Susceptibility weighted imaging: Clinical applications and future directions

Susceptibility weighted imaging(SWI) is a recently developed magnetic resonance imaging(MRI) technique that is increasingly being used to narrow the differential diagnosis of many neurologic disorders. It exploits the magnetic susceptibility differences of various compounds including deoxygenated blood, blood products, iron and calcium, thus enabling a new source of contrast in MR. In this review, we illustrate its basic clinical applications in neuroimaging. SWI is based on a fully velocity-compensated, high-resolution, three dimensional gradientecho sequence using magnitude and phase images either separately or in combination with each other, in order to characterize brain tissue. SWI is particularly useful in the setting of trauma and acute neurologic presentations suggestive of stroke, but can also characterize occult low-flow vascular malformations, cerebral microbleeds, intracranial calcifications, neurodegenerative diseases and brain tumors. Furthermore, advanced MRI post-processing technique with quantitative susceptibility mapping, enables detailed anatomical differentiation based on quantification of brain iron from SWI raw data.

Three-dimensional time-of-flight magnetic resonance angiography combined with high resolution T2-weighted imaging in preoperative evaluation of microvascular decompression

BACKGROUND Neurovascular compression(NVC) is the main cause of primary trigeminal neuralgia(TN) and hemifacial spasm(HFS). Microvascular decompression(MVD) is an effective surgical method for the treatment of TN and HFS caused by NVC. The judgement of NVC is a critical step in the preoperative evaluation of MVD, which is related to the effect of MVD treatment. Magnetic resonance imaging(MRI) technology has been used to detect NVC prior to MVD for several years. Among many MRI sequences, three-dimensional time-of-flight magnetic resonance angiography(3D TOF MRA) is the most widely used. However, 3D TOF MRA has some shortcomings in detecting NVC. Therefore, 3D TOF MRA combined with high resolution T2-weighted imaging(HR T2WI) is considered to be a more effective method to detect NVC.AIM To determine the value of 3D TOF MRA combined with HR T2WI in the judgment of NVC, and thus to assess its value in the preoperative evaluation of MVD.METHODS Related studies published from inception to September 2022 based on PubMed, Embase, Web of Science, and the Cochrane Library were retrieved. Studies that investigated 3D TOF MRA combined with HR T2WI to judge NVC in patients with TN or HFS were included according to the inclusion criteria. Studies without complete data or not relevant to the research topics were excluded. The Quality Assessment of Diagnostic Accuracy Studies checklist was used to assess the quality of included studies. The publication bias of the included literature was examined by Deeks’ test. An exact binomial rendition of the bivariate mixed-effects regression model was used to synthesize data. Data analysis was performed using the MIDAS module of statistical software Stata 16.0. Two independent investigators extracted patient and study characteristics, and discrepancies were resolved by consensus. Individual and pooled sensitivities and specificities were calculated. The I_(2) statistic and Q test were used to test heterogeneity. The study was registered on the website of PROSERO(registration No. CRD42022357158).RESULTS Our search identified 595 articles, of which 12(including 855 patients) fulfilled the inclusion criteria. Bivariate analysis showed that the pooled sensitivity and specificity of 3D TOF MRA combined with HR T2WI for detecting NVC were 0.96 [95% confidence interval(CI): 0.92-0.98] and 0.92(95%CI: 0.74-0.98), respectively. The pooled positive likelihood ratio was 12.4(95%CI: 3.2-47.8), pooled negative likelihood ratio was 0.04(95%CI: 0.02-0.09), and pooled diagnostic odds ratio was 283(95%CI: 50-1620). The area under the receiver operating characteristic curve was 0.98(95%CI: 0.97-0.99). The studies showed no substantial heterogeneity(I2 = 0, Q = 0.001 P = 0.50).CONCLUSION Our results suggest that 3D TOF MRA combined with HR T2WI has excellent sensitivity and specificity for judging NVC in patients with TN or HFS. This method can be used as an effective tool for preoperative evaluation of MVD.

