体素内不相干运动扩散加权成像（IVIM-DWI）定量研究育龄期女性正常子宫月经周期内微循环变化

目的:探讨体素内不相干运动扩散加权成像(IVIM-DWI)定量测量正常子宫微循环灌注随月经周期变化的价值.方法:10例育龄期健康女性志愿者于经期(第3天)、增生早期(第7天)、增生晚期(第12天)、分泌早期(第17天)及经前期(第27天)行盆腔MRI扫描.扫描序列包括T1WI、T2 WI和IVIM.测量子宫内膜、结合带及外肌层的真实扩散系数(D)、假性扩散系数(D*)和灌注分数(f).比较月经周期各时间点D、D*及f值的差异,统计方法采用随机区组设计方差分析.结果:不同时间点间两两比较,子宫的三层结构中仅内膜的f值在经前期与增生早期以及结合带的f值在经前期与经期、经前期与增生早期间的差异具有统计学意义(P值分别为0.015、0.037、0.038),其余各时间点间f、D和D*值的差异无统计学意义(P＞0.05);内膜的f值自增生早期至经前期呈现先上升后下降的变化趋势,且在增生晚期达峰值.子宫3层结构间两两比较,在经期、增生早期、分泌早期和经前期,内膜与结合带、结合带与外肌层间D值的差异具有统计学意义(P值分别为0.048、0.024、0.009和0.014;0.029、0.001、0.004和0.000),且D值的大小为结合带＜内膜＜外肌层;除经期外,其它4期时子宫内膜与外肌层、结合带与外肌层间f值的差异均有统计学意义(P＜0.05);除经期和增生晚期,其它3期时子宫内膜与外肌层、结合带与外肌层间D*值的差异亦具有统计学意义(P＜0.05).结论:IVIM-DWI是非侵入性评价正常子宫在月经周期中微循环变化情况的有效方法.     

3.0T MRI对绝经前女性正常子宫的ADC值研究

目的研究不同年龄段绝经前女性的正常子宫三层结构(肌层、结合带及内膜)在不同月经周期的表观扩散系数(apparent diffusionco efficient,ADC)的变化。资料与方法将67名健康女性分成三组(A组20～29岁,B组30～39岁,C组40～49岁),分别于增殖中期及分泌中期行2次MR检查,研究不同结构区、年龄段及生理周期对子宫ADC值的影响。结果子宫三层结构的ADC值在同一周期同一年龄组两两比较均有明显差异(肌层最高,内膜居中,结合带最低);B组内膜的ADC值在两期均高于A组和C组,而A组和C组内膜的ADC值在两期均无明显差异,其余结构区无明显年龄差异;各个年龄段子宫内膜的ADC值在增殖中期均低于分泌中期,而各年龄段肌层与结合带的ADC值在不同周期间差异不明显。结论不同结构区、年龄及周期会对子宫(尤其内膜)的ADC值产生影响,当利用ADC值精确分析子宫病变时应考虑这些因素,尤其有助于监测疗效及鉴别肿瘤复发。     

3.0TMRI 对青年女性正常子宫ADC 值周期性变化的研究

目的：研究青年女性正常子宫体各结构表观扩散系数（ADC ）值在不同月经周期的变化规律,并探讨其生理机制及临床意义。方法19例健康青年女性分别于围排卵期、分泌晚期及月经期接受3次子宫体扩散加权成像（DWI）（b＝0,1000 s／mm2）扫描,后分别测量子宫内膜、结合带及子宫肌层的ADC值并分析各结构ADC值的差异及其在不同月经周期的变化规律。结果特定月经周期不同子宫结构ADC值之间均有显著统计学差异（P＜0．05）,其中子宫肌层ADC值最高,子宫内膜居中,结合带最低;特定子宫结构在不同月经周期下ADC值存在显著统计学差异（F＝55．674,P＜0．05）;月经周期与子宫结构之间存在交互效应（F＝12．501,P＜0．05）。结论不同结构区及月经周期会对子宫ADC值产生影响,采用ADC值分析子宫病变时,应考虑到子宫不同结构区、不同月经周期对子宫ADC值的影响。     

