Post-traumatic hydrocephalus following decompressive hemicraniectomy: Incidence and risk factors in a prospective cohort of severe TBI patients

Outcomes of Cranioplasty: A Single-Center Experience

Background Cranioplasty (CP) is a common cranial reconstructive procedure. It is performed after craniectomy due to various causes such as relieving increased intracranial pressure, infection, and tumor infiltration. Although CP is an easy procedure, it is associated with a high rate of complications. We aimed to retrospectively investigate the outcomes of CP at the King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Jeddah (KAMC-J). Methods This is a retrospective observational study that included all patients who had CP (first time or redo) at KAMC-J from 1st January 2010 to 31st December 2020. Patients with congenital cranial malformation were excluded.  Result A total of 68 patients underwent CP. Of those, 23 (34%) had complications. The most common complication was infection (10.3%). Twelve of the 23 patients had major complications that necessitated reoperation. Of those 12, six underwent redo CP; three out of these six patients had further complications which were also managed surgically. On bivariate analysis, cranial defects over 50 cm² were associated with a higher rate of both infection and hydrocephalus (p=0.018) while the frontal site was associated with a higher rate of infection (p=0.014). Moreover, traumatic brain injury as an etiology was exclusively associated with post-cranioplasty hydrocephalus (p=0.03).  Conclusion Patients undergoing CP after craniectomy are prone to a considerably high rate of adverse outcomes. The overall rate of complications in this study was 34%, with an infection rate of 10.3% and a 1.5% mortality rate. Consistent with other studies, larger cranial defects as well as frontal sites have a higher rate of infection.

Factors associated with post traumatic hydrocephalus following decompressive craniectomy: A single-center experience

Background

A decompressive craniectomy (DC) is a surgical procedure sometimes utilized to manage refractory intracranial hypertension following severe traumatic brain injury (sTBI). The previous studies have established a relationship between DC and post traumatic hydrocephalus (PTH). This study aimed to identify the factors responsible for developing shunt-amenable PTH in patients who underwent DC following sTBI.

Methods

A review of a prospectively collected database of all patients admitted with severe TBI in a tertiary neurosurgical center in North-west England between January 2012 and May 2022 was performed. PTH was defined as evidence of progressive ventricular dilatation, clinical deterioration, and/or the eventual need for cerebrospinal fluid diversion (i.e., a ventriculoperitoneal shunt). Statistical analysis was carried out using IBM SPSS versus 28.0.1.

Results

Sixty-five patients met the eligibility criteria and were included in the study. The mean age of the PTH group was 31.38 ± 14.67, while the mean age of the non-PTH group was slightly higher at 39.96 ± 14.85. No statistically significant difference was observed between the two groups' mechanisms of traumatic injury (P = 0.945). Of the predictors investigated, cerebellar hematoma (and contusions) was significantly associated with PTH (P = 0.006).

Conclusion

This study concludes that cerebellar hematoma (and contusions) are associated with developing PTH in patients undergoing DC.

[Surgical treatment of patients with skull defects and cerebrospinal fluid flow disorders after previous decompressive craniectomy]

Decompressive craniectomy (DC) is performed for refractory intracranial hypertension following severe traumatic brain injury, vascular and oncological diseases. This fact increases the number of patients with extensive and giant skull defects. Cerebrospinal fluid (CSF) flow disorders after DC are often accompanied by ventriculomegaly. However, only some patients with ventriculomegaly have hydrocephalus and require CSF bypass procedures. Differentiation of post-traumatic hydrocephalus requiring surgical treatment and atrophic dilation of ventricular system «ex vacuo» caused by brain injury is still an important issue. Skull sealing as a way to normalize CSF circulation and eliminate hydrocephalus is also an open question. Currently, there is no unified approach to patients with extensive and giant cranial defects combined with post-traumatic hydrocephalus. There is no unified algorithm for sequence of reconstructive and CSF bypass operations in these patients. Literature data on risks of infectious complications for different surgical strategies are controversial.

