Evaluation of the healing process after dural reconstruction achieved using a free fascial graft

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.

Effectiveness of Repair Techniques for Spinal Dural Tears: A Systematic Review

BACKGROUND

Incidental or intentional durotomy in spine surgery is associated with a risk of cerebrospinal fluid (CSF) leakage and reoperation. Several strategies have been introduced, but the incomplete closure is still relatively frequent and troublesome. In this study, we review current evidence on spinal dural repair strategies and evaluate their efficacy.

METHODS

PubMed, Web of Science, and Scopus were used to search primary studies about the repair of the spinal dura with different techniques. Of 265 articles found, 11 studies, which specified repair techniques and postoperative outcomes, were included for qualitative and quantitative analysis. The primary outcomes were CSF leakage and postoperative infection.

RESULTS

The outcomes of different dural repair techniques were available in 776 cases. Pooled analysis of 11 studies demonstrated that the most commonly used technique was a combination of primary closure, patch or graft, and sealant (22.7%, 176/776). A combination of primary closure and patch or graft resulted in the lowest rate of CSF leakage (5.5%, 7/128). In this study, sealants as an adjunct to primary closure (13.7%, 18/131) did not significantly reduce the rate of CSF leakage compared with primary closure alone (17.6%, 18/102). The rates of infection and postoperative neurologic deficit were similar regardless of the repair techniques.

CONCLUSIONS

Although the use of sealants has become prevalent, available sealants as an adjunct to primary closure did not reduce the rate of CSF leakage compared with primary closure. The combination of primary closure and patches or grafts could be effective in decreasing postoperative CSF leakage.

In vivo Evaluation of Fibrous Collagen Dura Substitutes

Dura substitutes are applied in duraplasty to repair lost or damaged dura. Collagen-based dura substitutes are mainstream products in both the US and Chinese markets. In this study, dura substitute devices with potential dura regeneration ability are evaluated. The dura substitutes are composed of fibrous type I collagen that were purified from bovine tendon. Physical and chemical characterization demonstrated that the tested dura substitute has desirable porous scaffolding structures and is composed of highly purified type I collagen. The collagen dura substitutes were further investigated in vivo with a rabbit model for 6 months to evaluate their safety and performance to repair and regenerate dura. No inflammation or infection was observed during the course of in vivo study. The integration of the collagen dura substitutes with surrounding tissue was normal as compared to native tissue. The macroscopic and microscopic histological assessments of the sampled animal tissue showed that the damaged dura were regenerated. The collagen dura substitutes were resorbed between 3 and 6 months along with newly regenerated dura. Both tissue adhesion and dura repair was the worst in blank control group as compared to those in the collagen dura substitutes. Taken together, regenerative collagen dura substitutes demonstrated with suitable physicochemical properties. The in vivo evaluation in a rabbit model further demonstrated the safety and performance of such substitutes for dura repair and regeneration.

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.

Extradural Contralateral C7 Nerve Root Transfer in a Cervical Posterior Approach for Treating Spastic Limb Paralysis: A Cadaver Feasibility Study

STUDY DESIGN

Anatomic study in nine fresh-frozen cadavers.

OBJECTIVE

To confirm the anatomical feasibility of transferring the extradural ventral roots (VRs) and dorsal roots (DRs) of contralateral C7 nerves to those of the ipsilateral C7 nerves respectively through a cervical posterior approach.

SUMMARY OF BACKGROUND DATA

The contralateral C7 nerve root transfer technique makes breakthrough for treating spastic limb paralysis. However, its limitations include large surgical trauma and limited indications.

METHODS

Nine fresh-frozen cadavers (four females and five males) were placed prone, and the feasibility of exposing the bilateral extradural C7 nerve roots, separation of the extradural C7 VR and DR, and transfer of the VR and DR of the contralateral C7 to those of the ipsilateral C7 on the dural mater were assessed. The pertinent distances and the myelography results of each specimen were analyzed. The acetylcholinesterase (AChE) and antineurofilament 200 (NF200) double immunofluorescent staining were preformed to determine the nerve fiber properties.

RESULTS

A cervical posterior midline approach was made and the laminectomy was performed to expose the bilateral extradural C7 nerve roots. After the extradural C7 VR and DR are separated, the VR and DR of the contralateral C7 have sufficient lengths to be transferred to those of the ipsilateral C7 on the dural mater. The myelography results showed that the spinal cord is not compressed after the nerve anastomosis. The AChE and NF200 double immunofluorescent staining showed the distal ends of the contralateral C7 VRs were mostly motor nerve fibers, and the distal ends of the contralateral C7 DRs were mostly sensory nerve fibers.

CONCLUSION

Extradural contralateral C7 nerve root transfer in a cervical posterior approach for treating spastic limb paralysis is anatomically feasible.

LEVEL OF EVIDENCE

5.

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

PURPOSE

Decompressive craniectomy (DC) is widely used to treat raised intracranial pressure (ICP) in cranial trauma and stroke. It is accompanied by numerous complications. The aim of our study is to assess the surgical treatment of infections related to the use of a dural substitute with concurrent CSF leakage performed at our institution.

MATERIAL AND METHODS

A retrospective analysis of a series of 72 patients who underwent DC between 2011 and 2017 was performed. Seven cases (9%) showed infection related to the use of xenograft (bovine pericardium) and coexisting CSF leakage. Epidural/subdural empyemas were observed in seven cases; three in conjunction with an intracerebral abscess. For reconstruction, free anterolateral thigh fascia lata flaps were used, based on the size of the defect.

RESULTS

After removal of the dural substitute and the implant of free fascia lata, infection and CSF leaks resolved in all. An anatomopathological examination of the implant at the later time of cranioplasty (CP) showed the tissue had become vascularized exhibiting integration with the native dura. No complications related to the harvesting of the fascia lata were observed.

CONCLUSIONS

Fascia lata is a validated source of autologous grafts; it is cost-free and would appear to be the biological material most similar to the dura mater. The implanted material appears to maintain a lasting vitality when covered over with a well-vascularized scalp, even after a period of months, achieving a successful suppression of infection. Subsequent skull reconstruction is performed safely and easily using artificial bone.

