Postmortem fetal organ volumetry using magnetic resonance imaging and comparison to organ weights at conventional autopsy

Abstract

Objectives

Organ volume measurements: comparison between MRI and autopsy findings in infants following sudden unexpected death

“…The limited loss of basophilia9 and of organ weight indicates that our sample was relatively homogeneous and that maceration had a very limited effect on the measurements and no consequences at all on the trophicity (weight) of the organs. In the study by Breeze et al 4 on fetuses of variable age, the variable interval between death and MRI/autopsy might have influenced the assessment of volume and weight. Similarly, in the work by Thayvil et al ,5 the variable interval between death and MRI (1 to 9 days) might have led to errors due to tissue maceration.…”

“…Several recent works suggest that measurement of the volume of whole organs or segments thereof by imaging techniques might be an interesting method to follow organ growth and trophicity in patients with different pathologies 1–3. However, very few studies have compared the ‘virtual’ (by imaging techniques) and the real volumes of organs determined at autopsy 4 5…”

Fetal organ weight estimation by postmortem high‐field magnetic resonance imaging before 20 weeks' gestation

“…In the study by Breeze et al 15 , fetal density was similar between lung and liver but slightly different for the brain, whereas Thayyil et al 5 also found similar densities for various organs, with adrenal glands being less dense in comparison. None of these authors reported changes in organ density with advancing gestational age.…”

“…The same study showed that accuracy was lower when fetuses were < 20 weeks' gestation or < 300 g in weight. The weight of the organs measured varied between 6 and 161 g. In another study, fetal lung, brain and liver volumes were estimated at postmortem in a total of 25 fetuses at 16-40 weeks, again using conventional MRI at 1.5 T, and good correlation between volume estimate at MRI and weight estimate at postmortem was observed for the various organs studied 15 . Both previous studies mainly focused on fetuses above 20 weeks' gestation and, as for the study of Thayyil et al 5 , the smallest organ measured weighed about 6 g. In contrast, we focused on smaller fetuses, below 20 weeks' gestation, and thus on smaller organs.…”

Antenatal diagnosis and management of life-limiting conditions

“…59 It has been used to determine candidates for in-utero intervention such as fetal endoscopic tracheal occlusion. 3 Furthermore, advances in fetal imaging, particularly MRI, 60 and 3D ultrasound, now allow estimates to be made of fetal lung volume 61,62 which are reported to relate to determining the chances of postnatal survival. Parents must be counselled about the high risk of perinatal death even though survival in many centres may exceed 50% even with the largest hernias.…”