Optimal timing of cranioplasty post-decompressive craniectomy in traumatic brain injury: a systematic review, meta-analysis, and overview of ongoing trials

Although cranioplasty (CP) is a frequently performed and simple procedure, complications are common, particularly bone flap resorption and infection. The timing of surgery is as an important contributory factor, but the optimal timing has not been clearly determined. We retrospectively investigated bone flap resorption and surgical site infection after CP to determine the optimal timing of surgery for reduction of complications. The study enrolled 126 patients who underwent decompressive craniectomy (DC) and subsequent CP. Patients with bone flap resorption or surgical site infection were analyzed as the "complication" group. Receiver operating characteristic curve analysis was performed and the Youden index was used to dichotomize "early CP" and "late CP" groups. Univariate and multivariate survival analyses were performed. The complication group included 42 patients. The Youden index was used to identify a cutoff value for the DC-CP interval of > 44days, and this was used to define early (< 45days) and late (≥ 45days) CP. Late CP was a significant risk factor in univariate and multivariate Cox regression analyses. This study showed that early CP before 45days after DC is associated with a lower rate of bone flap resorption and surgical site infection than late CP.

INTRODUCTION: Cranioplasty (CP) is crucial after decompressive craniectomy to restore cranial integrity in various intracranial pathologies. However, the optimal timing for CP remains a debate. Existing literature presents a spectrum of studies with varied timings and outcomes, yielding conflicting insights. METHODS: A database search was conducted until April 8th, 2024, to identify studies reporting outcomes of patients that underwent early and late CP, establishing a 90-day cutoff. Primary outcomes were hydrocephalus, infection, reoperation, subdural fluid collection, Activities of Daily Living (ADL) score and Barthel Index (BI). Complication rates of ultra-early CP (&lt;30 days) versus early CP were also evaluated. RESULTS: Among 561 articles screened, 28 met inclusion criteria, analyzing 3,273 patients across 23 cohorts, 4 case-series, and 1 case-control study. Early CP was associated with a higher rate of hydrocephalus (OR=1.82; 95%CI=[1.14,2.90],p=0.01). Furthermore, early CP showed a greater increase in ADL score (MD=17.15; 95%CI=[12.30,22.01], p=0.00001) and a significant increase in BI score from pre-CP to post-CP(MD=25.24; 95%CI=[15.40,35.09], p=0.0001) whereas, late CP demonstrated no significant difference(MD=-10.2; 95%CI=[-22.5,2.09], p=0.10). Late CP had a higher incidence of subdural fluid collection (OR=0.18; 95%CI=[0.04,0.93], p=0.04). Infection rate (OR=0.72; 95%CI=[0.43,1.21], p=0.21) reoperation (OR=1.72; 95%CI=[0.84,3.53], p=0.14) were not statistically significant. Ultra-early CP had comparable complication rates: hygroma (p=0.51), infection (p=0.47) and hydrocephalus (p=0.95) compared to early CP. CONCLUSIONS: This meta-analysis indicates that early CP may benefit subdural fluid collection, BI, and ADL scores, while late CP may improve post-CP hydrocephalus. However, our analysis was primarily limited by the use of observational studies. These findings underscore the critical role of CP timing in optimizing outcomes and minimizing complications, necessitating further clinical trials to inform neurosurgical guidelines.

Purpose Cranioplasty (CP) after decompressive craniectomy (DC) is routinely performed for reconstructive purposes and improves rehabilitation. However, the optimal timing of CP remains controversial. This study aimed to assess differences in clinical outcomes following different timings of CP in patients with traumatic brain injury. Materials and methods Patients with traumatic brain injury who underwent CP after DC in Zhongnan Hospital of Wuhan University from 1 January 2010 to 1 May 2017, and in Affiliated Hospital of Guizhou Medical University from 1 January 2015, to 1 May 2017, were retrospectively reviewed. According to the timing of CP, patients were divided into an ‘early group’ (3–6 months) and a ‘late group’ (6–12 months). The clinical characteristics of patients and postoperative complications occurred within 1-year follow-up were analysed. The neurological function was assessed with Barthel Index (BI). Results A total of 100 patients (58 cases in early group and 42 cases in late group) were included. The median interval between DC and CP was 135 days and 225 days in the early and late CP groups, respectively. The overall complication rate after CP was 16%, and no significant difference in complication rate was observed between the early and late CP groups (17.2% vs.14.3%, p = 0.69). The neurological function was improved in early CP group (pre-CP 85.77 ± 11.61 vs. post-CP 95.34 ± 9.02, p < 0.001, but not in late CP group (pre-CP 82.74 ± 22.82 vs. post-CP 88.93 ± 22.86, p = 0.22). In addition, a significantly higher proportion of patients in the early CP group showed neurological functional improvement in comparison with the late CP group (early vs. late: 74.1% vs. 57.1%, p = 0.04). Multivariate analysis further demonstrated that the timing of CP is an independent predictor for neurological outcomes (OR = 0.32, 95% CI 0.13–0.82, p = 0.02). Conclusion Early CP (3–6 months) following posttraumatic DC was associated with better neurological outcomes than late CP (>6 months).