Evaluation of tumor response to antiangiogenic therapy in patients with recurrent gliomas using contrast-enhanced perfusion-weighted magnetic resonance imaging techniques:A meta-analysis

BACKGROUND It is of vital importance to find radiologic biomarkers that can accurately predict treatment response. Usually, the initiation of antiangiogenic therapy causes a rapid decrease in the contrast enhancing tumor. However, the treatment response is observed only in a fraction of patients due to the partial radiological response secondary to stabilization of abnormal vessels which does not essentially indicate a true antitumor effect. Perfusion-weighted magnetic resonance imaging(PWMRI) techniques have shown implicitness as a strong imaging biomarker for gliomas since they give hemodynamic information of blood vessels. Hence, there is a rapid expansion of PW-MRI related studies and clinical applications.AIM To determine the diagnostic performance of PW-MRI techniques including:(A)dynamic contrast-enhanced magnetic resonance imaging(DCE-MRI); and(B)dynamic susceptibility contrast magnetic resonance imaging(DSC-MRI) for evaluating response to antiangiogenic therapy in patients with recurrent gliomas.METHODS Databases such as PubMed(MEDLINE included), EMBASE, and Google Scholar were searched for relevant original articles. The included studies were assessed for methodological quality with the Quality Assessment of Diagnostic Accuracy Studies 2 tool. Medical imaging follow-up or histopathological analysis was used as the reference standard. The data were extracted by two reviewers independently, and then the sensitivity, specificity, summary receiver operating characteristic curve, area under the curve(AUC), and heterogeneity were calculated using Meta-Disc 1.4 software.RESULTS This study analyzed a total of six articles. The overall sensitivity for DCE-MRI and DSC-MRI was 0.69 [95% confidence interval(CI): 0.53-0.82], and the specificity was 0.99(95%CI: 0.93-1) by a random effects model(DerSimonianeeLaird model). The likelihood ratio(LR) +, LR-, and diagnostic odds ratio(DOR)were 12.84(4.54-36.28), 0.35(0.22-0.53), and 24.44(7.19-83.06), respectively. The AUC(± SE) was 0.9921(± 0.0120), and the Q* index(± SE) was 0.9640(± 0.0323).For DSC-MRI, the sensitivity was 0.73, the specificity was 0.98, the LR+ was 7.82,the LR-was 0.32, the DOR was 31.65, the AUC(± SE) was 0.9925(± 0.0132), and the Q* index was 0.9649(± 0.0363). For DCE-MRI, the sensitivity was 0.41, the specificity was 0.97, the LR+ was 5.34, the LR-was 0.71, the DOR was 8.76, the AUC(± SE) was 0.9922(± 0.2218), and the Q* index was 0.8935(± 0.3037).CONCLUSION This meta-analysis demonstrated a beneficial value of PW-MRI(DSC-MRI and DCE-MRI) in monitoring the response of recurrent gliomas to antiangiogenic therapy, with reasonable sensitivity, specificity, +LR, and-LR.

Cerebral Microbleeds Identified by Susceptibility-Weighted Imaging in Two Cases of Fabry Disease without Neurological Symptoms

Cerebrovascular disease is one of the fatal causes of Fabry disease (FD). Brain magnetic resonance imaging findings typically show lacunar infarcts in young patients with FD, but brain hemorrhages in FD are rarely reported. We report two cases of FD focusing on cerebral microbleeds (CMBs). Susceptibility-weighted imaging (SWI) and T2*-weighted imaging reveal several lobar and deep CMBs in two patients with no medical history of stroke symptoms, hypertension, and anticoagulant/antiplatelet treatment. SWI can detect a greater number of CMBs than T2*-weighted imaging. Thus, SWI is an excellent tool for identifying underlying CMBs in FD.

The Clinical Application Value of Susceptibility Weighted Imaging in the Central Nervous System

Susceptibility weighted imaging(SWI)is a relatively new magnetic resonance imaging(MRI)technique that uses the difference in tissue magnetic susceptibility to image,and has unique value compared to traditional magnetic resonance imaging.This article summarizes its application in the central nervous system and provides a reference for imaging diagnosis and clinical treatment.

