Abstract MR DWI-PWI mismatch has been established as a reliable biomarker for ischemic penumbra in acute ischemic stroke(AIS) patients. Texture analysis has demonstrated its ability to predict DWI-PWI mismatch of AIS within 24 hours. The current study was to investigate whether texture analysis of diffusion ADC maps can predict the existence of the DWI-PWI mismatch in the delayed imaging AIS patients. MR diffusion ADC maps of 82 patients with acute cerebral infarction beyond 24 hours from ischemic stroke onset were analyzed (41 with DWI-PWI mismatch and 41 without DWI-PWI mismatch). 2D Texture features were extracted to develop models for predicting the existence of DWI-PWI mismatch. 30 texture features were selected with the texture analysis software, and reduced to 10 with Lasso method and 3 with stepwise logistic regression. An equation was developed with these three features with acceptable diagnostic performance (sensitivity: 80.5%(65.1%~91.2%, specificity: 75.6%(59.7%~ 87.6%), PPV: 76.7%(61.4%~88.2%), NPV 79.5%( 63.5%~90.7%), AUC: 0.859(0.777~0.941), misclassification rate: 21.95%). During the leave-one-out validation, the equation is relatively stable, with 4 case changed the predicted status. 2D texture analysis of diffusion ADC maps can be used to predict the existence of DWI-PWI mismatch in the delayed imaging population. The logistic regression-based equation is a promising predicting method.

Background: Odor perception is highly dependent on respiration, however, the asynchronization between inspiration and odor delivery results in a decreased activation and hemodynamic response function (HRF) curve in olfactory functional MRI (fMRI). This study aimed to investigate the effect of a data post-processing method to minimize the asynchronization and consequently improve the olfactory activation and HRF curve and compare it between different TRs (3 s and 1 s).New method: A new data post-processing method of respiration correction based on olfactory perception was investigated. Comparison with existing methods: The odor stimuli of olfactory fMRI were mostly based on odor deliveries. But for the reason of respiration, the time of olfactory perception might be a little different. The actual onset time and duration of odor stimuli were modified based on the respiration data.Results: For 3 s TR data, an increased number of activated voxels and higher HRF curves response height were obtained with the respiration correction method in the primary olfactory cortex (POC) (P = 0.034 and 0.009) and insula (P = 0.024 and 0.001), compared with the uncorrected method. But the activated voxels and response height of the anterior cingulate cortex (ACC) did not differ between uncorrected and respiration correction methods (P = 0.102 and 0.200). The time to peak of the HRF curve was shorter with the respiration correction method in all ROIs (all P < 0.05), compared with the uncorrected method. Whereas there were no significant differences between the uncorrected and corrected results for 1 s TR data.Conclusions: The post-processing method of respiration correction could effectively minimize the asynchronization between respirations and odor deliveries, and improve the activations and HRF curves for a routine 3 s TR olfactory fMRI data.

目的:探讨不同类型先天性耳畸形的构成比例及高分辨率CT(HRCT)和磁共振成像(MRI)对先天性耳畸形的诊断价值.方法:回顾性分析2020年1月至2023年1月期间,在我院影像科诊断为先天性耳畸形患者的影像学资料,共74人,98耳.其中,69例行HRCT扫描,6例行MRI扫描.分析各种先天性耳畸形的构成比例并探讨HRCT和MRI对耳畸形的诊断价值.结果:74例先天性耳畸形病例中,单纯外耳畸形11例;单纯中耳畸形7例;外耳畸形合并中耳畸形16例;外耳畸形合并内耳畸形1例;中耳畸形合并内耳畸形2例;外耳、中耳及内耳混合畸形2例.结论:外耳、中耳畸形常同时发生,内耳畸形伴发外耳或中耳畸形较少.HRCT对骨质结构显示清晰,是目前先天性耳畸形的首选检查方法,MRI可用于对膜迷路和神经结构的显示,HRCT和MRI结合能清晰显示耳的解剖结构,是耳蜗植入术前必要的影像学检查.

