Evaluation of state-of-the-art segmentation algorithms for left ventricle infarct from late Gadolinium enhancement MR images.

Studies have demonstrated the feasibility of late Gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging for guiding the management of patients with sequelae to myocardial infarction, such as ventricular tachycardia and heart failure. Clinical implementation of these developments necessitates a reproducible and reliable segmentation of the infarcted regions. It is challenging to compare new algorithms for infarct segmentation in the left ventricle (LV) with existing algorithms.

Risk of venous congestion in live donors of extended right liver graft.

Aim: To investigate middle hepatic vein (MHV) management in adult living donor liver transplantation and safer remnant volumes (RV).

Methods: There were 59 grafts with and 12 grafts without MHV (including 4 with MHV-5/8 reconstructions). All donors underwent our five-step protocol evaluation containing a preoperative protocol liver biopsy Congestive vs non-congestive RV, remnant-volume-body-weight ratios (RVBWR) and postoperative outcomes were evaluated in 71 right graft living donors.

Comparison of volumetric and linear serial CT assessments of lung metastases in renal cell carcinoma patients in a clinical phase IIB study.

Rationale And Objectives: Accuracy of radiologic assessment may have a crucial impact on clinical studies and therapeutic decisions. We compared the variability of a central radiologic assessment (RECIST) and computer-aided volume-based assessment of lung lesions in patients with metastatic renal cell carcinoma (RCC).

Materials And Methods: The investigation was prospectively planned as a substudy of a clinical randomized phase IIB therapeutic trial in patients with RCC.

Evaluation of current algorithms for segmentation of scar tissue from late gadolinium enhancement cardiovascular magnetic resonance of the left atrium: an open-access grand challenge.

Background: Late Gadolinium enhancement (LGE) cardiovascular magnetic resonance (CMR) imaging can be used to visualise regions of fibrosis and scarring in the left atrium (LA) myocardium. This can be important for treatment stratification of patients with atrial fibrillation (AF) and for assessment of treatment after radio frequency catheter ablation (RFCA). In this paper we present a standardised evaluation benchmarking framework for algorithms segmenting fibrosis and scar from LGE CMR images.

Computer-assisted surgical planning in adult-to-adult live donor liver transplantation: how much does it help? A single center experience.

Background: Preoperative imaging and donor selection are cardinal components of adult-to-adult live donor liver transplantation (ALDLT). The purpose of this study was to evaluate our three-dimensional (3D) computed tomography image-derived computer-assisted surgical planning (3D CASP) in ALDLT.

Methods: Eighty-three consecutive ALDLTs (71 right and 12 left) were planned with 3D CASP.

The "carving" liver partitioning technique for graft hepatectomy in live donor liver transplantation: a single-center experience.

Background: In adult live donor liver transplantation, postoperative venous congestion of graft and remnant livers can lead to life-threatening complications. The purpose of this study was to evaluate the safety and benefits of our 3-dimensional, computed tomographic, computer-assisted donor hepatectomy using the "carving" partitioning technique.

Methods: Eighty-three consecutive adult live donor liver transplantations were performed based on data obtained from individualized preoperative 3-dimensional, computed tomographic reconstructions and virtual graft hepatectomies.

Workflow-centred evaluation of an automatic lesion tracking software for chemotherapy monitoring by CT.

Objectives: In chemotherapy monitoring, an estimation of the change in tumour size is an important criterion for the assessment of treatment success. This requires a comparison between corresponding lesions in the baseline and follow-up computed tomography (CT) examinations. We evaluate the clinical benefits of an automatic lesion tracking tool that identifies the target lesions in the follow-up CT study and pre-computes the lesion volumes.

Precise local resection for hepatocellular carcinoma based on tumor-surrounding vascular anatomy revealed by 3D analysis.

Purposes: Local resection for hepatocellular carcinoma (HCC) has been traditionally performed non-anatomically. The purpose of this study is to evaluate the feasibility of precise local resection of HCC according to the anatomy of tumor-surrounding vessels revealed by three-dimensional (3D) analysis technique.

Methods: The CT datasets of the livers of the patients with HCC were analyzed three-dimensionally.

Image-guided therapies.

This paper presents image-guided therapies development and advantages using real time imaging modalities such as computed tomography, ultrasound imaging, and magnetic resonance imaging. The following are also highlighted: image-guided cancer interventions and image-guided cardiovascular interventions.

Probabilistic 4D blood flow tracking and uncertainty estimation.

Phase-Contrast (PC) MRI utilizes signal phase shifts resulting from moving spins to measure tissue motion and blood flow. Time-resolved 4D vector fields representing the motion or flow can be derived from the acquired PC MRI images. In cardiovascular PC MRI applications, visualization techniques such as vector glyphs, streamlines, and particle traces are commonly employed for depicting the blood flow.

