Underwent Head Computed Tomography Research Articles

Clinical Differences between Radiographic and Physical Horizontal Gaze Deviation: Utility of Using the Two in Patients with Ischemic Stroke

Background and Purpose Radiographic horizontal gaze deviation (RHGD) has been identified as a useful finding on computed tomography (CT) that indicates the affected side in supratentorial ischemic stroke; however, it remains unclear whether RHGD is essentially the same phenomenon as physical horizontal gaze deviation (PHGD). To resolve the issue, this study was conducted. Methods Retrospective analyses were performed for 671 patients with ischemic stroke and 142 controls who were hospitalized and underwent head CT. First, clinical findings were examined to find differences between RHGD-positive and RHGD-negative patients. Second, patients were classified by their stroke mechanisms and/or affected vascular territories. For each subgroup, RHGD was compared with PHGD in frequency. Third, the proportions for patients divided by positivity for PHGD and RHGD were calculated in the subgroups. Results Patients with RHGD had PHGD more often than those without. In all stroke subgroups, RHGD was more frequent than PHGD. The frequency difference was prominent in small-artery occlusion (SAO) and posterior inferior cerebellar artery (PICA) stroke. In SAO of the basilar artery pontine perforator, RHGD was positive in 25% and largely contralesionally-directed. In PICA stroke, lesions in the vestibulocerebellum were associated with contralesional RHGD. Moreover, lesions in the lateral medulla also caused RHGD, which was mainly directed to the ipsilesional side. PHGD-positive stroke without RHGD was infrequent, whereas RHGD-positive stroke without PHGD was commonly observed (PICA stroke, 45.9%; other subgroups, 21.1%-27.5%). Conclusions RHGD had different characteristics from PHGD; therefore, assessments of both PHGD and RHGD may lead to more accurate diagnoses.

Incidence of surgically treated chronic subdural hematoma after head injury with normal initial computed tomography

PurposeThe objective was to determine the incidence of surgically treated chronic subdural hematoma (cSDH) within six months after head trauma in a consecutive series of head injury patients with a normal initial computed tomography (CT).MethodsA total of 1941 adult patients with head injuries who underwent head CT within 48 h after injury and were treated at the Tampere University Hospital’s emergency department were retrospectively evaluated from medical records (median age = 59 years, IQR = 39–79 years, males = 58%, patients using antithrombotic medication = 26%). Patients with no signs of acute traumatic intracranial pathology or any type of subdural collection on initial head CT were regarded as CT negative (n = 1573, 81%).ResultsTwo (n = 2) of the 1573 CT negative patients received surgical treatment for cSDH. Consequently, the incidence of surgically treated cSDH after a normal initial head CT during a six-month follow-up was 0.13%. Both patients sustained mild traumatic brain injuries initially. One of the two patients was on antithrombotic medication (warfarin) at the time of trauma, hence incidence of surgically treated cSDH among patients with antithrombotic medication in CT negative patients (n = 376, 23.9%) was 0.27%. Additionally, within CT negative patients, one subdural hygroma was operated shortly after trauma.ConclusionThe extremely low incidence of surgically treated cSDH after a normal initial head CT, even in patients on antithrombotic medication, supports the notion that routine follow-up imaging after an initial normal head CT is not indicated to exclude the development of cSDH. Additionally, our findings support the concept of cSDH not being a purely head trauma-related disease.

Association Between Head Computed Tomography Findings and In-Hospital Mortality in COVID-19 Patients.

The present study investigated the association between head computed tomography (CT) findings and mortality in patients with COVID-19. Specifically, we focused on low-density lesions identified on head CT screenings. We performed a single-center, retrospective cohort study based on data obtained from the medical charts of inpatients admitted to the Tokyo Metropolitan Hiroo Hospital between January 1 and December 31, 2021. We focused on the basal ganglia--a representative anatomical region for assessing routine head CT in patients with COVID-19. Patients were divided into two groups based on the presence or absence of low-density lesions in the basal ganglia. The primary outcome was all-cause in-hospital mortality, and the secondary outcome was the length of hospital stay. We performed multivariable regression analyses for outcomes to adjust for patients' background and disease severity. During the study period, 1,906 COVID-19 patients were admitted to our facility. Among them, 1,203 patients underwent head CT evaluations and were included in this study. The median age was 56 years (interquartile range: 43-76 years) and 725 patients (60.3%) were male. A total of 235 (19.5%) patients required oxygen therapy on admission and 1,051 (87.4%) patients had pneumonia. Crude in-hospital mortality was 6.1% and the median length of hospital stay was 10 days (interquartile range: 8-14 days). The multivariate regression analyses showed that low-density lesions in the basal ganglia were significantly associated with increased in-hospital mortality and prolonged hospital stay. The presence of ischemic changes in the basal ganglia denoted by low-density findings may be a promising prognostic factor in patients with COVID-19.

