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Objective:To investigate the stability and feasibility of improved silent MRA technique based on hybrid-arterial spin labeling(ASL) for imaging intracranial arterial stenosis.Methods:From September 2019 to May 2020, totally 35 patients with suspected intracranial vascular stenosis in Department of Neurology of Northern Jiangsu People′s Hospital were enrolled in this study. Silent MRA and improved silent MRA based on hybrid-ASL technique were performed respectively. The acquisition noise (noise measurement and subjective score) of two kinds of MRA examination were evaluated respectively. Two neuroradiologists performed image quality scoring and signal-to-noise ratio (SNR) measurement of intracranial arteries (including internal carotid artery, vertebrobasilar artery, anterior cerebral artery, middle cerebral artery, and posterior cerebral artery) in the two kinds of MRA images using a double-blind, completely randomized method. Independent sample t-test was used to compare the image quality and SNR of two kinds of MRA images in each segment. Two experts assessed the degree of stenosis at the site of confirmed intracranial artery stenosis. Kappa test was used to assess interobserver and intermodel agreement. Results:There was no significant difference in acquisition noise between improved silent MRA and silent MRA ( P>0.05). In all five segments measured, the image quality scores of internal carotid artery [(4.40±0.49)scores], anterior cerebral artery[(4.30±0.33)scores] and middle cerebral artery [(4.46±0.34)scores] in improved silent MRA were higher than those in silent MRA images [(4.02±0.43)scores, (4.02±0.31)scores, (4.02±0.31)scores; t=2.825, 2.877, 1.683, all P<0.05)]. The SNR of internal carotid artery (9.11±1.23) and middle cerebral artery (8.77±1.87) in improved silent MRA images was higher than that in silent MRA images (7.83±1.33, 8.06±2.67, respectively; t=11.154, 3.268, both P<0.05). A total of 24 patients (38 lesions) with intracranial vascular stenosis were diagnosed by CTA. Improved silent MRA (Kappa=0.89, 95%CI 0.82-0.95) and silent MRA (Kappa=0.85, 95%CI 0.77-0.92) were highly consistent among observers in evaluating the degree of cerebrovascular stenosis.The results of improved silent MRA were highly consistent with those of CTA (Kappa=0.92, 95%CI 0.87-0.98), and those of silent MRA were highly consistent with those of CTA (Kappa=0.85, 95%CI 0.77-0.92). Conclusions:The improved silent MRA is feasible to improve the imaging quality and signal uniformity through efficient marking based on keeping the low noise features. In the diagnosis of intracranial stenosis and occlusive disease, the stability of improved silent MRA imaging improves the diagnostic efficiency of stenosis to a certain extent.
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Objective:To evaluate image quality and diagnostic performance of silent MR angiography (MRA) and discuss the feasibility of silent MRA in diagnosing intracranial aneurysms.Methods:Twenty seven patients suspected with cerebrovascular disorders and 30 intracranial aneurysms in Northern Jiangsu People's Hospital, were enrolled prospectively in this study from December 2015 to December 2018. Silent and time of flight (TOF) MRA were performed on the same day prior to CTA examination. The corresponding MRA images were independently and blindly evaluated by two experienced neuroradiologists in the aspects of signal homogeneity, lesion conspicuity, venous signal/artifact and diagnostic confidence (4-point scale). The aneurysms were divided into tiny (≤ 3 mm) and non-tinyaneurysm groups(> 3 mm) according to the measured diameters of aneurysms. The differences in image quality ratings between silent MRA and TOF MRA were analyzed using Wilcoxon signed rank tests. Intra-class correlation coefficients (ICC) were used to test the consistency of measurements between MRAs (silent MRA, TOF MRA) and CTA.Results:CTA revealed 32 intracranial aneurysms. For silent MRA and TOF MRA, the scores of signal homogeneity were 3.38±0.49 and 3.00±0.62, andthe scores of venous signal/artifact were 3.77±0.42 and 2.65±0.48.Significant differences were found between the two MRAs in these aspects ( Z=-2.21, P=0.02; Z=-5.69, P=0.01). The scores of lesion conspicuity were 3.19±0.56 and 3.15±0.46, and the scores of diagnostic confidence were 3.27±0.44 and 3.12±0.51.There were no significant differences found in these aspects ( P>0.05).The ICC coefficient was excellentfor silent MRA (0.94, 95%CI 0.82- 0.98)and was good for TOF MRA (0.72, 95%CI 0.30-0.91) in tiny aneurysm group. The ICC coefficient was excellent (silent MRA, 0.98, 95%CI 0.95-0.99; TOF MRA, 0.95, 95%CI 0.87-0.98) for both MRA in non-tiny aneurysm group. Conclusions:Compared with TOF MRA, silent MRA could achieve higher image quality and higher diagnostic confidence, and higher consistency with CTA. Silent MRA can be a promising non-contrast-enhanced alternative MRA technique in clinical setting.
