胎儿功能性磁共振成像研究
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摘要
第一部分胎儿脑单体素氢质子波谱成像的可行性研究
目的结合磁共振动态成像探讨胎儿脑单体素磁共振波谱成像的可行性。材料和方法50例20—40孕周的胎儿按羊水量的多少分为三组(羊水量多组6例、正常羊水量组21例和羊水量少组23例)，磁共振电影动态成像采用SSFSE矢状面观察胎儿头部运动，磁共振波谱成像在胎儿三个正交平面定位基础上使用单体素点分辨波谱(PRESS)序列行单体素磁共振波谱采集(TE=144ms)，MRS采集使用呼吸触发技术。结果羊水量多组、正常羊水量组和羊水量少组的羊水指数分别为(8.0±0.7)cm、正常羊水量组和羊水量过少组的羊水指数分别为(5.7±1.4)cm和(3.8±1.4)cm，其差异有统计学意义(F=17.95，P＜0.001)，羊水过多组胎儿运动频繁，MR电影成像可以观察胎儿身体多部位的翻转、伸展和转头，磁共振波谱采集分辨力较低，代谢物在谱线上成锯齿状分裂的峰，波谱成功率为0(0／6)，羊水量正常组胎儿头部运动减少，磁共振波谱采集分辨力较低，代谢物在谱线上可以分辨，但是有明显的噪声，波谱成功率为42.58％(9／21)，羊水过少组胎头活动明显受限，磁共振波谱采集成功率高，代谢物在谱线上分辨率高．波谱成功率为95.65％(22／23)，正常羊水量组和羊水量少组成功率差异有显著性意义(X~2=4.21，P＜0.05)。结论胎儿脑氢质子波谱成像是可行的，在胎儿正常脑发育和疾病的诊断方面有重要的价值。
第二部分正常胎儿脑发育的磁共振波谱成像研究
目的探讨正常胎儿脑发育代谢物水平的变化。方法选取35例符合纳入标准的孕妇，其中中期妊娠12例，晚期妊娠23例，孕周20周～40周，平均孕周34.6周。超声检查后1-2天内使用单次激发快速自旋回波序列(SSFSE)行胎儿颅脑常规MR扫描，扫描平面包括胎儿脑轴面、冠状面和矢状面。在胎儿脑三个正交平面定位的基础上以基底节和半卵圆中心为兴趣区(VOI)分别使用呼吸触发技术，采用定点分辨波谱序列(PRESS)行单体素~1H MRS扫描，(TE分别为144ms和35ms)。MRS测量值由机器自动给出，所测定的代谢产物包括N-乙酰基天门冬氨酸(NAA)、胆碱复合物(Cho)、肌酸复合物(Cr)、肌醇(mI)、谷氨酸及谷氨酰胺(Glx)等，其他参数包括均方根噪声(RMS noise)和肌酸信号噪声比(Cr SNR)。选取与研究组各孕周段匹配的16例正常胎儿作对照。结果正常胎儿的头围，双顶径线、腹围、股骨长与对照组差异无统计学意义，脑部MRI和产后检查未发现异常，TE=144ms时，胎儿脑MRS可以检测出三个主要波峰，分别为Cho峰，位于3.2ppm，Cr峰，位于3.0ppm，NAA峰，位于2.02ppm。Cho峰为第一高峰，孕34周前，Cr峰为第二高峰，孕34周后，NAA峰为第二高峰，和出生后新生儿波谱类似，NAA峰在孕22周已经可以辨别，乳酸峰不能检测出或较低平，MI峰也可检测出，位于3.56ppm；TE=35ms，可以检测到Cho峰、Cr峰、MI峰、NAA峰和谷氨酸及谷氨酰胺峰(Glx)。随着孕周的增加，TE=144时，NAA／S增加(P=0.007，r~2=0.20)，Cho／S减小(P=0.005，r~2=0.22)，Cr／S随孕周变化不明显(P=0.96，r~2=0.001)．TE=35ms时，NAA／S增加(P=0.05，r~2=0.21)，Cho／S减小(P=0.014，r~2=0.17)，MI峰减小(P=0.045，r~2=0.12)，Cr／S随孕周变化不明显(P=0.2，r~2=0.049)。
第三部分正常胎儿脑发育的MRI和DTI研究
目的联合应用单次激发自旋回波序列和扩散张量成像观察正常胎儿脑发育表现。方法应用SSFSE序列和扩散张量成像检查17例20～39孕周的宫内正常胎儿大脑。根据胎龄评估脑回的成熟度、灰白质的分层情况、于ADC图和FA图测量不同部位脑组织平均扩散度和部分各向异性值，并对其进行统计分析。结果(1)胎儿20～23周时，脑结构形态基本形成，此孕周段可见大脑呈典型的5层结构，24～27孕周的胎儿呈典型的3层结构。27孕周后仅存留2层结构。(2)20周左右皮层光滑、外侧裂可见，随着胎龄的增加，皮层迂曲、内凹、脑回逐渐形成，随之脑沟也形成加深，30周左右脑回、脑沟比较明显。(3)额叶、枕叶脑白质和基底节ADC平均值分别是1.83±0.3μm~2／ms，1.75±0.1μm~2／ms和1.65±0.1μm~2／ms，脑脊液的平均ADC值是2.9±0.6μm~2／ms。基底节和额叶、枕叶脑白质平均ADC差异有统计学意义。额叶、枕叶和基底节平均ADC值随年龄增加而降低，与年龄呈线性负相关。(4)孕20周可以追踪到感觉运动纤维，位于脑室旁，定位于中间带区，随着孕周增加，双侧内囊后肢的感觉运动纤维可以清楚显示，呈头尾方向。孕20周以后可以追踪到胼胝体膝部和压部白质纤维，内囊后肢的FA值随孕周增加而增大。结论联合SSFSE序列和DTI成像可以准确全面评价胎儿大脑实质随着孕龄发育成熟过程中的变化规律。
第四部分胎儿三维磁共振成像研究
目的探讨三维磁共振成像在显示胎儿正常和异常结构方面的临床应用价值。方法50例超声诊断或怀疑胎儿先天畸形的孕妇行胎儿MRI，年龄21～32岁，平均25.4岁，胎龄20～38周，平均28.6周。MR成像采用单次激发快速自旋回波序列(SSFSE)，在孕妇腹部三平面定位基础上常规行胎儿颅脑和胸腹部轴面，冠状面和矢状面扫描，41例使用三维快速成像稳态进动序列(3D—FIESTA)行胎儿三维成像。9例使用三维扰相梯度回波序列(3D-FSPGR)序列行胎儿结肠三维成像，图像传输到工作站进行三维图像后处理。MRI检查于超声检查后1～2天进行，MRI检查后对胎儿进行尸检和随访观察。二维及三维超声和MR图像分别由两位超声科医师和两位放射科医师采用双盲法进行分析。结果经过尸检和随访发现胎儿畸形58例，其中单发畸形为44例，4例为2处畸形，2例为3处畸形，(其中无脑畸形8例，脑膜脑膨出3例，小头畸形1例，颈部囊性淋巴管瘤9例，联体双胎4例，先天性膈疝5例，先天性巨结肠4例，脐膨出6例，A腹裂畸形4例，体蒂异常1例，马蹄内翻足5例)，3D-US检查真阳性率为89.66％(52／58)，特异性为98.11％(52／53)，3D-MRI检查真阳性率为93.10％(54／58)，特异性为98.18％，两者差异无统计学意义。但三维磁共振成像视野大，组织分辨率高，可以多平面观察胎儿表面结构和胎儿病变。讨论三维MRI可以清楚地对胎儿表面结构进行表面重建，能直观显示感兴趣结构的表面特征、立体形态和体表结构间的位置关系，可以作为二维成像的重要补充，尤其对于那些超声无法确诊或模棱两可的病例，在诊断方法上是一种有效的补充。
PartⅠThe study of feasibility of MRS of fetal brain
Objective To investigate the feasibility of single voxel ~1H magnetic resonancespectroscopy in fetal brain combination with fetal dynamic magnetic resonance imaging.
