Cranioplasty infection case series

In 149 patients who underwent cranioplasty following decompressive craniectomy during the time period January 1998 to December 2012. Autologous bone flaps were sterilised in an autoclave and stored in a refrigerator at a temperature of 8 degrees above zero until cranioplasty was performed. Complications were registered and patient data were analysed in order to identify risk factors for surgical site infection and bone flap resorption after cranioplasty. Only the patients with a follow-up period of >24 months were included in the analysis of bone flap resorption (110 patients).

Surgical side infection occurred in only five patients (3.3%), whereas bone flap resorption developed in 22 patients (20%). The multivariate analysis of the presented data identified the operating time of >120 min (p = 0.0277; OR, 16.877; 95% CI, 1.364-208.906) and the presence of diabetes mellitus (p = 0.0016; OR, 54.261; 95% CI, 4.529-650.083) as independent risk factors of development of infection and the presence of ventriculo-peritoneal (VP) shunt (p < 0.0001; OR, 35.564; 95% CI, 9.962-126.960) as independent risk factor of development of the bone flap resorption.

Reimplantation of the autoclaved autologous bone flap following decompressive craniectomy is a simple and cheep alternative to other techniques and is available to any institution that provides autoclaving sterilisation services. This method is associated with a low rate of surgical site infection, but with a significant rate of the bone flap resorption ¹⁾.

Patients undergoing cranioplasty between 1999 and 2009 were identified from a prospectively maintained database. Records and imaging were reviewed retrospectively. Demographics, the initial craniectomy and subsequent cranioplasty surgeries, complications, and outcomes were recorded. A total of 187 patients underwent delayed cranioplasty using autologous bone flaps cryopreserved at -30°C following decompressive craniectomy. Indications for craniectomy were trauma (77.0%), stroke (16.0%), subarachnoid hemorrhage (2.67%), tumor (2.14%), and infection (2.14%). There were 64 complications overall (34.2%), the most common being infection (11.2%) and bone resorption (5.35%). After multivariate analysis, intraoperative cerebrospinal fluid (CSF) leak was significantly associated with infection, whereas longer duration of surgery and unilateral site were associated with resorption. Cranioplasty using frozen autologous bone is associated with a high rate of infective complications. Intraoperative CSF leak is a potentially modifiable risk factor. Meticulous dissection during cranioplasty surgery to minimize the chance of breaching the dural or pseudodural plane may reduce the chance of bone flap ²⁾.

88 operations were documented as 'Cranioplasty'. Data collection include patient demographics, type of cranioplasty used, time lapse between decompression and cranioplasty, seniority of the operating surgeon(s), antibiotic regimen and complications. Outcomes were recorded at the three-month follow-up.

The overall complication rate was 6.8%. The mean patient age was 36.2 years. 52.2% of patients had decompressive craniectomy for trauma, 11.3% had infectious pathology, 9% had subarachnoid haemorrhage, 9% had tumour with bone infiltration and 3.4% had stroke. 55.7% of patients had cranioplasty within 6 months of craniectomy. 61.3% of cranioplasties were with autologous bone, 20.4% titanium, 10.2% acrylic and 7.9% polyetheretherketone (PEEK). Significant complications included one case of infection, two cases of subgaleal haematoma and one extradural collection. No deaths were noted. No correlation was found between infection and the use of drains. 68.6% of cases were done by either a senior surgeon or a supervised registrar. There was an observable difference in complication rates in relation to the seniority and experience of the operator. However, patient numbers and complications were insufficient to achieve statistical significance. Strict antimicrobial prescribing was observed ³⁾.

in 125 patients decompressive craniectomy, of whom 33 died, 4 were lost to follow-up, and 1 (an infant) later underwent cranial remodeling. A CP was performed in the remaining 87 patients. Post-operative complications were recorded in 31 (36 %) patients of whom 22 lost their primary implant. Surgical site infection (SSI) and bone flap resorption (BFR) were the two most common complications, affecting 8 (9.2 %) and 14 (19.7 %) patients, respectively. Only BFR was associated with some of the recorded variables. Using multivariable logistic regression analysis, young age (OR = 0.94, 95 % CI 0.88-1.00, p = 0.04), bone flap fragmentation (OR = 14.3, 95 % CI 2.26-89, p = 0.005), long storage time (OR = 1.03, 95 % CI 1.00-1.04, p = 0.02) and Glasgow Outcome Scale at the time of cranioplasty (OR = 2.55, 95 % CI 1.04-6.23, p = 0.04) were found to be significant risk factors for bone flap resorption ⁴⁾.