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Objective@#To investigate alterations of blood perfusion in subcortical regions in patients with Parkinson′s disease (PD) by three dimentional arterial spin labeling (ASL) magnetic resonance imaging (MRI).@*Methods@#Thirty patients with PD and 40 control subjects were recruited from the inpatient and outpatient of the Department of Neurology of Northern Jiangsu People′s Hospital during October 2014 to October 2016, and routine brain MRI and 3D pseudo-continuous pulse ASL were performed on all the subjects. The cerebral blood flow (CBF) maps derived from 3D ASL were coregistered to the Montreal Neurological Institute brain space. The stereo-templates of bilateral caudate nucleus, putamen nucleus, globus pallidum and thalamus from Anatomical Automatic Labeling were used as region of interest (ROI) to exstract absolute CBF values in these subcortical regions, respectively. The CBF ratio (rCBF) values represented by individual whole brain CBF divided by each of the regional CBF were also calculated in consideration of the difference between individual whole brain CBF. The CBF and rCBF values were compared respectively between groups by one-way analysis of variance.@*Results@#The subcortical CBF values (ml·100 g-1·min-1) for each ROI in PD (caudate nucleus (left: 35.32±6.47, right: 36.17±7.07), globus pallidum (left: 40.42±5.83, right: 40.18±5.70), putamen nucleus (left: 41.97±6.12, right: 42.91±6.43) and thalamus (left: 46.58±7.71, right: 49.11±7.10)) were significantly lower than that in the control group (caudate nucleus (left: 41.38±7.05, right: 41.63±6.85), globus pallidum (left: 45.65±8.35, right: 45.53±8.94), putamen nucleus (left: 48.49±8.78, right: 48.99±8.88) and thalamus (left: 54.32±11.94, right: 56.21±11.98), F=13.58, 10.56, 12.11, 10.06, 8.59, 8.23, 9.57, 8.30, P=0.000, 0.002, 0.005, 0.005, 0.001, 0.002, 0.003, 0.005, respectively). The whole brain mean CBF values of each subject were also extracted and compared bewteen groups, and mean CBF values (ml·100 g-1·min-1) in PD patients (42.14±9.61) decreased significantly than those in the control group (51.59±9.67, F=16.42, P<0.01), and there was a 18.31% decrement in whole brain mean CBF in the patient group. However, rCBF values for almost all subcortical ROIs of the patients significantly increased when compared with the control group.@*Conclusions@#The decreased absolute cerebral blood perfusion involved not only subcortical regions, but also the whole brain level in the course of PD. The CBF metabolism in patients with PD may have been redistributed, with relative hyperperfusion in the subcortical brain regions contrast to the whole brain perfusion level of patients themselves.
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Objective To investigate the feasibility of histogram analysis in differentiating brain high-grade glioblastomas,primary lymphoma from metastatic tumor.Methods 26 cases of brain high-grade glioblastomas,22 cases of primary lymphoma and 18 cases of metastatic tumor confirmed by postoperative pathological were analyzed retrospectively.Delineation of ROI and extraction of texture parameters were performing by using Mazda software.The histogram parameters,including Mean,Variance,Skewness,Kurtosis,Perc0.1%,Perc10%,Perc50%, Perc90% and Perc99% were analyzed statistically,and the ROC was then established.Results Mean,Perc0.1%,Perc10%and Perc50% exhibited statistically significant differences (P＜0.05).The best diagnostic parameters for differentiation between brain high-grade glioblastomas and primary lymphoma,primary lymphoma and metastatic tumor,and brain high-grade glioblastomas and metastatic tumor were Perc0.1%,Perc0.1%and Kurtosis.The AUC for these preferred diagnostic parameters were 0.937,0.879 and 0.7 1 8,respectively,with optimal thresholds of 50,70 and －0.43,sensitivity and specificity of 90.9% and 88.5%,77.3% and 88.9%,and 61.5% and 77.8%.Conclusion The histogram analysis of MRI images contributes to differentiate quantitatively between brain high-grade glioblastomas,primary lymphoma and metastatic tumor.
