Syndrome of the trephined: clinical spectrum, risk factors, and impact of cranioplasty on neurologic recovery in a prospective cohort

Functional outcome after late cranioplasty after decompressive craniectomy: a single-center retrospective study

OBJECTIVE

The best time for cranioplasty (CP) after decompressive craniectomy (DC) is controversial, and there are no authoritative guidelines yet. Both complications as well as outcome may depend on the timing of CP. The aim of this single-center study was to evaluate the impact of late CP on procedural safety as well as on patient outcome.

METHODS

All patients receiving CP at a tertiary university medical center between 01/2015 and 12/2022 were included retrospectively. Patients' conditions were assessed according to the modified Rankin Scale (mRS) prior to CP and 6 months after. Baseline characteristics, indication for DC, time from DC to CP, and postoperative complications according to the Landriel Ibañez Classification were analyzed.

RESULTS

CP was performed in 271 patients who previously underwent DC due to traumatic brain injury (25.5%), ischemic stroke (29.5%), aneurysmal subarachnoid hemorrhage (26.9%), or intracerebral hemorrhage (18.1%). The median interval between DC and CP was 143 days (interquartile range 112-184 days). Receiver operating characteristic analysis revealed a cut-off of 149 days, where CP performed within 149 days after DC led to an improvement on mRS after CP (p = 0.001). In multivariate analysis, additional rehabilitation after and better mRS before CP were independently associated with improvement of outcome. The rate of complications was similar between early and late CP (24.8% and 25.4%, respectively, p = 0.562).

CONCLUSIONS

Late cranioplasty is a safe procedure. The outcome was improved when additional rehabilitation was performed after cranioplasty and was not associated with the timing of cranioplasty.

Predictive factors influencing outcome of early cranioplasty after decompressive craniectomy: a outcome prediction model study

Objective

The timing of cranioplasty (CP) has become a widely debated topic in research, there is currently no unified standard. To this end, we established a outcome prediction model to explore the factors influencing the outcome of early CP. Our aim is to provide theoretical and practical basis for whether patients with skull defects after decompressive craniectomy (DC) are suitable for early CP.

Methods

A total of 90 patients with early CP after DC from January 2020 to December 2021 were retrospectively collected as the training group, and another 52 patients with early CP after DC from January 2022 to March 2023 were collected as the validation group. The Nomogram was established to explore the predictive factors that affect the outcome of early CP by Least absolute shrinkage analysis and selection operator (LASSO) regression and Logistic regression analysis. Receiver operating characteristic (ROC) curve was used to evaluate the discrimination of the prediction model. Calibration curve was used to evaluate the accuracy of data fitting, and decision curve analysis (DCA) diagram was used to evaluate the benefit of using the model.

Results

Age, preoperative GCS, preoperative NIHSS, defect area, and interval time from DC to CP were the predictors of the risk prediction model of early CP in patients with skull defects. The area under ROC curve (AUC) of the training group was 0.924 (95%CI: 0.867-0.980), and the AUC of the validation group was 0.918 (95%CI, 0.842-0.993). Hosmer-Lemeshow fit test showed that the mean absolute error was small, and the fit degree was good. The probability threshold of decision risk curve was wide and had practical value.

Conclusion

The prediction model that considers the age, preoperative GCS, preoperative NIHSS, defect area, and interval time from DC has good predictive ability.

The Use of Histoacryl Injections to Treat Subgaleal Cerebrospinal Fluid Collection After Cranioplasty

BACKGROUND AND OBJECTIVES

Cranioplasty is an important and basic operation in the neurosurgical field. An emergency craniectomy is performed to control malignant cerebral edema. If the patient survives, cranioplasty is performed to restore the skull defect; however, subgaleal cerebrospinal fluid collection (SCSFC) may occur. The authors aimed to identify risk factors for postoperative SCSFC and effective solutions with the subgaleal Histoacryl injection.

METHODS

From January 2020 to December 2022, 154 craniectomies were performed at our hospital to relieve significant cerebral edema after traumatic brain injury; of these, 67 patients survived and underwent cranioplasty. Ten cases of postcranioplasty SCSFC were identified, among which 6 received subgaleal Histoacryl injection.

RESULTS

Among the 10 SCSFC cases, 3 resolved with compression after cerebrospinal fluid aspiration, and 1 resolved after revision surgery and dural closure. Histoacryl injection was attempted for the other 6 patients. A single injection was sufficient for SCSFC resolution in 3 patients. One patient required 2 injections, and another required 3 injections. The remaining patient underwent epiduroperitoneal shunt surgery because of SCSFC persistence after 3 Histoacryl injections. Five of 6 patients (83.3%) showed an improvement of more than 80% after Histoacryl injection.

