Cranial defects often result from brain injuries, hemorrhages, strokes, or brain tumors. These conditions can increase pressure inside the skull, and if left untreated, may lead to dangerous complications like brain herniation. To manage this, a common procedure called decompressive craniectomy is performed to reduce intracranial pressure. While this surgery often stabilizes the patient's condition, it leaves a cranial defect that exposes the brain to external risks, including pressure fluctuations and potential damage. In severe cases, patients with larger defects may develop complications such as sinking skin flap syndrome.

Cranial reconstruction, also known as cranioplasty, is an important procedure to restore the skull's structure and protect the brain. This surgery can improve brain function, stabilize intracranial pressure, and enhance the patient's appearance. While cranioplasty is a standard neurosurgical procedure, it has a relatively high risk of complications compared to other brain surgeries. Common complications include infections, bleeding, hydrocephalus, and seizures. In severe cases, complications may lead to the failure of the reconstruction.

Understanding the factors that contribute to complications after cranioplasty is crucial for neurosurgeons to improve outcomes and reduce risks. This study aims to identify these factors and develop predictive models for postoperative complications of cranioplasty.

Cranial defects, often caused by conditions such as traumatic brain injuries, strokes, or brain tumors, present a significant clinical challenge. Decompressive craniectomy, frequently performed to manage increased intracranial pressure, leaves patients with cranial defects that require subsequent cranioplasty. Cranioplasty, while being a common neurosurgical procedure, has a higher complication rate compared to other cranial surgeries, warranting a deeper investigation into its risk factors.

In addition to identifying risk factors, this study aims to develop and validate predictive models for postoperative complications. Advanced statistical techniques, such as machine learning algorithms, will be used to assess the contribution of individual variables to complication risk.

By leveraging a large multi-center dataset, the study seeks to provide actionable insights into the prevention of postoperative complications. The results are expected to inform clinical decision-making, enhance patient outcomes, and improve the quality of perioperative care in neurosurgical practice.

Inclusion Criteria:

• Patients who underwent cranioplasty in the Department of Neurosurgery at Qilu Hospital of Shandong University, Tangdu Hospital of Air Force Medical University, or Daping Hospital, Army Military Medical University between January 1, 2015, and July 31, 2023
• Diagnosed with cranial defects
• Possessed complete and accessible electronic medical records
• Patients had no prior history of cranioplasty

Exclusion Criteria:

• Patients with a prior history of cranioplasty
• Severe comorbidities (such as serious cardiac, liver, kidney and immune system dysfunction)
• Congenital cranial defects
• Severe missing data

Patients with cranial defects who underwent their first cranioplasty in the Department of Neurosurgery at Qilu Hospital of Shandong University between January 1, 2015, and January 1, 2025, or at Tangdu Hospital of Air Force Medical University or Daping Hospital of the Army Medical University between January 1, 2015, and July 31, 2023.

All collected IPD

Beginning 1 year after publication with no end date

The individual participant data (IPD) and supporting information are available from the corresponding author upon reasonable request via email. Access will be provided to researchers with a scientifically sound proposal and for non-commercial purposes, in compliance with ethical guidelines.