Canadian Association of Radiologists Trauma Diagnostic Imaging Referral Guideline

The Canadian Association of Radiologists (CAR) Trauma Expert Panel consists of adult and pediatric emergency and trauma radiologists, emergency physicians, a family physician, a patient advisor, and an epidemiologist/guideline methodologist. After developing a list of 21 clinical/diagnostic scenarios, a systematic rapid scoping review was undertaken to identify systematically produced referral guidelines that provide recommendations for 1 or more of these clinical/diagnostic scenarios. Recommendations from 49 guidelines and contextualization criteria in the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) for guidelines framework were used to develop 50 recommendation statements across the 21 scenarios related to the evaluation of traumatic injuries. This guideline presents the methods of development and the recommendations for head, face, neck, spine, hip/pelvis, arms, legs, superficial soft tissue injury foreign body, chest, abdomen, and non-accidental trauma.

A real-world demonstration of machine learning generalizability in the detection of intracranial hemorrhage on head computerized tomography

Machine learning (ML) holds great promise in transforming healthcare. While published studies have shown the utility of ML models in interpreting medical imaging examinations, these are often evaluated under laboratory settings. The importance of real world evaluation is best illustrated by case studies that have documented successes and failures in the translation of these models into clinical environments. A key prerequisite for the clinical adoption of these technologies is demonstrating generalizable ML model performance under real world circumstances. The purpose of this study was to demonstrate that ML model generalizability is achievable in medical imaging with the detection of intracranial hemorrhage (ICH) on non-contrast computed tomography (CT) scans serving as the use case. An ML model was trained using 21,784 scans from the RSNA Intracranial Hemorrhage CT dataset while generalizability was evaluated using an external validation dataset obtained from our busy trauma and neurosurgical center. This real world external validation dataset consisted of every unenhanced head CT scan (n = 5965) performed in our emergency department in 2019 without exclusion. The model demonstrated an AUC of 98.4%, sensitivity of 98.8%, and specificity of 98.0%, on the test dataset. On external validation, the model demonstrated an AUC of 95.4%, sensitivity of 91.3%, and specificity of 94.1%. Evaluating the ML model using a real world external validation dataset that is temporally and geographically distinct from the training dataset indicates that ML generalizability is achievable in medical imaging applications.

Massive traumatic abdominal wall hernia with significant tissue loss: challenges in management

A 41-year-old woman presented to our trauma centre following a high-speed motor vehicle collision with a seatbelt pattern of injury resulting in extensive rupture of her abdominal wall musculature and associated hollow viscus injuries. The abdominal wall had vertical separation between transected rectus, bilateral transverse abdominis and oblique muscles allowing evisceration of small and large bowel into the flanks without skin rupture. Intraoperatively, extensive liquefaction and tissue loss of the abdominal wall was found with significant retraction of the remaining musculature. Initial operative management focused on repair of concomitant intra-abdominal injuries with definitive repair performed in delayed, preplanned stages including bridging with absorbable mesh and placement of an overlying split-thickness skin graft. The patient was discharged from hospital and underwent extensive rehabilitation. One year later, the abdominal wall was definitively repaired with components separation and biological mesh underlay. This stepwise repair process provided her with a robust and enduring abdominal wall reconstruction.

Cost benefit analysis of portable chest radiography through glass: Initial experience at a tertiary care centre during COVID-19 pandemic

Introduction

Portable chest radiography through glass (TG-CXR) is a novel technique, particularly useful during the COVID-19 (Coronavirus disease 2019) pandemic. The purpose of this study was to understand the cost and benefit of adopting TG-CXR in quantifiable terms.

Methods

Portable or bedside radiographs are typically performed by a team of two technologists. The TG-CXR method has the benefit of allowing one technologist to stay outside of the patient room while operating the portable radiography machine, reducing PPE use, decreasing the frequency of radiography machine sanitization and decreasing technologists’ exposures to potentially infectious patients. The cost of implementing this technique during the current COVID-19 pandemic was obtained from our department's operational database. The direct cost of routinely used PPE and sanitization materials and the cost of the time taken by the technologists to clean the machine was used to form a quantitative picture of the benefit associated with TG-CXR technique.

Results

Technologists were trained on the TG-CXR method during a 15 min shift change briefing. This translated to a one-time cost of $424.88 USD. There was an average reduction of portable radiography machine downtime of 4 min and 48 s per study. The benefit of adopting the TG-CXR technique was $9.87 USD per patient imaged. This will result in a projected net cost savings of $51,451.84 USD per annum.