A cranioplasty (CP) is often performed after decompressive craniectomy (DC) for cosmetic and protective reasons; however, the timing of CP needs to be better evaluated to maximize beneficial outcomes and neurological recovery. We investigated the effects and mechanisms of early CP compared to late CP on neurological recovery, from the perspective of cerebral blood flow (CBF). This study retrospectively reviewed 43 patients undergoing early (<12 weeks) or late (≥ 12 weeks) cranioplasty after DC. The CBF velocity was measured by transcranial Doppler ultrasonography and was analyzed prior to and after CP in every patient. Complications were recorded. The CBF velocity in the middle cerebral artery (MCA) ipsilateral to the CP was increased in both groups and was statistically different between groups (p < 0.05). On the contralateral side, however, the CBF in the MCA was increased in the early CP group, but not the late CP group. Change (expressed as delta, Δ) was defined as the difference in CBF velocity between pre- and postoperative status in the early and late CP groups. A statistically significant difference was detected in the Δ of MCA on the ipsilateral side between the early and late groups. There were no differences in the incidence of complications between groups. Our results show better post-DC improvements in the CBF of patients receiving CP < 12 weeks after DC, compared to those receiving CP ≥ 12 weeks after DC. Therefore, early CP has potential benefits for cerebral perfusion.

Background: Do alterations of cerebrospinal fluid dynamics secondary to decompressive craniectomy (DC) lead to hydrocephalus, and can this effect be mitigated by early cranioplasty (CP)? In this meta-analysis, we evaluated whether the timing of CP decreased the incidence of postoperative hydrocephalus.Methods: We performed a systematic search of PubMed/MEDLINE, Scopus, and the Cochrane databases using Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines for English language articles (1990–2020). We included case series, case–control, and cohort studies, and clinical trials assessing the incidence of hydrocephalus in adult patients undergoing early CP (within 3 months) versus late CP (after 3 months) after DC.Results: Eleven studies matched the inclusion criteria. The rate of postoperative hydrocephalus was not significantly different between the early (=96/1063; 9.03%) and late CP (=65/966; 6.72%) group (P = 0.09). Only in the three studies specifically reporting on the rate of hydrocephalus after DC performed to address traumatic brain injury (TBI) alone was there a significantly lower incidence of hydrocephalus with early CP (P = 0.01).Conclusion: Early CP (within 90 days) after DC performed in TBI patients alone was associated with a lower incidence of hydrocephalus. However, this finding was not corroborated in the remaining eight studies involving CP for pathology exclusive of TBI.

ObjectiveTo evaluate the effectiveness of early (<3 months) cranioplasty (CP) and late CP (>3 months) on post-operative complications in patients receiving decompressive craniotomy (DC) for traumatic brain injury (TBI).MethodsThe Cochrane Library, PubMed and EMBASE databases were systematically searched for studies published prior to May 21, 2017. A meta-analysis examined post-operative overall complication rates, infection rates, subdural fluid collection and operating times according to early and late CP.ResultsOf the initial 1675 references, five studies, all cohort, involving a total of 413 patients, were selected for the review. There was no difference between early and late CP in post-operative overall complication rate (RR=0.68, 95%CI [0.36, 1.29]) and the post-operative infection rate (RR=0.50, 95%CI [0.20, 1.24]) in patients receiving DC for TBI. However, there was a significant difference in post-operative subdural effusion (RR=0.24, 95%CI [0.07, 0.78]) and mean operative time (mean difference = −33.02 min, 95%CI [−48.19, −17.84]) both in favour of early CP.ConclusionsNo differences were found between early and late CP in post-operative overall complications and procedural related infections in patients receiving DC for TBI, but early CP reduced the complication of subdural effusion and the mean operating time. These findings need to be confirmed by large, randomised controlled trials.

