Negative Computed Tomography Scan Research Articles

Incidence of intra-abdominal injuries in hemodynamically stable blunt trauma patients with a normal computed tomography scan admitted to the emergency department

ObjectivesBlunt abdominal trauma is a common cause of emergency department admission. Computed tomography (CT) scanning is the gold standard method for identifying intra-abdominal injuries in patients experiencing blunt trauma, especially those with high-energy trauma. Although the diagnostic accuracy of this imaging technique is very high, patient admission and prolonged observation protocols are still common practices worldwide. We aimed to evaluate the incidence of intra-abdominal injury in hemodynamically stable patients with high-energy blunt trauma and a normal abdominal CT scan at a Level-1 Trauma Center in Colombia, South America, to assess the relevance of a prolonged observation period.MethodsWe performed a retrospective study of patients admitted to the emergency department for blunt trauma between 2021 and 2022. All consecutive patients with high-energy mechanisms of trauma and a normal CT scan at admission were included. Our primary outcomes were the incidence of intra-abdominal injury identified during a 24-hour observation period or hospital stay, ICU admission, and death.ResultsWe included 480 patients who met the inclusion criteria. The median age was 33 (IQR 25.5, 47), and 74.2% were male. The most common mechanisms of injury were motor vehicle accidents (64.2%), falls from height (26%), and falls from bikes (3.1%). A total of 99.2% of patients had a Revised Trauma Score of 8. Only 1 patient (0.2%) (95% CI: 0.01–1.16) presented with an abdominal injury during the observation period. No ICU admissions or deaths were reported.ConclusionThe incidence of intra-abdominal injury in patients with hemodynamically stable blunt trauma and a negative abdominal CT scan is extremely low, and prolonged observation may not be justified in these patients.

Acromion and scapular spine fractures after reverse shoulder arthroplasty: rate of detection by computed tomography

BackgroundAcromion and scapular spine fractures (ASFs) after reverse total shoulder arthroplasty have been reported at a rate of 3.9 percent. Radiographs have been shown to be unreliable at identifying these fractures, with an estimated 20% false negative rate. A computed tomography (CT) scan is typically performed when initial radiographs are inconclusive and clinical suspicion for ASF remains high. However, the accuracy of identifying ASF fractures after reverse shoulder arthroplasty (RSA) with CT has not been studied. The purpose of this paper is to evaluate the ability of CT scans to detect clinically suspected ASF fractures after RSA when initial radiographs are inconclusive. MethodsA retrospective review of our institution’s shoulder and elbow repository identified 111 patients treated with RSA from 2006 to 2022 that subsequently sustained an ASF. Upon clinical suspicion of an ASF, a 4-view radiographic series was obtained. If no fracture was clearly identified, a thin-cut CT was obtained. Additional four-view radiographic series were taken at each subsequent follow-up. Rate of detection by CT scan was defined using the number of cases with positive scans out of the number in which both a CT scan was performed, and a fracture was identified on either CT scan or other additional follow-up imaging. ResultsAfter inconclusive radiographs, a CT was ordered for 61 patients (55%) at a median of 1.3 weeks after the onset of signs/symptoms suspicious for ASF. Fractures were identified in 52 cases (85.2%) at a median of 1.6 weeks after the onset of sign/symptoms. The fracture was not seen on CT in 9 cases at a median of 0.9 week after the onset of sign/symptoms, representing a false negative rate of 14.8%. These fractures were later identified on radiographs at a median of 5.9 weeks following the CT scan. No statistical differences were observed in sensitivity of CT scan between fracture types. Fractures initially missed on CT scan eventually displaced and became nonunions. ConclusionCT scans can be helpful in identifying and characterizing ASF following RSA, with an overall rate of detection (sensitivity) of 85%. Consideration of alternative advanced imaging may be needed for patients with negative CT scans and a high index of clinical suspicion for ASF.

A-094 Performance Evaluation of GFAP and UCH-L1 Biomarkers for Traumatic Brain Injury in the Alinity i TBI Test (in development)