To establish and validate a CT radiomics model for prediction of induction chemotherapy (IC) response and progression-free survival (PFS) among patients with locally advanced hypopharyngeal carcinoma (LAHC). One hundred twelve patients with LAHC (78 in training cohort and 34 in validation cohort) who underwent contrast-enhanced CT (CECT) scans prior to IC were enrolled. Least absolute shrinkage and selection operator (LASSO) was used to select the crucial radiomic features in the training cohort. Radiomics signature and clinical data were used to build a radiomics nomogram to predict individual response to IC. Kaplan–Meier analysis and log-rank test were used to evaluate ability of radiomics signature in progression-free survival risk stratification. The radiomics signature consisted of 6 selected features from the arterial and venous phases of CECT images and demonstrated good performance in predicting the IC response in both two cohorts. The radiomics nomogram showed good discriminative performance, and the C-index of nomogram was 0.899 (95 • CT radiomics can predict IC response and progression-free survival in hypopharyngeal carcinoma. • We combined significant radiomics signature with clinical predictors to establish a nomogram to predict individual response to IC. • Radiomics signature could divide patients into the high-risk and low-risk groups based on the PFS.

Purpose To establish and validate a radiomics signature for stratifying the risk of progression-free survival (PFS) in patients with locally advanced hypopharyngeal carcinoma (LAHC) undergoing induction chemotherapy (IC). Methods We extracted radiomics features from baseline contrast-enhanced computed tomography (CECT) images. We enrolled 112 LAHC patients (78 in the training cohort and 34 in the validation cohort). We used cox regression model and random survival forests variable hunting (RSFVH) algorithm for feature selection and radiomics signature building. The radiomics signature was established in the training cohort and tested in the validation cohort. We used the Kaplan-Meier analysis and log-rank test to evaluate the ability of radiomics signature in PFS risk stratification among patients with different IC responses and constructed a radiomics nomogram to predict individual PFS risk. Results The radiomics signature performed well in stratifying patients into highrisk and low-risk groups of progression in both the training and validation cohorts. The radiomics nomogram showed good discriminative ability for predicting PFS. Survival outcome analysis of subsets indicated that the radiomics signature performed well in stratifying the risk of PFS in patients with LAHC with different IC responses. Conclusions The radiomics signature was a pretreatment predictor for PFS in patients with LAHC who exhibited different responses to IC.

Neoadjuvant chemotherapy has become one of the important means for advanced hypopharyngeal carcinoma. So far, there is no effective index to predict the curative effect. To investigate the value of iodine map of dual-energy computed tomography (CT) in predicting the efficacy of neoadjuvant chemotherapy for hypopharyngeal carcinoma. A total of 54 hypopharyngeal carcinomapatients who underwent two courses of TPF neoadjuvant chemotherapy were recruited in this study. Three cases had a complete response (CR), thirty-six cases had a partial response (PR), eleven cases had stable disease (SD), and four cases had a progressive disease (PD) after the chemotherapy. All patients underwent a dual-source CT scan before chemotherapy and rescanned after chemotherapy. The normalized iodine-related attenuation (NIRA) of the mean of maximum slice and most enhanced region of lesion at arterial and parenchymal phase were measured: NIRA mean-A , NIRA max-A , NIRA mean-P , and NIRA max-P , respectively. Correlation analysis was conducted between different metrics of NIRA and the diameter change rate of lesions, and the curative effect was evaluated based on the receiver operating characteristic (ROC) curve. There were a significant correlation between NIRA mean-A , NIRA max-A , NIRA mean-P , NIRA max-P and the change rate of lesion’s maximum diameter (ΔD%) (all P < 0.01). The NIRA max-A , NIRA mean-P , NIRA max-P had significant differences between CR, PR, SD, PD groups, but NIRA mean-A did not reach a significant difference. All NIRA mean-A , NIRA max-A , NIRA mean-P , NIRA max-P had significant differences between effective (CR + PR) and ineffective (SD + PD) groups. The ROC analysis revealed that NIRA mean-P had the largest AUC and prediction efficacy (AUC = 0.809). Dual-energy CT iodine map could predict the efficacy of neoadjuvant chemotherapy and provides imaging evidence to assist in treatment decisions for hypopharyngeal carcinoma patients.