Sciatic Nerve to Pudendal Nerve Transfer: Anatomical Feasibility for a New Proposed Technique

Aim Restoration of bladder and bowel continence after pudendal nerve anastomosis has been shown successfully in animal models and may be applicable in humans. Aim of this cadaveric study was to assess feasibility of pudendal nerve neurotization using motor fascicles from sciatic nerve.

Methods Pudendal and sciatic nerves were exposed via gluteal approach in 5 human cadavers (10 sites). Size of pudendal and sciatic nerves and the distance between two nerves was measured.

Results There were four male and one female cadavers. Mean age was 62 (range, 50–70) years. Mean pudendal nerve diameter was 2.94 mm (right side) and 2.82 mm (left side). Mean sciatic nerve diameter was 11.2 mm (right side) and 14.2 mm (left side). The distance between two nerves was 23.4 mm on both sides.

Conclusion Transfer of the motor fascicles from sciatic nerve to pudendal nerve to restore the bladder and bowel continence is feasible.

Inflammation by activated macrophage-like THP-1 cells increases human dura mater cell adhesion with alteration of integrin α2 β1 and matrix metalloproteinase

This study was designed to investigate (i) extracellular matrix to specify adhesive substrates to human dura mater cell (hDMC); (ii) the alteration on adhesion-related molecules in hDMC; and (iii) secreted matrix metalloproteinases (MMPs) linked with extracellular matrix remodeling after exposure to inflammation. The hDMC was cultured from human dura mater tissue, and the studies were performed with hDMC after co-culturing with macrophage like THP-1 cells (Mϕ). The adhesion of co-cultured hDMC through collagen I increased 6.4-fold and through collagen IV increased 5.0-fold compared with the adhesion of naïve cells (p < 0.001). Integrin subtype α₂ β₁ expression was increased 6.3-fold (p < 0.001) and α₁ expression was decreased 2.0-fold (p < 0.001) in the co-cultured cells compared with the naïve cells. Co-culturing induced significant increases in MMP-1 (13.9-fold, p < 0.01), MMP-3 (7.6-fold, p < 0.01), and VEGF (VEGF: 3.8-fold, p < 0.05) expression and decreases in MMP-9 (0.1-fold, p < 0.01) compared with the sum of naïve hDMC and Mϕ values. Increased hDMC adhesion under inflammatory conditions is caused by an increased cellular affinity for collagen I and IV mediated by increased hDMC levels of integrin subtype α₂ β₁ and environmental MMP-1, -3 and decreased MMP-9. Selective integrin subtype α₂ β₁ inhibition assay showed 37.8% and 35.7% reduction in adhesion of co-cultured hDMC to collagen I (p < 0.001) and IV (p = 0.057), respectively. The present study provides insight into the pathological conditions related to dura mater adhesion in inflammation. © 2018 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 9999:1-11, 2019.

Anatomical Feasibility of Extradural Transferring S2 and S3 Ventral Roots to S1 Ventral Root for Restoring Neurogenic Bladder in Spinal Cord Injury

STUDY DESIGN

Anatomic study in six formalin-fixed cadavers.

OBJECTIVE

To determine the anatomical feasibility of transferring the S2 and S3 ventral roots (VRs) to S1 VR as a method for restoring bladder dysfunction in spinal cord injury.

SUMMARY OF BACKGROUND DATA

A large quantity of researches of neuroanastomosis methods have been used for treating the bladder dysfunction in spinal cord injury. However, some limitations retard the development of those studies.

METHODS

In this study, six formalin-fixed cadavers (four males, two females) were dissected. The feasibility of exposing the S1, S2, and S3 extradural nerve roots by the limited laminectomy, isolating the VR and dorsal roots from each extradural nerve root and transferring the S2,S3 VRs to the S1 VR were assessed. The pertinent distances and the nerve cross-sectional areas in each specimen were measured. The morphology of each nerve root was observed by hematoxylin-eosin staining.

RESULTS

The limited laminectomy was performed to expose the S1 to S3 extradural nerve roots. The VRs could be isolated from each extradural nerve root at the location of the dorsal root ganglion and the hematoxylin-eosin staining showed that there were some connective tissues separating the VRs from the corresponding dorsal root ganglion. The S2 and S3 VRs have sufficient lengths to be transferred to S1 VR without grafting. The mean cross-sectional area of the S1 VR was 2.60 ± 0.17 mm, and that was 1.02 ± 0.32 mm and 0.51 ± 0.21 mm of the S2 and S3 VRs, respectively.

CONCLUSION

This study demonstrated that use of the S2 and S3 VRs for extradural transfer to S1 VR for restoring bladder dysfunction is surgically feasible.

LEVEL OF EVIDENCE

5.

Cisterna magna arachnoid membrane suturing decreases incidence of pseudomeningocele formation and incisional CSF leakage

OBJECTIVE

A pseudomeningocele and an incisional cerebrospinal fluid leak are considered frequent complications following neurosurgical operations. The rate of these complications especially increases following neurosurgical procedures on the posterior cranial fossae. According to some publications, the rate of pseudomeningoceles has been reported as high as 40%, whereas that of incisional cerebrospinal fluid leaks is up to 17%. For the purposes of reducing the risk of these complications after a midline suboccipital craniotomy, we propose suturing the arachnoid membrane of the cisterna magna. In this paper, we present a retrospective analysis of arachnoid membrane suturing.

METHODS

Seventy patients underwent midline suboccipital craniotomy by the first author between 2012 and 2016 at Burdenko Neurosurgery Institute. In this group was included a consecutive group of patients with posterior fossae tumors where the approach was performed through the cisterna magna arachnoid membrane following midline suboccipital craniotomy and dural opening. The patients were divided into two groups. Group 1 included 38 patients to whom cisterna magna arachnoid membrane suturing was performed with monofilament nonabsorbable suture 7.0., and additionally, the suture was sealed with fibrin adhesive sealant TachoComb®. Group 2 included 32 patients without arachnoid membrane suturing. There was no other significant difference in terms of clinical signs and surgical procedures between these groups. In the postoperative period, the frequency of developing a pseudomeningocele and an incisional cerebrospinal fluid leak was assessed in these two groups. The results were evaluated on the basis of clinical, CT, and MRI data performed in the postoperative period.

