Lumbar fractures in adult blunt trauma: axial and single-slice helical abdominal and pelvic computed tomographic scans versus portable plain films

BACKGROUND: Our hypothesis was that abdominal and pelvic computed tomographic (AP-CT) scans are equivalent to portable two-view plain films in detecting lumbar spine fractures in adults. Since many trauma patients often undergo AP-CT scanning to evaluate for possible intra-abdominal injuries, using the AP-CT scan to screen for lumbar fractures could make the trauma evaluation process more efficient. METHODS: The institutional trauma registry at a Level I trauma center was used to identify all blunt lumbar fractures during a 6-year period. Medical records were reviewed. RESULTS: A total of 7,216 adult blunt trauma patients were evaluated, and 115 patients were identified as having a lumbar fracture, for an incidence rate of 1.6%. Missed fracture rates were high for both AP-CT scans (23.2%, 13 of 56) and portable two-view films (12.7%, 14 of 110, = 0.08). Fifty-two patients had both AP-CT scans and plain films. In this group, AP-CT scans missed 23.1% (12 of 52) of the lumbar fractures and plain films missed 15.4% (8 of 52). However, the combination of the two diagnostic methods did not miss any fractures (0 of 52). The missed fractures required surgery or brace in 50% (7 of 14) patients who had fractures missed by plain films and 46% (6 of 13) patients whose fractures were missed by AP-CT scanning. CONCLUSION: Both AP-CT scans and plain films failed to diagnose significant lumbar fractures that required therapy. When screening for lumbar fractures, obtaining both AP-CT scans and portable two-view plain films may decrease missed lumbar fractures in blunt adult trauma.     

Eating in space--from an astronaut's perspective

Food systems and meal components are constantly under review and development at the National Aerospace and Space Administration. The goal of this work is to generate a diet that meets the nutrient requirements of astronauts and satiates them. The constraints involved in shorter- and longer-term missions are described. The insight provided by observations of astronauts from the Skylab and Shuttle eras will allow researchers to consider the fact that, for any nutritional regimen to work, it must consider the limitations and taste buds of the individuals involved. Otherwise, the best diet design generated by their work may never be consumed.     

Cost-savings analysis of an outpatient management program for women with pregnancy-related hypertensive conditions.

The aim of this study was to evaluate the cost savings of outpatient management services for women with pregnancy-related hypertensive conditions. The outpatient management program included verbal and written patient education related to the hypertensive disease process during pregnancy as well as self-care procedures. Biometric data (ie, automated blood pressure measurement, qualitative urine protein) were collected at least daily by the patient and transmitted telephonically to a nursing call center. Data were evaluated and subjective symptoms assessed daily. Electronic records were maintained and reports provided to the prescribing physician and case manager. Included for analysis were: patients with pregnancy-related hypertensive conditions receiving outpatient services between January 1999 and November 2003, singleton gestation, no history of chronic hypertension, and gestational age of 20.0-36.9 weeks at start of outpatient program (n = 1,140). Maternal characteristics, antenatal hospitalization and length of stay, progression of disease, and neonatal outcome were analyzed. To evaluate cost-effectiveness, a model was developed to compare the cost of the program plus adjunctive antenatal hospitalization, to control data. The mean gestational age at program start was 32.6 weeks. Antenatal hospital admission was required for 24.8% of patients, with a mean length of stay of 2.3 days per admission. Progression to severe preeclampsia occurred in 14.3% of patients. Mean gestational age at delivery was 37.0 weeks. Antepartum charges averaged 10,327 US dollars per control patient and 4,888 US dollars per program patient, a difference of 5,439 US dollars. For each dollar spent on outpatient management, an average of 2.50 US dollars was saved. Utilizing outpatient management services for women with pregnancy-related hypertension reduces the need for inpatient care and is cost-effective.     

Quality assessment and assurance in diagnostic imaging. Theoretical and practical considerations and a quality audit of the excretory urogram

Concepts necessary to an understanding of the basics of quality assurance audits are presented. Included are specific examples that bridged theory and practice by applying the protocol to a real-life diagnostic imaging situation. This method meets the present requirements of the Joint Commission of the Accrediation of Hospitals.     

