Dataset Information

Perfusion and apparent oxygenation in the human placenta (PERFOX).

ABSTRACT:

Purpose

To study placental function-both perfusion and an oxygenation surrogate ( T2* )-simultaneously and quantitatively in-vivo.

Methods

Fifteen pregnant women were scanned on a 3T MR scanner. For perfusion measurements, a velocity selective arterial spin labeling preparation module was placed before a multi-echo gradient echo EPI readout to integrate T2* and perfusion measurements in 1 joint perfusion-oxygenation (PERFOX) acquisition. Joint motion correction and quantification were performed to evaluate changes in T2* and perfusion over GA.

Results

The optimized integrated PERFOX protocol and post-processing allowed successful visualization and quantification of perfusion and T2* in all subjects. Areas of high T2* and high perfusion appear to correspond to placental sub-units and show a systematic offset in location along the maternal-fetal axis. The areas of highest perfusion are consistently closer to the maternal basal plate and the areas of highest T2* closer to the fetal chorionic plate. Quantitative results show a strong negative correlation of gestational age with T2* and weak negative correlation with perfusion.

Conclusions

A strength of the joint sequence is that it provides truly simultaneous and co-registered estimates of local T2* and perfusion, however, to achieve this, the time per slice is prolonged compared to a perfusion only scan which can potentially limit coverage. The achieved interlocking can be particularly useful when quantifying transient physiological effects such as uterine contractions. PERFOX opens a new avenue to elucidate the relationship between maternal supply and oxygen uptake, both of which are central to placental function and dysfunction.

SUBMITTER: Hutter J

PROVIDER: S-EPMC6825519 | biostudies-literature |

REPOSITORIES: biostudies-literature

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