RESULTS

In the patients who underwent arachnoid membrane suturing (group I), pseudomeningocele formation was observed in one (2.6%) and CSF leak in one (2.6%) of the 38 patients. In group II, in which patients had no arachnoid membrane suturing, we observed pseudomeningocele formation in 11 (34.4%) patients and a CSF leak in 7 (25.0%) out of 28 patients with known follow-up. Statistical analysis of the data indicates a significantly higher risk of postoperative pseudomeningocele formation and/or an incisional cerebrospinal fluid leak in a group of patients who did not undergo arachnoid membrane suturing (p < 0.05).

CONCLUSIONS

Suturing of the arachnoid membrane of the cisterna magna and its further sealing with fibrin adhesive sealant TachoComb® create an additional barrier for preventing cerebrospinal fluid collection in the extradural space. This technique significantly reduces the risk of postoperative pseudomeningocele formation and/or an incisional cerebrospinal fluid leak in patients with midline suboccipital craniotomy.

Seizure After Cranioplasty: Incidence and Risk Factors

BACKGROUND

To investigate clinical characteristics of postcranioplasty seizures (PCS) first observed after cranioplasty after decompressive craniectomy (DC) to treat traumatic brain injury and to define factors that increase PCS risk.

METHODS

This retrospective study, covering the period between January 2008 and July 2015, compared PCS in postcranioplasty patients. Postcranioplasty seizures risk factors included diabetes mellitus, hypertension, time between DC and cranioplasty, duraplasty material, cranioplasty contusion location, electrocautery method, PCS type, and infection. Multivariate logistic regression analysis was performed and confidence intervals (CIs) were calculated (95% CI).

RESULTS

Of 270 patients, 32 exhibited initial PCS onset postcranioplasty with 11.9% incidence (32/270). Patients fell into immediate (within 24 hours), early (from 1 to 7 days), and late (after 7 days) PCS groups with frequencies of 12, 5, and 15 patients, respectively. Generalized, partial, and mixed seizure types were observed in 13, 13, and 6 patients, respectively. Multivariate logistic regression analysis showed increased risk with increasing age (>50 years). Cranioplasty contusion location, precranioplasty deficits, duraplasty material, and monopolar electrocautery were predictive of PCS onset (P < 0.05). Increased DC to cranioplasty interval increased risk but was not statistically significant (P = 0.062).

CONCLUSIONS

Understanding risk factors for PCS will benefit the management of cranioplasty patients.

Dural Repair in Cranial Surgery Is Associated with Moderate Rates of Complications with Both Autologous and Nonautologous Dural Substitutes

OBJECTIVE

Duraplasty, a common neurosurgical intervention, involves synthetic or biological graft placement to ensure dural closure. The objective of this study is to advance our understanding of the use of dural substitutes in cranial surgery.

METHODS

The PubMed database was systematically searched to identify studies published over the past decade (2007-2017) that described duraplasty procedures. Clinical data were disaggregated and analyzed for the comparisons of biological versus synthetic grafts.

RESULTS

A total of 462 cases were included in the quantitative synthesis. Overall, the most common indication for duraplasty was tumor resection (53%). Allografts were more frequently used in decompression for Chiari malformations compared with xenografts and synthetic grafts (P < 0.001). Xenografts were more frequently used in decompressive hemicraniectomy procedures for evacuation of acute subdural hematomas over allografts and synthetics (P < 0.001). Synthetic grafts were more frequently used in tumor cases than biological grafts (P = 0.002). The cumulative complication rate for dural substitutes of all types was 11%. There were no significant differences in complication rates among the 3 types of dural substitutes.

CONCLUSIONS

Dural substitutes are commonly used to ensure dural closure in a variety of cranial procedures. This study provides greater insight into duraplasty practices and highlights the moderate complication rate associated with the procedure. Future studies are needed to determine the safety and efficacy of such procedures in larger prospective cohorts.

Use of Costal Perichondrium as an Interpositional Graft for Septal Perforation Closure

Importance

Closure of septal perforations remains a technically difficult procedure to perform.

Objective

To assess the use of costal perichondrium as an interpositional graft to enhance closure of septal perforations using bilateral mucosal flaps and the effectiveness of the procedure.

Design, Setting, and Participants

This case series included all 51 consecutive patients presenting with septal perforations from January 1, 2006, to August 31, 2014, at a single institution. Mean (SD) follow-up was 19 (18) months. Patients with subtotal perforations did not have their perforations closed but underwent rhinoplasty with improved form and function. All patients underwent evaluation for changes in postoperative symptoms.

Interventions

Bipedicled mucoperichondrial flaps with placement of costal perichondrium between the repaired flaps.

Main Outcomes and Measures

Success rate of septal perforation closures and the clinical impact of the success of closure as experienced by the patient using the validated Nasal Obstruction Symptom Evaluation (NOSE) questionnaire (range, 0-20; higher scores indicate greater obstruction).

Results

Of the 51 patients (14 male; 37 female; median age, 42.6 [range, 17-69] years), 44 underwent attempted closure of the perforation at the time of the procedure. Closure was successful in 42 of the 44 patients (95%).Two patients had persistent perforations, one of which was subsequently closed in a secondary procedure. Twenty-six of 51 patients with septal perforations completed preoperative and postoperative NOSE questionnaires. The mean (SD) preoperative and postoperative NOSE scores were 12.6 (4.2; range, 6-20) and 3.4 (3.8; range, 0-12), respectively (P < .001). A mean (SD) improvement of 9.0 (3.9) points in the NOSE score was observed from patients after closure of their septal perforation, and 10 patients reported no symptoms (NOSE score, 0).

