Normal 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.

The effect of retroaortic left renal vein on lumbar osteophytes formation

PurposeAssess whether a Retroaortic left renal vein (RLRV) affects vertebral osteophyte formation in the lumbar spine, compared to normal anatomy left renal vein. MethodsWe conducted a retrospective case-control study. Computed tomography (CT) scans of individuals with a RLRV (study group) were compared to age- and gender-matched normal anatomy CT scans (control group).L1 to L4 vertebral levels were appreciated for: left renal vein level, osteophyte presence and the aorta-vertebral distance (AVD) at the left renal vein level.Univariate analyses were conducted using Chi-square test and Fisher's test for categorical variables, and Student's t-test for continuous variables. Logistic regression was used for multivariate analyses. ResultsA total of 240 patients were included in the study - equally distributed between the study and control groups.Normal anatomy left renal veins traversed the spine only at the L1 and L2 levels. RLRVs traversed the spine in all L1-L4 levels, mostly at the L3 and L2.Osteophyte prevalence at the level of left renal vein was significantly higher in the study group, compared with the control group [OR 2.54, P = 0.01].Mean AVD was greater in the study group [9.2 mm ±3.6 mm Vs. 3.5 mm ± 2.6 mm, P < 0.001].Increased AVD was found to be associated with a higher chance of osteophyte presence at the level of the left renal vein [OR 1.282, P = 0.025]. ConclusionsOsteophytes are more prevalent at the level of the RLRV variant compared to the normal anatomy. Furthermore, the RLRV is characterized by a lower lumbar level compared to the normal anatomy. Clinical relevance statementThis anatomic variation could assist in further understanding of osteophyte formation.

Congenital Unilateral Hearing Loss from Cochlear Nerve Canal Stenosis

A 2-month-old baby girl presented with a failed neonatal otoacoustic emission (OAE) hearing screening in the left ear. Combined Auditory Brainstem Response/Auditory Steady-State Response (ABR/ASSR) testing confirmed the presence of a unilateral left moderate to severe hearing loss. No Joint Committee on Infant Hearing (JCIH) risk factors for early childhood hearing loss1 were identified. She subsequently underwent computed tomography (CT) of the temporal bones to determine the presence of any inner ear malformation. No abnormalities of the internal auditory canal, cochlea, semicircular canals and ossicles were noted by the radiologist, and the study was officially reported as a “normal temporal bone CT scan.” Independent review of the CT imaging revealed the presence of a visually apparent disparity in the width of the cochlear nerve canals. (Figure 1) Measurement of the cochlear nerve canal width in the axial plane parallel to the infraorbitomeatal line2 using the length measurement tool in the DICOM imaging software (RadiAnt DICOM Viewer, Version 2024.1, Medixant) indicated a cochlear nerve canal width of 2.18 mm on the right and 1.02 mm on the left. (Figure 2) Applying the suggested cutoff point of 1.2 mm as described by Lin et al.,2 we identified the presence of left cochlear nerve canal stenosis as the etiology of the congenital unilateral hearing loss. The cochlear nerve canal, which has also been referred to as the bony canal for the cochlear nerve (BCNC), cochlear aperture, and cochlear fosette, is the bony transition point between the internal auditory canal and the cochlear modiolus. A relationship between a hypoplastic cochlear nerve canal and congenital sensorineural hearing loss was first suggested by Fatterpekar et al. in 2000.3 Subsequent studies confirmed the association between cochlear nerve canal stenosis and sensorineural hearing loss that ranges from near-normal to profound, with a statistically significant relationship between the degree of hearing loss and the degree of stenosis.4 Various cutoff points to define stenosis of the cochlear nerve canal have been identified in the medical literature. These cutoff points range from 1.2 mm to 1.7 mm when the canal width is measured in the axial plane.2 This particular case demonstrated clear-cut evidence of cochlear nerve canal stenosis, as it satisfied the smallest cutoff criteria (&lt; 1.2 mm) seen in the medical literature. The identification of cochlear nerve canal stenosis as the cause of congenital sensorineural hearing loss is important not only from a diagnostic point, but also from a prognostic perspective. Cochlear nerve deficiency has been noted to be highly prevalent among pediatric patients with cochlear nerve canal stenosis,5 and this has significant negative implications in relation to rehabilitation with external hearing devices and cochlear implants.

