Computed Tomography Research Articles

Low Lesion Clearance Rates in Neurocysticercosis: Is It Time to Review Guidelines?

The standard treatment guidelines of neurocysticercosis have been described as per computed tomography (CT)-based studies. We aimed to prospectively study if posttreatment magnetic resonance imaging (MRI) clearance rates of neurocysticercosis were like those reported in literature using CT. A prospective observational study in newly diagnosed children with neurocysticercosis was undertaken. Children were treated with antihelminthics and steroids and followed up after 6 months. The primary objective was to study the proportion of children with single-lesion neurocysticercosis who were in radiologic resolution at 6 months and clinical remission (seizure-free for the preceding 3 months). Eighty of 128 consecutive children screened were included (single lesion, 65; multiple lesions, 15). Seventy-two children were evaluated at 6 months. Seizure recurrence was seen in 5 (6.2%). Brain MRI showed an overall clearance of lesions in 10 (14%) children. In the children with single-lesion neurocysticercosis (65), 59 were followed up at 6 months, and lesions resolved in 9 (15.3%, 95% confidence interval of 6.1-24.4). In children with single-lesion neurocysticercosis treated with antihelminthics and corticosteroids, the lesion resolution rate is only 15% at 6 months. Thus, there is a need to review old recommendations and use MRI as a standard outcome measure.

Artificial intelligence-based analysis of lower limb muscle mass and fatty degeneration in patients with knee osteoarthritis and its correlation with Knee Society Score.

Lower-limb muscle mass reduction and fatty degeneration develop in patients with knee osteoarthritis (KOA) and could affect their symptoms, satisfaction, expectation and functional activities. The Knee Society Scoring System (KSS) includes patient reported outcome measures, which is widely used to evaluate the status of knee function of KOA. This study aimed to clarify how muscle mass and fatty degeneration of the lower limb correlate with the KSS in patients with KOA. This study included 43 patients with end-stage KOA, including nine males and 34 females. Computed tomography (CT) images of the lower limb obtained for the planning of total knee arthroplasty were utilized. Ten muscle groups were segmented using our artificial-intelligence-based methods. Muscle volume was standardized by dividing by their height squared. The mean CT value for each muscle group was calculated as an index of fatty degeneration. Bivariate analysis between muscle volume or CT values and KSS was performed using Spearman's rank correlation test. Multiple regression analysis was performed, and statistical significance was set at p < 0.05. Bivariate analysis showed that the functional activity score was significantly correlated with the mean CT value of all muscle groups except the adductors and iliopsoas. Multiple regression analysis revealed that the functional activities score was significantly associated with the mean CT values of the gluteus medius and minimus muscles and the anterior and lateral compartments of the lower leg (β = 0.42, p = 0.01; β = 0.33, p = 0.038; and β = 0.37, p = 0.014, respectively). Fatty degeneration, rather than muscle mass, in the lower-limb muscles was significantly associated with functional activities score of the KSS in patients with end-stage KOA. Notably, the gluteus medius and minimus and the anterior and lateral compartments of the lower leg are important muscles associated with functional activities.

AI-Assisted Detection and Localization of Spinal Metastatic Lesions

Objectives: The integration of machine learning and radiomics in medical imaging has significantly advanced diagnostic and prognostic capabilities in healthcare. This study focuses on developing and validating an artificial intelligence (AI) model using U-Net architectures for the accurate detection and segmentation of spinal metastases from computed tomography (CT) images, addressing both osteolytic and osteoblastic lesions. Methods: Our methodology employs multiple variations of the U-Net architecture and utilizes two distinct datasets: one consisting of 115 polytrauma patients for vertebra segmentation and another comprising 38 patients with documented spinal metastases for lesion detection. Results: The model demonstrated strong performance in vertebra segmentation, achieving Dice Similarity Coefficient (DSC) values between 0.87 and 0.96. For metastasis segmentation, the model achieved a DSC of 0.71 and an F-beta score of 0.68 for lytic lesions but struggled with sclerotic lesions, obtaining a DSC of 0.61 and an F-beta score of 0.57, reflecting challenges in detecting dense, subtle bone alterations. Despite these limitations, the model successfully identified isolated metastatic lesions beyond the spine, such as in the sternum, indicating potential for broader skeletal metastasis detection. Conclusions: The study concludes that AI-based models can augment radiologists’ capabilities by providing reliable second-opinion tools, though further refinements and diverse training data are needed for optimal performance, particularly for sclerotic lesion segmentation. The annotated CT dataset produced and shared in this research serves as a valuable resource for future advancements.

