Cranioplasty Using Polymethylmethacrylate Cement Following Retrosigmoid Craniectomy Decreases the Rate of Cerebrospinal Fluid Leak and Pseudomeningocele

Application value of calcium phosphate cement in complete cranial reconstructions of microvascular decompression craniectomies

OBJECTIVE

To investigate the application value of calcium phosphate cement (CPC) in repairing cranial defects during microvascular decompression (MVD) surgery via the retrosigmoid approach.

METHODS

A retrospective study was carried out on patients who underwent MVD. According to the two different cranial reconstruction methods, patients were divided into a titanium mesh (TM) group and a CPC group. We compared in the two groups the length of postoperative hospital stay, the incidence of postoperative cerebrospinal fluid (CSF) leakage, the number of patients with suspected postoperative intracranial infection who underwent lumbar puncture, the number of patients with a definitive etiologic diagnosis of intracranial infection, and the imaging evaluation of plastic shape satisfaction.

RESULTS

Patients in the CPC group had an average hospital stay of 9.15 ± 2.00 days, shorter than that in the TM group (10.69 ± 2.86 days), P < 0.001. In the TM group, the rate of plasticity satisfaction was 70/89 (78.65%), which was significantly lower than that in the CPC group (60/66, 90.91%), P = 0.040. Among the patients with a definitive etiologic diagnosis of intracranial infection, there were eight cases in the TM group and one case in the CPC group, and the difference was statistically significant, P = 0.049.

CONCLUSIONS

CPC is another viable alternative for complete cranial reconstructions of microvascular decompression craniectomies. The use of CPC does not increase the incidence of postoperative complications, such as CSF leakage and intracranial infection, and can reduce the average length of hospital stay and the incidence of etiologic diagnosis of intracranial infection. Furthermore, the evaluation of the plastic shape is satisfactory.

Clinical Applications of Poly-Methyl-Methacrylate in Neurosurgery: The In Vivo Cranial Bone Reconstruction

Background: Biomaterials and biotechnology are becoming increasingly important fields in modern medicine. For cranial bone defects of various aetiologies, artificial materials, such as poly-methyl-methacrylate, are often used. We report our clinical experience with poly-methyl-methacrylate for a novel in vivo bone defect closure and artificial bone flap development in various neurosurgical operations. Methods: The experimental study included 12 patients at a single centre in 2018. They presented with cranial bone defects after various neurosurgical procedures, including tumour, traumatic brain injury and vascular pathologies. The patients underwent an in vivo bone reconstruction from poly-methyl-methacrylate, which was performed immediately after the tumour removal in the tumour group, whereas the trauma and vascular patients required a second surgery for cranial bone reconstruction due to the bone decompression. The artificial bone flap was modelled in vivo just before the skin closure. Clinical and surgical data were reviewed. Results: All patients had significant bony destruction or unusable bone flap. The tumour group included five patients with meningiomas destruction and the trauma group comprised four patients, all with severe traumatic brain injury. In the vascular group, there were three patients. The average modelling time for the artificial flap modelling was approximately 10 min. The convenient location of the bone defect enabled a relatively straightforward and fast reconstruction procedure. No deformations of flaps or other complications were encountered, except in one patient, who suffered a postoperative infection. Conclusions: Poly-methyl-methacrylate can be used as a suitable material to deliver good cranioplasty cosmesis. It offers an optimal dural covering and brain protection and allows fast intraoperative reconstruction with excellent cosmetic effect during the one-stage procedure. The observations of our study support the use of poly-methyl-methacrylate for the ad hoc reconstruction of cranial bone defects.

Bone Cement Cranioplasty Reduces Cerebrospinal Fluid Leak Rate after Microvascular Decompression: A Single-Institutional Experience

Background  Microvascular decompression (MVD) is a common surgical treatment for cranial nerve compression, though cerebrospinal fluid (CSF) leak is a known complication of this procedure. Bone cement cranioplasty may reduce rates of CSF leak. Objective  To compare rates of CSF leak before and after implementation of bone cement cranioplasty for the reconstruction of cranial defects after MVD. Methods  Retrospective chart review was performed of patients who underwent MVD through retrosigmoid craniectomy for cranial nerve compression at a single institution from 1998 to 2017. Study variables included patient demographics, medical history, type of closure, and postoperative complications such as CSF leak, meningitis, lumbar drain placement, and ventriculoperitoneal shunt insertion. Cement and noncement closure groups were compared, and predictors of CSF leak were assessed using a multivariate logistic regression model. Results  A total of 547 patients treated by 10 neurosurgeons were followed up for more than 20 years, of whom 288 (52.7%) received cement cranioplasty and 259 (47.3%) did not. Baseline comorbidities were not significantly different between groups. CSF leak rate was significantly lower in the cement group than in the noncement group (4.5 vs. 14.3%; p  < 0.001). This was associated with significantly fewer patients developing postoperative meningitis (0.7 vs. 5.2%; p  = 0.003). Multiple logistic regression model demonstrated noncement closure as the only independent predictor of CSF leak (odds ratio: 3.55; 95% CI: 1.78-7.06; p  < 0.001). Conclusion  CSF leak is a well-known complication after MVD. Bone cement cranioplasty significantly reduces the incidence of postoperative CSF leak and other complications. Modifiable risk factors such as body mass index were not associated with the development of CSF leak.

Bone Cement Internal Auditory Canal Reconstruction to Reduce CSF Leak After Vestibular Schwannoma Retrosigmoid Approach

OBJECTIVE

To describe rates of cerebrospinal fluid (CSF) rhinorrhea after reconstruction of the IAC with calcium phosphate bone cement during retrosigmoid resections of vestibular schwannomas.

