Subdural hemorrhage, intradural hemorrhage and hypoxia in the pediatric and perinatal post mortem: are they related? An observational study combining the use of post mortem pathology and magnetic resonance imaging.

摘要

BACKGROUND AND PURPOSE: Controversies exist over the causes of intradural hemorrhages (IDH), subdural hemorrhages (SDH) and hypoxia. SDH is a recognised finding at perinatal and pediatric autopsy. We describe the occurrence of IDH, SDH, and hypoxia in these deaths using a combined approach of post mortem magnetic resonance imaging (PM MRI), autopsy examination and histology. MATERIAL AND METHODS: Forty-two cases (1 day to 4 years, mean 6.9 months) underwent PM MRI and autopsy. Two further children (8 and 32 month of age) underwent autopsy only. MRI was conducted with a 1.5 T Magnet with fast spin-echo T2 weighted images, the images were assessed for the presence of SDH, hypoxia and structural abnormalities. Hypoxia was defined by a low signal in the ventrolateral thalami and peri-rolandic regions on MRI. Edema was interpreted as early acute hypoxia. On histology, hypoxia was defined by the presence of hypoxic neurons. RESULTS: IDH was seen histologically in 35/39 cases: diffuse in 17 and focal in 18. On the PM MRI focal IDH was not distinguished, and DIDH was only retrospectively suggested as a low signal around the venous sinuses or prominent venous sinuses, predominantly in the posterior falx and tentorium. Confident identification on the MRI was not possible. 12/17 cases with DIDH were less than a week old. SDH was seen in 11 cases on PM MRI. SDH was seen at autopsy in the same 11 cases and in the 2 cases where no PM MRI was performed. DIDH was seen in all these cases on histological examination (except in 1 case where the dura had not been sampled). Acute hypoxia was present in 14/42 cases both on histology and MRI. In 1 case changes of hypoxia were seen on MRI only. In 7 cases the hypoxia was seen on histology only. 12/13 cases with SDH had features of hypoxia. Of the cases with DIDH on histology 14/17 had hypoxia (on MRI, histology, or both). CONCLUSION: IDH and SDH are frequent findings in the perinatal and pediatric autopsy. SDH was associated with a DIDH and was also frequently associated with hypoxia. Focal IDH was not identified at the PM MRI; it was associated with hypoxia (on MRI and/or on histology) in less than a quarter of cases. Our results exhibit an association between IDH, SDH and hypoxia in children dying of natural causes. The highest incidence is seen in the perinatal period.