A multiple-tissue-specific magnetic resonance imaging model for diagnosing Parkinson’s disease: a brain radiomics study

Brain radiomics can reflect the characteristics of brain pathophysiology.However,the value of T1-weighted images,quantitative susceptibility mapping,and R2*mapping in the diagnosis of Parkinson’s disease(PD)was underestimated in previous studies.In this prospective study to establish a model for PD diagnosis based on brain imaging information,we collected high-resolution T1-weighted images,R2*mapping,and quantitative susceptibility imaging data from 171 patients with PD and 179 healthy controls recruited from August 2014 to August 2019.According to the inclusion time,123 PD patients and 121 healthy controls were assigned to train the diagnostic model,while the remaining 106 subjects were assigned to the external validation dataset.We extracted 1408 radiomics features,and then used data-driven feature selection to identify informative features that were significant for discriminating patients with PD from normal controls on the training dataset.The informative features so identified were then used to construct a diagnostic model for PD.The constructed model contained 36 informative radiomics features,mainly representing abnormal subcortical iron distribution(especially in the substantia nigra),structural disorganization(e.g.,in the inferior temporal,paracentral,precuneus,insula,and precentral gyri),and texture misalignment in the subcortical nuclei(e.g.,caudate,globus pallidus,and thalamus).The predictive accuracy of the established model was 81.1±8.0%in the training dataset.On the external validation dataset,the established model showed predictive accuracy of 78.5±2.1%.In the tests of identifying early and drug-naïve PD patients from healthy controls,the accuracies of the model constructed on the same 36 informative features were 80.3±7.1%and 79.1±6.5%,respectively,while the accuracies were 80.4±6.3%and 82.9±5.8%for diagnosing middle-to-late PD and those receiving drug management,respectively.The accuracies for predicting tremor-dominant and non-tremor-dominant PD were 79.8±6.9%and 79.1±6.5%,respectively.In conclusion,the multiple-tissue-specific brain radiomics model constructed from magnetic resonance imaging has the ability to discriminate PD and exhibits the advantages for improving PD diagnosis.

In vivo tracking of human adipose-derived stem cells labeled with ferumoxytol in rats with middle cerebral artery occlusion by magnetic resonance imaging

Ferumoxytol, an iron replacement product, is a new type of superparamagnetic iron oxide ap- proved by the US Food and Drug Administration. Herein, we assessed the feasibility of tracking transplanted human adipose-derived stem cells labeled with ferumoxytol in middle cerebral artery occlusion-injured rats by 3.0 T MRI in vivo. 1 × 104 human adipose-derived stem cells labeled with ferumoxytol-heparin-protamine were transplanted into the brains of rats with middle cerebral artery occlusion. Neurologic impairment was scored at 1, 7, 14, and 28 days after transplantation. T2-weighted imaging and enhanced susceptibility-weighted angiography were used to observe transplanted cells. Results of imaging tests were compared with results of Prussian blue staining. The modified neurologic impairment scores were significantly lower in rats transplanted with cells at all time points except I day post-transplantation compared with rats without transplantation. Regions with hypointense signals on T2-weighted and enhanced susceptibility-weighted angiography images corresponded with areas stained by Prussian blue, suggesting the presence of superparamagnetic iron oxide particles within the engrafted cells. Enhanced susceptibility-weighted angiography image exhibited better sensitivity and contrast in tracing ferumoxytol-heparin-protamine-labeled human adipose-derived stem ceils compared with T2-weighted imaging in routine MRI.

Susceptibility-Weighted MRI in the Evaluation of Gynecologic Diseases

Introduction: Owing to the advanced development of MRI science, it causes obvious great changes of many diseases that affect the female genital system and affect their fertility. Hemorrhagic gynecological diseases especially endometriosis affect young females and cause cyclic pain, in addition to infertility. So early detection is essential for proper treatment. Susceptibility-weighted (SWI) as one of the most recent newly created MRI sequences is highly sensitive to detect products of hemorrhage within different gynecologic disorders with 94.7% sensitivity being more meticulous than conventional MRI sequences as T1 and T2. Aim of the Work: A comparison between T1 and T2 as conventional MRI sequences with susceptibility-weighted images (SWI) in many gynecologic disorders by the detection of the presence of internal products of hemorrhage at any stage. Subjects and Methods: 48 consecutive patients from Benha University clinics (age range, 17 - 60 years;mean age, 35.67 years). The patients included in the study were presenting with pelvic pain, irregular menses, Dyspareunia, and swelling. All with suspicious diagnosis of ovarian and extra-ovarian lesions. 38 patients out of the 48 patients were known to contain hemorrhagic disorder;all the patients underwent MRI routine pelvis protocol adding SWI sequence. Results: There was a greatly significant difference between SWI and conventional MRI sequences T1and T2 with sensitivity 94.7%, 57.9% and 33.3% respectively. Conclusion: SWI is a promising tool in the evaluation of hemorrhagic foci within different gynecological disorders. The great ability of detecting hemosiderin foci increases the value of SWI over conventional MRI or US.