磁共振弥散加权成像在子宫内膜癌的初步研究

目的 探讨磁共振弥散加权成像(diffusion weighted imaging,DWI)在子宫内膜癌中的诊断价值.方法 正常妇女子宫45例,子宫内膜癌(endometrial carcinoma,EC) 35例,均进行横断面、矢状面常规MRI扫描及不同b值下(b=500、800、1 000 s/mm2)横断面及矢状位扩散加权成像,分别测量正常子宫体3层结构和子宫内膜癌病灶的信噪比(signal to noise ratio,SNR)及表观扩散系数(appareent diffusion coefficient,ADC)值,膀胱的信号强度比(signal intensity ratio,SIR),并进行比较.结果 正常子宫三层结构的T2WI图像信号强度有差异,内膜层信号度最高,结合带最低;在DWI图像上内膜信号强度分别高于结合带和外带,结合带和外带的差异肉眼不易分辨.正常对照组子宫同一层组织在不同b值下所得ADC值之间差异无统计学意义(P>0.05);宫体内膜与结合带ADC值之间差异无统计学意义(P>0.05),而宫体内膜与肌层、结合带与肌层ADC值之间差异有统计学意义(P<0.01).扩散图像中肿瘤SNR随着b值增加而逐渐下降.b=500 s/mm2时,正常子宫内膜与子宫内膜癌ADC值之间的差异无统计学意义(P>0.05); b=800、1 000 mm2/s时,正常子宫内膜ADC分别为(1.541±0.148)×10-3mm2/s和(1.530±0.119)×10-3mm2/s,均高于EC病灶的(0.984±0.162) ×10-3mm2/s和(0.775±0.153)×10-3 mm2/s,两者之间的差异有统计学意义(F=32.919,P<0.01).但高分化子宫内膜样腺癌和中分化子宫内膜样腺癌的ADC值之间在不同b值间无统计学意义(P＞0.1).结论 b=800 s/mm2和1 000 s/mm2是子宫内膜癌成像的较佳b值.ADC值对鉴别正常子宫体内膜与子宫内膜癌有一定的参考价值,但对于鉴别不同分化程度的子宫内膜样腺癌仍有一定困难.     

轻度认知障碍患者海马的磁共振扩散峰度成像研究

目的 应用磁共振扩散峰度成像(DKI)研究轻度认知功能障碍(MCI)患者及正常老年人海马的差异.方法 搜集23例MCI患者为病例组(MCI组),23名健康志愿者为正常对照组(HC组),分别测量双侧海马的平均峰度(MK)值、轴向峰度(Ka)值、径向峰度(Kr)值、各向异性分数(FA)值、平均扩散(MD)值、轴向扩散(Da)以及径向扩散(Dr)值,使用两独立样本t检验对两组间所测DKI各参数进行分析;使用受试者工作特征曲线(ROC)曲线下面积(AUC)评价上述各参数值诊断MCI的能力;使用Pearson相关性分析对上述海马的DKI各参数值与MMSE评分的相关性进行分析.结果 与HC组相比,MCI组双侧海马的MK值、Kr值、FA值、Da值、Dr值减低,差异具有统计学意义(P＜0.05),双侧海马的MD值增加,差异具有统计学意义(P＜0.05),双侧海马的Ka值比较差异无统计学意义(P＞0.05);ROC曲线显示,左侧海马MD值的AUC最大,为0.765;Pearson相关性分析结果,双侧海马的MK值、Kr值、FA值、MD值、Da值、Dr值与简易精神状态检查量表(MMSE)评分均具有相关性(P＜0.05),海马的Ka值与MMSE评分无相关性(P＞0.05).结论 DKI技术能够敏感地探测到MCI患者海马的变化,为MCI患者和正常对照者的鉴别提供有效的影像学方法.     

