This study aimed to investigate the differences in computed tomography findings between mediastinal schwannomas and retroperitoneal schwannomas. Consecutive patients diagnosed with mediastinal or retroperitoneal schwannoma at our hospital between November 2006 and February 2022 were retrospectively recruited. Clinical information and preoperative computed tomography images were collected. Histopathology served as the reference standard for diagnosis. Data collected included sex, symptoms, diameters, morphological characteristics, density, hemorrhage, cystic degeneration, calcification, enhancement, and relationships with adjacent structures. Independent t tests, nonparametric tests, and chi-square tests were used as appropriate. Individual matching was used to control the effect of diameter. Seventy-three participants (34 males and 39 females, mean age: 43 ± 14 years) were finally enrolled. The transverse diameter (P = .012), anteroposterior diameter (P = .042), craniocaudal diameter (P < .001), maximum diameter (P = .012), and average diameter (P = .012) of retroperitoneal schwannomas were significantly higher than those of mediastinal schwannomas, leading to more cystic degeneration and displacement of adjacent structures in retroperitoneal schwannomas. After individual matching, mediastinal schwannomas tended to demonstrate oval (85%) while retroperitoneal schwannomas tended to demonstrate rounded (59%) in shape (P < .001). Calcification (33% vs 0%, P = .002) and heterogeneous density (89% vs 52%, P = .008) were more common in retroperitoneal schwannomas than in mediastinal schwannomas. Cystic degeneration and displacement of adjacent structures were more common in retroperitoneal schwannomas due to larger tumor size. Compared with mediastinal schwannomas, retroperitoneal schwannomas tended to be rounded, calcified, and heterogeneous in density.

To preoperatively predict microvascular invasion (MVI) and relapse-free survival (RFS) in hepatocellular carcinoma (HCC) ≥3 cm by constructing and externally validating a combined radiomics model using preoperative enhanced CT images. This retrospective study recruited adults who underwent surgical resection between September 2016 and August 2020 in our hospital with pathologic confirmation of HCC ≥3 cm and MVI status. For external validation, adults who underwent surgical resection between September 2020 and August 2021 in our hospital were included. Histopathology was the reference standard. The HCC area was segmented on the arterial and portal venous phase CT images to develop a CT radiomics model. A combined model was developed using selected radiomics features, demographic information, laboratory index and radiological features. Analysis of variance and support vector machine were used as features selector and classifier. Receiver operating characteristic (ROC) curves, calibration curves and decision curve analysis (DCA) were used to evaluate models’ performance. The Kaplan-Meier method and log-rank test were used to evaluate the predictive value for RFS. A total of 202 patients were finally enrolled (median age, 59 years, 173 male). Thirteen and 24 features were selected for the CT radiomics model and the combined model, and the area under the ROC curves (AUC) were 0.752 (95

Background and objective:The color-coded multiphase computed tomography angiography (cmCTA) is an accredited technique that employs color-coding to visually depict the temporal dynamics of collateral blood flow in patients with acute ischemic stroke (AIS). This research aimed to assess the quantification of cmCTA in AIS patients for characterizing arterial and venous collateral flow, and predicting functional outcomes. Methods:A retrospective study was performed on a consecutive cohort of AIS patients with large vessel occlusion who underwent cmCTA scan and reconstruction. Collateral ratio and delayed vessel ratio (DVR) were determined through semi-automatic delineation and calculation on the anterior cerebral artery regions and Alberta Stroke Program Early CT (ASPECT) Score regions of cmCTA maps. Deep venous outflow (DVO) and superficial venous outflow (SVO) scores were assessed using a 6-point scale. Logistic regression and propensity score were applied to confounding factors adjustment and model construction. Receiver operating characteristic curve, calibration curve, and decision curve analysis were utilized to evaluate the prediction model of functional independence and excellent recovery. Results:Well-developed arterial collaterals as depicted by low DVR and adequate venous collaterals as indicated by high DVO or SVO were correlated with better outcomes (All p < 0.001). Adjusted DVR showed areas under the curve of 0.81-0.90 for predicting functional independence and excellent recovery. Adjusted DVO showed areas under the curve of 0.88 for predicting functional independence and excellent recovery. Each prediction model demonstrated good precision and net benefit. Conclusion:The application of DVR and other parameters in cmCTA offers a quantitative perspective on the conventional ASPECT scoring scheme utilizing grayscale CT images. DVR from cmCTA may enhance pre-treatment collateral assessment and post-treatment outcome prediction in AIS, facilitating informed treatment decisions.

