Biomedical subjects

Kai Matthes

Publications and source records attributed to Kai Matthes.

7 recordsLinked to original sources

PubMed2006

EUS-guided injection of paclitaxel (OncoGel) provides therapeutic drug concentrations in the porcine pancreas (with video).

BACKGROUND: OncoGel (ReGel/paclitaxel) is an intralesional injectable formulation of the chemotherapeutic drug, paclitaxel, for local tumor management. OBJECTIVE: The aim of this study was to determine if a minimally invasive EUS-guided injection of paclitaxel, bound to a thermosensitive gel carrier, would lead to therapeutic tissue concentrations of the chemotherapeutic agent in the porcine pancreas. DESIGN: Eight Yorkshire breed pigs were sedated by general anesthesia and OncoGel was injected, under EUS-guidance, with a 22-gauge needle into the tail of the pancreas. MAIN OUTCOME MEASUREMENTS: During the 7-day (n = 4) or 14-day (n = 4) observational period, the animals were monitored by serum levels of amylase and lipase, and by a CT on day 4. The outcome was determined by gross and microscopic evidence of inflammation of the pancreas, clinical tolerance, and quantitation of tissue paclitaxel concentrations. RESULTS: Eight pigs underwent injection of 1, 2, 3, or 4 mL OncoGel (6 mg paclitaxel per 1 mL OncoGel) (n = 2 per group). An intrapancreatic hyperechoic focus, with an average diameter of 2.1 +/- 0.8 cm, was visible by EUS, and a hypodense area in the tail of the pancreas was visible by contrast CT. Clinically, the animals appeared to tolerate the procedure without sequelae. Blood levels of amylase and lipase were normal. At euthanasia, a depot of OncoGel, with an average diameter of 14.7 +/- 5.0 mm), was located both grossly and histologically in the pancreatic tail. After 14 days, clinically significant tissue concentrations of paclitaxel were detected at a distance of 30 to 50 mm from the depot in the animals that underwent an injection of 3 and 4 mL of the agent (n = 2). CONCLUSIONS: The EUS-guided injection of OncoGel into the pancreas of the pig provided high and sustained localized concentrations of paclitaxel. This technique is a potential minimally invasive local treatment option for unresectable pancreatic tumors.

Animals↗

PubMed2006

EUS staging of upper GI malignancies: results of a prospective randomized trial.

BACKGROUND: Electronic 270 degrees transverse-array EUS (TA-EUS) provides high-quality cross-sectional images but cannot guide FNA. Linear EUS (L-EUS) provides longitudinal images of malignancies and the ability to guide FNA. OBJECTIVE: We conducted a prospective randomized comparison of TA-EUS and L-EUS for the staging of upper-GI (UGI) malignancies. DESIGN: Forty-three patients underwent L-EUS immediately followed by TA-EUS (N = 27, 63%) or TA-EUS immediately followed by L-EUS (N = 16, 37%). PATIENTS: Forty-three subjects (mean age, 64 years; 37 men) with an UGI malignancy (4 stomach and 38 esophageal) were evaluated with both TA-EUS and L-EUS. INTERVENTIONS: Abnormal lymph nodes were sampled by FNA for cytology. RESULTS: There was agreement on the T stage by linear and radial techniques in 38 of 43 subjects (88%). Twenty-seven of 43 patients (63%) had abnormal lymph nodes by linear or transverse-array imaging. L-EUS demonstrated 66 abnormal lymph nodes in 27 subjects (average of 2.4 nodes/subject). TA-EUS demonstrated 90 abnormal lymph nodes in 27 subjects (average of 3.3 nodes/subject, P = .009, compared with L-EUS). In 16 of the 27 subjects, an FNA was performed, which was positive in 13 cases (81%) and negative in 3 cases (10%) for malignancy. CONCLUSIONS: TA-EUS and L-EUS provide similar results of T staging of UGI malignancies. However, the number of abnormal lymph nodes detected by TA-EUS was more than by L-EUS. These findings suggest that radial or transverse-array EUS imaging should be the primary method for staging of UGI malignancies.