Methods 50 cases of fetuses were divided into three groups; polyhydramnios (n=6)、normal amount of amniotic fluid (n=21) and oligohydramnios (n=23). Gestatinal weeksranged from 20 weeks to 40 weeks, with median week of 32.6 weeks.Fetal dynamic MRIwere performed sagittally using SSFSE to observe fetal brain motion.On the basis ofsite-specific three planes, Point resolved spectroscopy sequence (PRESS) was used forsingel voxel ~1H MRS (TE=144ms) and the view of interest (VOI) was located in bothcerebral hemisphere at the level of semiovale centrum and basal ganglia with respiratorytrigger technique. Results The index of amniotic fluid of polohydramnios、normalamount of amniotic fluid and oligohydramnios were (8.0±0.7) cm、(5.7±1.4)cm and(3.8±1.4) cm, respectively.there is significantly statistical difference (F=17.95, P＜0.001).In group of polohydramnios, dynamic MRI can clearly display frequent motion withmultiple regional turnover, extention and turning of head. The resolution of MRS was low,each metabolin could not been distinguished Conclusion ~1H MRS in fetal brain is feasible.the achievement ratio is zero, In group of normal amount of amniotic fluid ,fetal headmotion decreased, each metabolin cound be distinguished with much noise.and theresolution is slightly low, the achievement ratio is 42.85% (9/21). In group ofoligohydramnios, fetal head motion is restricted and the achievement ratio is 95.65%(22/23),there is a significantly statistical difference between the group of oligohydramniosand normal amniotic fluid (X~2= 14.69, P＜0.05 ). Conclusion MRS of fetal head is feasibleand can play an important role in the evaluation of fetal brain development and diagnosisof disease.
PartⅡNormal MRS of fetal brain maturation
Objective To explore the metabolic level change of normal fetal brain with increasedgestational age. Methods 12 cases of gravidas during the second trimester and 23 cases ofgravidas during the third trimester consistant with the standard of investigation wereincluded into the study.Gestatinal weeks ranged from 20 weeks to 40 weeks, with medianweek of 34.6 weeks Cranial axial, sagittal and coronal planes T2WI were performed usingSSFSE within 1-2 days after US examinantion. On the basis of site -specific three planes,Point resolved spectroscopy sequence(PRESS) was used for singel voxel 1HMRS(TE=144ms and 35ms) using respiratory triggered technique and the view ofinterest(VOI) was located in both cerebral hemisphere at the level of semiovale centrumand basal ganglia .Measure value of spectra was automaticly provided, the metabolities inthe spectra included : N-acetylaspartate(NAA)、Choline、com-pounds(Cho)、Creatinecompounds(Cr)、myo-inositol(mI)、glutamate and glutamine(Glx) and so on. ResultsThere is no significantly statistical diffenence between the study group and the controlgroup about the head circumference、biparietal diameter、abdominal circumference andfemur length. Brain MRI and postnatal examination were normal ,Similar to the brain ofpostnatal neonates, MRS of the fetal brain showed three dominant resonance atTE=144ms,the highest choline peak at 3.2ppm, the creatirie peak at 3.0ppm and the NAApeak at 2.0ppm. Before 34 weeks, creatine peak is the second highest and after 34weeks,NAA is the sceond one. Five dominant resonance: MI, Cho, Cr, Glx and NAA wereobserved at the short echo time(TE= 35ms). During brain maturation in utero, at a longecho time (TE = 144 ms), a significant increase in NAA/S (P＜0.007, r2 =0. 20), and areduction in Cho/S (P=0.005, r2=0.22) is Seen.No significant increasein Cr/S (P = 0.96,r2=0.001) is detected. Lactate is not foundin normal, a significant increase in NAA/S (P=0.05, r2 = 0.21). No significant increase in Cr/s (P = 0.2, r2 = 0.049), A significant asignificant reduction in the MI/S (P = 0.045, r2 = 0.12) and Cho/S (P = 0.014, r2=0.17)ratio with progressing GA were observed at a short echo time. Conclusion 1H MRS infetal brain is feasible, the achievement ratio using respitory gating technique.
PartⅢDevelopment of normal fetal brain by MRI withsingle-shot fast spin echo and diffusion tensor imaging
Objective To evaluate normal maturation of the fetal brain combination with SSFSE andDTI. Methods The normal brains of 17 fetuses of 20-39 weeks gestational age wereexamined in utero with SSFSE series and DTI, gray and white matter differentiation,Gyrus maturation were evaluatedwith respect to gestational age, the data measured inADC maps and FA maps in different regions of normal fetal brain were analyzedstatistically. Results (1)At 20-23 weeks, the norma structure has been formed andtypical five layers were seen during the period .and three layers during 24-26weeks ,after27 weeks, only two layer were found.the brain had a smooth surface at about 20 weeksand lateral fissure could be found, the circuity and inner fovea of cortex were found withprogressive gestational weeks followed by gyrus and sulcus were formed and deepen, At30 weeks, sulcus and gyrus formation was observed in various regions of the brainparenchyma.(3)The mean ADC value was 1.83±0.3μm2/ms in frontal white matter,1.75±0.1μm2/ms in occipital white matter, 1.65±0.1μm2/ms in basal ganglia and2.9±0.6μm2/ms in cerebrospinal fluid, the difference between basal ganglia and both frontand occipital white matter was satistically significant (p＜0.05), a significant negativecorrelation between ADC value and gestational age could be found in frontal and occipitalwhite matter, as well as basal ganglia. Sensorimotor fibre could be tracted by the ventricleand bilateral sensorimotor could be clearly displayed in the hindlimb of interalcapsule .After 20 weeks, the fibre of genu and splenium could be tracted and FA value ofthem increase with progressive gestational weeks. Conclusion The change of brainparenchyma can be overallly and accurately assessed combination with SSFSE series andDTI.
