Guoyan Zheng's Publications List

Development of an auditory implant manipulator for minimally invasive surgical insertion of implantable hearing devices.

2011-03-29T07:45:56Z

To present the auditory implant manipulator, a navigation-controlled mechanical and electronic system which enables minimally invasive ('keyhole') transmastoid access to the tympanic cavity.

C Stieger, M Caversaccio, A Arnold, G Zheng, J Salzmann, D Widmer, N Gerber, M Thurner, C Nauer, Y Mussard, M Kompis, L P Nolte, R Häusler, S Weber (2011) J Laryngol Otol 125: 3 262-270

Scaled, patient-specific 3D vertebral model reconstruction based on 2D lateral fluoroscopy.

2011-03-29T08:02:55Z

BACKGROUNDS: Accurate three-dimensional (3D) models of lumbar vertebrae are required for image-based 3D kinematics analysis. MRI or CT datasets are frequently used to derive 3D models but have the disadvantages that they are expensive, time-consuming or involving ionizing radiation (e.g., CT acquisition). An alternative method using 2D lateral fluoroscopy was developed. MATERIALS AND METHODS: A te...

Guoyan Zheng, Lutz-P Nolte, Stephen J Ferguson (2011) Int J Comput Assist Radiol Surg :

An integrated approach for reconstructing a surface model of the proximal femur from sparse input data and a multi-resolution point distribution model: an in vitro study.

2011-03-29T07:45:25Z

Accurate reconstruction of a patient-specific surface model of the proximal femur from preoperatively or intraoperatively available sparse data plays an important role in planning and supporting various computer-assisted surgical procedures.

Guoyan Zheng, Steffen Schumann, Miguel A González Ballester (2010) Int J Comput Assist Radiol Surg 5: 1 99-107

Assessing the accuracy factors in the determination of postoperative acetabular cup orientation using hybrid 2D-3D registration.

2011-03-29T07:45:25Z

Single standard anteroposterior radiograph-based methods for measuring cup orientation following total hip arthroplasty (THA) are subject to substantial errors if the individual pelvic orientation with respect to X-ray plate is not taken into consideration. Previously, we proposed to use a hybrid 2D-3D registration scheme to determine the postoperative acetabular cup orientation and developed an o...

Guoyan Zheng (2010) J Digit Imaging 23: 6 769-779

Computer assisted determination of acetabular cup orientation using 2D-3D image registration.

2011-03-29T07:45:25Z

2D-3D image-based registration methods have been developed to measure acetabular cup orientation after total hip arthroplasty (THA). These methods require registration of both the prosthesis and the CT images to 2D radiographs and compute implant position with respect to a reference. The application of these methods is limited in clinical practice due to two limitations: (1) the requirement of a c...

Guoyan Zheng, Xuan Zhang (2010) Int J Comput Assist Radiol Surg 5: 5 437-447

Effective incorporating spatial information in a mutual information based 3D-2D registration of a CT volume to X-ray images.

2011-03-29T07:45:25Z

This paper addresses the problem of estimating the 3D rigid poses of a CT volume of an object from its 2D X-ray projection(s). We use maximization of mutual information, an accurate similarity measure for multi-modal and mono-modal image registration tasks. However, it is known that the standard mutual information measures only take intensity values into account without considering spatial informa...

Guoyan Zheng (2010) Comput Med Imaging Graph 34: 7 553-562

Statistical shape model-based reconstruction of a scaled, patient-specific surface model of the pelvis from a single standard AP x-ray radiograph.

2011-03-29T07:45:25Z

The aim of this article is to investigate the feasibility of using a statistical shape model (SSM)-based reconstruction technique to derive a scaled, patient-specific surface model of the pelvis from a single standard anteroposterior (AP) x-ray radiograph and the feasibility of estimating the scale of the reconstructed surface model by performing a surface-based 3D/3D matching.

Guoyan Zheng (2010) Med Phys 37: 4 1424-1439

Validation of statistical shape model based reconstruction of the proximal femur--A morphology study.

