The inadequacy of standard radiographs in detecting flaws in the cement mantle.
Radiological assessment of the cement mantle is used routinely to determine the outcome of total hip replacement. We performed a simulated replacement arthroplasty on cadaver femora and took standard postoperative radiographs. The femora were then sectioned into 7 mm slices starting at the calcar, and high-resolution faxitron radiographs were taken of these sections. Analysis of the faxitron images showed that defects in the cement mantle were observed up to 100 times more frequently than on the standard films. We therefore encourage the search for a better technique in assessing the cement mantle. (+info)
Radiography in the home.
Modern portable x-ray units are light enough to be easily carried to the ill patient in his home; their output is sufficient for radiographs containing useful diagnostic information to be made of the chest, hip, and other regions, especially if a grid is employed. The skull is considered to be beyond the range of this method of examination, because of the long exposure times required, but gross lesions can be demonstrated in the oesophagus and stomach if barium is given. The radiation hazard is not considered to be a contraindication if appropriate precautions are taken. (+info)
Safety of radiographic imaging during pregnancy.
Maternal illness during pregnancy is not uncommon and sometimes requires radiographic imaging for proper diagnosis and treatment. The patient and her physician may be concerned about potential harm to the fetus from radiation exposure. In reality, however, the risks to the developing fetus are quite small. The accepted cumulative dose of ionizing radiation during pregnancy is 5 rad, and no single diagnostic study exceeds this maximum. For example, the amount of exposure to the fetus from a two-view chest x-ray of the mother is only 0.00007 rad. The most sensitive time period for central nervous system teratogenesis is between 10 and 17 weeks of gestation. Nonurgent radiologic testing should be avoided during this time. Rare consequences of prenatal radiation exposure include a slight increase in the incidence of childhood leukemia and, possibly, a very small change in the frequency of genetic mutations. Such exposure is not an indication for pregnancy termination. Appropriate counseling of patients before radiologic studies are performed is critical. (+info)
No impact from active dissemination of the Ottawa Ankle Rules: further evidence of the need for local implementation of practice guidelines.
BACKGROUND: Local implementation strategies are often required to promote consistent adherence to clinical guidelines, but they are time consuming and expensive. The authors tested an educational intervention designed to increase use of the Ottawa Ankle Rules, a widely publicized set of clinical guidelines previously shown to reduce the use of radiography for diagnosis of acute ankle injuries. METHODS: The study consisted of a quasi-experimental, before-and-after comparative analysis. Trained experts provided 1-hour educational sessions and supplied resource materials on the Ottawa Ankle Rules to health care professionals from 63 Ontario hospitals. Participants were asked to evaluate the intervention. The authors then compared, for periods before and after the educational sessions, the use of ankle radiography for adults with acute ankle injury in 10 hospitals that received the educational intervention and reported no (n = 5) or some (n = 5) prior use of the rules and in 5 control hospitals, which declined the educational intervention because they were already implementing the rules. RESULTS: Although participants gave highly positive appraisals of the Ottawa Ankle Rules and the educational sessions, there was no reduction in the use of ankle radiography for the 10 hospitals that received the educational sessions (73% before and 78% after the intervention, p = 0.11). In contrast, use of radiography decreased significantly, from 75% to 65%, in the 5 control hospitals (p = 0.022). INTERPRETATION: Even when a dissemination strategy is well received and involves a widely accepted clinical guideline, the impact on behaviour in clinical practice may be small. In addition to broad dissemination, an active local implementation strategy is necessary to encourage physicians to adopt clinical guidelines. (+info)
Anatomy of picture archiving and Communications systems: nuts and bolts--image acquisition: getting digital images from imaging modalities.
Digital acquisition of data from the various imaging modalities for input to a picture archiving and communication system (PACS) is discussed. Essential features for successful clinical implementation including Digital Imaging and Communications in Medicine (DICOM) compliance, radiology information system (RIS)/hospital information system (HIS) interfacing, and workflow integration are detailed. Image acquisition from the inherently digital cross-sectional modalities are described, as well as digital acquisition of the conventional projection x-ray using computed radiography (CR), direct digital radiography (DDR), and film digitizers. (+info)
Prospective survey to verify the Ottawa ankle rules.
OBJECTIVE: To determine if the Ottawa ankle rules are valid in the setting of an urban teaching hospital in the UK. DESIGN: A prospective survey. SETTING: Accident and emergency department, Western Infirmary, Glasgow from 1 April 1995 to 31 August 1995. SUBJECTS: 800 patients with an acute ankle injury. RESULTS: 800 patients were used for analysis of which 584 (73%) were radiographed; 70 (12%) had fractures, 63 (10.8%) of which were significant. Four of these patients with fractures fulfilled none of the Ottawa ankle rules criteria for plain radiography. CONCLUSION: Application of the Ottawa ankle rules to this group of patients would have produced a sensitivity of 93.6%. Although useful, decision rules should be used with care and not replace clinical judgment and experience. (+info)
Radiographic assessment of osteoarthritis: comparison between existing methodologies.
Radiographic sensitivity for quantifying the rate of change in joint space width (JSW) for DMOAD trials, is influenced by the following, which vary between methodologies for imaging hip, knee and hand. Radio-anatomical plane of measurement JSW measurement precision is improve when the (i) joint is in a normal functional position, (ii) X-ray beam is centred on the joint space and (iii) plane of measurement is orthogonal to the beam and articular surfaces, and parallel to the film. Measuring instrument Manual methods, e.g. callipers with graduated magnifying lens or digitisation tablets, suffer from observer variability but are practical and can reliably measure JSW. Computer-based techniques provide precise and accurate JSW measurements. Site of measurement Minimum JSW may lie within the joint's load transmitting region. JSW area and mean area assess the entire JS width. Radiographic magnification This effect is present in hip and knee radiographs and when not corrected, requires increased study numbers. Type of X-ray unit Microfocal radiography's improved spatial resolution increases measurement precision and can decrease study numbers. (+info)
Embedding guidelines into direct physician order entry: simple methods, powerful results.
Kaiser Permanente in the Northwest Region has implemented a comprehensive outpatient computer-based patient record (CPR). Using this system, clinicians electronically order laboratory tests, radiology tests, and prescriptions. Clinicians also use this comprehensive CPR to document encounters, code diagnoses and procedures, maintain problem lists, and to send patient-specific messages and referrals to other medical providers. Healthcare for our entire membership of 440,000 covered lives is now provided through this system . Implementation of a comprehensive CPR with direct physician order-entry provides the opportunity to embed guidelines into the ordering process. This article describes the underlying theme and various simple but effective methods we use to embed guidelines into the ordering process. Our experience demonstrates the powerful effect of these simple methods to reduce unnecessary variation and to reduce cost while maintaining or improving the quality of care delivery. (+info)