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1.
Quant Imaging Med Surg ; 14(2): 1616-1635, 2024 Feb 01.
Article in English | MEDLINE | ID: mdl-38415168

ABSTRACT

Background: The high-definition standard (HD-standard) scan mode has been proven to display stents better than the standard (STND) scan mode but with more image noise. Deep learning image reconstruction (DLIR) is capable of reducing image noise. This study examined the impact of HD-standard scan mode with DLIR algorithms on stent and coronary artery image quality in coronary computed tomography angiography (CCTA) via a comparison with conventional STND scan mode and adaptive statistical iterative reconstruction-Veo (ASIR-V) algorithms. Methods: The data of 121 patients who underwent HD-standard mode scans (group A: N=47, with coronary stent) or STND mode scans (group B: N=74, without coronary stent) were retrospectively collected. All images were reconstructed with ASIR-V at a level of 50% (ASIR-V50%) and a level of 80% (ASIR-V80%) and with DLIR at medium (DLIR-M) and high (DLIR-H) levels. The noise, signal-to-noise ratio (SNR), contrast-to-noise ratio (CNR), artifact index (AI), and in-stent diameter were measured as objective evaluation parameters. Subjective assessment involved a 5-point scale for overall image quality, image noise, stent appearance, stent artifacts, vascular sharpness, and diagnostic confidence. Diagnostic confidence was evaluated based on the presence or absence of significant stenosis (≥50% lumen reduction). Both subjective and objective evaluations were conducted by two radiologists independently, with kappa and intraclass correlation statistics being used to test the interobserver agreement. Results: There were 76 evaluable stents in group A, and the DLIR-H algorithm significantly outperformed other algorithms, demonstrating the lowest noise (41.6±7.1/41.3±7.2) and AI (32.4±8.9/31.2±10.1), the highest SNR (14.6±3.5/15.0±3.5) and CNR (13.6±3.8/13.9±3.8), and the largest in-stent diameter (2.18±0.61/2.19±0.61) in representing true stent diameter (all P values <0.01), as well as the highest score in each subjective evaluation parameter. In group B, a total of 296 coronary arteries were evaluated, and the DLIR-H algorithm provided the best objective image quality, with statistically superior noise, SNR, and CNR compared with the other algorithms (all P values <0.05). Moreover, the HD-standard mode scan with DLIR provided better image quality and a lower radiation dose than did the STND mode scan with ASIR-V (P<0.01). Conclusions: HD-standard scan mode with DLIR-H improves image quality of both stents and coronary arteries on CCTA under a lower radiation dose.

2.
Polymers (Basel) ; 15(9)2023 Apr 29.
Article in English | MEDLINE | ID: mdl-37177277

ABSTRACT

The W-OH type polyurethane (W-OH) has been proven to be an economical and environmentally friendly slope protection solution for slope maintenance in Pisha sandstone areas. However, the Pisha area belongs to a typical temperate continental climate with large diurnal temperature changes in winter, spring, and autumn and freezing and thawing occurring alternately between days and nights. Under freeze-thaw cycle conditions, the effect of slope treatment largely depends on the interface shear strength between W-OH-treated Pisha sandstone and pristine sandstone. Therefore, this paper studies the interfacial shear strength and long-term durability of Bisha sandstone consolidation (W-OH-treated Pisha sandstone) and Pisha sandstone under freeze-thaw cycles. First, the effects of different W-OH concentrations and different water contents on the freeze-thaw cycle interface were studied using a direct shear test. Based on the experimental results, the W-OH material was further modified with ethylene vinyl acetate (EVA). Finally, the damaged surface of the sample was observed through an ultra-depth-of-field microscope, and the damage mechanism of the interface caused by the freeze-thaw cycles was further discussed. The experimental results show that the peak shear strength at the interface increases with the increase in W-OH concentration and decreases with the increase in freeze-thaw cycles. The cohesion at the interface generally increases with the increase in W-OH concentration and reaches a maximum value of 43.6 kPa when the W-OH concentration is 10%. At the same time, under the condition of high water content, the curing of the W-OH material has no significant effect on the bonding performance of the interface. Using EVA to modify the W-OH material can improve the freeze-thaw durability of the interface. After modification, the interfacial cohesion of the sample increases with the increase in the EVA concentration and can reach 162% of the original. Using an ultra-depth-of-field microscope, it was found that the repeated solidification-melting action of water between the interfaces makes the consolidated body on the damaged surface fall off, resulting in cracks. As the water content between the interfaces increases, the damage to the material is greater. However, the addition of EVA can fill the uncovered pores of W-OH cement, thereby improving the cohesion at the interface and effectively alleviating the freeze-thaw damage caused by the high water content at the interface. The results of this study can provide some theoretical references for slope treatment in the Pisha sandstone area using W-OH materials.