扩散峰度成像和3D动脉自旋标记成像对脑胶质瘤术前分级的诊断价值及相关性研究

目的：探讨扩散峰度成像（DKI）和3D动脉自旋标记成像（3D ASL）对脑胶质瘤术前分级的诊断价值及相关性。方法：收集36例经病理证实的脑胶质瘤患者,分别行常规MRI平扫、DKI、3D ASL及增强扫描,经后处理得到DKI、3D ASL相关参量图,选择肿瘤实性部分和对侧正常脑白质,分别测量平均扩散峰度（MK）、径向扩散峰度（Kr）、轴向扩散峰度（Ka）和部分各向异性（FA）、平均扩散系数（MD）、脑血流量（CBF）,并计算各相对参数值rMK、rKr、rKa、rFA、rMD和rCBF。采用两样本t检验,比较分析不同级别脑胶质瘤的各参数值及相对参数值。采用Spearman相关分析rMK值、rCBF值及病理级别三者间的相关性。绘制rMK值与rCBF值诊断高级别脑胶质瘤的ROC曲线,计算AUC,寻找最佳诊断界值,两者AUC比较行Z检验。结果 ：经检验分析,MK、Kr、Ka值在不同病理级别胶质瘤中差异均有统计学意义（均P<0.05）,FA、MD值在不同病理级别胶质瘤中差异无统计学意义（均P> 0.05）。不同病理级别胶质瘤的rMK、rKr、rKa、rFA、rMD值及rCBF值差异均有...     

磁共振灌注加权成像对不孕症患者子宫内膜容受性评估价值的研究

目的 探讨子宫内膜厚度、内膜下灌注参数与子宫内膜容受性的关系和MR灌注加权成像(PWI)评价子宫内膜容受性的价值.方法 对22例不孕症(不孕组)及15名健康女性(对照组)分泌中期行MRI平扫及PWI,分别测量内膜厚度、内膜及内膜下灌注参数正性增强积分(PEI)、达峰时间(TrP)、平均强化时间(MTE)、最大增强线性斜率(MSI),比较两组各血流灌注参数间的差异.两组间内膜厚度及各灌注参数的比较采用两样本均数的t检验,内膜厚度与PEI间相关性分析采用Pearson法.结果 不孕组与对照组内膜厚度之间差异具有显著统计学意义(t=6.54,P＜0.01).内膜两组灌注参数PEI、MSI、MTE值差异具有统计学意义(=2.45、2.12、2.23,P＜0.05),TTP值差异无统计学意义(t=1.25,P＞0.05);内膜下两组各灌注参数值比较差异均无统计学意义(t=1.42、1.00、2.03、1.75,P＞0.05).子宫内膜厚度与PEI值进行回归分析,两者之间呈明显正相关(r=0.763,P＜0.01).结论 MR-PWI能够定量反映子宫内膜及内膜下的血流灌注状态,且内膜厚度与血容量之间存在一定相关性,对不孕患者子宫内膜容受性的评估有一定价值.     