Heat transfer characteristics of petroleum coke particle packed bed: An experimental and CFD simulation study

AbstractDue to the complexity of the internal pore structure of petroleum coke loose particle‐packed beds, measuring their thermal conductivity has always been a challenging problem. This work independently developed an experimental apparatus for testing the thermal conductivity of petroleum coke particle‐packed beds and constructed a forward calculation model for the heat transfer process, which was based on one‐dimensional unsteady heat transfer. Using the Sparse Nonlinear OPTimizer (SNOPT) algorithm, a mathematical relationship between the thermal conductivity λ of the coke bed, temperature T, and equivalent particle diameter dp was established through inverse modeling. Concurrently, a digital model of the petroleum coke particle packed bed was derived utilizing three‐dimensional computed tomography (CT) scanning technology, and a pore‐scale gas–solid radiation heat transfer model was formulated based on CFD simulation technology, thereby further elucidating the heat transfer mechanism within the petroleum coke particle packed bed. The research results indicate that the temperature predicted by the established thermal conductivity model aligns well with experimental data. Further CFD simulation studies demonstrate that a smaller particle size leads to a larger temperature difference between the wall and the center of the packed bed, while a higher gas velocity results in a smaller temperature difference, with a linear correlation observed between these two factors. At high temperatures, thermal radiation between particles in the porous petroleum coke‐packed bed plays a dominant role. The research outcomes can offer significant theoretical support for a profound analysis of the heat transfer behavior of petroleum coke‐packed beds within a vertical shaft calciner.

A Systematic Literature Review of Modelling Approaches to Evaluate the Cost Effectiveness of PET/CT for Therapy Response Monitoring in Oncology.

This systematic literature review addresses model-based cost-effectiveness studies for therapy response monitoring with positron emission tomography (PET) generally combined with low-dose computed tomography (CT) for various cancer types. Given the known heterogeneity in therapy response events, studies should consider patient-level modelling rather than cohort-based modelling because of its flexibility in handling these events and the time to events. This review aims to identify the modelling methods used and includes a systematic assessment of the assumptions made in the current literature. This study was conducted and reported following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement. Information sources included electronic bibliographic databases, reference lists of review articles and contact with experts in the fields of nuclear medicine, health technology assessment and health economics. Eligibility criteria included peer-reviewed scientific publications and published grey literature. Literature searches, screening and critical appraisal were conducted by two reviewers independently. The Consolidated Health Economic Evaluation Reporting Standards (CHEERS) were used to assess the methodological quality. The Bias in Economic Evaluation (ECOBIAS) checklist was used to determine the risk of bias in the included publications. The search results included 2959 publications. The number of publications included for data extraction and synthesis was ten, representing eight unique studies. These studies addressed patients with lymphoma, advanced head and neck cancers, brain tumours, non-small cell lung cancer and cervical cancer. All studies addressed response to chemotherapy. No study evaluated response to immunotherapy. Most studies positioned PET/CT as an add-on modality and one study positioned PET/CT as a replacement for conventional imaging (X-ray and contrast-enhanced CT). Three studies reported decision-tree structures, four studies reported cohort-level state-transition models and one study reported a partitioned survival model. No patient-level models were reported. The simulation horizons adopted ranged from 1 year to lifetime. Most studies reported a probabilistic analysis, whereas two studies reported a deterministic analysis only. Two studies conducted a value of information analysis. Multiple studies did not adequately discuss model-specific aspects of bias. Most importantly and regularly observed were a high risk of structural assumptions bias, limited simulation horizon bias and wrong model bias. Model-based cost-effectiveness analysis for therapy response monitoring with PET/CT was based on cohorts of patients instead of individual patients in the current literature. Therefore, the heterogeneity in therapy response events was commonly not addressed appropriately. Further research should include more advanced and patient-level modelling approaches to accurately represent the complex context of clinical practice and, therefore, to be meaningful to support decision making. This review is registered in PROSPERO, the international prospective register of systematic reviews funded by the National Institute for Health Research, with CRD42023402581.

Total arterial revascularization with RIMA-LIMA-Y configuration in patients with left subclavian artery stenosis.