BACKGROUND:Despite its wide adoption in stroke imaging, the diffusion-weighted imaging (DWI) lesion is heterogeneous. The emerging diffusion kurtosis imaging (DKI) has been postulated to resolve the graded DWI lesion. PURPOSE:To determine the perfusion characteristics of the central infarction core, kurtosis/diffusion mismatch, and peripheral regions. MATERIAL AND METHODS:Patients with acute ischemic stroke underwent DWI, DKI, and perfusion-weighted imaging (PWI) scans. The patients were divided into mean kurtosis (MK)/mean diffusivity (MD) match and mismatch groups. Perfusion parameters were measured in the MK/MD lesion and peripheral areas in the MK/MD match group. We also analyzed perfusion status in the MK/MD lesion mismatch area for the mismatch group. RESULTS:A total of 40 eligible patients (24 MK/MD match and 16 MK/MD mismatch) were enrolled in the final data analysis. The MTT and TTP progressively decreased, while the cerebral blood flow (CBF) and cerebral blood volume (CBV) increased from the central to peripheral areas. In addition, CBF in the MK/MD mismatch region was significantly higher than that in the central region (P < 0.05), but similar to the peripheral region. Furthermore, CBV in the MK/MD mismatch region did not differ significantly from that of the central region, but both were significantly lower than that of the peripheral area (P < 0.05). CONCLUSION:The MK/MD mismatch region had blood flow similar to the peripheral region but with a reduced blood volume, indicating that it was less ischemic from the infarction core, albeit insufficient collateral circulation.

Objectives. The respiration could decrease the time synchronization between odor stimulation and data acquisition, consequently deteriorating the functional activation and hemodynamic response function (HRF) in olfactory functional magnetic resonance imaging (fMRI) with a conventional repetition time (TR). In this study, we aimed to investigate whether simultaneous multislice (SMS) technology with reduced TR could improve the blood oxygen level-dependent (BOLD) activation and optimize HRF modeling in olfactory fMRI. Methods. Sixteen young healthy subjects with normal olfaction underwent olfactory fMRI on a 3T MRI scanner using a 64 channel head coil. FMRI data were acquired using SMS acceleration at three different TRs: 3000 ms, 1000 ms, and 500 ms. Both metrics of BOLD activation (activated voxels, mean, and maximum t -scores) and the HRF modeling (response height and time to peak) were calculated in the bilateral amygdalae, hippocampi, and insulae. Results. The 500 ms and 1000 ms TRs both significantly improved the number of activated voxels, mean, and maximum t -score in the amygdalae and insulae, compared with a 3000 ms TR (all P < 0.05 ). But the increase of these metrics in the hippocampi did not reach a statistical significance (all P > 0.05 ). No significant difference in any BOLD activation metrics between TR 500 ms and 1000 ms was observed in all regions of interest (ROIs) (all P > 0.05 ). The HRF curves showed that higher response height and shorter time to peak in all ROIs were obtained at 500 ms and 1000 ms TRs compared to 3000 ms TR. TR 500 ms had a more significant effect on response height than TR 1000 ms in the amygdalae ( P = 0.017 ), and there was no significant difference in time to peak between TR 500 ms and 1000 ms in all ROIs (all P > 0.05 ). Conclusions. The fast image acquisition technique of SMS with reduced TR could significantly improve the functional activation and HRF curve in olfactory fMRI.

目的 探讨嗅觉功能磁共振成像(fMRI)评估对非痴呆老年人认知下降的预测价值.资料与方法 纳入非痴呆老年人89例,前瞻性随访3年,最后78例完成随访.根据认知水平较基线是否下降分为认知下降组34例和认知未下降组44例.使用嗅觉fMRI评估嗅觉功能,参数为初级嗅觉皮层(POC)和颞上回(STG)的激活体素数.结果 基线时,认知下降组POC区激活体素数低于认知未下降组(67.76±88.38比126.57±131.27;t=-2.359,P<0.05),两组STG激活体素数无显著差异(121.56±183.93比139.75±233.47;t=-0.373,P>0.05).认知下降组第3年随访时POC激活体素数仍低于认知未下降组(55.00±70.24比118.35±125.31;t=-2.827,P<0.01).基线时,POC区激活体素数预测非痴呆老年人认知下降的受试者工作特征曲线下面积为0.641(P<0.05),临界值为78.5,敏感度为56.8％,特异度为73.5％;而基线时的STG激活体素数对非痴呆老年人认知下降无预测价值(P>0.05).结论 嗅觉fMRI评估可客观评价嗅觉功能,可能是非痴呆老年人3年后发生认知功能下降的预测因素.