2011-03-29T07:45:25Z

Seventeen bones (sixteen cadaveric bones and one plastic bone) were used to validate a method for reconstructing a surface model of the proximal femur from 2D X-ray radiographs and a statistical shape model that was constructed from thirty training surface models. Unlike previously introduced validation studies, where surface-based distance errors were used to evaluate the reconstruction accuracy,...

Steffen Schumann, Moritz Tannast, Lutz-P Nolte, Guoyan Zheng (2010) Med Eng Phys 32: 6 638-644

Statistically deformable 2D/3D registration for estimating post-operative cup orientation from a single standard AP X-ray radiograph.

2011-03-29T07:45:25Z

The widely used procedure of estimating post-operative cup orientation based on a single standard AP X-ray radiograph is known inaccurate, largely due to the wide variability in individual pelvic orientation relative to X-ray plate. CT-based 2D/3D rigid image registration methods have been developed to measure post-operative cup orientation. Although encouraging results have been reported, their e...

Guoyan Zheng (2010) Ann Biomed Eng 38: 9 2910-2927

HipMatch: an object-oriented cross-platform program for accurate determination of cup orientation using 2D-3D registration of single standard X-ray radiograph and a CT volume.

2011-03-29T07:45:25Z

The widely used procedure of evaluation of cup orientation following total hip arthroplasty using single standard anteroposterior (AP) radiograph is known inaccurate, largely due to the wide variability in individual pelvic orientation relative to X-ray plate. 2D-3D image registration methods have been introduced for an accurate determination of the post-operative cup alignment with respect to an ...

Guoyan Zheng, Xuan Zhang, Simon D Steppacher, Stephen B Murphy, Klaus A Siebenrock, Moritz Tannast (2009) Comput Methods Programs Biomed 95: 3 236-248

A 2D/3D correspondence building method for reconstruction of a patient-specific 3D bone surface model using point distribution models and calibrated X-ray images.

2011-03-29T07:45:25Z

Constructing a 3D bone surface model from a limited number of calibrated 2D X-ray images (e.g. 2) and a 3D point distribution model is a challenging task, especially, when we would like to construct a patient-specific surface model of a bone with pathology. One of the key steps for such a 2D/3D reconstruction is to establish correspondences between the 2D images and the 3D model. This paper presen...

Guoyan Zheng, Sebastian Gollmer, Steffen Schumann, Xiao Dong, Thomas Feilkas, Miguel A González Ballester (2009) Med Image Anal 13: 6 883-899

Robust automatic detection and removal of fiducial projections in fluoroscopy images: an integrated solution.

2011-03-29T07:45:25Z

Automatic detection and removal of fiducial projections in fluoroscopy images is an essential prerequisite for C-arm calibration. This paper presents an integrated solution to fulfill this task. A custom-designed calibration cage with a two-plane pattern of fiducials is utilized in our solution. The cage is attached to the C-arm image intensifier and acquired images are calibrated automatically by...

Guoyan Zheng, Xuan Zhang (2009) Med Eng Phys 31: 5 571-580

Statistically deformable 2D/3D registration for accurate determination of post-operative cup orientation from single standard X-ray radiograph.

2011-03-29T07:45:25Z

The widely used procedure of evaluation of cup orientation following total hip arthroplasty using single standard anteroposterior (AP) radiograph is known inaccurate, largely due to the wide variability in individual pelvic orientation relative to X-ray plate. 2D/3D rigid image registration methods have been introduced for an accurate determination of the post-operative cup alignment with respect ...

Guoyan Zheng (2009) Med Image Comput Comput Assist Interv 12: Pt 1 820-827

Automatic extraction of proximal femur contours from calibrated X-ray images using 3D statistical models: an in vitro study.

2011-03-29T07:45:25Z

Accurate extraction of bone contours from two-dimensional (2D) projective X-ray images is an important component for computer-assisted diagnosis, planning or three-dimensional (3D) reconstruction.