Impact of cerebral small vessel disease burden and drug level at admission on direct oral anticoagulant associated intracerebral hemorrhage.

Direct oral anticoagulant (DOAC)-associated intracerebral hemorrhage (ICH) is a catastrophic complication. The aim of this study was to investigate the association between computed tomography (CT)-based cerebrovascular small vessel disease (SVD) burden and DOAC-ICH as well as the DOAC concentration upon hospital admission and ICH outcome. The study included two cohorts: (1) DOAC-ICH: patients who suffered from DOAC-ICH and underwent drug level measurements upon admission; (2) DOAC-non-ICH: stable DOAC users who underwent head CT without ICH during treatment. We categorized the DOAC levels of the DOAC-ICH patients as low (<50 ng/mL), medium (50-300 ng/mL), and high (>300 ng/mL). The CT-based SVD burden (including white matter lesions [WML], lacunes, and cerebral atrophy) was evaluated, and SVD scores (range, 0-3) were used to evaluate SVD severity. A total of 43 DOAC-ICH patients and 177 DOAC-non-ICH patients were enrolled. DOAC-ICH patients were more likely to have WML, lacunes, or cerebral atrophy compared to DOAC-non-ICH patients. After adjustment, the SVD burden was associated with DOAC-ICH, with a higher risk of more severe SVD (SVD score of 2; odds ratio [OR], 10.3 [3.17, 33.3]; score of 3; OR, 16.8 [4.50, 62.6]). The proportions of patients with high, medium, and low drug levels in the DOAC-ICH group were 16.3%, 55.8%, and 27.9%, respectively. Additionally, the high-level group displayed a larger hematoma size and had worse functional outcomes at 3 months than the other two groups. The severity of SVD burden was associated with DOAC-ICH. Furthermore, high DOAC levels in ICH were associated with unfavorable clinical outcomes. To address the potential selection bias from these two cohorts, a prospective study to investigate the co-contribution of drug levels and SVD to DOAC-ICH is essential.

Tandem cranial and spinal cerebrospinal fluid leaks presenting with otogenic tension pneumocephalus: illustrative case.

Cranial and spinal cerebrospinal fluid (CSF) leaks are associated with opposite CSF fluid dynamics. The differing pathophysiology between spontaneous cranial and spinal CSF leaks are, therefore, mutually exclusive in theory. A 66-year-old female presented with tension pneumocephalus. The patient underwent computed tomography (CT) scanning, which demonstrated left-sided tension pneumocephalus, with an expanding volume of air directly above a bony defect of the tegmen tympani and mastoideum. The patient underwent a left middle fossa craniotomy for repair of the tegmen CSF leak. In the week after discharge, she developed a recurrence of positional headaches and underwent head CT. Further magnetic resonance imaging of the brain and thoracic spine showed bilateral subdural hematomas and multiple meningeal diverticula. Cranial CSF leaks are caused by intracranial hypertension and are not associated with subdural hematomas. Clinicians should maintain a high index of suspicion for intracranial hypotension due to spinal CSF leak whenever "otogenic" pneumocephalus is found. Close postoperative follow-up and clinical monitoring for symptoms of intracranial hypotension in any patients who undergo repair of a tegmen defect for otogenic pneumocephalus is recommended.

Development of a Deep Learning Model for Retinal Hemorrhage Detection on Head Computed Tomography in Young Children

Abusive head trauma (AHT) in children is often missed in medical encounters, and retinal hemorrhage (RH) is considered strong evidence for AHT. Although head computed tomography (CT) is obtained routinely, all but exceptionally large RHs are undetectable on CT images in children. To examine whether deep learning-based image analysis can detect RH on pediatric head CT. This diagnostic study included 301 patients diagnosed with AHT who underwent head CT and dilated fundoscopic examinations at a quaternary care children's hospital. The study assessed a deep learning model using axial slices from 218 segmented globes with RH and 384 globes without RH between May 1, 2007, and March 31, 2021. Two additional light gradient boosting machine (GBM) models were assessed: one that used demographic characteristics and common brain findings in AHT and another that combined the deep learning model's risk prediction plus the same demographic characteristics and brain findings. Sensitivity (recall), specificity, precision, accuracy, F1 score, and area under the curve (AUC) for each model predicting the presence or absence of RH in globes were assessed. Globe regions that influenced the deep learning model predictions were visualized in saliency maps. The contributions of demographic and standard CT features were assessed by Shapley additive explanation. The final study population included 301 patients (187 [62.1%] male; median [range] age, 4.6 [0.1-35.8] months). A total of 120 patients (39.9%) had RH on fundoscopic examinations. The deep learning model performed as follows: sensitivity, 79.6%; specificity, 79.2%; positive predictive value (precision), 68.6%; negative predictive value, 87.1%; accuracy, 79.3%; F1 score, 73.7%; and AUC, 0.83 (95% CI, 0.75-0.91). The AUCs were 0.80 (95% CI, 0.69-0.91) for the general light GBM model and 0.86 (95% CI, 0.79-0.93) for the combined light GBM model. Sensitivities of all models were similar, whereas the specificities of the deep learning and combined light GBM models were higher than those of the light GBM model. The findings of this diagnostic study indicate that a deep learning-based image analysis of globes on pediatric head CTs can predict the presence of RH. After prospective external validation, a deep learning model incorporated into CT image analysis software could calibrate clinical suspicion for AHT and provide decision support for which patients urgently need fundoscopic examinations.