Conclusions and Relevance

Costal perichondrium is an effective interpositional graft to be used in conjunction with the bilateral mucoperichondrial flaps for closure of septal perforations. Costal perichondrium may be used to aid in closure rates of septal perforations.

Level of Evidence

4.

The feasibility study of extradural nerve anastomosis technique for canine bladder reinnervation after spinal cord injury

OBJECTIVE

Intradural nerve anastomosis for bladder innervation has been demonstrated to be useful. However, its clinical application remains limited because of the complex surgery, its complications and extensive bony destruction. The purpose of the current study was to demonstrate the feasibility of extradural spinal root anastomosis for bladder innervation in canines.

METHODS

Ten beagle dogs were used. The length of the extradural segment of the nerve root, upper nerve root outlet (the point at which it emerges from the spinal dura mater) to S2 (dS2), the S3 (dS3) nerve root outlet distance, and the diameters of the extradural spinal roots were measured. The numbers of nerve fibers from L6 to S3 ventral roots were calculated using immunohistochemical staining.

RESULTS

The extradural spinal roots could be divided into a ventral root (VR) and a dorsal root (DR) before the ganglionic enlargement of the dorsal root, and the extradural motor nerve roots situate ventrally to their corresponding sensory nerve roots. The extradural nerve root lengths of S1 and parts of L7 were longer than the corresponding dS2. The numbers of nerve and motor nerve fibers, and the diameters of extradural nerve roots, were gradually descending from L6 to S3.

CONCLUSION

The S1 VRs and parts of the L7 VRs can be extradurally anastomosed to the S2 nerves without tension. A nerve graft was needed for extradural anastomosis of L6 VRs and parts of L7 VRs to S2 VRs. This study demonstrated the feasibility of extradural spinal nerve anastomosis for treating neurogenic bladder in canines.

Two alternative dural sealing techniques in posterior fossa surgery: (Polylactide-co-glycolide) self-adhesive resorbable membrane versus polyethylene glycol hydrogel

BACKGROUND

Post-operative cerebrospinal fluid (CSF) leak in posterior fossa surgery remains a significant source of morbidity. TissuePatchDural (TPD), a novel impermeable adhesive membrane, was used to reinforce dural closure. A comparison with one of the most commonly used dural sealing devices, DuraSeal, has been made.

METHODS

A retrospective, single-center study was conducted on 161 patients who underwent elective posterior fossa surgery. On surgeon's opinion, when a primary watertight closure was not possible, they received TPD or DuraSeal to reinforce dural closure.

RESULTS

Out of 161 patients analyzed, 115 were treated with TPD and 46 with DuraSeal. The post-operative leaks related purely to TPD or DuraSeal failure were recognized in 3 (2.6%) and 5 (10.86%) cases, respectively (P = 0.015). The presence of pre- and post-operative risk factors was associated with an increased incidence of CSF leak in both groups. TPD showed a better control in patients without these risk factors (P = 0.08). The incidence of CSF leak in patients who underwent posterior fossa surgery by craniectomy was statistically lower in TPD group compared to DuraSeal group (3.22% vs 17.8%, respectively; P = 0.008).

CONCLUSIONS

TPD seems to be a safe tool for use as an adjunct to standard dural closure in posterior fossa surgery, particularly in patients without pre- or post-oper ative risk factors, in those who did not develop hydrocephalus, and who underwent craniectomy. The CSF leak rate in TPD group was found to be lower or within the range of the more advanced alternative dural closure strategies, including polyethylene glycol (PEG)-based sealant.

Extradural nerve anastomosis technique for bladder reinnervation in spinal cord injury: anatomical feasibility study in human cadavers

STUDY DESIGN

An anatomic study of extradural spinal root in 9 embalmed cadavers.

OBJECTIVE

To ascertain the anatomical parameters of the extradural spinal root and to demonstrate the feasibility of spinal root anastomoses without opening the spinal dura mater.

SUMMARY OF BACKGROUND DATA

Intradural anastomosis of the spinal root has made breakthrough progress in treating neurogenic bladder in spinal cord injury. However, because of the complex surgical procedures and extensive bony destruction, its clinical use is not widely promoted.

METHODS

Nine formalin-fixed cadavers were used. The distance between the nerve root outlet and ganglion center, the neighboring nerve root-outlet distance, and the gross anatomy of the extradural spinal root were measured with a surgical microscope. The number of nerve fibers from the T7 to S4 ventral roots (VRs) was calculated by immunohistochemical staining.

RESULTS

The longest and shortest lengths of the extradural spinal root were observed at the S4 and T7 levels, with average values of 33.29 and 6.06 mm, respectively. The longest distance between the adjacent nerve root outlets was observed at L1-L2 (mean, 29.16 mm), and shortest at S3-S4 (mean, 11.79 mm). After leaving the dural sac, the spinal root descends in the spinal canal until reaching the corresponding intervertebral foramina, and the motor nerve roots still lie ventrally to the sensory nerve roots. The largest and smallest numbers of nerve fibers were observed at the L3 and S4 levels (mean, 9169 and 1356, respectively).

CONCLUSION

The dorsal roots and VRs can both be successfully harvested and identified outside the dural sac. The S1 VR can be anastomosed to the S2 VR extradurally without nerve grafts. For extradural neuroanastomosis of the thoracic VRs to the S2 VR, a nerve graft is required. In addition, there are a sufficient number of nerve fibers for functional bladder recovery at the T7-T12 and S1 levels. This study supports the feasibility of extradural spinal root anastomosis as a modified surgical method for treating neurogenic bladder.

LEVEL OF EVIDENCE

N/A.