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Objective To investigate alterations of blood perfusion in subcortical regions in patients with Parkinson′s disease (PD) by three dimentional arterial spin labeling (ASL) magnetic resonance imaging (MRI). Methods Thirty patients with PD and 40 control subjects were recruited from the inpatient and outpatient of the Department of Neurology of Northern Jiangsu People′s Hospital during October 2014 to October 2016, and routine brain MRI and 3D pseudo?continuous pulse ASL were performed on all the subjects. The cerebral blood flow (CBF) maps derived from 3D ASL were coregistered to the Montreal Neurological Institute brain space. The stereo?templates of bilateral caudate nucleus, putamen nucleus, globus pallidum and thalamus from Anatomical Automatic Labeling were used as region of interest (ROI) to exstract absolute CBF values in these subcortical regions, respectively. The CBF ratio (rCBF) values represented by individual whole brain CBF divided by each of the regional CBF were also calculated in consideration of the difference between individual whole brain CBF. The CBF and rCBF values were compared respectively between groups by one?way analysis of variance. Results The subcortical CBF values (ml·100 g-1·min-1) for each ROI in PD (caudate nucleus (left: 35.32±6.47, right: 36.17±7.07), globus pallidum (left: 40.42 ± 5.83, right: 40.18 ± 5.70), putamen nucleus (left: 41.97 ± 6.12, right: 42.91 ± 6.43) and thalamus (left: 46.58 ± 7.71, right: 49.11 ± 7.10)) were significantly lower than that in the control group (caudate nucleus (left: 41.38±7.05,right: 41.63±6.85), globus pallidum (left: 45.65±8.35,right: 45.53±8.94), putamen nucleus (left: 48.49±8.78, right: 48.99±8.88) and thalamus (left: 54.32±11.94,right: 56.21±11.98), F=13.58, 10.56, 12.11, 10.06, 8.59, 8.23, 9.57, 8.30, P=0.000, 0.002, 0.005, 0.005, 0.001, 0.002, 0.003, 0.005, respectively ). The whole brain mean CBF values of each subject were also extracted and compared bewteen groups, and mean CBF values (ml·100 g-1·min-1) in PD patients (42.14±9.61) decreased significantly than those in the control group (51.59±9.67, F=16.42, P<0.01), and there was a 18.31% decrement in whole brain mean CBF in the patient group. However, rCBF values for almost all subcortical ROIs of the patients significantly increased when compared with the control group. Conclusions The decreased absolute cerebral blood perfusion involved not only subcortical regions, but also the whole brain level in the course of PD. The CBF metabolism in patients with PD may have been redistributed, with relative hyperperfusion in the subcortical brain regions contrast to the whole brain perfusion level of patients themselves.
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Objective To explore the value of single source dual energy CT for quantitative measurement of liver fat fraction in the rabbit model of nonalcoholic fatty liver disease(NAFLD).Methods Thirty male New Zealand rabbits were randomly divided into five groups.Six rabbits were fed with standard chow as a control group for 3 weeks.TwentyGfour rabbits were divided into four groups and fed with highGfat, highGcholesterol diet to reach different stage of NAFLD model for 1 ,3 ,4 and 8 weeks respectively before dualGenergy CT scanning.1 40 keV polychromatic CT values (QC),70 keV monochromatic CT values (Mono 70 keV),slope,effective atomic number (EffectiveGZ)and fat concentration based on dualGenergy CT fat decomposition (Fat/Water)were measured.Liver samples were obtained to measure the fat fraction and staged according to Burnt staging system.Correlations between different CT indexes and fat fraction were analyzed.ROC was used to evaluate the diagnosis efficacy of different parameters.Results Correlation between fat concentration based on dualGenergy CT fat decomposition and fat fraction (r＝0.936)was better than that between 140 keV polychromatic CT values (r＝－0.838)and 70 keV monochromatic CT values (r＝－0.906),as well as effective atomic number (r＝－0.858)and slope (r＝0.863).In terms of diagnostic performance of material decomposition fat imaging,the values of area under the curve were 0.944 (stage 0 vs.stage 1 or more severe),0.995 (stage 1 or less severe vs.stage 2 or more severe)and 1 (stage 2 or less severe vs.stage 3)with optimal cutoff values of 59.310,99.5 17 and 22 3.02 3 mg/cm3 ,respectively.Conclusion The dualGenergy CT can quantitatively measure liver fat concentration as a noninvasive surrogate bioGmarker in the rabbit model of nonalcoholic fatty liver disease.DualGenergy CT derived material decomposition fat images can provide more diagnostic information at the early stage of NAFLD.
