Initial Computed Tomography Research Articles

Inter-observer variability with five computed tomography severity scales for COVID-19 pneumonia assessment.

By the end 2019 there was an outbreak of pneumonia caused by a new coronavirus, a disease that was called coronavirus disease 2019 (COVID-19). Computed tomography (CT) has played an important role in the diagnosis of COVID-19 patients. To demonstrate inter-observer variability with five scales proposed for measuring the extent of COVID-19 pneumonia on tomography. Thirty five initial chest CT scans of patients who attended respiratory triage for suspected COVID-19 pneumonia were analyzed. Three radiologists classified the tomographic images according to the severity scales proposed by Yang (1), Yuan (2), Chun (3), Wang (4) and Instituto Nacional de Enfermedades Respiratorias-Chung-Pan (5). The percentage of agreement between the evaluators for each scale was calculated using the intra-class correlation index. In most patients were five pulmonary lobes compromised (77.1% of the patients). Scales 1, 2, 4 and 5 showed an intra-class correlation > 0.91 (p < 0.0001), with agreement thus being almost perfect. Scale 4 (proposed by Wang) showed the best inter-observer agreement, with a coefficient of 0.964 (p = 0.001).

SurVolT: Surface to Volume conversion Tool. A proof of concept

Purpose:To develop SurVolT, a conversion tool able to apply volumetric changes to DICOM Computed Tomography (CT) data using daily surface (obj) data acquired with AlignRT® (VisionRT Ltd.), primarily designed and validated for breast treatments. Materials and Methods:SurVolT proceeds in 4 steps: 1. AlignRT .obj files extraction, 2. Contour deformation where the surface data points are matched to the initial external contour on a Region Of Interest, ROImatch, on which the anatomy is supposed to be unchanged. Then, external contour substitution is performed on the ROIttt covering the treated breast area. This is validated on a female torso phantom with a tissue-equivalent bolus mimicking an edema. The Planning Treatment Volume (PTV) contour from the initial CT is also deformed according to the new external contour in the ROIttt. 3. Volumetric data estimation according to the new external contour, validated on an anthropomorphic pelvis phantom. 4. Import of new DICOM data into the Treatment Planning System (TPS). Finally, the workflow is applied on a first patient presenting an anatomical change during the treatment. Results:The validation of step 2 and 3 shows a bolus thickness estimation of 5.8±1.2mm (expected 5 mm) and the non-rigid deformation of initial CT images follows the new external contour at the ROIttt bolus site while revealing negligible deformation elsewhere. Conclusion:This first proof of concept introducing a Surface Guided Radiotherapy (SGRT) tool allowing daily surface data to volume conversion is a fundamental step toward SGRT-based adaptive radiotherapy.

Misinterpretation of a giant idiopathic concealed right iliac artery aneurysm as infantile pelvic tumor imaged by non-angiographic computed tomography: a case report

BackgroundIdiopathic pediatric artery aneurysm is extremely rare and sometimes behaves like a pelvic neoplasm. As it is associated with a high mortality while ruptured, the accurate diagnosis is indispensable to avoid life-threatening complications. Angiographic imaging is the gold standard for diagnosis and treatment planning of the aneurysm. Due to the considerably higher radiation sensitivity of children, single portal venous-phase scanning of the abdominopelvic computed tomography (CT) is, however, reasonably utilized for the evaluation of a clinically palpable mass; the erroneous diagnosis of such aneurysm can be feasible.Case presentationA giant idiopathic concealed right iliac artery aneurysm in a 47-day-old girl presented with a palpable pelvic mass regardless of unidentifiable predisposing factors. Non-angiographic abdominopelvic CT was reappraised by the radiology consultant according to discordance between the mass characteristics on initial CT report and those on second-look sonography, revealing the concealed aneurysm instead of solid neoplasm as it originated from right internal iliac artery. The patient underwent an emergency laparotomy with successful proximal ligation of right internal iliac artery despite intraoperative aneurysmal rupture.ConclusionsTypical CT features for the infantile iliac artery aneurysms may be overlooked, especially if the angiographic phase is omitted; thus, the imaging characteristics of the aneurysms are more difficult to appreciate and can mimic a pelvic neoplasm. Therefore, the identification of the origin of the mass should be more practical to achieve the precise diagnosis.