BACKGROUND AND PURPOSE:Leber hereditary optic neuropathy (LHON) is a disease maternally inherited from mitochondria that predominantly impairs the retinal ganglion cells and their axons. To identify whether occult brain white matter (WM) impairment is involved, a voxel-based analysis (VBA) of diffusion metrics was carried out in LHON patients with normal-appearing brain parenchyma. METHODS:Fifty-four symptomatic LHON patients (including 22 acute LHON with vision loss for ≤12 months, and 32 chronic LHON) without any visible brain lesions and 36 healthy controls (HCs) were enrolled in this study. VBA was applied to quantify the WM microstructural changes of LHON patients. Finally, the associations of the severity of WM impairment with disease duration and ophthalmologic deficits were assessed. RESULTS:Compared with the HCs, the average retinal nerve fiber layer (RNFL) thickness was significantly reduced in patients with chronic LHON, whereas it was increased in patients with acute LHON (p < 0.05, corrected). VBA identified significantly decreased fractional anisotropy widely in WM in both the acute and chronic LHON patients, including the left anterior thalamic radiation and superior longitudinal fasciculus, and bilateral corticospinal tract, dentate nuclei, inferior longitudinal fasciculus, forceps major, and optic radiation (OR; p < 0.05, corrected). The integrity of most WM structures (except for the OR) was correlated with neither disease duration nor RNFL thickness (p > 0.05, corrected). CONCLUSIONS:Occult primary impairment of widespread brain WM is present in LHON patients. The coexisting primary and secondary WM impairment may jointly contribute to the pathological process of LHON.

ObjectiveSubclinical abnormalities, including microangiopathy, swelling of nerve fibers, visual field abnormalities and visual functional impairments had been reported in Leber's hereditary optic neuropathy (LHON) carriers. The purpose of this study was to investigate microstructural changes of brain white matter in asymptomatic LHON carriers using DTI and tract-based spatial statistics (TBSS).MethodsDTI and neuro-ophthalmologic measurements were acquired in 14 LHON carriers and 15 gender- and age-matched healthy controls, and diffusion metrics, including fractional anisotropy (FA), axial (AD), radial diffusion (RD) and mean diffusion (MD) were calculated. Intergroup differences in diffusion metrics were compared regressing out potential nuisance covariates of age and gender. A correlation analysis was performed to test associations between abnormal neuro-ophthalmologic measures and diffusion metrics while controlling the effects of age and gender.ResultsCompared to healthy controls, LHON carriers showed a weak increase of thickness of the retinal nerve fiber layer (RNFL) of the right inferior quadrant (F=5.22, p=0.032, before multiple comparison correction). LHON carriers exhibited widespread decreased FA value (bilateral anterior thalamic radiations, bilateral corticospinal tracts, major and minor forceps, bilateral inferior fronto-occipital fasciculi and left superior longitudinal fasciculus), increased RD value (bilateral anterior thalamic radiations, bilateral corticospinal tracts, major and minor forceps, bilateral inferior fronto-occipital fasciculi, bilateral inferior longitudinal fasciculi, bilateral superior longitudinal fasciculi and bilateral uncinate fasciculi) and increased MD value (bilateral anterior thalamic radiations, bilateral corticospinal tracts, minor forceps, bilateral inferior fronto-occipital fasciculi, bilateral inferior longitudinal fasciculi, left superior longitudinal fasciculus and bilateral uncinate fasciculi). Moreover, these changed diffusion metrics were not correlated with age, gender, LHON mutations and retinal measures in LHON carriers.ConclusionOur results show microstructural alterations in brain white matter in asymptomatic LHON carriers, indicating that LHON-related genetic mutations themselves might result in occult white matter alterations in the brain.