BACKGROUND:Mechanical thrombectomy (MT) has been recognized as a groundbreaking intervention for acute ischemic stroke (AIS) resulting from large vessel occlusion (LVO). Traditional imaging parameters frequently fall short in synthetically encapsulating the heterogeneity of thrombi and the dynamics of collateral circulation. AIM:This study seeks to investigate the integration of venous-phase clot radiomics features with arterial-level collateral scores obtained from color-coded multi-phase CT angiography (mCTA) to predict neurological improvement (NI) following MT in LVO-AIS patients. METHODS:A retrospective analysis was conducted on a series of adult patients with LVO-AIS who underwent mCTA followed by MT. Radiomic features were extracted from the peak-venous and late-venous phases of the mCTA. Subsequently, a machine learning algorithm was employed to develop radiomic models. The regional leptomeningeal collateral (rLMC) score, derived from color-coded mCTA maps, was documented to assess arterial-level collateral status. Another fusion model integrating clinical, collateral, and radiomics data was constructed using logistic regression to predict NI status. RESULTS:The study included 110 AIS patients in which the rLMC score was significantly higher in the NI group compared to the non-NI group (P<0.001). The clot-based radiomics model exhibited good predictive performance, with AUC values of 0.986 (training set) and 0.831 (test set) for the peak-venous phase. The fusion model based on peak venous phase data, incorporating clinical parameters, rLMC score, and radiomics features, showed superior predictive accuracy (AUC: 0.992 in training set, 0.889 in test set). Corresponding DCA indicate that the combined model demonstrates the optimal potential clinical benefits. CONCLUSION:The integration of venous-phase clot radiomics features with arterial-level collateral scores and clinical parameters effectively predicts NI after MT in AIS patients.

Non-ketotic hyperglycaemia (NKH)-induced hemichorea-hemiballismus (HC-HB) is an infrequent reversible condition observed in individuals with poorly controlled diabetes. In this report, we present a case of NKH-induced HC-HB exhibiting distinctive morphological and functional alterations on conventional magnetic resonance imaging (MRI), diffusion-weighted imaging (DWI), and 1H magnetic resonance spectroscopy (MRS), followed by subsequent monitoring. A 70-year-old male with a 20-year history of diabetes presented with severe unilateral involuntary movement. Computer tomography revealed heightened attenuation in the left putamen and caudate nucleus. The conventional MRI revealed the presence of focal T2-hyperintensity, noticeable mass effect, and ring-like enhancement, which are indicative of glioma. Additionally, the DWI showed unrestricted diffusion of water molecules within the lesion. MRS analysis further demonstrated significantly elevated lactate (Lac) and lipids (Lip), minimal increased choline (Cho), basically stable creatine (Cr), and modest decreased N-acetylaspartate (NAA) levels (which remained larger than both Cho and Cr peaks), leading to a diagnosis of NKH-induced HC-HB. This report emphasizes the significance of acknowledging that NKH-induced HC-HB can manifest with imaging features that bear resemblance to those of glioma. The presence of a slightly elevated Cho/NAA ratio alongside a notable increase in Lac/Lip peak on MRS may aid in ruling out neoplastic conditions.