扩散峰度成像预估宫颈鳞癌病理分级的价值

目的：探讨扩散峰度成像(DKI)定量参数预估宫颈鳞状细胞癌(CSCC)病理分级的价值。方法回顾性分析45例CSCC患者的DKI图像,按照病理结果分为低分化组22例,高中分化组23例。由2位观察者分别测量2组病灶实质区DKI各参数值,包括平均扩散峰度值(MK)、平行扩散峰度值(Ka)、垂直扩散峰度值(Kr)、峰度各向异性分数(FAk)、平均扩散系数值(MD)、平行扩散系数值(Da)、垂直扩散系数值(Dr)及各向异性分数(FA)。采用组内相关系数(ICC)对2位观察者各参数测量结果一致性进行检验;采用两独立样本t检验比较2组各参数值;采用受试者工作特征曲线(ROC)评估各参数预估低分化 CSCC的效能,并找出相应界值。结果2位观察者测得2组病灶各参数值的一致性良好(ICC>0.75)。低分化组MK、Ka及Kr值大于高中分化组(P<0.05),低分化组 MD、Da及Dr值小于高中分化组(P<0.05),2组 FAk及 FA值间无差异(P>0.05)。MK、Ka、Kr、MD、Da、Dr值预估低分化CSCC的曲线下面积(AUC)分别为0.914、0.831、0.865、0.850、0.778、0.865,MK≥0.973、Ka≥1.075、Kr≥0.823、MD≤0.974μm2/ms、Da≤1.185μm2/ms、Dr≤0.762μm2/ms为预估低分化CSCC的界值。结论 DKI能够有效地预估CSCC的病理分级,有着很好的临床应用前景。     

超高b值扩散峰度成像对前列腺癌的诊断及肿瘤分级评估价值

【摘要】目的：探讨超高b值扩散峰度成像（DKI）对前列腺癌（PCa）的诊断及肿瘤分级评估价值。方法：回顾性分析经病理证实的63例PCa及39例前列腺增生（BPH）患者的术前DWI图像。计算癌灶及良性病灶的表观扩散系数(ADC3000)、DKI扩散系数（D7b）及峰度系数（K）。依据术后病理结果,将63例PCa患者分为低危组（Gleason评分=3+3、3+4）、中危组（Gleason评分=4+3、4+4）及高危组（Gleason评分≥9）,比较低、中、高危组前列腺癌组织的D7b、K及ADC3000值,分析DKI预测PCa组织Gleason评分的能力。结果：外周带：39例癌灶的平均K值较39例良性病灶高,ADC3000及D7b值较良性病灶低,差异均有统计学意义（P值均<0.01）。 DKI(D+K)及ADC3000 诊断外周带PCa的曲线下面积（AUC）分别为0.968及0.971。移行带：24例癌灶的平均K值较39例BPH高,ADC3000及D7b值较BPH低,差异均有统计学意义（P值均<0.01）。DKI(D+K)及ADC3000 诊断移行带PCa的AUC分别为0.963及0.955。低危组PCa的平均D、ADC3000值与中、高危组差异均有统计学意义（P<0.001）,低危组PCa的平均K值仅与高危组差异有统计学意义（P<0.001）。结论：b值最高为4000s/mm2时,DKI模型可用于PCa的鉴别诊断及肿瘤分级评估;相比ADC3000,DKI模型尚不能提供更多的临床诊断信息。     

扩散峰度成像对高级别胶质瘤及单发脑转移瘤的鉴别诊断价值

【摘要】目的：探讨磁共振扩散峰度成像（DKI）的多参数值对高级别胶质瘤（HGG）和单发脑转移瘤（SBM）的鉴别诊断价值。方法：搜集经手术病理或临床随访证实的19例HGG患者和14例SBM患者的病例资料,术前均行常规MRI扫描、DKI扫描及增强扫描。选取兴趣区（ROI）测定其DKI参数,并进行矫正处理得到各向异性分数（FA）、平均扩散（MD）及平均峰度（MK）值。应用独立样本t检验对两组间各参数值进行统计学分析,绘制ROC曲线计算敏感度、特异度及曲线下面积（AUC）。结果：两组肿瘤实质区DKI各参数值差异无统计学意义（P＞0.05）;而瘤周区的FA值、MD值及MK值在两组间的差异有统计学意义（P＜0.05）。ROC曲线分析显示,瘤周区的MK值鉴别两种肿瘤的敏感度和特异度较FA值和MD值高,曲线下面积最大。结论：瘤周区的FA值、MD值及MK值对HGG和SBM有良好的鉴别诊断价值,且瘤周区MK值诊断效能最高。     

MR imaging of the uterus and cervix in healthy women: Determination of normal values

