Use of portable CT in the R Adams Cowley Shock Trauma Center. Experiences in the admitting area, ICU, and operating room

The author's experience with portable CT has been positive. Nurses and clinical physicians have been pleased with this new imaging capability also, and have written testimonial letters endorsing its value. Recently, the STC extended availability of the mobile CT to the University of Maryland Hospital, an adjoining 600-bed center with numerous medical and surgical patients in ICU. They are particularly interested in assessing use of portable CT in the neonatal ICU, where patient transport outside the unit is particularly difficult and dangerous. Technical improvements for portable CT are in development. Soon, helical volume scanning will be available, allowing faster image acquisition and better two- and three-dimensional image reformations (Fig. 12). A new, more powerful x-ray tube is in development that will permit more slices to be acquired without tube cooling interruptions. Gantry translate capability coupled with a radiolucent backboard extender has the potential to permit scanning of the head, neck, spine, face, and upper torso without the patient being moved from the ICU bed. For applications in head, face, and neck surgery, a radiolucent cranial fixation device also has been developed. Other potential improvements include extended battery power for more scanning between charges, a larger tube heat unit storage for extended scanning situations, decreased system weight for easier transport, and more detector efficiency for improved image quality while maintaining significant dose reduction over conventional scanning. The capability of portable CT scanning for emergency, intensive care, and intraoperative studies exists now. The commercially marketed cost for this system is between $400,000 and $500,000. Further studies are anticipated to clarify the economic and clinical benefits of this technology.     

Renal imaging for diagnosis and staging of renal cell carcinoma

The development and expansion of CT and MRI technology have enhanced the detection and characterization of renal lesions. Although these advancements should lead to earlier diagnosis of renal cell carcinoma with subsequent improved cure rates, the increased imaging has also uncovered many cases that are problematic not only in diagnosis but in management as well. The performance of high-quality examinations combined with growing experience should improve the ability to diagnose and manage these cases successfully. Continued advances in CT and MR technology combined with the current trend toward minimally invasive surgery will continue to expand the role of preoperative imaging and, it is hoped, improve the cure rate of renal cancer.     

The evolution of imaging in advanced prostate cancer

Medical advances will be driven by the enhancement of imaging for diagnosis, refinement of treatment, and evaluation of treatment efficacy. The convergence of technology in materials science, biology, and the computer industry has greatly advanced diagnostic imaging. Precision in control of the spatial and temporal properties of light and its heterogeneous scattering properties have extended our capability for imaging. Refinements in radioimmunoscintigraphy for image acquisition, fusion of images, and outcome data now suggest use for image-guided therapy. Novel MRI agents appear to provide significant imaging capabilities to detect malignant lymph nodes. Future applications of optical coherence tomography, electron paramagnetic resonance imaging, nanotechnology, molecular imaging, and hyperspectral spectroscopy promise further refinements to image tissues for diagnosis.     

Update on functional imaging in the evaluation of diabetic foot infection

Diabetic foot infection is a preventable complication of diabetes mellitus. It is an essential component of diabetic foot disease, which is characterised by a triad of neuropathy, ischaemia and infection. These factors may lead to foot ulceration, sepsis and amputation resulting in increased morbidity and poor quality of life. Confirming or excluding infection can be difficult especially when routine laboratory tests and plain radiographs are inconclusive. Early diagnosis and localization of diabetic foot infection is extremely important to institute timely, appropriate therapy. Structural imaging using computed tomography and magnetic resonance imaging all have individual applications towards the diagnostic workup of this condition but have their own limitations. Scintigraphic detection is based on physiochemical changes and hence provides a functional evaluation of bone pathology.We describe the evolution of functional nuclear medicine imaging including immunoscintigraphy in diabetic foot infection and highlight current applications of physiological 18-Fluoro-deoxyglucose positron emission tomography (18-FDG-PET) and computed tomography (18-FDG-PET/CT) in such patients.18-FDG-PET/CT is a promising modality for imaging diabetic foot infection. Future studies will allow standardisation of technological details and options of 18-FDG-PET/CT interpretation in diabetic foot infection.     

