Early external decompressive craniectomy with duroplasty improves functional recovery in patients with massive hemispheric embolic infarction: timing and indication of decompressive surgery for malignant cerebral infarction

BACKGROUND: Extensive cerebral hemispheric infarction associated with massive brain swelling is known as malignant infarction because of the rapid clinical deterioration and mortality as high as 80% unless appropriate treatment is performed. Decompressive craniectomy is an effective treatment, but patient selection, timing, functional recovery, and complications remain unclear. METHODS: Seventy-one patients with massive embolic hemispheric infarctions (infarct volume >200 cm(3)) associated with brain swelling were retrospectively divided into 3 groups according to the therapeutic modalities: 21 patients were treated conservatively (conservative group); 50 patients were treated by external decompressive craniectomy with duroplasty in 2 groups; 29 patients treated after the appearance of clinical and radiologic findings of brain herniation (late surgery group); and 21 patients treated before the onset of brain herniation (early surgery group). RESULTS: The mortality at 1 and 6 months in the conservative group were 61.9% and 71.4%, respectively. The mortality at 1 and 6 months in the late surgery group were significantly improved to 17.2% and 27.6%, respectively, (p < 0.01) and in the early surgery group were further improved to 4.8% and 19.1%, respectively. The functional recovery of the patients was estimated by the Glasgow Outcome Scale (GOS) and Barthel Index (BI) at 6 months after the ictus. The GOS scores of the early surgery group were significantly better than that of the late surgery group (p < 0.05). The mean BI score of the survivors in the late surgery group (26.9 +/- 30.4) was not significantly different from that of the conservative group (28.3 +/- 42.2), but was significantly improved in the early surgery group (52.9 +/- 34.2) compared with the late surgery group (p < 0.05). CONCLUSIONS: Early decompressive craniectomy with duroplasty before the onset of brain herniation should be performed to achieve satisfactory functional recovery if the infarct volume of the hemispheric cerebral infarction is more than 200 cm(3) and computed tomography on the second day after the ictus shows mass effect.