Magnetic Resonance Imaging and DWI Features of Orbital Rhabdomyosarcoma

Purpose: To describe the magnetic resonance imaging(MRI)features of orbital rhabdomyosarcoma(RMS).Methods: Thirty-nine patients with histopathologically confirmed orbital RMS were retrospectively reviewed. All patients underwent orbital conventional MRI, including axial, sagittal,and coronal T1-weighted, T2-weighted, and postcontrast T1-weighted sequences. The location, shape, margin, and MRI signal of the 39 lesions were reviewed. DWI in 15 patients and susceptibility weighted imaging(SWI) in 2 patients were also analyzed.Results: Orbital MRI was available in 39 patients and revealed a soft tissue mass in the orbital region in all cases. Of the 39 patients, the primary tumor sites were limited to the orbital proper in 31 cases, while 28 cases had extraocular muscle invasion and 8 cases had extraorbital invasion. All lesions were unilateral. Thirty-three cases were well-defined soft tissue masses and 6 cases appeared as less well-defined softtissue masses. Thirty-four cases showed homogeneous isointense or slightly hypointense signals on T1-weighted imaging(T1WI) and hyperintense signal on T2-weighted imaging(T2WI) compared with extraocular muscles. Five cases had heterogeneous signals with focal areas of increased signal on T1WI or decreased signal on T2WI, including 1 case with hypointense signal on SWI. The mean apparent diffusion coefficient(ADC) value of the viable part of tumors was(0.925±0.09)×10-3mm2/ s. All cases showed moderate to marked enhancement after contrast administration.Conclusion: Several MRI features-including homogeneous isointense or slightly hypointense signal on T1WI and slightly hyperintense signal on T2WI, relative low ADC values, and moderate to marked enhancement, extraocular muscles invasion, and extraorbital extensionare helpful in the diagnosis of orbital RMS.

临床医用1.5T磁共振对AD模型大鼠的颅脑MR成像研究

目的使用临床医用1.5TMR成像仪对阿尔茨海默病(Alzheimer Disease,AD)大鼠模型的颅脑行MR成像研究。材料和方法随机选择健康雌性SD大鼠10只(7-8周),通过多影响因素建立SD大鼠的AD模型,然后使用临床医用1.5TMR成像仪对AD模型大鼠进行T1WI、T2WI、T2*WI、SWI成像。结果 AD模型大鼠大脑的颞顶叶皮质、腹侧海马下皮质区和海马区可以发现一些散在的类圆形的低信号区,并与脑实质Aβ免疫组化、Thioflavine S及铁染色阳性结果相重叠。结论在未有超高场小动物专用磁共振成像仪的情况下,临床医用磁共振对AD模型大鼠颅脑MR成像的研究是可行的。

1.5T磁共振磁敏感成像在脑出血性病变中的诊断价值

目的探究1.5T磁共振磁敏感成像(SWI)对脑出血性病变的诊断及预后评估价值。方法选取2018年1月至2019年6月150例脑出血患者,所有患者入院24 h内接受常规颅脑MRI检查(常规T_(1)WI、T_(2)WI、FLAIR序列)及SWI序列扫描,比较常规MRI与SWI扫描下出血灶及微出血灶检出率、出血面积、出血量,对比常规MRI与SWI扫描的图像特征、特殊病因检出情况,采用Pearson相关分析法评价SWI下出血面积、出血量与格拉斯哥昏迷评分(GCS)、格拉斯哥预后评分(GOS)相关性。结果SWI扫描下出血灶及微出血灶检出率均为100.00%,显著高于常规MIR 83.82%、30.56%(P<0.05),检测出血面积、出血量分别为(6.89±11.97)cm^(2)、(44.32±12.21)mL,高于常规MRI[(5.64±1.82)cm^(2)、(35.59±9.77)mL],差异具有统计学意义(P<0.05);SWI下出血灶成像较常规MRI更清楚、边界更清晰;SWI下特殊病因检出率14.67%(22/150),高于常规MRI[7.33%a(11/150),P<0.05];SWI下出血灶面积、总出血量与GCS评分、GOS评分均呈负相关(P<0.05)。结论相比常规MRI检查,SWI扫描等脑出血患者出血灶显示更为清楚,能提高出血灶检出率,且利于出血面积、出血量及病因评估,对患者预后评估及临床干预有指导意义。