Xiao Dong, Guoyan Zheng (2009) Int J Med Robot 5: 2 213-222

3D reconstruction of a patient-specific surface model of the proximal femur from calibrated x-ray radiographs: a validation study.

2011-03-29T07:45:25Z

Twenty-three femurs (one plastic bone and twenty-two cadaver bones) with both nonpathologic and pathologic cases were considered to validate a statistical shape model based technique for three-dimensional (3D) reconstruction of a patient-specific surface model from calibrated x-ray radiographs. The 3D reconstruction technique is based on an iterative nonrigid registration of the features extracted...

Guoyan Zheng, Steffen Schumann (2009) Med Phys 36: 4 1155-1166

A system for 3-D reconstruction of a patient-specific surface model from calibrated X-ray images.

2011-03-29T07:45:25Z

This paper presents a system for 3-D reconstruction of a patient-specific surface model from calibrated X-ray images. Our system requires two X-ray images of a patient with one acquired from the anterior-posterior direction and the other from the axial direction. A custom-designed cage is utilized in our system to calibrate both images. Starting from bone contours that are interactively identified...

G Zheng, S Schumann (2009) Stud Health Technol Inform 142: 453-458

Validation of a new method for determination of cup orientation in THA.

2011-03-29T07:49:33Z

Our goal was to validate accuracy, consistency, and reproducibility/reliability of a new method for determining cup orientation in total hip arthroplasty (THA). This method allows matching the 3D-model from CT images or slices with the projected pelvis on an anteroposterior pelvic radiograph using a fully automated registration procedure. Cup orientation (inclination and anteversion) is calculated...

Simon D Steppacher, Moritz Tannast, Guoyan Zheng, Xuan Zhang, Jens Kowal, Suzanne E Anderson, Klaus A Siebenrock, Stephen B Murphy (2009) J Orthop Res 27: 12 1583-1588

A novel parameter decomposition based optimization approach for automatic pose estimation of distal locking holes from single calibrated fluoroscopic image

2011-03-29T07:58:30Z

One of the most difficult steps in intramedullary nailing of femoral shaft fractures is distal locking – the insertion of distal transverse interlocking screws, for which it is necessary to know the positions and the orientations of the distal locking holes of the intramedullary nail (IMN). This paper presents a novel parameter decomposition based optimization approach for solving this proble...

G Zheng, X Zhang (2009) Pattern Recognition Letters 30: 838-847

Landmark-based augmented reality system for paranasal and transnasal endoscopic surgeries.

2011-03-29T07:45:25Z

In this paper we present a landmark-based augmented reality (AR) endoscope system for endoscopic paranasal and transnasal surgeries along with fast and automatic calibration and registration procedures for the endoscope.

Ramesh Thoranaghatte, Jaime Garcia, Marco Caversaccio, Daniel Widmer, Miguel A Gonzalez Ballester, Lutz-P Nolte, Guoyan Zheng (2009) Int J Med Robot 5: 4 415-422

Reality-augmented virtual fluoroscopy for computer-assisted diaphyseal long bone fracture osteosynthesis: a novel technique and feasibility study results.

2011-03-29T07:45:25Z

In this paper, a novel technique to create a reality-augmented virtual fluoroscopy for computer-assisted diaphyseal long bone fracture osteosynthesis and feasibility study results are presented. With this novel technique, repositioning of bone fragments during closed fracture reduction and osteosynthesis can lead to image updates in the virtual imaging planes of all acquired images without any rad...

G Zheng, X Dong, P A Gruetzner (2008) Proc Inst Mech Eng H 222: 1 101-115

A robust and accurate two-stage approach for automatic recovery of distal locking holes in computer-assisted intramedullary nailing of femoral shaft fractures.

2011-03-29T07:45:25Z

It has been recognized that one of the most difficult steps in intramedullary nailing of femoral shaft fractures is the distal locking - the insertion of distal transverse interlocking screws, for which it is necessary to know the positions and orientations of the distal locking holes (DLHs) of the intramedullary nail (IMN). This paper presents a robust and accurate approach for solving this probl...

