Factors affecting graft infection after cranioplasty

doi:10.1016/j.jocn.2007.09.022

Journal of Clinical Neuroscience

Volume 15, Issue 10, October 2008, Pages 1115-1119

https://doi.org/10.1016/j.jocn.2007.09.022 Get rights and content

Abstract

The aim of this study was to identify the risk factors associated with bone grafts infection after cranioplasty. Eighty-four cranioplasties were performed on 75 patients between 2002 and 2006. Cryopreserved bone grafts were used as graft material in group 1 and polymethylmethacrylate (PMMA) was used in group 2. Risk factors including age, gender, time intervals between craniectomy and cranioplasty, mechanism of injury, number of procedures, graft material, and the Glasgow Coma Scale score were compared between groups. Swab culture results and bone graft infection were assessed in group 1. Multiple procedures before cranioplasty and an inadequate time interval between craniectomy and cranioplasty increase the risk of infection after cranioplasty. Swab culture results, age, gender, mechanism of injury, graft material and Glasgow Coma Scale score are not related to infection. The use of PMMA was associated with a relatively low risk of infection (6.25%). Risk of graft infection was not associated with the choice of graft material in the present study. Multiple procedures and insufficient time intervals increase the risk of infection. Interrupting the wound healing process may be the cause of infection. PMMA is a safe material for cranioplasty regardless of previous infection.

Introduction

Although many diverse materials have been proposed for cranioplasty,[1], [2], [3], [4], [5], [6], [7], [8], [9], [10], [11] autogenous bone grafts and polymethylmethacrylate (PMMA) are preferred in most institutions. Autogenous bone grafts can be preserved subcutaneously in the abdominal wall or frozen and stored in the freezer. Repair of cranial defects using cryopreserved bone grafts was first reported in the 1950s.[12], [13], [14] This method is relatively inexpensive, ensures a good fit, allows bone growth and replacement of host cells, and carries no risk of disease transmission. PMMA, one of the most commonly used alloplastic materials for cranioplasty, is considered a secondary option for cranioplasty at our institution. A major concern with bone grafts for cranioplasty is infection. To decrease the infection rate, we follow similar guidelines to the American Association of Tissue Banks and the European Association of Tissue Banks. Aerobic and anaerobic cultures and sensitivity tests are performed for the skull bone during craniectomy and/or before cranioplasty. In this retrospective study we review the results for 75 patients who underwent cranioplasty using cryopreserved bone grafts or PMMA between 2002 and 2006. We correlate swab culture results and bone graft infections and identify risk factors associated with graft infection.

Section snippets

Materials and methods

Between January 2002 and May 2006, 75 patients underwent 84 cranioplasty procedures at Chang Gung Memorial Hospital, Chia-Yi. The patients were divided into two groups. Group 1 included 52 patients who underwent 52 cranioplasties using cryopreserved bone grafts. Group 2 included 23 patients (20 male, three female) who each underwent an initial PMMA cranioplasty. Additionally, patients from both groups who required a repeat PMMA cranioplasty (five males and two females from group 1 plus two

Results

The overall infection rate for the 84 procedures was 10.7% (9/84). Table 1 and Table 2 show the numbers of infected and non-infected grafts for each factor analysed. The infection rate was 13.5% (7/52) for group 1 (Table 1) and 6.25% (2/32) for group 2 (Table 2).

Discussion

Cranioplasty using autogenous bone grafts was introduced in the 1950s. Cryopreservation and subcutaneous preservation are the most common methods of bone storage.[15], [16], [17], [18], [19], [20] Autogenous bone grafts have the advantages of being genetically identical and potentially growing. The disadvantages are that resorption and infection can occur. In neurosurgery, bone grafts for cranioplasty are autogenous. Although the risks of immunologic reaction and disease transmission are very

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Cited by (148)