Circulating tumor DNA in molecular assessment feasibly predicts early progression of pancreatic cancer that cannot be identified via initial imaging

Molecular assessment using circulating tumor DNA (ctDNA) has not been well-defined. We recruited 61 pancreatic cancer (PC) patients who underwent initial computed tomography (CT) imaging study during first-line chemotherapy. Initial molecular assessment was performed using droplet digital PCR and defined as the change in KRAS-mutated ctDNA before and after treatments, which was classified into five categories: mNT, molecular negative; mCR, complete response; mPR, partial response; mSD, stable disease; mPD, progressive disease. Of 61 patients, 14 diagnosed with PD after initial CT imaging showed significantly worse therapeutic outcomes than 47 patients with disease control. In these 47 patients, initial molecular assessment exhibited significant differences in therapeutic outcomes between patients with and without ctDNA (mPD + mSD vs. mCR + mNT; 13.2 M vs. 21.7 M, P = 0.0029) but no difference between those with mPD and mSD + mCR + mNT, suggesting that the presence of ctDNA had more impact on the therapeutic outcomes than change in its number. Multivariate analysis revealed that it was the only independent prognostic factor (P = 0.0405). The presence of ctDNA in initial molecular assessment predicted early tumor progression and identified PC patients more likely to benefit from chemotherapy.

Renal colic imaging practice patterns in Ontario A population-based study.

Computed tomography (CT) is associated with increased cost and exposure to radiation when compared to ultrasound (US) in patients with renal colic. Consequently, a 2014 Choosing Wisely recommendation states US should be used over CT in uncomplicated presentations in patients under age 50. The objective of this study was to describe imaging practice patterns in Ontario among patients presenting with renal colic and the relationship between initial imaging modality, subsequent imaging, and burden of care indicators. This is a population-based study of patients who presented with renal colic in Ontario from 2003-2019 using administrative data. Patients were assessed according to their first imaging modality during their index visit. Descriptive statistics and Chi-squared test were used to examine differences between these groups. The primary outcome was the need for subsequent imaging. Secondary outcomes were length of renal colic episode, days to surgery, and number of emergency department (ED ) and primary care visits during the renal colic episode. Univariate and multivariable logistic regression models were used. A total of 429 060 patients were included in the final analysis. Of those, 50.5% (216 747) had CT as their initial imaging modality, 20% (84 672) had US, and 3% (13 643) had both on the same day. Subsequent imaging was obtained in 40.7% of those who had CT as the initial imaging, compared to 43% in those who had US and 43% who had both. Of those who initially had an US, 38% went on to have at least one CT during their renal colic episode, including those who had CT on the same day as initial US, while 62% were able to avoid CT altogether. In contrast, 17% had a repeat CT after an initial CT at the time of presentation. The overall use of US increased from 15% to 31% during the study period. The length of the renal colic episode was slightly longer in those who had a CT first compared to US in multivariable models (adjusted risk ratio [ARR ] 1.005, 95% confidence interval [CI] 1.000-1.009); however, the time to surgery was less in those who had a CT first (ARR 0.831, 95% CI 0.807-0.856). Fewer ED and family physician visits were seen in those who had an initial CT. In patients with renal colic in Ontario, approximately half have CT as the initial imaging modality despite US being recommended in uncomplicated presentations. While US use remains low, its use doubled during this study period, demonstrating an encouraging trend. Those who have US first can often avoid subsequent CT.