Guoyan Zheng, Xuan Zhang, Daniel Haschtmann, Philippe Gedet, Xiao Dong, Lutz-Peter Nolte (2008) IEEE Trans Med Imaging 27: 2 171-187

[Computer-aided surgery of the paranasal sinuses and the anterior skull base].

2011-03-29T07:44:19Z

Endoscopic or microscopic surgery for chronic rhinosinusitis with or without nasal polyps is a routine intervention in daily practice. It is often a delicate and difficult minimally invasive intervention in a narrow space, with a tunnel view of 4 mm in the case of endoscopy and frequent bleeding in chronically inflamed tissue. Therefore, orientation in such a "labyrinth" is often difficult. In the...

M Caversaccio, G Zheng, L-P Nolte (2008) HNO 56: 4 376-8, 780-2

Effective incorporation of spatial information in a mutual information based 3D-2D registration of a CT volume to X-ray images.

2011-03-29T07:45:25Z

This paper addresses the problem of estimating the 3D rigid pose of a CT volume of an object from its 2D X-ray projections. We use maximization of mutual information, an accurate similarity measure for multi-modal and mono-modal image registration tasks. However, it is known that the standard mutual information measure only takes intensity values into account without considering spatial informatio...

Guoyan Zheng (2008) Med Image Comput Comput Assist Interv 11: Pt 2 922-929

Augmented reality endoscopic system (ARES): preliminary results.

2011-03-29T07:45:25Z

During endoscopic surgery, it is difficult to ascertain the anatomical landmarks once the anatomy is fiddled with or if the operating area is filled with blood. An augmented reality system will enhance the endoscopic view and further enable surgeons to view hidden critical structures or the results of preoperative planning.

Marco Caversaccio, Jaime Garcia Giraldez, Ramesh Thoranaghatte, Guoyan Zheng, Peter Eggli, Lutz-Peter Nolte, Miguel A Gonzalez Ballester (2008) Rhinology 46: 2 156-158

Radiographic analysis of femoroacetabular impingement with Hip2Norm-reliable and validated.

2011-03-29T07:45:25Z

The purpose of this study was to validate the accuracy, consistency, and reproducibility/reliability of a new method for correction of pelvic tilt and rotation of radiographic hip parameters for pincer type of femoroacetabular impingement on an anteroposterior pelvic radiograph. Thirty cadaver hips and 100 randomized, blinded AP pelvic radiographs were used for investigation. To detect the softwar...

Moritz Tannast, Sapan Mistry, Simon D Steppacher, Stephan Reichenbach, Frank Langlotz, Klaus A Siebenrock, Guoyan Zheng (2008) J Orthop Res 26: 9 1199-1205

Calibration of a surgical microscope with automated zoom lenses using an active optical tracker.

2011-03-29T07:45:25Z

In this paper, we present a new method for the calibration of a microscope and its registration using an active optical tracker.

Jaime García, Ramesh Thoranaghatte, Gaetan Marti, Guoyan Zheng, Marco Caversaccio, Miguel A González Ballester (2008) Int J Med Robot 4: 1 87-93

Comparison of computer assisted surgery with conventional technique for treatment of abaxial distal phalanx fractures in horses: an in vitro study.

2011-03-29T07:45:25Z

To (1) evaluate and compare computer-assisted surgery (CAS) with conventional screw insertion (conventional osteosynthesis [COS]) for treatment of equine abaxial distal phalanx fractures; (2) compare planned screw position with actual postoperative position; and (3) determine preferred screw insertion direction.

Melanie Rossol, Diego Gygax, Juliane Andritzky-Waas, Guoyan Zheng, Christoph J Lischer, Xuan Zhang, Joerg A Auer (2008) Vet Surg 37: 1 32-42

Accurate and robust reconstruction of a surface model of the proximal femur from sparse-point data and a dense-point distribution model for surgical navigation.