The purpose of this study was to establish normal values for the volume of the uterus and cervix in MRI based on age and the menstrual cycle phase. We performed MRI of the pelvis in 100 healthy women. For the uterus, they were further divided into two groups: one with myomas and/or adenomyosis and one without either. The volume of the uterus and cervix and thickness of the uterine wall layers were analysed by age and the menstrual cycle phase. The mean volume of the uterus in both groups and the cervix significantly increased with age to reach its peak at 41–50 years, and then dropped. Likewise, the thickness of the endometrium and the junctional zone, but not the myometrium, significantly increased until 41–50 years, and then decreased. When we compared the volume of the uterus and cervix and the thickness of the uterine wall layers between the two phases of the menstrual cycle, we found no significant differences. The volume of the uterus and cervix and the thickness of the endometrium and junctional zone differ significantly with age, but not between the two phases of the menstrual cycle. Knowledge of MRI-related normal values can be expected to aid the early identification of uterine pathologies.     

Physiological changes of the human uterine myometrium during menstrual cycle: preliminary evaluation using BOLD MR imaging

PURPOSE: To investigate the T2* values within the junctional zone and outer uterine myometrium and their changes during the menstrual cycle, and thus to evaluate their physiologic changes on blood oxygenation level-dependent (BOLD) magnetic resonance (MR) imaging. MATERIALS AND METHODS: Single-shot echo-planar imaging (EPI) was used to acquire T2*-weighted images (TR/TE = 1000 msec/23-150 msec) from 15 healthy females with a 1.5-T magnet. T2* values of both junctional zone and outer uterine myometrium were measured within a single breathhold and during three menstrual cycle phases (menstrual, periovulatory, and luteal phase). Signal intensities of uterine myometrium on T2-weighted images were also evaluated. RESULTS: T2* could successfully be calculated in 13 subjects. T2* values for the junctional zone were significantly lower than those of the outer myometrium at every phase(P < 0.001), and T2* values of both junctional zone (P < 0.05) and outer (P < 0.01). Myometrium in the menstrual phase was significantly lower than those in the other phases. On T2-weighted images, the signal intensity of the junctional zone was significantly lower than outer myometrium in every phase (P < 0.01), but there was no significant difference among menstrual cycle phases in both layers (P > 0.05). CONCLUSION: This preliminary study suggested that menstrual cycle changes of the uterine myometrium were shown by BOLD imaging. BOLD MR imaging may be an potential modality to investigate physiologic changes of the uterine myometrium during the menstrual cycle.     

绝经前女性正常宫颈组织的表观弥散系数值研究

目的探讨不同年龄段绝经前女性正常宫颈组织在不同生理周期的表观弥散系数值（apparent diffusion coef ficient,,ADC）变化。方法将82名健康女性按年龄段分成3组（A组27例,20～29岁;B组28例,30～39岁;C组27例,40～49岁）,采用3．0TMRl分别于增殖中期及分泌中期行2次盆腔MR检查,研究不同结构区、年龄段及生理周期的宫颈ADC值的变化。结果子宫3层结构的ADC值两两比较差异均有统计学意义（肌层最高,黏膜层居中,结合带最低）,宫颈黏膜层及结合带的ADC值在分泌中期均低于增殖中期,而肌层的ADC值在不同周期问差异不明显,宫颈每层结构在同一周期的各年龄组之间无明显差异,宫颈粘膜层在增殖中期的ADC值更为稳定。结论不同结构区及生理周期会对正常宫颈组织的ADC值产生影响,当利用ADC值探测早期宫颈癌、监测疗效及鉴别肿瘤早期复发时应考虑这些因素,绝经前女性应在增殖期行盆腔MR扫描。     

Apparent diffusion coefficient values of the normal uterus: Interindividual variations during menstrual cycle

Objectives

To assess the apparent diffusion coefficient (ADC) changes of the normal uterine zones among reproductive women during the menstrual cycle.