The effect of CT-based cardiothoracic ratio on survival of COVID-19 patients

Objectives: We aimed to investigate the relationship between computed tomography (CT)- based cardiothoracic ratio (CTR) with mortality rates of COVID-19 patients. Methods: Our study was a single-center retrospective analysis of 484 patients (aged ≥ 18) who were admitted to our hospital’s emergency department. We included only laboratory-confirmed COVID-19 patients who underwent chest CT. Data of demographic information, laboratory findings, survivals, and chest CT imaging findings were recorded. The radiologist calculated CTR by dividing the greatest transverse cardiac diameter by the greatest transverse thoracic diameter on the initial chest CT. Cardiomegaly was defined if “CTR &amp;gt; 0.5”. Results: Thirty (6.2%) patients were treated as outpatients, and 135/484 (%27.9) patients were treated in the intensive care unit (ICU). A total of 147 /484 (30.4%) patients died. We found a statistical association between cardiomegaly with mortality rates (p &amp;lt; 0.001) and ICU admission (p = 0.008). In multivariate analysis, older age was 1.07-fold (p &amp;lt; 0.001), cardiomegaly 1.75-fold (p = 0.015), history of cerebrovascular diseases 2.929-fold (p = 0.018), and elevated serum LDH level 1.003-fold (p = 0.011) associated with higher risks of mortality. Conclusions: Since the presence of cardiomegaly on chest CT is associated with a worse prognosis for COVID-19 patients, more caution should be exercised in the evaluation, follow-up, and treatment of COVID-19 patients with cardiomegaly.

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.

Abstract Number ‐ 185: Variable Presentation of Basilar Occlusion: Lessons to be Learned

Introduction To present a case of basilar thrombosis with lessons for improving care. Methods Case presentation Results 89 year old Female with history of coronary artery disease with prior stenting brought in by ambulance for cardiac arrest. Patient last known normal 0900 per son. At 1100 patient called EMS for sudden onset nausea with projectile emesis. On arrival EMS staff noted patient to be walking and talking and administered zofran. After eight to ten minutes staff witnessed patient undergo cardiopulmonary arrest and initiated cardiac compressions. Return of spontaneous cardiac activity achieved after one dose of epinephrine and two minutes of compressions. In emergency department at 1132 patient moving extremities and following commands but intubated for encephalopathy and hypoxia. Computed Tomography (CT) head without contrast performed at 1222 showed hypodensity in left occipital lobe and left cerebellum suspicious for infarct. Neurology consulted routinely and National Institute of Health Stroke Scale (NIHSS) 21. Stat CT angiography of head and neck completed at 1657 and showed complete occlusion of basilar artery from origin to terminus. Patient evaluated by neurology fellow and found to be unresponsive with decerebrate posturing, NIHSS maximal; Neurosurgery service was paged at 1659 for stat evaluation. Patient arrived at cath lab at 1949 and thrombectomy performed with TICI 2b. Magnetic Resonance Imaging of brain performed next day at 432 showed diffuse diffusion restriction and T2 signal in bilateral occipital lobes, temporal lobes and thalami, throughout midbrain and pons consistent with acute/subacute infarct. Patient was transitioned to comfort care and extubated. Conclusions Acute basilar occlusion is recognized as a potentially treatable condition if diagnosed quickly. Outcomes of these infarcts remain poor but recent evidence from ATTENTION and BOAChE studies has shown that treatment by emergent thrombectomy provides for better outcomes than medical management alone despite higher risk of intracranial hemorrhage and that these benefits can be seen after 12 to 24 hours from symptom onset(1,2). This particular case is unique not only due to the rarity of stroke presenting as intractable emesis but also in its illustration of diagnostic pitfalls of posterior circulation (3,4). In order to provide appropriate treatment, recognition of abnormal presentation of basilar thrombosis becomes increasingly important. Paul et al identified isolated vertigo, vertigo with non‐focal symptoms, isolated double vision, transient generalized weakness, and binocular visual disturbance as significant transient symptoms preceding basilar occlusion (5). Savitz and Caplan report, “most common signs are limb weakness, gait and limb ataxia, oculomotor palsies, and oropharyngeal dysfunction” but also note that vomiting, vertigo, visual loss, numbness can also occur (6). Additionally this patient initial CT scan showed possible stroke but did not identify vessel occlusion. Developments in artificial intelligence are working towards identifying large vessel occlusion on plain noncontrast CT which would have benefitted this patient.