Next-generation personalized cranioplasty treatment

Decompressive craniectomy (DC) is a surgical procedure, that is followed by cranioplasty surgery. DC is usually performed to treat patients with traumatic brain injury, intracranial hemorrhage, cerebral infarction, brain edema, skull fractures, etc. In many published clinical case studies and systematic reviews, cranioplasty surgery is reported to restore cranial symmetry with good cosmetic outcomes and neurophysiologically relevant functional outcomes in hundreds of patients. In this review article, we present a number of key issues related to the manufacturing of patient-specific implants, clinical complications, cosmetic outcomes, and newer alternative therapies. While discussing alternative therapeutic treatments for cranioplasty, biomolecules and cellular-based approaches have been emphasized. The current clinical practices in the restoration of cranial defects involve 3D printing to produce patient-specific prefabricated cranial implants, that provide better cosmetic outcomes. Regardless of the advancements in image processing and 3D printing, the complete clinical procedure is time-consuming and requires significant costs. To reduce manual intervention and to address unmet clinical demands, it has been highlighted that automated implant fabrication by data-driven methods can accelerate the design and manufacturing of patient-specific cranial implants. The data-driven approaches, encompassing artificial intelligence (machine learning/deep learning) and E-platforms, such as publicly accessible clinical databases will lead to the development of the next generation of patient-specific cranial implants, which can provide predictable clinical outcomes. STATEMENT OF SIGNIFICANCE: Cranioplasty is performed to reconstruct cranial defects of patients who have undergone decompressive craniectomy. Cranioplasty surgery improves the aesthetic and functional outcomes of those patients. To meet the clinical demands of cranioplasty surgery, accelerated designing and manufacturing of 3D cranial implants are required. This review provides an overview of biomaterial implants and bone flap manufacturing methods for cranioplasty surgery. In addition, tissue engineering and regenerative medicine-based approaches to reduce clinical complications are also highlighted. The potential use of data-driven computer applications and data-driven artificial intelligence-based approaches are emphasized to accelerate the clinical protocols of cranioplasty treatment with less manual intervention and shorter intraoperative time.

Risk Factors and Incidence of Epilepsy after Severe Traumatic Brain Injury

We determined the incidence of post-traumatic epilepsy after severe traumatic brain injury. Of 392 patients surviving to discharge, cumulative incidence of post-traumatic epilepsy was 25% at 5 years and 32% at 15 years, an increase compared with historical reports. Among patients with one late seizure (>7 days post-trauma), the risk of seizure recurrence was 62% after 1 year and 82% at 10 years. Competing hazards regression identified age, decompressive hemicraniectomy, and intracranial infection as independent predictors of post-traumatic epilepsy. Patients with severe traumatic brain injury and a single late post-traumatic seizure will likely require long-term antiseizure medicines. ANN NEUROL 2022;92:663-669.

Factors Affecting Development of Infection After Implantation of Ventriculoperitoneal Shunts in Patients with Posttraumatic Hydrocephalus

BACKGROUND

Patients with posttraumatic hydrocephalus (PTH) have a high incidence of infection after ventriculoperitoneal shunt (VPS). In this study, we investigated different risk factors affecting infection after VPS in PTH patients.

METHODS

Clinical data on PTH patients with VPS in Shaanxi Provincial People's Hospital from March 2012 to November 2020 were collected and analyzed retrospectively. We evaluated the relevance of patients' sex, age, cause of hydrocephalus, severity of hydrocephalus, types of hydrocephalus, hypertension, diabetes, decompressive craniectomy (DC), abdominal surgery, and duration of VPS surgery in the development of postoperative infection. Predictive values of different risk factors for the development of postoperative infection were analyzed using the receiver operating characteristic curve.

RESULTS

Shunt infection occurred in 38 patients (10.2% of cases). We found that patients >60 years of age with severe hydrocephalus, hypertension, diabetes, DC, and duration of surgery for VPS >60 minutes were at a significantly higher risk of developing an infection after VPS (P < 0.05). The area under the curve was used to predict shunt infection using age (0.611), severe hydrocephalus (0.589), hypertension (0.641), diabetes (0.657), DC (0.640), and duration of operation (0.600) as independent risk factors. The area under the curve of shunt infection predicted by whole index was 0.871.

CONCLUSIONS

Age, severe hydrocephalus, hypertension, diabetes, DC, as well as duration of operation for VPS (>60 minutes) were factors that significantly and independently correlated with the incidence of infection after VPS. The receiver operating characteristic curve that we have developed can predict the occurrence of shunt infection.

Severe Traumatic Brain Injury in children-paradigm of decompressive craniectomy compared to a historic cohort

PURPOSE

Traumatic brain injury (TBI) is one of the leading causes of death and disability in children. Medical therapy remains limited, and decompressive craniectomy (DC) is an established rescue therapy in case of elevated intracranial pressure (ICP). Much discussion deals with clinical outcome after severe TBI treated with DC, while data on the pediatric population is rare. We report our experience of treating severe TBI in two different treatment setups at the same academic institution.