2011-03-29T07:45:25Z

Constructing a 3-D surface model from sparse-point data is a nontrivial task. Here, we report an accurate and robust approach for reconstructing a surface model of the proximal femur from sparse-point data and a dense-point distribution model (DPDM). The problem is formulated as a three-stage optimal estimation process. The first stage, affine registration, is to iteratively estimate a scale and a...

Guoyan Zheng, Xiao Dong, Kumar T Rajamani, Xuan Zhang, Martin Styner, Ramesh U Thoranaghatte, Lutz-Peter Nolte, Miguel A González Ballester (2007) IEEE Trans Biomed Eng 54: 12 2109-2122

A CT-free, intra-operative planning and navigation system for minimally invasive anterior spinal surgery - an accuracy study.

2011-03-29T08:01:13Z

A comprehensive study was performed to evaluate the accuracy of a newly developed CT-free, intra-operative planning and navigation system for anterior spine surgery.

B Maier, G Zheng, C Ploss, X Zhang, K Welle, L-P Nolte, I Marzi (2007) Comput Aided Surg 12: 4 233-241

Statistical deformable bone models for robust 3D surface extrapolation from sparse data.

2011-03-29T07:45:25Z

A majority of pre-operative planning and navigational guidance during computer assisted orthopaedic surgery routinely uses three-dimensional models of patient anatomy. These models enhance the surgeon's capability to decrease the invasiveness of surgical procedures and increase their accuracy and safety. A common approach for this is to use computed tomography (CT) or magnetic resonance imaging (M...

Kumar T Rajamani, Martin A Styner, Haydar Talib, Guoyan Zheng, Lutz P Nolte, Miguel A González Ballester (2007) Med Image Anal 11: 2 99-109

Automated detection and segmentation of cylindrical fragments from calibrated C-arm images for long bone fracture reduction.

2011-03-29T07:45:25Z

Long bone fracture belongs to one of the most common injuries encountered in clinical routine trauma surgery. Automated identification, pose and size estimation, and contour extraction of diaphyseal bone fragments can greatly improve the usability of a computer-assisted, fluoroscopy-based navigation system for long bone fracture reduction. In this paper, a two-step solution is proposed. In the fir...

Guoyan Zheng, Xiao Dong, Paul Alfred Grutzner, Lutz-Peter Nolte (2007) Comput Methods Programs Biomed 87: 1 1-11

Precise estimation of postoperative cup alignment from single standard X-ray radiograph with gonadal shielding.

2011-03-29T07:45:25Z

This paper addresses the problem of estimating postoperative cup alignment from single standard X-ray radiograph with gonadal shielding. The widely used procedure of evaluation of cup orientation following total hip arthroplasty using single standard anteroposterior radiograph is known inaccurate, largely due to the wide variability in individual pelvic position relative to X-ray plate. 2D-3D imag...

Guoyan Zheng, Simon Steppacher, Xuan Zhang, Moritz Tannast (2007) Med Image Comput Comput Assist Interv 10: Pt 2 951-959

Unsupervised reconstruction of a patient-specific surface model of a proximal femur from calibrated fluoroscopic images.

2011-03-29T07:45:25Z

In this paper, we present an unsupervised 2D/3D reconstruction scheme combining a parameterized multiple-component geometrical model and a point distribution model, and show its application to automatically reconstruct a surface model of a proximal femur from a limited number of calibrated fluoroscopic images with no user intervention at all. The parameterized multiple-component geometrical model ...

Guoyan Zheng, Xiao Dong, Miguel A Gonzalez Ballester (2007) Med Image Comput Comput Assist Interv 10: Pt 1 834-841

Accurate and reliable pose recovery of distal locking holes in computer-assisted intra-medullary nailing of femoral shaft fractures: a preliminary study.

2011-03-29T07:45:25Z

One of the difficult steps in intra-medullary nailing of femoral shaft fractures is distal locking - the insertion of distal interlocking screws. Conventionally, this is performed using repeated image acquisitions, which leads to considerable irradiation of the patient and surgical team. Virtual fluoroscopy has been used to reduce radiation exposure, but can only provide multi-planar two-dimension...