Fiberoptic imaging for urologic surgery

Laparoscopic and robot-assisted surgery is likely to be improved with the development of real-time, intraoperative imaging for diagnosis, margin determination, and anatomical definition. A significant goal of much of this effort has been focused upon providing better outcomes after radical prostatectomy. The feasibility of fluorescent imaging of labeled cavernosal nerves in the operative field has been demonstrated in vivo in animals. Other applications of the technology and capability will certainly be developed over time. This article reviews and assesses the potential and capabilities of the different imaging modes currently in use or development.     

Magnetic resonance imaging contrast agents: theory and application to the central nervous system

The theoretical aspects of magnetic resonance (MR) imaging contrast agents are reviewed, and their current applications to the central nervous system (CNS) and their future applications are discussed. Profound differences exist between contrast agents used for MR imaging and computerized tomography (CT). In MR imaging, the contrast agents are not imaged directly but rather act on adjacent protons to shorten T1 and T2 relaxation times. This in turn results in signal intensity changes. The lanthanide metal, gadolinium, in the form of gadopentetate dimeglumine, has been found to be both safe and efficacious as the only currently approved contrast agent for MR imaging. Magnetic resonance imaging revolutionized the detection and treatment of disease affecting the brain and spine. Initially, it was thought that signal characteristics on MR imaging would allow differentiation of specific pathology. It was soon found that MR studies were able to detect more abnormalities but were less able to characterize them. The recent development of contrast agents for MR imaging has allowed this modality to surpass CT for the evaluation of most CNS lesions. At present, contrast-enhanced MR imaging is generally accepted as the study of choice for evaluating acoustic neurinomas, pituitary lesions, meningeal disease, primary and secondary brain tumors, active multiple sclerosis, intradural spinal neoplasms, intramedullary spinal disease, and postoperative states in both the spine and brain. Even when contrast-enhanced CT can detect the same abnormalities, evaluation of the lesions in multiple planes on MR imaging can sometimes yield invaluable information, especially prior to surgery. Future developments of contrast material for MR imaging include non-gadolinium compounds, intrathecal contrast media, cerebral blood flow and volume evaluation, and, possibly, antibody-labeled contrast agents.     

Aspects of neuroradiology of head injury.

One of the paramount concerns in head injury is why there is such a disparity in recovery from injuries that appear clinically similar. CT scan has established itself as the primary imaging modality for acute head injury, and acute hemorrhages are readily identified allowing for prompt surgical intervention. However, CT has proven to be of little value in predicting the outcome of patients with diffuse nonhemorrhagic white-matter injury. Future research with MR imaging during the acute phase as well as continued work in the subacute and chronic phases will undoubtedly prove this modality useful in more precise prediction of outcome in patients with head injuries.     

PET-CT scan: a major progress toward fused, metabolic and functional images

Positron emission tomography (PET) is an imaging method that allows metabolic mapping of disease processes after a specific radiotracer administration. One of the major disadvantages of using radioactive glucose is the fact that this radiotracer is not entirely specific for tumor tissue. Also, the physiological distribution of 18F FDG makes difficult the anatomical localization. Computed tomography (CT) provides en excellent anatomic resolution but the functional information is reduced. In this circumstances PET and CT gives complementary information, and together increase the lesions localization and reduce the artifacts of interpretation. That was exactly the purpose for building the new hybrid gamma camera PET-CT. The new concept of hardware fusion between PET and CT is now commercially available from five years. By the meaning of fused anatomic and functional imaging PET-CT has already found a number of clinical applications in oncology. The new imaging technology reduces image acquisition time, improves tumor localization which is difficult if not impossible with PET alone, and calculate more accurate the target tumor volume for radiotherapy planning. This article is a review from literature data, concerning the mean indications, weaknesses, current evidence and future directions of PET-CT. In Romania, there are not available either PET or PET-CT. We believe that the aspiration at the European standards will remedy it as soon as possible.     