Exogenous bFGF or TGFβ1 accelerates healing of reconstructed dura by CO2 laser soldering in minipigs

This study aims to explore the probable mechanism of better result of dural reconstruction by CO2 laser soldering and the effect of exogenous basic fibroblast growth factor (bFGF) or transforming growth factor-beta1(TGFβ1) on wound healing. In part I of the study, ten minipigs were randomized into two equal groups, and the dural defects were reconstructed by conventional fibrin glue (FG) bonding (group I a) or by CO2 laser soldering (group Ib). In part II, 36 minipigs were randomized into three equal groups, and the dural defect was reconstructed by CO2 laser soldering; then exogenous bFGF or TGFβ1 was administered in group IIb and group IIc, respectively, while group IIa served as control group. The dural specimens were harvested at 1st week postoperatively in part I; and at 1st, 2nd, 3rd, and 4th week postoperatively in part II, they were examined for healing condition and subjected to hematoxylin-eosin (HE) staining and immunohistochemical (IHC) staining with antibodies against bFGF and TGFβ1. In part I, group Ib showed higher fibroblast cell density than group Ia (P < 0.05). The optical density (OD) for IHC staining with antibodies against bFGF of group Ib was significantly higher than that of group Ia (P < 0.05), and for IHC staining with antibodies against TGFβ1, group Ib showed positive staining while group Ia was negative. In part II, administering exogenous bFGF or TGFβ1 made a left shift of fibroblast cell number-time curve compared with control group. For specimens' IHC staining with antibodies against bFGF, the OD of group IIb was higher than that of group IIa in the corresponding time. For specimens' IHC staining with antibodies against TGFβ1, the OD of groups IIb and IIc was both higher than that of group IIa (P < 0.05 and P < 0.01, respectively). In conclusion, CO2 laser may trigger fibroblast proliferation through stimulating the secretion of bFGF and TGFβ1. Topically administering exogenous bFGF or TGFβ1 could accelerate the healing of the reconstructed dura by enhancing secretion of bFGF and/or TGFβ1 and promoting the process of fibroblast gathering-degrading.

A comparison between "sandwich" and conventional methods of repairing spinal dura rupture

OBJECTIVE

To study the therapeutic efficacy of the "sandwich" method (medical glue + gelatin sponge + medical glue) of spinal dural repair for preventing cerebrospinal fluid (CSF) leaks during treatment of subdural tumors.

METHODS

Fifty-four patients with spinal subdural tumors treated between April 2007 and June 2011 were retrospectively investigated. The patients were divided into two groups: a conventional group (group A) and a "sandwich" group (group B). The group A patients included 16 males and 7 females with an average tumor course of 11 months (range, 2-34 months). Four of their 23 tumors were in the cervical spine, eight thoracic, and eleven lumbar. The group B patients included 19 males and 12 females with an average tumor course of 12 months (range, 3-36 months). Five of their 31 tumors were in the cervical spines, 10 thoracic, and 16 lumbar. In group A, the dural repairs were performed with interlocking sutures and a gelatin sponge covering the dura; whereas in group B, they were performed with interlocking sutures, painting of medical glue around the dural incision, covering this with a gelatin sponge, and finally covering of the gelatin sponge with medical glue. The total volume of drainage after operation, incidence of CSF leaks, healing of the incision, and recovery of clinical performance were recorded.

RESULTS

Compared to group A patients, group B patients had a significantly smaller total volume of drainage (P < 0.05) on the day of surgery, and the first, second, and third postoperative days. The incidence of CSF leakage in group B was also significantly less than in group A (P < 0.05). Before discharge, three patients in group A developd hydrops, which was successfully treated by aspiration, continuous pressure from sandbags, and the prone position. During the first 3 months of follow-up, five patients developed deep hydrops under their incisions but required no treatment. There were no obvious abnormalities in group B.

CONCLUSION

After removal of subdural spinal tumors by incising the dura mater, or in related spinal surgery, application of the "sandwich" complex to the damaged spinal dura reduces the volume of drainage postoperatively and reduces the incidence of CSF leakage.

Efficacy of a new instrument for dural defect repair in anterior skull base reconstruction: a technical note

BACKGROUND

The anterior skull base is a deep and narrow area, which makes dural repair technically challenging. The goal of this study was to demonstrate the efficacy of a new instrument for anterior skull base dural repair.

METHODS

Ten patients underwent surgery via the transbasal approach, combined with either a transfacial or a transnasal endoscopic resection. The dural repair was performed prior to tumor resection, and the new instrument was used to suture the fascia lata in an underlay fashion. The repaired dural defect was then covered with a pericranial flap.

RESULTS

The follow-up period ranged from 2 to 18 months, with an average follow-up time of 8.7 months. During this period, none of the patients experienced cerebrospinal fluid leakage, meningitis, tension pneumocephalus, abscess formation, or flap necrosis.

CONCLUSIONS

Our findings suggest that the use of this instrument combined with the technique of suturing the fascia lata in an underlay fashion and covering it with a pericranial flap, may be an effective alternative approach to anterior skull base reconstruction.

Pneumocephalus with BiPAP use after transsphenoidal surgery

While the benefits of continuous positive airway pressure (CPAP) or bilevel positive airway pressure (BiPAP) for patients with obstructive sleep apnea are well described, reports in the literature of complications from its use are rare. A patient who received postoperative BiPAP after undergoing transsphenoidal craniopharyngioma resection developed severe pneumocephalus and unplanned intensive care unit admission. Although the pneumocephalus resolved with conservative management over two weeks, we propose caution in the use of CPAP postoperatively in patients undergoing procedures of the head and neck.

Skull base reconstruction using various types of galeal flaps

BACKGROUND

Failure of skull base reconstruction is a life-threatening issue. This study describes surgical techniques utilising various types of galeal flaps and reports on outcome of these procedures for skull base reconstruction.

METHOD

Clinical records of 136 patients (75 men, 61 women; mean age, 50.0 years) who required skull base reconstruction with galeal flaps were reviewed retrospectively. Patients had undergone skull base surgeries with simultaneous reconstruction for benign tumours in 77 patients, malignant tumours in 53, and other lesions in 6. We repaired dural defects using a fascial patch, and covered the skull base defects using various types of galeal flap according to the size and location of the skull base defects. Routine spinal drainage was not used in any patients.