Twenty-nine patients (male-to-female = 1:1.1; mean age 45 ± 14.7 years) who underwent decompressive craniectomy with placement of epidural bovine pericardium with subsequent cranioplasty were identified. The median interval between craniectomy and cranioplasty was 64 days, and autologous bone was used for cranioplasty in 86.2% of cases. The average size of cranial defect was 71.2 ± 28.5 cm(2). At the time of cranioplasty, no or minimal adhesions were found between the subcutaneous tissue and the epidural bovine pericardium. There were 2 (6.9%) infections, 2 (6.9%) patients had contusion after the cranioplasty, and no patient had a complication after cranioplasty that required reoperation.

Epidural bovine pericardium at the time of decompressive craniectomy facilitates dissection at the time of cranioplasty and is not associated with any additional risks ⁵⁾.

Of the 30 patients in the study, 28(93.3%) were males. The overall mean age was age 32.03±8.01 years (range: 20-48 years). Mean cranioplasty time was 66.2±11.50 days (range: 44-89 days). Major infection necessitating bone flap removal was found in 1(3.33%) patient, while minor scalp wound infections, treated with antibiotics and dressings were found in 2(6.66%). Cosmetic18 deformity was seen in 3(10%). Improved neurological outcome was noted in 21(70 %) patients; 6(20%) survived with a moderate to severe disability and 3(10%) remained in a vegetative state. No mortality was found after the procedure.

Early autologous bone replacement for decompressive hemicraniectomy in severe traumatic brain injury patients offered cost-effective, acceptable surgical and improve dneurological outcome ⁶⁾

Decompressive craniectomy (DC) requires later cranioplasty (CP) in survivors. However, if additional ventriculoperitoneal shunt (VPS) placement due to shunt-dependent hydrocephalus is necessary, the optimal timing of both procedures still remains controversial. From 2009 to 2014, 41 cranioplasty procedures with simultaneous or staged VPS placement were performed at the authors' institution. Patients were stratified into two groups according to the time from CP to VPS (“simultaneous” and “staged”). Patient characteristics, timing of CP and VPS, as well as procedure-related complications were assessed and analyzed.

Overall CP and VPS were performed simultaneously in 41% and in staged fashion in 59% of the patients. The overall complication rate was 27%. Patients who underwent simultaneous CP and VPS suffered significantly more often from complications compared to patients who underwent staged CP and VPS procedures (47% vs. 12%; p=0.03). Patients with simultaneous CP and VPS had a significantly higher rate of infectious postoperative complications compared to patients with staged procedures (p=0.003). On multivariate analysis, simultaneous CP and VPS procedure was the only significant predictor of postoperative complication after CP and VPS (p=0.03).

Schuss et al. provide detailed data on surgical timing and complications for cranioplasty and ventriculoperitoneal shunt placement after DC. The present data suggests that patients who undergo staged CP and VPS procedures might benefit from a lower complication rate. This might influence future surgical decision-making regarding optimal timing of CP and VPS placement ⁷⁾.

In 88 operations the overall complication rate was 6.8%. The mean patient age was 36.2 years. 52.2% of patients had decompressive craniectomy for trauma, 11.3% had infectious pathology, 9% had subarachnoid haemorrhage, 9% had tumour with bone infiltration and 3.4% had stroke. 55.7% of patients had cranioplasty within 6 months of craniectomy. 61.3% of cranioplasties were with autologous bone, 20.4% titanium, 10.2% acrylic and 7.9% polyetheretherketone (PEEK). Significant complications included one case of infection, two cases of subgaleal haematoma and one extradural collection. No deaths were noted. No correlation was found between infection and the use of drains. 68.6% of cases were done by either a senior surgeon or a supervised registrar. There was an observable difference in complication rates in relation to the seniority and experience of the operator. However, patient numbers and complications were insufficient to achieve statistical significance. Strict antimicrobial prescribing was observed.

Some potentially preventable complications have been addressed with a resulting rate of complications lower than other published reports. We use two standard adjuncts: the presence of a senior surgeon and strict antimicrobial regimens. We believe that our results could be transferrable to other units by following similar guidelines ⁸⁾.