Early Discharge versus 6-hour Observation in Mild Traumatic Brain Injury with Normal Brain CT Scan; a Comparative Pilot study of Outcomes.

Early discharge from the emergency department (ED) or a 6-hour observation in the ED are two methods for management of patients with mild traumatic brain injury (mTBI) with normal brain computed tomography (CT) scan. This study aimed to compare the outcomes of the two management options. This study is a single-center, open-label, pilot randomized case control study conducted in the ED of Ramathibodi Hospital from June 2022 to September 2023. Eligible participants included all individuals with mTBI who had negative findings on Brain CT scans. They were randomly assigned to either the early ED discharge or 6-hour ED observation group and compared regarding the outcomes (rate of 48-hour ED revisits; occurrence of post-concussion syndrome (PCS) 1 day, 1 month, and 3 months after the initial injury; and 3-month mortality). 122 patients with the mean age of 74.62 ± 14.96 (range: 25-99) years were consecutively enrolled (57.37% female). No significant differences were observed between the early discharge and observation groups regarding the severity of TBI (p=0.853), age (p=0.334), gender (p=0.588), triage level (p=0.456), Glasgow Coma Scale (GCS) score (p=0.806), comorbidities (p=0.768), medication usage (p=0.548), mechanism of injury (p=0.920), indication for brain CT scan (p=0.593), time from TBI onset to ED arrival (p=0.886), and time from ED triage to brain CT scan (p=0.333). Within 48 hours after randomization, the incidence of revisits was similar between the two groups (1.57% vs. 3.23%; p = 1.000). There were no statistically significant differences in the incidence of PCS between the early discharge and observation groups at 1 day (33.90% vs. 35.48%, p = 0.503), at 1 month (12.07% vs. 13.11%, p = 0.542), and at 3 months (1.92% vs. 5.56%, p = 0.323) after randomization. After a three-month follow-up period, four patients in the early discharge group, had expired (none of the deaths were associated with TBI). It seems that, in mTBI patients with normal initial brain CT scan and the absence of other injuries or neurological abnormalities, early discharge from the ED without requiring observation could be considered safe.

Classification and Characterization of Traumatic Brain Injuries in the Northern Region of Sweden.

Traumatic brain injury (TBI) is a common cause of death and disability, the incidence of which in northern Sweden is not fully investigated. This study classifies and characterize epidemiological and demographic features of TBIs in a defined population in Umeå county, Sweden. Specifically, to evaluate frequencies of (1) intracranial lesions detected with computed tomography (CT), (2) need for emergency intervention, and (3) hospital admission, in minimal, mild, moderate, and severe TBI, respectively. The data were gathered from 4057 TBI patients visiting our emergency room (ER) during a two-year period (2015-2016), of whom 56% were men and approximately 95% had minimal TBIs (Glasgow Coma Scale (GCS), score 15). Of all injuries, 97.8% were mild (GCS 14-15), 1.7% were moderate (GCS 9-13), and 0.5% were severe (GCS < 9). CT scans were performed on 46% of the patients, with 28% being hospitalized. A high annual TBI incidence of 1350 cases per 100,000 citizens was found. The mortality rate was 0.5% with the majority as expected in the elderly group (>80 years). Minimal TBIs were not as mild as previously reported, with a relatively high frequency of abnormal CT findings and a high mortality rate. No emergency intervention was required in patients in the GCS 13-15 group with normal CT scans. These findings have implications for clinical practice in the ER with the suggestion to include biomarkers to reduce unnecessary CT scans.

Multiple radiologist review of adrenal CT still frequently misses lateralized surgical primary aldosteronism.

Patients with primary aldosteronism (PA) have increased morbidity and mortality compared to those with essential hypertension. Accurate detection of lateralized PA is important so that affected patients can receive potentially curative adrenalectomy. However, around 40% of patients with lateralized PA have "normal" adrenal glands on computed tomography (CT). Additional independent review of imaging has been shown to improve diagnostic accuracy in many areas of imaging. Therefore, the authors sought to establish if multi-reader re-assessment of previously reported normal CT scans would result in increased detection of surgically remediable disease. The authors found that re-assessment of CT imaging by one, two, or three additional radiologists (or a combination thereof) slightly increased the detection of lateralized disease, but these differences were not statistically significant (p>.05). Readers had low inter-observer agreement (kappa=0.17). If detection of a discrete nodule on CT was made a prerequisite for adrenal vein sampling (AVS), a second read by another reviewer would still result in an excess of missed cases (84.2%, 36.8%, and 65.8%, respectively, for each of the three independent reviewers). Therefore, a "normal" CT does not preclude the possibility of lateralized PA. Adrenal vein sampling should still be strongly considered wherever available and whenever surgery is considered for treatment of PA, irrespective of CT findings.