FINDINGS

Reconstruction was performed as planned in all patients. We utilised a galea frontalis flap in 17 patients, temporoparietal galeal flap in 95, temporoparietal galeal flap with calvarial bone in 9, and bipedicled temporoparietal galeal flap in 15. Postoperative complications included scalp wound necrosis in 8 patients (5.9%), transient leakage of cerebrospinal fluid in 3 (2.2%), and intracranial infection in 2 (1.5%). Necrosis of the galeal flaps was not encountered.

CONCLUSIONS

Galea is a well-vascularised tissue with homogenous thickness. Since the galeal layer covers the entire head area, various types of galeal flap can be elevated to cover any size and location of skull base defect.

Reconstruction techniques in skull base surgery

One of the major challenges of cranial base surgery is reconstruction of basal dural defects. Ineffective reconstruction may result in potentially life-threatening complications such as cerebrospinal fluid leak, meningitis, and tension pneumocephalus. Goals of reconstructive procedures are to repair the dural defect and to separate intracranial contents from bacteria-laden secretion of the mouth, nose, and sinus. Different reconstructive techniques have been reported. Multiple factors may influence the surgical choice of reconstructive technique and its outcome. Regional pedicled flap and vascular free flaps represent the best reconstructive options because vascularized tissues promote fast and complete healing. A variety of endoscopic pedicled mucosal flaps within the nasal cavity have also been described. The different reconstruction techniques are described and discussed in terms of indications, advantages, and drawbacks.

Long-term outcome of endonasal endoscopic skull base reconstruction with nasal turbinate graft

OBJECTIVE

To study the long-term outcome of endonasal endoscopic skull base reconstruction with nasal turbinate tissue free graft.

PATIENTS AND METHODS

This study included 55 consecutive patients who underwent endonasal endoscopic skull base reconstruction with nasal turbinate graft and were available for follow-up. They were 30 patients with pituitary adenomas, 20 with cerebrospinal fluid (CSF) rhinorrhea of different etiologies, three with meningoencephalocele, and two with skull base meningiomas. Autologous nasal turbinate tissue materials were used in reconstructing the skull base defect. Clinical follow-up with endoscopic nasal examination was done routinely 1, 3, 6, and 12 months after surgery. Computed tomography and magnetic resonance imaging were performed when indicated. The follow-up period ranged from 6 months to 8 years.

RESULTS

There were no major operative or postoperative complications. Nasal turbinate graft was effective in sealing of intraoperative CSF leak, obliteration of dead space, and anatomic reconstruction of the skull base. There was no evidence of graft migration or inflammatory changes. Starting from 3 months after surgery to the rest of the follow-up period, endonasal endoscopic view of the site of duraplasty showed that: with small skull base defect (less than 5 mm), there was neither dural pulsation nor prolapse; with moderate-sized defect (5 to 10 mm), there was dural pulsation without prolapse; with larger defect (> 10 mm), there was dural pulsation and prolapse. These finding were constant regardless of the etiology of the lesion and the reconstruction material used.

CONCLUSIONS

This long-term study demonstrated the efficacy of nasal turbinate graft in sealing of CSF leak without any delayed complications. Other rigid materials may be considered in reconstruction of large skull base defect (more than 10 mm) to prevent dural prolapse and herniation. For any future endonasal procedure for those patients, who had previous endonasal endoscopic duraplasty, the surgeons should be fully aware of the state of duraplasty (e.g., dural prolapse) to avoid any intraoperative complication (e.g., penetration of the prolapsed dura during nasal packing).

A comprehensive algorithm for anterior skull base reconstruction after oncological resections

OBJECTIVE

To present our method for anterior skull base reconstruction after oncological resections.

METHODS

One hundred nine patients who had undergone 120 anterior skull base resections of tumors (52 malignant [43%], 68 benign [57%]) via the subcranial approach were studied. Limited dural defects were closed primarily or reconstructed using a temporalis fascia. Large anterior skull base defects were reconstructed by a double-layer fascia lata graft. A split calvarial bone graft, posterior frontal sinus wall, or three-dimensional titanium mesh were used when the tumor involved the frontal, nasal, or orbital bones. A temporalis muscle flap was used to cover the orbital socket for cases of eye globe exenteration, and a rectus abdominis free flap was used for subcranial-orbitomaxillary resection. Pericranial flap wrapping of the frontonaso-orbital segment was performed to prevent osteoradionecrosis if perioperative radiotherapy was planned.

RESULTS

The incidence of cerebrospinal fluid (CSF) leak, intracranial infection, and tension pneumocephalus was 5%. Histopathological and immunohistochemical analysis of fascia lata grafts in reoperated patients (n = 7) revealed integration of vascularized fibrous tissue to the graft and local proliferation of a newly formed vascular layer embedding the fascial sheath.

CONCLUSION

A double-layer fascial graft alone was adequate for preventing CSF leak, meningitis, tension pneumocephalus, and brain herniation. We describe a simple and effective method of anterior skull base reconstruction after resections of both malignant and benign tumors.

Results of the Prospective, Randomized, Multicenter Clinical Trial Evaluating a Biosynthesized Cellulose Graft for Repair of Dural Defects

BACKGROUND

After intradural cranial surgery, a dural substitute is often required for dural closure. Although preferred, limitations of autograft include local availability and additional surgical site morbidity. Thus, allografts, xenografts, and synthetics are frequently used.

OBJECTIVE

To report 6-month results of a randomized, controlled trial of a biosynthesized cellulose (BSC) composed duraplasty device compared with commercially available dural replacements.

METHODS

A total of 99 patients (62 BSC; 37 control) were treated on protocol, using a 2:1 (BSC:control) blocked randomization schedule. Physical examinations were performed pre- and postoperatively within 10 days and at 1, 3, and 6 months. Magnetic resonance imaging was performed preoperatively and at 6 months. The primary study endpoint was the absence of pseudomeningocele and extracerebral fluid collection confirmed radiographically and the absence of cerebrospinal fluid fistula at 6 months.