PartⅣThree dimensional magnetic resonance imaging
Objective To investigate the value of three dimensional magnetic resonance imaging indisplaying the normal and abnormal structure of fetus compared with theultrasonography(US). Methods fifty pregnant women (gestational age rangedfrom20～38 weeks, with a mean of 28.6 weeks.) with fetal malformations were performedwith conventional prenatal US and MRI, sixty-two fetuses with anomalies wereconformed by autopsy and follow-up. Axial, sagittal and coronal SSFSE T_2WIexamination by a 1.5T GE superconduting MR scanner within 1～2 days after USexaminations were performed, 41 cases were performed three dimensional MRI with fastimage employing steady-state acquisition (FIESTA), 9 cases were performed threedimensional colon image with fast spoiled gradient echo(FSPGR),imaging postprocessingwere performed on SUN workstation,the MR and US appearances of fetal malformationswere compared to each other and autopsy. Results fifty-eight cases of fetalmalformations were verified by autopsy and follow-up ,includeing anacephaly(n=8),encephalomeningocele(n=3), micro-cephaly(n=1), cystic lymphangioma(n=9), conjoinedtwins(n=4), congenital diaphragmatic hernia(n=5), congenital (n=4), omphalocele (n=6),gastro-schisis(n=4), body stalk abnormality (n=1), equinovarus foot (n=5), the sensi-tivityand specifity of 3D-US and 3D-MRI were 89.66%(52/58) and 98.11% (52/53) versus93.10% and 98.18%, ther was no statistically significance between the two modalities, but3D-MRI have larger FOV, higher tissue resolution and can demonstrate fetal surface andlesions with multiple planes. Conclusions three dimensional MRI can perspicuouslyperform surfacing, directly display surface character ,solid figure and position relation.
目的结合磁共振动态成像探讨胎儿脑单体素磁共振波谱成像的可行性。材料和方法50例20—40孕周的胎儿按羊水量的多少分为三组(羊水量多组6例、正常羊水量组21例和羊水量少组23例)，磁共振电影动态成像采用SSFSE矢状面观察胎儿头部运动，磁共振波谱成像在胎儿三个正交平面定位基础上使用单体素点分辨波谱(PRESS)序列行单体素磁共振波谱采集(TE=144ms)，MRS采集使用呼吸触发技术。结果羊水量多组、正常羊水量组和羊水量少组的羊水指数分别为(8.0±0.7)cm、正常羊水量组和羊水量过少组的羊水指数分别为(5.7±1.4)cm和(3.8±1.4)cm，其差异有统计学意义(F=17.95，P＜0.001)，羊水过多组胎儿运动频繁，MR电影成像可以观察胎儿身体多部位的翻转、伸展和转头，磁共振波谱采集分辨力较低，代谢物在谱线上成锯齿状分裂的峰，波谱成功率为0(0／6)，羊水量正常组胎儿头部运动减少，磁共振波谱采集分辨力较低，代谢物在谱线上可以分辨，但是有明显的噪声，波谱成功率为42.58％(9／21)，羊水过少组胎头活动明显受限，磁共振波谱采集成功率高，代谢物在谱线上分辨率高．波谱成功率为95.65％(22／23)，正常羊水量组和羊水量少组成功率差异有显著性意义(X~2=4.21，P＜0.05)。结论胎儿脑氢质子波谱成像是可行的，在胎儿正常脑发育和疾病的诊断方面有重要的价值。
第二部分正常胎儿脑发育的磁共振波谱成像研究
目的探讨正常胎儿脑发育代谢物水平的变化。方法选取35例符合纳入标准的孕妇，其中中期妊娠12例，晚期妊娠23例，孕周20周～40周，平均孕周34.6周。超声检查后1-2天内使用单次激发快速自旋回波序列(SSFSE)行胎儿颅脑常规MR扫描，扫描平面包括胎儿脑轴面、冠状面和矢状面。在胎儿脑三个正交平面定位的基础上以基底节和半卵圆中心为兴趣区(VOI)分别使用呼吸触发技术，采用定点分辨波谱序列(PRESS)行单体素~1H MRS扫描，(TE分别为144ms和35ms)。MRS测量值由机器自动给出，所测定的代谢产物包括N-乙酰基天门冬氨酸(NAA)、胆碱复合物(Cho)、肌酸复合物(Cr)、肌醇(mI)、谷氨酸及谷氨酰胺(Glx)等，其他参数包括均方根噪声(RMS noise)和肌酸信号噪声比(Cr SNR)。选取与研究组各孕周段匹配的16例正常胎儿作对照。结果正常胎儿的头围，双顶径线、腹围、股骨长与对照组差异无统计学意义，脑部MRI和产后检查未发现异常，TE=144ms时，胎儿脑MRS可以检测出三个主要波峰，分别为Cho峰，位于3.2ppm，Cr峰，位于3.0ppm，NAA峰，位于2.02ppm。Cho峰为第一高峰，孕34周前，Cr峰为第二高峰，孕34周后，NAA峰为第二高峰，和出生后新生儿波谱类似，NAA峰在孕22周已经可以辨别，乳酸峰不能检测出或较低平，MI峰也可检测出，位于3.56ppm；TE=35ms，可以检测到Cho峰、Cr峰、MI峰、NAA峰和谷氨酸及谷氨酰胺峰(Glx)。随着孕周的增加，TE=144时，NAA／S增加(P=0.007，r~2=0.20)，Cho／S减小(P=0.005，r~2=0.22)，Cr／S随孕周变化不明显(P=0.96，r~2=0.001)．TE=35ms时，NAA／S增加(P=0.05，r~2=0.21)，Cho／S减小(P=0.014，r~2=0.17)，MI峰减小(P=0.045，r~2=0.12)，Cr／S随孕周变化不明显(P=0.2，r~2=0.049)。
第三部分正常胎儿脑发育的MRI和DTI研究
目的联合应用单次激发自旋回波序列和扩散张量成像观察正常胎儿脑发育表现。方法应用SSFSE序列和扩散张量成像检查17例20～39孕周的宫内正常胎儿大脑。根据胎龄评估脑回的成熟度、灰白质的分层情况、于ADC图和FA图测量不同部位脑组织平均扩散度和部分各向异性值，并对其进行统计分析。结果(1)胎儿20～23周时，脑结构形态基本形成，此孕周段可见大脑呈典型的5层结构，24～27孕周的胎儿呈典型的3层结构。27孕周后仅存留2层结构。(2)20周左右皮层光滑、外侧裂可见，随着胎龄的增加，皮层迂曲、内凹、脑回逐渐形成，随之脑沟也形成加深，30周左右脑回、脑沟比较明显。(3)额叶、枕叶脑白质和基底节ADC平均值分别是1.83±0.3μm~2／ms，1.75±0.1μm~2／ms和1.65±0.1μm~2／ms，脑脊液的平均ADC值是2.9±0.6μm~2／ms。基底节和额叶、枕叶脑白质平均ADC差异有统计学意义。额叶、枕叶和基底节平均ADC值随年龄增加而降低，与年龄呈线性负相关。(4)孕20周可以追踪到感觉运动纤维，位于脑室旁，定位于中间带区，随着孕周增加，双侧内囊后肢的感觉运动纤维可以清楚显示，呈头尾方向。孕20周以后可以追踪到胼胝体膝部和压部白质纤维，内囊后肢的FA值随孕周增加而增大。结论联合SSFSE序列和DTI成像可以准确全面评价胎儿大脑实质随着孕龄发育成熟过程中的变化规律。
第四部分胎儿三维磁共振成像研究
目的探讨三维磁共振成像在显示胎儿正常和异常结构方面的临床应用价值。方法50例超声诊断或怀疑胎儿先天畸形的孕妇行胎儿MRI，年龄21～32岁，平均25.4岁，胎龄20～38周，平均28.6周。MR成像采用单次激发快速自旋回波序列(SSFSE)，在孕妇腹部三平面定位基础上常规行胎儿颅脑和胸腹部轴面，冠状面和矢状面扫描，41例使用三维快速成像稳态进动序列(3D—FIESTA)行胎儿三维成像。9例使用三维扰相梯度回波序列(3D-FSPGR)序列行胎儿结肠三维成像，图像传输到工作站进行三维图像后处理。MRI检查于超声检查后1～2天进行，MRI检查后对胎儿进行尸检和随访观察。二维及三维超声和MR图像分别由两位超声科医师和两位放射科医师采用双盲法进行分析。结果经过尸检和随访发现胎儿畸形58例，其中单发畸形为44例，4例为2处畸形，2例为3处畸形，(其中无脑畸形8例，脑膜脑膨出3例，小头畸形1例，颈部囊性淋巴管瘤9例，联体双胎4例，先天性膈疝5例，先天性巨结肠4例，脐膨出6例，A腹裂畸形4例，体蒂异常1例，马蹄内翻足5例)，3D-US检查真阳性率为89.66％(52／58)，特异性为98.11％(52／53)，3D-MRI检查真阳性率为93.10％(54／58)，特异性为98.18％，两者差异无统计学意义。但三维磁共振成像视野大，组织分辨率高，可以多平面观察胎儿表面结构和胎儿病变。讨论三维MRI可以清楚地对胎儿表面结构进行表面重建，能直观显示感兴趣结构的表面特征、立体形态和体表结构间的位置关系，可以作为二维成像的重要补充，尤其对于那些超声无法确诊或模棱两可的病例，在诊断方法上是一种有效的补充。