Subclavian artery stenosis (SAS) occurs in 6% of patients undergoing coronary artery bypass grafting (CABG). Complications such as subclavian-coronary steal are common. Revascularization options in such cases remain debatable. In this case series, all patients with angina, had severe triple vessel disease on angiography. All tests including computed tomography (CT) angiography of neck vessels, were done as part of routine workup for CABG. The patients, all males, had a mean age of 66.5 years with three of them having hypertension and diabetes. All were ex-smokers with mean ejection fraction (EF) of 60.1%. CT angiography of neck vessels revealed that two patients had moderate to severe while one had severe left SAS and another had severe proximal left internal mammary artery (LIMA) stenosis. Total arterial revascularization was performed, with an average of 3.5 distal grafts. The LIMA graft was employed in a Y graft configuration, anastomosed to in-situ right internal mammary artery (RIMA). All patients had uneventful postoperative stay and were discharged with a mean hospital stay of 3.8 days. There were no postoperative strokes, myocardial infarction, neurological symptoms, or change in EF. At 6-month follow-up, they were asymptomatic and doing well. The RIMA-LIMA-Y configuration can be a safe, viable option in CABG for patients with left SAS. It is challenging, with re-entry and judicious utilization of the length of LIMA being of paramount importance. The importance of CT angiography of neck vessels to detect SAS cannot be under-emphasized.

Advanced Malignant Melanoma of the Vulva in a 70 years old woman

Vulvar melanoma is a rare malignant tumor of the female genital tract tend to occur in older age women and a high tendency to metastasize because the diagnosis is usually delayed (1). In this case report, we present a 70-year-old para 8 woman who presented with progressively increasing vulvar swelling of 2 years and multiple visit to health institution. Examination revealed 7cm diameter multi-nodular mass with areas of dark and dark blue-violet color filling the introitus that involves the clitoris, labia minora, lower third of the anterior vagina and urethra. Incisional biopsy from the mass showed malignant melanoma. Imaging with CT scan revealed bilateral lung metastasis. Palliative chemotherapy was planned but the patient lost to follow up.

Development of an ultrasound-based clinical decision rule to rule-out diverticulitis

The concern for diverticulitis often leads to the use of computed tomography (CT) scans for diagnosis. We aim to develop an ultrasound-based clinical decision rule (CDR) to confidently rule-out the disease without requiring a CT scan. We analyzed data from a prospective study of adult emergency department (ED) patients with suspected diverticulitis who underwent both bedside ultrasound (US) and CT. Patient history, physical examination, laboratory findings, and US results were used to create a CDR via a recursive partitioning model designed to prioritize sensitivity, with a loss matrix heavily penalizing false negatives. We calculated the test characteristics for this CDR (TICS-Rule) and assessed the potential reduction in CT scans and ED length of stay. Data from 149 patients (84 female; mean age 58 ± 16) were used to develop the TICS-Rule. The final model integrates US diagnosis of simple and complicated diverticulitis, along with variables of heart rate, age, history of diverticulosis, vomiting, and leukocytosis. Negative US results and a heart rate below 100 effectively excluded diverticulitis. The sensitivity increased from 54.5% (32.2–75.6) in the US alone to 100% (84.6–100%) for complicated diverticulitis in the model. The TICS-Rule missed no cases of complicated diverticulitis but one case of simple diverticulitis. The median time from ED greeting to US interpretation was 103 min (IQR 62–169), compared to 285 min (IQR 229–372) for CT. The TICS-Rule uses a combination of negative US and heart rate less thanQ1 100 to exclude diverticulitis without the need for a CT scan. Integration of the TICS-Rule offers a promising enhancement to clinical decision-making while reducing both CT use and ED length of stay.

Finite-element simulation of functional knee sleeves based on three-dimensional modeling of the knee joint

Knee sleeves are one of the most satisfying and widely used items of protective equipment for sports enthusiasts. Achieving an effective balance between functionality and comfort is a key factor in the design of knee sleeves. However, there are still some problems with the knee protection products currently on the market, such as poor thermal and moisture comfort, difficulty in putting on and taking off, slippage during doing sports, and the lack of a timely and effective feedback mechanism that cannot guide the user to actively adjust their movement posture to avoid sports injuries. To improve the function and pressure comfort of the human body after wearing knee sleeves, this study took the knee joint as the research object, established a three-dimensional knee joint model through computed tomography (CT) scanning and Mimics software, and then built a finite-element model under the contact state between the human body and pressure clothing on this basis. Moreover, ABAQUS was used for finite-element simulation to obtain the pressure and displacement distribution of knee joints after wearing knee sleeves. In order to further investigate the stress state and deformation trend of knee joint after wearing knee sleeves, each section of the human body at the knee joint was divided into four regions according to the angle, and the functional relationship between pressure and displacement was obtained by curve fitting. This study has significance for the investigation of the pressure comfort threshold of knee sleeves and the optimization of the design of functional knee sleeves.