RESULTS

At 6 months, the primary hypothesis, noninferiority of the BSC implant compared with the control group, was confirmed (P = .0206). Overall success was achieved by 96.6% of BSC and 97.1% of control patients. No significant difference was revealed between treatment groups for surgical site infection (P = 1.0000) or wound healing assessment (P ≥ .3685) outcomes, or radiologic endpoints (P ≥ .4061). Device strength and seal quality favored BSC.

CONCLUSION

This randomized, controlled trial establishes BSC as noninferior to commercially available dural replacement devices. BSC offers a hypothetical advantage concerning prion and other infectious agent exposure; superior handling qualities are evident. Longer term data are necessary to identify limitations of BSC and its potential equivalence to the gold standard of pericranium.

Cranial-base repair using endoscopic laser welding

As the scope of transnasal cranial-base surgery expands, reconstruction of the complex residual defects remains a challenge. Laser welding is a novel technology that can be performed endoscopically and offers the potential of producing instantaneous, watertight repairs using a chromophore-doped biologic solder.

Dural augmentation: part I-evaluation of collagen matrix allografts for dural defect after craniotomy

OBJECTIVE

Primary closure of the dura remains difficult in many neurosurgical cases. One option for dural grafting is the collagen sponge, which is available in multiple forms, namely, monolayer collagen and bilayer collagen. Our primary goal was to assess differences in the incidence of postoperative cerebrospinal fluid (CSF) leak, including fistula and pseudomeningocele, and postoperative infection between monolayer collagen and bilayer collagen grafts.

METHODS

A single-center retrospective analysis of 475 consecutive neurosurgical procedures was performed. Primary endpoints were CSF leak and infection, adjusting for the impact of additional nonautologous materials. Multivariate regression analysis was used to identify predictors of postoperative CSF leak and infection.

RESULTS

The overall frequency of postoperative CSF leak was 6.7%. There was no significant difference in the incidence of CSF leak based on the type of collagen sponge (monolayer versus bilayer) used (5.5% versus 7.5%, respectively; P = 0.38). The overall frequency of postoperative infection was 4.2%. There was no significant difference in the incidence of infection between groups (4.9% versus 3.8%; P = 0.54). Bilayer sponges were associated with a significantly lower incidence of CSF leak than monolayer sponges (odds ratio, 0.09; 95% confidence interval, 0.01-0.73).

CONCLUSION

Bilayer collagen sponges are associated with a reduction in postoperative CSF leak, notably in posterior fossa surgery. The need for additional non-native materials is predictive of postoperative CSF leak, along with location and type of procedure. Intrinsic patient characteristics (e.g., age, diabetes, smoking) do not seem to affect the efficacy of collagen sponge dural grafts.

Simplified harvest of autologous pericranium for duraplasty in Chiari malformation Type I. Technical note

The authors describe a method of harvesting autologous pericranium for duraplasty in patients with Chiari malformation Type I (CM-I) that avoids excessive exposure or a second incision. Nonautologous dural grafts have been associated with numerous complications including hemorrhage, bacteria and virus transmission, fatal Creutzfeldt-Jakob disease transmission, foreign body reaction, systemic immune response, excessive scarring, slower healing, premature graft dissolution, and wound dehiscence. Autogenous tissues have the advantage of being nonimmunogenic, nontoxic, readily available, and inexpensive. Pericranium is a preferred substrate because it is flexible, strong, and easily sutured for a watertight closure. Current literature supports the use of autogenous pericranium for dural grafting in CM-I procedures, but has heretofore failed to provide a method of harvest that avoids the complications associated with a larger exposure or second incision. The authors offer a simple alternative technique for using local pericranium in duraplasty for CM-I or other posterior fossa abnormalities.

Long-term endonasal endoscopic review of successful duraplasty after endonasal endoscopic skull base surgery

BACKGROUND

This study was performed to examine the long-term endonasal endoscopic morphological appearance of successful duraplasty after endoscopic skull base surgery for different pathology.

METHODS

This study included 65 patients who underwent endonasal endoscopic surgery for different skull base lesions with successful duraplasty. Forty patients had pituitary adenomas, 25 with macroadenomas and 15 with microadenomas. Twenty patients with cerebrospinal fluid rhinorrhea of different etiologies and three patients with meningoencephalocele were included. There were two patients with skull base meningiomas, 1 with an extensive greater wing meningioma reaching the nasal cavity and the 1 with recurrent olfactory groove meningioma. Different types of autologous materials were used in reconstructing the skull base defect. Clinical follow-up with endoscopic nasal examination was done routinely 1, 3, 6, and 12 months after surgery. CT and MRI were performed when indicated. The follow-up period ranged from 6 months to 8 years.

RESULTS

Starting from 3 months after surgery to the rest of the follow-up period, endonasal endoscopic view of the site of duraplasty showed that with small skull base defect (<5 mm), there was neither dural pulsation nor prolapse. With moderate-size defect (5-10 mm) there was dural pulsation without prolapse. With larger defect (>10 mm) there was dural pulsation and prolapse. These findings were constant regardless of the etiology of the lesion and the reconstruction material used.

CONCLUSION

This long-term study showed that dural pulsation and prolapse at the site of the successful duraplasty is a function of the size of the bony defect and does not depend on the pathology of the lesion or the autologous material used for reconstruction. For any future endonasal procedure for these patients, the surgeons should be fully aware of the state of duraplasty to avoid any complication.

Free flap transfer for the treatment of intractable postcraniotomy subdural empyemas and epidural abscesses

OBJECTIVE

Postcraniotomy subdural empyemas and epidural abscesses are uncommon, potentially lethal, complications of neurosurgery. Patients with these complications may be difficult to manage, and mortality can occur.