Background Abdominal CT scans are vital for diagnosing abdominal diseases but have limitations in tissue analysis and soft tissue detection. Dual-energy CT (DECT) can improve these issues by offering low keV virtual monoenergetic images (VMI), enhancing lesion detection and tissue characterization. However, its cost limits widespread use. Purpose To develop a model that converts conventional images (CI) into generative virtual monoenergetic images at 40 keV (Gen-VMI40keV) of the upper abdomen CT scan. Methods Totally 444 patients who underwent upper abdominal spectral contrast-enhanced CT were enrolled and assigned to the training and validation datasets (7:3). Then, 40-keV portal-vein virtual monoenergetic (VMI40keV) and CI, generated from spectral CT scans, served as target and source images. These images were employed to build and train a CI-VMI40keV model. Indexes such as Mean Absolute Error (MAE), Peak Signal-to-Noise Ratio (PSNR), and Structural Similarity (SSIM) were utilized to determine the best generator mode. An additional 198 cases were divided into three test groups, including Group 1 (58 cases with visible abnormalities), Group 2 (40 cases with hepatocellular carcinoma [HCC]) and Group 3 (100 cases from a publicly available HCC dataset). Both subjective and objective evaluations were performed. Comparisons, correlation analyses and Bland-Altman plot analyses were performed. Results The 192nd iteration produced the best generator mode (lower MAE and highest PSNR and SSIM). In the Test groups (1 and 2), both VMI40keV and Gen-VMI40keV significantly improved CT values, as well as SNR and CNR, for all organs compared to CI. Significant positive correlations for objective indexes were found between Gen-VMI40keV and VMI40keV in various organs and lesions. Bland-Altman analysis showed that the differences between both imaging types mostly fell within the 95% confidence interval. Pearson's and Spearman's correlation coefficients for objective scores between Gen-VMI40keV and VMI40keV in Groups 1 and 2 ranged from 0.645 to 0.980. In Group 3, Gen-VMI40keV yielded significantly higher CT values for HCC (220.5HU vs. 109.1HU) and liver (220.0HU vs. 112.8HU) compared to CI (p < 0.01). The CNR for HCC/liver was also significantly higher in Gen-VMI40keV (2.0 vs. 1.2) than in CI (p < 0.01). Additionally, Gen-VMI40keV was subjectively evaluated to have a higher image quality compared to CI. Conclusion CI-VMI40keV model can generate Gen-VMI40keV from conventional CT scan, closely resembling VMI40keV.

Objectives To investigate whether cerebral collateral and venous outflow (VO) patterns on colour-coded multi-phase computed tomography angiography (mCTA) can estimate ischaemic core growth rate (IGR) and predict 90-day functional independence for patients with late-presenting acute ischaemic stroke (AIS).Methods The retrospective analysis included 127 AIS patients with a late time window. All patients underwent baseline mCTA with colour-coded reconstruction and computed tomography perfusion. Both collateral score and VO score on colour-coded mCTA maps were analysed and recorded. The IGR was calculated as ischaemic core volume divided by the time from onset to imaging. A 90-day modified Rankin Scale score of 0-2 was defined as functional independence. Kendall's Tau-b analysis was used for nonparametric correlation analysis. Propensity scores, logistic regressions, and receiver operator characteristic (ROC) curves were applied to construct the prediction model.Results Moderate correlations were found between collateral delay and IGR (Tau-b = -0.554) and between VO and IGR (Tau-b = -0.501). High collateral score (odds ratio = 3.01) and adequate VO (odds ratio = 4.89) remained independent predictors for 90-day functional independence after adjustment. The joint predictive model, which integrated the VO score and clinical features, demonstrated an area under the ROC curve (AUC) of 0.878. The AUCs of collateral score and VO score were 0.836 and 0.883 for outcome prediction after adjustment.Conclusions Cerebral collateral and VO patterns based on colour-coded mCTA can effectively predict infarct progression and 90-day clinical outcomes, even for AIS patients beyond the routine time window.Advances in knowledge Colour-coded mCTA is a readily understandable post-processing technique for the rapid assessment of collateral circulation and VO status in stroke imaging. A moderate correlation was observed between the characteristics of collateral delay/VO on colour-coded mCTA and IGR in patients with AIS. Both high-quality collateral circulation and "red superficial middle cerebral vein sign" can predict 90-day functional independence even for patients beyond the routine time window.