Distinct patterns of stimulus generalization of increases and decreases in VOR gain

Motor learning must be capable of increasing or decreasing the amplitude of movements to meet the demands of the environment. One way to implement such opposite learned changes would be to store them with bidirectional plasticity mechanisms (i.e., long-term potentiation and depression at the same synapses). At the behavioral level, this scheme should result in similar patterns of stimulus generalization of increases and decreases in movement amplitude because the same synapses would be modified but in opposite directions. To test this idea, we quantitatively compared the stimulus generalization of learned increases and decreases in the gain (amplitude) of the vestibuloocular reflex (VOR) in mice and in monkeys. When examined across different sinusoidal frequencies of head rotation, decreases in VOR gain generalized more than increases in gain. This difference was apparent not only in the gain, but also the phase (timing) of the VOR. Furthermore, this difference held when animals were trained with high-frequency rotational stimuli, a manipulation that enhances frequency generalization. Our results suggest that increases and decreases in VOR gain are not exact inverses at the circuit level. At one or more sites, the plasticity mechanisms supporting decreases in VOR gain must be less synapse-specific, or affect neurons more broadly tuned for head rotation frequency, than the mechanisms supporting increases in gain.     

How to simplify the CT diagnosis of Le Fort fractures

OBJECTIVE: The numerous components seen in the Le Fort fractures make classification difficult. Our objective is to simplify the task of classifying Le Fort fractures. CONCLUSION: Each of the Le Fort fractures has at least one unique component that is easily recognizable: I, the anterolateral margin of the nasal fossa; II, the inferior orbital rim; and III, the zygomatic arch. Classification of the Le Fort fractures is simplified by using these unique components to establish a tentative classification that is then confirmed.     

The likelihood of adverse outcomes in triplet pregnancies estimated by pregravid maternal characteristics

OBJECTIVE: To estimate the likelihood of adverse outcomes in triplet pregnancies by a score comprising pregravid maternal characteristics. DESIGN: A cross-sectional study. SETTING: Triplets database collected by Matria Healthcare, Inc. PATIENT(S): A scoring system was constructed, assigning 1 point for the presence of a risk factor (nulliparity, stature <165 cm, and age <35 years) and 0 for the absence of a risk factor. Data related to 2,887 triplet sets were analyzed. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Total triplet birth weight <4,500 and delivery at 27-32 weeks. RESULT(S): We identified 18% of triplets' mothers (score 3) in whom the likelihood for adverse results is 50%-90% higher and the likelihood for optimal results is 40% to 70% lower than background rates. CONCLUSION(S): A pregravid maternal profile could estimate the likelihood of adverse outcomes and be used for consulting patients at risk of having or carrying a triplet pregnancy.     

Comparison of image quality between conventional and low-dose nonenhanced head CT

BACKGROUND AND PURPOSE: Increasing use of CT for evaluating neurologic disease may expose patients to considerable levels of ionizing radiation. We compared the image quality of low-mAs head CT scans with that of conventional nonenhanced scans. METHODS: Conventional head CT scans were obtained in 20 patients (all >65 years with history of non-CNS malignancy) by using a multidetector technique: 170 mA and 1-second scanning time (ie, 170 mAs), 140 kVp, table speed of 7.5 mm per rotation, pitch of 0.75, section thickness of 5 mm, and field of view of 25 mm. A limited volume helical data acquisition covering four 5-mm-thick images was obtained by using 90 mAs but otherwise the same parameters. Three neuroradiologists visually rated the resulting images for quality in a blinded comparison. Representative 1- to 4-mm(2) regions of interest were chosen in gray matter and white matter locations. Conspicuity and the contrast-to-noise ratio were analyzed. Statistical comparisons were done by using the Student t test. RESULTS: Mean gray matter conspicuity was not significantly different between the 170- and 90-mAs groups (0.39 +/- 0.19 vs 0.41 +/- 0.03, P =.32). Mean gray matter contrast-to-noise ratio was approximately 22% higher with 170 mAs than with 90 mAs (1.77 +/- 0.52 vs 1.39 +/- 0.38, P =.005). All 90-mAs images were rated as having slightly greater image noise than the 170-mAs scans but with sufficient perceived resolution. CONCLUSION: Although 90-mAs head CT images were moderately noisier than 170-mAs images, they were rated as having acceptable diagnostic quality.