Conclusion

Adoption of the TG-CXR technique during the COVID-19 pandemic involved minimal one-time cost, but is projected to result in a net-benefit of over $51,000 USD per annum in our emergency department.

Proof of Concept: Phantom Study to Ensure Quality and Safety of Portable Chest Radiography Through Glass During the COVID-19 Pandemic

BACKGROUND

Chest radiography is often used to detect lung involvement in patients with suspected pneumonia. Chest radiography through glass walls of an isolation room is a technique that could be immensely useful in the current COVID-19 pandemic.

PURPOSE

The purpose of this study was to ensure quality and radiation safety while acquiring portable chest radiographs through the glass doors of isolation rooms using an adult anthropomorphic thorax phantom.

MATERIALS AND METHODS

Sixteen chest radiographs were acquired utilizing different exposure factors without glass, through the smart glass, and through regular glass. Images were scored independently by 2 radiologists for quantum mottle and sharpness of anatomical structures using a 5-point Likert scale. Statistically significant differences in Likert scale scores and entrance surface dose (ESD) between images acquired without glass and through the smart and regular glass were tested. Interreader reliability was also evaluated.

RESULTS

Compared with conventional radiography, equal or higher mean image quality scores (mottle and anatomical structures) were observed with the smart glass using 100 kVp at 12 mAs and 20 mAs and 125 kVp at 6.3 mAs (100 kVp at 2 mAs and 125 kVp at 3.2 mAs were used for conventional radiography observations). There was no statistically significant difference in the Likert scale scores for image quality and the entrance surface dose for radiographs acquired without glass, through the smart glass, and through regular glass. Backscatter from the smart glass was minimal at a distance of 3 m and was recorded as zero at a distance of 4 m from the x-ray tube outside an isolation room.

CONCLUSIONS

Good-quality portable chest radiographs can be obtained safely through the smart glass doors of the isolation room. However, this technique does result in minor backscatter radiation. Modifications in the exposure factors (such as increasing milliampere seconds) may be required to optimize image quality while using this technique.

Portable Chest Radiography Through Glass During COVID-19 Pandemic—Initial Experience in a Tertiary Care Center

Background:

Portable chest radiograph for COVID-19 positive patients and persons under investigation can be acquired through glass doors or walls of isolation rooms to limit exposure to the pathogen and conserve resources.

Purpose:

To report our initial experience with acquiring portable chest radiographs through glass doors of isolation rooms.

Methods:

Only 1 of 2 radiology technologist team members donned personal protective equipment and stayed inside the isolation room, while the second technologist and the radiography unit remained outside during the procedure. First hundred radiographs acquired through glass at the emergency department of our institute formed the “through glass radiograph” group. Hundred consecutive portable chest radiographs performed in a conventional manner formed the “conventional radiograph” group for comparison. Imaging database and feedback from operations leader were used to identify occurrences of a failed procedure. Suggestion of repeating the study and comments related to quality of the study were recorded from the reports of the staff radiologist.

Results:

There was no instance of failed acquisition, nondiagnostic examination, or suggestion of repetition in both groups. No significant difference in the number of reports with quality related remarks ( P > .05) was found between the 2 groups. Radiography through glass doors was associated with increased suboptimal positioning related remarks in radiology reports ( P < .05). No significant association was identified among other comments about image quality.

Conclusion:

Our initial clinical experience suggests that the acquisition of portable chest radiographs through the glass doors of isolation rooms is technically feasible and results in diagnostic quality studies.

MR imaging in the presence of ballistic debris of unknown composition: a review of the literature and practical approach

Due to a combination of increasing indications for MR imaging, increased MRI accessibility, and extensive global armed conflict over the last few decades, an increasing number of patients now and in the future will present with retained metallic ballistic debris of unknown composition. To date, there are no guidelines on how to safely image these patients which may result in patients who would benefit from MRI not receiving it. In this article, we review the current literature pertaining to the MRI safety of retained ballistic materials and present the process we use to safely image these patients.

Clinical significance of posttraumatic intracranial hemorrhage in clinically mild brain injury: a retrospective cohort study

BACKGROUND

Much attention has been focused on management of severe traumatic brain injury (TBI); however, comparatively little is known about management of traumatic hemorrhage in clinically mild TBI. We aimed to clarify the role of clinical observation and repeat radiography for patients with mild TBI and abnormal findings on initial computed tomography (CT) of the head.