Full Body Screening Computed Tomography Prior to Allogeneic Hematopoietic Stem Cell Transplantation: A Single Institution Experience from an Academic Center

Background: The extent of pretransplant workup for allogeneic hematopoietic stem cell transplant (HSCT) differs considerably among transplant centers. Current practice at the University of Wisconsin is for all recipients to undergo screening CT (computed tomography) of the sinuses, chest, abdomen, and pelvis prior to HSCT which can reveal several incidental radiographic findings. Here, we examined the impact of this procedure on discovery of clinically meaningful incidental findings, on time to transplant, on detecting post-COVID-19 infection related complications and on overall clinical outcomes post-HSCT in the current era of novel treatments for malignant hematologic disorders. Methods: After IRB approval, all consecutive patients &amp;gt; age 18 years at the University of Wisconsin who underwent full body screening CT prior to HSCT, from January 2019 to August 2022 were studied. Imaging abnormalities were defined as any finding reported by the radiologist apart from isolated mucosal thickening on sinus CT scans. Post-transplant pulmonary complications were defined as abnormal chest CT scans within 6 months post-transplant. Patient and disease characteristics were tabulated, and descriptive statistics are reported. Progression free survival (PFS) is defined as the time from transplant to first identification of relapsed disease. Results: Table 1 shows clinical characteristics of the study cohort. Median follow up is 22.55 months (95% CI 12.04-34.78). A total of 205 patients underwent 577 screening CT scans prior to HSCT, of which 82% (n=169) had at least one abnormal finding and 52% (n=107) had an incidental finding. Of the patients with incidental findings, 53% (n=57) received no additional workup or intervention while 47% (n=50) underwent further workup, yet only 18% (n=19) had a change in management as depicted in figure 2. Therapeutic interventions included treatment with antifungals (n=11), antibiotics (n=5), thoracentesis (n=1), thoracotomy (n=1) and anticoagulation (n=1). Although 50% of all chest CT scans identified an abnormality, only 5% revealed an incidental finding that influenced management including pulmonary nodules (n=7), bronchiolitis (n=1) and pulmonary emboli (n=1), compared to just 3% for both sinus and abdominal CT scans including sinusitis (n=4), periapical abscesses (n=3) and abdominopelvic masses of the bladder (n=1), iliac fossa (n=1), pancreas (n=1) and ovary (n=1). Post-HSCT complications were identified in 23% (n=21) vs 16% (n=15) in those with abnormal and normal pre-HSCT chest CT, respectively. In the subset of patients who underwent therapeutic interventions resulting from abnormal screening chest CT, 28% (n=5) still experienced post-transplant complications. Finally, the incidence of post-transplant pulmonary complications was similar, 27% (n=4), in patients with and without documented COVID infection prior to transplant. Median time to HSCT after scan completion was similar in patients with normal vs abnormal imaging without additional workup at 23 days (range 11-47), compared to 24 days (range 8-62), respectively. In contrast, median time to HSCT was longer at 30 days (range 11-173) and 48 days (range 13-208) for those who received additional work up and a therapeutic intervention, respectively (p=0.0001). One year post HSCT non-relapse mortality was 9% and 12 % among patients with normal screening CT, and those with at least one abnormal finding, respectively. 2-year PFS was similar in patients with abnormal vs normal screening chest CT scans at 60% vs 58% respectively (p=0.98). Conclusions: We observed high rates of incidental findings leading to additional work up in over 40% of patients, though less than half of them led to changes in management. As expected, we noted a substantial risk of delay to HSCT in most recipients needing intervention. Chest CT scans had the highest prevalence of clinically significant incidental findings and meaningful impact on management, whereas routine sinus and abdomen-pelvic CT showed lower clinical benefit. No additional advantage of CT chest was found in asymptomatic patients who had a COVID-19 infection pre-HSCT. Our findings provide basis to re-evaluate current practice of pre HSCT screening, and identify at-risk patients who would benefit from screening. Additional analyses are needed to minimize risks of unnecessary interventions, delays and burden on patients and healthcare utilization.