Abstract Background Traumatic Brain Injury (TBI) has been recognized as an important cause of death and disability and is a growing public health problem. An estimated 69 million people globally experience a TBI annually. Blood-based biomarkers such as glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase L1 (UCH-L1) have shown utility to predict acute traumatic intracranial injury on head CT scan after TBI. Methods The Alinity i TBI test is a panel of in vitro diagnostic chemiluminescent microparticle immunoassays for the measurement of GFAP and UCH-L1 in plasma and serum. Performance characteristics such as detection limits, imprecision, linearity, measuring interval, expected values, and interferences were established following CLSI guidance. A feasibility cohort of 354 subjects was used to establish cutoffs which assist in determining the need for a CT (computed tomography) scan of the head. A prospective study was conducted to assess the clinical performance of the TBI test. Fresh plasma specimens from 97 mild TBI subjects presenting to Level I trauma centers were collected within 12 h of injury from subjects ≥18 years of age who presented with suspected TBI and had a head CT scan performed. The TBI interpretation is considered positive if either GFAP or UCH-L1 is greater than or equal to the cutoffs. The TBI interpretation is considered negative if both GFAP and UCH-L1 are less than the cutoffs. Results The analytical measuring interval (AMI) extends from the limit of quantitation (LoQ) to the upper LoQ and is determined by the range that demonstrates acceptable performance for linearity, imprecision, and bias. The AMI is 6.1 to 42 000.0 pg/mL for GFAP and 26.3 to 25 000.0 pg/mL for UCH-L1. Within-laboratory imprecision (20 day) ranged from 2.8% to 5.3% CV for GFAP and 2.1% to 5.6% CV for UCH-L1. Cutoffs for GFAP and UCH-L1 of 35.0 pg/mL and 400.0 pg/mL, respectively, were selected using both 10-fold cross validation and bootstrapping methods and applying a selection criterion of negative predictive value (NPV) (prevalence adjusted) ≥99% and Sensitivity ≥96%. Of the 97 mild TBI subjects evaluated, 14 had positive head CT scan results. All 14 of the subjects with positive head CT results had a positive TBI interpretation (Sensitivity 100.0%; 95% CI:78.5%,100.0%). There were 23 subjects with a negative TBI interpretation, all 23 had a negative head CT scan result. The NPV of the test was 100% (95% CI:85.7%,100.0%). Conclusion The Alinity i TBI test shows robust analytical performance across a broad concentration range of GFAP and UCH-L1 and may serve as a valuable tool to help evaluate TBI patients across the spectrum of mild to severe injury. The established cutoffs were evaluated in a prospective cohort of mild TBI (Glasgow Coma Scale score of 13–15) subjects and demonstrated high sensitivity and NPV relative to CT scan results, supporting the utility to rule out the need for CT scan in mild TBI subjects presenting to the emergency department. FUNDING: This work is in collaboration with the US Army Medical Materiel Development Activity, US Army Medical Research and Development Command CRADA 20-1266-CRA.

A-093 Clinical Performance of Biomarkers for Traumatic Brain Injury

Abstract Background An estimated 5 million people are evaluated in emergency departments (ED) for Traumatic Brain Injury (TBI) in the United States each year. The vast majority (80%) of patients evaluated for TBI in the ED will receive head CT scans, however less than 10% of those will have any findings of acute traumatic abnormalities. This highlights the need for objective, rapid, accurate tools to help clinicians evaluate and triage TBI patients and reduce unnecessary radiation exposure. The Alinity i TBI test is a panel of in vitro diagnostic chemiluminescent microparticle immunoassays used to measure glial fibrillary acidic protein (GFAP) and ubiquitin carboxyl-terminal hydrolase L1 (UCH-L1) in human plasma and serum. TBI performance was evaluated in a multi-center study by performing reproducibility and a pivotal study. Methods A pivotal study using prospectively collected archived (frozen) plasma specimens was conducted to establish the clinical performance of the TBI test on the Alinity i system. The testing of the archived specimens was performed at three clinical sites in the United States. The specimens tested were originally collected in a prospective, multi-center clinical study and were from individuals 18 years of age or older who presented to a health care facility or emergency department with suspected traumatic brain injury. These subjects had an initial Glasgow Coma Scale (GCS) score of 13–15 and had a computed tomography (CT) scan of the head performed per the clinical site’s standard of care. Reproducibility was assessed using multiple panel/control members for 5 days based on guidance from Clinical and Laboratory Standards Institute EP05-A3. Testing was conducted using 3 lots of GFAP and UCH-L1 reagents, and 1 Alinity i system at each of 3 testing sites. Results Of the 1899 mild TBI subjects, 120 had positive head CT scan results; 116 of the 120 specimens had a positive TBI interpretation (Sensitivity 96.7%;95%CI:91.7%,98.7%). Of the 1779 subjects with negative CT scan results, 713 had a negative TBI interpretation (Specificity 40.1%;95%CI:37.8%,42.4%). The negative predictive value (NPV) of the test was 99.4% (713/717, 95%CI:98.6%,99.8%). Within-Laboratory imprecision (includes repeatability, between-run, and between-day variance components) results ranged from 2.2% to 3.5% CV for GFAP and 1.8 to 3.2 %CV for UCH-L1. The Overall Reproducibility (includes repeatability, between-run, between-day, between-lot, between-site, and site-lot interaction variance components) results ranged from 2.5% to 4.7% CV for GFAP and 2.6 to 6.6 %CV for UCH-L1. Conclusion The Alinity i TBI clinical performance results demonstrated that the TBI test is characterized by high sensitivity and high NPV, which supports the clinical utility to assist in determining the need for a CT scan of the head in subjects presenting with suspected mild TBI. The GFAP and UCH-L1 assays demonstrated acceptable reproducibility across a wide dynamic range. These assays can report results within 18 min and be conveniently loaded into the Electronic Health Records to aid clinicians in their triage (or imaging) decisions. Funding The study was funded by Abbott Laboratories and in collaboration with the US Army Medical Materiel Development Activity, US Army Medical Research and Development Command CRADA 20-1266-CRA.