Visualization support for the planning of hepatic needle placement.

Purpose: Percutaneous image-guided interventions, such as radiofrequency ablation or biopsy, are using needle-shaped instruments which have to be inserted into a target area without penetrating any vital structure. The established planning workflow is based on viewing 2D slices of a pre-interventional CT or MR scan. However, access paths not parallel to the axial plane are often necessary.

Object-based analysis of CT images for automatic detection and segmentation of hypodense liver lesions.

Purpose: Hypodense liver lesions are commonly detected in CT, so their segmentation and characterization are essential for diagnosis and treatment. Methods for automatic detection and segmentation of liver lesions were developed to support this task.

Methods: The detection algorithm uses an object-based image analysis approach, allowing for effectively integrating domain knowledge and reasoning processes into the detection logic.

A robust and extendible framework for medical image registration focused on rapid clinical application deployment.

Development and integration of image registration methods become increasingly important for clinical workstations. Due to the complexity of such methods, prototyping, evaluation and workflow integration require in-depth knowledge foremostly available to registration developers. Rapid development and deployment is therefore often difficult, particularly for comprehensive software frameworks.

In vivo validation of a therapy planning system for laser-induced thermotherapy (LITT) of liver malignancies.

Purpose: In situ ablation is increasingly being used for the treatment of liver malignancies. The application of these techniques is limited by the lack of a precise prediction of the destruction volume. This holds especially true in anatomically difficult situations, such as metastases in the vicinity of larger liver vessels.

Fusion of MR coronary angiography and viability imaging: feasibility and clinical value for the assignment of myocardial infarctions.

Purpose: To investigate the feasibility of image fusion of MR-coronary angiography (MRCA) and delayed gadolinium enhancement imaging (LGE) and to assign areas of myocardial infarction to the corresponding supplying coronary arteries.

Materials And Methods: An interactive segmentation of the coronary arteries was performed in MRCA data sets (n=25). The LGE slices were matched onto the vessel segmentation to perform a fused analysis of coronary artery anatomy and LGE.

Probabilistic 4D blood flow mapping.

Blood flow and tissue velocity can be measured using phase-contrast MRI. In this work, the statistical properties of 4D phase-contrast images are derived, and a novel probabilistic blood flow mapping method based on sequential Monte Carlo sampling is presented. The resulting flow maps visualize and quantify the uncertainty in conventional flow visualization techniques such as streamlines and particle traces.

Assessment of intraoperative liver deformation during hepatic resection: prospective clinical study.

Background: The implementation of intraoperative navigation in liver surgery is handicapped by intraoperative organ shift, tissue deformation, the absence of external landmarks, and anatomical differences in the vascular tree. To investigate the impact of surgical manipulation on the liver surface and intrahepatic structures, we conducted a prospective clinical trial.

Methods: Eleven consecutive patients [4 female and 7 male, median age = 67 years (range = 54-80)] with malignant liver disease [colorectal metastasis (n = 9) and hepatocellular cancer (n = 2)] underwent hepatic resection.

Liver segments: an anatomical rationale for explaining inconsistencies with Couinaud's eight-segment concept.

Background And Purpose: An increasing number of surgical and radiological observations call Couinaud's concept of eight liver segments into question and such inconsistencies are commonly explained with anatomical variations. This paper was intended to demonstrate that, beyond variability, another anatomical principle may allow to understand supposedly differing concepts on liver segmentation.

Materials And Methods: The study was performed on 25 portal vein casts scanned by helical CT.

Multiple hypothesis template tracking of small 3D vessel structures.

A multiple hypothesis tracking approach to the segmentation of small 3D vessel structures is presented. By simultaneously tracking multiple hypothetical vessel trajectories, low contrast passages can be traversed, leading to an improved tracking performance in areas of low contrast. This work also contributes a novel mathematical vessel template model, with which an accurate vessel centerline extraction is obtained.

Interactive determination of robust safety margins for oncologic liver surgery.

Objective: Complex oncologic interventions in the liver require an extensive and careful preoperative analysis. Particularly the achievement of an optimal safety margin around tumors remains a difficult task for surgeons.

Methods: We present new methods for evaluating different safety margins and their effect on the associated interruption of vascular supply or drainage.

Illustrative visualization of 3D planning models for augmented reality in liver surgery.

Purpose: Augmented reality (AR) obtains increasing acceptance in the operating room. However, a meaningful augmentation of the surgical view with a 3D visualization of planning data which allows reliable comparisons of distances and spatial relations is still an open request.

Methods: We introduce methods for intraoperative visualization of 3D planning models which extend illustrative rendering and AR techniques.