METHODS

Between 1997 and 2006, the authors treated eight patients with recalcitrant postcraniotomy subdural empyema and epidural abscess with combinations of myocutaneous free flap transfer. The free flap transfer was intended for patients who could not be cured with conventional surgical debridement and bone flap removal. Patient ages ranged from 15 to 67 years (mean, 41.5 yr). There were six men and two women. Treatment was required for cranial base tumors (n = 3), the result of trauma (n = 2), malignant tumors (n = 2), and cerebral hematoma (n = 1). In six patients (75%), an expanded polytetrafluoroethylene sheet was used as a dural substitute at the original surgery. We used three rectus abdominis myocutaneous flaps and five latissimus dorsi myocutaneous flaps. In six patients (75%), surgery was performed in the chronic stage of infection, and the other two patients were in the acute stage of infection.

RESULTS

Among all the patients, two failures occurred because of flap ischemia, but these were resolved after an additional procedure. However, one of these two patients, in whom surgery was performed at the acute stage of infection, died 4 weeks after the surgery. The postoperative course of the other six patients was uneventful. Isolated microorganisms were methicillin-resistant Staphylococcus aureus (four patients), Pseudomonas aeruginosa (three patients), and methicillin-sensitive Staphylococcus aureus (one patient).

CONCLUSION

Myocutaneous free flap transfer allows sufficient blood circulation and dead space control and is resistant to infection. Therefore, free flap transfer is useful for eliminating intractable empyema and abscess; however, it is important that the procedure be considered in the chronic stage of infection.

Dural substitute with polyglycolic acid mesh and fibrin glue for dural repair: technical note and preliminary results

BACKGROUND

An ideal dural substitute that enables watertight closure, has sufficient strength, and can be absorbed without remnant materials that induce inflammation, adhesion, and infection is not available. The purpose of this study was to evaluate the efficacy of a bioabsorbable polyglycolic acid (PGA) mesh and fibrin glue as a substitute for dural repair.

METHODS

Altogether, 10 patients with noted dural tears during extradural spinal surgery and 20 patients who underwent durotomy for intradural spinal surgery were included in this study. In a series of 20 consecutive cases, dural closure was performed by suture and fibrin glue. In the subsequent 10 consecutive patients, dural closure was performed by suture and fibrin glue with the use of absorbable PGA mesh. The medical records and magnetic resonance imaging (MRI) of the surgical site were retrospectively reviewed to evaluate the presence of a cerebrospinal fluid (CSF) fistula or leakage after the surgery.

RESULTS

A CSF fistula occurred in five patients who underwent dural repair with fibrin glue alone, and postoperative MRI showed CSF leakage in two patients with incidental dural tears after laminectomy for ossification of ligamentum flavum. No CSF fistula was present in patients who underwent dural repair using PGA mesh and fibrin glue, and no adverse effects or complications were encountered postoperatively. Follow-up MRI revealed no evidence of CSF leakage around the reconstructed dura mater.

CONCLUSIONS

The use of PGA mesh and fibrin glue for the repair of dura mater is a useful method of preventing CSF leakage in spinal surgery.

Novel laser tissue-soldering technique for dural reconstruction

OBJECT

The goal of this study was to use a modified version of the CO2 laser-soldering system to develop a simple and reliable technique for the repair of dural defects after excision of brain tumors.

METHODS

The authors used a CO2 fiber optic laser system that they had developed for heating, monitoring, and controlling tissue temperature in situ and in real time, thereby reducing damage to the brain parenchyma. They adapted the system for dural closure by using free fascial grafts in a porcine model. Measures for estimation of reconstruction quality included visual assessment under magnification and direct measurements of adhesive strength and cerebrospinal fluid leak (CSF) pressure. Reliable soldering was achieved in 54 of 57 experiments, providing a 95% success rate. The average peak adhesive strength was 82 +/- 3 mN/cm2. The measured leak pressure of the fascia-dura mater bond was 66 +/- 5 mm Hg. Conventional suturing performed using Prolene stitches resulted in immediate CSF leakage from areas between the stitches and from the area of the needle hole itself.

CONCLUSIONS

Fascia-dura mater soldering using the CO2 laser is feasible and may support CSF pressure up to six times higher than normal intracranial pressure. Findings of this study may provide a basis for the development of new tools for dural reconstruction.

Cosmetic concerns in posterior fossa skull base surgery

Although cosmetic defects produced by posterior fossa surgery may not seem obvious, a poor cosmetic result can overshadow an otherwise successful operation. It is important to approach the operation with knowledge that each phase of a surgical procedure either directly or indirectly influences the eventual cosmetic result. The careful use of anatomic dissection and repair and attempts to reconstitute bony defects to their native contour as well as avoidance of complications all contribute to excellent cosmetic outcomes.

Skull base reconstruction after anterior subcranial tumor resection

Object

The goal of this study was to demonstrate the efficacy of a simple and reliable technique for anterior skull base and craniofacial reconstruction in patients who have undergone excision of tumors via the subcranial approach.

Methods

There were 63 patients who had undergone 71 anterior skull base resections of tumors via the aforementioned approach. Twenty-nine cases (41%) involved malignant tumors and 42 (59%) involved benign tumors. Reconstruction of the anterior skull base was performed by a single team who used double-layer fascial graft. Limited dural defects were reconstructed using the temporalis fascia, whereas large anterior skull base defects were reconstructed using a fascia lata sheath. Reconstruction was achieved without the support of bone graft or titanium mesh and without pericranial, galeal, or free flaps. Pericranial flap wrapping of the frontonasoorbital segment was performed to prevent osteoradionecrosis if postoperative radiotherapy was planned. The incidence of cerebrospinal fluid (CSF) leakage, intracranial infection, and tension pneumocephalus was 5.6%. Histopathological examination of fascia lata grafts obtained in patients who had undergone a second procedure demonstrated integration of vascularized fibrous tissue to the graft, as well as local proliferation of a newly formed vascular layer embedding the fascial sheath.

Conclusions

The use of a double-layer fascial graft alone was adequate for prevention of CSF leakage, meningitis, tension pneumocephalus, and brain herniation. The double-layer fascial flap provided a simple and reliable means for anterior skull base reconstruction after en bloc resection of both malignant and benign tumors.