Guoyan Zheng, Xuan Zhang, Daniel Haschtmann, Philippe Gédet, Frank Langlotz, Lutz P Nolte (2007) Comput Aided Surg 12: 3 138-151

Hip2Norm: an object-oriented cross-platform program for 3D analysis of hip joint morphology using 2D pelvic radiographs.

2011-03-29T07:45:25Z

We developed an object-oriented cross-platform program to perform three-dimensional (3D) analysis of hip joint morphology using two-dimensional (2D) anteroposterior (AP) pelvic radiographs. Landmarks extracted from 2D AP pelvic radiographs and optionally an additional lateral pelvic X-ray were combined with a cone beam projection model to reconstruct 3D hip joints. Since individual pelvic orientat...

G Zheng, M Tannast, C Anderegg, K A Siebenrock, F Langlotz (2007) Comput Methods Programs Biomed 87: 1 36-45

Navigated open-wedge high tibial osteotomy: advantages and disadvantages compared to the conventional technique in a cadaver study.

2011-03-29T07:59:37Z

High tibial osteotomy (HTO) is an established therapy for the treatment of symptomatic varus malaligned knees. A main reason for disappointing clinical results after HTO is the under- and overcorrection of the mechanical axis due to insufficient intraoperative visualisation. Twenty legs of fresh human cadaver were randomly assigned to navigated open-wedge HTO (n=10) or conventional HTO using the c...

S Hankemeier, T Hufner, G Wang, D Kendoff, J Zeichen, G Zheng, C Krettek (2006) Knee Surg Sports Traumatol Arthrosc 14: 10 917-921

Zero-dose fluoroscopy-based close reduction and osteosynthesis of diaphyseal fracture of femurs.

2011-03-29T07:45:25Z

This paper presents a novel technique to create a computerized fluoroscopy with zero-dose image updates for computer-assisted fluoroscopy-based close reduction and osteosynthesis of diaphyseal fracture of femurs. With the novel technique, repositioning of bone fragments during close fracture reduction will lead to image updates in each acquired imaging plane, which is equivalent to using several f...

Guoyan Zheng, Xiao Dong, Frank Langlotz, Paul Alfred Gruetzner (2006) Stud Health Technol Inform 119: 592-594

Assessment of spline-based 2D-3D registration for image-guided spine surgery.

2011-03-29T07:45:25Z

2D-3D registration of pre-operative 3D volumetric data with a series of calibrated and undistorted intra-operative 2D projection images has shown great potential in CT-based surgical navigation because it obviates the invasive procedure of the conventional registration methods. In this study, a recently introduced spline-based multi-resolution 2D-3D image registration algorithm has been adapted to...

Xuan Zhang, Guoyan Zheng, Frank Langlotz, Lutz-Peter Nolte (2006) Minim Invasive Ther Allied Technol 15: 3 193-199

Reconstruction of patient-specific 3D bone surface from 2D calibrated fluoroscopic images and point distribution model.

2011-03-29T07:45:25Z

Reconstruction of patient-specific 3D bone surface from 2D calibrated fluoroscopic images and a point distribution model is discussed. We present a 2D/3D reconstruction scheme combining statistical extrapolation and regularized shape deformation with an iterative image-to-model correspondence establishing algorithm, and show its application to reconstruct the surface of proximal femur. The image-t...

Guoyan Zheng, Miguel A G Ballester, Martin Styner, Lutz-Peter Nolte (2006) Med Image Comput Comput Assist Interv 9: Pt 1 25-32

Computer-assisted, fluoroscopy-based ventral spondylodesis of thoracolumbar fractures.

2011-03-29T07:45:25Z

To design and evaluate a novel computer-assisted, fluoroscopy-based planning and navigation system for minimally invasive ventral spondylodesis of thoracolumbar fractures.

G Zheng, B Maier, C Ploss, I Marzi, L-P Nolte (2006) Technol Health Care 14: 2 109-122

Implementation, accuracy evaluation, and preliminary clinical trial of a CT-free navigation system for high tibial opening wedge osteotomy.