METHODS

A retrospective chart review of 177 patients who underwent retrosigmoid craniotomy and opening of the internal auditory canal for resection of a vestibular schwannoma between January 2016 and September 2019 at a tertiary referral center. Patients with other cerebellopontine angle tumor histology, neurofibromatosis type II, or those undergoing revision surgeries were excluded.

RESULTS

Out of 177 patients, six patients (3.4%) developed postoperative rhinorrhea. Four patients (2.3%) were taken back to the OR for mastoidectomy and repair of CSF leak. Three of these patients were noted to have a CSF leak from the peri-labyrinthine air cells, and one was found to have a leak from the craniotomy site communicating with the mastoid air cells. Two patients were conservatively managed with diuretics and had resolution of their CSF leak. Six patients (3.4%) were readmitted for postoperative infection. Two patients were diagnosed with meningitis (1.1%), one aseptic and one H. Influenza, and three patients developed surgical site infections (1.6%). One patient was empirically treated with antibiotics and ultimately had a negative CSF culture.

CONCLUSIONS

Our results demonstrate that the use of calcium phosphate bone cement for IAC closure in retrosigmoid resection of vestibular schwannomas is a safe and effective technique with low rates of postoperative CSF rhinorrhea.

The Vascularized Occipital Fascial Flap (OFF): A Novel Reconstructive Technique for Posterior Fossa Surgery

BACKGROUND

Posterior fossa surgery is particularly prone to cerebrospinal fluid (CSF) leakage. Several methods have been introduced to address and/or prevent this complication. However, to the best of our knowledge, the use of a vascularized fascial flap based on the occipital artery for the purpose of reconstruction has not been reported. We introduce the occipital fascial flap (OFF) for reconstruction of a craniectomy defect after the retrosigmoid approach.

METHODS

A 57-year-old woman with a large cerebellar metastasis underwent gross total resection of the mass followed by reconstruction of the craniectomy defect using OFF.

RESULTS

Postoperative imaging showed flap viability and no CSF leak occurred during follow-up.

CONCLUSIONS

We report the first use of OFF for reconstruction of a craniectomy defect in a retrosigmoid approach. The vascularized fascial flap in posterior fossa surgery is a potentially helpful technique to reduce the risk of CSF leak in high-risk patients.

Factors associated with cerebrospinal fluid leak after a retrosigmoid approach for cerebellopontine angle surgery

Background

The retrosigmoid approach represents a crucial surgical route to address different lesions in the cerebellopontine angle but cerebrospinal fluid (CSF) leak still remains the most frequent complication after this approach. Here, we analyzed the impact of different factors in CSF leak development after a retrosigmoid approach. Identifying risk factors related to a specific approach may help the surgeon to tailor the perioperative management and to appropriately counsel patients regarding their risk profile.

Methods

We retrospectively reviewed the clinical, surgical, and outcome data of 103 consecutive patients (M/F, 47/56; mean follow-up 35.6 ± 23.9 months) who underwent a retrosigmoid approach for different cerebellopontine angle pathologies and studied the impact of different factors on the occurrence of a CSF leak to univariate and multivariate analysis.

Results

Seventy-nine patients (76.7%) were operated for tumors growing in the cerebellopontine angle. Twenty-four patients (23.2%) underwent microvascular decompression to treat a drug-resistant trigeminal neuralgia. Sixteen patients (15.5%) developed CSF leak in the postoperative course of which six underwent surgical revision. Performing a craniectomy as surgical procedure (P = 0.0450) and performing a reopening procedure (second surgery; P = 0.0079) were significantly associated to a higher risk of developing CSF leak. Moreover, performing a reopening procedure emerged as an independent factor for CSF developing on multivariate analysis (P = 0.0156).

Conclusion

Patients submitted to craniectomy and patients who underwent a second surgery showed an higher CSF leak rate. Ongoing improvement of biomaterial technology may help neurosurgeons to prevent this potentially life-threatening complication.

Surgical Nuances to Reduce and Manage Cerebrospinal Fluid Leaks after Microvascular Decompression

Background: No dural substitute has proven to be complication-free in a large clinical trial, even suggesting some benefit during watertight closure. However, primary dural closure is not always possible due to dural shrinkage from electrocautery for dural bleeding. Objective: This study is performed to analyze the clinical outcomes related to cerebrospinal fluid (CSF) leakage after microvascular decompression (MVD) using a simple surgical technique. Methods: Three hundred and sixty consecutive cases were treated with MVD and followed up for more than one month after surgery. Bleeding from the cut veins during dural incision was controlled by pulling stay sutures instead of electrocautery to avoid dural shrinkage. Additionally, a wet cottonoid was placed on the cerebellar side dural flap to prevent dural dehydration. During dural closure, primary dural closure was always attempted. If not possible, a “plugging muscle” method was used for watertight dural closure. Results: The mean age was 54.1 ± 10.8 years (range, 24–85 years), and 238 (66.1%) were female. Primary MVD was performed in 345 (95.8%) patients. The mean operation time (from skin incision to skin closure) was 96.7 ± 33.0 min (range, 38–301 min). Primary dural closure was possible in 344 (95.6%) patients. The “plugging muscle method” was performed more frequently in patients older than 60 years (8 of 99 cases, 8.08%) than in younger cases (8 of 261 cases, 3.07%) (p = 0.039; chi-squared test). After surgery, 5 (1.4%) patients were treated for middle ear effusion, and another 5 (1.4%) patients experienced transient CSF rhinorrhea, which was spontaneously resolved within 1 to 7 days. No patients required additional treatments for CSF leakage. Conclusion: A simple technique using pulling stay sutures to stop bleeding from the dural edges and placing a wet cottonoid on the exposed dura can make primary dural closure easier.