Preoperative planning for renal cell carcinoma--benefits of 64-slice CT imaging

Surgery is the primary form of treatment in localized renal cell carcinoma. Adrenal-sparing nephrectomy, laparoscopic nephrectomy and nephron-sparing partial nephrectomy are growing trends for more limited surgical resection. Accurate preoperative imaging is essential for planning the surgical approach. Multislice CT and MR are regarded as the most efficient modalities for imaging renal neoplasms. Development of faster CT systems like 64-slice CT with improved resolution and capability to achieve isotropic reformats have significantly enhanced the role of CT in imaging of renal neoplasms. This review article describes the present state, technique and benefits of 64-slice CT scanning in preoperative planning for RCC.     

Contemporary Imaging of the Renal Mass

Renal masses increasingly are detected incidentally in asymptomatic individuals. Accurate characterization of these lesions is important for clinical management, planning intervention, and avoiding unnecessary procedures. Ultrasonography, computed tomography (CT), and magnetic resonance imaging (MRI) are the mainstays of renal mass detection and characterization. Ultrasonography is useful for distinguishing cystic from solid lesions and can detect lesion vascularity, especially with use of ultrasound contrast agents, but is less sensitive, less specific, and less reproducible than CT and MRI. CT, with and without intravenous contrast, is the primary imaging test for characterization and staging of renal lesions, and is utilized more often than MRI. Current multidetector CT technology provides near isotropic acquisition, with three-dimensional reformatting capabilities. Due to lack of exposure to iodinated contrast and ionizing radiation and superior soft tissue contrast, MRI is being increasingly utilized as a problem-solving tool for diagnosis, staging, and preoperative planning for renal malignancies. Future directions for imaging of primary renal neoplasm include accurate characterization of renal cell cancer subtype, assistance with treatment planning, and evaluation of treatment response.     

Zukunft der Radiologie

More than other medical discipline, radiology is marked by technical innovation and continuous development, as well as the optimization of the underlying physical principles. In this respect, several trends that will crucially change and develop radiology over the next decade can be observed. Through the use of ever faster computer tomography, which also shows an ever-decreasing radiation exposure, the ?workhorse“ of radiology will have an even greater place and displace conventional X?ray techniques further. In addition, hybrid imaging, which is based on a combination of nuclear medicine and radiological techniques (keywords: PET/CT, PET/MRI) will become much more established and, in particular, will improve oncological imaging further, allowing increasingly individualized imaging for specific tracers and techniques of functional magnetic resonance imaging for a particular tumour. Future radiology will be strongly characterized by innovations in the software and Internet industry, which will enable new image viewing and processing methods and open up new possibilities in the context of the organization of radiological work.     

Multiple sclerosis--Part 2. Treatment strategies

Because it is a chronic, relapsing or progressive disease, multiple sclerosis has an unpredictable clinical course generally spanning 10 to 20 years. During that time, neurologic disability is cumulative. Therefore, it is difficult to evaluate the efficacy of a given mode of treatment in an individual patient. This second part of a two-part series reviews current and emerging modes of therapy for multiple sclerosis. Future treatment directions in multiple sclerosis will require a better understanding of the pathophysiology of the disease. Future therapeutic modalities will also rely on more accurate clinical markers, such as improved magnetic resonance imaging techniques or specific immune markers to follow the disease progression. Part 1 of this series appearing in the November 1999 issue of JAOA included several sections on multiple sclerosis, including an overview, pathophysiology, diagnostic evaluation, and clinical parameters.     

