normothermic extracorporeal liver perfusion (NELP) may allow resuscitation and evaluation of such organs. Despite recent success in long-term liver preservation by NELP, no methods of organ evaluation have been defined. Mitochondrial cytochrome oxidase (Cyt Ox) levels reflect oxygen and substrate delivery, and hence ATP production at the cellular level. This study used near-infrared spectroscopy (NIRS) to measure Cyt Ox levels during NELP. METHODS: Livers retrieved from New Zealand white rabbits were immediately perfused in an extracorporeal circuit with oxygenated buffer (group A, n = 4) or red blood cell (RBC)-fortified buffer (group B, n = 4). Perfusion was continued for 3 hours at 37 degrees C pH 7.4, and perfusate was gassed with 95%O2/5%CO2 at 1 liter per minute. Cyt Ox levels were monitored continuously by NIRS and bile output was measured. RESULTS: Cyt Ox was reduced at the start of perfusion in both groups, but even more rapidly in the buffer-perfused group. After initial deterioration, Cyt Ox levels improved significantly (P < .05) with perfusion in the RBG-perfused group, but remained impaired in the buffer group 5.74 +/- 1.51 Deltamicromol/L and -25.77 +/- 21.94 Deltamicromol/L for groups B and A, respectively, at 180 minutes. Differences in bile output were not significant (19.33 +/- 9.50 and 25.00 +/- 16.81 micromol/min/100 g for groups B and A respectively). CONCLUSIONS: Cyt Ox levels may offer better viability markers than bile output. NIRS is a practical method to measure tissue oxygenation, and RBC-based perfusion provided better oxygenation during NELP.

Animals↗

PubMed2004

A model to study total hepatic ischemia-reperfusion injury.

BACKGROUND: Most experimental animal models for studying hepatic ischemia-reperfusion injury (IRI) involve partial or segmental ischemia of the liver or a portocaval shunt procedure to avoid mesenteric congestion. However, these do not reflect the global ischemia that occurs during liver transplantation. A rabbit model of total hepatic ischemia without a portocaval shunt is described. METHODS: Twenty male New Zealand white rabbits (3.5 +/- 0.3 kg) were allocated to four groups: group 1 (n = 5), sham-operated; group 2 (n = 5), 20-minute total hepatic ischemia; group 3 (n = 5), 25-minute total hepatic ischemia; and group 4 (n = 5), 30-minute total hepatic ischemia. Total hepatic ischemia was induced by occluding the portal inflow vessels (portal vein and artery) with an atraumatic vascular loop and were measurements taken for 2 hours during reperfusion. RESULTS: A total hepatic ischemia of 30 minutes caused severe liver injury resulting in cardiac arrest at 2 hours of reperfusion in all five animals due to metabolic acidosis. Twenty minutes of total ischemia was tolerated and did not produce significant liver injury. Twenty-five minutes of total ischemia was tolerated but at 2 hours of reperfusion, resulted in significant liver injury (68 +/- 41, 283.0 +/- 20.5, and 835.2 +/- 52.7 U/L) compared with the sham-operated group (serum ALT, 25.4 +/- 2.7; serum AST, 47.4 +/- 3.0; serum LDH, 307.6 +/- 44.4 U/L; P < .003). CONCLUSIONS: Rabbits can tolerate 25 minutes of total hepatic ischemia without a portosystemic shunt. This 25-minute ischemia model simulates operative conditions during liver transplantation and will be valuable in studies modulating IRI.

Alanine Transaminase↗

PubMed2004

A comparison of bile composition from heart-beating and non-heart-beating rabbit organ donors during normothermic extracorporeal liver perfusion: experimental evaluation using proton magnetic resonance spectroscopy.