CONCLUSION

Subgaleal Histoacryl injection is not considered a fundamental treatment for postoperative SCSFC but can be a successful alternative treatment.

Risk Factors for Seizures After Titanium Cranioplasty: Five-Year Experience from a Single Institution

OBJECTIVE

Seizures are one of the complications that can occur after cranioplasty (CP). In some regions, titanium mesh remains the material of choice for CP. However, risk factors for seizures after titanium CP have been less studied. The purpose of this study was to identify potential risk factors for early seizures (≤7 days) and late seizures (>8 days) after titanium CP in a single institution.

METHODS

A retrospective review was conducted of 241 consecutive patients who received titanium CP at the First Affiliated Hospital of Harbin Medical University from January 2016 to December 2020. Univariate and multivariable logistic regression analyses were performed to determine the independent risk factors for new-onset seizures after titanium CP.

RESULTS

Fifteen patients (6.22%) experienced early post-CP seizures, and late post-CP seizures were observed in 81 patients (33.61%). A flaccid concave cranial defect (P = 0.042) was associated with early post-CP seizures, whereas hypertension (P < 0.001) was the only significant predictor for late seizures after titanium CP.

CONCLUSIONS

Seizure is a common complication after titanium CP, especially in patients who do not receive prophylactic antiepileptic drugs before the procedure. Risk factors for new-onset seizures at different periods after titanium CP were found to be different. In addition, radiologic factors before titanium CP may play a role in early new-onset seizures after titanium CP and should not be ignored.

Medical comorbidities in patients with prolonged disorder of consciousness: A narrative review

BACKGROUND

A few studies specifically addressed medical comorbidities (MCs) in patients with severe acquired traumatic or non-traumatic brain injury and prolonged disorders of consciousness (pDoC; i.e., patients in vegetative state/unresponsive wakefulness syndrome, VS/UWS, or in minimally conscious state, MCS).

OBJECTIVE

To provide an overview on incidence of MCs in patients with pDoC.

METHODS

Narrative review on most impacting MCs in patients with pDoC, both those directly related to brain damage (epilepsy, neurosurgical complications, spasticity, paroxysmal sympathetic hyperactivity, PSH), and those related to severe disability and prolonged immobility (respiratory comorbidities, endocrine disorders, metabolic abnormalities, heterotopic ossifications).

RESULTS

Patients with pDoC are at high risk to develop at least one MC. Moderate or severe respiratory and musculoskeletal comorbidities are the most common MCs. Epilepsy and PSH seem to be more frequent in patients in VS/UWS compared to patients in MCS, likely because of higher severity in the brain damage in VS. Endocrine metabolic, PSH and respiratory complications are less frequent in traumatic etiology, whereas neurogenic heterotopic ossifications are more frequent in traumatic etiology. Spasticity did not significantly differ between VS/UWS and MCS and in the three etiologies. MCs are associated with higher mortality rates, worse clinical improvement and can impact accuracy in the clinical diagnosis.

CONCLUSIONS

The frequent occurrence of several MCs requires a specialized rehabilitative setting with high level of multidisciplinary medical expertise to prevent, appropriately recognize and treat them. Comprehensive rehabilitation could avoid possible progression to more serious complications that can negatively impact clinical outcomes.

Comparison of Perioperative and Long-term Outcomes Following PEEK and Autologous Cranioplasty: A Single Institution Experience and Review of the Literature

OBJECTIVE

Three-dimensionally (3D) printed polyether-ether-ketone (PEEK) implants are a relatively novel option for cranioplasty that have recently gained popularity. However, there is ongoing debate with respect to material efficacy and safety compared to autologous bone grafts. The purpose of this study was to offer our institution's experience and add to the growing body of literature.

METHODS

A single-institution retrospective analysis of patients undergoing cranioplasties between 2016 and 2021. Patients were divided into PEEK and autologous cranioplasty cohorts. Parameters of interest included patient demographics as well as perioperative (<3 months postoperative) and long-term outcomes (>3 months postoperative). A P value < 0.05 was considered statistically significant.