Aged↗

PubMed2006

The Neo-Papilla: a new modification of porcine ex vivo simulators for ERCP training (with videos).

BACKGROUND: Computer simulators, live pigs, and ex vivo porcine simulators are used for training in ERCP. The location of the porcine biliary orifice in the proximal duodenum is dissimilar to human anatomy, making the endoscopy experience less realistic. In addition, in native porcine anatomy, the pancreatic duct enters the duodenum distal to the biliary orifice, limiting the teaching of pancreatic techniques and selective duct cannulation. OBJECTIVE: To overcome these limitations, we aimed to construct a Neo-Papilla that could be incorporated into an ex vivo model. DESIGN: We attached chicken heart tissue to the porcine duodenum, with integrated porcine arteries that resembled an artificial common bile duct and a pancreatic duct. SETTING: The simulator was presented and evaluated at 2 major GI endoscopy conferences. MAIN OUTCOME MEASUREMENTS: The feasibility and the realism of this prototype was tested by 9 recognized ERCP experts who rated this model in comparison to other teaching models for ERCP by recollection of prior experience. RESULTS: The Neo-Papilla was more prominent and more distally located than the native porcine papilla. The experts rated this modification superior to existing models in its usefulness as an educational tool. LIMITATIONS: Pilot study. CONCLUSIONS: We demonstrated the technical feasibility of a real-tissue Neo-Papilla modification of porcine ex vivo simulators, more closely approximating the natural anatomy. This new model should facilitate ERCP training. Formal validation studies are warranted.

Ampulla of Vater↗

PubMed2006

Simulator training in endoscopic hemostasis.

Simulation of upper gastrointestinal (GI) hemorrhage provides the opportunity to practice endoscopic hemostasis without the risk of patient harm and time limitations. Various models have been developed to simulate an acute bleeding source in the upper GI tract to evaluate the feasibility of new endoscopic devices or to practice interventional techniques in a calm and controlled environment. Increasingly available ex vivo models provide this opportunity without the ethical concerns involved with live-animal courses. Validation studies have proven acceptance of ex vivo models and improved clinical performance by repetitive training using these models.

Animals↗

PubMed2006

The complementary Erlangen active simulator for interventional endoscopy training is superior to solely clinical education in endoscopic hemostasis--the French training project: a prospective trial.

BACKGROUND: The Erlangen Active Simulator for Interventional Endoscopy (EASIE) using ex-vivo porcine organs was introduced in 1997. The present study should analyze whether repeated EASIE simulator training in endoscopic hemostasis led to superior performance compared with a traditionally educated group. The results were compared with a similar project in New York. METHODS: Thirty-five French GI fellows were enrolled. Baseline skills evaluation was performed in four disciplines (manual skills, injection/coagulation, clip application and variceal ligation) using the compactEASIE-simulator equipped with an upper gastrointestinal organ package for bleeding simulation. The same, translated evaluation forms (from the prior New York project) were used. Subsequently, fellows were randomized into group A (n=17, only clinical education) and group B (n=18, additional three simulator trainings). Group B was trained the next day and after 4 and 7 months by experts of the French Society of Gastrointestinal Endoscopy. Both groups performed routine and emergency endoscopies at their home hospitals during the study period. Both groups were re-evaluated blindly after 9 months. RESULTS: The learning curve for group B showed a significant improvement in all disciplines (P<0.004) whereas group A improved significantly in only two of four disciplines at blinded final evaluation (manual skills P=0.02, injection/coagulation P=0.013). The direct comparison of groups B and A at blinded final evaluation showed significantly superior ratings for group B in all disciplines (P<0.006) and significantly shorter performance times in two disciplines (P=0.016 each). The comparison with the similar 'New York project' revealed that preexisting differences in skills were adjusted by the training. CONCLUSION: Complementary trainings (three workshops in 7 months) in endoscopic hemostasis using the compactEASIE improved skills compared with a solely clinical education. The results of the 'New York project' were confirmed and benefits were independent from the medical educational system.