Diffusion kurtosis imaging of microstructural changes in brain tissue affected by acute ischemic stroke in different locations

The location of an acute ischemic stroke is associated with its prognosis. The widely used Gaussian model-based parameter, apparent diffusion coefficient(ADC), cannot reveal microstructural changes in different locations or the degree of infarction. This prospective observational study was reviewed and approved by the Institutional Review Board of Xiamen Second Hospital, China(approval No. 2014002).Diffusion kurtosis imaging(DKI) was used to detect 199 lesions in 156 patients with acute ischemic stroke(61 males and 95 females), mean age 63.15 ± 12.34 years. A total of 199 lesions were located in the periventricular white matter(n = 52), corpus callosum(n = 14), cerebellum(n = 29), basal ganglia and thalamus(n = 21), brainstem(n = 21) and gray-white matter junctions(n = 62). Percentage changes of apparent diffusion coefficient(ΔADC) and DKI-derived indices(fractional anisotropy [ΔFA], mean diffusivity [ΔMD], axial diffusivity [ΔD_a], radial diffusivity ΔDr, mean kurtosis [ΔMK], axial kurtosis [ΔK_a], and radial kurtosis [ΔK_r]) of each lesion were computed relative to the normal contralateral region. The results showed that(1) there was no significant difference in ΔADC, ΔMD, ΔD_a or ΔD_r among almost all locations.(2) There was significant difference in ΔMK among almost all locations(except basal ganglia and thalamus vs. brain stem; basal ganglia and thalamus vs. gray-white matter junctions; and brainstem vs. gray-white matter junctions.(3) The degree of change in diffusional kurtosis in descending order was as follows: corpus callosum > periventricular white matter > brainstem > gray-white matter junctions > basal ganglia and thalamus > cerebellum. In conclusion, DKI could reveal the differences in microstructure changes among various locations affected by acute ischemic stroke, and performed better than diffusivity among all groups.

Magnetic resonance susceptibility weighted imaging in detecting intracranial calcification and hemorrhage

Background Computed tomography （CT） is better than routine magnetic resonance imaging （MRI） in detecting intracranial calcification. This study aimed to assess the value of MR susceptibility weighted imaging （SWI） in the detection and differentiation of intracranial calcification and hemorrhage. Methods Enrolled in this study were 35 patients including 13 cases of calcification demonstrated by CT and 22 cases of intracerebral hemorrhage. MR sequences used in all the subjects included axial T1WI, T2WI and SWI. The phase shift （PS） of calcification and hemorrhage on SWI was calculated and their signal features on corrected phase images were compared. The sensitivity of T1WI, T2WI and SWI in detecting intracranial calcification and hemorrhage was analyzed statistically. Results The detection rate of SWI for cranial calcification was 98.2%, significantly higher than that of T1WI and T2WI. It was not significantly different from that of CT （P 〉0.05）. There were 49 hemorrhagic lesions at different stages detected on SWI, 30 on T2WI and 18 on T1WI. The average PS of calcification and hemorrhage was ＋0.734±0.073 and -0.112±0.032 respectively （P 〈0.05）. The PS of calcification was positive and presented as a high signal or the mixed signal dominated by a high signal on the corrected phase images, whereas the PS of hemorrhage was negative and presented as a low signal or the mixed signal dominated by a low signal.Conclusions SWI can accurately demonstrate intracranial calcification, not dependant on CT. Being more sensitive than routine MRI in detecting micro-hemorrhage, SWI may play an important role in differentiating cerebral diseases associated with calcification or hemorrhage.