RESULTS

A total of 31 patients met inclusion criteria (PEEK: 15, Autologous: 16). Mean age of total cohort was 48.9 years (range 19-82 years). Modified Frailty Index (mFI) revealed greater rate of comorbidities among the Autologous group (P = 0.073), which was accounted for in statistical analyses. Multiple logistic regression model revealed significantly higher rate of surgical site infection in the Autologous cohort (31.3% vs. 0%, P = 0.011). Minor complications were similar between groups, while the Autologous group experienced significantly more major postoperative complications (50%) versus PEEK (13.3%) (P = 0.0291). Otherwise perioperative and long term complication profiles were similar between groups. Additionally, generalized linear model demonstrated both cohorts had similar mean hospital length of stay (LoS) (Autologous: 16.1 vs. PEEK: 10.7 days).

CONCLUSIONS

PEEK cranioplasty implants may offer more favorable perioperative complication profiles with similar long-term complication rates and hospital LoS compared to autologous bone implants. Future studies are warranted to confirm our findings in larger series, and further examine the utility of PEEK in cranioplasty.

Clinical Outcomes After Cranioplasty With Titanium Mesh, Polyetheretherketone, or Composite Bone Cement: A Retrospective Study

Cranioplasty is a common neurosurgical procedure; however, the optimal material choice remains controversial. At the time of this writing, autologous bone, the preferred choice for primary cranioplasty, has a high incidence of complications such as infection and resorption, thus requiring frequent use of synthetic materials. Therefore, this study aimed to compare the clinical benefits of titanium mesh (Ti), polyetheretherketone (PEEK), and composite bone cement (CBC) in cranioplasty to provide a clear selection basis for clinicians and patients. This study retrospectively collected data from 207 patients who underwent cranioplasty with Ti (n=129), PEEK (n=54), and CBC (n=24) between January 2018 and December 2020 at Henan Provincial People's Hospital. Postoperative follow-up information after 6 months was used to compare the long-term effects of the 3 materials on the patients. There were no significant differences in the overall complication rate after cranioplasty among the 3 materials. However, subcutaneous effusion was more frequent with PEEK (24.07%) and CBC (20.83%) than with Ti (2.33%). Second, there were no significant differences in the increase in Glasgow Outcome Scale and Karnofsky Performance Status scores after cranioplasty among the 3 materials. Finally, we found that PEEK had the highest patient satisfaction and hospitalization cost, whereas the opposite was true for Ti. Although the surgical outcomes of the 3 implant materials were similar, an examination of clinical outcomes such as patient satisfaction showed significant differences, deepening people's perceptions of the 3 materials.

Custom 3D-Printed External Cranial Orthotic for Prevention and Treatment of Syndrome of the Trephined

Syndrome of the Trephined (SoT) is a frequently misunderstood and underdiagnosed outcome of decompressive craniectomy, especially in cases of trauma. The pressure gradient between atmospheric pressure and the sub-atmospheric intracranial pressure results in a sinking of the scalp overlying the craniectomy site. This gradually compresses the underlying brain parenchyma. This parenchymal compression can disrupt normal autoregulation and subsequent metabolism, yielding symptoms ranging from headaches, dizziness, altered behavior to changes in sensation, and difficulty with ambulation, coordination, and activities of daily living. We present a case of SoT treated with a 3D-printed custom polycarbonate external cranial orthotic that allowed us to re-establish this pressure gradient by returning the cranium to a closed system. The patient demonstrated subjective improvement in quality of life and his symptoms. This was consistent with the re-expanded brain parenchyma on CT imaging.

Outcome and management of decompressive hemicraniectomy in malignant hemispheric stroke following cardiothoracic surgery

