Treatment of CSF leakage and infections of dural substitute in decompressive craniectomy using fascia lata implants and related anatomopathological findings

A robust and biodegradable hydroxyapatite/poly(lactide-co-ε-caprolactone) electrospun membrane for dura repair

Typically occurring after trauma or neurosurgery treatments, dura mater defect and the ensuing cerebrospinal fluid (CSF) leakage could lead to a number of serious complications and even patient's death. Although numerous natural and synthetic dura mater substitutes have been reported, none of them have been able to fulfill the essential properties, such as anti-adhesion, leakage blockage, and pro-dura rebuilding. In this study, we devised and prepared a series of robust and biodegradable hydroxyapatite/poly(lactide-co-ε-caprolactone) (nHA/PLCL) membranes for dura repair via an electrospinning technique. In particular, PLLA/PCL (80/20) was selected for electrospinning due to its mechanical properties that most closely resembled natural dural tissue. Studies by SEM, XRD, water contact angle and in vitro degradation showed that the introduction of nHA would destroy PLCL's crystalline structure, which would further affect the mechanical properties of the nHA/PLCL membranes. When the amount of nHA added increased, so did the wettability and in vitro degradation rate, which accelerated the release of nHA. In addition, the high biocompatibility of nHA/PLCL membranes was demonstrated by in vitro cytotoxicity data. The in vivo rabbit dura repair model results showed that nHA/PLCL membranes provided a strong physical barrier to stop tissue adhesion at dura defects. Meanwhile, the nHA/PLCL and commercial group's CSF had a significantly lower number of inflammatory cells than the control groups, validating the nHA/PLCL's ability to effectively lower the risk of intracranial infection. Findings from H&E and Masson-trichrome staining verified that the nHA/PLCL electrospun membrane was more favorable for fostering dural defect repair and skull regeneration. Moreover, the relative molecular weight of PLCL declined dramatically after 3 months of implantation, according to the results of the in vivo degradation test, but it retained the fiber network structure and promoted tissue growth, demonstrating the good stability of the nHA/PLCL membranes. Collectively, the nHA/PLCL electrospun membrane presents itself as a viable option for dura repair.

Brain abscess - A rare confounding factor for diagnosis of post-traumatic epilepsy after lateral fluid-percussion injury

OBJECTIVE

To assess the prevalence of brain abscesses as a confounding factor for the diagnosis of post-traumatic epilepsy (PTE) in a rat model of lateral fluid-percussion-induced (FPI) traumatic brain injury (TBI).

METHODS

This retrospective study included 583 rats from 3 study cohorts collected over 2009-2022 in a single laboratory. The rats had undergone sham-operation or TBI using lateral FPI. Rats were implanted with epidural and/or intracerebral electrodes for electroencephalogram recordings. Brains were processed for histology to screen for abscess(es). In abscess cases, (a) unfolded cortical maps were constructed to assess the cortical location and area of the abscess, (b) the abscess tissue was Gram stained to determine the presence of gram-positive and gram-negative bacteria, and (c) immunostaining was performed to detect infiltrating neutrophils, T-lymphocytes, and glial cells as tissue biomarkers of inflammation. In vivo and/or ex vivo magnetic resonance images available from a subcohort of animals were reviewed to evaluate the presence of abscesses. Plasma samples available from a subcohort of rats were used for enzyme-linked immunosorbent assays to determine the levels of lipopolysaccharide (LPS) as a circulating biomarker for gram-negative bacteria.

RESULTS

Brain abscesses were detected in 2.6% (15/583) of the rats (6 sham, 9 TBI). In histology, brain abscesses were characterized as vascularized encapsulated lesions filled with neutrophils and surrounded by microglia/macrophages and astrocytes. The abscesses were mainly located under the screw electrodes, support screws, or craniectomy. Epilepsy was diagnosed in 60% (9/15) of rats with an abscess (4 sham, 5 TBI). Of these, 67% (6/9) had seizure clusters. The average seizure frequency in abscess cases was 0.436 ± 0.281 seizures/d. Plasma LPS levels were comparable between rats with and without abscesses (p > 0.05).

