Laboratory Unit for Computer Assisted Surgery is a system used for virtual

surgical planning Surgical planning is the preoperative method of pre-visualising a surgical intervention, in order to predefine the surgical steps and furthermore the bone segment navigation in the context of computer-assisted surgery. The surgical planning is mos ...

. Starting with 1998, LUCAS was developed at the University of Regensburg, Germany, with the support of the Carl Zeiss Company. The resulting surgical planning is then reproduced onto the patient by using a

navigation system A navigation system is a computing system that aids in navigation. Navigation systems may be entirely on board the vehicle or vessel that the system is controlling (for example, on the ship's bridge) or located elsewhere, making use of radio or othe ...

. In fact, LUCAS is integrated into the same

platform Platform may refer to: Technology * Computing platform, a framework on which applications may be run * Platform game, a genre of video games * Car platform, a set of components shared by several vehicle models * Weapons platform, a system or ...

together with the Surgical Segment Navigator (SSN), the Surgical Tool Navigator (STN), the Surgical Microscope Navigator (SMN) and the 6 DOF Manipulator (or, in German, "Mehrkoordinatenmanipulator" - MKM), also from the Carl Zeiss Company. __TOC__

Workflow

Data from separate bidimensional slices generated by a CT or

MRI Magnetic resonance imaging (MRI) is a medical imaging technique used in radiology to form pictures of the anatomy and the physiological processes of the body. MRI scanners use strong magnetic fields, magnetic field gradients, and radio waves ...

scan are uploaded into the LUCAS system. The resulting

dataset A data set (or dataset) is a collection of data. In the case of tabular data, a data set corresponds to one or more database tables, where every column of a table represents a particular variable, and each row corresponds to a given record of the ...

is then processed, in order to eliminate

image noise Image noise is random variation of brightness or color information in images, and is usually an aspect of electronic noise. It can be produced by the image sensor and circuitry of a scanner or digital camera. Image noise can also originate in ...

, and to enhance the anatomical contours and also the general contrast of the images. The next step is to create a virtual 3D model from the gathered collection of 2D images. The bone segment that is to be repositioned is marked, on the 3D grid reconstructed model; then, the actual repositioning of that bone segment is done on the virtual model, until the optimal anatomical position is obtained. The criteria for the optimal position of the bone segment are: symmetry with the opposite side, the continuity of the normal bone contours, or the normal volume of an anatomical region (such as the

Orbit In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as a p ...

. Afterwards, a textured final image is rendered. The calculated vectors for the bone segment repositioning, together with the whole virtual model are finally transferred to the Surgical Segment Navigator.

References

Marmulla R, Niederdellmann H: ''Surgical Planning of Computer Assisted Repositioning Osteotomies'', Plast Reconstr Surg 104 (4): 938-944, 1999
{Dead link, date=February 2020 , bot=InternetArchiveBot , fix-attempted=yes Oral and maxillofacial surgery Medical software Radiology Tomography Computer-assisted surgery