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Objective To evaluate the value of low-dose spectral CT imaging combined with ASIR recon-struction in differenting peripheral lung cancer from inflammatory mass. Methods We retrospectively analyzed the imaging data of 147 cases with 165 pulmonary nodules or masses underwent enhanced CT scans with spectral imag-ing mode from June 2015 to May 2016. Spectral curves,normalized slope rates,iodine-water concentration were measured on the lesions in arteral phase images. The differences of the spectral characteristic parameters were eval-uated statistically by indepengdent samples t test. Results Among 165 pulmonary nodules or masses,including 68 inflammatory mass and 97 peripheral lung cancer. In the arterial phase,the iodine concentration,water concentra-tion and normalized spectral curves rates of peripheral lung cancer were 10.93 ± 5.12,1033.96 ± 9.74,0.998 ± 0.66,which was obviously higher than those in inflammatory mass in 5.29 ± 0.96,1028.85 ± 9.31,0.620 ± 0.16. There were significant difference between peripheral lung cancer and inflammatory mass(0.000 ,0.008 ,0.001 in P values). Conclusion The iodine concentration,water concentration and normalized spectral curves rates has high value for differential diagnosis of peripheral pung cancer and pneumonia mass in the arterial phase using low-dose spectral CT imaging combined with ASIR reconstruction.
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Objective To investigate the degradation characteristics of the large-scale brain functional networks during aging by functional magnetic resonance imaging measurement and explore its intrinsic mechanism.Methods 40 healthy subjects including 20 elderly persons [mean aged(72.4 ±4.6)years] and 18 young persons [mean aged(23.9± 1.8) years] were enrolled in this study.All subjects underwent functional MRI scanning at blood oxygenation level-dependent contrast resting state.Four canonical resting-state networks,including the default mode network (DMN),dorsal attention network (DAN),executive control network (ECN),salience network,and visual network,were extracted by the seed zone and double regression methods.The functional connectivities in these canonical networks were compared between the young and elderly persons.Results Compared with young persons,the elderly showed the distinct and disruptive alterations in the large-scale aging-related resting brain networks.The impairment of ECN was the most serious,followed by the impairment of DAN.The salience networks and DMN showed relatively limited functional connectivity disruption.The networks associated to higher-order brain functions were impaired,while the visual network,which served as a network related to low-order brain functions,had no significant change.Conclusions The aged brain in healthy subjects is characterized by organized change in networks,and the selective impairments of large-scale brain networks were more significant in the networks associated to higher-order brain functions as compared with the networks related to low-order brain functions.