Cranioplasty in Depressed Skull Fractures: A Narrative Review of the Literature
2024, Interdisciplinary Neurosurgery: Advanced Techniques and Case Management
Decompressive craniectomy (DC) is performed routinely following traumatic brain injury (TBI), including depressed fracture (DSF), and following other mass-occupying conditions such as large ischemic strokes. DC could be followed by cranioplasty (CP), which is associated with cosmetic and protective benefits. The appropriate choice of implant, ideal timing, complications, and avoiding reoperation are challenges that neurosurgeons face in CP.
Our goal is to delineate validatable guidelines for physicians to make decisions based on the latest data in the literature.
CP is not just a cosmetic procedure but also a therapeutic option for patients with depressed fractures. Patients with decompressive craniectomies secondary to other conditions can also develop decompressive craniectomy syndrome needing CP. The choice of materials used for reconstruction is critical to ensure safety and effectiveness. Different alloplastic grafts, such as polymethyl methacrylate, hydroxyapatite, dynamic titanium mesh, and complex mesh patterns, are used in CP, and the advantages and disadvantages must be considered prior to the surgery. Complications are divided into intra- and post-operative groups, and understanding these complications enables the surgeon to diminish the chances of occurrence and enhance surgical consequences. The proper timing of CP following decompressive craniectomy remains controversial.
CP is a simple and useful neurosurgical intervention in those with skull defects. CP provides protective and cosmetic benefits. The main objective of the surgical intervention is to restore the skull to its original shape, protect the brain from further injury and avoid decompressive craniectomy syndrome.
Lowering Cranioplasty Infection Incidence with Novel Bone Flap Storage Protocol: A Retrospective Cohort Study
2024, World Neurosurgery
After craniectomy, autologous bone flaps may be stored using wet or dry cryopreservation. After brain edema subsides, they are replaced during an operation termed cranioplasty. Cranioplasty is associated with 15% infection incidence.
We conducted a retrospective comparison of infection outcomes between wet and dry cryopreservation of cranioplasty bone flaps. Historically, bone flaps were stored utilizing wet cryopreservation—bone flap storage in 1 L of lactated Ringer's solution containing 80 mg gentamicin and 2 g nafcillin in a sterile plastic container secured in an unsterile plastic bag. Our newer dry cryopreservation protocol involved storage in gauze soaked in 80 mg gentamicin and 2 g nafcillin within a 3-layer sterile bag system.
A total of 119 autologous bone flaps were included, with median follow-up of 3.9 months from cranioplasty. Overall, 10.9% became infected, requiring subsequent surgery; 18.4% of 49 bone flaps stored using wet cryopreservation became infected compared with only 5.7% of 70 dry cryopreservation bone flaps (P = 0.038; relative risk [RR] 0.311; absolute risk reduction 12.7%). Tobacco use (P = 0.076; RR 3.17) was not associated with increased infection risk. Infection incidence was similar for traumatic craniectomy indications compared to the other indications (12.0% trauma vs. 10.1% other; P = 0.750). On average, infected cranioplasty patients spent 8.5 more days hospitalized and faced increased risk of additional complications.
Dry cryopreservation significantly decreases infection after cranioplasty when compared with wet cryopreservation, and this mitigates additional morbidity, mortality, and costs attributable to cranioplasty infection. Other nonmodifiable risk factors for cranioplasty infection were identified.
An update on a persisting challenge: A systematic review and meta-analysis of the risk factors for surgical site infection post craniotomy
2024, American Journal of Infection Control
Surgical site infections (SSIs) postcraniotomy continue to impose a significant burden on health care systems and patient outcomes. It is, therefore, important to understand their risk factors in order to promote effective preventative measures. This meta-analysis aims to provide a comprehensive, up-to-date analysis of the risk factors associated with SSIs in neurosurgical procedures.
A systematic review was conducted as per preferred reporting items for systematic reviews and meta-analysis guidelines to explore existing primary evidence on the risk factors for SSIs postcraniotomy. A comprehensive search of MEDLINE, EMBASE, and Pubmed was performed from database inception up to June 2023. 43 studies were included in the meta-analysis, encompassing a total of 68,881 patients.
The strongest predictor for SSIs was found to be cerebrospinal fluid (CSF) leak (OR: 8.91, CI: 4.30-18.44). Other significant factors included infratentorial surgery (OR: 0.43, CI: 0.31-0.61), emergency surgery (OR: 1.41, CI: 1.05-1.91), reintervention (OR: 3.19, CI: 1.77-5.75), prolonged operative time (mean difference: 33.25; CI: 18.83-47.67), hospital length of stay (mean difference: 0.60; CI: 0.23-0.98) and intracranial pressure monitor (ICPM) insertion (OR: 1.81; CI: 1.06-3.11). Contrarily, sex, body mass index (BMI), diabetes, antibiotic prophylaxis, immunosuppressive agents, trauma, use of artificial implants did not demonstrate statistical significance.
This meta-analysis provides an up-to-date and comprehensive evaluation of risk factors for SSIs postcraniotomy. It emphasizes the need for preventive strategies, particularly against CSF leaks, and calls for further research to elucidate the intricate relationships between these factors.
The Adjustable Cranial Plate: A Novel Implant Designed to Eliminate the Need for Cranioplasty Surgery Following a Hemicraniectomy Operation
2023, World Neurosurgery
Decompressive hemicraniectomy (DHC) is performed to relieve life-threatening intracranial pressure elevations. After swelling abates, a cranioplasty is performed for mechanical integrity and cosmesis. Cranioplasty is costly with high complication rates. Prior attempts to obviate second-stage cranioplasty have been unsuccessful. The Adjustable Cranial Plate (ACP) is designed for implantation during DHC to afford maximal volumetric expansion with later repositioning without requiring a second major operation.
The ACP has a mobile section held by a tripod fixation mechanism. Centrally located gears adjust the implant between the up and down positions. Cadaveric ACP implantation was performed. Virtual DHC and ACP placement were done using imaging data from 94 patients who had previously undergone DHC to corroborate our cadaveric results. Imaging analysis methods were used to calculate volumes of cranial expansion.
The ACP implantation and adjustment procedures are feasible in cadaveric testing without wound closure difficulties. Results of the cadaveric study showed total volumetric expansion achieved was 222 cm³. Results of the virtual DHC procedure showed the volume of cranial expansion achieved by removing a standardized bone flap was 132 cm³ (range, 89–171 cm³). Applied to virtual craniectomy patients, the total volume of expansion achieved with the ACP implantation operation was 222 cm³ (range, 181–263 cm³).
ACP implantation during DHC is technically feasible. It achieves a volume of cranial expansion that will accommodate that observed following survivable hemicraniectomy operations. Moving the implant from the up to the down position can easily be performed as a simple outpatient or inpatient bedside procedure, thus potentially eliminating second-stage cranioplasty procedures.
Predictive factors for bone flap infection after cranioplasty
2022, Journal of Clinical Neuroscience
Bone flap infection is often experienced as a complication of cranioplasty. The aim of this study was to investigate predictors of graft infection, including patient-specific and surgery-specific factors. We retrospectively reviewed cases at our institution who underwent cranioplasty following craniectomy for traumatic brain injury, epidural hematoma, subdural hematoma, intracranial hemorrhage, cerebral infarction, subarachnoid hemorrhage, arteriovenous malformation, and bone flap infection after craniotomy. A total of 192 patients were included in this analysis. The graft infection rate was 8.3% (16/192). Smoking (odds ratio [OR] 3.09, 95% confidence interval [CI] 1.03–12.24; p = 0.04), allergy (OR 6.15, 95% CI 1.50–17.31; p < 0.01), and body temperature on postoperative day 1 (OR 2.57, 95% CI 1.14–5.78; p = 0.02) were found to be independent predictors for graft infection. Based on receiver operating characteristic analysis, a body temperature on postoperative day 1 higher than 38.0 °C was selected as the optimal cut-off value for predicting infection after cranioplasty. The sensitivity and specificity were 68% and 72%, respectively. Smoking, allergy, and body temperature on postoperative day 1 predicted complications leading to graft infection. Patients with a fever of 38 °C or higher on day 1 after cranioplasty should be carefully monitored for graft infection.
Cryopreservation of autologous bone flaps following decompressive craniectomy: A new method reduced positive cultures without increase in post-cranioplasty infection rate
2022, Brain and Spine
Cranioplasty (CP) after decompressive craniectomy (DC) is a common neurosurgical procedure. Implementation of European Union (EU) directives recommending bacterial cultures before cryopreservation, lead to increased number of autologous bone flaps being discarded due to positive cultures. A new method for handling bone flaps prior to cryopreservation, including the use of pulsed lavage, was developed.
The aim was to evaluate the effect of a new method on proportion of positive bacterial cultures and surgical site infection (SSI) following CP surgery.
Sixty-one bone flaps from 53 consecutive DC surgery patients were retrospectively included and the study period was divided into before and after method implementation. Patient demographics, laboratory and culture results, type of CP and occurrence of SSI were analyzed.
Twenty-six and 18 bone flaps were available for analysis during the first and second period, respectively. The proportion of positive bacterial cultures was higher in the first period compared to the second (n = 9(35%) vs 0(0%); p = 0.001), and thus the use of custom made implants was considerably higher in the first study period (p = 0.001). There was no difference in the frequency of post-cranioplasty SSI between the first and second study period (n = 3 (11.5%) vs 1 (4.8%), p = 0.408).
The new method for handling bone flaps resulted in a lower frequency of positive bacterial cultures, without increased frequency of post-cranioplasty SSI, thus demonstrating it is safe to use, allows compliance with the EU-directives, and may reduce unnecessary discarding of bone flaps.

