International Journal of Computer Assisted Radiology and Surgery

http://link.springer.com/journal/11548

List of Papers (Total 158)

Context aware decision support in neurosurgical oncology based on an efficient classification of endomicroscopic data

PurposeProbe-based confocal laser endomicroscopy (pCLE) enables in vivo, in situ tissue characterisation without changes in the surgical setting and simplifies the oncological surgical workflow. The potential of this technique in identifying residual cancer tissue and improving resection rates of brain tumours has been recently verified in pilot studies. The interpretation of...

Analytical derivation of elasticity in breast phantoms for deformation tracking

PurposePatient-specific biomedical modeling of the breast is of interest for medical applications such as image registration, image guided procedures and the alignment for biopsy or surgery purposes. The computation of elastic properties is essential to simulate deformations in a realistic way. This study presents an innovative analytical method to compute the elastic modulus and...

A pre-operative planning framework for global registration of laparoscopic ultrasound to CT images

PurposeLaparoscopic ultrasound (LUS) enhances the safety of laparoscopic liver resection by enabling real-time imaging of internal structures such as vessels. However, LUS probes can be difficult to use, and many tumours are iso-echoic and hence are not visible. Registration of LUS to a pre-operative CT or MR scan has been proposed as a method of image guidance. However, the...

Robust and semantic needle detection in 3D ultrasound using orthogonal-plane convolutional neural networks

PurposeDuring needle interventions, successful automated detection of the needle immediately after insertion is necessary to allow the physician identify and correct any misalignment of the needle and the target at early stages, which reduces needle passes and improves health outcomes.MethodsWe present a novel approach to localize partially inserted needles in 3D ultrasound...

3D/2D model-to-image registration by imitation learning for cardiac procedures

PurposeIn cardiac interventions, such as cardiac resynchronization therapy (CRT), image guidance can be enhanced by involving preoperative models. Multimodality 3D/2D registration for image guidance, however, remains a significant research challenge for fundamentally different image data, i.e., MR to X-ray. Registration methods must account for differences in intensity, contrast...

In vivo estimation of target registration errors during augmented reality laparoscopic surgery

PurposeSuccessful use of augmented reality for laparoscopic surgery requires that the surgeon has a thorough understanding of the likely accuracy of any overlay. Whilst the accuracy of such systems can be estimated in the laboratory, it is difficult to extend such methods to the in vivo clinical setting. Herein we describe a novel method that enables the surgeon to estimate in...

Can tumor coverage evaluated 24 h post-radiofrequency ablation predict local tumor progression of liver metastases?

PurposeTo assess the predictive value for local tumor progression (LTP) of geometrical tumor coverage using the contrast-enhanced (ce-)CT images acquired before and within 24 h after radiofrequency (RF) ablation.MethodsTwenty patients (6 male and 14 female, median age 62 years) with 45 focal hypovascular liver metastases (16 colorectal carcinoma, 3 melanoma and 1 breast carcinoma...

Real-time inextensible surgical thread simulation

PurposeThis paper discusses a real-time simulation method of inextensible surgical thread based on the Cosserat rod theory using position-based dynamics (PBD). The method realizes stable twining and knotting of surgical thread while including inextensibility, bending, twisting and coupling effects.MethodsThe Cosserat rod theory is used to model the nonlinear elastic behavior of...

A hybrid optimization strategy for registering images with large local deformations and intensity variations

PurposeTo develop a method for intra-patient registration of pre- and post-contrast abdominal MR images with large local deformations and large intensity variations.MethodA hybrid method is proposed to deal with this problem. It consists of two coupled techniques: (1) descriptor matching (DM) at the original resolution using a discrete optimization strategy to avoid getting...

Positioning error of custom 3D-printed surgical guides for the radius: influence of fitting location and guide design

PurposeUtilization of 3D-printed patient-specific surgical guides is a promising navigation approach for orthopedic surgery. However, navigation errors can arise if the guide is not correctly positioned at the planned bone location, compromising the surgical outcome. Quantitative measurements of guide positioning errors are rarely reported and have never been related to guide...

VCSim3: a VR simulator for cardiovascular interventions

Purpose Effective and safe performance of cardiovascular interventions requires excellent catheter/guidewire manipulation skills. These skills are currently mainly gained through an apprenticeship on real patients, which may not be safe or cost-effective. Computer simulation offers an alternative for core skills training. However, replicating the physical behaviour of real...

Anthropomorphic liver phantom with flow for multimodal image-guided liver therapy research and training

Purpose The objective of this study was to develop a multimodal, permanent liver phantom displaying functional vasculature and common pathologies, for teaching, training and equipment development in laparoscopic ultrasound and navigation. Methods Molten wax was injected simultaneously into the portal and hepatic veins of a human liver. Upon solidification of the wax, the...

Simulation of facial expressions using person-specific sEMG signals controlling a biomechanical face model

Purpose Functional inoperability in advanced oral cancer is difficult to assess preoperatively. To assess functions of lips and tongue, biomechanical models are required. Apart from adjusting generic models to individual anatomy, muscle activation patterns (MAPs) driving patient-specific functional movements are necessary to predict remaining functional outcome. We aim to...

Contour segmentation of the intima, media, and adventitia layers in intracoronary OCT images: application to fully automatic detection of healthy wall regions

Purpose Quantitative and automatic analysis of intracoronary optical coherence tomography images is useful and time-saving to assess cardiovascular risk in the clinical arena. Methods First, the interfaces of the intima, media, and adventitia layers are segmented, by means of an original front propagation scheme, running in a 4D multi-parametric space, to simultaneously extract...

Experimental validation of predicted application accuracies for computer-assisted (CAS) intraoperative navigation with paired-point registration

Purpose The target registration error (TRE) is a crucial parameter to estimate the potential usefulness of computer-assisted navigation intraoperatively. Both image-to-patient registration on base of rigid-body registration and TRE prediction methods are available for spatially isotropic and anisotropic data. This study presents a thorough validation of data obtained in an...

Using needle orientation sensing as surrogate signal for respiratory motion estimation in percutaneous interventions

Purpose To develop and evaluate an approach to estimate the respiratory-induced motion of lesions in the chest and abdomen. Materials and methods The proposed approach uses the motion of an initial reference needle inserted into a moving organ to estimate the lesion (target) displacement that is caused by respiration. The needles position is measured using an inertial measurement...