The purpose of this study is to evaluate the performance of radiomic models in acute thoracolumbar vertebral compression fractures (VCFs) and their impact on radiologists. In this monocentre retrospective study, eligible for inclusion were adults who underwent emergent thoracic/lumbar CT between May 2022 and November 2023 in our hospital diagnosed with thoracolumbar VCFs. The lesions were randomly divided at a ratio of 7:3 into a training set and test set. For external validation, consecutive patients who underwent emergent thoracic/lumbar CT between January 2022 and April 2022 were included. MRI and previous imaging were used as reference standard. The vertebral body area was manually segmented. Logistic regression was used to construct a CT radiomic model and a combined model, including Relief-selected radiomic features and clinical information. The radiologists’ diagnosis with and without the models was recorded. The performance was assessed using receiver operating characteristic curves (ROC), calibration curves (CC) and decision curve analysis (DCA). Of 235 VCFs in 147 patients (median age, 73 years, 66 male) included, the diagnosis of acute VCFs was confirmed in 126. The area under the ROC of the CT radiomics model and the combined model in the external validation set were 0.883 (95

This study aims to explore the utility of ColorViz mapping from dual data sources for assessing arterial collateral circulation and predicting cerebral tissue-level collateral (TLC) in patients with acute ischemic cerebrovascular diseases. A retrospective study was conducted at a single center on a cohort of 79 patients diagnosed with acute ischemic cerebrovascular diseases between November 2021 and April 2022, who had undergone both multi-phase CT angiography (mCTA) and computed tomography perfusion (CTP). The quality of images and arterial collateral status depicted on ColorViz maps from dual data-sets (mCTA and CTP) were assessed using a “5-point scale” and a “10-point scale,” respectively. The status of TLC was evaluated by analyzing multilevel hypoperfusion volume and the hypoperfusion intensity ratio (HIR). The Spearman correlation coefficient was employed to examine the association between arterial collateral status derived from dual data sources and TLC. Receiver operating characteristic curve analysis was used to determine the diagnostic efficacy in detecting large vessel occlusive acute ischemic stroke (LVO-AIS). The ColorViz maps derived from dual data sources facilitated comparable image quality, with over 95% of cases meeting diagnostic criteria, for the evaluation of arterial level collateral circulation. Patients with robust arterial collateral circulation, as determined by dual data sources, were more likely to exhibit favorable TLC status, as evidenced by reductions in hypoperfusion volume (Tmax > 4 seconds, Tmax > 6 seconds, Tmax > 8 seconds, and Tmax > 10 seconds, P < .05) and HIR (Tmax > 6 seconds/4 seconds, Tmax > 8 seconds/4 seconds, Tmax > 10 seconds/4 seconds, and Tmax > 8 seconds/6 seconds, P < .05). The sensitivity and specificity in detecting LVO-AIS was 60.00% and 97.73% for mCTA source maps, while 74.29% and 72.73% for CTP source maps (P > .05 based on De-Long test). In conclusion, this study indicates that ColorViz maps derived from both data sources are equally important in evaluating arterial collateral circulation and enhancing diagnostic efficiency in patients with LVO-AIS, as well as offering insights into the TLC status based on hypoperfusion volume and HIR.

Background Color-coded multiphase computed tomography angiography (mCTA) can provide time-variant blood flow information of collateral circulation for acute ischemic stroke (AIS). Purpose To compare the predictive values of color-coded mCTA, conventional mCTA, and CT perfusion (CTP) for the clinical outcomes of patients with AIS. Material and Methods Consecutive patients with anterior circulation AIS were retrospectively reviewed at our center. Baseline collateral scores of color-coded mCTA and conventional mCTA were assessed by a 6-point scale. The reliabilities between junior and senior observers were assessed by weighted Kappa coefficients. Receiver operating characteristic (ROC) curves and multivariate logistic regression model were applied to evaluate the predictive capabilities of color-coded mCTA and conventional mCTA scores, and CTP parameters (hypoperfusion and infarct core volume) for a favorable outcome of AIS. Results A total of 138 patients (including 70 cases of good outcomes) were included in our study. Patients with favorable prognoses were correlated with better collateral circulations on both color-coded and conventional mCTA, and smaller hypoperfusion and infarct core volume (all P < 0.05) on CTP. ROC curves revealed no significant difference between the predictive capability of color-coded and conventional mCTA (P = 0.427). The predictive value of CTP parameters tended to be inferior to that of color-coded mCTA score (all P < 0.001). Both junior and senior observers had consistently excellent performances (kappa = 0.89) when analyzing color-coded mCTA maps. Conclusion Color-coded mCTA provides prognostic information of patients with AIS equivalent to or better than that of conventional mCTA and CTP. Junior radiologists can reach high diagnostic accuracy when interpreting color-coded mCTA images.