3.
Front Oncol ; 13: 1225116, 2023.
Article in English | MEDLINE | ID: mdl-38298440

ABSTRACT

Objective: To evaluate the diagnostic accuracy of fusion imaging contrast-enhanced ultrasound (FI-CEUS) of magnetic resonance imaging (MRI) LI-RADS-indeterminate (LR-3/4) and conventional ultrasound undetected focal liver lesions (FLLs) in patients at risk for hepatocellular carcinoma (HCC). Methods: Between February 2020 and July 2021, 71 FLLs in 63 patients were registered for diagnostic performance evaluation respectively for ultrasound-guided thermal ablation evaluation in this retrospective study. Diagnostic performance regarding FLLs was compared between FI-CEUS and contrast-enhanced MRI (CE-MRI). Results: For diagnostic performance evaluation, among 71 lesions in 63 patients, the diagnostic efficacy of FI-CEUS with LI-RADS was significantly higher than that of CE-MRI (P < 0.05) in both overall and hierarchical comparison (except for the group with lesion diameter ≥2 cm). For malignant lesions, the proportion of arterial phase hyperenhancement (APHE) and washout on FI-CEUS was higher than that on CE-MRI (P < 0.05). Conclusion: FI-CEUS has a high value in the precise qualitative diagnosis of small FLLs (<2 cm) of MRI LI-RADS-indeterminate diagnosis (LR-3/4) that are undetected by conventional ultrasound in patients at risk for HCC and can be a good supplementary CE-MRI diagnostic method for thermal ablation evaluation.

4.
J Stroke Cerebrovasc Dis ; 29(10): 105143, 2020 Oct.
Article in English | MEDLINE | ID: mdl-32912498

ABSTRACT

OBJECTIVE: The surgical procedure most appropriate for treating symptomatic Riles type 1A common carotid artery occlusion (CCAO) is unclear. This study compares the effects of ring-stripping retrograde endarterectomy (RSRE) and carotid artery crossover bypass (CACB) on cerebral perfusion improvement in patients with symptomatic Riles type 1A CCAO. METHODS: We conducted a retrospective analysis of symptomatic Riles type 1A CCAO patients treated at our centre. Postoperative improvements in the ipsilateral internal carotid artery (ICA) flow rate, ipsilateral cerebral blood perfusion (CBP) and the stroke recurrence rate were compared between patients who underwent RSRE and those who underwent CACB. RESULTS: A total of 20 CCAO patients were surgically treated at our centre from 2011 to 2018. Nine of these patients underwent RSRE, and eleven underwent CACB. No significant differences were identified between the groups in the ipsilateral blood flow rate of the ICA immediately after surgery and the ipsilateral-to-contralateral mean transit time ratios 1 day after surgery. However, the flow rate in the ICA was significantly higher in the RSRE group than in the CACB group 1 year after surgery (135.44 ± 19.22 ml/min vs. 116.36 ± 17.70 ml/min, p = 0.033). For CBP, the ipsilateral-to-contralateral mean transit time ratios were significantly lower in RSRE patients than in CACB patients 1 year after surgery (1.005 ± 0.052 vs. 1.064 ± 0.066, p = 0.044). In addition, the postoperative modified Rankin scale (mRS) score at the latest follow-up point (p = 0.884) and the stroke recurrence rate during the follow-up (88.9% vs. 90.9%, p > 0.999) were not significantly different between the two groups. CONCLUSIONS: Although the postoperative mRS score and the stroke recurrence rate were not significantly different between RSRE and CACB patients, compared to CACB, RSRE was better for improving the ipsilateral ICA flow rate and cerebral perfusion in symptomatic Riles type 1A CCAO patients.


