Minimally Invasive Alternative Approaches to Pterional Craniotomy: A Systematic Review of the Literature

OBJECTIVE: Minimally invasive alternatives to the pterional craniotomy include the minipterional and the supraorbital craniotomy (SOC). The latter is performed via either an eyebrow or an eyelid skin incision. The purpose of this systematic review was to analyze the type and the incidence of approachrelated complications of these so-called "keyhole craniotomies". METHODS: We review pertinent articles retrieved by search in the PubMed/Medline database. Inclusion criteria were all full-text articles, abstracts, and posters in English, up to 2016, reporting clinical results. RESULTS: A total of 105 articles containing data on 5837 surgeries performed via a minipterional or either of the 2 variants of the SOC met the eligibility criteria. Pain on mastication was the most commonly reported approach-related complication of the minipterional approach, and occurred in 7.5% of cases. Temporary palsy of the frontal branch of the facial nerve and temporary supraorbital hypesthesia were associated with the SOC eyebrow variant, and occurred in 6.5%, respectively in 3.6% of cases. Transient postoperative periorbital edema and transient ophthalmoparesis occurred in 36.8% and 17.4% of cases, respectively, when the SOC was performed via an eyelid skin incision. The risk of occurrence of the latter 2 complications was related to the removal of the orbital rim, which is an obligatory part of the SOC approach through the eyelid but optional with the SOC eyebrow variant. CONCLUSIONS: Each of the 3 keyhole approaches has a specific set and incidence of approach-related complications. It is essential to be aware of these complications to make the safest individual choice.