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Objective To observe the formation process with 3.0 T MRI dynamically, and to discuss the feasibility of molecular imaging studies on restenosis. Methods The models were built with balloon (2.0 F) injury which were separated into restenosis group (n=48) and control group (n=48). Zero h, 24 h, 1 week, 2 week, 4 week and 8 week after surgery, 3.0 T MRI scanning (T1WI, T2WI, PDWI) was performed respectively, the vascular of injured side were obtained for HE staining to observe the pathological changes, to analyze the measurement of neointimal area (IA), intimal proliferation index (IHI), lumen area (LA) and stenosis rates, correlation between HE staining measurements and MR images were analyzed. Two weeks after the injury, the restenosis model of rats (n=8) and control rats (n=8) were injected ultrasmall superparamagntiec iron oxide (USPIO,1 mmol/kg) by tail vein, respectively. 3.0 T MRI scanning (T2WI) was underwent at 0 h and 24 h after injection, the change of the arterial wall T2 signal was quantitatively analyzed and the relative signal intensity (rSI) and relative change rate (rSIC) of the vessel wall were calculated. Reference to MRI images, corresponding line segments were taken for Perl's blue staining and immunohistochemically staining of macrophages. One-way ANOVA, Pearson and t test were used for statistical analysis. Results In the early?term (0 h,24 h), the wall and surrounding high signal organization boundary was not clear, there was no obvious morphological change of the lumen. In the medium?term (1, 2 week), signal of the injured wall increased with different extents, wall thickening and luminal narrowing was progressive, the inwall was coarse. In the later?term (4, 8 week) wall signal got slightly lower, wall thickness, lumen change were not significant, the wall area and LA were significantly associated with pathologic measurement result (r value were 0.978, 0.732; P0.05). rSI was 1.582±0.051 after the injection of USPIO, then 24 h after injection of USPIO, T2 signal of the vessel wall was reduced significantly, rSI was 1.260 ± 0.088, rSIC was (-20.249 ± 6.489) % with statistical difference (t value was 8.924,P0.05). Perl's staining combined with immunohistochemical staining confirmed that the iron particles were taken by the macrophage's phagocytosis just in the neointimal. Conclusion 3.0 T MRI is capable of demonstrating the vessel wall and lumen changes dynamically, and the measurements are correlated with pathological results. USPIO can be consumed by macrophages in the neointimal, resulting in T2 signal of the vessel wall decreased significantly.
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Objective To compare the iodine contrast agent dosage,radiation dose and image quality in CT pulmonary angiogra-phy (CTPA)with low tube voltage and high tube current in 64-slice spiral CT.Methods 60 patients with suspected pulmonary em-bolism in our hospital were randomly chosen and divided into three groups:Group Ⅰ:20 patients,using 120 kV,180 mA,contrast dose of 70 mL.Group Ⅱ:20 patients,using 100 kV,280 mA,contrast dose of 50 mL.Group Ⅲ:20 patients,using 80 kV,automat-ic tube current modulation techniques (300-500 mA),comparative dose of 30 mL.CT values and image noise of three pulmonary central areas and a segment branch were measured in each group.Objective indicators,subjective image quality assessment,CT dose index volume (CTDIvol),dose-length product (DLP)and effective absorbed dose (ED)were compared in three groups to evaluate the value of low kV,high mA with low-contrast dose in CTPA.Analysis of variance and t-test was used for data analysis.Results Compared with those of the standard method of CTPA,all pulmonary dry in two groups of low dose were well displayed.There was no statistical significance between each two groups in image quality score (P > 0.05),but was statistical significance in CT values, noise,SNR and CNR (P < 0.01).The CT radiation dose,CTDIvol and DLP of Group Ⅱ and Group Ⅲ were significantly lower than those of Group Ⅰ (P < 0.01).Conclusion Compared with traditional methods,low dose contrast agent injections under 80 kV could reduce the dose of contrast agent and the effect of hardening artifacts due to contrast agent in superior vena cava on right pul-monary artery.It is helpful to reduce the risk of contrast induced nephropathy and reduce patients’exposure to X-ray radiation.
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Objectives To explore the value of Silenz MRA in the follow-up assessment of intracranial aneurysms embolization. Methods Fifteen patients underwent coiled embolization were prospectively collected. Silenz and time of flight MRA (TOF MRA) were performed on the same day as DSA examination. Two neuro-radiologists scored the structures of peripheral vascular with a 4-score grading system and evaluate embolism status (two-grade montreal scale). The scores of vascular structures were compared using Wilcoxon signed rank tests. Weighted Kappa statistics was used to assess the inter-observer agreement on each MRA scoring, the inter-modality agreement between MRA and DSA, the inter-modality agreement between the MRA methods. Results There were 11 cases with complete occlusion, 4 cases with residual aneurysm revealed by DSA. For depiction, Silenz MRA was significantly better than TOF MRA [(3.50 ± 0.62) vs. (3.00 ± 0.63), Z=-3.12, P=0.002]. Inter-modality agreement of Silenz MRA and DSA was excellent (Kappa=0.82), while the agreement of TOF MRA and DSA was moderate(Kappa=0.60). Inter-modality agreement between Silenz MRA and TOF MRA was good (Kappa=0.76). Conclusions Silenz MRA is superior to TOF MRA for depiction of vascular structures and evaluation of embolism status, which is highly related with DSA. It has the value in the postoperative follow-up evaluation.