Time ratio disparities among ED patients undergoing head CT.

To assess if patients who underwent head computed tomography (CT) experienced disparities in the emergency department (ED) and if the indication for head CT affected disparities. This study employed a retrospective, IRB-approved cohort design encompassing four hospitals. All ED patients between January 2016 and September 2020 who underwent non-contrast head CTs were included. Furthermore, key time intervals including ED length of stay (LOS), ED assessment time, image acquisition time, and image interpretation time were calculated. Time ratio (TR) was used to compare these time intervals between the groups. A total of 45,177 ED visits comprising 4730 trauma cases, 5475 altered mental status cases, 11,925 cases with head pain, and 23,047 cases with other indications were included. Females had significantly longer ED LOS, ED assessment time, and image acquisition time (TR = 1.012, 1.051, 1.018, respectively, P-value < 0.05). This disparity was more pronounced in female patients with head pain complaints compared to their male counterparts (TR = 1.036, 1.059, and 1.047, respectively, P-value < 0.05). Black patients experienced significantly longer ED LOS, image acquisition time, and image assessment time (TR = 1.226, 1.349, and 1.190, respectively, P-value < 0.05). These disparities persisted regardless of head CT indications. Furthermore, patients with Medicare/Medicaid insurance also faced longer wait times in all the time intervals (TR > 1, P-value < 0.001). Wait times for ED head CT completion were longer for Black patients and Medicaid/Medicare insurance holders. Additionally, females experienced extended wait times, particularly when presented with head pain complaints. Our findings underscore the importance of exploring and addressing the contributing factors to ensure equitable and timely access to imaging services in the ED.

Prevalence of Stroke in Patient Presenting to Emergency Department (ED) With Dizziness Base on Brain Computed Tomography (CT)

Objectives: Dizziness is a common acute emergency complain which can present in isolation. Diagnosing a stroke in patient complains of dizziness only is major challenge to the practicing emergency physician as this symptom nor sensitive neither specific. The purpose of this study was to measure the prevalence of stroke as a diagnosis in patient who present to the emergency department with dizziness base on brain CT. Methods: This is Retrospective, Cross sectional study was carried out at the Armed Force Hospital (adult ED) in Muscat, Oman, from between August 2019 -August 2020. All patients who underwent head CT during this period where review both indication and the CT finding. Result: out of 1000 CT brain request, 115 patients meet the inclusion criteria, and 13 patients from the inclusion criteria have stroke with isolated dizziness. 80% of brain CT was normal, while 11% showed acute stroke. Conclusion: patient present with dizziness carry the risk to have stroke and head CT brain can help in diagnosis. Adding further imaging, such as, brain perfusion study and MRI can lower the chance of missing stroke case in isolated dizziness presentation.

Antikoagülan ve/veya Antiplatelet Tedavi Kullanan Hafif Kafa Travmalı Hastalarda Başlangıçta Normal olan Bilgisayarlı Kafa Tomografisini Tekrarlamamız Gerekir mi?

Objective: Patients using anticoagulant and/or antiplatelet (AC/AP) medications are at an increased risk of intracranial hemorrhage (ICH) subsequent to head trauma and current guidelines recommend a head computed tomography (CT) scan for these patients. There is a lack of consensus about management recommendations for mild head trauma patients on AC/AP treatment who had an initially normal head CT. The aim of this study was to determine the rate of delayed ICH after a 24-hour observation in patients with mild head trauma using AC/AP who had an initially normal head CT. Method: Patients aged 18 and older, using AC/AP drugs with mild head trauma were included prospectively. Patients underwent head CT for suspected bleeding. A repeat CT scan was performed after a 24-hours observation period for the patients who had an initially normal head CT for detecting delayed intracranial hemorrhage. Result: A total of 101 patients were included and, 57.4% (n=58) of the patients were female. Delayed ICH was detected in 2.9% (n=3) of the patients after a 24-hour observation. None of the patients with delayed ICH needed surgical treatment or further intervention. Delayed ICH was found in patients who used acetylsalicylic acid (n=1), dabigatran (n=1), and apixaban (n=1). Conclusion: In patients with mild head trauma using AC/AP, delayed intracranial hemorrhage is rare and may be clinically insignificant. A repeat CT scanning after 24-hour observation may not be necessary for patients with mild head trauma using AC/AP therapy who had initially normal head CT.