BACKGROUND: Organs retrieved from marginal and non-heart-beating donors (NHBDs) have sustained variable degrees of preretrieval damage that result in an increased incidence of complications. Normothermic extracorporeal liver perfusion (NELP) provides an opportunity to evaluate and resuscitate such organs. The aim of this study was to identify markers of ischemic injury in bile during perfusion of livers from heart-beating donors (HBDs) and NHBDs. METHODS: Livers were retrieved from New Zealand white rabbits. The HBD group (n=4) had no in situ warm ischemia before retrieval and the NHBD group (n=4), 45 minutes of in situ warm ischemia before liver retrieval. After 40 minutes of postretrieval cold ischemia, all livers were dual vessel reperfused, normothermically with oxygenated buffer solution supplemented with rabbit red blood cells, for 6 hours. Bile was collected and examined with 1HMRS. RESULTS: Perfusion bile from HBD group showed an increased concentration of bile acids, lactate, glucose, and phosphatidylcholine, but a decreased concentration of acetate as compared to retrieval bile. This trend was further enhanced in NHBD group. The mean +/- SD (in micromol/L) were bile acids (10.48 +/- 2.8 vs 26.05 +/- 12.1 vs 44.5 +/- 44.5), lactate (10.66 +/- 4.5 vs 14.66 +/- 5.2 vs 13.22 +/- 1.8), glucose (5.37 +/- 2 vs 21.2 +/- 5.0 vs 29.09 +/- 15.3), phosphatidylcholine (0.21 +/- 0.02 vs 5.57 +/- 1.7 vs 6.42 +/- 0.3), and acetate (1.8 +/- 0.5 vs 0.39 +/- 0.1 vs 0.38 +/- 0.09) for retrieval bile, HBD perfusion bile, and NHBD perfusion bile, respectively. One animal from each group did not produce any bile during perfusion. CONCLUSIONS: 1HMRS of biliary constituents revealed differences with the type of ischemia. These indices may be potential markers of the extent of warm ischemic injury and the functional activity of an extracorporeally perfused liver.

Animals↗

PubMed2003

Strategies to increase the resectability of liver metastases from colorectal cancer.

Liver resection can provide long-term survival and cure for patients with colorectal liver metastases but is feasible in only 15-25% of patients. In the last few years several major developments have contributed to increase this resectability rate. Neo-adjuvant chemotherapy can provide response rates as high as 50%, allowing surgery in about 10-15% of patients initially deemed unresectable. Patients requiring extensive liver resections with an anticipated small residual liver volume can undergo portal vein embolization to reduce the risk of postoperative liver failure by inducing hypertrophy of the remnant liver. Extensive bilobar disease can be treated by two-stage hepatectomy, with an interval to allow liver regeneration. Ablation techniques can be combined with hepatic resection to reduce local recurrence from incomplete surgical resection margins or to destroy contralateral tumor deposits. Finally, for patients with tumors involving the inferior vena cava or the hepatic veins, in which conventional resection is not feasible, in situ hypothermia or bench resection with reimplantation are suitable for very selected patients. Downstaging strategies may increase the resectability rate of colorectal liver metastases by over 20%.

Catheter Ablation↗

PubMed2003

Telemedicine in surgery.

BACKGROUND: Telemedicine is influencing surgical training, allows mentoring, proctoring and teleconferencing, and is increasingly being applied to carry out remote surgical procedures. A systematic review of the telemedicine systems available, along with a critical appraisal of their application, potential and limitations in the surgical field, has been undertaken. METHOD: Medline, Ovid and internet searches were carried out using the keywords 'telesurgery', 'telepresence surgery' and 'telemedicine and surgery', along with hand searches of the two peer-reviewed telesurgery journals. RESULTS: Telementoring and teleconferencing have been used widely for surgical teaching and training. Two clinical telesurgery systems are currently available and have been a trial in patients undergoing a variety of operations including cholecystectomy, coronary artery bypass, prostatectomy and gastroplasty. Most studies have reported successful outcomes but with prolonged operating times. In 2002 the first long-distance telesurgery procedure was successfully performed. CONCLUSION: Telemedicine has huge potential to alter surgical practice but improvements are required in telesurgical technology with respect to tactile feedback, instrumentation, telecommunication speed and availability. Issues of liability, legislation, cost and benefit require clarification. The future of telemedicine in surgery may lie in facilitating complex minimally invasive techniques.

Humans↗