COVID-19 Chest CT Quantification: Triage and Prognostic Value in Different Ages.

Objective: We evaluated the triage and prognostic performance of seven proposed computed tomography (CT)-severity score (CTSS) systems in two different age groups.Design: Retrospective study.Setting: COVID-19 pandemic.Participants: Admitted COVID-19, PCR-positive patients were included, excluding patients with heart failure and significant pre-existing pulmonary disease.Methods: Patients were divided into two age groups: ≥65 years and ≤64 years. Clinical data indicating disease severity at presentation and at peak disease severity were recorded. Initial CT images were scored by two radiologists according to seven CTSSs (CTSS1-CTSS7). Receiver operating characteristic (ROC) analysis for the performance of each CTSS in diagnosing severe/critical disease on admission (triage performance) and at peak disease severity (prognostic performance) was done for the whole cohort and each age group separately.Results: Included were 96 patients. Intraclass correlation coefficient (ICC) between the two radiologists scoring the CT scan images were good for all the CTSSs (ICC=0.764-0.837). In the whole cohort, all CTSSs showed an unsatisfactory area under the curve (AUC) in the ROC curve for triage, excluding CTSS2 (AUC=0.700), and all CTSSs showed acceptable AUCs for prognostic usage (0.759-0.781). In the older group (≥65 years; n=55), all CTSSs excluding CTSS6 showed excellent AUCs for triage (0.804-0.830), and CTSS6 was acceptable (AUC=0.796); all CTSSs showed excellent or outstanding AUCs for prognostication (0.859-0.919). In the younger group (≤64 years; n=41), all CTSSs showed unsatisfactory AUCs for triage (AUC=0.487-0.565) and prognostic usage (AUC=0.668-0.694), excluding CTSS6, showing marginally acceptable AUC for prognostic performance (0.700).Conclusion: Those CTSSs requiring more numerous segmentations, namely CTSS2, CTSS7, and CTSS5 showed the best ICCs; therefore, they are the best when comparison between two separate scores is needed. Irrespective of patients' age, CTSSs show minimal value in triage and acceptable prognostic value in COVID-19 patients. CTSS performance is highly variable in different age groups. It is excellent in those aged ≥65 years, but has little if any value in younger patients. Multicenter studies with larger sample size to evaluate results of this study should be conducted.

A Real-World Cost-Effectiveness Study Evaluating Imaging Strategies for the Diagnostic Workup of Renal Colic in the Emergency Department.

Introduction Both non-contrast Computed Tomography (CT) and ultrasound (US) are used for the diagnosis of renal colic in the emergency department (ED). Although US reduces radiation exposure, its diagnostic accuracy is inferior to that of CT. In this context, data regarding the cost and organizational impact of these strategies represent essential elements in the choice of imaging; however, they remain poorly documented. Aim of the study The aim of this study was to compare the costs and effectiveness of diagnostic workup by US and CT for patients consulting with renal colic in the ED. Methods We conducted a monocentric real-life retrospective study of patients consulting for a renal colic in an ED between 1 July 2018 and 31 December 2018. We estimated length of stay (LOS), total hospital costs at 60 days including ED, and initial and repeat admissions. Patients with initial US in the ED were compared to patients with initial CT using inverse probability weighting of the propensity score calculated from demographic variables, vital parameters, and clinical presentation. We calculated the incremental cost effectiveness ratio as the difference in costs by the difference in LOS. The variability of the results was assessed using non-parametric bootstrapping. Results In this study, of the 273 patients included, 67 were patients assessed with US and 206 with CT. The average costs were €1159 (SD 1987) and €956 (SD 1462) for US and CT, respectively, and the ED LOS was 8.9 [CI 95% 8.1; 9.4] and 8.7 [CI 95% 7.9; 9.9] hours for US and CT, respectively. CT was associated with a decreased LOS by 0.139 [CI 95% -1.1; 1.5] hours and was cost-saving, with a €199 [CI 95% -745; 285] reduction per patient. Conclusion When imaging is required in the ED for suspected renal colic as recommended, there is real-life evidence that CT is a cost-effective strategy compared to US, reducing costs and LOS in the ED.