Cranioplasty (CP) following decompressive craniectomy (DC) is a common neurosurgical procedure for cranial cosmesis and protection. There is uncertainty regarding the complication rates and potential benefits related to the timing of CP. To investigate the impact of the timing of CP on complication rates for different etiologies of DC. A retrospective chart review was performed of all CP cases between 2004 and 2018 for traumatic and nontraumatic indications of DC. Demographics, clinical characteristics, and complications were collected. Early and late CP were defined as replacement of the bone flap at ≤90 and >90 d following DC, respectively. A total of 278 patients were included, receiving 81 early and 197 late CPs. When analyzing all patients, early CP was associated with a statistically significant higher odds of any complication (odds ratio [OR]: 3.25, P<.001), reoperation (OR: 2.57, P=.019), hydrocephalus (OR: 6.03, P=.003), and symptomatic extra-axial collections (OR: 9.22, P=.003). Subgroup analysis demonstrated statistically significant higher odds of these complications only for the CP trauma subgroup, but not the nontrauma subgroup. The odds of complications postCP demonstrated a statistically significant decrease of 4.4% for each week after DC (Unit Odds Ratio [U-OR]: 0.956, P=.0363). In our retrospective series, early CP was associated with higher odds of postoperative complications compared to late CP in the trauma subgroup. Greater care should be taken in preoperative planning and increased vigilance postoperatively for complications with this potentially more vulnerable subpopulation. Future prospective controlled trials are needed to elucidate optimal timing for CP.

Role of timing of cranioplasty in improving Neurological functional outcome

Early Cranioplasty in Patients With Posttraumatic Decompressive Craniectomy and Its Correlation with Changes in Cerebral Perfusion Parameters and Neurocognitive Outcome

Brain protection and cosmetic aspects are the major indications of cranioplasty (CP) after decompressive craniectomy. CP can avoid the recurrence of brain damage, achieve the plastic effect, protect the patient from seizures, and relieve the syndrome of trephine. This was a prospective, observational study done over a period of 2 years from April 2017 to April 2019 in the Department of Neurosurgery at Sri Venkateswara Institute of Medical Sciences (SVIMS), Tirupati. Patients of age group 20-60 years who underwent CP after decompressive craniectomy for traumatic brain injury or cerebrovascular accidents with refractory intracranial hypertension were included. The study population was divided into two groups: early and late CP groups. Neurocognitive assessment was done 72 h before and 3 months after CP by mini-mental state examination (MMSE), Glasgow outcome score (GOS), and PGI battery of brain dysfunction (PGIBBD) scores. Cerebral glucose metabolism was assessed by 18F-FDG PET scan. In both early and late CP groups, there was a highly significant difference between the mean pre- and postoperative values of MMSE, GOS, and PGIBBD, suggesting significant improvement in neurocognitive parameters of patients postoperatively. There was no significant difference between early and late CP groups for mean standard uptake values (SUVs) on PET scan for both affected (P-value- 0.40) and nonaffected (P-value- 0.30) sides. CP improves the cerebral metabolism and neurocognitive outcome, weather it is done early or late.

How Early Can We Perform Cranioplasty for Traumatic Brain injury After Decompressive Craniectomy? A Retrospective Multicenter Study.

Cranial defects are common sequelae of decompressive craniectomy (DC) for traumatic brain injury (TBI) in pediatric patients, and their long-term growth dynamics remain poorly understood. This study aims to evaluate cranial defect size and its pattern of change with age following DC for TBI in the pediatric population. This single-center retrospective study included pediatric patients who underwent DC for TBI and later returned for cranioplasty (CP). Cranial defect size was evaluated at three time points—DC, CP, and follow-up—using multiple morphological measurements, including circumference, sectional area, and volume. Additionally, a control group of 208 individuals under 22 years of age was used to establish an intact skull growth curve. Cranial defect measurements, assessed through circumference, sectional area, and volume at three time points, showed no statistically significant changes (p = 0.54, 0.19, and 0.59), indicating stability with age. Subgroup analysis by implant material (autologous bone, titanium, and PEEK) also revealed no significant differences in defect morphology. The defective skull, defined as the cranial bones excluding the defect area, exhibited significant growth over time. Additionally, the intact skull growth curve, derived from the control group, exhibited a segmented pattern with three distinct growth phases: rapid growth during the first 5 years, followed by slower growth in the next 5 years, and a period of accelerated growth from age 11 onwards, with stabilization of skull volume at approximately 430 cm³ after age 17. This study provides novel insights into the stability of cranial defect size following DC for TBI in the pediatric population. The results suggest that, despite ongoing skull growth, cranial defect size remains stable with age, regardless of implant material. Furthermore, the study contributes a growth curve for the intact skull, offering valuable reference data for clinical decision-making in pediatric cranioplasty.

