Decompressive craniectomies, facts and fiction: a retrospective analysis of 526 cases.

BACKGROUND: The aim of this article was to review the clinical practice of "bone flap decompression" in Regional Neurosurgical Units with no particular protocol in use. METHODS: From January 2005 to December 2008, a retrospective and multicentre study was conducted on patients who were treated with decompressive craniectomy (DC) in seven departments of neurosurgery in Italy. This study included patients with traumatic brain injury, stroke, aneurysmal subarachnoid haemorrhage and cerebral arteriovenous malformations. Data were retrieved from individual medical records. RESULTS: We identified 526 patients with DC. Age was the most significant predictor factor of survival, together with pupil reactivity, time of decompression and size of the bone flap. The effect of age in predicting survival was so important that in patients over 65 years old we did not find any other significant factor related to survival. In younger patients, the survival rate was much better with a large bone flap (p = 0.01). Unfortunately, 57% of patients were decompressed with a bone flap of less than 12 cm in diameter. This was probably due to the association in 80% of cases between haematoma evacuation and decompression. CONCLUSIONS: The current practice in many centres is different from published papers. Decompression is common over the age of 65 years, is associated with haematoma evacuation and often the bone flaps are inadequate in terms of size.