Standardization of Temporal Bone CT Planes across a Multisite Academic Institution.

BACKGROUND AND PURPOSE: Variable head positioning in the CT gantry results in variable and inconsistent temporal bone imaging planes. Our aim was to evaluate whether an automated postprocessing algorithm or an educational intervention with postprocessing by a technologist could result in consistent temporal bone image reformations into planes referenced to the lateral semicircular canal. MATERIALS AND METHODS: Instructions to reformat small-FOV images in planes referenced to the lateral semicircular canal were posted at 12 CT scanner consoles and e-mailed to 65 CT technologists at a single multisite institution. Automated reformatted images were also produced. The angles between the technologist- and automated-reformatted axial image planes and lateral semicircular canal planes were measured. Group differences were calculated with Mann-Whitney-Wilcoxon tests. Differences in homogeneity of variances were calculated with Fligner-Killeen tests. RESULTS: Two hundred ten temporal bones were imaged in 4 months following the intervention. Reformats by technologists were accurate in 87% of the axial and 81% of the coronal planes, with a trend toward improvement with time. Eighty percent of incorrectly reformatted images occurred at off-site, inpatient, and emergency department scanners. The error angle was significantly lower for technologist-reformatted images (median, 4.9°) than for acquisition plane images (median, 14.6°; P = 3 × 10-14) or automated-reformatted images (median, 13.8°; P = 9 × 10-13). The angle error variance was significantly more homogeneous for technologist-reformatted images (P = 3 × 10-8) and automated-reformatted images (P = 1 × 10-5) than for acquisition plane images. CONCLUSIONS: Both technologist and automated reformatting of temporal bone images resulted in significantly less imaging plane variance compared with images reformatted in the acquisition plane, but reformatting by technologists remains necessary at our institution given our preference for standardized planes referencing the lateral semicircular canals.

Hemoperitoneum score helps determine need for therapeutic laparotomy.

PURPOSE: Sonography provides a fast, portable, and noninvasive method for patient assessment. However, the benefit of providing real-time ultrasound (US) imaging and fluid quantification shortly after patient arrival has not been explored. The objective of this study was to prospectively validate a US hemoperitoneum scoring system developed at our institution and determine whether sonography can predict a therapeutic operation. METHODS: For 12 months, prospective data on all patients undergoing a trauma sonogram were recorded. All sonograms positive for free fluid were given a hemoperitoneum score. The US score was compared with initial systolic blood pressure and base deficit to assess the ability of sonography to predict a therapeutic laparotomy. RESULTS: Forty of 46 patients (87%) with a US score > or = 3 required a therapeutic laparotomy. Forty-six of 54 patients with a US score < 3 (85%) did not need operative intervention. The sensitivity of sonography was 83% compared with 28% and 49% for systolic blood pressure and base deficit, respectively, in determining the need for therapeutic operation. CONCLUSION: We conclude that the majority of patients with a score > or = 3 will need surgery. The US hemoperitoneum scoring system was a better predictor of a therapeutic laparotomy than initial blood pressure and/or base deficit.

Noninvasive imaging of cervical vascular injuries.

Various imaging examinations can be used to diagnose cervical vascular injuries. The challenge in the current medical environment is to choose the imaging examination that is the most rapid, least invasive, and least costly. One must recognize the ability of each technique to detect lesions, taking into consideration the type of abnormality and whether the carotid or vertebral arteries are at risk for injury.

Helical CT of cervical spine and soft tissue injuries of the neck.

Helical CT of the neck has revolutionized the diagnostic evaluation of trauma and emergency room patients. This comprehensive examination, with high resolution and fast acquisition times, allows the radiologist to make expeditious diagnoses concerning cervical spine fractures, vascular injuries, and aero-digestive tract lesions. This allows for the more rapid triaging and treatment of various injuries resulting in improved patient priate radiographic examination for each clinical scenario.

Sonography as the primary screening technique for blunt abdominal trauma: experience with 899 patients.