Methods

The study included 101 women of reproductive age, each with regular cycle and normal endometrium/myometrium, as proved on histopathology or MR imaging examination. Diffusion-weighted (DW) imaging was performed along the axial plane, using a single shot, multi-slice spin-echo planar diffusion pulse sequence and b-values of 0 and 800 s/mm². The mean and standard deviation of the ADC values of normal endometrium/myometrium were calculated for menstrual, proliferative and secretory phase. Analysis of variance followed by the least significant difference test was used for statistical analysis.

Results

The ADC values of the endometrium were different in the three phases of the menstrual cycle (menstrual phase: 1.25 ± 0.27; proliferative phase: 1.39 ± 0.20; secretory phase: 1.50 ± 0.18) (F: 9.64, p: 0.00). Statistical significant difference was observed among all groups (p < 0.05). The ADC values of the normal myometrium were different in the three phases of the menstrual cycle (menstrual phase: 1.91 ± 0.35; proliferative phase: 1.72 ± 0.27; secretory phase: 1.87 ± 0.28) (F: 3.60, p: 0.03). Statistical significant difference was observed between menstrual and proliferative phase and between proliferative and secretory phase (p < 0.05). No significant difference was noted between menstrual and secretory phase (p > 0.05).

Conclusions

A wide variation of ADC values of normal endometrium and myometrium is observed during different phases of the menstrual cycle.     

Changes in myometrial and junctional zone thickness and signal intensity: demonstration with kinematic T2-weighted MR imaging

PURPOSE: To demonstrate uterine contractions by evaluating changes during time in the thickness of the myometrium and junctional zone and in signal intensity of the uterus with T2-weighted fast magnetic resonance (MR) images in a kinematic fashion. MATERIALS AND METHODS: Sagittal MR imaging was performed with T2-weighted fast spin-echo (FSE) and multiphase-multisection single-shot FSE (SSFSE) in 60 premenopausal patients during free breathing. SSFSE MR images were evaluated with cine display. The pattern of uterine contractions and changes in signal intensities of the uterine structures were evaluated. Thickness of both myometrium and junctional zone, and their signal intensities, were measured during 15 phases of SSFSE and FSE MR imaging. RESULTS: Slow-massive (mean, 55%), middle-cycle (mean, 80%), and fine (mean, 93%) contractions were observed. Shape of junctional zones dynamically changed during time, showing focal (mean, 58%) and diffuse (mean, 82%) thickening and wavelike motions (mean, 88%). Ratio of thickness of the myometrium to junctional zone with FSE MR imaging was not significantly different from the mean ratio during 15 phases of SSFSE MR imaging, although maximum percentage of change of the ratio during 15 phases was 42.5%-56.8%. The signal intensities of the myometrium (97%) and junctional zone (75%) changed during time. CONCLUSION: Kinematic T2-weighted SSFSE MR images demonstrate uterine contractions related to dynamic changes in thickness and signal intensities of the myometrium and junctional zone, and these findings might affect the diagnosis of uterine disease.     

Oral contraceptives and uterine peristalsis: evaluation with MRI

PURPOSE: To evaluate the effects of oral contraceptives (OCs) on uterine contractility using cine MRI, and correlate the kinematic findings with the static findings. MATERIALS AND METHODS: Healthy female volunteers of reproductive age (23 taking OCs, and 15 not) were evaluated at mid-cycle. MR images were obtained with a 1.5T magnet, with 60 serial images taken every three seconds by half-Fourier acquisition single-shot turbo spin echo (HASTE) to be displayed in cine mode. Assessments were based on the 1) detectability of uterine peristalsis in cine mode, 2) peristaltic frequency and direction, 3) thickness of the endometrium, myometrium, and junctional zone (JZ) on T2-weighted images (T2WIs), and 4) intensity of the myometrium and cervical mucus on T2WIs and T1-weighted images (T1WIs), respectively. RESULTS: Uterine peristalsis was markedly decreased in the OC users. The endometrium and JZ were significantly thinner, and the myometrium was thicker in the OC users compared to controls. The signal intensity of the myometrium and cervical mucus was significantly higher in the OC users than in controls. CONCLUSION: OCs markedly suppressed uterine peristalsis at mid-cycle, and the uterus displayed a globular configuration with a thin JZ that may be related to decreased uterine peristalsis in OC users.     

