Risk factors for postoperative meningitis after microsurgery for vestibular schwannoma

Management of Complications in Vestibular Schwannoma Surgery

Microsurgical removal of acoustic neuroma has advanced tremendously; however, complications still occur. Facial nerve injury is the most common detrimental complication and should take precedence over gross tumor removal in cases where there is an unfavorable tumor-facial nerve interface. Cerebrospinal fluid leakage can occur even with meticulous closure techniques and is generally treatable with either lumbar-subarachnoid drainage or revision wound closure. Meningitis is a serious complication that requires a high index of suspicion in the postoperative period. Other less common complications include intraoperative and postoperative vascular injuries. Early identification and treatment can prevent devastating outcomes.

Risk Factors of Postoperative Meningitis in Lateral Ventricular Trigone Meningiomas: A Clinical Analysis of 64 Patients

Purpose

Patients with intraventricular tumors are more susceptible to postoperative meningitis (POM) than other intracranial tumors. In this study, we explored the risk factors of POM in lateral ventricular trigone meningiomas (LVTMs).

Methods

Clinical features of 64 patients with LVTMs were analyzed. Age, gender, body mass index, medical history, intraoperative blood loss (IBL), intraventricular drainage placement, surgical duration, tumor grade, postoperative tumor cavity hemorrhage, and tumor size were included in univariate and multivariate analyses of POM.

Results

Of the 64 patients, 14 patients (21.9%) received diagnosis of POM. The univariate analysis revealed IBL ≥400 mL (odds ratio [OR], 9.012; p = 0.003), tumor size ≥50 cm³ (OR, 3.071; p = 0.080), and surgical duration ≥5 h (OR, 2.970; p = 0.085) were considered possible risk factors for POM (p < 0.10). Tumor size (R = 0.514) and surgical duration (R = 0.624) were significantly correlated with IBL (p < 0.05). In the multivariate analysis, only IBL was found to be an independent risk factor for POM.

Conclusion

The IBL ≥400 mL is independently associated with the increased risk of POM in LVTM patients. Our results demonstrate the importance of controlling IBL for preventing POM, especially in large tumors and long surgeries.

Multi-Layer Onlay Graft Using Hydroxyapatite Cement Placement without Cerebrospinal Fluid Diversion for Endoscopic Skull Base Reconstruction

Objective

The skull base reconstruction step, which prevents cerebrospinal fluid (CSF) leakage, is one of the most challenging steps in endoscopic skull base surgery (ESS). The purpose of this study was to assess the outcomes and complications of a reconstruction technique for immediate CSF leakage repair using multiple onlay grafts following ESS.

Methods

A total of 230 consecutive patients who underwent skull base reconstruction using multiple onlay grafts with fibrin sealant patch (FSP), hydroxyapatite cement (HAC), and pedicled nasoseptal flap (PNF) for high-flow CSF leakage following ESS at three institutions were enrolled. We retrospectively reviewed the medical and radiological records to analyze the preoperative features and postoperative results.

Results

The diagnoses included craniopharyngioma (46.8%), meningioma (34.0%), pituitary adenoma (5.3%), chordoma (1.6%), Rathke’s cleft cyst (1.1%) and others (n=21, 11.2%). The trans-planum/tuberculum approach (94.3%) was the most commonly adapted surgical method, followed by the trans-sellar and transclival approaches. The third ventricle was opened in 78 patients (41.5%). Lumbar CSF drainage was not performed postoperatively in any of the patients. Postoperative CSF leakage occurred in four patients (1.7%) due to technical mistakes and were repaired with the same technique. However, postoperative meningitis occurred in 13.5% (n=31) of the patients, but no microorganisms were identified. The median latency to the diagnosis of meningitis was 8 days (range, 2–38). CSF leakage was the unique risk factor for postoperative meningitis (p<0.001).

Conclusion

The use of multiple onlay grafts with FSP, HAC, and PNF is a reliable reconstruction technique that provides immediate and complete CSF leakage repair and mucosal grafting on the skull base without the need to harvest autologous tissue or perform postoperative CSF diversion. However, postoperative meningitis should be monitored carefully.

Dynamic Curve Analysis of Indicators Related to Lumbar Cistern Drainage for Postoperative Meningitis

OBJECTIVE

To analyze the dynamic curve of cerebrospinal fluid (CSF)-related indices in cases of postoperative meningitis after selective craniotomy and to provide reference data for the clinical treatment with lumbar cistern drainage (LCD).

METHODS

We conducted a retrospective study of LCD placement in 51 patients. Primary outcomes measured included dynamic changes of body temperature before and after intervention and cerebrospinal fluid biochemical parameters over the course of 13 days of catheter placement. We also assessed the bivariate correlation between white blood cell (WBC) count changes, polykaryocyte percentage, body temperature, and daily cerebrospinal fluid drainage volume. Finally, we analyzed the effect of average daily drainage volume, antibiotic choice, and surgical site on WBC count change curves.

RESULTS

After LCD, there was a statistically significant difference (P < 0.01) between the WBC count before drainage and on the fourth day of drainage. There was a negative correlation between the change curve of the WBC count and the change curve of daily drainage volume (r = -0.56). When the daily drainage volume was 250-300 mL/day, the change curve pattern of the WBC count was consistent with the overall trend, and there was no significant difference in the curve of the WBC count between different surgical sites (P > 0.05).

CONCLUSIONS

The WBC count can decrease significantly by day 4 after drainage, and placement of the LCD for 6-7 days is ideal. An average drainage volume of 250-300 mL/day is safe and effective.

Polymerase chain reaction targeting 16S ribosomal RNA for the diagnosis of bacterial meningitis after neurosurgery

OBJECTIVES

Bacterial and aseptic meningitis after neurosurgery can present similar clinical signs and symptoms. The aims of this study were to develop and test a molecular method to diagnose bacterial meningitis (BM) after neurosurgery.

METHODS

A 16S ribosomal RNA gene PCR-based strategy was developed using artificially inoculated cerebrospinal fluid (CSF) followed by sequencing. The method was tested using CSF samples from 43 patients who had undergone neurosurgery and were suspected to suffer from meningitis, and from 8 patients without neurosurgery or meningitis. Patients were classified into five groups, confirmed BM, probable BM, possible BM, unlikely BM, and no meningitis.

RESULTS

Among the samples from the 51 patients, 21 samples (41%) were culture-negative and PCR-positive. Of these, 3 (14%) were probable BM, 4 (19%) were possible BM, 13 (62%) were unlikely BM, and 1 (5%) was meningitis negative. Enterobacterales, non-fermenters (Pseudomonas aeruginosa and Acinetobacter baumannii), Staphylococcus haemolyticus, Granulicatella, Variovorax, and Enterococcus cecorum could be identified. In the group of patients with meningitis, a good agreement (3 of 4) was observed with the results of cultures, including the identification of species.

CONCLUSION

Molecular methods may complement the diagnosis, guide treatment, and identify non-cultivable microorganisms. We suggest the association of methods for suspected cases of BM after neurosurgery, especially for instances in which the culture is negative.