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R Ellgass

Publications and source records attributed to R Ellgass.

2 recordsLinked to original sources
PubMed1999

Use of the voice-controlled and computer-assisted surgical system ZEUS for endoscopic coronary artery bypass grafting.

OBJECTIVE: With the aim of performing a completely endoscopic coronary bypass anastomosis, we have undertaken an experimental and clinical study using robotic instrumentation and voice-controlled camera guidance. METHODS: The ZEUS Robotic Surgical System (Computer Motion Inc, Goleta, Calif) consists of three interactive robotic arms and a control unit, allowing the surgeon to move the instrument arms in a scaled down mode. The third arm (AESOP, Computer Motion) positions the endoscope via voice control. PHASE I: In a phantom model, vascular grafts were anastomosed to the left anterior descending coronary artery (LAD) of 50 pig hearts with either 2- or 3-dimensional visualization. PHASE II: In 6 dogs (FBI 20-25 kg) the left internal thoracic artery (LITA) was harvested endoscopically. Then the animals were placed on an endovascular cardiopulmonary bypass system (Port-Access, Heartport, Inc, Redwood City, Calif). Anastomosis of the LITA to the LAD was performed endoscopically with the telemetric ZEUS instruments. Flow rates through the LITA were measured by Doppler analysis. PHASE III: Two patients were operated on with the ZEUS system. After endoscopic harvesting of the LITA and cardiopulmonary bypass with the Port-Access system, the bypass graft (LITA-LAD) was anastomosed endoscopically with the ZEUS system through three thoracic ports. RESULTS: In the dry laboratory, the time range required for the robotically assisted coronary anastomosis was 35 to 60 minutes with 2-dimensional visualization and 16 to 32 minutes with 3-dimensional visualization. In the animal experiments, the median time for endoscopic harvesting of the LITA was 86 minutes (range 56-120 minutes) and for the anastomosis, 42 minutes (range 35-105 minutes); flow rates through the LITA ranged between 22 and 45 mL/min. In the clinical cases, preparation times for the LITA were 83 and 110 minutes, respectively, and anastomosis times, 42 and 40 minutes, respectively. Doppler flow rates measured 125 and 85 mL/min, respectively. Both patients had an uneventful follow-up angiogram and postoperative course. CONCLUSIONS: With sophisticated robotic technology, a completely endoscopic anastomosis of the LITA to the LAD is possible, allowing technically precise operations within acceptable time limits.

Anastomosis, Surgical↗
PubMed1999

3D-visualization improves the dry-lab coronary anastomoses using the Zeus robotic system.

BACKGROUND: Robotic surgical instruments enable quick and precise movements and may allow complete endoscopic coronary artery bypass grafting. However, cardiac surgeons will have to become familiar with this technology and endoscopic viewing. We present our training program with special focus on 2D- and 3D-visualization. METHODS: A thoracic skeleton, covered with a neoprene suit, served as model for the chest wall. Either a glove, fixed on a metal plate, or a pig heart were placed inside for training. On the glove, a suture line consisting of two lines of 16 points each, with a distance of 2 mm between each point, was stamped. On the pig heart, the LAD was prepared and incised; subsequently an anastomosis was done using the dissected right coronary artery as a graft. The time required was measured for both models. For suturing, the Zeus System (Computer Motion, Goleta, CA) was used and the third robotic arm positioned the endoscopic camera. The scopes were connected to a 3D-camera and the picture was displayed on a headset with two integrated monitors. Visualization was set to either 2D or 3D. Three surgeons were involved in the study. Each one did at least 12 anastomoses on 2D and 3D. RESULTS: The three surgeons involved showed a clear and rapid learning curve. The times required for the suture line decreased from 12.5 +/- 1.6 to 8.5 +/- 0.5 minutes with 2D and from 11.9 +/- 5.4 to 7.8 +/- 0.5 minutes for 3D respectively. This decrease did reach statistical significance (p = 0.03). In the pig heart model, the anastomosis times decreased from 33.2 +/- 8.4 to 15.7 +/- 0.3 minutes with 3D-visualization, and from 36.2 +/- 2.2 to 29.5 +/- 3.3 minutes with 2D. The decrease in anastomosis time did again reach significance (p = 0.025). At the end of the study, the times achieved with 2D-visualization were significantly longer than those with 3D (p = 0.01). CONCLUSIONS: A surgical training program is mandatory to become familiar with these new technologies. Both models showed learning curves over an acceptable time course. 3D-visualization facilitated quick and precise movements, thus resulting in shorter anastomosis times.

Anastomosis, Surgical↗