Findings on Repeat Posttraumatic Brain Computed Tomography Scans in Older Patients With Minimal Head Trauma and the Impact of Existing Antithrombotic Use.

Evaluate the utility of routine rescanning of older, mild head trauma patients with an initial negative brain computed tomography (CT), who is on a preinjury antithrombotic (AT) agent by assessing the rate of delayed intracranial hemorrhage (dICH), need for surgery, and attributable mortality. Participating centers were trained and provided data collection instruments per institutional review board-approved protocols. Data were obtained from manual chart review and electronic medical record download. Adults ≥55 years seen at Level I/II Trauma Centers, between 2017 and 2019 with suspected head trauma, Glasgow Coma Scale 14 to 15, negative initial brain CT, and no other Abbreviated Injury Scale injuries >2 were identified, grouped by preinjury AT therapy (AT- or AT+) and compared on dICH rate, need for operative neurosurgical intervention, and attributable mortality using univariate analysis (α=.05). A total of 2,950 patients from 24 centers were enrolled; 280 (9.5%) had a repeat brain CT. In those rescanned, the dICH rate was 15/126 (11.9%) for AT- and 6/154 (3.9%) in AT+. Assuming nonrescanned patients did not suffer clinically meaningful dICH, the dICH rate would be 15/2001 (0.7%) for AT- and 6/949 (0.6%) for AT+. No surgical operations were done for dICH. All-cause mortality was 9/2950 (0.3%) and attributable mortality was 1/2950 (0.03%). The attributable death was an AT+, dICH patient whose family declined intervention. In older patients with an initial Glasgow Coma Scale of 14 to 15 and a negative initial brain CT scan, the dICH rate is low (<1%) and of minimal clinical consequence, regardless of AT use. In addition, no patient had operative neurosurgical intervention. Therefore, routine rescanning is not supported based on the results of this study.

Development and External Validation of a Deep Learning Algorithm to Identify and Localize Subarachnoid Hemorrhage on CT Scans.

In medical imaging, a limited number of trained deep learning algorithms have been externally validated and released publicly. We hypothesized that a deep learning algorithm can be trained to identify and localize subarachnoid hemorrhage (SAH) on head computed tomography (CT) scans and that the trained model performs satisfactorily when tested using external and real-world data. We used noncontrast head CT images of patients admitted to Helsinki University Hospital between 2012 and 2017. We manually segmented (i.e., delineated) SAH on 90 head CT scans and used the segmented CT scans together with 22 negative (no SAH) control CT scans in training an open-source convolutional neural network (U-Net) to identify and localize SAH. We then tested the performance of the trained algorithm by using external data sets (137 SAH and 1,242 control cases) collected in 2 foreign countries and also by creating a data set of consecutive emergency head CT scans (8 SAH and 511 control cases) performed during on-call hours in 5 different domestic hospitals in September 2021. We assessed the algorithm's capability to identify SAH by calculating patient- and slice-level performance metrics, such as sensitivity and specificity. In the external validation set of 1,379 cases, the algorithm identified 136 of 137 SAH cases correctly (sensitivity 99.3% and specificity 63.2%). Of the 49,064 axial head CT slices, the algorithm identified and localized SAH in 1845 of 2,110 slices with SAH (sensitivity 87.4% and specificity 95.3%). Of 519 consecutive emergency head CT scans imaged in September 2021, the algorithm identified all 8 SAH cases correctly (sensitivity 100.0% and specificity 75.3%). The slice-level (27,167 axial slices in total) sensitivity and specificity were 87.3% and 98.8%, respectively, as the algorithm identified and localized SAH in 58 of 77 slices with SAH. The performance of the algorithm can be tested on through a web service. We show that the shared algorithm identifies SAH cases with a high sensitivity and that the slice-level specificity is high. In addition to openly sharing a high-performing deep learning algorithm, our work presents infrequently used approaches in designing, training, testing, and reporting deep learning algorithms developed for medical imaging diagnostics. This study provides Class III evidence that a deep learning algorithm correctly identifies the presence of subarachnoid hemorrhage on CT scan.

