Thomas Ptak

Experience with a continuous, single-pass whole-body multidetector CT protocol for trauma: the three-minute multiple trauma CT scan

Purpose: To test the clinical feasibility and utility of a single-pass, whole-body multidetector CT (MDCT) protocol in the evaluation of the multiple trauma patient. Materials and methods: A whole-body, single-pass MDCT protocol was designed for optimal imaging quality and maximum flexibility for retrospective reconstruction and multiplanar reformation. Five consecutive trauma patients with moderate to severe mechanisms of injury were scanned on an MDCT scanner using the single-pass protocol. Times were recorded for the scan alone and for time spent in the CT bay. Times were compared with those for five random trauma patients scanned on a single-detector helical CT (SDHCT) scanner who were matched for body segments imaged and trauma severity. Results: Compared to SDHCT, MDCT scan times were shortened by a factor of 10 (3 min for MDCT vs 41 for SDHCT) and patient throughput times by a factor of 3 (23 min for MDCT vs 65 for SDHCT). Image quality was mildly compromised in MDCT by beam hardening due to arm position, but overall was comparable to segmental imaging. Conclusion: Whole-body MDCT is feasible and offers a marked time advantage over conventional segmental imaging in multiple trauma patients. Added flexibility through reformation of image data allows imaging evaluation as needed even after the patient has left the scanner bay.

Screening for cervical spine trauma with helical CT: experience with 676 cases

Purpose: CT scanners with helical capability are commonplace. Evaluation of multiple trauma patients using this technique is fast, and easily performed as part of the radiological evaluation. Our purpose was to ascertain the clinical effectiveness of cervical spine screening with helical CT in a large sample population of multitrauma patients. Materials and methods: A retrospective review was carried out using screening helical CT scans from multitrauma patients referred to the Massachusetts General Hospital emergency department. The radiographic diagnosis was evaluated and tallied along with the clinical diagnosis and outcome for each patient included in the study. Results: Six hundred seventy-six patients conformed to the inclusion criteria. In this series, 59 true-positive, 616 true-negative, 1 false-negative, and no false-positive findings were encountered. These data result in a sensitivity of 98.3 %, a specificity of 100 %, and an accuracy of 99.9 %. Conclusions: Screening helical CT in the evaluation of trauma patients has a high diagnostic accuracy, and is sensitive and specific in diagnosing clinically relevant fractures of the cervical spine.

Should an MR scan be performed routinely after a normal clearance CT scan in the trauma patient? Experience with 59 cases

Abstract Magnetic resonance (MR) imaging is not routinely used to exclude ligamentous and other soft tissue injury in the unconscious trauma patient. In order to determine the frequency and types of soft tissue injuries detected by MR imaging but not by computed tomography (CT), we performed a retrospective investigation comparing the MR findings in 59 trauma patients, either alert or unconscious, who previously had undergone a negative clearance multislice CT study of the cervical spine. Six patients had abnormalities not identified on the CT studies, including four cases of ligamentous injury.

Can CT eliminate the initial portable lateral cervical spine radiograph in the multiple trauma patient? A review of 200 cases

Purpose: This investigation examines whether there is a continued role for the initial screening lateral portable radiograph in patients whose cervical spine is “cleared” by a CT examination. Methods: A retrospective review of 200 multiple trauma patients suspected of cervical spine injury (CSI) was performed. All patients had a screening lateral portable cervical spine radiograph (LPCSR) followed by cervical spine CT (CSCT). All scans were helical and included coronal and sagittal reformations. Reports of both examinations were compared for all patients. For those patients with signs of acute CSI, the two reports were compared to determine whether the LPCSR contained any information affecting patient outcome that was not detected by CSCT. Results: The CSCT showed no signs of acute CSI injury in 190 patients. Ten CSCT scans showed signs of fracture. In these 10 patients, the screening LPSCR showed signs of fracture in 1 patient, question of fracture in 2 patients, and no fracture in 7 patients. No LPCSR demonstrated significant information not seen on the accompanying CSCT. No LPSCR showed a finding that altered patient management prior to CSCT. Conclusion: The data suggest that an initial LPCSR is unnecessary if the patient is having a screening CSCT.

Imaging of head trauma

Imaging is an indispensable part of the initial assessment and subsequent management of patients with head trauma. Initially, it is important for diagnosing the extent of injury and the prompt recognition of treatable injuries to reduce mortality. Subsequently, imaging is useful in following the sequelae of trauma. In this chapter, we review indications for neuroimaging and typical computed tomography (CT) and magnetic resonance imaging (MRI) protocols used in the evaluation of a patient with head trauma. We review the role of CT), the imaging modality of choice in the acute setting, and the role of MRI in the evaluation of patients with head trauma. We describe an organized and consistent approach to the interpretation of imaging of these patients. Important topics in head trauma, including fundamental concepts related to skull fractures, intracranial hemorrhage, parenchymal injury, penetrating trauma, cerebrovascular injuries, and secondary effects of trauma, are reviewed. The chapter concludes with advanced neuroimaging techniques for the evaluation of traumatic brain injury, including use of diffusion tensor imaging (DTI), functional MRI (fMRI), and MR spectroscopy (MRS), techniques which are still under development.

CT pitfalls in emergency radiology: a chronically ruptured intra-cranial dermoid tumor mimicking pneumocephalus in an acute multi-trauma evaluation

Traumatic rupture of an intracranial dermoid tumor is an unusual event. In this case, however, a ruptured intracranial dermoid is noted, but in the absence of clinical signs and symptoms. The lack of symptoms coupled with an abnormal cerebral computed tomography (CT) initially created confusion among clinicians until a more detailed history and more careful analysis of the head CT revealed the plausible answer.

ACR Appropriateness Criteria® Penetrating Neck Injury

In patients with penetrating neck injuries with clinical soft injury signs, and patients with hard signs of injury who do not require immediate surgery, CT angiography of the neck is the preferred imaging procedure to evaluate extent of injury. Other modalities, such as radiography and fluoroscopy, catheter-based angiography, ultrasound, and MR angiography have their place in the evaluation of the patient, depending on the specific clinical situation and question at hand. The ACR Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer-reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.

ACR Appropriateness Criteria® Sudden Onset of Cold, Painful Leg

Acute limb ischemia (ALI) requires urgent diagnosis and treatment to prevent limb loss. Invasive digital subtraction arteriography (DSA) is the gold standard for diagnosing ALI. DSA is the only diagnostic modality that permits simultaneous treatment of acute arterial occlusion. Noninvasive imaging with MRA or CT angiography may also be appropriate before treatment, especially when the diagnosis of ALI is in doubt or where DSA is unavailable. Other imaging and noninvasive physiologic tests may prove important for longer term management but are less recommended in the acute setting. The American College of Radiology Appropriateness Criteria are evidence-based guidelines for specific clinical conditions that are reviewed annually by a multidisciplinary expert panel. The guideline development and revision include an extensive analysis of current medical literature from peer reviewed journals and the application of well-established methodologies (RAND/UCLA Appropriateness Method and Grading of Recommendations Assessment, Development, and Evaluation or GRADE) to rate the appropriateness of imaging and treatment procedures for specific clinical scenarios. In those instances where evidence is lacking or equivocal, expert opinion may supplement the available evidence to recommend imaging or treatment.