SIGNIFICANCE

Although rare, a brain abscess is a potential confounding factor for epilepsy diagnosis in animal models of structural epilepsies following brain surgery and electrode implantation, particularly if seizures occur in sham-operated experimental controls and/or in clusters.

Dural Reconstruction Materials for the Repairing of Spinal Neoplastic Cerebrospinal Fluid Leaks

Spinal tumors often lead to more complex complications than other bone tumors. Nerve injuries, dura mater defect, and subsequent cerebrospinal fluid (CSF) leakage generally appear in spinal tumor surgeries and are followed by serious adverse outcomes such as infections and even death. The use of suitable dura mater replacements to achieve multifunctionality in fluid leakage plugging, preventing adhesions, and dural reconstruction is a promising therapeutic approach. Although there have been innovative endeavors to manage dura mater defects, only a handful of materials have realized the targeted multifunctionality. Here, we review recent advances in dura repair materials and techniques and discuss the relative merits in both preclinical and clinical trials as well as future therapeutic options. With these advances, spinal tumor patients with dura mater defects may be able to benefit from novel treatments.

Autologous Free Fascia Lata Can Be Used as Dura Graft in the Salvage Treatment of Recalcitrant Postcraniotomy Intracranial Infection Caused by Multidrug-Resistant Gram-Negative Bacteria

Objective

The multidrug-resistant (MDR) gram-negative bacteria-induced intracranial infections after neurosurgical procedures represent a particular therapeutic challenge. Combining the removal of infected prosthetic meninge plus an appropriate antibiotic administration appears to be the only therapeutic strategy likely to succeed when the infection is complicated by artificial dura mater. This study aimed to assess the efficacy of free fascia lata as a substitute for dura reconstruction in the salvage treatment for such recalcitrant nosocomial infections.

Methods

The retrospective, observational study was conducted at Shanghai Tenth hospital. Patients with definite intracranial infection caused by MDR Gram-Negative bacteria who underwent salvage dura reconstruction using autologous free fascia lata were included in the study. Electronic medical data on clinical characteristics, underlying condition, bacterial culture, antibiotic susceptibilities, perioperative management, surgical techniques, outcome, and follow-up were collected and analyzed.

Results

19 patients were included in the study cohort. All these patients underwent salvage surgery, including removal of infected artificial dura substitute, achievement of complete dura seal with free fascia lata, and other adjunctive procedures to drain the CSF and infuse sensitive antimicrobial agents. Intraventricular or intrathecal administration of antibiotics, including Colistin (14 case), Tigecycline (1 case), Amikacin (1 case), was employed in 16 patients. The infection was cured in 17 patients. In-hospital death occurred in 3 patients. One died from multiple system/organ failure, 1 died from massive occipital ICH, 1 died from brain stem hemorrhage after ventricular-peritoneal shunt surgery. The patients remained without clinical evidence of recurrence during the follow-up period.

Conclusion

On the basis of a comprehensive approach to achieving prompt sterilization of causative pathogens and an optimal healing environment, free fascia lata can serve as a simpler but effective option for dura reconstruction even in the setting of a severe septic area for patients who otherwise need much more complicated and demanding tissue transfer surgery.

Mussel-inspired bioactive 3D-printable poly(styrene-butadiene-styrene) and the in vitro assessment for its potential as cranioplasty implants

Challenges of cranial defect reconstruction after craniotomy arise from insufficient osteogenesis and biofilm infection, which requires novel biomaterials. Herein, we proposed a mussel-inspired bioactive poly(styrene-butadiene-styrene) (SBS) as a promising cranioplasty...