Changes in apparent diffusion coefficients in the normal uterus during different phases of the menstrual cycle

This study investigated the apparent diffusion coefficients (ADCs) of the uterine zonal structures (myometrium, endometrium and junctional zone) among reproductive women, and their changes during the menstrual cycle. Magnetic resonance (MR) images of seven healthy females (aged 24–31 years) were obtained during the periovulatory, luteal and menstrual phases. Diffusion-weighted imaging (DWI) was performed with a single-shot echo-planar imaging (EPI) sequence in the midsagittal plane of the uterus using three b-values (b = 0, 500 or 1000 s mm⁻²). The ADC values of the three uterine zonal structures were measured on an ADC map by placing two regions of interest (ROI) on the corresponding zonal structures. The average changes of ADC values (intra-individual ADC value variation) over three menstrual phases were 0.41 × 10⁻³ mm² s⁻¹ (range, 0.08–0.91) for myometrium, 0.55 × 10⁻³ mm² s⁻¹ (0.35–0.84) for endometrium, and 0.40 × 10⁻³ mm² s⁻¹ (0.18–0.59) for the junctional zone. The ADC values for myometrium and endometrium were lower in the menstrual phase, although there was some overlap of individual values. Interindividual variation in ADC value for a given zone or phase ranged from 0.48 × 10⁻³ mm² s⁻¹ to 0.85 × 10⁻³ mm² s⁻¹. Intermeasurement variation between the two ROIs ranged from 0 to 0.48 × 10⁻³ mm² s⁻¹ per measurement. The magnitude of these variations was comparable to reported differences between malignant and non-malignant tissues. These preliminary results, from a small number of subjects, suggest that the menstrual cycle and individual variation in pre-menopausal women should be considered when interpreting the ADC values of uterine structures.Diffusion-weighted imaging (DW) is an emerging functional imaging technique that is based on the diffusion of water molecules [1]. DWI can measure the apparent diffusion coefficient (ADC) of the water in tissue, which reflects its cell density, cellular oedema and microcirculation [1, 2]. Malignant tissue tends to have low ADC values, and so ADCs are increasingly used as a quantitative parameter to distinguish malignant tissue from non-malignant tissue [3–5]. Recent studies in gynaecological imaging have reported ADC values that were lower than normal in uterine cervical cancer, endometrial cancer and leiomyosarcoma [6–8].In pre-menopausal women, T₂ weighted images of the uterus, a three-layer zonal structure, change during the menstrual cycle [9–11]. When the variation in the appearance of the uterus on T₂ weighted images and the underlying physiological changes are considered, it seems possible that there might be variation of ADCs in the normal uterus during the menstrual cycle, which could affect the baseline ADC values used in the assessment of uterine abnormalities. Thus, the purpose of this study was to investigate the ADC values of each zonal structure in the uterus among reproductive women, and their variation in three different phases of the menstrual cycle.     

3-T diffusion tensor imaging (DTI) of normal uterus in young and middle-aged females during the menstrual cycle: evaluation of the cyclic changes of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values

Objective:

To evaluate cyclic changes of fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values of normal uterus in different age groups during the menstrual cycle, and the correlation with serum female hormone levels.

Methods:

29 normal volunteers accepted diffusion tensor imaging of the uterus on menstrual phase (MP), follicular phase (FP), ovulatory phase (OP) and luteal phase. FA and ADC values of different uterine layers on midsagittal images were measured. Differences between two age groups during the menstrual cycle were evaluated using liner mixed models and one-way analysis of variance. Pearson correlation analysis compared variation of FA and ADC values with serum female hormone levels measured in MP.

