Microhemorrhages in the Brains of Mountaineers who Survived High Altitude Cerebral Edema (HACE)

Abstract

Ziele: Brain MRI during high altitude illness is not easy. Usually no scanner is around during the illness. Post-mortem exams showed multiple micro-hemorrhages (MH) in brains of HACE victims. We hypothesized MH may also occur in non-lethal HACE and deposits of hemosiderin indicative of previous MH can be found in HACE survivors. Methode: We performed brain MRI in 36 mountaineers: HACE survivors (n=10), subjects who had suffered from severe acute mountain sickness (AMS, n=11), subjects who had had high altitude pulmonary edema (HAPE, n=8) and mountaineers with repeated high altitude exposure (>7000m without additional oxygen), but without HACE (n=7). MR protocol included susceptibility-weighted imaging, which is very sensitive in detection of previous MH. Ergebnis: MH were almost exclusively found in the group of HACE survivors. Distribution: most MH were found in the corpus callosum, especially the splenium. In severe HACE MH were also found in cerebral hemispheres. MH were detectable years after HACE. Schlussfolgerung: Cerebral Microhemorrhages were found almost exclusively and consistently in the brains of HACE surviors. They are found predominantly in the Corpus callosum and are detectable years after HACE. This diagnostic sign has not been previously described and may become an important conerstone in the diagnosis of high altitude cerebral edema (HACE).