Single-arm, open-label, multicentre first in human study to evaluate the safety and performance of dural sealant patch in reducing CSF leakage following elective cranial surgery: the ENCASE trial

OBJECTIVE

The dural sealant patch (DSP) is designed for watertight dural closure after cranial surgery. The goal of this study is to assess, for the first time, safety and performance of the DSP as a means of reducing cerebrospinal fluid (CSF) leakage in patients undergoing elective cranial intradural surgery with a dural closure procedure.

DESIGN

First in human, open-label, single-arm, multicentre study with 360-day (12 months) follow-up.

SETTING

Three large tertiary reference neurosurgical centres, two in the Netherlands and one in Switzerland.

PARTICIPANTS

Forty patients undergoing elective cranial neurosurgical procedures, stratified into 34 supratentorial and six infratentorial trepanations.

INTERVENTION

Each patient received one DSP after cranial surgery and closure of the dura mater with sutures.

OUTCOME MEASURES

Primary composite endpoint was occurrence of one of the following events: postoperative percutaneous CSF leakage, intraoperative leakage at 20 cm H₂O positive end-expiratory pressure or postoperative wound infection. Overall success was defined as achieving the primary endpoint in no more than two patients. Secondary endpoints were device-related serious adverse events or adverse events (AEs), pseudomeningocele and thickness of dura+DSP. Additional endpoints were reoperation in 30 days and user satisfaction.

RESULTS

No patients met the primary endpoint. No device-related (serious) AEs were observed. There were two incidences of self-limiting pseudomeningocele as confirmed on MRI. Thickness of dura and DSP were (mean±SD) 3.5 mm±2.0 at day 7 and 2.1 mm±1.2 at day 90. No patients were reoperated within 30 days. Users reported a satisfactory design and intuitive application.

CONCLUSIONS

DSP, later officially named Liqoseal, is a safe and potentially efficacious device for reducing CSF leakage after intracranial surgery, with favourable clinical handling characteristics. A randomised controlled trial is needed to assess Liqoseal efficacy against the best current practice for reducing postoperative CSF leakage.

TRIAL REGISTRATION NUMBER

NCT03566602.

The Effect of Adding Modified Chitosan on the Strength Properties of Bacterial Cellulose for Clinical Applications

Currently, several materials for the closure of the dura mater (DM) defects are known. However, the long-term results of their usage reveal a number of disadvantages. The use of antibiotics and chitosan is one of the major trends in solving the problems associated with infectious after-operational complications. This work compares the mechanical properties of samples of bacterial nanocellulose (BNC) impregnated with Novochizol™ and vancomycin with native BNC and preserved and native human DM. An assessment of the possibility of controling the mechanical properties of these materials by changing their thickness has been performed by statistical analysis methods. A total of 80 specimens of comparable samples were investigated. During the analysis, the results obtained, the factor of Novochizol™ addition has provided a statistically significant impact on the strength properties (Fisher Criteria p-value 0.00509 for stress and 0.00112 for deformation). Moreover, a stronger relationship between the thickness of the samples and their ultimate load was shown: R2=0.236 for BNC + Novochizol™ + vancomycin, compared to R2=0.0405 for native BNC. Using factor analysis, it was possible to show a significant effect of modified chitosan (Novochizol™) on the ultimate stress (p-value = 0.005).

Applications of materials for dural reconstruction in pre-clinical and clinical studies: Advantages and drawbacks, efficacy, and selections

The dura mater provides a barrier to protect the tissue underneath and cerebrospinal fluid. However, dural defects normally cause cerebrospinal fluid leakage and other complications, such as wound infections, meningitis, etc. Therefore, the reconstruction of dura mater has important clinical significance. Current dural reconstruction materials include: homologous, acellular, natural, synthetic, and composite materials. This review comprehensively summarizes the characteristics and efficacy of these dural substitutes, especially in clinical applications, including the advantages and drawbacks of those from different sources, the host tissue response in pre-clinical studies and clinical practice, and the comparison of these materials across different surgical procedures. Furthermore, the selections of materials for different surgical procedures are highlighted. Finally, the challenges and future perspectives in the development of ideal dural repair materials are discussed.