Results:

During menstrual cycle, endometrial FA values declined, whereas ADC values increased with significant differences (p < 0.05). Serum oestradiol (E) levels correlated moderately with variations of FA values between MP-FP (p = 0.045; r = 0.389) and MP-OP (p = 0.008; r = 0.511). FA and ADC values of junctional zones showed no significant difference (p > 0.05) as well as FA values of myometrium (p = 0.0961), while ADC values of myometrium showed significant increase from menstrual phase to luteal phase (p < 0.05). FA and ADC values of uterine three zonal structures showed significant differences (p < 0.05) at each phase during the menstrual cycle. No significant difference of FA and ADC values was found between age groups (p > 0.05).

Conclusion:

Dynamic changes of uterine FA and ADC values were observed during menstrual cycle. Variation of FA values between MP-FP, MP-OP correlated moderately with serum E levels.

Advances in knowledge:

No publications on the relationship between FA and ADC values and the female hormone levels were found; our study prospectively investigated the cyclic changes of FA and ADC values of the normal uterus and the correlation with the basic serum female hormone levels in MP.Diffusion tensor imaging (DTI) is a well-established technique, which has been widely used in variable neurological diseases^1–4 and other parts of the body, such as the musculoskeletal system,^5,6 prostate^7,8 and kidney.^9,10In recent years, limited publications of its application in the female pelvis have been emerging. Current published studies include ex vivo and in vivo studies.^11–16 In 2006, three-dimensional fibre architecture of the normal human uterus based on DTI has been ex vivo evaluated in five samples by Weiss et al.¹¹ Toba et al¹² ex vivo study showed that DTI might be a useful tool for the diagnosis of myometrial invasion of uterine endometrial cancer. However, fractional anisotropy (FA) value of a normal uterus has not been thoroughly investigated yet. What is more there is no known publication, to the best of our knowledge, found on the relationship between FA value and female menstrual cycle. It would be ambiguous to use this MR parameter to evaluate malignancy situations without knowing the possible differences in various uterine structures, including endometrium, myometrium and junctional zone. In 2012, Fiocchi et al¹³ investigated the feasibility of depicting fibre architecture of the human uterus in vivo using 3-T MR-DTI based on 30 volunteers in different menstrual phases (MPs). In 2013, Fujimoto et al¹⁴ compared the DTI parameters in the different uterine layers of nine subjects in vivo, but limited their study group to the luteal phase (LP) only. A more comprehensive study based on 11 normal young females was reported by Kido et al;¹⁵ however, only apparent diffusion coefficient (ADC) value changes were evaluated during three phases of menstrual cycle. To the best of our knowledge, there are no published data focused on the cyclic changes of FA value in a normal uterus during four phases of menstrual cycle with a larger study cohort. Moreover, as it has been learned from MRI studies, anatomical and physiological characteristics of uterine structures, such as the endometrium and junctional zone, are heavily related to female hormone levels.^17–22 Nevertheless, no publications on the relationships between FA or ADC values and the hormone level were found.So, the aim of our study was to prospectively investigate the cyclic changes of FA and ADC values of the normal uterus in a larger population divided into different age groups during the four phases of the menstrual cycle, and the correlation with the basic serum hormone levels in MP.     

MR扩散加权成像对宫腔良恶性病变的鉴别诊断价值

目的:初步探讨DWI检查时表观扩散系数(ADC)值对局限于宫腔的子宫内膜癌与常见宫腔良性病变的鉴别诊断价值.方法:对32例经手术病理证实为局限于宫腔的子宫内膜癌和19例经分段诊刮病理检查证实为宫腔的良性病变(内膜增生l2例、内膜息肉7例)的患者行常规MRI和DWI检查(b=1000s/mm2),经后处理获得ADC图,测...