1.5T磁敏感加权成像在检测腔隙性脑梗塞中微出血的应用价值分析

目的 探究1.5T磁敏感加权成像（SWI）在诊断腔隙性脑梗塞中微出血（CMBs）应用价值。方法 回顾性分析2015年4月-2016年4月于本院医治的腔隙性脑梗塞CMBs患者63例为甲组,同期选取于我院检查的健康人群53例为乙组,两组均予SWI技术检查,观察两组CMBs阳性检出率及病灶信号特征。结果 甲组CMBs阳性检出率90.48%比乙组高16.98%（P〈0.05）;两组病灶信号特征对比差异无统计学意义（P〉0.05）。结论 SWI用于检查腔隙性脑梗塞CMBs具较高价值,可作为诊断的理想手段。

1.5T磁共振扩散加权成像在急性脊髓损伤诊断中的临床应用价值分析

研究1.5T磁共振扩散加权成像在急性脊髓损伤诊断中的临床应用价值。方法：收治急性脊髓损伤患者50例，分别对患者颈部病变部位以及周围2个脊椎距离的相对正常区域进行磁共振检测。结果：颈髓内常规MRI图像无异常信号26例，26例患者在相应的C5～6以及C5层面其ADC值的降低显著低于对照层面(P＜0.05)；MRI及DWI有异常信号患者24例，损伤部位较正常部位ADC值有明显减低(P＜0.05)。结论：1.5T磁共振扩散加权成像在急性脊髓损伤诊断中具有很高的临床应用价值。

1.5T MRI对肝硬化结节癌变的诊断与临床应用

目的探讨1.5TMRI对肝硬化结节癌变的诊断与临床应用价值。方法选取2018年8月—2020年8月阳春市人民医院确诊的肝硬化结节患者90例作为研究对象,使用西门子ESSENZA 1.5T MIR机对病灶进行扫描,分析不同性质结节的MRI平扫、增强扫描、DWI、SWI图像特征差异。结果查出再生结节(RN)21处,在T1WI与T2WI上呈现为等信号影,增强扫描可见与正常肝组织实质相似,DWI上呈等信号,SWI则呈现为低信号影。查出异型增生结节(DN)45处,T1WI上表现为高信号影,T2WI上为低信号或等信号影,增强扫描可见门静脉期轻度强化,DWI图像为高信号或等信号影,SWI为低信号影。查出小肝癌(sHCC)98处,T1WI呈低信号,T2WI呈高信号,增强扫描可见门静脉血供下降趋势明显,而动脉期血供则逐渐增加,DWI图像多呈高信号影,SWI图像则多呈低信号影。结论1.5T MRI扫描对肝硬化结节患者病灶癌变具有显著的诊断价值,尤其是SWI扫描,能够通过对不同性质结节内铁含量差异的评价,为肝硬化结节患者癌前病变和小肝癌的鉴别诊断提供依据。

1.5T磁共振磁敏感加权成像技术在脑部微出血病灶中的诊断价值

目的:探究1.5T磁共振磁敏感加权成像(susceptibility weighted imaging,SWI)技术在脑部微出血病灶中的诊断价值。方法:回顾性分析新疆生产建设兵团第十师北屯医院2022年4月—2023年4月收治的55例轻度创伤性颅脑损伤患者的病历资料,所有患者在术前均使用磁共振SWI技术、磁共振常规序列明确微出血病灶。比较不同检查序列对脑部微出血病灶的检出情况,分析脑部微出血灶分布及影像特征。结果:SWI序列检测结果显示,37例(67.27%)患者存在脑部微出血病灶,与Flair(14.55%)、T1WI(7.27%)、T2WI(10.91%)常规序列检查结果比较,差异有统计学意义(P<0.05)。经磁共振检查发现37例脑部微出血患者,共检出63个微出血病灶,分布在基底节区21个(33.33%)、白质13个(20.64%)、放射冠11个(17.46%)、丘脑10个(15.87%)、脑干8个(12.70%)。脑部微出血病灶直径为0.3~7.3mm,且脑部微出血病灶SWI序列信号表现为圆形低信号或者多发点状低信号阴影。结论:在脑出血症状的诊断过程中,利用磁共振磁敏感加权成像技术进行诊断有助于帮助临床医师明确轻度创伤性颅脑损伤患者脑部微出血病灶位置与数量,可为临床诊治提供参考。