Animals↗

PubMed2005

Efficacy and costs of a one-day hands-on EASIE endoscopy simulator train-the-trainer workshop.

BACKGROUND: The efficacy of an intensive hands-on training in endoscopic hemostasis on the compactEASIE simulator has been previously demonstrated in a randomized prospective trial. In the current study, we evaluated how quickly and effectively new tutors, without simulator training experience, are able to acquire teaching skills in endoscopic hemostasis. METHODS: Five tutors with prior Erlangen Active Simulator for Interventional Endoscopy (EASIE) teaching experience instructed 7 endoscopists without prior EASIE experience on how to teach when using the model. These new tutors then independently conducted a workshop for 8 fellows in 4 hemostasis techniques. Results were compared with a historical control trained similarly by experienced tutors. Two one-day workshops in endoscopic hemostasis on the compactEASIE ex vivo endoscopy simulator were conducted in a category A hospital in New York City, New York. Skill scores at the end of training were compared with baseline skills assessments, and qualitative ratings of the new tutors were obtained from both the trainees and the experienced tutors. RESULTS: Significant improvement was achieved by the fellows in all 4 skills areas. Both the expert tutors and the trainees consistently rated the teaching skill of the new tutors highly. Fellows' skill acquisition using new tutors was of similar magnitude to that achieved in the prior EASIE trial using experienced trainers teaching the fellows. CONCLUSIONS: It is feasible to conduct an effective EASIE train-the-trainer course in one day. Tutors trained in this manner are able to provide a similar educational experience with objective improvement in trainee skill to experts who have conducted many hands-on workshops.

Clinical Competence↗

PubMed2005

Training with the compactEASIE biologic endoscopy simulator significantly improves hemostatic technical skill of gastroenterology fellows: a randomized controlled comparison with clinical endoscopy training alone.

BACKGROUND: The Erlangen Active Simulator for Interventional Endoscopy (EASIE) was introduced in 1997 for interventional endoscopy training. compactEASIE developed in 1998 is a modified, light-weight version of the original model. Objective evidence of the benefits of training with these models is limited. A randomized controlled study, therefore, was conducted to compare the effects of intensive 7-month, hands-on training in hemostatic techniques by using the compactEASIE model (in addition to clinical endoscopic training) vs. pure clinical training in endoscopic hemostatic methods. METHODS: Thirty-seven fellows in gastroenterology in New York City area training programs were enrolled. Baseline skills were assessed on the simulator for the following techniques: manual skills, injection and electrocoagulation, hemoclip application, and variceal ligation. Twenty-eight fellows were then randomized into two comparable groups. Those randomized to Group A received purely clinical training in endoscopic hemostatic techniques at their hospitals. Those in Group B, in addition, were trained by experienced tutors in 3 full-day hemostasis workshops over 7 months. Both groups underwent a final evaluation on the compactEASIE simulator conducted by their tutors and additional evaluators who were blinded to the method of training. Initial and final evaluation scores were compared for each group and between groups. Outcomes of actual clinical hemostatic procedures performed during the study period also were analyzed. RESULTS: Ten of 14 fellows randomized to Group A (standard training) and 13 of 14 in Group B (intensive training) returned for the final evaluation. For Group B, scores for all techniques were significantly improved. In Group A, a significant improvement was noted for variceal ligation alone. CONCLUSIONS: compactEASIE simulator training (3 sessions over 7 months), together with clinical endoscopic training resulted in objective improvement in the performance by fellows of all 4 endoscopic hemostatic techniques, whereas significant improvement was noted for variceal ligation alone for fellows who had standard clinical training. In clinical practice, fellows who had intensive simulator/clinical training had a significantly higher success rate and a nonsignificant reduction in the frequency of occurrence of complications.

Animals↗