Department of Medical Physics, Guy's & St Thomas' NHS Foundation Trust, London, UK.
Prenat Diagn. 2010 Mar;30(3):260-6. doi: 10.1002/pd.2463.
To assess the feasibility of foetal cerebral lactate detection and quantification by proton magnetic resonance spectroscopy ((1)H-MRS) in pregnancies at increased risk of cerebral hypoxia, using a clinical 1.5 T magnetic resonance imaging (MRI) system.
Localised (1)H-MRS was performed in four patients with pregnancies in their third trimester complicated by intrauterine growth restriction (IUGR). A long echo time (TE) of 288 ms was used to maximise detection and conspicuity of the lactate methyl resonance, together with a short TE MRS acquisition to check for the presence of lipid contamination. Individual peaks in the resulting spectra were measured, corrected for relaxation and referenced to the unsuppressed water signal to provide metabolite concentrations.
A resonance peak consistent with the presence of lactate was observed in all cases. In one subject, this was confounded by the identification of significant lipid contamination in the short TE MRS acquisition. The range of measured lactate concentrations was 2.0-3.3 mmol/kg and compared well with preterm neonatal MRS studies.
The non-invasive detection and quantification of foetal cerebral lactate by MRS is achievable on a clinical 1.5 T MRI system.
使用临床 1.5T 磁共振成像（MRI）系统，评估在脑缺氧风险增加的妊娠中通过质子磁共振波谱（1H-MRS）检测和定量胎儿脑内乳酸的可行性。
对 4 例妊娠晚期合并宫内生长受限（IUGR）的患者进行局部 1H-MRS 检查。采用长回波时间（TE）288ms，以最大限度地提高乳酸甲基共振的检测和可见度，并结合短 TE MRS 采集来检查是否存在脂质污染。对所得光谱中的单个峰进行测量，进行弛豫校正并参考未抑制的水信号，以提供代谢物浓度。
在所有病例中均观察到与乳酸存在一致的共振峰。在一个病例中，短 TE MRS 采集时发现存在明显的脂质污染，这使得该峰的识别变得复杂。所测量的乳酸浓度范围为 2.0-3.3mmol/kg，与早产儿 MRS 研究结果相符。
在临床 1.5T MRI 系统上，可以实现胎儿脑内乳酸的非侵入性检测和定量。
