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To relieve the surgeon during functional endoscopic endonasal sinus surgery (FESS), the endoscope should be guided by autonomous robot assistance. The surgeon will thus have two hands free for suctioning and manipulation during FESS.With a force/torque sensor mounted on the endoscope, we measured forces in six degrees of freedom in five cadaver heads and in 20 actual endoscopic sinus procedures. On the cadaver heads we performed complete endoscopic endonasal dissection of all paranasal sinuses. All forces at the endoscope were monitored continuously.The mean forces occurring at the endoscope were 3.2 N. There were only slight differences between the in vivo and ex vivo data. We measured peak forces up to 25.2 N. In 95% of all cases, forces were lower than 7 N.Forces up to 7 N are sufficient for endoscopic guidance during FESS. Peak forces are distinctive for endoscopic guidance by humans and could be optimised by sensor-based intraoperative robot guidance. Higher forces are required for surgical endoscopy of the frontal and maxillary sinuses compared with the ethmoid sinuses.

We present a surgical telemanipulator system supporting long bone fracture reduction procedures. This paper gives an overview of the robotic system developed by our working group and describes a possible workflow for telemanipulated fracture reduction. The concepts enabling an intuitive control of the robot using a joystick with force feedback as input device are also described.With our robotic set-up we performed a test series, in order to evaluate the achievable reposition accuracies and operation times. 11 femoral shaft fractures in seven human donors have been reduced with the telemanipulator and the results have been compared with those achieved by conventional manual and navigated manual repositions.All fractures in our test series could be reduced successfully with the telemanipulator, achieving a mean rotational deviation of 4.9 degrees in axial direction and 2.5 degrees and 3.5 degrees in AP and lateral direction. We could find no statistically significant difference between the accuracies achieved by the telemanipulator and those achieved by the two manual procedures. The image intensifier usage times of our telemanipulated repositions were conspicuously lower compared to the conventional manual repositions and statistically significant lower compared to the navigated repositions.We could show that robot-assisted fracture reduction is possible, yielding good accuracies and a conspicuous reduction of X-ray irradiation. However, we also show the limitations regarding reposition accuracies of telemanipulated fracture reduction when it is based on 2D X-ray imaging only. From the combination of 3D imaging, automated computation of the reduction parameters, and automated force/torque guided reduction by the robot we expect to overcome these limitations in our future work.

A 61-year-old man with Hodgkin lymphoma (mixed type), with lymph node manifestations and extranodal and bone marrow involvement in both supra- and infradiaphragmatic locations (stage 4), had dyspnea and tachycardia on echocardiography. There were pleural and pericardial effusions and thickening of the epicardium and pericardium. These findings and computed tomographic findings were suspicious for manifestations of Hodgkin lymphoma. The pericardial findings were demonstrated on F-18 fluorodeoxyglucose positron emission tomographic imaging.

Colorectal carcinoma is the third most common cancer in the United States, accounting for 15% of malignancies. The liver is the most common site of metastasis. Approximately 25% of patients have hepatic metastases at the time of presentation and two-thirds eventually develop them. The presence of hepatic metastases has a major influence on prognosis. Survival in untreated patients with colorectal cancer metastatic to the liver varies from 1 to 22 months and is a function of the extent of hepatic disease at the time of presentation.1 Complete surgical resection of liver metastases is the only curative therapy but is feasible for only a few patients who have solitary or unilobar metastasis. Conventional intravenous bolus chemotherapy (e.g., 5-fluorouracil) yields response rates of only 10% to 30%.2

From various papers we know trigonometric equations and their solutions — called prototype equations hereafter− which successfully can be employed to compute closed form solutions of inverse robot kinematics. In this paper we show, that the prototype equations known up to now are not sufficient to compute the inverse solution of some arms. In addition we propose new prototype equations whose solutions are equivalent to the solutions of polynomials of degree two and four and show how these new prototypes can be employed successfully to some arms. The last part of the paper gives an insight to the implementation of some of these prototypes in our Symbolic Kinematics Inversion Program SKIP.

This paper presents a universal test data generator for the systematic evaluation of inverse kinematics systems. A Denavit-Hartenberg parameter based kinematics description language LDL has been developed; it is used as input language for the generator. LDL allows the expression of kinematic and geometric constraints, which have to be satisfied by the resulting generated kinematics. Moreover, it is possible to generate certain well-known classes of manipulators. Combining the basic features and different kinds of constraints, a LDL program can be used to define and to generate classes of manipulators. >

This paper describes a new method to recognize 3d polyhedral objects on the basis of single 2d images. The recognition is performed by transforming the captured image into the Hough space and a subsequent interpretation in this domain. The new technique is capable of splitting up more complex scenes into their components and of decomposing these into object primitives stored in an extendable object library. The method is exceptionally robust with respect to noise and the data structures of the objects in Hough space are very compact and easy to handle.