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Objective To evaluate the anatomical and developmental characteristics of inner ears and establish a normalized inner ear multi-slice computed tomography (MSCT)measurement standard.Methods The raw data of 81 normal head MSCT cases were amplified and reconstructed in inner ear areas and multi-plannar reformation (MPR)was used to measure diameters of the inner ears.-test was used to inspect the difference between sides and genders,one-way analysis of variance was adopted for different age groups. Significance level α=0.05,P <0.05 was considered statistically significant.Results There was no statistical significance in measured values of inner ears in different age groups,genders and sides.Not all the shapes of bony semicircular canals were completely circu-lar or elliptical.In lumen,posterior semicircular canal was maximal and superior semicircular canal was minimal.In height,posterior semicircular canal was maximal and lateral semicircular canal was minimal.In width,superior semicircular canal was maximal and lateral semicircular canal was minimal.Conclusion Measurement specifications of inner ear on MSCT are initial established,main structures of inner ear can be clearly displayed by post-processing of head MSCT raw data.
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Objective To compare the efficacy of spectral CT imaging and 64 slice CT in assessment of carotid artery atherosclerotic plaque.Methods Thirty-eight patients with carotid plaque were detected retrospectively in this study (plaque,n=46) by using spectral CT.The composition of atherosclerotic plaque was measured by iodine-based images,lipid-based images with spectral CT imaging.Intraplaque hemorrhae,lipid components were also evaluated on spectral CT imaging and compared with pathology and specimen.Statistical comparison was performed with the Kappa value,independent-sample t test and exact test.Results The degree of carotid artery stenosis was (63.3 ±3.1)％ on spectral CT imaging whereas (61.6 ± 3.8) ％ on 64 slice CT.Two imaging modalities were in good consistency in evaluation of the degree of stenosis (Kappa=0.993,P＜0.01).There was no statistical difference in detecting fibrous cap rupture on spectral CT imaging and 64 slice CT (12 plaques vs 11 plaques,respectively,P＞0.05).Furthermore,spectral CT imaging showed 11 plaques within intraplaque hemorrhage,however,no case was found on 64 slice CT (P＜0.05).The plaque iodine concentration were (6.365 ± 1.937) and (1.573 ±0.776) mg/cm3 with or without internal hemorrhage(t=16.39,P＜0.05).Spectral CT imaging showed 9 plaques within intraplaque liquid whereas only 2 plaques showed intraplaque liquid on 64 slice CT (P＜0.05).Twenty-eight plaques within calcification in the plaque were found on spectrl CT imaging and 27 on 64 slice CT(P＞0.05).Conclusion Spectral CT imaging is a reliable tool in detecting intraplaque hemor-rhage and liquid component.
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Objective To investigate the Adamkiewicz artery visualization using gemstone spectral CT angiography (CTA) with optimal monochromatic technique.Methods The prospective study was approved by the local institutional review board,and written informed consents were obtained for all the examinations.The successive 58 patients with suspected aortic aneurysm or dissection underwent aortic gemstone spectral CTA.They were divided into two groups based on the different reconstruction protocols:A,optimal monochromatic reconstruction;B,polychromatic reconstruction.Visualization rate of Adamkiewicz artery in two groups were recorded.Objective(measure CT value of the descending aorta and calculate signal-to-noise ratio [CNR]) and subjective (score of Adamkiewicz artery visualization) were evaluated.Paired samples t,Chi-square and Mann-Whitney U test were used for statistical analysis.Results CT value of descending aorta and CNR of group A [(568.4 ± 57.5)HU and (52.3 ± 8.1)] were significantly higher than group B[(346.2 ± 48.6)HU and (26.7 ± 3.7)] (t=12.70 and 15.20,P＜0.01).The visualization rate of Adamkiewicz artery in group A (94.8％,55/58) was higher than B (82.8％,48/58;x2=4.20,P=0.04).The score of group A (55 cases,3.9±0.8) was significantly higher than the group B (48 cases,3.4±1.0)(Z=-2.40,P=0.02).Conelusion Gemstone spectral CTA with optimal monochromatic reconstruction can improve the visualization efficiency and quality of the Adamkiewicz artery compared with routine polychromatic reconstruction protocol.