1.5T SWI检测腔隙性脑梗死中微出血的应用价值

目的:研究分析1.5T磁敏感加权成像(SWI)在检测腔隙性脑梗死中微出血(CMBs)的应用价值。方法:分别选取2016年8月至2017年10月在新乡市第二人民医院接受检查的50例腔隙性脑梗死患者及50例健康体检者展开研究,对应分为观察组和对照组,对两组患者予以1.5T SWI检查,探讨其在腔隙性脑梗死中微出血的应用价值。结果:在不同序列显示微出血灶的比较上,SWI显著优于GRE–T2*WI,而GRE–T2*WI又显著优于T1WI、T2WI,差异具有统计学意义(P <0.05)。观察组SWI序列的微出血检出率比对照组更高,差异具有统计学意义(P <0.05)。结论:临床在检测腔隙性脑梗死微出血中采用1.5T SWI能够获得较高的检出率,能有效反应微出血严重程度、发生部位等情况,具有较高的诊断价值。

对比增强SWI对不同病理类型肺癌脑转移瘤的诊断价值

目的:探讨对比增强磁敏感加权成像(CE-SWI)与常规对比增强T 1WI成像(CE-T 1WI)对不同病理类型肺癌脑转移瘤的检出率差异,分析脑转移瘤内出现对比剂诱导相移(CIPS)与原发性肺癌病理类型间的关联性。方法:搜集经病理证实的79例原发性肺癌患者,其中腺癌组40例,鳞癌组18例,小细胞癌组21例,均行颅脑MR常规平扫、SWI、CE-T 1WI及CE-SWI检查,比较CE-SWI与CE-T 1WI检出的脑转移瘤数目及转移瘤内是否存在CIPS,转移灶经3个月后随访证实。结果:CE-T 1WI与CE-SWI对腺癌脑转移瘤的检出率差异有统计学意义(χ^(2)=5.05,P=0.025),对鳞癌(χ^(2)=0.00,P=1.000)与小细胞癌(χ^(2)=0.27,P=0.603)脑转移瘤的检出率差异无统计学意义。腺癌组、鳞癌组、小细胞癌组三组间CIPS阳性率差异有统计学意义(χ^(2)=11.13,P=0.004),其中鳞癌组与腺癌组(χ^(2)=11.08,P=0.001)、鳞癌组与小细胞癌组(χ^(2)=8.26,P=0.004)间差异有统计学意义,腺癌组与小细胞癌组间差异无统计学意义(χ^(2)=0.131,P=0.717)。结论:CE-SWI对肺腺癌脑转移瘤的检出较CE-T 1WI更有优势。肺腺癌、小细胞癌脑转移瘤的CIPS阳性率较鳞癌显著增高,CE-SWI可为肺癌脑转移瘤MRI检查常规序列的有利补充,为临床诊疗提供更多重要参考信息。

1.5T MR在儿童内耳畸形诊断中的应用分析

目的探讨1.5T MR在儿童内耳畸形诊断中的应用效果,为临床诊治提供有效指导。方法回顾性收集广州市妇女儿童医疗中心2018年10月—2019年9月就诊的100例内耳畸形患儿临床资料,参照确诊结果,分析1.5T MR对儿童内耳畸形诊断灵敏度、特异度、准确度及与疾病类型一致性。结果100例患儿200耳中,内耳畸形187耳,占93.50%;其中耳蜗畸形50耳,占26.74%;前庭畸形52耳,占27.81%;半规管畸形43耳,占22.99%;耳道发育异常21耳,占11.23%;蜗神经发育不良11耳,占5.88%;内淋巴管及内淋巴囊扩大10耳,占5.35%。参照临床确诊结果,1.5T MR对内耳畸形诊断灵敏度为97.86%,特异度为75.00%,准确度为97.50%;1.5T MR诊断与临床诊断内耳畸形类型具有极好的一致性(Kappa=0.973)。结论1.5T MR在儿童内耳畸形诊断中具有良好应用效果,可有效区分内耳畸形类型,为临床治疗提供有效指导,值得临床推广应用。