INTRODUCTION: Traumatic brain injury (TBI) is a common problem worldwide. Severe TBI is sometimes treated with decompressive craniectomy. Many patients who survive require tracheostomy. The decision to proceed with tracheostomy and at what time is often ambiguous. Existing methods for predicting which patients with neurologic insult will require tracheostomy are aimed at stroke and spontaneous intracranial hemorrhage (ICH). METHODS: We performed a retrospective review of adult patients who underwent decompressive craniectomy for severe TBI at the University of Kansas Medical Center between 2007 and 2020. RESULTS: 100% of patients who have GCS motor score of 4 or less on POD 5 required tracheostomy. 80% of patients with GCS motor score of 5 on POD 5 required tracheostomy. Setting the threshold at GCS motor score of 5 on POD 5 for recommending proceeding with tracheostomy results in 86.7% sensitivity, 91.7% specificity, and 90.5% PPV with area under the receiver operator curve of 0.9101. CONCLUSIONS: GCS motor score of 5 or less on POD 5 from decompressive craniectomy for TBI is predictive of need for tracheostomy.

Decompressive craniectomy (DC) is a surgical procedure to treat refractory increase in intracranial pressure. DC is frequently succeeded by cranioplasty (CP), a reconstructive procedure to protect the underlying brain and maintain cerebrospinal fluid flow dynamics. However, complications such as seizures, fluid collections, infections, and hydrocephalus can arise from CP. Our aim is to investigate these complications and their possible risk factors and to discuss whether early or late CP has any effect on the outcome. A single-center retrospective cohort study was performed, including patients who underwent CP after DC between January 2014 and January 2022. Relevant information was collected such as demographics, type of brain injury, materials used in CP, timing between DC and CP, and postoperative complications. Ultimately, 63 patients were included in our study. We also compared the complication rate between patients who underwent late CP after DC (>90 days) against patients who underwent early CP (<90 days). Most patients were male (78%). The sample median age was 29 years, with pediatric patients, accounting for 36% of the samples. Overall complication rate was 57% and they were seizure/epilepsy in 50% of the patients, fluid collection (28%), infections (25%), posttraumatic hydrocephalus (17%), and bone defect/resorption (3%). Twenty-two percent of patients with complications required reoperation and underwent a second CP. The median (interquartile range) duration between the craniotomy and the CP was 56 (27-102) days, with an early (≤3 months) percentage of 68%. We found no significant difference between early (≤3 months) and late (>3 months) CP regarding complication rates. Despite CP being a simple procedure, it has a considerable rate of complications. Therefore, it is important that surgeons possess adequate knowledge about such complications to navigate these challenges more effectively.

This review discusses some of the recent advances and current controversies in the acute clinical management of traumatic brain injury (TBI) and spinal cord injury (SCI). Several key risk factors for adverse prognosis in TBI have been identified, including female sex. In the management of intracranial hypertension antibiotic impregnated intraventricular catheters have been found to reduce the risk for infection, and new studies have examined the roles of mannitol, hyperventilation, and hypothermia. Moderate hypothermia has also been found to improve outcome. Hyperoxia is now being explored as a treatment option for improving brain metabolism in TBI. That acute SCI continues to be a challenging diagnosis is supported by a recent study that showed that 9.1% of SCIs are missed initially. The diagnosis and management of spinal instability has been studied in different patient groups. In SCI without radiographic abnormality, the presence of normal magnetic resonance imaging findings was associated with a good prognosis. New studies in the field of early decompression and the prevention of thromboembolism in SCI have also been published. Guidelines for the management of acute SCI recommend methylprednisolone and GM-1 ganglioside only as options. In neurotrauma some established treatments have been re-examined and their efficacy proven, whereas others that were once considered the standard of care in SCI, such as methylprednisolone, have been questioned. Large multicenter trials are needed to assess treatments such as early decompression in SCI and decompressive craniectomy in TBI. A truly effective neuroprotective therapy in neurotrauma remains elusive.