Imaging decisions (Berlin, Germany)最新文献

The increasing complexity of hepato-biliary surgery, including major hepatic resections and living donor liver transplantation (LDLT), has lead to an increasing demand for sophisticated imaging modalities. Standard operation planning for hepatic resections and preoperative donor and recipient work-up for LDLT is based on two-dimensional computed tomography (CT) images and magnetic resonance imaging. However, even modern multidetector CT scanners are not able to perform routinely three-dimensional (3D) visualization needed for operation planning in liver surgery or LDLT. As a consequence, special-purpose computer-based operation planning systems have been developed that leverage the possibilities of modern image processing to improve surgical planning. The advances in technology enable surgeons to analyse and to visualize the anatomy of the human liver including the vascular structures within the human liver and define the exact volumetric data of the liver tissue to be resected or preserved. Furthermore, 3D visualization of the vessel architecture within the human liver allows a reliable estimation of the amount of liver tissue that could be at risk after resection because of inadequate hepatovenous drainage. Because of its clinical usefulness and real-time visualization capabilities we already use an operation planning system in selected patients prior to liver resection and before donor hepatectomy for LDLT as a standard.

During the last few years, modern cross-sectional imaging techniques have pioneered forensic medicine. Magnetic resonance imaging and especially multislice computed tomography are becoming increasingly implemented into post-mortem examinations. These non-invasive techniques can augment and even partially replace a traditional autopsy. Beside the radiological imaging techniques, the methods of three-dimensional surface scanning and photogrammetry are used for the documentation of the external findings of the body. To realize the goal of a minimal-invasive autopsy, other tools like post-mortem biopsy and post-mortem angiography have been developed. In analogy to the clinical use of biopsy and angiography these techniques will permit post-mortem tissue sampling for further analyses and enable post-mortem examinations of the vascular system. With the use of these methods, a minimally invasive, objective and investigator-independent documentation of forensic cases can be realized to reach quality improvements in forensic pathological investigations.

Virtual bronchoscopy is evolving rapidly, and is becoming accepted into standard clinical practice. Virtual bronchoscopy is a term, which encompasses not only multi-row detector X-ray computerized tomography-derived images, but also other computer graphics and computer vision-derived value-added digital imagery. Other imaging data sources used to create three-dimensional image renderings of the bronchial tree include magnetic resonance imaging, positron emission tomography, the digital colour image taken at real bronchoscopy as part of macro-optical imaging, and various emerging micro-optical imaging modalities, such as catheter-based confocal microscopy and optical coherence tomography. Software solutions now exist for providing simple renderings of the bronchial tree through which a fly-through of the airway lumen along the centreline of the airway can be added (the fly-through mimics the view that a real flexible bronchoscope affords the operator). The images so produced are visually accurate and with currently available software also analytically correct. More advanced virtual bronchoscopic applications, including image-based pathfinding to mediastinal and peripheral lung structures, are also in development, and are finding their way into clinical studies. Exciting and synergistic data sets composed of image data from multiple image sources are also being constructed. One emerging issue is to enhance the understanding and reporting on these data sets, which are often complex, and which are full of useful as well as redundant information. The new discipline of eidomics will inform the non-specialist end user, and act to predict important outcomes. These increasingly powerful tools will continue to advance the use of imaging in technology-supported personalized medicine, to compliment the information from genomics.

In craniofacial surgery it is not easy to predict the shape of the postoperative face, as muscular changes resulting from the surgery cannot be found by a simple way. Three-dimensional (3D) computer simulation of craniofacial surgery can be extremely useful to foresee the surgical outcome. Many authors proposed computer systems for craniofacial surgical planning based on computed tomographic (CT) images. A number of methods to achieve the prediction of soft tissue behaviour have been proposed from computer-aided surgical planning system integrating anatomy-based 3D finite element tissue model to methods for computation of soft-tissue deformation in craniofacial surgery directly from CT images without any intermediate geometric model. We present a review of present techniques on the use of imaging in the presurgical planning of facial surgery and reconstruction. The entire workflow of image acquisition, tissue segmentation, tissue classification, surgical planning, soft tissue displacement computer simulation and visualization is outlined and different cases of real maxillofacial surgery are illustrated.