Subject(s)
Blood Vessel Prosthesis Implantation , Carotid Artery, Common/surgery , Carotid Stenosis/surgery , Endarterectomy, Carotid , Aged , Blood Flow Velocity , Blood Vessel Prosthesis Implantation/adverse effects , Carotid Artery, Common/physiopathology , Carotid Artery, Internal/physiopathology , Carotid Stenosis/complications , Carotid Stenosis/physiopathology , Cerebrovascular Circulation , Comparative Effectiveness Research , Endarterectomy, Carotid/adverse effects , Female , Humans , Male , Middle Aged , Recurrence , Retrospective Studies , Stroke/etiology , Stroke/physiopathology , Treatment Outcome
5.
PLoS One ; 15(7): e0236378, 2020.
Article in English | MEDLINE | ID: mdl-32706807

ABSTRACT

BACKGROUND: To date, the missed diagnosis rate of pulmonary hypertension (PH) was high, and there has been limited development of a rapid, simple, and effective way to screen the disease. The purpose of this study is to develop a deep learning approach to achieve rapid detection of possible abnormalities in chest radiographs suggesting PH for screening patients suspected of PH. METHODS: We retrospectively collected frontal chest radiographs and the pulmonary artery systolic pressure (PASP) value measured by Doppler transthoracic echocardiography from 762 patients (357 healthy controls and 405 with PH) from three institutes in China from January 2013 to May 2019. The wohle sample comprised 762 images (641 for training, 80 for internal test, and 41 for external test). We firstly performed a 8-fold cross-validation on the 641 images selected for training (561 for pre-training, 80 for validation), then decided to tune learning rate to 0.0008 according to the best score on validation data. Finally, we used all the pre-training and validation data (561+80 = 641) to train our models (Resnet50, Xception, and Inception V3), evaluated them on internal and external test dataset to classify the images as having manifestations of PH or healthy according to the area under the receiver operating characteristic curve (AUC/ROC). After that, the three deep learning models were further used for prediction of PASP using regression algorithm. Moreover, we invited an experienced chest radiologist to classify the images in the test dataset as having PH or not, and compared the prediction accuracy performed by deep learing models with that of manual classification. RESULTS: The AUC performed by the best model (Inception V3) achieved 0.970 in the internal test, and slightly declined in the external test (0.967) when using deep learning algorithms to classify PH from normal based on chest X-rays. The mean absolute error (MAE) of the best model for prediction of PASP value was smaller in the internal test (7.45) compared to 9.95 in the external test. Manual classification of PH based on chest X-rays showed much lower AUCs compared to that performed by deep learning models both in the internal and external test. CONCLUSIONS: The present study used deep learning algorithms to classify abnormalities suggesting PH in chest radiographs with high accuracy and good generalizability. Once tested prospectively in clinical settings, the technology could provide a non-invasive and easy-to-use method to screen patients suspected of having PH.