Pediatric Brain Tumor Risk Associated with Head Computed Tomography: Systematic Literature Review

Computed tomography (CT) of the brain has changed diagnostic neuroradiology significantly over the past 50 years since it was firstly used back in 1971 to visualize suspected frontal lobe tumour. The safety of head CT is determined by the small amount of radiation and the low sensibility of brain tissue to cytotoxic damage due to ionizing radiation compared to other organs. However, some population groups may be at increased risk. Thus, children are more susceptible to radiation cancer than adults and lifelong attributive risk (LAR) can be more than 10 times higher for an infant than for a middle-aged adult. The authors have reviewed published studies that examined the prevalence and mortality of intracranial tumors in children undergoing head CT in comparison to unaffected individuals. Electronic search of publications in the PubMed database from 1966 to date was carried out. We have carried out intersectoral search for documents containing keywords or medical subject headings (MeSH) related to three wide categories: 1) computed tomography, 2) radiation-induced tumors, 3) risk, morbidity or epidemiology. Further search was performed in manual mode. Available epidemiological data generally confirmed correlation between head CT and tumor growth induction. Thus, current epidemiological data accept the opinion that the risk of tumor induction associated with head CT in children is very small (one tumor per 3,000–10,000 studies). The minimal estimated risk of tumor induction due to head CT in children is mostly offset by its diagnostic imaging benefits considering the clinical indications to minimize radiation dose. Understanding and quantitative risk assessment of carcinogenesis associated with CT imaging led to dose reduction in pediatric CT protocols. This trend should continue and should be implemented in all age groups. Although the decision to perform head CT is often undeniable (injury or hemorrhage), careful assessment of studies frequency is required, especially in patients who need disease monitoring. Cumulative effect in such cases may increase the minimal risk of carcinogenesis. Larger and advanced epidemiological studies are required to better understand these risks.

Assessing Radiation Dosage in Pediatric Head and Neck Computed Tomography Examinations During COVID-19 in a Tertiary Hospital in Saudi Arabia, Jeddah.

This study aimed to assess the practice of imaging and optimization of the radiation dose in pediatric head and neck computed tomography (CT) examinations during thecoronavirus disease of 2019 (COVID-19) period. This study is based on a retrospective analysis of pediatric head CT records, conducted in the Radiology Department of the King Abdulaziz University Hospital in Jeddah, Saudi Arabia. We examined the data of all pediatric patients between 0 and 14 years of age who underwent head CT scans between March and September in both 2019 (before the COVID-19 pandemic) and 2020 (during the COVID-19 pandemic). In total, we analyzed 1005 scans; 531 (52.8%) were performed before and 474 (47.2%) during COVID-19. The dose parameters were similar; however, the exposure time was significantly lower during COVID-19 (5432 ms vs. 5811 before; p < 0.001). In contrast, themean total CTDIvol and dose-length product (DLP) were slightly higher during COVID-19 than those before (23.34mGy vs.22.04mGy (p-value=0.565) and 577.36mGy*cm vs. 518.93mGy*cm (p-value=0.193) respectively). These changes could be attributed to the desire to limit the contact between technicians and patients. The limitation of contact with the patient allows the technicians to be independent during the scan, possibly accounting for this slight decrease.

Impact of a Faster Computed Tomography Scanner on Sedation for Pediatric Head Computed Tomography Scans in 2 Large Emergency Departments-A Retrospective Study.

Children in the emergency department (ED) often require sedation for head computed tomography (CT) to ensure adequate image quality. Image acquisition time for a head CT using a conventional single-source CT scanner is approximately 12 seconds; however, after installation in November 2017 of 2 new dual-source dual-energy CT scanners, that time decreased to 1 to 3 seconds. We hypothesized that fewer patients would require sedation using the faster CT scanners. We conducted a retrospective chart review of patients aged 0 to 18 years undergoing head CT at 2 pediatric EDs within 1 hospital system, 2 years before and 2 years after installation of the faster CT scanner. Patients undergoing multiple CTs or other procedures were excluded. Demographic information, diagnosis, disposition, sedatives (chloral hydrate, dexmedetomidine, etomidate, fentanyl, ketamine, midazolam, methohexital, pentobarbital, and propofol) administered before imaging, and ED length of stay were analyzed. A total of 15,175 patient encounters met inclusion criteria, 7412 before and 7763 after installation of the new CT. The median age was 7 years and 44% were female. Before the new CT scanner was installed 8% required sedation, compared with 7% after (effect size, 0.0341). Midazolam was the most commonly administered sedative. Fewer patients required deep sedation using the faster CT scanner. After installation of a dual-source dual-energy CT scanner, fewer patients required sedation to complete head CT in the pediatric ED. Faster image acquisition time decreased the need for deep sedation.