Bilateral Dermoid Ovarian Cysts in a Young Woman - A Case Report and Literature Review.

Ovarian tumors are a common type of neoplasm in women, with mature cystic teratomas being the most frequent variant. These tumors occur bilaterally in approximately 10% of cases. However, bilateral and multiple occurrences are rarely reported. A 22-year-old nulliparous woman presented with amenorrhea and sudden, generalized, dull lower abdominal pain. Diagnostic imaging, including ultrasound and computed tomography (CT) scans, revealed large solid-cystic lesions in both ovaries, with internal hyperechoic foci consistent with fat and calcification, along with thin internal septations. A laparoscopic cystectomy was successfully performed, preserving ovarian function. Histopathological examination confirmed the presence of stratified keratinized squamous epithelium, sebaceous glands, hair follicles, mature adipose tissue, blood vessels, and lymphatic vessels within the resected cysts, with no evidence of malignancy. This unique case provides valuable insights into the understanding and management of bilateral dermoid cysts, highlighting the importance of preserving ovarian function in young women.

Evaluating process parameters of SLS part of polyamide-12 recycled powder using RSM

Abstract Selective laser sintering (SLS) is a highly flexible rapid prototyping (RP) technology which can use a wide range of powdered materials to generate high quality complex geometries directly from digital models. The SLS process uses a laser to sinter selected areas of powdered materials to produce solid objects layer by layer, according to the 2D data obtained from CT scan or MRI imaging techniques. This paper presents research work for evaluating the effect of process parameters on impact toughness and surface roughness of the part manufactured on Farsoon SS402P SLS from recycled ageing FS 3300PA which is PA-12 based powder and standard operating parameters using Response Surface Methodology (RSM) design of experiments. Impact tests have been performed as per the ASTM D6110 standard using recommendations from ISO 179-2. According to the results, effect of process parameters are successfully analyzed by employing impact toughness and surface roughness tests. Based on the results of the ANOVA analysis, impact toughness increases with increasing laser power (4.467 j/cm2 at 72.5 watts). Similarly, it is also clear from the results that the region with the lowest laser power, high layer thickness, and 90-degree orientation had the lowest surface roughness (3.46 μm).

November 2024 Medical Image of the Month: A Case of Short Telomeres

No abstract available. Article truncated after 150 words. A 50-year-old woman was referred to our institution for further evaluation of her ILD. Her history of present illness began during the COVID-19 pandemic, when she noticed that she had trouble climbing stairs while wearing a mask. She also had a slowly progressive cough which, at first, she attributed to seasonal allergies. Eventually her symptoms prompted pulmonary function testing at an outside institution, which showed moderately severe restriction with a DLco 40% of predicted. Chest x-ray (Figure 1) and chest CT (Figure 2) demonstrated findings of pulmonary fibrosis. The patient worked as an accountant and was a life-long nonsmoker. No concerning exposure history and no history of any medications associated with pulmonary fibrosis. Her family history is remarkable for a brother diagnosed with IPF at age 49, currently status post lung transplant. Her sister and father were both diagnosed with alpha-1-antitrypsin (both died in their 50’s). The patient also reports …

Direct visualization of microwires in hybrid depth electrodes using high-resolution photon-counting CT.

Hybrid depth electrodes are increasingly being used for epilepsy monitoring and human neurophysiology research. Microwires extending from the tip of the Behnke-Fried (BF) electrode into (sub)cortical areas allow to isolate single neurons and perform microstimulation. Conventional CT or MRI visualize the entire microwire bundle as an artifact extending from the BF electrode tip with low resolution, without proper identification of individual microwires. We illustrate the first direct visualization method of individual microwires using high-resolution photon-counting CT (PCCT). Coregistration of the PCCT scan with a preoperative MRI can visualize individual wires directly in cortex, which is an advantage as it provides feedback on the accuracy of the implantation method and can guide future implantations. This PCCT technique allows for accurately depicting individual microwires which could be relevant for neuroscientific research through improved visualization and implantation of specific cortical and subcortical brain areas. PLAIN LANGUAGE SUMMARY: Researchers are using hybrid depth electrodes to study epilepsy and brain activity. These electrodes, called Behnke-Fried (BF) electrodes, have microwires at the tip that can record single neurons and stimulate brain areas. Regular CT or MRI scans do not show the individual microwires clearly. The authors use a new high-resolution photon-counting CT (PCCT) technique, which can show each individual microwire in the brain. By combining PCCT with MRI, the authors can precisely see where the microwires are located. This could improve future implantation surgeries and brain research.