METHODS

Forty-eight patients (≤ 16 years) were hospitalized with severe TBI (GCS ≤ 8 points) between 2008 and 2018 in a pediatric intensive care unit (ICU) at a specialized tertiary pediatric care center. Data on treatment, clinical status, and outcome was retrospectively analyzed. Outcome data included Glasgow Outcome Scale (GOS) at 3-, 12-, and 36-month follow-up. Data was compared to a historic cohort with 53 pediatric severe TBI patients treated at the same institution in a neurointensive care unit between 1996 and 2007. Ethical approval was granted (EA2/076/21).

RESULTS

Between 2008 and 2018, 11 patients were treated with DC. Compared to the historic cohort, patients were younger and GCS was worse, while in-hospital mortality and clinical outcome remained similar. A trend towards more aggressive EVD placement and the internal paradigm change for treatment in a specialized pediatric ICU was observed.

CONCLUSIONS

In children with severe TBI treated over two decades, clinical outcome was comparable and mostly favorable in two different treatment setups. Consequent therapy is warranted to maintain the positive potential for favorable outcome in children with severe TBI.

Complications from Multimodal Monitoring Do not Affect Long-Term Outcomes in Severe Traumatic Brain Injury

BACKGROUND

Invasive neuromonitoring is a mainstay of modern management of severe traumatic brain injury (TBI). Complication rates of neuromonitor placement are widely reported, but their effects on long-term outcomes are less studied. We evaluated the association of neuromonitor complications on long-term outcomes in a prospective severe TBI cohort.

METHODS

We reviewed 599 patients with severe TBI from November 2002 through 2018 for neuromonitor-associated hemorrhage and infection. We compared outcome differences between patients with and without neuromonitoring-associated complications using the Glasgow Outcomes Scale (GOS) at 3, 6, 12, and 24 months post trauma. When analyzing neuromonitoring infections, we removed all patients who expired before discharge as early mortality was associated with reduced infection rates.

RESULTS

Neuromonitor-associated hemorrhage occurred in 62 out of 534 patients with post placement imaging (11.6%) and was increased in patinets who underwent a craniotomy (24% vs. 11%, P = 0.005). Clinical outcomes did not differ in patients with neuromonitor-associated hemorrhage. Neuromonitor-associated infection occurred in 30 of 389 patients (7.7%) who survived to discharge. Infection was associated with worse outcomes at 3 months (P = 0.03), where the proportion of patients with favorable outcomes (P = 0.02) was decreased despite similar mortality (P = 0.24). Patients with an infection recovered by 6 months, at which point there were no differences in total GOS or rates of favorable outcomes then or at later time points (P > 0.26). Neuromonitor-associated infection was associated with increased length of stay (P = 0.01) and depressed skull fractures (P = 0.03) but did not affect rates of shunting (P = 0.99).

CONCLUSIONS

Complications of neuromonitoring in severe TBI are associated with delayed recovery but not long-term outcomes.

Outcome Prediction in Patients with Severe Traumatic Brain Injury Using Deep Learning from Head CT Scans

Background After severe traumatic brain injury (sTBI), physicians use long-term prognostication to guide acute clinical care yet struggle to predict outcomes in comatose patients. Purpose To develop and evaluate a prognostic model combining deep learning of head CT scans and clinical information to predict long-term outcomes after sTBI. Materials and Methods This was a retrospective analysis of two prospectively collected databases. The model-building set included 537 patients (mean age, 40 years ± 17 [SD]; 422 men) from one institution from November 2002 to December 2018. Transfer learning and curriculum learning were applied to a convolutional neural network using admission head CT to predict mortality and unfavorable outcomes (Glasgow Outcomes Scale scores 1-3) at 6 months. This was combined with clinical input for a holistic fusion model. The models were evaluated using an independent internal test set and an external cohort of 220 patients with sTBI (mean age, 39 years ± 17; 166 men) from 18 institutions in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury (TRACK-TBI) study from February 2014 to April 2018. The models were compared with the International Mission on Prognosis and Analysis of Clinical Trials in TBI (IMPACT) model and the predictions of three neurosurgeons. Area under the receiver operating characteristic curve (AUC) was used as the main model performance metric. Results The fusion model had higher AUCs than did the IMPACT model in the prediction of mortality (AUC, 0.92 [95% CI: 0.86, 0.97] vs 0.80 [95% CI: 0.71, 0.88]; P < .001) and unfavorable outcomes (AUC, 0.88 [95% CI: 0.82, 0.94] vs 0.82 [95% CI: 0.75, 0.90]; P = .04) on the internal data set. For external TRACK-TBI testing, there was no evidence of a significant difference in the performance of any models compared with the IMPACT model (AUC, 0.83; 95% CI: 0.77, 0.90) in the prediction of mortality. The Imaging model (AUC, 0.73; 95% CI: 0.66-0.81; P = .02) and the fusion model (AUC, 0.68; 95% CI: 0.60, 0.76; P = .02) underperformed as compared with the IMPACT model (AUC, 0.83; 95% CI: 0.77, 0.89) in the prediction of unfavorable outcomes. The fusion model outperformed the predictions of the neurosurgeons. Conclusion A deep learning model of head CT and clinical information can be used to predict 6-month outcomes after severe traumatic brain injury. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Haller in this issue.