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Purpose To summarize the CT features and clinical characteristics of atypical primary fallopian tube cancer (PCFT) and ovarian cystadenocarcinoma (OCA), in order to improved the diagnosis. Materials and Methods CT findings and clinical data of 12 patients with atypical PCFT (PCFT group) and 20 patients with OCA (OCA group) were retrospectively studied. All patients were confirmed by pathology. Serum CA125 level, clinical characteristics and CT features of two groups were compared. Results Serum CA125 level of PCFT group and OCA group were (486.13±23.89) U/ml and (1606.94±62.86) U/ml, respectively. There was statistic difference between the two groups (P0.05). Conclusion Clinical findings of serum CA125 level, vaginal bleeding, and vaginal discharge combine with imaging findings of diameter of the ovarian vein in the affected side, diameter of ipsilateral round ligament of uterus, tumor volume, CT values of the mass in venous and delay phase would be the key points for differential diagnosis of PCFT and OCA.
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Objective To evaluate the differences in image quality and radiation dose in the neck CTA between low tube voltage scanning method combined with exact calculation of contrast dosage and conventional scanning methods.Methods Ninety patients who had undergone neck CTA examination from October 2012 to June 2013 were prospectively selected to perform study.Patients were randomly divided into Group A,B and C,each with 30 cases.Tube voltage and contrast amount were,respectively,120 kV and 70-80 ml for Group A (conventional group),100 kV and exact calculation for Group B,80 kV and exact calculation for Group C.Using ANOVA test,radiation dose,contrast amount,CNR were statistically analyzed among three groups.Subjective evaluations were made of image quality by two experienced radiologists based on a 5-point system.Results The effective doses in Group B and C were (4.5 ± 0.7) mSv and (2.1 ± 0.4) mSv,respectively,significantly lower than (6.6 ± 0.9) mSv in Group A,with statistically significant difference(F =72.4,P ＜ 0.05).The amounts of contrast were significantly lower in Group B and C than that in Group A,which respectively were (73.2 ± 8.2) ml for Group A and (48.2 ± 5.1) for Group B and (48.6 ± 5.4) ml for Group C,with statistically significant difference (F =56.8,P ＜ 0.05).CNRs increased respectively by 42.2％ in Group B and by 42.2％ in Group C compared with Group A,with statistically significant difference (F =72.6,P ＜ 0.05).Venous artifact images were found in 10 patients of Group A,having different effects on image quality,whereas in Group B and C,there were not vein artifacts to found.Conclusions The low tube voltage (80 kV) scanning method combined with exact calculation of contrast features not only significantly lower radiation dose and lower contrast amount used,but also improved image quality in comparison with conventional method.
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The clinical characteristics and radiological data of 6 cases of sacral agenesis in one single family were analyzed and a literature review was performed.On magnetic resonance imaging (MRI),all of them presented with a partial absence of sacral vertebra,including associations with lumbar abnormalities (n =2) and sacral agenesis (n =2).One case presented with fourth/fifth lumbar vertebra bone fusion and fifth lumbar/first sacral vertebra bone fusion.On radiology,4 cases had concurrent scoliosis.None of them had tethered cord,diastematomyelia or meningocele.The understanding of sacral agenesis may be improved after reviewing and summarizing clinical features and radiological findings.