Computerized Tomography Scan Findings in Pediatric Patients with Coronavirus Disease 2019

Background: This study aimed to ascertain the computerized tomography findings of 56 children diagnosed with coronavirus disease 2019 (COVID-19) at Ali Ibn Abitalib Hospital in Zahedan, Iran. Methods: This descriptive, cross-sectional study was conducted on 56 pediatric patients with laboratory-confirmed COVID-19 who were treated at Ali Ibn Abitalib Hospital in Zahedan from March to August 2020. The computerized tomography (CT) scans were performed for these children because they did not show signs of improvement, had decreased oxygen levels during the treatment, had severe respiratory symptoms, or had a breathing disorder. The CT findings were reviewed to determine the frequency of normal and abnormal scans. The distribution of lesions (unilateral, bilateral, peripheral, central), type of opacity (consolidation, ground glass, etc.), and presence or absence of bronchiectasis, effusion, cavity, and lymphadenopathy were recorded. The frequency of each type of lesion was then calculated. Results: Of the patients, 30.36% had a normal CT scan. The most common CT scan finding was ground-glass opacity (42.86%), followed by consolidation (35.71%). The distribution of lesions was mostly bilateral (64.10%) and mainly peripheral (66.67%). Conclusions: One-third of children with COVID-19 had normal CT features. Ground-glass opacity and consolidation were more common than cavity or pneumatocele, pleural effusion, bronchiectasis, and lymphadenopathy.

Intensive Care Physician-Led Clearance of the Cervical Spine: A Retrospective Review of the Utility of a Normal Cervical CT Scan for Safe Removal of Hard Collars by Critical Care Physicians.

Background: Cervical spine clearance in intubated patients due to blunt trauma remains contentious. Accumulating evidence suggests that a normal computed tomography (CT) cervical spine can be used to clear the cervical spine and remove the collar in unconscious patients presenting to the emergency department. However, whether this strategy can safely be employed by critical care physicians with intubated patients admitted to the trauma intensive care unit (TICU) with cervical collars in situ, has not been definitively studied. Methods: A retrospective review of 730 intubated victims of trauma who presented to the Level 1 Trauma center of a tertiary hospital was conducted. The rates of missed cervical injuries in patients who had their cervical collars removed by intensive care physicians based on a normal CT scan of the cervical spine, were reviewed. Secondary outcomes included rates of collar-related complications. Results: Three hundred and fifty patients had their cervical collars removed by Trauma ICU doctors based on a high-quality, radiologist-interpreted normal CT cervical spine. Seventy percent of patients were sedated and/or comatose at the time of collar removal. Fifty-one percent of patients had concomitant traumatic brain injury. The average GCS at time of collar removal was 9. The incidence of missed neurological injury discerned clinically at time of both ICU and hospital discharge was nil (negative predictive value 100%). The rate of collar-related complications was 2%. Conclusion: Cervical collar removal by intensive care physicians on TICU following normal CT cervical spine, is safe, provided certain quality conditions related to the CT scan are met. Not removing the collar early may be associated with increased complications. An algorithm is suggested to assist critical care decision-making in this patient cohort.

Evaluation of Cancer Risk Induced by Radiation Exposure from Normal Head CT Scans