Incidence of surgically treated post-traumatic hydrocephalus 6 months following head injury in patients undergoing acute head computed tomography

BackgroundPost-traumatic hydrocephalus (PTH) is a well-known complication of head injury. The percentage of patients experiencing PTH in trauma cohorts (0.7–51.4%) varies greatly in the prior literature depending on the study population and applied diagnostic criteria. The objective was to determine the incidence of surgically treated PTH in a consecutive series of patients undergoing acute head computed tomography (CT) following injury.MethodsAll patients (N = 2908) with head injuries who underwent head CT and were treated at the Tampere University Hospital’s Emergency Department (August 2010–July 2012) were retrospectively evaluated from patient medical records. This study focused on adults (18 years or older) who were residents of the Pirkanmaa region at the time of injury and were clinically evaluated and scanned with head CT at the Tampere University Hospital’s emergency department within 48 h after injury (n = 1941). A thorough review of records for neurological signs and symptoms of hydrocephalus was conducted for all patients having a radiological suspicion of hydrocephalus. The diagnosis of PTH was based on clinical and radiological signs of the condition within 6 months following injury. The main outcome was surgical treatment for PTH. Clinical evidence of shunt responsiveness was required to confirm the diagnosis of PTH.ResultsThe incidence of surgically treated PTH was 0.15% (n = 3). Incidence was 0.08% among patients with mild traumatic brain injury (TBI) and 1.1% among those with moderate to severe TBI. All the patients who developed PTH underwent neurosurgery during the initial hospitalization due to the head injury. The incidence of PTH among patients who underwent neurosurgery for acute traumatic intracranial lesions was 2.7%.ConclusionThe overall incidence of surgically treated PTH was extremely low (0.15%) in our cohort. Analyses of risk factors and the evaluation of temporal profiles could not be undertaken due to the extremely small number of cases.

Premedication with Hydrocortisone Increases Risk of Adverse Drug Events and Return to Medical Care Among Pediatric Patients with ITP Treated with IVIG