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Clinical StudyFactors affecting graft infection after cranioplasty

Abstract

Introduction

Section snippets

Materials and methods

Results

Discussion

Implants for cranioplasty

Otolaryngol Clin North Am

The use of bone grafts and alloplastic materials in cranioplasty

Clin Orthop Rel Res

The use of screw fixation of methylmethacrylate to reconstruct large craniofacial contour defects

Eur J Plast Surg

Technical considerations in the use of polymethylmethacrylate in cranioplasty

J Long Term Effects Med Implants

Cranioplasty with polymethylmethacrylate. The clinico-statistical considerations

Minerva Chir

Frontal cranioplasty: Risk factors and choice of cranial vault reconstructive material

Plast Reconstr Surg

Management of extensive and difficult cranial defects

J Neurosurg

Hydroxyapatite cement: An alternative for craniofacial skeletal contour refinements

Br J Plast Surg

Hydroxyapatite cement. I. Basic chemistry and histologic properties

Arch Otolaryngol Head Neck Surg

Use of frozen cranial bone flaps for autogenous and homologous grafts in cranioplasty and spinal interbody fusion

J Neurosurg

The bone-bank in neurosurgery

Br J Surg

The use of refrigerated autogenous bone flaps for cranioplasty

J Neurosurg

Autogenous skull cranioplasty: Fresh and preserved (frozen), with consideration of the cellular response

Neurosurgery

Clinical Study
Factors affecting graft infection after cranioplasty