Gender differences in correlation of biochemical parameters with the severity of COVID pneumonia and the need for oxygen/mechanical support

Background:COVID-19 pandemic had caused a global medical, economic and social problems. High infection rate, heterogenous presentation, lack of previous data and no standardized treatment had led to a need for further analysis, in order to be prepared for any potential new pandemics. We analyzed any possible correlation between gender, laboratory findings and severity of disease with need for oxygen or mechanical ventilation support. Methods: 100 patients with confirmed SARS-CoV-2 virus infection enrolled. Baseline characteristics that included age, sex, smoking history, BMI, oxygen therapy or mechanical ventilation support need were recorded. Type and severity of radiological finding determined by chest CT scan. Results: Majority of our patients were over 61 years old (58.6%), male (57.6%), and had severe radiological finding (bilateral pneumonia 29.3%, ARDS 35.4%), with only 20.2% had not required any oxygen supplementation. Regarding gender and laboratory findings, men have shown statistically significant higher values of CRP, lymphocytes, LDH and ferritin (96.4 vs 87.1, p=0.014; 1.17 vs 0.84, p=0.048; 674.8 vs 609.1, p=0.031; 1263 vs 578.4, p=0.001, respectfully). Severe radiological finding had shown positive correlation with the need for HFNC and/or (N)IMV (p=0.021 and p=0.032. respectfully), as well as with higher values of WBC, LDH and ferritin (p=0.042, p=0.035 and p=0.017. respectfully). Conclusions: There is a difference between presentation of the disease, as well as analyzed laboratory markers between sexes. The difference is most likely multifactorial and should require further research in order to discover other risk and prognostic factors.

3D-printed brachytherapy in patients with cervical cancer: improving efficacy and safety outcomes

ObjectiveThis study aims to evaluate the efficacy and safety of 3D printing technology in brachytherapy for cervical cancer, comparing its outcomes with conventional free hand implantation brachytherapy.MethodsA total of 50 cervical cancer patients treated at the First Affiliated Hospital of Gannan Medical College from January 2019 to July 2023 were included in this study. Patients were divided into two groups: 25 patients received intensity-modulated radiotherapy (IMRT) combined with 3D-printed brachytherapy, and 25 patients underwent IMRT combined with free hand brachytherapy implantation. Key indicators analyzed included short-term therapeutic effects, survival outcomes, operation times, the number of CT scans, the number of needles inserted, dosimetric parameters, and complications.ResultsThe use of 3D-printed brachytherapy significantly improved the safety of radiation therapy operations, especially for large tumors (≥ 30 mm), by providing more precise dose distribution and reducing the radiation doses received by critical organs such as the bladder and rectum. Compared to the artificial implant group (88% prevalence), the 3D-printed brachytherapy group showed a significantly lower incidence of radiation enteritis (29.2% prevalence, p < 0.001). There were no significant differences in other complications between the two groups. For instance, the incidence of radiation cystitis was relatively high in the 3D-printed brachytherapy group (79.2% prevalence) compared to the artificial implant group (64% prevalence, p = 0.240). The median follow-up period in this study was 22.5 months [IQR 18–29]. Among the 49 patients included, 43 had cervical squamous carcinoma and 6 had cervical adenocarcinoma. Short-term therapeutic response rates were comparable, with no significant difference in overall survival observed between the two groups.Conclusion3D-printed brachytherapy offers a more effective and safer therapeutic option for patients with cervical cancer, particularly for those with large tumors or complex anatomical structures.

Integrating myocardial CT perfusion with coronary CT angiography improves risk stratification in patients with dialysis-dependent end-stage renal disease.