Meta-Analysis on Utility of Bronchoscopy in Addition to Computed Tomography Thorax in the Investigation of Lung Cancer in Patients with Haemoptysis

Background: In patients with haemoptysis, many healthcare systems support bronchoscopy regardless of computed tomography (CT) findings. Objective: This meta-analysis aimed to address whether a normal CT alone is sufficient to out-rule lung cancer in patients with haemoptysis. Methods: A search was performed of the following databases: EBSCO (Medline), PubMed, Academic Search Complete, CINAHL, Cochrane Library, and Embase. Meta-Disc 1.4 and RevMan software were used to test for heterogeneity, risk of bias, and to summarize the test performance characteristics using forest plots and summary receiver operating characteristic (SROC) curves. SPSS was used to compare the diagnostic accuracy of CT and bronchoscopy. Results: A total of 14 studies (2,960 patients) were included. The pooled sensitivities for detection of lung cancer using CT scan and bronchoscopy were 0.99 (95% CI: 0.97–1.00) and 0.84 (95% CI: 0.78–0.88), respectively. The sensitivity of CT was higher than that of bronchoscopy (p < 0.001). The pooled specificities for CT scan and bronchoscopy were 0.99 (95% CI: 0.99–1.00) and 1.00 (95% CI: 0.99–1.00), respectively. Of 2,960 patients, 257 had lung cancer (8.7%) at initial investigation. 254 of these had a CT thorax, and the CT scan was false negative in 4/255 (1.6%), with bronchoscopy only identifying one cancer with a normal CT (0.4%). Conclusion: CT scan showed a higher diagnostic accuracy than bronchoscopy. This study indicated that bronchoscopy offers an insignificant additional value in the investigation of lung cancer in patients with haemoptysis and a negative CT scan.

Temporary or Permanent? A Clinical Challenge in the Evaluation of Traumatic Brain Injury Patients with Unconsciousness and Normal Initial Head CT.

Traumatic brain injury (TBI) patients with unconsciousness and normal initial head computed tomography (CT) present a clinical dilemma for physicians and neurosurgeons in the emergency department (ED). We recorded how long it took for patients to regain consciousness and evaluated the patients' characteristics. From 2018 to 2020, TBI patients with unconsciousness and normal initial head CT [Glasgow coma scale (GCS) score < 13, negative CT scan and normal laboratory test results] were evaluated. Patients who regained consciousness were analyzed. Multivariate logistic regression (MLR) analyses were used to evaluate independent factors for regaining consciousness. A total of 77 patients were included in this study. Fifty-eight (75.3%) patients regained consciousness, most within one day (43.1%). Nineteen (24.7%) patients never regained consciousness. MLR analysis showed that initial GCS score (odds 1.85, p = 0.017), early airway protection in ED (odds 25.02, p = 0.018) and 72-h GCS score improvement by two points (odds 0.02, p = 0.001) were independent factors for regaining consciousness. Overall, 94.1% of patients who received early airway protection and improved 2 points in 72-h GCS score regained consciousness. The association between days to M5 status and days to M6 status (consciousness) was highly significant. Fewer days to M5 status were highly associated with needing fewer days to regain consciousness. For TBI patients with unconsciousness and normal initial head CT, a higher probability of regaining consciousness was observed in those who underwent early airway protection and who improved 2 points in 72-h GCS score. Regaining consciousness within a short period could be expected in patients with M5 status.

Outcomes in Patients With Mild Traumatic Brain Injury Without Acute Intracranial Traumatic Injury