目的 探讨双源CT冠状动脉钙化积分(CaCS)和腹主动脉钙化评分(AACS)与Ⅲ～Ⅴ期慢性肾功能不全(CKD)的相关性.方法 回顾性分析63例Ⅲ～Ⅴ期CKD患者.所有患者均行双源CT及腹部侧位X平片检查.测量冠状动脉各分支的CaCS值、总CaCS值及AACS值.采用Kruskal-Wallis检验、χ2检验或Fisher精确检验评价各指标差异.采用Spearman相关性分析评价不同期CKD与CaCS的相关性.结果 随着CKD的进展,总CaCS也随之显著增加(P<0.05).不同期CKD与冠状动脉钙化的发生率(r=0.53,P=0.000)、多支冠状动脉血管钙化的发生率(r=0.32,P=0.01)均呈正相关;不同期CKD的冠状动脉钙化更好发于LAD、LCX及RCA,其钙化的发生率与CKD分期呈正相关(P<0.05).结论 Ⅲ-～Ⅴ期CKD与CaCS的密切相关.随着CKD的进展,冠状动脉钙化发生率越高,累及的范围更广.

Abstract Background and Objectives The Alberta Stroke Program CT Score (ASPECTS) is a widely used rating system for assessing infarct extent and location. We aimed to investigate the prognostic value of ASPECTS subregions’ involvement in the long-term functional outcomes of acute ischemic stroke (AIS). Materials and Methods Consecutive patients with AIS and anterior circulation large-vessel stenosis and occlusion between January 2019 and December 2020 were included. The ASPECTS score and subregion involvement for each patient was assessed using posttreatment magnetic resonance diffusion-weighted imaging. Univariate and multivariable regression analyses were conducted to identify subregions related to 3-month poor functional outcome (modified Rankin Scale scores, 3–6) in the reperfusion and medical therapy cohorts, respectively. In addition, prognostic efficiency between the region-based ASPECTS and ASPECTS score methods were compared using receiver operating characteristic curves and DeLong’s test. Results A total of 365 patients (median age, 64 years; 70% men) were included, of whom 169 had poor outcomes. In the reperfusion therapy cohort, multivariable regression analyses revealed that the involvement of the left M4 cortical region in left-hemisphere stroke (adjusted odds ratio [aOR] 5.39, 95% confidence interval [CI] 1.53–19.02) and the involvement of the right M3 cortical region in right-hemisphere stroke (aOR 4.21, 95% CI 1.05–16.78) were independently associated with poor functional outcomes. In the medical therapy cohort, left-hemisphere stroke with left M5 cortical region (aOR 2.87, 95% CI 1.08–7.59) and caudate nucleus (aOR 3.14, 95% CI 1.00–9.85) involved and right-hemisphere stroke with right M3 cortical region (aOR 4.15, 95% CI 1.29–8.18) and internal capsule (aOR 3.94, 95% CI 1.22–12.78) affected were related to the increased risks of poststroke disability. In addition, region-based ASPECTS significantly improved the prognostic efficiency compared with the conventional ASPECTS score method. Conclusion The involvement of specific ASPECTS subregions depending on the affected hemisphere was associated with worse functional outcomes 3 months after stroke, and the critical subregion distribution varied by clinical management. Therefore, region-based ASPECTS could provide additional value in guiding individual decision making and neurological recovery in patients with AIS.