Purpose: Radiology examinations are growing significantly every year. Analysis of the CT scan reports can highlight defects and is a good way to develop safety in healthcare. This study aimed to evaluate the rate of normal head Computed Tomography (CT) scans at a hospital radiology department in Shahroud and estimate the cancer risk associated with these normal CT scans.&#x0D; Materials and Methods: In total, the data of 400 patients referred to the emergency radiology center of Imam Hossein hospital in Shahroud from November 23 to December 10, 2021, were collected. CT scan reports were categorized into three groups according to the interpretation of the radiologist. The BEIR VII model was used to estimate the radiation cancer risk.&#x0D; Results: Among the 400 patients, 248 (62%) were males and the average age of the patients was 49.05 ± 22.60 years. CT scans in 270 (67.5%) cases were reported normal. The average age of the patients with normal, and abnormal CT scans were 41.86 ± 20.27, and 63.03 ± 20.27 years, respectively and the difference was significant (p-value &lt;0.001). The average effective dose was obtained 1.72±0.09, 1.31±0.11, and 0.87±0.09 mSv for different age groups of 1-5, 5-10, &gt;10-year-old. The average risks of all solid cancers were 7.82 cases per 100,000 patients, while the average risk of leukemia was 0.71 cases per 100,000 patients.&#x0D; Conclusion: A large percentage of CT examinations are normal in our country which leads to many public health issues in the future years. Therefore, efforts should be made to establish predictor clinical factors to reduce unnecessary radiology examinations.

Analysis of traumatic intracranial hemorrhage and delayed traumatic intracranial hemorrhage in patients with isolated head injury on anticoagulation and antiplatelet therapy.

Anticoagulants and antiplatelet (ACAP) agents are increasingly and frequently used, especially in the elderly. The present study was carried out to assess the prevalence of delayed traumatic intracranial hemorrhage (dtICH) after a normal result on an initial head computed tomography (CT) in adults who were taking ACAP medication. The present retrospective included all adult patients who arrived in the emergency department between January 2017 and January 2021 with a history of fall from the patient's own height, while being on ACAP medication with an isolated head injury. The Institutional Review Board approved the study with a waiver of consent. The primary outcome measures were prevalence of dtICH in patients who had initial normal CT scan brain and were on ACAP medication. There were 2137 patients on ACAP medication, of which 1062 were male, and 1075 were of the female gender. The mean age of the patients was 82.1 years. About 8.2% had positive first CT scans (176/2137), while 0.023 (27/1149) had dtICH. The most common positive finding on the CT scan was subarachnoid hemorrhage followed by subdural hemorrhage. Male gender positively correlated with increased risk for first CT being positive (P = 0.033). Patient's with comorbidity of cirrhosis and chemotherapy had higher risk of dtICH (P = 0.47, 0.011). There was a very low (0.023%) prevalence of dtICH. Dual therapy or Coumadin therapy made up the majority of tICH. Cirrhosis and chemotherapy were associated with the risk of a repeat CT scan being positive with an initial CT scan negative.

Thoracic CT Scan Findings in Patients with Confirmed Hematologic Malignancies Admitted to the Hospital with Acute Pulmonary Symptoms

Background: Hematologic malignancies are the fifth most common malignancies worldwide. Pulmonary symptoms are among the patient’s common complaints. Early diagnosis based on patient symptoms, laboratory testing, and imaging may lead to an appropriate therapeutic approach. Objectives: To evaluate thoracic computed tomography (CT) scan findings in known cases of hematologic malignancy with acute respiratory symptoms. Methods: A cross-sectional study was conducted on 200 patients with hematologic malignancies admitted to Khansari cancer center for acute pulmonary symptoms, from December 2019 to May 2020. Collected data included demographic data, physical examination, laboratory tests and findings of thoracic CT images. Descriptive analysis and chi-Square test were performed to analyze the data using SPSS version 20. Results: Non-Hodgkin lymphoma was the most common malignancy, accounting for 48% of total cases. The most common radiological findings included atelectasis (49%), followed by pleural effusion (42%), mediastinal lymphadenopathy (38.5%), consolidation (37%), and ground-glass opacities (33.5%). Mediastinal lymphadenopathy was more prevalent in patients diagnosed with lymphoma. Among pulmonary pathologies, pneumonia was the most prevalent disease (41.5%), followed by small airway disease (13.5%), mediastinal lymphadenopathy (12.5%), chronic pulmonary disease (6.5%), and pulmonary metastasis (6%). Normal thoracic CT scan was detected in 20% of participants. Overall assessment of clinical symptoms, laboratory tests, and imaging findings did not lead to the diagnosis of acute lung involvement in 5.5% of study participants, because complete clinical data were not available in some participants. Conclusions: Assessment of the most common thoracic imaging findings in patients diagnosed with hematologic malignancies, may help make better diagnosis and planning of a rapid therapeutic approach.

Force Transfer through the Scaphotrapeziotrapezoid (STT) Joint.