Traumatic brain injury (TBI) affects millions of people in the US each year. Most patients with TBI seen in emergency departments (EDs) have a Glasgow Coma Scale (GCS) score of 15 and a head computed tomography (CT) scan showing no acute intracranial traumatic injury (negative head CT scan), yet the short-term and long-term functional outcomes of this subset of patients remain unclear. To describe the 2-week and 6-month recovery outcomes in a cohort of patients with mild TBI with a GCS score of 15 and a negative head CT scan. This cohort study analyzed participants who were enrolled from January 1, 2014, to December 31, 2018, in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study, a prospective, observational cohort study of patients with TBI that was conducted in EDs of 18 level I trauma centers in urban areas. Of the total 2697 participants in the TRACK-TBI study, 991 had a GCS score of 15 and negative head CT scan and were eligible for inclusion in this analysis. Data were analyzed from September 1, 2021, to May 30, 2022. The primary outcome was the Glasgow Outcome Scale-Extended (GOS-E) score, which was stratified according to functional recovery (GOS-E score, 8) vs incomplete recovery (GOS-E score, <8), at 2 weeks and 6 months after the injury. The secondary outcome was severity of mild TBI-related symptoms assessed by the Rivermead Post Concussion Symptoms Questionnaire (RPQ) total score. A total of 991 participants (mean [SD] age, 38.5 [15.8] years; 631 male individuals [64%]) were included. Of these participants, 751 (76%) were followed up at 2 weeks after the injury: 204 (27%) had a GOS-E score of 8 (functional recovery), and 547 (73%) had a GOS-E scores less than 8 (incomplete recovery). Of 659 participants (66%) followed up at 6 months after the injury, 287 (44%) had functional recovery and 372 (56%) had incomplete recovery. Most participants with incomplete recovery reported that they had not returned to baseline or preinjury life (88% [479 of 546]; 95% CI, 85%-90%). Mean RPQ score was 16 (95% CI, 14-18; P < .001) points lower at 2 weeks (7 vs 23) and 18 (95% CI, 16-20; P < .001) points lower at 6 months (4 vs 22) in participants with a GOS-E score of 8 compared with those with a GOS-E score less than 8. This study found that most participants with a GCS score of 15 and negative head CT scan reported incomplete recovery at 2 weeks and 6 months after their injury. The findings suggest that emergency department clinicians should recommend 2-week follow-up visits for these patients to identify those with incomplete recovery and to facilitate their rehabilitation.

Excluding Hollow Viscus Injury for Abdominal Seat Belt Sign Using Computed Tomography

Abdominal seat belt sign (SBS) has historically entailed admission and observation because of the diagnostic limitations of computed tomography (CT) imaging and high rates of hollow viscus injury (HVI). Recent single-institution, observational studies have questioned the utility of this practice. To evaluate whether a negative CT scan can safely predict the absence of HVI in the setting of an abdominal SBS. This prospective, observational cohort study was conducted in 9 level I trauma centers between August 2020 and October 2021 and included adult trauma patients with abdominal SBS. Inclusion in the study required abdominal CT as part of the initial trauma evaluation and before any surgical intervention, if performed. Results of CT scans were considered positive if they revealed any of the following: abdominal wall soft tissue contusion, free fluid, bowel wall thickening, mesenteric stranding, mesenteric hematoma, bowel dilation, pneumatosis, or pneumoperitoneum. Presence of HVI diagnosed at the time of operative intervention. A total of 754 patients with abdominal SBS had an HVI prevalence of 9.2% (n = 69), with only 1 patient with HVI (0.1%) having a negative CT (ie, none of the 8 a priori CT findings). On bivariate analysis comparing patients with and without HVI, there were significant associations between each of the individual CT scan findings and the presence of HVI. The strongest association was found with the presence of free fluid, with a more than 40-fold increase in the likelihood of HVI (odds ratio [OR], 42.68; 95% CI, 20.48-88.94; P < .001). The presence of free fluid also served as the most effective binary classifier for presence of HVI (area under the receiver operator characteristic curve [AUC], 0.87; 95% CI, 0.83-0.91). There was also an association between a negative CT scan and the absence of HVI (OR, 41.09; 95% CI, 9.01-727.69; P < .001; AUC, 0.68; 95% CI, 0.66-0.70). The prevalence of HVI among patients with an abdominal SBS and negative findings on CT is extremely low, if not zero. The practice of admitting and observing all patients with abdominal SBS should be reconsidered when a high-quality CT scan is negative, which may lead to significant resource and cost savings.

Hemifacial spasm is not affected by state of consciousness: a case report

Background Hemifacial spasm (HFS) is a movement disorder caused by mechanical compression of the facial nerve after it has left the brainstem and is characterized by brief or sustained twitching of the muscles innervated by that nerve. Often we observe spasm in an awakening situation. Actually contractions persist during sleep. To our knowledge, there were no reports on how HFS manifests under disturbance of consciousness. Here, we report a case of primary HFS in which the patient's symptoms persisted in a coma.Case presentationA 74-year-old female with right-sided primary HFS for 20 years and had received botulinum toxin injections in our hospital. Unfortunately she was carried to emergency department after traumatic right pneumothorax by accident. During the emergency treatment, she lost consciousness due to simultaneous cardiac arrest and respiratory arrest. She was then admitted to the emergency intensive care unit for further treatment. During her hospitalization, she was in a coma with stable vital signs and persisting symptoms of HFS. Thus, a multidisciplinary consultation was requested to identify whether it was focal cortical seizures involving the right-side facial muscles. Physical examination revealed brief involuntary clonic or tonic contractions accompanied with the ‘Babinski-2 sign’. A combination of relevant data, including her past history, clinical presentation and a negative computed tomography scan of the head, led to a diagnosis of right-sided HFS. As the symptoms of HFS are not life-threatening, the use of anticonvulsants is unnecessary.ConclusionsFor the layperson, it is crucial to seek a multidisciplinary consultation to obtain a correct diagnosis.

