Large Size Hemicraniectomy Reduces Early Herniation in Malignant Middle Cerebral Artery Infarction.

BACKGROUND Decompressive hemicraniectomy (DHC) reduces mortality and improves outcome after malignant middle cerebral artery infarction (MMI) but early in-hospital mortality remains high between 22 and 33%. Possibly, this circumstance is driven by cerebral herniation due to space-occupying brain swelling despite decompressive surgery. As the size of the removed bone flap may vary considerably between surgeons, a size too small could foster herniation. Here, we investigated the effect of the additional volume created by an extended DHC (eDHC) on early in-hospital mortality in patients suffering from MMI. METHODS We performed a retrospective single-center cohort study of 97 patients with MMI that were treated either with eDHC (n = 40) or standard DHC (sDHC; n = 57) between January 2006 and June 2012. The primary study end point was defined as in-hospital mortality due to transtentorial herniation. RESULTS In-hospital mortality due to transtentorial herniation was significantly lower after eDHC (0 vs. 11%; p = 0.04), which was paralleled by a significantly larger volume of the craniectomy (p < 0.001) and less cerebral swelling (eDHC 21% vs. sDHC 25%; p = 0.03). No statistically significant differences were found in surgical or non-surgical complications and postoperative intensive care treatment. CONCLUSION Despite a more aggressive surgical approach, eDHC may reduce early in-hospital mortality and limit transtentorial herniation. Prospective studies are warranted to confirm our results and assess general safety of eDHC.