Neurosurgery in the realm of 10(-9), part 1: stardust and nanotechnology in neuroscience

Nanotechnology as a science has evolved from notions and speculation to emerge as a prominent combination of science and engineering that stands to impact innumerable aspects of technology. Medicine in general and neurosurgery in particular will benefit greatly in terms of improved diagnostic and therapeutic capabilities. The recent explosion in nanotechnology products, including diverse applications such as beauty products and medical contrast agents, has been accompanied by an ever increasing volume of literature. Recent articles from our institution provided an historical and scientific background of nanotechnology, with a purposeful focus on nanomedicine. Future applications of nanotechnology to neuroscience and neurosurgery were briefly addressed. The present article is the first of two that will further this discussion by providing specific details of current nanotechnology applications and research related to neuroscience and clinical neurosurgery. This article also provides relevant perspective in scale, history, economics, and toxicology. Topics of specific importance to developments or advances of technologies used by neuroscientists and neurosurgeons are presented. In addition, advances in the field of microelectromechanical systems technology are discussed. Although larger than nanoscale, microelectromechanical systems technologies will play an important role in the future of medicine and neurosurgery. The second article will discuss current nanotechnologies that are being, or will be in the near future, incorporated into the armamentarium of the neurosurgeon. The goal of these articles is to keep the neuroscience community abreast of current developments in nanotechnology, nanomedicine, and, in particular, nanoneurosurgery, and to present possibilities for future applications of nanotechnology. As applications of nanotechnology permeate all forms of scientific and medical research, clinical applications will continue to emerge. Physicians of the present and future must take an active role in shaping the design and research of nanotechnologies to ensure maximal clinical relevance and patient benefit.     

The evolution of three-dimensional technology in musculoskeletal oncology

Musculoskeletal tumours pose considerable challenges for the orthopaedic surgeon during pre-operative planning, resection and reconstruction. Improvements in imaging technology have improved the diagnostic process of these tumours. Despite this, studies have highlighted the difficulties in achieving consistent resection free margins especially in tumours of the pelvis and spine when using conventional methods. Three-dimensional technology – three-dimensional printing and navigation technology – while relatively new, may have the potential to prove useful in the musculoskeletal tumour surgeon's arsenal. Three-dimensional printing (3DP) allows the production of objects by adding material layer by layer rather than subtraction from raw materials as performed conventionally. High resolution imaging, computer tomography (CT) and magnetic resonance imaging (MRI), are used to print highly complex and accurate items. Powder-based printing, vat polymerization-based printing and droplet-based printing are the common 3DP technologies applied. 3DP has been utilized pre-operatively in surgical planning and intra-operatively for patient specific instruments and custom made prosthesis. Pre-operative 3DP models transfer information to the surgeon in a concise yet exhaustive manner. Patient specific instruments are customized 3DP instruments utilized with the intention to easily replicate surgical plans. Complex musculoskeletal tumours pose reconstructive challenges and standard implants are often unable to reconstruct defects satisfactorily. The ability to use custom materials and tailor the pore size, elastic modulus and porosity of the 3DP prosthesis to be comparable to the patient's bone allows for a potential patient-specific prosthesis with unique incorporation and longevity properties. Similarly, navigation technology utilizes CT or MRI images to provides surgeons with real time intraoperative three-dimensional calibration of instruments. It has been shown to potentially allow surgeons to perform more accurate resections. These technological advancements have the potential to greatly impact the management of musculoskeletal tumours. 3D planning models, patient-specific instruments and customized 3DP implants and navigation should not be thought of as separate, but rather, patient-specific adaptation of relevant modes of application should be selected on a case-by-case basis when taking all unique factors of each case into consideration.     

Basics of computed tomography angiography of the lower extremity vessels

Complete noninvasive, angiographic evaluation of the abdominal aorta and lower extremity vessels using the latest generation of multidetector row computed tomography (CT) scanners can now be accomplished in a single scan lasting less than a minute. The high spatial resolution of these new scanners and their more efficient use of contrast permit accurate depiction of disease in the smaller tibial and pedal vessels, as well as the larger diameter iliac and femoral arteries; nevertheless, many challenges and obstacles remain to its more widespread acceptance. Foremost among these, is the difficulty in accurately reconstructing the smaller leg and pedal vessels from individual CT slices, a process that must to a very great extent be done manually, and the potential nephrotoxicity of iodinated contrast material. Future advances in imaging software that could more fully automate accurate three-dimensional reconstructions of the lower extremity vasculature, and detector technology to allow for even finer resolution of the vasculature will further enhance an already powerful and clinically useful tool.     

