OUTCOME OF EARLY CRANIOPLASTY IN TREPHINE SYNDROME OR PARADOXICAL BRAIN HERNIATION: SYSTEMATIC REVIEW

Abstract

Background: Cranioplasty (CP) following decompressive craniectomy (DC) restores skull integrity, improves intracranial physiology, and addresses complications such as sinking skin flap syndrome (SSS) and paradoxical brain herniation (PBH). Historically delayed for months to minimize infection risk, the optimal timing of CP remains controversial. Recent literature suggests that early CP (≤3 months) may improve neurological outcomes without increasing peri-operative complications.

Objective: This systematic review aimed to determine whether early CP improves neurological recovery and peri-operative safety compared with delayed CP, and to examine its role in reversing SSS and PBH.

Methods: A comprehensive search of PubMed, Scopus, Web of Science, and LILACS (January 2000–June 2025) identified comparative studies, observational cohorts, and case reports on CP timing. Two reviewers independently screened, extracted data, and assessed risk of bias using ROBINS-I and Newcastle–Ottawa scales. Heterogeneity precluded quantitative pooling; therefore, a narrative synthesis was performed.

Results: Twelve studies met inclusion criteria, including ten cohorts (n = 77–159 each) and two case reports. Definitions of early CP varied from <30 days to <90 days. Overall complication rates ranged from 19% to 44%. Most cohorts reported comparable infection rates between early and delayed CP, with some showing lower infection rates and significantly shorter operative times in early groups. Several studies suggested reduced hydrocephalus rates with ultra-early CP (<30 days). Neurological recovery improved after CP in both early and late groups, though earlier intervention sometimes yielded faster functional gains. Case reports and small series demonstrated rapid reversal of SSS and PBH following CP. Predictive modeling indicated that older age, low pre-operative GCS, larger defect area, and longer DC-to-CP intervals predicted worse outcomes.

Conclusion: Early CP appears safe and may provide advantages in operative efficiency, hydrocephalus prevention, and neurological recovery, particularly in selected patients after TBI. In the presence of SSS or PBH, expedited CP should be strongly considered. Large, prospective, and etiology-specific studies are needed to refine optimal timing.