COVID-19 therapy optimization by AI-driven biomechanical simulations.

The COVID-19 disease causes pneumonia in many patients that in the most serious cases evolves into the Acute Distress Respiratory Syndrome (ARDS), requiring assisted ventilation and intensive care. In this context, identification of patients at high risk of developing ARDS is a key point for early clinical management, better clinical outcome and optimization in using the limited resources available in the intensive care units. We propose an AI-based prognostic system that makes predictions of oxygen exchange with arterial blood by using as input lung Computed Tomography (CT), the air flux in lungs obtained from biomechanical simulations and Arterial Blood Gas (ABG) analysis. We developed and investigated the feasibility of this system on a small clinical database of proven COVID-19 cases where the initial CT and various ABG reports were available for each patient. We studied the time evolution of the ABG parameters and found correlation with the morphological information extracted from CT scans and disease outcome. Promising results of a preliminary version of the prognostic algorithm are presented. The ability to predict the evolution of patients' respiratory efficiency would be of crucial importance for disease management.

Computed Tomography Lesions and Their Association With Global Outcome in Young People With Mild Traumatic Brain Injury.

Mild traumatic brain injury (mTBI) can be accompanied by structural damage to the brain. Here, we investigated how the presence of intracranial traumatic computed tomography (CT) pathologies relates to the global functional outcome in young patients one year after mTBI. All patients with mTBI (Glasgow Coma Scale: 13-15) ≤24 years in the multi-center, prospective, observational Collaborative European NeuroTrauma Effectiveness Research in TBI (CENTER-TBI) study were included. Patient demographics and CT findings were assessed at admission, and the Glasgow Outcome Scale Extended (GOSE) was evaluated at 12 months follow-up. The association between a "positive CT" (at least one of the following: epidural hematoma, subdural hematoma, traumatic subarachnoid hemorrhage (tSAH), intraventricular hemorrhage, subdural collection mixed density, contusion, traumatic axonal injury) and functional outcome (GOSE) was assessed using multi-variable mixed ordinal and logistic regression models. A total of 462 patients with mTBI and initial brain CT from 46 study centers were included. The median age was 19 (17-22) years, and 322 (70%) were males. CT imaging showed a traumatic intracranial pathology in 171 patients (37%), most commonly tSAH (48%), contusions (40%), and epidural hematomas (37%). Patients with a positive CT scan were less likely to achieve a complete recovery 12 months post-injury. The presence of any CT abnormality was associated with both lower GOSE scores (odds ratio [OR]: 0.39 [0.24-0.63]) and incomplete recovery (GOSE <8; OR: 0.41 [0.25-0.68]), also when adjusted for demographical and clinical baseline factors. The presence of intracranial traumatic CT pathologies was predictive of outcome 12 months after mTBI in young patients, which might help to identify candidates for early follow-up and additional care.

Antisynthetase syndrome-related interstitial lung disease (ASyS-ILD): longitudinal imaging findings.