2011-03-29T07:45:25Z

The objectives of this study are to design and evaluate a CT-free intra-operative planning and navigation system for high tibial opening wedge osteotomy. This is a widely accepted treatment for medial compartment osteoarthritis and other lower extremity deformities, particularly in young and active patients for whom total knee replacement is not advised. However, it is a technically demanding proc...

Gongli Wang, Guoyan Zheng, Peter Keppler, Florian Gebhard, Alex Staubli, Urs Mueller, Daniel Schmucki, Simon Fluetsch, Lutz-Peter Nolte (2005) Comput Aided Surg 10: 2 73-85

Tilt and rotation correction of acetabular version on pelvic radiographs.

2011-03-29T07:45:25Z

Anteroposterior pelvic radiographs are the gold standard of imaging for mechanical hip problems. However, correct interpretation is difficult because the projected morphologic features of the acetabulum and nearly all routinely used hip parameters depend on individual pelvic position, which can vary considerably during acquisition. We developed software that recreates the projected acetabular rim ...

M Tannast, G Zheng, C Anderegg, K Burckhardt, F Langlotz, R Ganz, K A Siebenrock (2005) Clin Orthop Relat Res 438: 182-190

Navigated intraoperative analysis of lower limb alignment.

2011-03-29T08:00:04Z

Accurate intraoperative assessment of lower limb alignment is crucial for the treatment of long bone fractures, implantation of knee arthroplasties and correction of deformities. During orthopaedic surgery, exact real time control of the mechanical axis is strongly desirable. The aim of this study was to compare conventional intraoperative analysis of the mechanical axis by the cable method with c...

Stefan Hankemeier, Tobias Hufner, Gongli Wang, Daniel Kendoff, Guoyan Zheng, Martinus Richter, Thomas Gosling, Lutz Nolte, Christian Krettek (2005) Arch Orthop Trauma Surg 125: 8 531-535

A fluoroscopy-based surgical navigation system for high tibial osteotomy.

2011-03-29T07:45:25Z

High tibial osteotomy is a widely accepted treatment for unicompartmental osteoarthritis of the knee and other lower extremity deformities, particularly in young and active patients. However, it is generally recognized as a technically demanding procedure. The lack of intraoperative control of the mechanical axis of the affected limb often results in postoperative malalignments, which is one of th...

Gongli Wang, Guoyan Zheng, Paul Alfred Gruetzner, Urs Mueller-Alsbach, Jan von Recum, Alex Staubli, Lutz-Peter Nolte (2005) Technol Health Care 13: 6 469-483

New orthopaedic implant management tool for computer-assisted planning, navigation, and simulation: from implant CAD files to a standardized XML-based implant database.

2011-03-29T07:45:25Z

Computer-Assisted Orthopaedic Surgery (CAOS) has made much progress over the last 10 years. Navigation systems have been recognized as important tools that help surgeons, and various such systems have been developed. A disadvantage of these systems is that they use non-standard formalisms and techniques. As a result, there are no standard concepts for implant and tool management or data formats to...

S Sagbo, F Blochaou, F Langlotz, C Vangenot, L-P Nolte, G Zheng (2005) Comput Aided Surg 10: 5-6 311-319

Computer-assisted LISS plate osteosynthesis of proximal tibia fractures: feasibility study and first clinical results.

2011-03-29T07:51:27Z

Fluoroscopy is the most common tool for the intraoperative control of long-bone fracture reduction. Limitations of this technology include high radiation exposure for the patient and the surgical team, limited visual field, distorted images, and cumbersome verification of image updating. Fluoroscopy-based navigation systems partially address these limitations by allowing fluoroscopic images to be ...

Paul Alfred Grützner, Frank Langlotz, Guoyan Zheng, Jan von Recum, Christina Keil, Lutz P Nolte, Andreas Wentzensen, Klaus Wendl (2005) Comput Aided Surg 10: 3 141-149

Endoscope-based hybrid navigation system for minimally invasive ventral spine surgeries.