Background The scaphotrapeziotrapezoidal (STT) joint transfers forces to the proximal carpal row from the thumb and fingers. Clinically, STT joint osteoarthritis is frequently observed on plain radiographs though its role in the mechanics of the wrist joint remains unclear. Questions/Purposes Our purpose was to use a model of normal wrist types, to predict STT motion upon load. Patients and Methods Five normal computed tomography scans of a wrist type 1 and five wrist type 2 were used to model the wrist. A 200-N force was split and applied to the trapezoid and capitate to replicate forces during a knuckle pushup. The bony movement was predicted by the model as bony movement using finite element analysis. Results We found differences in force transfer through the STT joint between the two wrist types when loading the index and middle fingers. Type 1 wrists moved quantitatively more anterior-posterior, type 2 wrists moved more medially-laterally and more proximally-distally. The trapezium in type 1 wrists moved more in the coronal plane than in type 2 wrists. The trapezoid moved more from distal to proximal in a type 2 wrist, p = 0.03. Conclusion/Clinical Relevance This study found differences in motion upon loading through the STT joint between type 1 and 2 wrists. Type 2 wrists moved more radially toward the proximal scaphoid and scapholunate ligament. This study may provide a mechanical basis for degenerative configurations. By linking observed patterns of degeneration to their mechanical causes we can aid in prevention of arthritis.

The value of the optic nerve sheath diameter measured using computerized brain tomography in the evaluation of mortality status in patients admitted to the emergency department with intracranial hemorrhage

Background/Aim: The optic nerve sheath diameter (ONSD) measurement is a non-invasive method that can be obtained from computerized tomography (CT) images. It can therefore be a useful diagnostic tool in determining prognosis in the emergency department. The aim of this study was to investigate the relationship between ONSD and mortality status in patients with intracranial hemorrhage who presented to the emergency department by measuring ONSD on computerized brain tomography images taken during admission. Methods: This retrospective cohort study was carried out in the emergency department of a tertiary hospital between December 1, 2018 and December 1, 2020 and included intracranial hemorrhage patients and patients with normal brain CT scans that had been obtained for any reason. Bilateral ONSDs were measured in both the intracranial hemorrhage and control groups. We first evaluated whether ONSD would differ between the two groups after which the relationship between ONSD and mortality was analyzed in the patient group who presented with bleeding. Results: Intracranial hemorrhage was present in half the cases and midline shift in 21.5%. A statistically significant increase in ONSD was observed in cases with intracranial hemorrhage (P &lt; 0.001). Similarly, a statistically significant increase in ONSD was found in cases with midline shifts and mortality (P &lt; 0.001). A cut-off value of 4.19 mm for mean optic nerve diameter exhibited 100% sensitivity and 70% specificity in terms of hemorrhage detection (area under the curve [AUC]: 0.952; P &lt; 0.001). A cut-off value of 6.03 mm for ONSD exhibited 76% sensitivity and 74% specificity in terms of hemorrhage detection (AUC: 0.730; P = 0.001). The odds ratio for prediction of mortality based on a regression analysis was 8.838 in cases with intracranial hemorrhage (P &lt; 0.001). Conclusion: ONSSD measured on CT images is a promising tool for prediction of intracranial hemorrhage, midline shift, and mortality status.

PAM-DenseNet: A Deep Convolutional Neural Network for Computer-Aided COVID-19 Diagnosis.

Currently, several convolutional neural network (CNN)-based methods have been proposed for computer-aided COVID-19 diagnosis based on lung computed tomography (CT) scans. However, the lesions of pneumonia in CT scans have wide variations in appearances, sizes, and locations in the lung regions, and the manifestations of COVID-19 in CT scans are also similar to other types of viral pneumonia, which hinders the further improvement of CNN-based methods. Delineating infection regions manually is a solution to this issue, while excessive workload of physicians during the epidemic makes it difficult for manual delineation. In this article, we propose a CNN called dense connectivity network with parallel attention module (PAM-DenseNet), which can perform well on coarse labels without manually delineated infection regions. The parallel attention module automatically learns to strengthen informative features from both channelwise and spatialwise simultaneously, which can make the network pay more attention to the infection regions without any manual delineation. The dense connectivity structure performs feature maps reuse by introducing direct connections from previous layers to all subsequent layers, which can extract representative features from fewer CT slices. The proposed network is first trained on 3530 lung CT slices selected from 382 COVID-19 lung CT scans, 372 lung CT scans infected by other pneumonia, and 200 normal lung CT scans to obtain a pretrained model for slicewise prediction. We then apply this pretrained model to a CT scans dataset containing 94 COVID-19 CT scans, 93 other pneumonia CT scans, and 93 normal lung scans, and achieve patientwise prediction through a voting mechanism. The experimental results show that the proposed network achieves promising results with an accuracy of 94.29%, a precision of 93.75%, a sensitivity of 95.74%, and a specificity of 96.77%, which is comparable to the methods that are based on manually delineated infection regions.