PartⅠThe study of feasibility of MRS of fetal brain
Objective To investigate the feasibility of single voxel ~1H magnetic resonancespectroscopy in fetal brain combination with fetal dynamic magnetic resonance imaging.
Methods 50 cases of fetuses were divided into three groups; polyhydramnios (n=6)、normal amount of amniotic fluid (n=21) and oligohydramnios (n=23). Gestatinal weeksranged from 20 weeks to 40 weeks, with median week of 32.6 weeks.Fetal dynamic MRIwere performed sagittally using SSFSE to observe fetal brain motion.On the basis ofsite-specific three planes, Point resolved spectroscopy sequence (PRESS) was used forsingel voxel ~1H MRS (TE=144ms) and the view of interest (VOI) was located in bothcerebral hemisphere at the level of semiovale centrum and basal ganglia with respiratorytrigger technique. Results The index of amniotic fluid of polohydramnios、normalamount of amniotic fluid and oligohydramnios were (8.0±0.7) cm、(5.7±1.4)cm and(3.8±1.4) cm, respectively.there is significantly statistical difference (F=17.95, P＜0.001).In group of polohydramnios, dynamic MRI can clearly display frequent motion withmultiple regional turnover, extention and turning of head. The resolution of MRS was low,each metabolin could not been distinguished Conclusion ~1H MRS in fetal brain is feasible.the achievement ratio is zero, In group of normal amount of amniotic fluid ,fetal headmotion decreased, each metabolin cound be distinguished with much noise.and theresolution is slightly low, the achievement ratio is 42.85% (9/21). In group ofoligohydramnios, fetal head motion is restricted and the achievement ratio is 95.65%(22/23),there is a significantly statistical difference between the group of oligohydramniosand normal amniotic fluid (X~2= 14.69, P＜0.05 ). Conclusion MRS of fetal head is feasibleand can play an important role in the evaluation of fetal brain development and diagnosisof disease.
PartⅡNormal MRS of fetal brain maturation
Objective To explore the metabolic level change of normal fetal brain with increasedgestational age. Methods 12 cases of gravidas during the second trimester and 23 cases ofgravidas during the third trimester consistant with the standard of investigation wereincluded into the study.Gestatinal weeks ranged from 20 weeks to 40 weeks, with medianweek of 34.6 weeks Cranial axial, sagittal and coronal planes T2WI were performed usingSSFSE within 1-2 days after US examinantion. On the basis of site -specific three planes,Point resolved spectroscopy sequence(PRESS) was used for singel voxel 1HMRS(TE=144ms and 35ms) using respiratory triggered technique and the view ofinterest(VOI) was located in both cerebral hemisphere at the level of semiovale centrumand basal ganglia .Measure value of spectra was automaticly provided, the metabolities inthe spectra included : N-acetylaspartate(NAA)、Choline、com-pounds(Cho)、Creatinecompounds(Cr)、myo-inositol(mI)、glutamate and glutamine(Glx) and so on. ResultsThere is no significantly statistical diffenence between the study group and the controlgroup about the head circumference、biparietal diameter、abdominal circumference andfemur length. Brain MRI and postnatal examination were normal ,Similar to the brain ofpostnatal neonates, MRS of the fetal brain showed three dominant resonance atTE=144ms,the highest choline peak at 3.2ppm, the creatirie peak at 3.0ppm and the NAApeak at 2.0ppm. Before 34 weeks, creatine peak is the second highest and after 34weeks,NAA is the sceond one. Five dominant resonance: MI, Cho, Cr, Glx and NAA wereobserved at the short echo time(TE= 35ms). During brain maturation in utero, at a longecho time (TE = 144 ms), a significant increase in NAA/S (P＜0.007, r2 =0. 20), and areduction in Cho/S (P=0.005, r2=0.22) is Seen.No significant increasein Cr/S (P = 0.96,r2=0.001) is detected. Lactate is not foundin normal, a significant increase in NAA/S (P=0.05, r2 = 0.21). No significant increase in Cr/s (P = 0.2, r2 = 0.049), A significant asignificant reduction in the MI/S (P = 0.045, r2 = 0.12) and Cho/S (P = 0.014, r2=0.17)ratio with progressing GA were observed at a short echo time. Conclusion 1H MRS infetal brain is feasible, the achievement ratio using respitory gating technique.