Subject(s)
Deep Learning , Hypertension, Pulmonary/diagnostic imaging , Mass Chest X-Ray/methods , Mass Screening/methods , Radiographic Image Interpretation, Computer-Assisted/methods , Thorax/diagnostic imaging , Adult , Aged , Aged, 80 and over , China , Female , Humans , Hypertension, Pulmonary/epidemiology , Male , Middle Aged , Retrospective Studies , Thorax/pathology
6.
Br J Radiol ; 93(1112): 20200243, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32450727

ABSTRACT

OBJECTIVES: The chest CT findings that can distinguish patients with corona virus disease 2019 (COVID-19) from those with clinically suspected COVID-19 but subsequently found to be COVID-19 negative have not previously been described in detail. The purpose of this study was to determine the distinctions among patients with COVID-19 by comparing the imaging findings of patients with suspected confirmed COVID-19 and those of patients initially suspected to have COVID-19 who were ultimately negative for the disease. METHODS: 28 isolated suspected in-patients with COVID-19 were enrolled in this retrospective study from January 22, 2020 to February 6, 2020. 12 patients were confirmed to have positive severe acute respiratory syndrome corona virus 2 (SARS-CoV-2) RNA results, and 16 patients had negative results. The thin-section CT imaging findings and clinical and laboratory data of all the patients were evaluated. RESULTS: There were no significant differences between the 12 confirmed COVID-19 (SARS-Cov-2-positive) patients and 16 SARS-CoV-2-negative patients in epidemiology and most of the clinical features or laboratory data. The CT images showed that the incidence of pure/mixed ground-glass opacities (GGOs) was not different between COVID-19 and SARS-CoV-2-negative patients [9/12 (75.0%) vs 10/16 (62.5%), p = 0.687], but pure/mixed GGOs in the peripheral were more common in patients with COVID-19 [11/12 (91.7%) vs 6/16 (37.5%), p = 0.006]. There were no significant differences in the number of lesions, bilateral lung involvement, large irregular/patchy opacities, rounded opacities, linear opacities, crazy-paving patterns, halo signs, interlobular septal thickening or air bronchograms. CONCLUSIONS: Although peripheral pure/mixed GGOs on CT may help distinguish patients with COVID-19 from clinically suspected but negative patients, CT cannot replace RT-PCR testing. ADVANCES IN KNOWLEDGE: Peripheral pure/mixed GGOs on-chest CT findings can be helpful in distinguishing patients with COVID-19 from those with clinically suspected COVID-19 but subsequently found to be COVID-19 negative.


Subject(s)
Coronavirus Infections/diagnostic imaging , Lung/diagnostic imaging , Pneumonia, Viral/diagnostic imaging , Tomography, X-Ray Computed , Adult , Betacoronavirus , COVID-19 , Diagnosis, Differential , Female , Humans , Male , Middle Aged , Pandemics , RNA, Viral/analysis , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction , SARS-CoV-2
7.
Onco Targets Ther ; 12: 8779-8787, 2019.
Article in English | MEDLINE | ID: mdl-31695433

ABSTRACT

PURPOSE: To investigate the predictive capability of clinical parameters for long-term chemotherapy benefits among stage IIIB-IV non-squamous non-small cell lung cancer (NSCLC) patients without sensitive mutations. PATIENTS AND METHODS: We investigated the clinical features of 206 stage IIIB-IV non-squamous NSCLC patients without sensitive mutations and assessed their predictive value for disease control rate (DCR) at 6 and 12 months post-treatment. RESULTS: Seventy-two patients received docetaxel and platinum-based chemotherapy while 134 received pemetrexed and platinum-based chemotherapy. The 6-month and 12-month DCR were 33 (45.8%) and 6 (8.3%) in the docetaxel group and 69 (51.5%) and 19 (14.2%) in the pemetrexed group, respectively. Univariate Cox regression revealed that age, sex, smoking history, adrenal gland metastasis, stage IV disease, neutrophil-to-lymphocyte ratio (NLR), and serum albumin were associated with unfavorable progression-free survival (PFS). Age, stage IV disease, and NLR were identified as independent predictors of PFS using multivariate analysis. NLR was the only parameter that could predict 3-month and 6-month DCRs. NLR and age were able to predict 12-month DCR, with NLR presenting a larger area under the curve. Kaplan-Meier curves demonstrated that patients with NLR > 2.231 displayed significantly reduced long-term disease control. The group with higher NLR had more male patients, lower ALB levels, and serum sodium levels as well as higher platelet counts. CONCLUSION: NLR was an independent predictor of long-term chemotherapy benefits among non-squamous NSCLC patients without sensitive mutations. Patients with lower NLR were optimal candidates for chemotherapy. Patients with high NLR may receive alternative treatments or be included in clinical trials.