Presenting Step-Ladder Expansive Cranioplasty as the Next Step After Decompressive Hemicraniectomy: It Is Different!

Context: Decompressive hemicraniectomy (DC) is the final surgical remedy for refractory raised intracranial pressure (ICP). Even with years of experience and profound refination of technique, the procedure has less rewarding results in traumatic brain injury (TBI). Besides, arrangements for bone flap preservation and the necessity of follow-up surgery in the form of cranioplasty bring in unavoidable monetary and logistic burdens to the patients. Step-ladder expansive cranioplasty was conceptualized as an alternative to achieve adequate intracranial volume expansion to help normalize ICP, with immediate reinstitution of the Monro-Kellie doctrine. It is also expected to prevent cerebral cortical pressure injury to the cortex underlying the craniectomy defect. The evolution of this concept, as worked out on different models, the surgical technique, and our experience with this technique are discussed in this article. Evidence Acquisition: Multiple research projects undertaken by our team to build up the concept and acquire data necessary to plan the surgical procedure have been published over last eight years. This review article attempts to evaluate the existing knowledge and our clinical experience so far. Results: Step-ladder expansive cranioplasty allows an assured centrifugal displacement of the inner table and underlying dural bag at craniotomy site by at least 9 mm, thereby achieving a minimum volume expansion of 120 cc. Both of these parameters can be increased as desired, if considered necessary by the surgeon. Conclusions: Step-ladder expansive cranioplasty offers an alternative that takes the centripetal pressure exerted by the combination of the tensile strength of the scalp and atmospheric pressure off the brain surface while achieving an assured augmentation of intracranial volume that can be optimized on a case-to-case basis, based on our future understanding of the subject. While it can be a single-stage surgery for those satisfied with the cosmesis, a revision cranioplasty (if required) will be easier, cheaper, and cosmetically superior to achieving cover over a craniotomy defect routinely done after DC.

Post Traumatic Hydrocephalus: Incidence, Pathophysiology and Outcomes

Background

Post-traumatic hydrocephalus (PTH) is a sequel of traumatic brain injury (TBI) that is seen more often in patients undergoing decompressive craniectomy (DC). It is associated with prolonged hospital stay and unfavorable outcomes.

Objective

To study the incidence and risk factors for development of PTH in patients undergoing DC in our institution and to review the literature on PTH with respect to incidence, risk factors, pathophysiology, and outcomes of management.

Methods

Data from 95 patients (among 220 patients who underwent DC for TBI and fulfilled the inclusion criteria) over a 5-year period at Christian Medical College, Vellore were collected and analyzed to study the incidence and possible risk factors for development of PTH. A review of the literature on PTH was performed by searching PUBMED resources.

Results

Thirty (31.6%) out of 95 patients developed post-traumatic ventriculomegaly, of whom seven (7.3%) developed symptomatic PTH, necessitating placement of ventriculoperitoneal shunt (VPS). No risk factor for development of PTH could be identified. The reported incidence of PTH in the literature is from 0.07% to 29%, with patients undergoing DC having a higher incidence. Younger age, subarachnoid hemorrhage, severity of TBI, presence of subdural hygroma, and delayed cranioplasty after DC are the main risk factors reported in the literature.

Conclusions

PTH occurs in a significant proportion of patients with TBI and can lead to unfavorable outcomes. PTH has to be distinguished from asymptomatic ventriculomegaly as early as possible so that a CSF diversion procedure can be planned early during development of PTH.