目的 探讨超高分辨CT(U-HRCT)靶重建在新型冠状病毒肺炎(COVID-19)精准诊断中的价值.方法 回顾性分析13例COVID-19,44例其他肺炎,6例磨玻璃结节患者的CT图像,分为A组(C-HRCT)及B组(U-HRCT),分别采取iDose4-3、iDose4-5进行回顾性靶重建,评估不同重建图像在同一层面肺窗的CT值、噪声(SD)、信噪比(SNR);2名影像学医师以5分制对图像质量及显示病灶结构进行主观评分.结果 同一选代等级,U-HRCT图像的SNR低于C-HRCT图像,SD高于C-HRCT图像,差异有统计学意义(P＜0.05).二元logistic回归分析显示磨玻璃病灶内血管增粗、病灶胸膜下分布、小叶间隔显示和铺路石征象是判断COVID-19的独立预测因子.U-HRCT对磨玻璃病灶内血管增粗、支气管管壁及小叶间隔显示上优于C-HRCT,差异有统计学意义(P＜0.05).结论 U-HRCT在诊断COVID-19较C-HRCT有优势,特别是在显示病灶关键细节方面.

目的:探讨新型冠状病毒肺炎早期超高分辨率CT影像及随访的影像变化.方法:回顾性分析我院自2020年1月24日至2月6日确诊的11例新型冠状病毒肺炎患者的171个病灶,分析病灶的分布、形态、密度、内部及周边特征等影像学表现,并采用人工智能方法对11例患者早期CT随访的磨玻璃影及实变影标准化体积进行定量分析和比较.结果:114(67％)个病灶位于胸膜下区及肺外带区,35(20％)个沿支气管血管分布,22(13％)个病灶位于肺中内带.159(93％)个病灶为小叶/小斑片影.138(81％)个病灶表现为纯磨玻璃影,27(16％)个为混合磨玻璃影,6(4％)个为实变影.64(37％)个病灶内血管增粗,57(33％)个小叶间隔增厚,69(40％)个小叶内间隔增厚,33(19％)个可见含气支气管影,25(15％)个胸膜增厚和粘连,22(13％)个胸膜下病灶可见透亮区影.早期CT随访显示磨玻璃影(p=0.003)和实变影标准化体积(p=0.003)显著增加.结论:新型冠状病毒肺炎早期超高分辨率CT表现为沿胸膜下/外周分布的多发小叶性/小斑片状纯磨玻璃斑片影,常伴病灶内血管增粗和小叶内/小叶间隔增厚等表现;早期复查磨玻璃影及实变影病灶明显增多、增大、融合.具有一定的特征性影像表现,结合流行病学及临床表现,有助于疑似病例的早期诊断.

目的 评价CT肺动脉造影(CTPA)在血液恶性肿瘤患者肺部侵袭性霉菌感染(IMD)诊断中的应用价值.方法 依据《侵袭性肺部真菌感染的诊断标准与治疗原则》,于2018年3月至2019年4月共纳入40例厦门大学附属中山医院血液科的血液系统恶性肿瘤患者,并进一步将其分为确诊、临床诊断和拟诊.对所有患者行CTPA检查,观察影像与临床/微生物之间的关系以及能否利用CTPA协助发现拟诊分类中的IMD患者.结果 所有确诊的6例患者均出现肺血管栓塞改变的阳性结果;9例临床诊断患者中,8例CTPA阳性,1例CTPA阴性;25例拟诊患者中,12例CTPA阳性,13例CTPA阴性.结论 CTPA可直接发现可疑肺IMD患者肺血管闭塞,其在血液恶性肿瘤患者肺IMD的早期诊断价值值得进一步探讨.