Advances in computer imaging/applications in facial plastic surgery

Rapidly progressing computer technology, ever-increasing expectations of patients, and a confusing medicolegal environment requires a clarification of the role of computer imaging/applications. Advances in computer technology and its applications are reviewed. A brief historical discussion is included for perspective. Improvements in both hardware and software with the advent of digital imaging have allowed great increases in speed and accuracy in patient imaging. This facilitates doctor-patient communication and possibly realistic patient expectations. Patients seeking cosmetic surgery now often expect preoperative imaging. Although society in general has become more litigious, a literature search up to 1998 reveals no lawsuits directly involving computer imaging. It appears that conservative utilization of computer imaging by the facial plastic surgeon may actually reduce liability and promote communication. Recent advances have significantly enhanced the value of computer imaging in the practice of facial plastic surgery. These technological advances in computer imaging appear to contribute a useful technique for the practice of facial plastic surgery. Inclusion of computer imaging should be given serious consideration as an adjunct to clinical practice.     

The operating room of the future: a view from Europe

The Operating Room of the Future will be characterized by meticulous preoperative planning, full integration of the operating room into the general flow of information, more comprehensive intraoperative diagnostic imaging procedures, and the use of sophisticated visualization processes including augmented reality. Mechatronic support (partially autonomous robots) enhances safety and allows reduction of staff. Integrated operating room systems will allow the wide spectrum of new devices and functionalities to be easily controlled by the operating team. The Operating Room of the Future will no longer be isolated from the rest of the clinical endeavor. Intraoperative teleconsultation and telepresence will help to promote and teach safer evidence-based endoscopic therapeutic surgery. Traditional surgical intervention will expand its definitions by procedures via an interdisciplinary, cooperative approach that will replace the sequential therapeutic process of today.     

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??Imageology features and assessment of gallbladder carcinoma HUANG Sui-qiao. Department of Radiation, Sun Yat-sen Memorial Hospital of Sun Yat-sen University, Guangzhou 510120, China
Abstract There are many imaging methods in detecting gallbladder carcinoma. Ultrasonography is the most common imaging method now, but the applications of CT and MRI are increased gradually and shown very important in diagnosing gallbladder carcinoma in clinical practice. 18F-FDG PET-CT has very high specificity and can be used in diagnosing difficult cases. It is not difficult for diagnosing typical gallbladder carcinoma, but it is not easy to diagnose early stage of gallbladder carcinoma. The applications of CDFI, contrast-enhanced ultrasound, dynamic CT and MRI scanning, DWIBS technique and 18F-FDG PET-CT will hopefully increase correct diagnosing level for early stage of gallbladder carcinoma. CT and MRI are better in demonstrating invasion of near structures and lymph node involvement due to gallbladder carcinoma. But lymph node involvement can easily get missed diagnosis just based on the size of lymph node. The shortages would be improved by 18F-FDG PET-CT and DWIBS technique.     

The physician-owned imaging center

The advent of advanced imaging modalities in the past 20 years represents a paradigm shift as physicians seek new ways to offer earlier diagnosis and treatment and to augment practice service and revenues. A physician-owned, office-based imaging project has evolved from conventional X ray to more advanced imaging, which includes MRI, CT, and other digital imaging methods. Orthopedic practices need to do a thorough analysis to match the technology and type of unit to the patient volume and prospective payment for the services rendered. This analysis should include understanding the capability and limitations of the MRI or other imaging modality selected, staffing, siting, and teleradiology interpretations. This article elucidates this general trend in orthopedic imaging and examines practical aspects of the physician/practice-owned imaging center.     

C臂CT在神经介入中的应用进展

C臂CT是平板探测器数字减影血管造影系统上的一种新技术,随着成像技术的改进,C臂CT系统功能不断增强,已被广泛应用于神经介入术,其在支架显影成像、软组织成像、灌注成像方面的应用给神经介入带来了极大的便利。本文对C-臂CT系统在神经介入中应用的最新进展以及其对临床工作的巨大指导意义进行综述。