Hydrocephalus and Cerebrospinal Fluid Analysis Following Severe Traumatic Brain Injury: Evaluation of a Prospective Cohort

The development of hydrocephalus after severe traumatic brain injury (TBI) is an under-recognized healthcare phenomenon and can increase morbidity. The current study aims to characterize post-traumatic hydrocephalus (PTH) in a large cohort. Patients were prospectively enrolled age 16-80 years old with Glasgow Coma Scale (GCS) score ≤8. Demographics, GCS, Injury Severity Score (ISS), surgery, and cerebrospinal fluid (CSF) were analyzed. Outcomes were shunt failure and Glasgow Outcome Scale (GOS) at 6 and 12-months. Statistical significance was assessed at p < 0.05. In 402 patients, mean age was 38.0 ± 16.7 years and 315 (78.4%) were male. Forty (10.0%) patients developed PTH, with predominant injuries being subdural hemorrhage (36.4%) and diffuse axonal injury (36.4%). Decompressive hemicraniectomy (DHC) was associated with hydrocephalus (OR 3.62, 95% CI (1.62-8.07), p < 0.01). Eighteen (4.5%) patients had shunt failure and proximal obstruction was most common. Differences in baseline CSF cell count were associated with increased shunt failure. PTH was not associated with worse outcomes at 6 (p = 0.55) or 12 (p = 0.47) months. Hydrocephalus is a frequent sequela in 10.0% of patients, particularly after DHC. Shunt placement and revision procedures are common after severe TBI, within the first 4 months of injury and necessitates early recognition by the clinician.

Scoping review of the risk factors and time frame for development of post-traumatic hydrocephalus

Post-traumatic hydrocephalus (PTH) following traumatic brain injury (TBI) may develop within or beyond the acute phase of recovery. Recognition and subsequent treatment of this condition leads to improved neurologic outcomes. In this scoping review, we identify statistically significant demographic, clinical, radiographic, and surgical risk factors as well as a predictive time frame for the onset of PTH in order to facilitate timely diagnosis. Two researchers independently performed a scoping review of the PubMed and Cochrane databases for articles relevant to risk factors for PTH. Articles that met inclusion and exclusion criteria underwent qualitative analysis. Twenty-seven articles were reviewed for statistically significant risk factors and a proposed time frame for the onset of PTH. Variables that could serve as proxies for severe brain injuries were identified as risk factors. The most commonly identified risk factors included either very young or old age, intracranial hemorrhage including intraventricular hemorrhage, hygroma, and need for decompressive craniectomy. Although the timeframe for diagnosis of PTH varied widely from within one week to 31.5 months after injury, the first 50 days were more likely. Established risk factors and timeframe for PTH development may assist clinicians in the early diagnosis of PTH after TBI. Increased consistency in diagnostic criterion and reporting of PTH may improve recognition with early treatment of this condition in order to improve outcomes.

Incidence of post-traumatic hydrocephalus in traumatic brain injury patients that underwent DC versus those that were managed without DC: A systematic review and meta-analysis

Introduction

There is an ongoing debate whether Decompressive Craniectomy (DC) serves as an independent risk factor for the development of Post-traumatic Hydrocephalus (PTH).

Research question

The aim of this systematic review and meta-analysis was to compare the incidence of PTH in TBI patients that underwent DC versus those that were managed without DC.

Materials and methods

The literature was systematically reviewed to identify studies with specific inclusion criteria: (1) Randomized Controlled Trials and observational studies with more than 10 patients in each study arm, (2) comparing the incidence of PTH, (3) in patients aged ≥15 years old, (4) that either underwent DC or received other treatment (non-DC). (5) Only studies in English were included and (6) no restrictions were applied on publication date. The pooled Odds Ratio (OR) and Confidence Interval (CI) were calculated. The quality of the included studies was assessed using the ROBINS and RoB 2.0 tools.

Results

Evidence from six articles was synthesized, incorporating data from 2522 patients. A statistically significant higher occurrence of PTH [OR (95% CI): 4.84 (2.51, 9.31); Pz ​< ​0.00001] was identified in patients undergoing DC for TBI when compared to those that were managed without DC. The same was true when only patients with severe TBI were included in the analysis [OR (95% CI): 2.87 (1.85, 4.43); Pz ​< ​0.00001].

Discussion and conclusion

Our study has shown, within limitations, a clear association between DC and PTH. Further prospective studies, providing high-quality evidence, are needed to definitively establish any causative relationship between DC and PTH.

•

TBIs are associated with the development of PTH.

•

Patients undergoing decompressive craniectomy are more likely to develop PTH.

•

Further studies should be conducted to establish a causative relationship.