Risk stratification for incidence of major adverse cardiovascular events (MACE) in patients with dialysis-dependent end-stage renal disease (dd-ESRD) is challenging. Moreover, the usefulness of coronary CT angiography (CCTA) is often limited because of high calcification. This study aimed to investigate the prognostic value of comprehensive cardiac CT in patients with dd-ESRD for predicting MACE. This retrospective analysis included 92 patients with dd-ESRD who underwent comprehensive cardiac CT.Obstructive coronary artery disease (CAD) was defined by CCTA with > 50% stenosis. Global myocardial blood flow (MBF) and summed stress score (SSS) were obtained through dynamic CTP. Cox regression analysis was used to assess correlation with MACE. Kaplan-Meier curves were used to estimate cumulative event rates, and the global Chi-square test was used to assess the incremental value of dynamic CTP over CCTA. During a median follow-up of 2.3years, 43 patients experienced MACE. Univariate analysis revealed that presence of obstructive CAD, higher SSS, and lower global MBF were significantly associated with increased risk of MACE. In multivariable analysis, lower global MBF and presence of obstructive CAD were independently associated with MACE (p = 0.02, and p = 0.04, respectively). CCTA and dynamic CTP combination had incremental value over CCTA alone for predicting MACE, respectively (global Chi-square score, 19.3 and 11.7, respectively). Presence of obstructive CAD on CCTA and lower global MBF on dynamic CTP are independently associated with increased risk of MACE in patients with dd-ESRD. The addition of dynamic CTP to CCTA may improve risk stratification in this population.

The fallacy of a roadmap computed tomography after an abdominal gunshot wound: A road that leads to nowhere.

The 2019 Western Trauma Association guidelines recommend an abdominopelvic computed tomography (CTAP) in patients with a question of abdominal penetration after a gunshot wound. However, it is common practice to obtain a CTAP to provide a roadmap for an operation or to potentially alter management even in patients with classic indications for a laparotomy. The hypothesis for this study was that a CTAP for preoperative planning has no value in patients with an abdominal gunshot wound. This was a retrospective study from 2017 to 2022 of patients with an abdominal gunshot wound who had a preoperative CTAP. Data collection included clinical characteristics and CTAP and operative findings. Admission hypotension, abdominal pain and/or peritonitis, evisceration, and a transabdominal trajectory were considered clear indications for laparotomy. Computed tomography and operative findings were compared to determine concordance and if computed tomography altered management. There were 149 patients included in the study, of which 72.5% had a clear indication for laparotomy. The CTAP findings were concordant with operative findings in 57.0% of patients, while additional injuries were found at laparotomy in 36.2% of patients. Based on CTAP, a negative diagnostic angiogram was performed in three patients (2.0%). Three patients (2.0%) underwent a trial of nonoperative management based on CTAP findings. All underwent laparotomy after a clinical change. Six patients (4.0%) had a nontherapeutic operation; all patients had findings suspicious for either a hollow viscous injury or a vascular injury on preoperative imaging. While a CTAP scan may help to define an intra-abdominal trajectory when the trajectory is unclear, it does not alter management in those with indications for operation. In addition, CTAP missed injuries in a third of patients and contributed to all six nontherapeutic laparotomies. A preoperative CTAP has minimal value in patients who have indications for an operation. Diagnostic Test/Criteria; Level IV.