Анализ симптоматики и функционального исхода легкой черепно-мозговой травмы

The consequences of TBI are most often grouped into the so-called Post-concussion Syndrome (PCS). At present, there is no clear understanding of the evolution, duration, or resolution of the symptoms of PCS after mild traumatic brain injury (mTBI). Aim of the study. A prospective characterization of the frequency and evolution of PCS symptoms and outcomes of patients after mTBI for 3, 6, and 12 months in a large prospective cohort of patients in the emergency department. Material and methods. A total of 375 patients met the inclusion criteria. Patients were evaluated using the PCS checklist, as well as the Extended Glasgow Outcome Scale (EGOS), the Short List of Symptoms-18 (SLS-18), the Rivermead Post-Concussion Questionnaire (RPCQ), and the Life Satisfaction Scale (LSS). Results. The population was 70.1% male, with a median age of 44 years. Approximately 44% of the population were considered to have complicated mTBI, having positive results of computed tomography (CT). The average injury severity score (ISS), calculated only for patients admitted to the hospital, was 9.37±9.72 (279 in total). ISS was significantly higher in patients with positive CT (16.5±8.39) compared to patients with negative CT (3.8±6.6). Conclusion. Patients with negative CT scans had significantly increased rates of neurological problems, prior TBI, and alcohol use, which may contribute to increased symptoms and a deterioration in BSI-18 scores. After examining only those patients with a negative history of the disease, there was no significant difference between the groups with positive and negative results for any indicator of outcome.

The utility of a second head CT scan after a negative initial CT scan in head trauma patients on new direct oral anticoagulants (DOACs)

BackgroundNew direct oral anticoagulants (DOACs) are commonly used in the management of atrial fibrillation and VTE. Currently, there is no strong evidence to support the current practice of routinely repeating computed tomography (CT) head in anticoagulated patients within 24 hours after their first negative CT scan to assess for new and delayed intracranial hemorrhage (ICH). Our hypothesis is that the vast majority will not have new CT scan findings of ICH and those who do would not require any further intervention. MethodsThis is retrospective cohort study. IRB approval was obtained. Subjects included adults age ≥ 18 taking DOACs who presented to our level III trauma center with confirmed or suspected blunt head trauma between August 2013 and October 2019 and received at least one head CT scans. Results498 Patient encounters met inclusion criteria. Only 19 patients (3.8%) had positive traumatic ICH on the initial CT head. Those had a higher ISS. 420 out of 479 initial negative CT encounters received a second CT head. Only 2 (0.5%) had delayed positive second CT scan for ICH. 95%CI [0.06%, 1.7%] Patients who developed a new ICH on the second CT head after an initial negative CT scan had a lower Glasgow Coma Scale (GCS) on presentation and a higher ISS. None of those patients required neurosurgical intervention ConclusionOur data suggests that the risk of developing a new or delayed traumatic ICH for patients on DOAC on a second CT head within 24 hours following an initial negative CT is very low and when present did not require neurosurgical intervention and thus does not support routinely obtaining a repeat CT head within 24 hours after a negative initial CT scan. Patients presenting with lower GCS and higher ISS had a higher chance of having a delayed ICH.

Lumbar Puncture Should Not Be Routinely Performed For Subarachnoid Hemorrhage After A Negative Head Ct

Headache is a common presenting complaint in the emergency department (ED), and approximately 1% of patients with a sudden-onset headache receive a diagnosis of subarachnoid hemorrhage.1 Historically, it has been taught that a lumbar puncture is required after a negative computed tomographic (CT) result to exclude the diagnosis. However, in light of improving CT quality, the value of this approach has been questioned. In accordance with the current evidence, we argue that lumbar puncture is not routinely required to rule out subarachnoid hemorrhage after a negative head CT scan result, even if the CT was performed more than 6 hours after symptom onset.

Trust the FAST: Confirmation that the FAST examination is highly specific for intra-abdominal hemorrhage in over 1,200 patients with pelvic fractures.