In 45 patients from April 2011 through January 2012. The covariates studied were compared with occurrence versus nonoccurrence of infection. Univariate analysis was performed, followed by a multivariate analysis and development of independent logistic regression models with significance of 5%.

Wound infections were observed in 24% of cases. Patients treated with polymethyl methacrylate flaps had a 31% rate of infection compared with 12% in patients treated with autologous flaps, but the difference was not statistically significant (P = 0.279). Increased risk of infection was associated with performing CP during the same period of hospitalization as DC (45% vs. 8%; P = 0.006), recent systemic infection (53% vs. 10%; P = 0.003), a Glasgow Outcome Scale score lower than 4 (48% vs. none; P < 0.001), motor deficit (42% vs. 5%; P = 0.011), and lower levels of hemoglobin (P < 0.001). Another risk factor for infection was an interval between DC and CP of 29-84 days compared with >168 days (P = 0.007).

The incidence of wound infection was high. Risk factors included motor deficits, Glasgow Outcome Scale score <4, lower hemoglobin levels, recent systemic infections, interval between DC and CP of 29-84 days, and DC and CP performed during the same hospitalization. Performing CP during a different hospitalization may reduce the risk of graft infection because the hemoglobin level would be higher, and patients would be less dependent and free of recent infection ⁹⁾.

Patients with cranioplasty of a hostile cranial site at the University of Chicago between 2003 and 2012 were identified. They were stratified into three groups: chimeric free flap with vascularized bone (the vascular group), non-vascularized bone with local coverage (the non-vascular group) and non-vascularized bone with free flap (the mixed group). The primary outcome measure was a major complication in the year following cranioplasty, identified by flap or bone graft failure.

They reviewed 33 cases; 14 “vascular”, 13 “non-vascular”, and 8 “mixed”. There was no difference in flap or bone graft failure rates, which were 7% (1/14) for the vascular group, 8% (1/13) for the non-vascular group, and 0% for the mixed group (p = NS). Overall complication rate was statistically different between the three groups (p = 0.01). The non-vascular group had the lowest complication rate (31%). Based on our data we developed an assessment score (The University of Chicago CRAnial Severity Score of Hostility, CRASSH) for patient and treatment stratification.

Vascularized, non-vascularized and mixed reconstructive methods can be used successfully in these challenging situations. We offer the CRASSH to aid in aligning patients with the most appropriate autologous reconstruction method for their hostile cranial sites ¹⁰⁾.

Retrospective review of all patients who underwent cranioplasty following craniectomy from January, 2000, to December, 2011. Tested predictors were age, sex, diabetic status, hypertensive status, reason for craniectomy, urgency status of craniectomy, location of cranioplasty, reoperation for hematoma, hydrocephalus postcranioplasty, and material type. A multivariate logistic regression analysis was performed.

Three hundred forty-eight patients met the study criteria. Infection rate was 26.43% (92/348). Of these cases with infection, 56.52% (52/92) were superficial (supragaleal), 43.48% (40/92) were deep (subgaleal), and 31.52% (29/92) were present in both the supragaleal and subgaleal spaces. The predominant pathogen was coagulase-negative staphylococcus (30.43%) followed by methicillin-resistant Staphylococcus aureus (22.83%) and methicillin-sensitive Staphylococcus aureus (15.22%). Approximately 15.22% of all cultures were polymicrobial. Multivariate analysis revealed convex craniectomy, hemorrhagic stroke, and hydrocephalus to be associated with an increased risk of infection (OR = 14.41; P < 0.05, OR = 4.33; P < 0.05, OR = 1.90; P = 0.054, resp.).

Many of the risk factors for infection after cranioplasty are modifiable. Recognition and prevention of the risk factors would help decrease the infection's rate ¹¹⁾.