目的 探讨双能CT的单能量图像和融合图像在下肢动脉的应用价值.方法 对行下肢动脉双能量成像的患者所采集图像数据进行回顾性重组得到权重配比为0.7的线性融合图像、最佳非线性融合图像(OCM),根据对比噪声比(CNR)能谱曲线优选的最佳单能量图像(Mono-E),比较三组图像下肢各段动脉(腹主动脉分叉、髂总动脉分叉、股动脉中段、腘动脉近端)的CT值、噪声(SD)、CNR、信噪比(SNR)及进行主观图像质量评分.结果 线性融合图像、OCM图像及Mono-E图像的下肢各段动脉平均CT值分别为(456.80±154.56)HU、(559.35±187.88)HU、(505.03±170.97) HU,三者间差异有统计学意义(P＜0.05);SD分别为(14.56±5.28) HU、(12.50±4.78)HU、(15.33±6.44) HU,三者间差异有统计学意义(P＜0.05);CNR分别为30.47±15.60、46.76±25.89、34.20±20.88,三者间差异有统计学意义(P＜0.05);SNR分别为34.86±16.85、50.67±26.45、38.67±22.55,三者间差异有统计学意义(P＜0.05).OCM图像的CT值、CNR、SNR均高于线性融合图像及Mono-E图像,差异具有统计学意义(P＜0.05).下肢动脉腘动脉段最佳CNR单能量水平在61 ～ 66 keY,平均(63.03±1.29) keV.图像质量主观评分方面,OCM与Mono-E图像评分高于线性融合图像,差异具有统计学意义(P＜0.05);在主髂动脉部分,三组图像评分差异无统计学意义(P＞ 0.05);在膝下动脉部分,Mono-E图像评分高于OCM图像,差异具有统计学意义(P＜0.05).结论 下肢动脉双能CT成像中OCM图像质量最好.最佳单能量(63 keY)图像成像质量有所提高,在膝下动脉分支显示上有优势,可以在临床血管成像方面广泛应用.

Objective:To establish and verify the prediction model of benign or malignant of solitary pulmonary nodules (SPNs≤20 mm) based on artificial intelligence.Methods:Totally 338 SPNs (≤20 mm) from 279 patients, confirmed by operation and pathology, were selected in Zhongshan Hospital Xiamen University from November 2018 to May 2020. Clinical data (age, gender, smoking history, individual and family history of malignancy), image features (maximum diameter, minimum diameter, solid proportion, volume, lobulation sign, burr sign, vacuole sign, cavity sign, pleural indentation sign, and radiomic features (maximum CT value, minimum CT value, average CT value, median CT value, CT value standard deviation, skewness, peak, energy, entropy) were analyzed retrospectively. All the data of patients were randomly divided into training set (271 SPNs) and test set (67 SPNs). In the training set, the clinical, image features and radiomic features were first selected by the least absolute shrinkage and selection operator (LASSO) regression, then the independent risk factors of SPN (≤20 mm) were screened out by multi-variate logistic regression analysis, and the nomogram prediction models were constructed. Finally, the data of test set were used to verify the prediction model by the ROC curve and calibration curve (CC).Results:In the training set of 271 SPNs, 81 SPNs were benign and 190 malignant. After analysis of LASSO regression and multi-factor logistics regression, the independent predictors of benign or malignant SPN were age, gender, largest diameter, vacuole sign and solid proportion. The prediction model was P=e x/(1+e x), x=-2.583+0.027×age+1.519×gender+0.127×maximum diameter-2.132×solid proportion+1.720×vacuole sign. The results of the model showed that the area under curve (AUC) of ROC was 0.850, and the sensitivity was 73.7%, specificity was 82.7% and accuracy was 82.3%. In the test set of 67 SPNs, 22 SPNs were benign and 45 malignant. The results showed that the AUC of ROC was 0.882, and the sensitivity was 82.2%, specificity was 81.8% and accuracy was 85.1%. The calibration nomogram of prediction model showed that CC from training set or test set well coincided with its individual ideal curve ( Ptraining=0.688, Ptest=0.618). Conclusion:Prediction model of benign or malignant SPN ≤20 mm is established based on AI; it can obtain the prediction probability and has good diagnostic efficiency.