Use of the focused assessment with sonography for trauma (FAST) examination in patients with pelvic fractures has been reported as unreliable. We hypothesized that FAST is a reliable method for detecting clinically significant intra-abdominal hemorrhage in patients with pelvic fractures. All patients with pelvic fractures over a 10-year period were reviewed at a Level I trauma center. The predictive ability of FAST was assessed by calculating the sensitivity, specificity, positive predictive value and negative predictive value against the criterion standard of either computed tomography (CT) or laparotomy findings. The FAST examination was considered "false negative" if findings at laparotomy indicated traumatic intra-abdominal hemorrhage. Likewise, the FAST examination was considered "false positive" if either CT or findings at laparotomy indicated no intra-abdominal hemorrhage. Hemodynamic instability scores were calculated for all patients. There were 1,456 patients with pelvic fractures and an initial FAST reviewed; 1,219 (83.7%) underwent FAST and either CT or operative exploration. Median age was 43 years (interquartile range, 26-56 years) and mean Injury Severity Score was 18.5 ± 12.3. The sensitivity and specificity for FAST in this group of patients with pelvic fracture was 85.4% and 98.1%, respectively. The positive predictive value and negative predictive value were 78.4% and 98.8%, respectively. Of 21 patients with a false-positive FAST, 15 (71.4%) were confirmed with a negative CT scan, and 6 (28.6%) underwent laparotomy without findings of intra-abdominal hemorrhage. Of 13 patients with a false-negative FAST, all were identified with positive findings at the time of laparotomy. The specificity of the FAST examination remained high regardless of hemodynamic instability score grade. The false positive rate of FAST examination for intra-abdominal hemorrhage is 1.1%. These data suggest that a positive FAST in this clinical scenario should be considered to represent intra-abdominal fluid. This series contradicts prior reports that FAST is unreliable in patients with pelvic fracture. Diagnostic, level III.

The value of CT imaging and CRP quotient for detection of postbariatric complications

BackgroundThe diagnosis of major complications seems to be more challenging in obese patients. We aimed to show the relevance of routinely assessed clinical and paraclinical parameters as well as the relevance of CT scans in the diagnosis of major complications after bariatric procedures.MethodsAll patients who underwent operations (primary or revisional) in a 3-year period were retrospectively studied after bariatric surgery with a specific focus on the routinely assessed clinical parameters (tachycardia, temperature), paraclinical parameters on postoperative day (POD) 1 and 3 (C-reactive protein (CRP), leukocytes), and additional computed tomography (CT) scan results for the diagnosis of leakage, bleeding, intraabdominal abscess, superficial abscess, and other complications.ResultsA total of 587 patients were examined. In this cohort, 73 CT scans were performed due to suspected intraabdominal or pulmonary complication according to our hospital standard operating procedure. In total, 14 patients (2.4%) had a major complication (Clavien-Dindo grade IV/V). Of those, 10 patients (1.7%) had postoperative leakage. While the correct leakage diagnosis was only found in 33% of the patients by CT scan, the overall specificity of CT as a diagnostic tool for all kinds of complications remained high. Especially for abscess detection, CT scan showed a sensitivity and specificity of 100%. Multivariate analysis showed a significantly higher risk of leakage development characterized by a doubling of postoperative CRP level (odds ratio 4.84 (95% confidence interval 2.01–11.66, p < 0.001)). To simplify the use of CRP as a predictive factor for the diagnosis of leakage, a cut-off value of 2.4 was determined for the CRP quotient (POD3/POD1) with a sensitivity of 0.88 and a specificity of 0.89.ConclusionCT diagnostic after bariatric surgery has a high positive predictive value, especially for intraabdominal abscess formation. Nevertheless, CT scan for the diagnosis of leakage has a low sensitivity. Thus, a negative CT scan does not exclude the presence of a leakage. Using the described CRP quotient with a cut-off of 2.4, the risk of early leakage can be easily estimated. Furthermore, in any uncertain case of clinically suspected leakage, diagnostic laparoscopy should be performed.

Utility of lumbar puncture after a normal brain computed tomography scan in patients presenting to the emergency department with suspected subarachnoid haemorrhage: A new more rational approach?