Immune Thrombocytopenia (ITP) is one of the most common acquired bleeding disorders affecting children. While 75-80% of these children will develop only mild bleeding symptoms, others can experience more severe bleeding, including rare intracranial hemorrhage (ICH), and may require platelet-directed therapy. Intravenous immunoglobulin (IVIG), a commonly utilized and effective first-line therapy, may be associated with adverse drug events (ADEs). The most commonly reported ADEs include headache (approximately 30% of treated patients) and nausea/vomiting, however the exact rates of these events and relationship to premedication strategies are poorly classified. These ADEs often result in emergent medical evaluation and additional diagnostic testing, including computed tomography (CT) of the head, to evaluate for ICH in children with severe thrombocytopenia.In order to identify rates of IVIG-associated ADEs and subsequent emergent medical evaluations in pediatric patients with ITP, we completed an retrospective observational cohort study of all pediatric patients with ITP who were treated with one-time IVIG infusion utilizing Gamunex-C ® 10% at a dose of 1g/kg across 4 large pediatric centers from 2010 to 2019. Included patients were between the ages of 0 and 21 years.Among the 563 patients receiving single IVIG infusions across all 4 centers, patients reported headache, nausea/vomiting, or both following 203 infusions (36%). Excluding those patients who remained hospitalized at the time of symptom development, 16% (84 of 513) of all patients returned for urgent medical evaluation following IVIG infusion. Nine percent of all patients receiving a single IVIG infusion underwent head CT to rule out ICH. All 51 CTs were negative for ICH.In order to determine if specific patient characteristics were associated with the development of IVIG-associated ADEs and return to medical care, univariable logistic regression was performed. Multiple logistic regression was used to determine whether the associations identified in the univariable analysis persisted after adjusting for other significant factors. Older age at administration (Adjusted Odds Ratio [adj OR] 1.07 for each additional year of age; 95% Confidence Interval [CI] 1.03, 1.11; p<0.001) and premedication with hydrocortisone (adj OR 2.36; 95% CI 1.38, 4.07; p=0.002) were associated with increased odds of IVIG-associated ADEs. Patients who received premedication with hydrocortisone were more likely to re-present for medical evaluation than patients who did not receive hydrocortisone (OR 1.90; 95% CI 0.98, 3.54; p=0.049). No associations were identified between ADEs and gender, race/ethnicity, premedication with diphenhydramine or ondansetron, pre-treatment serum IgG levels, or concurrent glucocorticoid administration.In summary, the rate of ADEs among pediatric patients with ITP treated with IVIG is remarkably high. Thirty-six percent of patients in our multi-institutional cohort reported headache, nausea/vomiting, or both following single IVIG infusion, consistent with our previous single institution experience. This again highlights the need for proper balance of risks and benefits when considering treatment for children with ITP. Patients who received premedication with acetaminophen were less likely to develop IVIG-associated ADEs, but those who received premedication with diphenhydramine or concurrent glucocorticoid therapy were no more or less likely to develop ADEs. Interestingly, however, patients who received premedication with hydrocortisone were more likely to develop IVIG-associated ADEs. Despite only a small subset of our cohort being premedicated with hydrocortisone (12%, n=66), this premedication strategy was significantly associated with an increased rate of return to medical care following IVIG infusion. Patients returning for emergent medical evaluation frequently underwent repeat laboratory studies or CT imaging, resulting in unnecessary radiation exposure and increased healthcare-related costs. These findings will help to inform IVIG premedication strategies in an attempt to reduce both ADEs and re-presentation to medical care among pediatric patients with ITP receiving IVIG therapy. [Display omitted] DisclosuresKirk: Biomarin: Honoraria. Grace: Novartis: Research Funding; Principia: Membership on an entity's Board of Directors or advisory committees; Dova: Membership on an entity's Board of Directors or advisory committees, Research Funding; Agios: Research Funding. Neunert: Novartis: Research Funding. Lambert: Bayer: Consultancy; ClinGen, ISTH, ASH, GW University: Honoraria; Novartis: Consultancy, Honoraria, Research Funding; Astra Zeneca: Research Funding; Argenx: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Principia: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Dova: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; Shionogi: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees; Rigel: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding; PDSA: Research Funding; Sysmex: Research Funding; Octapharma: Consultancy, Honoraria, Membership on an entity's Board of Directors or advisory committees, Research Funding. Despotovic: UpToDate: Patents & Royalties: Royalties; Apellis: Consultancy; Novartis: Consultancy, Research Funding; Agios: Consultancy.

Pathological Computed Tomography Features Associated With Adverse Outcomes After Mild Traumatic Brain Injury

A head computed tomography (CT) with positive results for acute intracranial hemorrhage is the gold-standard diagnostic biomarker for acute traumatic brain injury (TBI). In moderate to severe TBI (Glasgow Coma Scale [GCS] scores 3-12), some CT features have been shown to be associated with outcomes. In mild TBI (mTBI; GCS scores 13-15), distribution and co-occurrence of pathological CT features and their prognostic importance are not well understood. To identify pathological CT features associated with adverse outcomes after mTBI. The longitudinal, observational Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study enrolled patients with TBI, including those 17 years and older with GCS scores of 13 to 15 who presented to emergency departments at 18 US level 1 trauma centers between February 26, 2014, and August 8, 2018, and underwent head CT imaging within 24 hours of TBI. Evaluations of CT imaging used TBI Common Data Elements. Glasgow Outcome Scale-Extended (GOSE) scores were assessed at 2 weeks and 3, 6, and 12 months postinjury. External validation of results was performed via the Collaborative European NeuroTrauma Effectiveness Research in Traumatic Brain Injury (CENTER-TBI) study. Data analyses were completed from February 2020 to February 2021. Acute nonpenetrating head trauma. Frequency, co-occurrence, and clustering of CT features; incomplete recovery (GOSE scores <8 vs 8); and an unfavorable outcome (GOSE scores <5 vs ≥5) at 2 weeks and 3, 6, and 12 months. In 1935 patients with mTBI (mean [SD] age, 41.5 [17.6] years; 1286 men [66.5%]) in the TRACK-TBI cohort and 2594 patients with mTBI (mean [SD] age, 51.8 [20.3] years; 1658 men [63.9%]) in an external validation cohort, hierarchical cluster analysis identified 3 major clusters of CT features: contusion, subarachnoid hemorrhage, and/or subdural hematoma; intraventricular and/or petechial hemorrhage; and epidural hematoma. Contusion, subarachnoid hemorrhage, and/or subdural hematoma features were associated with incomplete recovery (odds ratios [ORs] for GOSE scores <8 at 1 year: TRACK-TBI, 1.80 [95% CI, 1.39-2.33]; CENTER-TBI, 2.73 [95% CI, 2.18-3.41]) and greater degrees of unfavorable outcomes (ORs for GOSE scores <5 at 1 year: TRACK-TBI, 3.23 [95% CI, 1.59-6.58]; CENTER-TBI, 1.68 [95% CI, 1.13-2.49]) out to 12 months after injury, but epidural hematoma was not. Intraventricular and/or petechial hemorrhage was associated with greater degrees of unfavorable outcomes up to 12 months after injury (eg, OR for GOSE scores <5 at 1 year in TRACK-TBI: 3.47 [95% CI, 1.66-7.26]). Some CT features were more strongly associated with outcomes than previously validated variables (eg, ORs for GOSE scores <5 at 1 year in TRACK-TBI: neuropsychiatric history, 1.43 [95% CI .98-2.10] vs contusion, subarachnoid hemorrhage, and/or subdural hematoma, 3.23 [95% CI 1.59-6.58]). Findings were externally validated in 2594 patients with mTBI enrolled in the CENTER-TBI study. In this study, pathological CT features carried different prognostic implications after mTBI to 1 year postinjury. Some patterns of injury were associated with worse outcomes than others. These results support that patients with mTBI and these CT features need TBI-specific education and systematic follow-up.