PartⅢDevelopment of normal fetal brain by MRI withsingle-shot fast spin echo and diffusion tensor imaging
Objective To evaluate normal maturation of the fetal brain combination with SSFSE andDTI. Methods The normal brains of 17 fetuses of 20-39 weeks gestational age wereexamined in utero with SSFSE series and DTI, gray and white matter differentiation,Gyrus maturation were evaluatedwith respect to gestational age, the data measured inADC maps and FA maps in different regions of normal fetal brain were analyzedstatistically. Results (1)At 20-23 weeks, the norma structure has been formed andtypical five layers were seen during the period .and three layers during 24-26weeks ,after27 weeks, only two layer were found.the brain had a smooth surface at about 20 weeksand lateral fissure could be found, the circuity and inner fovea of cortex were found withprogressive gestational weeks followed by gyrus and sulcus were formed and deepen, At30 weeks, sulcus and gyrus formation was observed in various regions of the brainparenchyma.(3)The mean ADC value was 1.83±0.3μm2/ms in frontal white matter,1.75±0.1μm2/ms in occipital white matter, 1.65±0.1μm2/ms in basal ganglia and2.9±0.6μm2/ms in cerebrospinal fluid, the difference between basal ganglia and both frontand occipital white matter was satistically significant (p＜0.05), a significant negativecorrelation between ADC value and gestational age could be found in frontal and occipitalwhite matter, as well as basal ganglia. Sensorimotor fibre could be tracted by the ventricleand bilateral sensorimotor could be clearly displayed in the hindlimb of interalcapsule .After 20 weeks, the fibre of genu and splenium could be tracted and FA value ofthem increase with progressive gestational weeks. Conclusion The change of brainparenchyma can be overallly and accurately assessed combination with SSFSE series andDTI.
PartⅣThree dimensional magnetic resonance imaging
Objective To investigate the value of three dimensional magnetic resonance imaging indisplaying the normal and abnormal structure of fetus compared with theultrasonography(US). Methods fifty pregnant women (gestational age rangedfrom20～38 weeks, with a mean of 28.6 weeks.) with fetal malformations were performedwith conventional prenatal US and MRI, sixty-two fetuses with anomalies wereconformed by autopsy and follow-up. Axial, sagittal and coronal SSFSE T_2WIexamination by a 1.5T GE superconduting MR scanner within 1～2 days after USexaminations were performed, 41 cases were performed three dimensional MRI with fastimage employing steady-state acquisition (FIESTA), 9 cases were performed threedimensional colon image with fast spoiled gradient echo(FSPGR),imaging postprocessingwere performed on SUN workstation,the MR and US appearances of fetal malformationswere compared to each other and autopsy. Results fifty-eight cases of fetalmalformations were verified by autopsy and follow-up ,includeing anacephaly(n=8),encephalomeningocele(n=3), micro-cephaly(n=1), cystic lymphangioma(n=9), conjoinedtwins(n=4), congenital diaphragmatic hernia(n=5), congenital (n=4), omphalocele (n=6),gastro-schisis(n=4), body stalk abnormality (n=1), equinovarus foot (n=5), the sensi-tivityand specifity of 3D-US and 3D-MRI were 89.66%(52/58) and 98.11% (52/53) versus93.10% and 98.18%, ther was no statistically significance between the two modalities, but3D-MRI have larger FOV, higher tissue resolution and can demonstrate fetal surface andlesions with multiple planes. Conclusions three dimensional MRI can perspicuouslyperform surfacing, directly display surface character ,solid figure and position relation.
引文
[1] 夏黎明，杨文忠，邹明丽，等．胎儿主要器官的正常解剖和MR表现．中华放射学杂志，2005，39：1064-1067．
[2] 杨文忠，夏黎明，陈欣林，等．快速MR I对胎儿中枢神经系统先天畸形的诊断价值与超声对照研究．中华放射学杂志．2005，40：1139-1140
[3] Jung, JA Coakley, FA Vigneron, DB. Swanson, MG, et al Prostate Depiction at Endorectal MR Spectroscopic Imaging: Investigation of a Standardized Evaluation System Radiology 2004; 233:701-708
[4] Fenton BW, Lin CS, Macedonia C,Schellinger D, Ascher S (2001) The fetus at term: in utero volume-selected proton MR spectroscopy with a breathhold technique-a feasibility study.Radiology 219:563-566
[5] Kok RD, van den Berg PP, van den Bergh AJ, Nijland R, Heerschap A. Maturation of the human fetal brain as observed by ~1H MR spectroscopy. Magn Reson Med 2002; 48(4):611-6.
[6] Kok RD, van den Bergh AJ, Heerschap A, Nijland R, van denBerg PP. Metabolic information from the human fetal brain obtained with proton magnetic resonance spectroscopy. Am J Obstet Gynecol 2001; 185(5):1011-5.
[7] Kok, RD. van den Berg PP, van den Bergh AJ, Nijland R, MR Spectroscopy in the Human Fetus ~* Drs Lin and colleagues respond. Radiology, May 1, 2002; 223(2): 584-585.
[8] Arend Heerschap A, Kok RD, van den Berg PP, Antenatal proton MR spectr-oscopy of the human brain in vivo. Childs Nerv Syst (2003) 19:418-421
[9] Girard, N, Fogliarini C, Viola A,et al. MRS of normal and impaired fetal brain develop- ment Eur J Radiology, 57 (2006) 217-225
[10] Kato T, Nishina M, Matsushita K, Hori E, Mito T, Takashima S. Neuronal maturation and N-acetyl-L-aspartic acid development in human fetal and child brains. Brain Dev 1997：19：131-133．
[11] 李胜利．胎儿畸形产前超声诊断学．北京：人民军医出版社，2004：614-620．
[12] 程流泉，蔡幼铨，高元桂，梁燕，脑质子磁共振波谱检查PRESS与STEAM序列的对比，解放军医学杂志，2000，25：349-352
[13] 范国光，陈丽英，吴振华，等磁共振波谱在新生儿缺氧缺血性脑病中的应用 中华放射学杂志，，1999．33：388-342
[14] 胡越，黎规典，罗柏宁，等 磁共振成像新技术在胎儿中枢神经系统研究中的应用新医学2007，38：547-549
[15] Rijn, AMR, Groenendaal F, Stoutenbeek,P, van der Grond, J, Lactate in the foetal brain: detection and implications, Acta Pediatri 93: 937-940
[1] 李胜利．胎儿畸形产前超声诊断学，北京：人民军医出版社，2004：614-620．
[2] Girard, N, Fogliarini C, Viola A,et al. MRS of normal and impaired fetal brain development Eur J Radiology, 57 (2006) 217-225
[3] Kreis R, Hofmann L, Boesch C, BossiE, Huppi PS (2002) Brain metabolite composition during early human brain development as measured by quantitative in vivo 1H magnetic resonance spectroscopy. Magn Reson Med 48:949-95
[4] Girard, N, Gouny, SC Viola, G, et al, Assessment of Normal Fetal Brain Maturation In Utero by Proton Magnetic Resonance Spectroscopy
[5] Kato T, Nishina M, Matsushita K, Hori E. Mito T, Takashima S. Neuronal maturation and N-acetyl-L-aspartic acid development in human fetal and child brains. Brain Dev 1997;19:131-133.