The diagnostic approach for patients presenting to EDs with headaches suspicious for subarachnoid haemorrhage (SAH) remains challenging. Modern third-generation computed tomography (CT) has been shown to be extremely sensitive in identifying SAH and may eliminate the need for lumbar puncture (LP) which is an invasive, time-consuming procedure with limited accuracy and complications. The aim of this study is to assess the utility of LP in patients being evaluated for possible SAH in the ED after a negative non-contrast CT scan of the brain, as well as addressing the knowledge gap in regard to rational diagnostics among clinicians. We conducted a retrospective data analysis of patients being evaluated for possible SAH between June 2013 and June 2018 across three EDs in Victoria, Australia. A diagnosis of SAH was defined by SAH on CT or an abnormal cerebrospinal fluid result in conjunction with positive results on cerebral angiography. A follow-up period of 6 months was chosen. A total of 4407 patients met inclusion criteria; 397 (9%) patients were diagnosed with SAH on CT. A total of 388 patients underwent LP and 778 were admitted to hospital for further investigations and management. A total of 2613 patients discharged from ED without LP remained well at 6 months from their initial presentation, but 230 cases were lost to follow up. One patient died from haemorrhagic stroke during his third hospitalisation. A single patient demonstrated a true positive LP after a normal CT brain. LP is not required in all patients with suspected SAH who have a negative CT scan. There are defining patient characteristics that can be used to risk stratify patients and may eliminate the need for LP.

Diagnosis of SARS-CoV-2 infection based on CT scan vs RT-PCR: reflecting on experience from MERS-CoV

Diagnosis of SARS-CoV-2 infection based on CT scan vs RT-PCR: reflecting on experience from MERS-CoV

CT scan is more accurate in predicting viable disease after microwave ablation then tace in patients undergoing locoregional treatment in hepatocellular carcinoma

Presenter: Maria Baimas-George MD, MPH | Carolinas HealthCare System Background: The use of locoregional therapies such as laparoscopic tumor ablation or intra-arterial chemotherapy in hepatocellular carcinoma (HCC) to achieve local control, reduce transplant list dropout, downstage, or reduce recurrence is common practice. Assessing tumor response after treatment, however, remains difficult and unreliable without an explant specimen. We sought to determine the accuracy of imaging in treatment success after locoregional therapy in HCC. Methods: Patients with HCC who underwent either microwave ablation (MWA) and/or transarterial chemoembolization (TACE) prior to hepatectomy or transplantation were retrospectively identified from 2008 to 2018. Computed tomography (CT) scans after treatment and prior to resection were evaluated for characteristics consistent with viable tumor. The explant specimen was identified, and tumor response was assessed through pathologic evaluation. The accuracy of the pre-operative CT scan readings was compared with the pathologic findings of the explant specimen. Results: Ninety-one patients were identified who underwent locoregional treatment prior to resection or transplant. Of these, 14 patients underwent laparoscopic MWA, 46 underwent TACE, and 31 underwent both treatments in a neoadjuvant fashion. The ability of CT imaging to predict tumor viability was assessed by treatment modality. For MWA, CT scans demonstrated a 75% positive predictive value (PPV) and a 67% negative predictive value (NPV). This correlated with a 50% sensitivity and 86% specificity. For TACE, CT scans demonstrated an 87% positive predictive value (PPV) and a 25% negative predictive value (NPV). This correlated with an 82% sensitivity and 33% specificity. For MWA-TACE, CT scans demonstrated an 80% positive predictive value (PPV) and a 39% negative predictive value (NPV). This correlated with a 42% sensitivity and 78% specificity. Conclusion: Imaging to guide response to locoregional therapies in HCC has variable accuracy. There is a high probability of finding tumor given a positive CT scan after all three treatment modalities, whereas a negative CT scan is unreliable. Specifically, CT imaging after MWA demonstrates a high specificity and will likely rule out any residual tumor and CT imaging after TACE is highly sensitive and will likely find residual tumor.

The use of computed tomography imaging for abdominal seatbelt sign: A single-center, prospective evaluation

IntroductionGuidelines surrounding abdominal seat belt sign (SBS) were made prior to the use of modern computed tomography (CT) imaging. We sought to prospectively determine whether a negative CT scan is associated with the absence of hollow viscus injury (HVI), and we hypothesized that trauma patients with an abdominal SBS without CT imaging findings would not have a hollow viscus injury (HVI). MethodsA prospective cohort of patients with SBS was compiled over one year. Subjects were divided into those with and without HVI. Covariate distributions were summarized by group. Bivariate tests and logistic regression were used to investigate associations between covariates and HVI. ResultsOf 220 patients with SBS, the incidence of HVI was 7% (n = 15). Radiographic findings were strongly associated with HVI and no patients with a negative CT scan had HVI. Free fluid was seen in 80% (12) of patients with HVI, whereas it was found in only 11% (23) without injury. A composite variable for negative CT scan was found to be associated with the absence of HVI: (Fisher's exact 1-tailed p, doubled = 0.014). ConclusionIn this study, the incidence of HVI with SBS is lower than previously reported, and no patients with negative CT imaging required an operation for HVI—suggesting there is a population of patients with SBS who could be discharged from the emergency room. A prospective multicenter study is needed to confirm these findings.