Decompressive craniectomies (DCs) are recommended for the treatment of raised intracranial pressure after acute ischaemic stroke. Some studies have demonstrated improved outcomes with early decompressive craniectomy (< 48 h from onset) in patients with malignant cerebral oedema following middle cerebral artery infarction. Limited data is available on suboccipital decompressive craniectomy after cerebellar infarction.

Our primary objective was to determine whether the timing of DCs influenced functional outcomes at 6 months. Our secondary objectives were to analyse whether age, gender, the territory of stroke, or preceding thrombectomy impacts functional outcome post-DC.

We conducted a retrospective study of patients admitted between January 2014 and December 2020 who had DCs post-acute ischaemic stroke. Data was collected from ICU electronic records, individual patient charts, and the stroke database.

Twenty-six patients had early DC (19 anterior/7 posterior) and 21 patients had late DC (17 anterior/4 posterior). There was no difference in the modified Rankin Scale (mRS) score of the two groups at 90 (p = 0.318) and 180 (p = 0.333) days post early vs late DC. Overall outcomes were poor, with 5 out of 46 patients (10.9%) having a mRS score ≤ 3 at 6 months. There was no difference in mRS scores between the patients who had hemicraniectomies for anterior circulation stroke (n = 35) and suboccipital DC for posterior circulation stroke (n = 11) (p = 0.594).

In this single-centre retrospective study, we found no significant difference in functional outcomes between patients who had early or late DC after ischaemic stroke.