METHODS

We queried the neurotrauma database of the Ontario Trauma Registry and the Sunnybrook institutional database to identify patients with CT findings of a traumatic hemorrhage or calvarial fracture between November 2014 and December 2016. Exclusionary criteria were age less than 16 years, Glasgow Coma Scale (GCS) score less than 13, anticoagulant use, bleeding diathesis and midline shift greater than 5 mm. The primary outcome was the need for neurosurgical intervention.

RESULTS

A total of 607 patients were included. Most (374 [61.6%]) had a GCS score of 15; 185 (30.5%) and 48 (7.9%) had a GCS score of 14 and 13, respectively. Five patients (0.8%) required surgical intervention, all within the first 72 hours, owing to clinical deterioration with subsequently demonstrated radiographic evidence of expanding hemorrhage. Most patients (506 [83.4%]) had routine repeat imaging, without documented change in their neurologic status.

INTERPRETATION

The majority of patients in our cohort had repeat imaging, which did not influence surgical management, at substantial cost to the health care system. The findings suggest the need to reevaluate repeat imaging protocols for this subset of patients with TBI.

A case report of caecal herniation through the foramen of Winslow

Caecal herniation through the foramen of Winslow is a rare entity of which radiologist should be aware. We present a case of this entity in a patient presenting with diabetic ketoacidosis and ongoing epigastric pain. Abdominal computed tomography demonstrated herniation of the caecum into the lesser sac via the foramen of Winslow. Despite the caecum appearing viable at the time of surgery, the surgeons performed a right hemicolectomy via laparotomy to prevent future recurrence.

Incidental discovery of a new and clinically important anatomic variant of the internal thoracic artery in a young male trauma patient

The internal thoracic artery (ITA) is the largest thoracic wall artery and is clinically important primarily for use in coronary artery bypass grafting. A number of anatomic variants of the ITA have been reported; however, bilateral, aberrant lateral branches of the ITA never have. The importance of this finding lies in the positioning of the artery at a potential chest tube insertion site. Here, we report the identification, on CT scan, of this rare variation in a young male trauma patient.

Ionizing Radiation Knowledge Among Emergency Department Providers

PURPOSE

The aim of this study was to assess knowledge of ionizing radiation exposure from diagnostic imaging examinations among emergency department (ED) providers.

METHODS

An electronic questionnaire was distributed to ED providers in a five-hospital university-affiliated health care system. Providers included attending emergency medicine (EM) physicians, EM residents, and midlevel providers (MLPs) (nurse practitioners and physicians assistants). Data were collected and analyzed.

RESULTS

One hundred six of 210 providers (41 attending physicians, 32 residents, and 31 MLPs) completed the survey, for a response rate of 50.5%. More than two in five providers (44.6%) could not correctly identify which of six common imaging modalities used ionizing radiation. MLPs were more likely to incorrectly identify radiography (25%) and fluoroscopy (29%) as modalities that did not use ionizing radiation (P = .01 and P = .25 respectively). Fewer attending physicians (14.6%) than residents (37.5%) were not very comfortable or were uncomfortable explaining the risks of radiation to patients. Nearly half of attending physicians (47.5%) and nearly three-quarters of residents (71.9%) were not very comfortable, were uncomfortable, or were extremely uncomfortable explaining the amount of radiation in certain imaging tests to patients. MLPs were more likely to incorrectly rank a selection of imaging tests by radiation exposure (P = .002). MLPs were more likely to incorrectly answer a question on the effects of ionizing radiation on patients (P = .01).

CONCLUSIONS

Among ED providers, there are knowledge gaps regarding the presence and effect of ionizing radiation in diagnostic imaging tests. MLPs were more likely to make factual errors, while EM residents were least comfortable counseling patients about radiation risks.

Images in Clinical Medicine. Spontaneous Retropharyngeal Hematoma

A 56-year-old man presented to the emergency department with a 5-hour history of throat swelling and pain and difficulty breathing that was exacerbated by supine positioning; he had not had any obvious antecedent trauma. His medical history included prostate cancer, hypertension, hyperlipidemia, deep-vein thrombosis, and stroke. Medications included warfarin (presumably for deep-vein thrombosis), antihypertensive agents, and a statin. He was afebrile, and the physical examination was notable for minor swelling of the posterior oropharynx. Laboratory studies revealed a normal white-cell count, an international normalized ratio of more than 11, a prothrombin time of more than 120 seconds, and an activated . . .