Objective To summarize the computed tomographic (CT) manifestations of pulmonary aspergillosis after organ transplantation and compare different signs between pulmonary aspergillosis and bacterial pneumonia.Methods CT images of pulmonary aspergillosis (n =62) and bacterial pneumonia (n =68) in post-transplantation patients were reviewed.The signs were categorized with consolidation,mass,large nodule (≥1crn),small nodule and bud-in-tree pattern.Some detailed useful differentiating signs such as halo sign,air bronchogram sign,reversed halo sign,hypodensity sign and cavitation were also analyzed.Results CT patterns of pulmonary aspergillosis included consolidation,mass,large nodule,small nodule and bud-in-tree pattern.The most common was large nodule (75.8％),followed by consolidation (48.4％)and mass (29.0％).And small nodule (16.1 ％) and bud-in-tree (12.9％) patterns were concurrent.For consolidation pattern,the proportion of bacterial pneumonia (69.1％) was the larger;For mass pattern,the proportion of pulmonary aspergillosis (29.0％) was the larger.For large nodule pattern,there was no difference.The detail sign of large nodule in two groups had no difference In detailed signs of consolidation pattern,air bronchogram sign was more often seen in bacterial pneumonia while cavitation was more frequently found in pulmonary aspergillosis.In detailed signs of mass pattern,pulmonary aspergillosis often has single lesion (66.7％),cavitation (83.3％)and air crescent sign (77.8％) is more common.The proportion of halo sign was 30.7％.Conclusions CT manifestations of pulmonary aspergillosis are diverse after organ transplantation.There is some difference and yet overlap with bacterial pneumonia.

Purpose: To determine the possibility of a universal cut off value between benign and malignant lymph nodes in patients with tumour by Z-Score transformation method. Materials and methods: Diffusion weighted imaging, ADC measurements of malignant and benign lymph nodes of 6 studies (4 body parts), conducted for 5 times, in two institutions with variable technical details were analyzed in their original value as well as the standardized Z-Score value. The standardized Z-Score value was obtained by subtracting the population mean of the control group from an individual raw score and then dividing the difference by the population standard deviation of the control group. General cut off values were obtained by both Mega-analysis by receiver operator characteristic curve analysis, when data from the 6 studies were combined and Meta-analysis with weighting coefficients and cut off values of the six individual studies. Sensitivity, specificity and accuracy with cut offs from individual studies, meta-analysis and mega-analysis were calculated. Kappa WA was performed to assess the consistency of diagnostic WA accuracy, between optimized cut offs of individual studies and the proposed universal cut offs obtained from meta-analysis and mega-analysis. Results: The ADC values of benign and malignant lymph nodes are significantly different, but with large overlap across the studies. The overlap can be minimized by Z-Score transformation. The result of ROC analysis of the collective Z-Score transformed ADC values of 6 studies was superior to that of the collective original ADC values (sensitivity: 87.4% versus 67.2%, specificity: 90.5% versus 87.9%, accuracy: 89.6% versus 81.4%). The universal Z-Score cut off from Meta-analysis is also better than the original ADC cut off (sensitivity: 82.8% versus 76.3%, specificity 92.6% versus 62.9%, accuracy 89.6% versus 67.1%). Applied to the individual studies, the universal transformed Z-Score cut offs produced superior consistency with the individual optimal cut offs (individual and meta Z-Score: 0.7228-0.9793; individual and mega Z-Score: 0.7111-0.9169) compared with the universal original ADC cut offs (individual and meta ADC: 0.3030-1.0000; individual and mega ADC 0.3268-0.9618). Conclusion: Z-Score transformation could minimize inter-study variations due to heterogeneity of MR systems and sequence parameters, and provide a more consistent universal cut off value between benign and malignant nodes across studies.

目的:应用磁共振弥散张量成像(DTI)技术评价阿尔茨海默病(AD)患者脑白质的改变,分析部分各向异性(FA)和局域各向异性(GA)参数对AD患者脑白质损伤的诊断效率.方法:选取2014年8月-2015年8月确诊的AD患者12例(AD组),16例认知正常的健康老年志愿者为对照组,进行MRI常规扫描和DTI检查,测量上纵束、扣带束、胼胝体、内囊、额叶、项叶、颞叶、枕叶脑白质的FA、GA值.应用ROC曲线评价FA、GA参数检出AD患者脑白质损伤的诊断效率.结果:与对照组比较,AD组的扣带束后部FA、GA值降低;上纵束FA、GA值降低;顶叶白质FA、GA降低;额叶白质GA值降低;颞叶白质GA值降低;胼胝体压部GA降低,差异均有统计学意义.ROC曲线评价AD患者扣带束后部、上纵束、顶叶GA值曲线下面积较FA大,顶叶GA值对于AD患者脑白质损伤具有较高的诊断效率.结论:AD患者表现为选择性脑白质域性损害,扣带束后部、上纵束、胼胝体压部、额叶、颞叶、顶叶皮层下脑白质损伤,GA诊断AD病患者脑白质异常的效率比FA更佳.