Correlated Imaging of the Equine Hyoid Apparatus Using CT, Micro-CT, and Histology.

Background: Detailed radiological evaluation of the normal hyoid apparatus by computed tomography (CT) has not yet been conducted. Thus, it is unclear what type of junction connects the different parts of the equine hyoid apparatus.Objectives: To describe the normal CT anatomy of the equine hyoid apparatus, and to determine the junction type that connects the different parts of the hyoid apparatus.Study Design: Combination of retrospective study and prospective cadaver study.Methods: The medical records of horses that underwent head CT scans from 2009 to 2018 were retrieved. Inclusion criteria for the CT scans were visibility of at least two of the four junctions of the hyoid apparatus. CT images were analyzed in three different planes. Additionally, 10 cadaver heads were processed using CT, micro-CT of selected joints, and histology of all joints.Results: CT scans of 200 horses fulfilled the inclusion criteria. The tympanohyoid cartilage consisted of hyaline cartilage. Areas of mineralization within the cartilage were visible on CT scans as early as 2 years of age. The epihyoid was not fused with the stylohyoid in one-third of the horses. All horses younger than 2.5 years showed three ossification centers of the basihyoid, and all horses younger than 1.5 years had a non-fullydeveloped lingual process. In total, 10 of 11 horses between 1.5 and 3 years had separate ossification centers of the lingual process. We found a synchondrosis between the styloid process and the stylohyoid bone. The basihyoid and thyrohyoid, as well as the stylohyoid and epiyhoid were connected by a synostosis in two-thirds of the horses. The remaining parts were connected to one another by synovial joints.Main limitations: The junctions studied by histologic examination were from older horses, therefore growing patterns of different bones could not be totally clarified.Conclusion: The temporohyoid joint is a synchondrosis. The epihyoid is an ossification center of the stylohyoid and fuses with the stylohyoid in two-thirds of horses. The lingual process has a separate ossification center.

Utility of non-contrast head computed tomography in poisoned patients.

To investigate the utility of non-contrast head computed tomography (CT) in poisoned patients. A retrospective cohort study of patients referred to a toxicology unit between August 2010 and December 2017. Our database yielded patients who underwent head CT at presentation to the ED. Pre-specified information was compiled from the medical records. There were 6261 presentations of which 1142 underwent head CT (17%). Median age was 41 years, and 437 (38%) were female. There were 492 (43%) recreational ingestions and 466 (41%) deliberate self-poisonings. The commonest agents were sedatives 376 (33%) and opioids 282 (24%); 334 (29%) cases were intubated. Signs of head injury were found in 153 cases (13%) and focal neurological signs in 68 (6%). No acute pathology was reported in 884 head CTs (77%), chronic changes in 193 (17%) and incidental findings in 26 (2%). Acute pathology was found in 39 (4%) patients: 15 with hypoxic-ischaemic injury, three infarctions, nine with intra-cranial haemorrhage, 11 facial bone fractures and one retro-bulbar haematoma. No patient required an immediate surgical intervention, and only one patient had a change to clinical treatment. Acute head CT pathology was associated with at least one of the following clinical features: need for intubation, signs of head injury, seizure, headache, and unexpected neurological signs. Non-contrast head CT is a low-yield investigation in patients presenting with poisoning. Consideration should be given as to whether the clinical presentation is consistent with the expected toxidrome and whether the patient would benefit from head CT.