OBJECTIVE: The purpose of this study was to determine the accuracy of sonography when used routinely as the primary screening technique for blunt abdominal trauma. SUBJECTS AND METHODS: From December 1994 through December 1995, we used sonography as the primary screening technique for the initial assessment of blunt abdominal trauma. Sonography was performed by dedicated technologists and overseen and interpreted by radiology residents or attending physicians. A positive study was defined as evidence of free fluid or parenchymal injury. Sonographic findings were correlated with CT, surgery, or clinical follow-up. RESULTS: Of the 899 sonograms obtained for blunt abdominal trauma, the findings of 783 were negative, 101 were positive, and 15 were indeterminate. Of the 783 sonograms with negative findings, 768 (98%) were confirmed by CT, surgery, or clinical follow-up. Similarly, of the 101 sonograms with positive findings, 95 (94%) were confirmed. Interpretations resulted in 15 false-negative and five false-positive examinations. For all sonograms, we calculated a sensitivity of 86%, a specificity of 99%, and an accuracy of 98%. CONCLUSION: Sonography can be used effectively as the primary screening technique for blunt abdominal trauma.

Cervical spine trauma: how much more do we learn by routinely using helical CT?

Assessment of suspected cervical spine injuries remains a major debate in trauma care. It is generally accepted that many fractures are missed or incompletely shown at radiography, mainly because of suboptimal studies obtained in obtunded, uncooperative trauma victims. In a series of 88 severely traumatized patients, the authors retrospectively determined the type, distribution, and significance of such missed lesions. This assessment was made by comparing radiographs and helical computed tomographic (CT) scans of the cervical spine and reviewing medical records in these cases. Of the 88 patients, 32 patients had cervical spine fractures (n = 50) that were not revealed or were incompletely demonstrated at radiography. Most missed fractures occurred at the C-1 to C-2 and C-6 to C-7 levels, and most involved the transverse processes and the posterolateral elements of the vertebrae. One-third of the patients with missed fractures had either clinically significant or unstable injuries, as determined on the basis of mechanistic or imaging criteria. Helical CT can depict significant fractures not shown by plain radiography and should be added routinely to the initial screening for cervical spine fractures in polytrauma victims.

Evaluating blunt abdominal trauma:role for ultrasonography.

Patients in unstable condition with suspected blunt abdominal trauma require rapid evaluation to assess the need for laparotomy. Ultrasonography is fast and uses portable equipment, and it can be used in the resuscitation area to detect free intraperitoneal fluid as an indication of intraabdominal injury in the patient in unstable condition. To determine the utility of emergency abdominal sonography for evaluating patients with blunt abdominal trauma, a prospective study was designed to compare ultrasonography to diagnostic peritoneal lavage. Emergency sonography was performed prior to diagnostic peritoneal lavage on 54 acutely injured patients in the resuscitation area. Our results reveal that ultrasonography has a sensitivity of 87%, a specificity of 100%, and an overall accuracy of 96% for detecting free intraperitoneal fluid. We conclude that ultrasonography is a reliable method for the emergent evaluation of blunt abdominal trauma and can be used in place of diagnostic peritoneal lavage as the initial indicator of significant intraperitoneal injury requiring surgical intervention.

Color Doppler sonography in penetrating injuries of the neck.

PURPOSE: To determine whether color Doppler sonography can be a sensitive alternative to screening arteriography for identifying arterial injury in patients with penetrating traumatic neck injuries. METHODS: Fifty-two patients admitted to our trauma center with penetrating neck injuries (gunshot wounds and lacerations) were examined prospectively with color Doppler sonography, and findings were compared with the results of angiography (n = 44), with findings at surgery (n = 4), and with clinical status (n = 4). RESULTS: Color Doppler sonography correctly detected all serious injuries of the carotid arteries (n = 6; 5 diagnosed at angiography and 1 at surgery) and all injuries of the vertebral arteries (n = 4; all diagnosed at angiography). Sonography missed 1 instance of reversible narrowing of the internal and external carotid arteries and did not show 2 normal vertebral arteries. CONCLUSION: Color Doppler sonography was as accurate as angiography in screening clinically stable patients with zone II or III injuries and no signs of active bleeding. Our initial results suggest that in the future, sonography may be used as a screening examination for arterial lesions in patients with penetrating neck injuries.