Objective: To evaluate the changes of white matter in Alzheimer's disease(AD) patients by Magnetic resonance diffusion tensor imaging (DTI) and to analyze the diagnostic value of Fractional anisotropy (FA) and Geodesic anisotropy (GA) in detecting white matter abnormalities in AD patients. Methods: MRI routine scan and DTI were performed in 12 AD patients who were diagnosed from August 2014 to August 2015. 16 cognitively normal (NC) healthy elderly volunteers were enrolled, as control group, to this study. The FA and GA of superior longitudinal fasciculus, Cingulate, corpus callosum, internal capsule, frontal lobe, parietal lobe, temporal lobe and occipital lobe white matter were measured. The ROC curve was applied to analyze Fractional anisotropy (FA) and Geodesic anisotropy (GA) parameters to determine the diagnostic value in detecting white matter abnormalities in patients with AD. Results: Compared to the control group, the FA and GA values in the posterior cingulate were decreased, the FA and GA values of the superior longitudinal fasciculus were decreased, the FA and GA of the white matter in the parietal lobe were decreased, the GA value of the white matter in the frontal lobe was decreased, the GA value of the white matter in temporal lobe was decreased and the GA value of the splenium of corpus callosum was decreased. The differences were statistically significant. The area under the ROC curve was more than 0.700, which was larger than that of FA. Conclusion: AD patients usuaug show selective and regional damage in the posterior cingulated and the damage in superior longitudinal fasciculus, splenium of corpus callosum, frontal lobe, temporal lobe, parietal cortex and subcortical white matter lesions. The diagnostic value of GA in detection of white matter abnormalities in patients with AD was superior to FA. Key words: Magnetic resonance Imaging; Diffusion tensor imaging; Alzheimer’s disease; White matter

The anterior insula (AI) is the core hub of salience network that serves to identify the most relevant stimuli among vast sensory inputs and forward them to higher cognitive regions to guide behaviour. As blind subjects were usually reported with changed perceptive abilities for salient non-visual stimuli, we hypothesized that the resting-state functional network of the AI is selectively reorganized after visual deprivation. The resting-state functional connectivity (FC) of the bilateral dorsal and ventral AI was calculated for twenty congenitally blind (CB), 27 early blind (EB), 44 late blind (LB) individuals and 50 sighted controls (SCs). The FCs of the dorsal AI were strengthened with the dorsal visual stream, while weakened with the ventral visual stream in the blind than the SCs; in contrast, the FCs of the ventral AI of the blind was strengthened with the ventral visual stream. Furthermore, these strengthened FCs of both the dorsal and ventral AI were partially negatively associated with the onset age of blindness. Our result indicates two parallel pathways that selectively transfer non-visual salient information between the deprived "visual" cortex and salience network in blind subjects.

Objective To systemically evaluate the accuracy of CT and MR estimating whole liver volume with evidence based medicine methods.Method Published papers about whole liver volume estimation with CT or MR modality were searched in Cochrane library,MEDLINE,EMBASE,CMBdisc(China biology medicine disc) for English and Chinese abstracts.Inclusion criteria were formulated according to validity criteria for diagnostic research published by the Cochrane collaboration.Heterogeneity test of extracted data of Eligible papers was performed first to determine the appropriate statistical model used to pool the result.Finally,sensitivity and publish bias analysis was performed.Result Seventeen articles with 37 studies including 351 patients met the inclusion criteria.There was no heterogeneity between included studies (I2 =0％,Q =5.85,P =1).Fixed effect model was selected for the meta analysis and there was no statistically significant difference between true and radiological estimated whole liver volume (WMD =21.61 mL,95％ confidence interval:-6.33-49.57 mL,z =1.51,P =0.13).Sensitivity analysis revealed the result was robust which was not affected by excluding any of the included studies.Funnel plot and publish bias analysis showed no publish bias (t =-1.55,P=0.13).Conclusion CT and MR volume estimation is accurate for liver volume measurement,which provides important information for preoperative evaluation,postoperative monitoring and follow-up studies of other hepatic pathologies.aximum benefit to patients.