2011-03-29T07:45:25Z

The availability of high-resolution, magnified, and relatively noise-free endoscopic images in a small workspace, 4-10 cm from the endoscope tip, opens up the possibility of using the endoscope as a tracking tool. We are developing a hybrid navigation system in which image-analysis-based 2D-3D tracking is combined with optoelectronic tracking (Optotrak) for computer-assisted navigation in laparosc...

Ramesh U Thoranaghatte, Guoyan Zheng, Frank Langlotz, Lutz-Peter Nolte (2005) Comput Aided Surg 10: 5-6 351-356

Computer aided reduction and imaging.

2011-03-29T07:45:25Z

Reduction is one of the key procedures in orthopedic trauma surgery and has been acknowledged as one of the conditions for a good outcome in intraarticular and extra-articular fractures. The information available to the surgeon during the reduction maneuver can be divided into visual and tactile information. The optimal implementation of these parameters, combined with the surgeon's individual exp...

Daniel Schmucki, Florian Gebhard, Paul A Grützner, Tobias Hüfner, Frank Langlotz, Guoyan Zheng (2004) Injury 35 Suppl 1: S-A96-104

Computer aided high tibial open wedge osteotomy.

2011-03-29T07:51:27Z

High tibial osteotomy is a widely accepted treatment of medial compartment osteoarthritis as well as other lower extremity deformities. However, it is a technically demanding procedure. The lack of exact intraoperative real time control of the mechanical axis often results in postoperative malalignments, which is one reason for poor long term results. These problems can be addressed with the use o...

Peter Keppler, Florian Gebhard, Paul A Grützner, Gongli Wang, Guoyan Zheng, Tobias Hüfner, Stefan Hankemeier, Lutz-Peter Nolte (2004) Injury 35 Suppl 1: S-A68-78

C-arm based navigation in total hip arthroplasty-background and clinical experience.

2011-03-29T07:51:27Z

After experimental and preclinical evaluation of a CT-free image guided surgical navigation system for acetabular cup placement, the system was introduced into clinical routine. The computation of the angular orientation of the cup is based on reference coordinates from the anterior pelvic plane concept. A hybrid strategy for pelvic landmark acquisition has been introduced, involving percutaneous ...

Paul A Grützner, Guoyan Zheng, Ulrich Langlotz, Jan von Recum, Lutz P Nolte, Andreas Wentzensen, Karl-Heinz Widmer, Klaus Wendl (2004) Injury 35 Suppl 1: S-A90-5

Image-based hip navigation.

2011-03-29T07:51:27Z

After experimental and preclinical evaluation (HAP Paul Award 2001) of a CT-free image-guided surgical navigation system for acetabular cup placement, the system was introduced into clinical routine. The computation of the angular orientation of the cup is based on reference coordinates from the anterior pelvic plane (APP) concept. A hybrid strategy for pelvic landmark acquisition has been introdu...

Andreas Wentzensen, Guoyan Zheng, Bernd Vock, Ulrich Langlotz, Jürgen Korber, Lutz P Nolte, Paul A Grützner (2003) Int Orthop 27 Suppl 1: S43-S46

A hybrid CT-free navigation system for total hip arthroplasty.

2011-03-29T07:45:25Z

To design and evaluate a novel CT-free image-guided surgical navigation system for assisting placement of both acetabular and femoral components in total hip arthroplasty (THA).

Guoyan Zheng, Axel Marx, Ulrich Langlotz, Karl-Heinz Widmer, Martin Buttaro, Lutz-Peter Nolte (2002) Comput Aided Surg 7: 3 129-145

Frameless optical computer-aided tracking of a microscope for otorhinology and skull base surgery.

2011-03-29T07:45:25Z

To integrate a digitally controlled operating microscope without a laser autofocus system into a frameless optical computer-aided surgery system and to test the accuracy and usability of this system in otorhinological surgery.

G Zheng, M Caversaccio, R Bächler, F Langlotz, L P Nolte, R Häusler (2001) Arch Otolaryngol Head Neck Surg 127: 10 1233-1238