Virtual colonoscopy (VC) is an emerging technique for colorectal polyp detection in a normal-risk screening population, in patients who have undergone incomplete colonoscopy, or patients who cannot undergo optical colonoscopy. Improvements in technology since VC's description over a decade ago have improved sensitivity for polyp detection. The current recommendations for VC technique include cathartic bowel preparation and faecal tagging, scanning with multi-detector computed tomography scanner, 2D and 3D interpretation on a dedicated viewing platform, a standardized system for reporting VC results [CT Colonography Reporting and Data System (C-RADS)], and suggesting appropriate follow-up. Given the significant learning curve for performing and interpreting VC, if this technique is to gain credibility, those who perform VC must be well-trained and must understand the limitations of VC for detection of small lesions and extra-colonic pathology. Institutional implementation of VC can be challenging. Using this less-invasive technique to increase patient compliance with colorectal polyp screening (and ultimately the incidence and mortality of colorectal cancer) is the goal.

This paper describes the modern imaging methods, techniques, ability and performance in detecting and staging head and neck lymph nodes. Furthermore, the imaging morphologies of benign and malignant lymph nodes according to the different imaging techniques are shown. The imaging techniques of ultrasonography, computed tomography and magnetic resonance imaging (MRI) including diffusion-weighted imaging and contrast-enhanced iron oxide MRI are explained. Imaging examples of the different modalities of benign- and malignant-transformed lymph nodes are shown. Additionally, the diagnostic sensitivity of each modality are delineated and further aspects of modern lymph node staging of the head and neck region, such as those with special contrast agents are described. These modern imaging modalities have sensitivity rates of 70–80% depending on the technical equipment and ability and on the experience of the investigator. The value of biopsy techniques including recently developed ultrasonography guided needle biopsy with molecular analysis of the cells of about 97–100% accuracy in diagnosing benign from malignant lymph nodes are mentioned. Overall, the reader gets an overview of the present imaging modalities to potentially stage correctly lymph nodes in the head and neck region to facilitate the therapeutic procedure.

Treatment and prognosis of malignant lymphomas depend on accurate staging and evaluation of clinical and histological features. Computed tomography (CT), magnetic resonance imaging and ultrasound are standard conventional imaging procedures for staging and, under certain circumstances, are supplemented by skeletal scintigraphy, biopsy from suspected areas of organ involvement and bone marrow biopsy. The determination of response to therapy, which is still the most important marker of prognosis [J Clin Oncol17 (1999) 1244], is usually performed at the end of therapy. However, this approach is being challenged (i) by the knowledge that the speed of tumour cell kill might be relevant particularly in high-grade lymphomas, and (ii) by the application of modern immunological treatments with monoclonal antibodies whose efficacy may last substantially longer than the time period they are infused. Nuclear medicine imaging with positron emission tomography (PET) has become an increasingly used imaging method for the evaluation of lymphoma patients and is capable of more sensitive and accurate staging, early prediction of response and prognosis after 2–3 cycles of chemotherapy, and even predicting the relapse probability after the end of treatment [J Nucl Med47 (2006) 1326]. The main advantages of the technique are based on the detection of tumour-specific metabolic cellular changes. Despite increased sensitivity in many but not all types of lymphoma, PET is not specific for tumour tissue and can be falsely interpreted. Additionally, the therapeutic consequences of the results of radioimaging are poorly defined despite the widespread use of the techniques, raising a number of unsolved problems. This article will review the use of PET and PET/CT in the staging and evaluation of response to therapy in malignant lymphoma and critically assess the pitfalls and advantages of this technique.

The impact of computed tomography (CT) scanning on the accurate diagnosis of malignant lymphoma (ML) and the assessment of the course of disease has rapidly improved over the last years. This is mainly due to the development of multi-slice CT (MSCT) with its unique utility to perform high-resolution full-body scans within a very short period of time. Its standardized sectional views permit excellent comparability to previously performed images with high inter-observer agreement. MSCT is the method of choice for the chest, abdominal and urinary tract regions which is also true with some restrictions to the head and neck region. In the musculoskeletal system the accuracy is lower when compared with magnetic resonance imaging. Among the variety of imaging technologies MSCT plays a central role for staging and restaging of ML with a major impact on therapeutic decisions.