55 cranioplasties were performed. The material used for the cranioplasty was autologous bone in 42 cases, polyetheretherketone (PEEK) in 7 and methacrylate in 6. The average size of the bone defect was 69.5 (19.5-149.5)cm(2). The time elapsed between decompressive craniectomy and cranioplasty was 309 (25-1217) days. There were 10 complications (7 severe and 3 mild), an 18.2% complication rate. Statistically significant risk factors of complications were identified as a Barthel ≤70 (Odds ratio [OR] 22; 2.5-192; P=0.005), age over 45 years (OR 13.5; 1.5-115; P=0.01) and early surgery (≤85 days; OR 8; 1.69-37.03, P=0.004). After multivariate analysis, Barthel ≤70 and age over 45 years remained independent predictors of complications. Twenty-two (40%) of the 55 patients showed objective improvement. Early surgery (<85 days) increased the likelihood of improvement (OR 4.67; 1.05-20.83; P=0.035). Larger bone defects seemed to be related with improvement, but differences in defect size were not statistically significant (75.3 vs 65.6cm(2); P=0.1).

The complication rate of cranioplasty is higher than for other elective neurosurgical procedures. Older age, poorer functional situation (worse Barthel index score) and early surgery (≤85 days) are independent risk factors for complications. However, cranioplasty produces clinical benefits beyond protection and esthetic improvement. Earlier surgery and larger bone defects seem to increase the likelihood of clinical improvement ¹²⁾.

In 44 cases, the mean time from craniotomy to cranioplasty was 86 (95% CI: 63-109) days. Complications severe enough to warrant readmission or further surgery were found in 13 cases (30%). No statistically significant predictor of complication from cranioplasty was detected. The complication rate was similar to published data on cranioplasty using artificial prosthetic materials. Conclusions. AC in the trauma setting is a valid treatment option with a complication rate that seems no worse than other alternatives ¹³⁾.

Over a 10-year period, the details of 290 decompressive craniectomy procedures performed at our trauma and stroke center were recorded. Bone flaps from 110 patients were preserved in subcutaneous pockets (SPs), and 180 were preserved via cryopreservation (CP).

SSIs occurred in 20 cases (18.2%) in the SP group and 20 cases (11.1%) in the CP group (P=0.129). After dividing each group according to the traumatic brain injury (TBI) etiologies, we found that in the SP group, the SSI rates in the TBI and non-TBI patients were 17.3% and. 20.7% (P=0.899), respectively, and in the TBI- and non-TBI CP-group patients, the SSI rates were 11.9% and. 9.7% (P=0.864), respectively. The average decrease in bone flap thicknesses were 1.14 mm in the SP group (n=34) and 1.89 mm in the CP group (n=57), and this difference was significant (P=0.039).

In this series, the SSI rates were similar in the SP and CP groups. There was no significant difference when the patients were grouped by TBI etiology. The incidence of bone flap resorption in the CP group was higher than that in the SP group. However, identifying of the method that yields superior results might depend on the individual surgeon's preference and the available equipment ¹⁴⁾.

A retrospective study included 74 consecutive patients treated with decompressive craniectomy during the time period May 1998 to October 2010 for various non-traumatic conditions causing increased intracranial pressure due to brain swelling. Complications were registered and patient data was analyzed in a search for predictive factors.

Fifty out of the 74 patients (67.6 %) survived and underwent delayed cranioplasty. Of these, 47 were eligible for analysis. Six patients (12.8 %) developed SSI following the replacement of autologous cryopreserved bone, whereas bone resorption occurred in two patients (4.3 %). No factors predicted a statistically significant rate of SSI, however, prolonged procedural time and cardiovascular comorbidity tended to increase the risk of SSI.

SSI and bone flap resorption are the most frequent complications associated with the reimplantation of autologous cryopreserved bone after decompressive craniectomy. Prolonged procedural time and cardiovascular comorbidity tend to increase the risk of SSI ¹⁵⁾.

A retrospective review was conducted for all cranioplasties performed at our center between January 2001 to March 2011, using autologous bone which was cryopreserved according to institutional protocol. During this period the operative and cryopreservation protocol remained the same. All patient records including charts, notes and laboratory findings were reviewed with a specific focus to identify infections.

Of the 88 patients included in the study, only 3 (3.40%) patients were found to show signs of infection. Of these, two patients had superficial surgical site infections which resolved with oral antibiotics (Co-Amoxiclav 1 gm BD for 7 days). However the third patient developed deep surgical site infection requiring re-exploration and washout. All three patients had complete resolution of infection with preservation of autologous bone.

Despite our method of keeping the bone flap in freezer at - 26°C we have reported an acceptable rate of infection and raised the notion whether there is a justification for sophisticated and costly equipment for bone flap preservation, especially in resource depleted setups ¹⁶⁾.