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Objective To investigate the differential diagnostic features of subtpes of renal cell carcinoma (RCC) using CT scan.Methods The CT appearances of 53 RCCs,including 28 clear cell RCCs (CCRCC),6 Xp11.2 /TFE RCCs (Xp11.2 /TFE RCC),7 collecting ducts RCCs (CDC),12 chromophobe RCCs (CRCC),were retrospectively analyzed and compared with finding of pathology.Dynamic contrast-enhanced CT (DCE-CT) was conducted in each case after intravenous administration of contrast agent,and the data was analyzed by AVONA and LSD text.Results On unenhanced and enhanced CT,most CCRCCs and CDCs showed heterogeneous density (23/28,6/7),with necrosis (21/28,6/7),and most Xp11.2/TFE RCCs,CRCCs showed homogeneous density(5/6,8/12).Most CCRCCs,Xp11.2/TFE RCCs and CRCCs had clearly boundaries with well demonstrated at enhanced CT delayed phase (25/28,6/6,10/12),CDCs had unclearly boundaries (6/7),and most CCRCCs had lymph node or other metastasis (19/28).A phenomenon of quick staining and quick fainting was observed in CCRCCs.Xp11.2/TFE RCCs,CDCs,CRCCs showed delayed enhancement.On unenhanced CT,the Xp11.2/TFE RCC attenuation was greater than CCRCC,CDC,CRCC and normal renal cortex (53.7±4.1 vs 45.8±3.6 vs 41.4±2.4 vs 47.7±3.6 vs 41.5±5.1,F=5.458,P＜0.01,respectively).The enhancement degree was highest for CCRCCs,lowest for CDCs,and intermediate for Xp1 1.2/TFE RCCs and CRCCs.The enhancement degree of Xp1 1.2/TFE RCC was higher than that of the CDC and CRCC (P＜ 0.01).The enhancement degree of Xp11.2/TFE RCC and CRCC were higher than that of the normal renal medulla at cortical and medullary phases (P＜0.01),but lower than that of the renal medulla on delayed phase (P＜0.01).The enhancement degree of CDC were lower than that of the normal renal cortex and medulla on cortical,medullary and delayed phases (P＜0.05).Conclusions CT could distinctly show imaging features of CCRCC,Xp1 1.2/TFE RCC,CDC and CRCC,which were related to their pathological characteristics,and these features were helpful in predicting a specific subtype of RCC.
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Purpose To implement lower artery angiography in patients with peripheral arterial occlusive disease, and to investigate the feasibility of lower extremity gemstone spectral CT angiography in improving image quality.Materials and Methods Forty-eight patients suspected with lower extremity arterial occlusive diseases were randomly divided into research group and control group. Research group (24 cases) were carried out gemstone spectral CT angiography (CTA) scan and control group (24 cases) were scanned with multi-slice spiral CT (CTA). The CT value of the common iliac artery, popliteal artery and its branches was measured and contrast to noise ratio (CNR) were calculated in both groups. The images were evaluated independently by 2 senior physicians based on a 5-level evaluation standard.Results The CT value of common iliac artery, popliteal artery, anterior tibial artery and the CNR in research group were all higher than those in control group (t=8.7, 7.9, 12.6 and 17.2,P<0.01), but the background noise was lower than that in control group (t=1.5,P<0.01). The scores of two image quality accessed by physician 1 and 2 were 110:90 and 111:93 respectively with statistical difference (Z=-7.6 and-8.0, P<0.01).Conclusion The image obtained by gemstone spectral CT optimal single energy image technique is much better than that by conventional multi-slice spiral CT in lower extremity angiography.
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<p><b>BACKGROUND</b>There are relatively few reports focusing on clinical and multi-slice CT (MSCT) imaging findings of mucinous tubular and spindle cell carcinoma (MTSCC). Our study aimed to characterize the clinical and MSCT imaging features of MTSCC.</p><p><b>METHODS</b>The imaging findings in 17 patients with MTSCC by MSCT were retrospectively studied. MSCT was undertaken to investigate tumor location, size, density, cystic or solid appearance, calcification, capsule sign, enhancement pattern, and retroperitoneal lymph node metastasis.</p><p><b>RESULTS</b>Tumors (mean diameter, (3.9 ± 1.7) cm) were solitary (17/17), solid (16/17) with cystic components (5/17), had no calcifications (14/17), had a poorly defined margin (14/17), were centered in the medulla (15/17), compressed the renal pelvis (7/17), and neither lymph node nor distant metastasis was found. The attenuation of MTSCC tumors was equal to that of the renal cortex or medulla on unenhanced CT (32.3 ± 2.6, 36.3 ± 4.6, 33.2 ± 3.9, respectively, P > 0.05), while tumor enhancement after administration of a contrast agent was lower than that of normal renal cortex and medulla during all phases (P < 0.05).</p><p><b>CONCLUSION</b>MTSCC tends to be a solitary, isodense mass with poorly defined margin arising from the renal medulla with enhancement less than the cortex and medulla during all phases.</p>