Machine Vision Approach for Diagnosing Tuberculosis (TB) Based on Computerized Tomography (CT) Scan Images

Tuberculosis is curable, still the world’s second inflectional murderous disease, and ranked 13th (in 2020) by the World Health Organization on the list of leading death causes. One of the reasons for its fatality is the unavailability of modern technology and human experts for early detection. This study represents a precise and reliable machine vision-based approach for Tuberculosis detection in the lung through Symmetry CT scan images. TB spreads irregularly, which means it might not affect both lungs equally, and it might affect only some part of the lung. That’s why regions of interest (ROI’s) from TB infected and normal CT scan images of lungs were selected after pre-processing i.e., selection/cropping, grayscale image conversion, and filtration, Statistical texture features were extracted, and 30 optimized features using F (Fisher) + PA (probability of error + average correlation) + MI (mutual information) were selected for final optimization and only 6 most optimized features were selected. Several supervised learning classifiers were used to classify between normal and infected TB images. Artificial Neural Network (ANN: n class) based classifier Multi-Layer Perceptron (MLP) showed comparatively better and probably best accuracy of 99% with execution time of less than a second, followed by Random Forest 98.83%, J48 98.67%, Log it Boost 98%, AdaBoostM1 97.16% and Bayes Net 96.83%.

Mild Head Injury: Criteria for Computed Tomography Scan

Background/Objective: Mild Head Injury (MHI) is the most commontype of head trauma, and forms a majority of the injuries seen in the traumaunit (65-85%).1 This study was aimed at using previously identifiedclinical risk factors to determine which category of patients with MHIwould not need to undergo Computed Tomography (CT). This may serveas cost saving measure to patients and hospitals likewise reduce collectiveradiation dose to the population.Methodology: A retrospective study conducted at the trauma unit of ateaching hospital situated in the Cape Metropole. CT scan images of 50patients aged 14 years and above who had MHI and undergone CTexamination were retrieved from the archive. Patients’ information, clinicalhistory and resultant CT findings were collated. Clinical risk factors werecorrelated with abnormal and normal CT scan findings. Data wereanalyzed using chi-square statistic at 95% confidence interval.Results: Twenty three (46%) of the patients had abnormal CT findings,and all presented with one or more of these risk factors; severe headache(10%), skull fracture (20%), scalp injury (6%), loss of consciousness(LOC)(8%) and intoxication(2%). The results were not statisticallysignificant when compared with the normal CT scans group. Four patients(8%) with no risk factors had normal CT scans. All the patients presentingwith the clinical risk factors, of nausea and vomiting 6% (n=50), seizures4% (n=50) had normal CT scan findings.Conclusion: Certain clinical risk factors can be used to suggest theprobability of abnormal CT scan in patients with MHI. Patients with norisk factors such as patients with confusion and disorientation are morelikely to have normal CT findings and may therefore be exempted from CTexamination. Further studies with larger sample size may be helpful invalidating these findings.

Morphometry of Human Trachea in Male and Female using Computerized Tomography- A Comparative Study