[6] Kok RD, van den Berg PP, van den Bergh AJ, Nijland R, Heerschap A. Maturation of the human fetal brain as observed by ~1H MR spectroscopy. Magn Reson Med 2002; 48(4): 611-6.
[7] Kok RD, van den Bergh AJ, Heerschap A, Nijland R, van denBerg PP. Metabolic information from the human fetal brain obtained with proton magnetic resonance spectroscopy. Am J Obstet Gynecol 2001: 185(5): 1011-5.
[8] Kok, RD. van den Berg PP, van den Bergh AJ, Nijland R, MR Spectroscopy in the Human Fetus~* Drs Lin and colleagues respond. Radiology, May 1, 2002; 223(2): 584-585.
[9] Arend Heerschap A, Kok RD, van den Berg PP, Antenatal proton MR spectroscopy of the human brain in vivo. Childs Nerv Syst (2003) 19:418-421
[1] Lan, LM, Yamashita, Y, Tang, Y, et al Normal Fetal Brain Development: MR Imaging with a Half-Fourier Rapid Acquisition with Relaxation Enhancement Sequence, Radiology. 2000; 215: 205-210
[2] 李胜利．胎儿畸形前超声诊断学．北京：人民军医出版社，2004：614-620
[3] 夏黎明，杨文忠，邹明丽，等．胎儿主要器官的正常解剖和MR表现．中华放射学杂志．2005，39：1064-1067．
[4] Rados, M, Judas, M, Kostovic, I,In vitro MRI of brain development,Eur, J Radiology, 57: 187-198
[5] Schneider, JF, Confort-Gouny,S, Fur, YL, Diffusion-weighted imaging in normal fetal brain maturation, Eur Radiol (2007) 17:2422-2429
[6] Righini, A Bianchini,E, Parazzini, C, Apparent Diffusion Coefficient Determination in Normal Fetal Brain: A Prenatal MR Imaging Study.
[7] Kasprian, G, Brugger, PC, Weber, M, In utero tractography of fetal white matter development.
[8] Prayer.D, Brugger, PC, Prayer, L, Fetal MRI: techniques and protocols, Pediatr Radiol (2004) 34: 685-693.
[9] Girard.N,, Raybaud, C, Poncet, M, In Vivo MR Study of Brain Maturation in Normal Fetuses
[1] 徐辉雄，吕明德，张青萍，等，二维及三维超声评价胎儿畸形的对比研究。中华超声影像学杂志2002，11 (7)：330-332
[2] Kubik-Huch RA. Wildermuth S, Cettuzzi L, et al. Fetus and uteroplacental unit: fast MR imaging with three-dimensional reconstruction and volumetry feasibility study. Radiology 2001: 219:567-573.
[3] Prayer D, Brugger PC Prayer L. Fetal MRI: techniques and protocols. Pediatr Radiol (2004) 34:685-693
[4] Schierlitz L, Dumanli H, Robinson JN, et al (2001) Three-dimensional magnetic resonance imaging of fetal brains. Lancet 357:1177-1178
[5] Levine D, Three-dimensional Fetal MR Imaging:Will It Fulfill Its Promise? 219:313-315
[6] Scifo P, Cachia A, Boddaert N. et al (2004) Antenatal MR imaging for the study of fetus brain development, http://brainvisa.info/pdf/scifo-HBM03. Cited 11 Feb 2004
[7] Nobuhiko Hata,, Tom Wada, BS, Toshio Chiba,, Yoshiyuki Tsutsumi, Yoshiyuki Okada, Three-dimensional Volume Rendering of Fetal MR Images for the Diagnosis of Congenital Cystic Adenomatoid Malformation, Acad Radiol 2003: 10:309-312
[8] Zizka J, Elias P, Hodik K.Tintera J,Juttnerova V, Belobradek Z, et al Liver. meconium, haemorrhage: the value of T1-weighted images in fetal MRI
[9] Baba K, Okai T, Kozuma S, et al. Real-time processable three-dimensional US in obstetrics. Radiology, 1997, 203: 571-574.
[1] van der Knaap MS, van der Grond J, van Rijen PC, et al. Willemse K. Age-dependent changes in localized proton and phosphorus MR spectroscopy of the brain. Radiology 1990; 176: 509-515.
[2] Kok RD, van den Berg PP, van den Bergh AJ, et al. Maturation of the human fetal brain as observed by 1H MR spectroscopy. Magn Reson Med 2002; 48(4) : 611-6.
[3] Kok RD, van den Bergh AJ, Heerschap A, et al. Metabolic information from the human fetal brain obtained with proton magnetic resonance spectroscopy. Am J Obstet Gynecol 2001; 185(5) : 1011 -5.
[4] Fenton BW, Lin CS, Macedonia C, et al. The fetus at term: in utero volume-selected proton MR spectroscopy with a breath-hold technique-a feasibility study. Radiology 2001; 219(2):563 - 6.
[5] Kato T, Nishina M, Matsushita K, et al. Neuronal maturation and N-acetyl-1-aspartic acid development in human fetal and child brains. Brain Dev 1997; 19(2): 131 -3.
[6] Kreis R, Hofmann L, Boesch C, et al. Brain metabolit.e composition during early human brain development as measured by quantitativein vivo 1H magnetic resonance spectroscopy. Magn Reson Med 2002; 48:949-95.
[7] Ross B. Bluml S (2001) Magnetic resonance spectroscopy of the human brain. Anat Rec (New Anat) 265:54-84.
[8] Fenton BW, Lin CS, Ascher S, Macedonia C. Magnetic resonance spectroscopy to detect lecithin in amniotic fluid and fetal lung. Obstet Gynecol 2000; 95:457-460.
[9] Fenton BW, Lin CS, Seydel F, et al. Lecithin can be detected by volume selected proton MR spectroscopy using a 1.5 T whole body scanner: a potentially noninvasive method for the prenatal assessment of fetal lung maturity. Prenat Diagn 1998; 18: 1263-1266.
[10] Tyszka JM, Silverman JM. Navigated single voxel proton spectroscopy of the human liver. Magn Reson Med 1998; 39: 1-5.