The utility of brain CT scan modality in the management of dizziness at the emergency department: A retrospective single-center study

ObjectivesThis study examines the usefulness of computed tomography (CT) scans in evaluating patients with dizziness in the emergency department (ED). MethodsMedical records of patients presented with complaints of dizziness or vertigo to the ED of a tertiary university hospital and underwent head CT scans from July 2015 to June 2018 were reviewed. The patients’ demographic information, presenting symptoms, and final head CT scan and Magnetic resonance imaging (MRI) results were collected. Stepwise logistic regressions were used to analyze data. ResultsA total of 326 dizzy patients were included in this study. The majority of the patients (83.1%) were older than 44 years. Acute vertigo pattern of dizziness was detected among 50.6% of the patients and was more common among females than males (p < 0.001). Of these 326 patients who underwent head CT scans, 49 (15%) had abnormal findings with acute ischemic stroke was the most common one. A total of 191 patients underwent follow-up studies. MRI accounted for 70% of the follow-up studies. Of the 134 patients who received MRI of the brain, 36 (27%) had abnormal findings. A significant correlation of RBCs level, presence of other symptoms, and frequency of episodes with the presence of vertigo (p < 0.001) was found. ConclusionThe study's findings indicate low effectiveness of head CT scan compared to MRI for dizziness management. Future studies are suggested to provide more insights into the cost-effectiveness and utility of head CT scans and MRI in providing valuable findings.

An Observation of Application of Structural Brain Injury Devices for Traumatic Brain Injury Evaluation in Austere Military Prehospital Settings.

Military units lack the ability to quickly, objectively, and accurately assess individuals that have suffered a closed head injury for structural brain injury and functional brain impairments in forward settings, where neurological assessment equipment and expertise may be lacking. With acute traumatic brain injury patients, detached medical providers are often faced with a decision to wait and observe or medically evacuate, both of which have cascading consequences. Structural brain injury assessment devices, when employed in forward environments, have the potential to reduce the risk of undiagnosed and/or mismanaged traumatic brain injuries given their high negative predictive value and suggested increased specificity compared to common subjective clinical decision rules. These handheld devices are portable and have an ease of use, from combat medic to physician, allowing for use in austere environments, safely keeping soldiers with their teams when able and suggesting further evaluation via computed tomography (CT) scan when warranted. Data collected on 13 encounters at 5 locations were retrospectively analyzed using descriptive statistics. A total number of 13 examinations were performed using the BrainScope One device during the 9-month deployment. The Structural Injury Classification was negative for 11 of the patients. Two of the 11 patients underwent head CT scans, which confirmed the absence of intracranial hemorrhage. Of the two positive Structural Injury Classification exams, one was CT negative and no CT was performed for the other based on clinical judgment. The data from this study suggest that structural brain injury devices may provide value by ruling out serious brain injury pathology while limiting excessive medical evacuations from austere settings, where neurological assessment equipment and expertise may be lacking, reducing unnecessary head CT scans.

Ultra-Low-Dose Computed Tomography Protocol for Preoperative Evaluation in Children With Craniofacial Anomalies.

Preoperative three-dimensional computed tomography is currently the gold standard imaging modality in patients with craniofacial anomalies. In these patients, bone structural evaluation is paramount for surgical planning and evaluation of brain parenchyma is often secondary. With the significant complexity of these patients, a majority of patients undergo multiple Computed Tomography (CT) studies from infancy into adulthood. This study presents an ultra-low-dose CT protocol that limits the radiation exposure per CT scan in patients with craniofacial anomalies. A total of 200 consecutive patients who underwent head CT for preoperative evaluation of craniofacial anomalies at Tertiary Children's Hospital were included in the study. The kVp, (KiloVoltage Peak) mA (milliAnperage), CT dose index (CTDI), and dose-length product (DLP) were documented from the dose page. Patients were stratified based on age for determining age specific effective dose and for age matched comparison. The age specific effective dose was derived by using the established conversion factor as described in the paper. (1) Standard t test was performed to determine the statistical significance of radiation dose reduction. The Institutional Review Board approved the study and data was collected from 2012-2014. Of the 200 patients assessed in our study, 90 patients had low-dose CT scans and 110 patients had ultra-low-dose CT scans of the head. All patients had diagnostic quality CT studies. The low-dose CT was performed at 120 kVp and 100 mA. The ultra-low-dose CT was performed at 80 kVp and fixed 80 mA. The minimum, maximum and mean effective dose before the introduction of the ultra-low-dose protocol was 0.8 mSv, 6.9 mSV and 2.82 mSv. The minimum, maximum and mean effective dose after the introduction of the ultra-low-dose protocol was 0.6 mSv, 3.8 mSV, and 1.37 mSv. The reduction in the effective radiation dose was statistically significant (standard t test; P = 0.0001). Compared to the regular low-dose protocol, the ultra-low-dose CT protocol provided appropriate diagnostic images with a significantly decreased radiation dose.