Interstitial lung disease (ILD) impacts mortality in antisynthetase syndrome (ASyS). Computed tomographic (CT) patterns and evolution in ASyS ILD are not well described. We report longitudinal CT patterns in ASyS-ILD and their impact on survival. This is a monocentric retrospective study of 47 patients with ASyS-ILD. Longitudinal CT patterns and fibrosis severity (severity of radiographic features indicating fibrosis) were analyzed by two radiologists in consensus. The association between imaging features and survival was examined using univariate Cox regression analysis. In total, 211 CT scans were analyzed with an average of 4 ± 2 CT scans/patient with a median follow-up of 79months in 47 patients. Non-fibrotic patterns were present initially in 63.8% (n = 30) of patients, while fibrotic patterns occurred in 36.2% (n = 17). The initial non-fibrotic patterns/abnormalities resolved in 23.3% (n = 7), evolved in 6.7% (n = 2), persisted in 13.3% (n = 4), and progressed in 56.7% (n = 17), while initial fibrotic patterns persisted in 82.4% (n = 14) and progressed in 17.6% (n = 3). Radiographic progression of ILD (progression in CT pattern or increased fibrosis severity) occurred in 53.2% (n = 25) of patients. Advanced age and radiographic progression were associated with decreased survival (all p < 0.05). The presence of ground-glass opacities (GGO) and predominant lower lung distribution of abnormalities on initial CTs were associated with increased survival (all p < 0.05). Progression occurred in 56.7% of ASyS-ILD patients presenting with non-fibrotic patterns. Fibrotic patterns tended to persist. Age and radiographic progression were associated with reduced survival while the initial presence of GGO and predominant lower lobe distribution were associated with increased survival. • In ASyS-ILD, initial non-fibrotic patterns such as OP, cNSIP, or OP-cNSIP tended to progress to fNSIP. • Fibrotic patterns such as fNSIP or UIP in ASyS-ILD tended to persist without pattern changes. • GGO and lower lung predominance on initial CT were associated with better survival while advanced baseline age and radiographic ILD progression during follow-up were associated with decreased survival.

Trends in oncological imaging during the COVID-19 pandemic through the vaccination era.

This study examines the impact that the COVID-19 pandemic has had on computed tomography (CT)-based oncologic imaging utilization. We retrospectively analyzed cancer-related CT scans during four time periods: pre-COVID (1/5/20-3/14/20), COVID peak (3/15/20-5/2/20), post-COVID peak (5/3/20-12/19/20), and vaccination period (12/20/20-10/30/21). We analyzed CTs by imaging indication, setting, and hospital type. Using percentage decrease computation and Student's t-test, we calculated the change in mean number of weekly cancer-related CTs for all periods compared to the baseline pre-COVID period. This study was performed at a single academic medical center and three affiliated hospitals. During the COVID peak, mean CTs decreased (-43.0%, p < 0.001), with CTs for (1) cancer screening, (2) initial workup, (3) cancer follow-up, and (4) scheduled surveillance of previously treated cancer dropping by 81.8%, 56.3%, 31.7%, and 45.8%, respectively (p < 0.001). During the post-COVID peak period, cancer screenings and initial workup CTs did not return to prepandemic imaging volumes (-11.4%, p=0.028; -20.9%, p=0.024). The ED saw increases in weekly CTs compared to prepandemic levels (+31.9%, p=0.008), driven by increases in cancer follow-up CTs (+56.3%, p < 0.001). In the vaccination period, cancer screening CTs did not recover to baseline (-13.5%, p=0.002) and initial cancer workup CTs doubled (+100.0%, p < 0.001). The ED experienced increased cancer-related CTs (+75.9%, p < 0.001), driven by cancer follow-up CTs (+143.2%, p < 0.001) and initial workups (+46.9%, p=0.007). The pandemic continues to impact cancer care. We observed significant declines in cancer screening CTs through the end of 2021. Concurrently, we observed a 2× increase in initial cancer workup CTs and a 2.4× increase in cancer follow-up CTs in the ED during the vaccination period, suggesting a boom of new cancers and more cancer examinations associated with emergency level acute care.

Quality assurance for non-contrast CT of the abdomen and pelvis during a period of supply chain disruption leading to iodinated contrast shortage in the emergency department setting.