Management of malignant hemispheric stroke (MHS) after cardiothoracic surgery (CTS) remains difficult as decision-making needs to consider severe cardiovascular comorbidities and complex coagulation management. The results of previous randomized controlled trials on decompressive surgery for MHS cannot be generally translated to this patient population and the expected outcome might be substantially worse. Here, we analyzed mortality and functional outcome in patients undergoing decompressive hemicraniectomy (DC) for MHS following CTS and assessed the impact of perioperative coagulation management on postoperative hemorrhagic and cardiovascular complications. All patients that underwent DC for MHS resulting as a complication of CTS between June 2012 and November 2021 were included in this observational cohort study. Outcome was determined according to the modified Rankin Scale (mRS) score at 1 and 3-6 months. Clinical and demographic data, anticoagulation management and postoperative hemorrhagic and thromboembolic complications were assessed. In order to evaluate a predictive association between clinical and radiological parameters and the outcome, we used a multivariate logistic regression analysis. Twenty-nine patients undergoing DC for MHS after CTS with a female-to-male ratio of 1:1.9 and a median age of 60 (IQR 49-64) years were identified out of 123 patients undergoing DC for MHS. Twenty-four patients (83%) received pre- or intraoperative substitution. At 30 days, the in-hospital mortality rate and neurological outcome corresponded to 31% and a median mRS of 5 (5-6), which remained stable at 3-6 months [Mortality: 42%, median mRS: 5 (4-6)]. Postoperatively, 15/29 patients (52%) experienced new hemorrhagic lesions and Bayesian logistic regression predicting mortality (mRS = 6) after imputing missing data demonstrated a significantly increased risk for mortality with longer aPPT (OR = 13.94, p = .038) and new or progressive hemorrhagic lesions after DC (OR = 3.03, p = .19). Notably, all but one hemorrhagic lesion occurred before discontinued anticoagulation and/or platelet inhibition was re-initiated. Despite perioperative discontinuation of anticoagulation and/or platelet inhibition, no coagulation-associated cardiovascular complications were noted. In conclusion, Cardiothoracic surgery patients suffering MHS will likely experience severe neurological disability after DC, which should remain a central aspect during counselling and decision-making. The complex coagulation situation after CTS, however, should not per se rule out the option of performing life-saving surgical decompression.

Decompressive Hemicraniectomy in the Stroke Patient

Decompressive hemicraniectomy (DHC) is a life-saving procedure involving removal of large portions of the skull to relieve intracranial pressure in patients with space occupying cerebral edema such as traumatic brain injury (TBI) and stroke. Although the procedure has been shown to decrease mortality in patients, the risk of severe disability is significant. Quality of life, not just survival, following DHC has emerged as an important consideration when the decision is made to perform a DHC.

Osteoprotegerin-eluting nanoparticulate mineralized collagen scaffolds improve skull regeneration

Custom synthesis of extracellular matrix (ECM)-inspired materials for condition-specific reconstruction has emerged as a potentially translatable regenerative strategy. In skull defect reconstruction, nanoparticulate mineralized collagen glycosaminoglycan scaffolds (MC-GAG) have demonstrated osteogenic and anti-osteoclastogenic properties, culminating in the ability to partially heal in vivo skull defects without the addition of exogenous growth factors or progenitor cell loading. In an effort to reduce catabolism during early skull regeneration, we fabricated a composite material (MCGO) of MC-GAG and recombinant osteoprotegerin (OPG), an endogenous anti-osteoclastogenic decoy receptor. In the presence of differentiating osteoprogenitors, MCGO demonstrated an additive effect with endogenous OPG limited to the first 14 days of culture with total eluted and scaffold-bound OPG exceeding that of MC-GAG. Functionally, MCGO exhibited similar osteogenic properties as MC-GAG, however, MCGO significantly reduced maturation and resorptive activities of primary human osteoclasts. In a rabbit skull defect model, MCGO scaffold-reconstructed defects displayed higher mineralization as well as increased hardness and microfracture resistance compared to non-OPG functionalized MC-GAG scaffolds. The current work suggests that MCGO is a development in the goal of reaching a materials-based strategy for skull regeneration.

Can Cranioplasty Be Considered a Tool to Improve Cognitive Recovery Following Traumatic Brain Injury? A 5-Years Retrospective Study

Cranioplasty (CP) is a neurosurgical intervention of skull repairing following a decompressive craniectomy. Unfortunately, the impact of cranioplasty on cognitive and motor function is still controversial. Fifteen TBI subjects aged 26–54 years with CP after decompressive craniectomy were selected in this observational retrospective study. As per routine clinical practice, a neuropsychological evaluation carried out immediately before the cranioplasty (Pre CP) and one month after the cranioplasty (T0) was used to measure changes due to CP surgery. This assessment was performed each year for 5 years after discharge in order to investigate long-term cognitive changes (T1-T5). Before cranioplasty, about 53.3% of subjects presented a mild to severe cognitive impairment and about 40.0% a normal cognition. After CP, we found a significant improvement in all neuropsychological test scores. The more significant differences in cognitive recovery were detected after four years from CP. Notably, we found significant differences between T4 and T0-T1, as well as between T5 and T0-T1-T2 in all battery tests. This retrospective study further suggests the importance of CP in the complex management of patients with TBI showing how these patients might improve their cognitive function over a long period after the surgical procedure.