8.
World Neurosurg ; 127: e268-e279, 2019 Jul.
Article in English | MEDLINE | ID: mdl-30898742

ABSTRACT

OBJECTIVE: We investigated the use of high-flow superficial temporal artery trunk-to-radial artery-to-middle cerebral artery (STAt-RA-MCA) bypass to prevent ischemic stroke in patients with symptomatic internal carotid artery occlusion (SICAO). METHODS: We retrospectively analyzed the data from patients with SICAO who had undergone high-flow STAt-RA-MCA bypass in our center from October 2014 to November 2017. The incidence of ischemic stroke, changes in cerebral blood flow, characteristics of perioperative complications, and related factors determining the blood flow rate in the graft were analyzed. RESULTS: From October 2014 to November 2017, we treated 21 patients with SICAO using high-flow STAt-RA-MCA bypass. A total of 42 ischemic stroke events had been reported within 6 months before surgery. The ipsilateral/contralateral mean transit time (I/C MTT) ratio before surgery was 1.24 ± 0.10 (range, 1.14-1.51). During a median follow-up period of 692 days (range, 212-1114), 3 transient ischemic attacks occurred in 3 patients; 18 patients (85.7%) did not experience recurrent stroke. The patency rate of the bypass graft was 95.2% (20 of 21). The I/C MTT ratio was 1.06 ± 0.11 on postoperative day 1 in all patients and was significantly different from the preoperative I/C MTT ratio (P < 0.001). The surgical complication rate was 9.5% (2 of 21), and no reoperation was required. CONCLUSION: Our results suggest that high-flow STAt-RA-MCA bypass can effectively reduce the risk of stroke in patients with SICAO. Moreover, the surgical procedure is a highly safe procedure. Further randomized controlled studies are required to draw more precise conclusions.


Subject(s)
Blood Vessel Prosthesis Implantation/methods , Brain Ischemia/prevention & control , Carotid Stenosis/surgery , Cerebral Revascularization/methods , Middle Cerebral Artery/surgery , Radial Artery/transplantation , Temporal Arteries/surgery , Adult , Aged , Angiography, Digital Subtraction , Brain Ischemia/etiology , Carotid Artery, Internal/surgery , Carotid Stenosis/complications , Carotid Stenosis/diagnostic imaging , Cerebral Angiography , Computed Tomography Angiography , Contraindications, Procedure , Female , Humans , Male , Middle Aged , Retrospective Studies
9.
Ther Clin Risk Manag ; 14: 1975-1986, 2018.
Article in English | MEDLINE | ID: mdl-30349276

ABSTRACT

PURPOSE: The effect of glucocorticoid(s) on connective tissue disease (CTD)-related interstitial lung disease (ILD) is controversial. This multicenter study aimed to identify glucocorticoid-sensitive patients using a radiomics approach. METHODS: A total of 416 CTD-ILD patients who began glucocorticoid treatment at the discretion of the attending physician, with or without cyclophosphamide, were included in this study. High doses were defined as pulsed intravenous methylprednisolone, an initial dose of 1 mg/kg/day of prednisolone or 0.8 mg/kg/day of methylprednisolone. Low doses were defined as those less than high doses. Radiomics features were manually extracted from primary lung lesions delineated on computed tomography images, and selected by variance, univariate feature selection, and least absolute shrinkage and selection operator regression model. The prediction models were developed using data from 309 patients from two centers and externally validated in 107 patients from four other hospitals. RESULTS: Treatment response in the training and validation groups was 38.5% and 36.4%, respectively. Eleven radiomics features were selected from 1,029 features with predictive value. Random forest models built for radiomics features to predict treatment response yielded a sensitivity of 0.897. The calibration curve of a nomogram demonstrated good agreement between prediction and observation. Decision curve analysis indicated that glucocorticoid was beneficial if the predicted response rate was 50%-60% for an individual. High doses of glucocorticoids and cyclophosphamide yielded superior efficacy. CONCLUSION: Radiomics-based predictive models reliably identified glucocorticoid-sensitive CTD-ILD patients. Short-term, high-dose glucocorticoid with cyclophosphamide yielded promising results as a potential therapy.

