難治性頭蓋内高血圧に対する拡大開頭術と標準減圧開頭術の比較：系統的レビューおよびメタアナリシス

Raised intracranial pressure can have devastating consequences on mortality and outcome after acute brain injury. Decompressive craniectomy (DC) is an established surgical procedure for controlling refractory intracranial hypertension, though this requires subsequent cranioplasty. Expansive craniotomy (EC) techniques, where the bone flap is returned but only partially fixed in place, have been developed to avoid the need for cranioplasty. However, comparative safety and efficacy is not well-defined.

A systematic review to identify studies comparing EC to DC was performed in accordance with PRISMA guidelines, including all study types except systematic/scoping reviews. Meta-analysis was performed for three outcomes (mortality, acute reoperation rate, and Glasgow Outcome Scale (GOS)).

29 studies met the inclusion criteria, and are summarised in narrative review. Eight studies were included in meta-analysis: two randomised controlled trials (RCT) and six case-control studies. Meta-analysis found no significant difference in mortality. EC was associated with improved GOS (mean difference 0.44, p < 0.05), though this may be attributable to selection bias. There was a marginal increase in early additional surgery rates associated with EC (risk difference 0.08, p = 0.05). Risk of bias was moderate to high across included studies.

Current evidence cannot robustly inform clinical decision-making on the use of EC. Based upon reports of success of EC, EC appears to be a valid alternative to DC in selected cases, though greater acute reoperation rates owing to inadequate decompression is a risk. Overall there is strong support for an appropriately-powered RCT to robustly evaluate EC.