Iodinated contrast media (ICM) shortage crisis due to COVID-19 lockdowns led to a need for alternate imaging protocols consisting of non-contrast computed tomography (CT) for abdominal complaints and related trauma indications in emergency department (ED) settings. This quality assurance study aims to evaluate clinical outcomes of protocol modifications during ICM shortage and identify potential imaging misdiagnosis of acute abdominal complaints and related trauma. The study included 424 ED patients with abdominal pain, falls, or motor vehicle collision (MVC)-related trauma who had non-contrast CT of the abdomen and pelvis in May 2022. We accessed the initial complaint, order indication, non-contrast CT results, any acute or incidental findings, and any follow-up imaging of the same body region with their results. We evaluated their association utilizing Chi-squared tests. We assessed sensitivity, specificity, and positive/negative predictive values using follow-up scan confirmation. Across initial complaint categories, 72.9% of cases were abdominal pain, and 37.3% received positive findings. Only 22.6% of patients had follow-up imaging. Most confirmed original reports were for abdominal pain. We also found three reports of missed findings. There were significant associations between complaint categories and initial non-contrast CT report results (P < 0.001), as well as initial complaint categories and whether the patient received follow-up imaging or not (P < 0.004). No significant associations were found between follow-up imaging results and initial report confirmation. Non-contrast CT had 94% sensitivity and 100% specificity, with positive and negative predictive values 100% and 94%, respectively. Rate of missed acute diagnoses using non-contrast CT for patients presenting to the ED with acute abdominal complaints or related trauma has been low during the recent shortage, but further investigation would be needed to verify and quantify the implications of not routinely giving oral or intravenous contrast in the ED.

Evaluation of Optic Nerve Sheath Diameter by Computerized Tomography in the Detection of Early Stage Acute Ischemic Cerebrovascular Disease

Introduction: Stroke is the leading cause of high mortality rates in the emergency department (ED). In this regard, early diagnosis and starting appropriate treatments are important. We aimed to evaluate the efficiency of the optic nerve sheath diameter (ONSD) in the detection of ischemic cerebrovascular disease on initial brain computerized tomography (CT) images of patients presented with ischemic stroke clinic to ED. Method: In this study, 375 retrospectively-evaluated patients underwent brain CT with a pre-diagnosis of cerebrovascular events, following diffusion magnetic resonance imaging (MRI) due to suspicion of ischemic stroke. Demographic findings, vital signs, Glasgow Coma Scale, National Institute of Health Stroke Scale, Modified Rankin Scale. The results of brain CT as well as diffusion magnetic resonance imaging (MRI) were noted. The measurement of ONSD was done at 3 mm behind the optic disc from both eyes from the initial brain CT of the patients. Results: In this study, 198 out of 375 patients (52.8%) were women. The mean age of patients was obtained at 67.74±13.18 years. According to diffusion MRI, 143 (38.1%) patients experienced ischemic stroke. The mean age of patients with ischemic stroke was 68.75±12.26 years, and 80 (55.9%) patients were women. The mean scores of ONSD with ischemic stroke were 5.14±0.68 and 4.79±0.6 in the control group. In the diagnosis of ischemic stroke, there was a statistically significant difference between the patient and control groups in terms of ONSD. Conclusion: In CT images of patients with ischemic stroke, ONSD values were found to increase. If ONSD measurement via brain CT correlates with physical examination and clinical signs, it can be used as an indicator in the diagnosis of early-term ischemic stroke.

Computed tomographic findings in dogs with multiple myeloma.

Computed tomography (CT) is considered the first-line imaging modality for human patients with suspected multiple myeloma (MM). Recently the diagnostic criteria for human MM have been updated. To describe and provide a baseline of the CT features and distribution of osseous lesions in dogs diagnosed with MM and to describe the change of initial osseous lesions after the start of treatment in a subset of dogs. Single-centre, retrospective, descriptive, case series. Dogs were included when they met the updated MM criteria and if a staging CT was performed at the time of diagnosis and prior to initiation of treatment. When available, change of osseous lesions was assessed on serial imaging studies. Thirteen dogs met the inclusion criteria. All dogs had involvement of the axial skeleton and 9/13 (69%) had concurrent involvement of the appendicular skeleton. Large (≥1cm), lytic, 'punched out' or expansile bony lesions and regions of permeative lysis were most common and mainly affected the vertebral column. Discrete intramedullary soft tissue attenuating lesions of the proximal appendicular skeleton were observed in 8/13 dogs (61%) and bilateral involvement of both humeri and femurs was seen in 4/9 dogs (44%). A subset of dogs underwent serial imaging and progressive replacement of the contrast-enhancing lesions with fat attenuating tissue was observed for all dogs, corresponding with clinical improvement. This case series provides a baseline knowledge of the initial and follow-up CT features in dogs diagnosed with MM based on updated criteria.