10.
World Neurosurg ; 111: e286-e293, 2018 Mar.
Article in English | MEDLINE | ID: mdl-29269063

ABSTRACT

OBJECTIVE: To investigate the effect of carotid-carotid artery crossover bypass with a synthetic vascular graft for symptomatic type 1A common carotid artery occlusion (CCAO). METHODS: A retrospective analysis was conducted of patients with symptomatic type 1A CCAO who underwent carotid-carotid artery crossover bypass surgery via a retropharyngeal route with a synthetic vascular graft in the Department of Neurosurgery at our hospital. Preoperative demographic data, surgical complications, incidence of stroke during follow-up, and other clinical data were summarized. RESULTS: Between 2011 and 2016, carotid-carotid artery crossover bypass was performed with a synthetic vascular graft in 4 patients with type 1A CCAO. The mean patient age was 63.3 years (range, 49-69 years). Clinical symptoms included dizziness, amaurosis fugax, persistent limb numbness, and transient ischemic attack. In all 4 patients, postoperative computed tomography angiography showed internal carotid artery thickening due to successful bypass, whereas computed tomography perfusion showed improved postoperative cerebral perfusion on the side of the lesion. The sole perioperative complication was a complaint of foreign body sensation on swallowing in 1 patient. The mean duration of follow-up was 40.3 months (range, 14-77 months), during which no newly occurred cerebral ischemia or synthetic vascular graft occlusion was observed. CONCLUSIONS: Carotid-carotid artery crossover bypass with a synthetic vascular graft is a safe and effective therapeutic approach for patients with symptomatic type 1A CCAO. However, studies with larger series are needed to enable more precise conclusions.


Subject(s)
Carotid Stenosis/surgery , Cerebral Revascularization/methods , Vascular Grafting/methods , Aged , Female , Humans , Male , Middle Aged , Retrospective Studies
11.
World J Gastroenterol ; 20(48): 18495-502, 2014 Dec 28.
Article in English | MEDLINE | ID: mdl-25561822

ABSTRACT

Renal aspergillosis (RAsp) is a rare complication in liver transplant (LT) recipients. Here we report RAsp in two LT recipients. In both patients, RAsp occurred more than 90 d after allogenetic orthotropic LT, and all the clinical findings were unspecific. RAsp involved unilateral kidney in Case one and bilateral kidneys in Case two. Both computed tomography (CT) and magnetic resonance imaging (MRI) revealed renal abscesses, with progressively enhanced walls and separations and unenhanced alveolate areas after contrast agent administration. On unenhanced CT images they showed inhomogeneous hypo-attenuation. On fat-suppressed T2-weighted images (T2WIs), the walls and separations of the abscesses showed slightly low signal intensity and the central parts of the lesions showed slightly high signal intensity. Both on CT and MRI, there were some hints of renal infarction or chronic ischemia. Both cases were treated by radical nephrectomy followed by adjuvant antifungal treatment. They all recovered well.


Subject(s)
Abscess/microbiology , Aspergillosis/microbiology , Kidney Diseases/microbiology , Liver Transplantation/adverse effects , Abscess/diagnosis , Abscess/therapy , Antifungal Agents/therapeutic use , Aspergillosis/diagnosis , Aspergillosis/therapy , Biopsy , Humans , Kidney Diseases/diagnosis , Kidney Diseases/therapy , Magnetic Resonance Imaging , Male , Middle Aged , Nephrectomy , Predictive Value of Tests , Reoperation , Tomography, X-Ray Computed , Treatment Outcome
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