Objective To compare the accuracies of manual, semi-atuomatic and automatic whole liver volumetry with Meta-analysis. Methods Cochrane library, abstract databases (MEDLINE, EMBASE, and China biology medicine disc) and full text databases (Springer, OVID, CNKI, WanFang, et al) were searched for published papers on whole liver volumetry with CT or MR modality. Eligible papers were grouped according to the volumetry method (manual, semi-automatic and automatic) and evaluated for quality. With Meta-analysis package Meta of R software, group-wise Meta-analysis and comparison were performed. Results Sixteen articles including 315 patients met the inclusion criteria. There was no heterogeneity among included studies and there were no significant differences between radiologically estimated and true liver volumes of every group. The weighted mean difference was 12.098 mL (95%CI:-26.392~50.588 mL) in the manual group (P=0.538), 26.186 mL (95%CI:-29.842~82.213 mL) in the semi-automatic group (P=0.360) and 57.144 mL (95%CI:-10.770~125.059 mL) in the automatic group (P=0.099). The pooled results did not significantly differ among the three groups (Q=0.15, P=0.930). Conclusion The manual, semi-automatic and automatic liver volumetry are comparable in accuracy while the semi-automatic and automatic volumetry could greatly shorten measuring time, which are worthy of recommendation in clinical setting.

聚丙烯酰胺水凝胶(polyacrylamide hydrogel,PAAG)隆乳后女性易发生哺乳期积乳、感染,早期发现困难,易迅速进展为巨大脓肿,治疗不当可致伤口愈合困难及乳房变形等严重后果[1-2]。如何判定 PAAG 囊腔脓肿形成为外科医生面临的最大难题。常规影像学方法钼靶、B 超专注于解剖学形态,无法敏感、直观显示填充物成分、性状改变。尽管 MRI 在隆乳后乳腺随访及并发症检出方面的价值已得到广泛认可,但多数研究只关注常规 T1 WI、脂肪抑制 T2 WI。扩散加权成像(diffusion weighted imaging,DWI)能无创监测组织中水分子的自由扩散能力差异,敏感地反映囊性病变内容物信息,故该序列在检测PAAG 植入物(97.5%成分为自由水)成分、性状异常改变、尤其感染方面具有广泛应用潜力。本研究总结了应用 DWI 序列及表观扩散系数(ADC)值定量测量成功诊断的一组隆乳后哺乳期 PAAG 脓肿患者影像资料,以提高该序列在乳腺整形领域的筛查应用率及隆乳后乳腺脓肿的早期检出率。

To explore the correlation between increased brain iron deposition and brain atrophy in patients with haemodialysis and their correlation with clinical biomarkers and neuropsychological test. Forty two patients with haemodialysis and forty one age- and gender-matched healthy controls were recruited in this prospective study. 3D whole brain high resolution T1WI and susceptibility weighted imaging were scanned on a 3 T MRI system. The brain volume was analyzed using voxel-based morphometry (VBM) in patients and to compare with that of healthy controls. Quantitative susceptibility mapping was used to measure and compare the susceptibility of different structures between patients and healthy controls. Correlation analysis was used to investigate the relationship between the brain volume, iron deposition and neuropsychological scores. Stepwise multiple regression analysis was used to explore the effect of clinical biomarkers on the brain volumes in patients. Compared with healthy controls, patients with haemodialysis showed decreased volume of bilateral putamen and left insular lobe (All P < 0.05). Susceptibilities of bilateral caudate head, putamen, substantia nigra, red nucleus and dentate nucleus were significantly higher (All P < 0.05). The increased brain iron deposition is negatively correlated with the decreased volume of bilateral putamen (P < 0.01). Neuropsychological scores positively correlated with decreased volume of left insular lobe (P < 0.05). Dialysis duration was negatively associated with decreased volume of bilateral putamen (P < 0.05). Our study indicated increased brain iron deposition and dialysis duration was risk factors for brain atrophy in patients with haemodialysis. The decreased gray matter volume of the left insular lobe was correlated with neurocognitive impairment.