Background: The architecture of the trachea can help doctors choose the right size of the endotracheal tube for patients. Non-invasive procedures like cadaveric dissection (CD) and Computed Tomography (CT) scans can also be used in the investigation. Objective: to describe the morphometry of a normal human trachea on CT scans and compare it to data from other studies Methodology: The normal CT scan pictures of 110 patients (69 males and 41 females) were analyzed in this prospective investigation. A 64-slice CT scanner was used to do chest CT scans. DICOM, a program for digital imaging and communication in medicine, was used to collect the data. For each parameter, the research population's lowest and maximum values were established. The correlation between all research variables and height and weight was determined using Pearson's correlation method. Height and weight were used as predictors in a regression analysis of substantially correlated factors. Results: In males, the AP and transverse diameters were substantially linked with height. The diameter of the AP and the CSA were found to be substantially linked with weight. A-P diameter, cross-sectional area, and volume were shown to be poorly predicted by weight. Weak predictors of length and transverse diameter were found to be height. In females, there was no association between height or weight with any of the research parameters. It was discovered that neither body mass index (BMI) nor height (or weight) could predict the dependent variables. Conclusion: The data might be valuable in the setup and design of tracheostomy tubes and endotracheal tubes in the future. Keywords: Trachea, diameters, Cross-sectional area, Volume, Computerized tomography.

Preoperative CT simulation of iliosacral screws for treating unstable posterior pelvic ring injury

BackgroundThe percutaneous iliosacral screw is a common procedure for treating pelvic posterior ring instability. Traditional X-ray fluoroscopy screw placement has the advantages of decreased bleeding and trauma, but it also has some drawbacks, such as increased radiation exposure and screw dislocation. The purpose of this study was to establish a safe, effective, and quick approach for putting iliosacral screws for the treatment of unstable posterior pelvic ring damage utilizing simulated screws based on preoperative computed tomography (CT) planning.MethodsFrom February 2019 to June 2020, we retrospectively assessed 41 patients with posterior pelvic ring instability who were treated with percutaneous iliosacral screws in our institution, and randomly separated them into two groups: conventional surgery (n = 20) and preoperative planning (n = 21). Pelvic radiographs (anteroposterior, inlet, outlet), as well as normal CT scans of the pelvis, were all taken postoperatively to confirm the screw position. After that, the screw insertion time, the radiation exposure time, and the screw misplacement rate (as assessed by postoperative CT) were all examined. Screw position grading was evaluated by Smith grading.ResultsIn the conventional surgery group, 26 screws were inserted in 20 patients, with each screw insertion taking 23.15 ± 4.19 min and 1.02 ± 0.17 min to expose to radiation. Eight of the 26 screws were misplaced (30.8%). In the preoperative planning group, 24 screws were inserted in 21 patients, with each screw taking 19.57 ± 4.05 min to implant and 0.67 ± 0.09 min to expose to radiation. One of 24 screws was misplaced (4.2%). Screw insertion time, radiation exposure time, and screw dislocation rate were all significantly reduced when preoperative planning aided iliosacral screw placement (P < 0.05).ConclusionsPreoperative CT simulation of iliosacral screws for placement planning, screw trajectory, and intraoperative screw placement is a safe way for reducing surgical time, radiation exposure, and ensuring accurate screw placement.

The Optimized Oxford Hip Skeletal Maturity System Proves Resilient to Rotational Variation.

The recently described optimized Oxford skeletal maturity system utilizes anteroposterior (AP) hip radiographs to accurately, rapidly, and reliably estimate skeletal maturity. However, in the real-world setting, significant positional variation in AP hip radiographs may influence the accuracy of optimized Oxford skeletal age estimates. We sought to evaluate the consistency of skeletal age estimations using the optimized Oxford system between differently rotated radiographs. Thirty normal computerized tomography scans of males (15 children, 9 to 15 y) and females (15 children, 8 to 14 y) were obtained retrospectively, converted into 3D reconstructions, and then used to produce simulated hip radiographs in five different rotational positions. The optimized Oxford system was applied to the 150 simulated AP hip radiographs (5 differently rotated views of 30 hips) to produce a skeletal age estimate for each. Rotational position did not have a statistically significant effect on the skeletal age (P=0.84) using 1-way repeated measures analysis of variance. Of the 5 radiographic parameters in the optimized Oxford system, only greater trochanter height showed significant rotational variation after Greenhouse-Geisser correction (F2.58, 74.68=5.98, P<0.001). However, post hoc analyses showed that the greater trochanter height obtained at the most centered position was not different from the other 4 rotational positions (P>0.05 for all). The optimized Oxford skeletal maturity system is resilient to rotational variation. Mildly to moderately rotated radiographs obtained in the modern clinical setting can be used for skeletal age estimation by this method, broadening the clinical usage of this system. Level III-diagnostic study.