Applicability of the Edinburgh CT Criteria for Lobar Intracerebral Hemorrhage Associated with Cerebral Amyloid Angiopathy.

Based on histopathology, Edinburgh diagnostic criteria were proposed to consider anontraumatic intracerebral lobar hemorrhage (ICH) as related to cerebral amyloid angiopathy (CAA) using the initial computed tomography (CT) scan and the APOE genetic status. We aimed to externally validate the Edinburgh prediction model, excluding the APOE genotyping and based on the modified Boston criteria on the MRI for CAA diagnosis METHODS: We included patients admitted for spontaneous lobar ICH in the emergency department between 2016 and 2019 who underwent noncontrast CT scan and MRI. According to the MRI, patients were classified into the CAA group or into the non-CAA group in the case of other causes of ICH. Two neuroradiologists, blinded to the final retained diagnosis, rated each radiological feature on initial CT scan described in the Edinburgh study on initial CT scan RESULTS: A total of 102 patients were included, of whom 36were classified in the CAA group, 46in the non-CAA causes group and 20of undetermined cause (excluded from the primary analysis). The Edinburgh prediction model, including finger-like projections and subarachnoid extension showed an area under receiver operating characteristic curves (AUC) of 0.760 (95% confidence interval, CI: 0.660-0.859) for the diagnosis of CAA. The AUC reached 0.808 (95%CI: 0.714-0.901) in anew prediction model integrating athird radiologic variable: the ICH cortical involvement. Using the Boston MRI criteria as afinal assessment, we provided anew external confirmation of the radiological Edinburgh CT criteria, which are directly applicable in acute settings of spontaneous lobar ICH and further proposed an original 3‑set model considering finger-like projections, subarachnoid extension, and cortical involvement that may achieve ahigh discrimination performance.

Incidental findings involving the temporomandibular joint on computed tomography and magnetic resonance imaging.

The temporomandibular joint (TMJ) is frequently imaged in head and neck computed tomography (CT) and magnetic resonance imaging (MRI) studies. Depending on the indication for the study, an abnormality of the TMJ may be an incidental finding. These findings encompass both intra- and extra-articular disorders. They may also be related to local, regional or systemic conditions. Familiarity with these findings along with pertinent clinical information helps narrow the list of differential diagnoses. While definitive diagnosis may not be immediately apparent, a systematic approach contributes to improved discussions between clinicians and radiologists and better patient management.

The Clinical Importance of Optic Nerve Sheath Diameter in Patients with Traumatic Brain Injury: Preliminary Report

Traumatic brain injury (TBI) is a serious health problem that is related to an increased mortality. In cases of severe TBI, the prediction of prognosis is essential. The enlargement of the optic nerve sheath diameter (ONSD) shows an increased intracranial pressure and is associated with poor outcomes. In this study, we aimed to evaluate the prognostic value of ONSD in patients with severe TBI. Forty-four patients with severe TBI were retrospectively enrolled in the study. The patients were divided into two groups: survivors (n=17) and non-survivors (n=27). Baseline characteristics, clinical data, Glasgow coma scale (GCS) on hospital admission, brain computed tomography (CT) results, injury severity score (ISS), and Marshall score were recorded for all patients. ONSD was calculated at 3 mm distance from the globe, immediately below the sclera. The ONSD on the initial CT was significantly higher in non-survivors compared with survivors (6.83±1.40 vs. 6.40±1.36, p<0.05). In addition, ISS and Marshall score were significantly higher, whereas GCS was significantly lower in non-survivors. ONSD was positively correlated with Marshall score (r=0.332, p<0.05). Receiver operating characteristics analysis demonstrated that ONSD ≥6.61 had a sensitivity of 70.4% and specificity of 64.7% for predicting mortality. It was shown that ONSD ≥6.61 had a 4.3-fold increased risk for in-hospital mortality (odds ratio: 4.35; 95% confidence interval: 1.195-15.865; p<0.05). The enlargement of ONSD on initial CT was detected to be associated with increased in-hospital mortality in patients with severe TBI.