Post-craniectomy hydrocephalus in adult traumatic brain injury patients: a systematic review and meta-analysis of risk factors and outcome.

Traumatic Brain Injury (TBI) is a major cause of death, disability, and healthcare expenses worldwide. Decompressive craniectomy (DC) is a critical surgery used when there is uncontrollable swelling in the brain following a TBI. Research has shown that 27.4% of patients who underwent DC for severe TBI developed hydrocephalus, leading to a significant impact on their quality of life and long-term outlook. We conducted a review of hydrocephalus risk factors in adult TBI patients who underwent DC to better understand the factors contributing to this condition. The comprehensive search strategy covered PubMed, Scopus, Embase, and Web of Science databases from inception to June 2024. The search terms "Craniectomy AND Hydrocephalus AND Trauma* and Decompress*" were applied to titles, abstracts, and keywords. Out of 887 publications found, 591 remained after removing duplicates. After reviewing titles and abstracts, 480 articles were excluded. Of the remaining 111 articles, 87 were excluded for various reasons, leaving 22 for the meta-analysis. The cumulative sample size was 2888, and the incidence of hydrocephalus was 20.5%. We analyzed 28 variables and of them, 13 were associated with hydrocephalus, Subrachnoid hemorrhage (OR:1.75), Intraventricular hemorrhage (OR: 2.49), At least one pupil dilation (OR: 2.01), Preoperative GCS < 6, Craniectomy Margin Distance from Midlineless than 21 mm, size of craniectomy greater than 106.75 cm2, TCHBV greater than 69, bilateral craniectomy (OR: 3.75), Postoperative intracranial infection (OR: 2.7), Postoperative Cerebral infarction (OR: 2.74), interhemispheric Hygroma (OR: 5.53), contralateral Hygroma (OR: 4.18), and bilateral Hygroma (OR: 2.55). Hydrocephalus following DC is notably linked to an adverse outcome (Glasgow Outcome Scale 1, 2, 3 OR: 4.06). After decompressive craniectomy, hydrocephalus significantly affects traumatic brain injury recovery. Our analysis found that the craniectomy margin distance from the midline less than 21 mm is a modifiable risk factor for hydrocephalus development. Other significant risk factors will help diagnose at-risk patients, address hydrocephalus promptly, and ultimately improve patient outcomes.