[11] Kreis R, Ernst T, Ross BD. Development of the human brain: in vivo quantification of metabolite and water content with proton magnetic resonance spectroscopy. Magn Reson Med 1993; 30: 424-437.
[12] Bottomley PA. Spatial localization in NMR spectroscopy in vivo. Ann NY Acad Sci 1987; 508: 333-348.
[13] Frahm J, Merboldt KD, Haenicke W. Localized proton spectroscopy using stimulated echoes. J Magn Reson 1987; 72: 502-508.
[14] Fogliarini C, Chaumoitre K, Chapon F, et al. Assessmentof cortical maturation with prenatal MRI. Part Ⅰ: Normal cortical maturation. Eur Radiol 2005; 15: 1671-1685.
[15] Girard N, Raybaud C, Poncet M. In vivo MR study of brain maturation in normal fetuses. AJNR Am J Neuroradio 1995; 12: 407-413
[16] Righini A, Bianchini E, Parazzini C, et al. Apparent diffusion coefficient determination in normal fetal brain: a prenatal MR imaging study. AJNR Am J Neuroradiol 2003; 24:799-804.
[17] Prayer D, Prayer L. Diffusion-weighted magnetic resonance imaging of cerebral white matter development. Eur J Radiol. 2003; 45, 235-243.
[18] Eichler FS, Itoh R, Barker PB, et al. Proton MR spectroscopic and diffusion tensor brain MR imaging in X-linked adrenoleukodystrophy: initial experience. Radiology, 2002, 225: 245-252.
[19] Levine D, Barnes PD, Roertson RR, et al. Fast imaging of fetal central nervous system abnormalities. Radiology, 2003,229:51-61
[20] Coakley FV, Hricak H, Filly RF, et al complex fetal disorders:effect of MR imaging on management preliminary clinical experience . Radiology ,1999,213:691- 696
[21] Levine D, Barnes PD, Maclsen JR et al Fetal CNS anomalies revealed on ultrafast MR imaging AJR, 1999,172:813- 818
[2] 杨文忠，夏黎明，陈欣林，等．快速MR I对胎儿中枢神经系统先天畸形的诊断价值与超声对照研究．中华放射学杂志．2005，40：1139-1140
[3] Jung, JA Coakley, FA Vigneron, DB. Swanson, MG, et al Prostate Depiction at Endorectal MR Spectroscopic Imaging: Investigation of a Standardized Evaluation System Radiology 2004; 233:701-708
[4] Fenton BW, Lin CS, Macedonia C,Schellinger D, Ascher S (2001) The fetus at term: in utero volume-selected proton MR spectroscopy with a breathhold technique-a feasibility study.Radiology 219:563-566
[5] Kok RD, van den Berg PP, van den Bergh AJ, Nijland R, Heerschap A. Maturation of the human fetal brain as observed by ~1H MR spectroscopy. Magn Reson Med 2002; 48(4):611-6.
[6] Kok RD, van den Bergh AJ, Heerschap A, Nijland R, van denBerg PP. Metabolic information from the human fetal brain obtained with proton magnetic resonance spectroscopy. Am J Obstet Gynecol 2001; 185(5):1011-5.
[7] Kok, RD. van den Berg PP, van den Bergh AJ, Nijland R, MR Spectroscopy in the Human Fetus ~* Drs Lin and colleagues respond. Radiology, May 1, 2002; 223(2): 584-585.
[8] Arend Heerschap A, Kok RD, van den Berg PP, Antenatal proton MR spectr-oscopy of the human brain in vivo. Childs Nerv Syst (2003) 19:418-421
[9] Girard, N, Fogliarini C, Viola A,et al. MRS of normal and impaired fetal brain develop- ment Eur J Radiology, 57 (2006) 217-225
[10] Kato T, Nishina M, Matsushita K, Hori E, Mito T, Takashima S. Neuronal maturation and N-acetyl-L-aspartic acid development in human fetal and child brains. Brain Dev 1997：19：131-133．
[11] 李胜利．胎儿畸形产前超声诊断学．北京：人民军医出版社，2004：614-620．
[12] 程流泉，蔡幼铨，高元桂，梁燕，脑质子磁共振波谱检查PRESS与STEAM序列的对比，解放军医学杂志，2000，25：349-352
[13] 范国光，陈丽英，吴振华，等磁共振波谱在新生儿缺氧缺血性脑病中的应用 中华放射学杂志，，1999．33：388-342
[14] 胡越，黎规典，罗柏宁，等 磁共振成像新技术在胎儿中枢神经系统研究中的应用新医学2007，38：547-549
[15] Rijn, AMR, Groenendaal F, Stoutenbeek,P, van der Grond, J, Lactate in the foetal brain: detection and implications, Acta Pediatri 93: 937-940
[1] 李胜利．胎儿畸形产前超声诊断学，北京：人民军医出版社，2004：614-620．
[2] Girard, N, Fogliarini C, Viola A,et al. MRS of normal and impaired fetal brain development Eur J Radiology, 57 (2006) 217-225
[3] Kreis R, Hofmann L, Boesch C, BossiE, Huppi PS (2002) Brain metabolite composition during early human brain development as measured by quantitative in vivo 1H magnetic resonance spectroscopy. Magn Reson Med 48:949-95
[4] Girard, N, Gouny, SC Viola, G, et al, Assessment of Normal Fetal Brain Maturation In Utero by Proton Magnetic Resonance Spectroscopy
[5] Kato T, Nishina M, Matsushita K, Hori E. Mito T, Takashima S. Neuronal maturation and N-acetyl-L-aspartic acid development in human fetal and child brains. Brain Dev 1997;19:131-133.
[6] Kok RD, van den Berg PP, van den Bergh AJ, Nijland R, Heerschap A. Maturation of the human fetal brain as observed by ~1H MR spectroscopy. Magn Reson Med 2002; 48(4): 611-6.
[7] Kok RD, van den Bergh AJ, Heerschap A, Nijland R, van denBerg PP. Metabolic information from the human fetal brain obtained with proton magnetic resonance spectroscopy. Am J Obstet Gynecol 2001: 185(5): 1011-5.
[8] Kok, RD. van den Berg PP, van den Bergh AJ, Nijland R, MR Spectroscopy in the Human Fetus~* Drs Lin and colleagues respond. Radiology, May 1, 2002; 223(2): 584-585.