目的 评价超高分辨CT(UHRCT)结合iDose4迭代算法的图像质量,探讨其在新型冠状病毒肺炎(COVID-19)诊断中的应用价值.方法 对行Philips Ingenuity CT扫描的25例疑似COVID-19患者原始CT图像,分512矩阵组及1024矩阵组,采取传统滤过反投影法(FBP)及iDose4-1、iDose4-3、iDose4-5、iDose4-7进行回顾性重建,测量不同重建图像肺窗同一层面的CT值、噪声(SD)、信噪比(SNR);由3名影像学高级职称医师以5分制对图像质量及显示肺小叶结构进行主观评分.所有数值进行SPSS统计学分析.结果 iDose4-1、iDose4-3、iDose4-5、iDose4-7的SNR均高于FBP,噪声低于FBP,差异有统计学意义(P<0.05),各组图像的CT值差异无统计学意义(P>0.05).随着iDose4级别的增高,SD值下降,SNR值升高.同一迭代等级,1024矩阵组SD值高于512矩阵组,SNR值低于512矩阵组,差异具有统计学意义(P<0.05).两两比较显示,1024矩阵组iDose4-5、iDose4-7与512矩阵组iDose4-3的SD、CNR差异无统计学意义(P>0.05).FBP、不同级别迭代重建图像主观评分差异有统计学意义(P<0.05).各组间两两比较,同一矩阵条件下iDose4-3、iDose4-5的主观评分值差异无统计学意义(P>0.05),且1024矩阵iDose4-5主观评分优于其它组,差异有统计学意义(P<0.05).结论 1024矩阵超高分辨CT结合iDose4-5重建可以更清楚显示肺小叶结构、磨玻璃病灶及细或末梢支气管扩张,有利于精准评估COVID-19病变的累及范围及程度.

目的 探讨新型冠状病毒肺炎早期薄层CT影像表现.方法 回顾性分析我院自2020年1月24日至3月29日确诊的14例新型冠状病毒肺炎患者的207个病灶,分析病灶的分布、形态、密度、内部及周边特征等影像学表现.结果 143个(69.1％)病灶位于胸膜下区及肺外带区,39个(18.8％)沿支气管血管分布,25个(12.1％)病灶位于肺中内带.187个(90.3％)病灶为小叶状/小斑片影.158个(76.3％)病灶表现为纯磨玻璃影,42个(20.3％)为混合磨玻璃影,7个(3.4％)为实变影.77个(37.2％)病灶内血管增粗,67个(32.4％)小叶间隔增厚,43个(20.8％)小叶内间隔增厚,46个(22.2％)可见含气支气管影,34个(16.4％)胸膜增厚和粘连,23个(11.1％)胸膜下病灶可见透亮区影.结论 新型冠状病毒肺炎早期薄层CT表现为沿胸膜下/外周分布的多发小叶状/小斑片状纯磨玻璃斑片影,常伴病灶内血管增粗和小叶内/小叶间隔增厚等表现.具有一定的特征性影像表现,结合流行病学及临床表现,有助于疑似病例的早期诊断.

目的 基于CTA扫描数据探讨椎基底动脉(VBA)影像解剖特征,为椎基底动脉延长症(VBD)诊断提供量化评估指标.方法 回顾性分析符合纳入标准的行头颈CTA检查者302例,根据VBA形态特点分为均衡型和非均衡型两组,非均衡组分为L型和S型,测量各组椎动脉(VA)颅内段和基底动脉(BA)的直径、长度及BA分叉高度.结合容积再现图像,计算VA及BA的迂曲度(TI).在寰枕关节水平层面、颈静脉孔水平、内听道水平、鞍背层面分别测量及计算VA、BA偏移正中矢状面的距离.血管的径线、长度及迂曲度均计算其95％可信区间(CI).结果 不同类型VBA年龄、性别构成上差异具有统计学意义(P＜0.05).左右VA直径、长度、迂曲度的95％CI分别为3.08～3.27 mm、2.68～2.87 mm,40.38～41.97 mm、39.89～41.75 mm、0.219～0.257 mm、0.140～0.203 mm.BA 直径、长度、高度及迂曲度95％CI 分别为3.14～3.29、28.13～29.16 mm、3.82～4.72 mm、0.091～0.119 mm.左右VA直径、迂曲度差异均具有统计学意义(P＜0.05).各类型VBA直径、长度、迂曲度差异具有统计学意义(P＜0.05).在颈静脉孔水平、内听道水平,各型VA、BA到正中矢状面的最大偏移距离差异具有统计学意义(P＜0.05).结论 CTA定量数据能直观反映VBA形态学特点,为VBD的诊断提供定量影像学依据.