Comparison of Hemorrhage on CT Versus MRI After Thrombectomy: The HECATE Study

Background The characterization of hemorrhage following acute stroke intervention has largely been computed tomography (CT) based. We sought to compare magnetic resonance imaging‐ (MRI‐) and CT‐based scoring of hemorrhage after acute endovascular therapy (EVT) applying the Heidelberg Bleeding Classification (HBC) to assess intermodal agreement and quantify interrater agreement. Methods Consecutive patients with acute stroke were included in this retrospective study if they (1) had MRI and CT ≤12 hours of each other OR (2) had CT bracketed by MRI pre‐ and post‐CT (ie, MRI‐CT‐MRI) ≤7 days post‐EVT. The concordance of the HBC ratings by consensus panel were compared between CT and T2 * gradient recalled echo MRI. Results For the 87 EVT‐treated patients included, median age was 68 years [60–74], admission National Institutes of Health Stroke Scale score 18 [13–23], 47% were treated with intravenous/intraarterial thrombolytics, and 93% were successfully recanalized (modified Thrombolysis in Cerebral Infarction 2b/3). Hemorrhage was detected on at least 1 modality in 60% (52/87) of patients. We found a 68% (59/87, 95% CI [57%–77%]) agreement overall between CT and MRI for hemorrhage classification post‐EVT. MRI had the best interrater agreement for HBC 0 (no hemorrhage) with excellent concordance (ĸ = 0.882), compared with CT (ĸ = 0.683). T2 * gradient recalled echo MRI tended to have increased sensitivity to scattered petechial hemorrhage (HBC 1a) as compared with CT with 17% (2/12) intermodal agreement. The interrater agreement of HBC class 2 (ie, parenchymal hematoma grade 2 was substantial for MRI (ĸ = 0.781) and excellent in CT (ĸ = 0.951), with 67% (8/12) intermodal agreement. Subarachnoid hemorrhage was detected in 24% (21/87) of patients on CT and/or MRI with 29% (6/21) intermodal agreement. Conclusion With the exception of subarachnoid hemorrhage and minor petechial hemorrhagic transformation, we found that MRI and CT are overall interchangeable for detecting and classifying hemorrhage after EVT. These findings are reassuring for both clinical decision‐making and research application. Given the complexity of hemorrhage subtypes post‐EVT, work to further refine a post‐EVT hemorrhage classification scale with clinical correlation would be beneficial.

Meta-analysis study on anesthetic sedation recovery and onset times in pediatric and elderly patients undergoing CT and MRI.

Computed Tomography (CT) and Magnetic Resonance Imaging (MRI) are crucial diagnostic modalities that require patients to remain immobile for extended periods, with anesthesia sometimes used for comfort and image quality enhancement. The study compares dexmedetomidine and propofol in reducing recovery time and sedation onset in pediatric and elderly patients undergoing CT and MRI procedures. A meta-analysis of fifteen studies assessing recovery time, sedation onset, and failed sedation between dexmedetomidine and propofol in pediatric and elderly patients during CT and MRI was conducted. The study indicated that the administration of anaesthesia markedly improved patient compliance and reduced motion artefacts in both CT and MRI (P<0.00001, I2=94%). The meta-analysis indicated that the mean difference (MD) in the onset of sedation was significantly faster in the control group (P<0.00001, I2=96%). The study reveals that dexmedetomidine and propofol anesthesia can improve patient image quality during CT and MRI procedures by reducing motion artefacts. Dexmedetomidine sedated people more quickly than propofol, but no significant differences in sedation duration were observed.

Diagnostic value of CT in patients with stable chronic obstructive pulmonary disease at high altitude: Observational study.

This research aims to explore the diagnostic value of computed tomography (CT) indicators in patients with stable chronic obstructive pulmonary disease (COPD) in a plateau of China, and to find out the correlation between CT indexes and lung function and symptoms. This study screened out 53 stable COPD patients and 53 healthy people through inclusion and exclusion criteria in Hongyuan county, Aba Prefecture, Sichuan Province, between July 2020 and December 2020, and then collected their baseline data, conducted lung function tests and chest CT scans, and collected COPD Assessment Test (CAT), modified Medical Research Council Dyspnea Scale (mMRC) scores. The CT indexes of the 2 groups were compared, binary logistic regression was used to analyze the influence of COPD, the receiver operating characteristic (ROC) curve was used to evaluate the diagnostic value of the CT indexes for COPD. The Spearman test was used to understand the correlation analysis between the CT indexes and lung function, symptom score, and the number of acute exacerbations. Multiple linear regression was used to analyze the influencing factors of lung function. The percentage of low-attenuation areas less than -950 Hounsfield units (%LAA-950; t = -4.387,P = 0), percentage of wall area (WA%; t = -4.501, P = 0), and thickness-diameter ratio (TDR; t = -4.779, P = 0) in the COPD group were higher than those in the normal group. ROC shows that: %LAA-950 (P = .047) and TDR (P = .034) were independent influence in COPD in the plateau. %LAA-950 combined with TDR (AUC = 0.757, P < .001) had the value of diagnosis of COPD in the plateau. All 3 indexes are negatively correlated with lung function, and positively correlated with the symptoms and the number of acute exacerbations. Multiple linear regression analysis showed that the main factors for decrease of ratio of measurement to prediction of forced expiratory volume to the first second (FEV1%) included %LAA-950 (OR = -0.449, P < .001) and WA% (OR = -0.516, P < .001). CT indexes have a certain diagnostic value in patients with stable COPD at high altitude.