[9] Arend Heerschap A, Kok RD, van den Berg PP, Antenatal proton MR spectroscopy of the human brain in vivo. Childs Nerv Syst (2003) 19:418-421
[1] Lan, LM, Yamashita, Y, Tang, Y, et al Normal Fetal Brain Development: MR Imaging with a Half-Fourier Rapid Acquisition with Relaxation Enhancement Sequence, Radiology. 2000; 215: 205-210
[2] 李胜利．胎儿畸形前超声诊断学．北京：人民军医出版社，2004：614-620
[3] 夏黎明，杨文忠，邹明丽，等．胎儿主要器官的正常解剖和MR表现．中华放射学杂志．2005，39：1064-1067．
[4] Rados, M, Judas, M, Kostovic, I,In vitro MRI of brain development,Eur, J Radiology, 57: 187-198
[5] Schneider, JF, Confort-Gouny,S, Fur, YL, Diffusion-weighted imaging in normal fetal brain maturation, Eur Radiol (2007) 17:2422-2429
[6] Righini, A Bianchini,E, Parazzini, C, Apparent Diffusion Coefficient Determination in Normal Fetal Brain: A Prenatal MR Imaging Study.
[7] Kasprian, G, Brugger, PC, Weber, M, In utero tractography of fetal white matter development.
[8] Prayer.D, Brugger, PC, Prayer, L, Fetal MRI: techniques and protocols, Pediatr Radiol (2004) 34: 685-693.
[9] Girard.N,, Raybaud, C, Poncet, M, In Vivo MR Study of Brain Maturation in Normal Fetuses
[1] 徐辉雄，吕明德，张青萍，等，二维及三维超声评价胎儿畸形的对比研究。中华超声影像学杂志2002，11 (7)：330-332
[2] Kubik-Huch RA. Wildermuth S, Cettuzzi L, et al. Fetus and uteroplacental unit: fast MR imaging with three-dimensional reconstruction and volumetry feasibility study. Radiology 2001: 219:567-573.
[3] Prayer D, Brugger PC Prayer L. Fetal MRI: techniques and protocols. Pediatr Radiol (2004) 34:685-693
[4] Schierlitz L, Dumanli H, Robinson JN, et al (2001) Three-dimensional magnetic resonance imaging of fetal brains. Lancet 357:1177-1178
[5] Levine D, Three-dimensional Fetal MR Imaging:Will It Fulfill Its Promise? 219:313-315
[6] Scifo P, Cachia A, Boddaert N. et al (2004) Antenatal MR imaging for the study of fetus brain development, http://brainvisa.info/pdf/scifo-HBM03. Cited 11 Feb 2004
[7] Nobuhiko Hata,, Tom Wada, BS, Toshio Chiba,, Yoshiyuki Tsutsumi, Yoshiyuki Okada, Three-dimensional Volume Rendering of Fetal MR Images for the Diagnosis of Congenital Cystic Adenomatoid Malformation, Acad Radiol 2003: 10:309-312
[8] Zizka J, Elias P, Hodik K.Tintera J,Juttnerova V, Belobradek Z, et al Liver. meconium, haemorrhage: the value of T1-weighted images in fetal MRI
[9] Baba K, Okai T, Kozuma S, et al. Real-time processable three-dimensional US in obstetrics. Radiology, 1997, 203: 571-574.
[1] van der Knaap MS, van der Grond J, van Rijen PC, et al. Willemse K. Age-dependent changes in localized proton and phosphorus MR spectroscopy of the brain. Radiology 1990; 176: 509-515.
[2] Kok RD, van den Berg PP, van den Bergh AJ, et al. Maturation of the human fetal brain as observed by 1H MR spectroscopy. Magn Reson Med 2002; 48(4) : 611-6.
[3] Kok RD, van den Bergh AJ, Heerschap A, et al. Metabolic information from the human fetal brain obtained with proton magnetic resonance spectroscopy. Am J Obstet Gynecol 2001; 185(5) : 1011 -5.
[4] Fenton BW, Lin CS, Macedonia C, et al. The fetus at term: in utero volume-selected proton MR spectroscopy with a breath-hold technique-a feasibility study. Radiology 2001; 219(2):563 - 6.
[5] Kato T, Nishina M, Matsushita K, et al. Neuronal maturation and N-acetyl-1-aspartic acid development in human fetal and child brains. Brain Dev 1997; 19(2): 131 -3.
[6] Kreis R, Hofmann L, Boesch C, et al. Brain metabolit.e composition during early human brain development as measured by quantitativein vivo 1H magnetic resonance spectroscopy. Magn Reson Med 2002; 48:949-95.
[7] Ross B. Bluml S (2001) Magnetic resonance spectroscopy of the human brain. Anat Rec (New Anat) 265:54-84.
[8] Fenton BW, Lin CS, Ascher S, Macedonia C. Magnetic resonance spectroscopy to detect lecithin in amniotic fluid and fetal lung. Obstet Gynecol 2000; 95:457-460.
[9] Fenton BW, Lin CS, Seydel F, et al. Lecithin can be detected by volume selected proton MR spectroscopy using a 1.5 T whole body scanner: a potentially noninvasive method for the prenatal assessment of fetal lung maturity. Prenat Diagn 1998; 18: 1263-1266.
[10] Tyszka JM, Silverman JM. Navigated single voxel proton spectroscopy of the human liver. Magn Reson Med 1998; 39: 1-5.
[11] Kreis R, Ernst T, Ross BD. Development of the human brain: in vivo quantification of metabolite and water content with proton magnetic resonance spectroscopy. Magn Reson Med 1993; 30: 424-437.
[12] Bottomley PA. Spatial localization in NMR spectroscopy in vivo. Ann NY Acad Sci 1987; 508: 333-348.
[13] Frahm J, Merboldt KD, Haenicke W. Localized proton spectroscopy using stimulated echoes. J Magn Reson 1987; 72: 502-508.
[14] Fogliarini C, Chaumoitre K, Chapon F, et al. Assessmentof cortical maturation with prenatal MRI. Part Ⅰ: Normal cortical maturation. Eur Radiol 2005; 15: 1671-1685.
[15] Girard N, Raybaud C, Poncet M. In vivo MR study of brain maturation in normal fetuses. AJNR Am J Neuroradio 1995; 12: 407-413
[16] Righini A, Bianchini E, Parazzini C, et al. Apparent diffusion coefficient determination in normal fetal brain: a prenatal MR imaging study. AJNR Am J Neuroradiol 2003; 24:799-804.
[17] Prayer D, Prayer L. Diffusion-weighted magnetic resonance imaging of cerebral white matter development. Eur J Radiol. 2003; 45, 235-243.
[18] Eichler FS, Itoh R, Barker PB, et al. Proton MR spectroscopic and diffusion tensor brain MR imaging in X-linked adrenoleukodystrophy: initial experience. Radiology, 2002, 225: 245-252.
[19] Levine D, Barnes PD, Roertson RR, et al. Fast imaging of fetal central nervous system abnormalities. Radiology, 2003,229:51-61
[20] Coakley FV, Hricak H, Filly RF, et al complex fetal disorders:effect of MR imaging on management preliminary clinical experience . Radiology ,1999,213:691- 696
[21] Levine D, Barnes PD, Maclsen JR et al Fetal CNS anomalies revealed on ultrafast MR imaging AJR, 1999,172:813- 818