Complications of decompressive craniectomy for head injury

Complications Associated with Decompressive Craniectomy: A Systematic Review

Decompressive craniectomy (DC) has been used for many years in the management of patients with elevated intracranial pressure and cerebral edema. Ongoing clinical trials are investigating the clinical and cost effectiveness of DC in trauma and stroke. While DC has demonstrable efficacy in saving life, it is accompanied by a myriad of non-trivial complications that have been inadequately highlighted in prospective clinical trials. Missing from our current understanding is a comprehensive analysis of all potential complications associated with DC. Here, we review the available literature, we tabulate all reported complications, and we calculate their frequency for specific indications. Of over 1500 records initially identified, a final total of 142 eligible records were included in our comprehensive analysis. We identified numerous complications related to DC that have not been systematically reviewed. Complications were of three major types: (1) Hemorrhagic (2) Infectious/Inflammatory, and (3) Disturbances of the CSF compartment. Complications associated with cranioplasty fell under similar major types, with additional complications relating to the bone flap. Overall, one of every ten patients undergoing DC may suffer a complication necessitating additional medical and/or neurosurgical intervention. While DC has received increased attention as a potential therapeutic option in a variety of situations, like any surgical procedure, DC is not without risk. Neurologists and neurosurgeons must be aware of all the potential complications of DC in order to properly advise their patients.

Management of the temporal muscle during cranioplasty: technical note

Over the past 2 decades there has been a resurgence of interest in the use of decompressive craniectomy in the management of neurological emergencies. While technically straightforward, the procedure is associated with a number of complications relating to the initial decompression and subsequent cranioplasty. One complication that has received relatively little attention relates to the management of the temporal muscle. Here, through an illustrative case, the author describes a novel method of minimizing dissection of the temporal muscle during a cranioplasty procedure. Rather than placing a synthetic material over the dura mater to prevent adhesions or dissecting the muscle off the dura, the dura was opened and reflected laterally, pedicled to the temporal muscle. The dural defect was closed with a dural substitute, and the bone flap was secured in a routine fashion. The temporal muscle was then secured in its anatomical position. At the 6-month follow-up, radiological and clinical examination confirmed the restoration of muscle volume with excellent cosmetic and functional results. Opening the dura on a temporal muscle pedicle does not represent a routine form of surgical reconstruction; however, the use of this technique may have some advantages especially in young patients who have made a good recovery and for whom facial aesthetics may be particularly important.

Deformation of a Titanium Calvarial Implant following Trauma: A Case Report

Alloplastic material is widely used for the reconstruction of calvarial defects. The objective of this article is to describe the effect of mechanical impact on a titanium calvarial implant and to discuss mechanical properties of alternative implant materials. The patient is a 19-year-old man who was involved in a traffic accident and underwent decompressive craniectomy for an extensive subdural hematoma. Reimplantation of the skull flap was complicated by infection and the flap had to be removed. The remaining cranial defect was closed with a titanium plate. The recovery was without complications. One year later, the patient was hit on the titanium plate, during a soccer match, by the elbow of a fellow player. The implant deflected inward, leaving a visible indentation of the cranial vault. Fortunately, there were no significant neurological symptoms and radiography did not show any signs of damage or pressure on the brain parenchyma. The patient had no aesthetic complaints regarding the shape. Thus, there was no indication to remove the plate. This case illustrates the limits of the protection offered by titanium cranioplasty.

Low Incidence of Bone Flap Resorption After Native Bone Cranioplasty in Adults

OBJECTIVE

Cranioplasty via use of the patient's autologous bone is performed often after craniectomy procedures. Bone resorption remains a matter of concern in patients with native bone cranioplasty. The objective of this study was to evaluate the rate of native bone resorption in adults and review associated factors that may increase the risk of resorption.

METHODS

This is a single-center retrospective cohort study that assessed consecutive patients who had cranioplasty via use of the patient's native bone flap. A total of 114 patients were identified. Electronic medical records were reviewed for demographic and operative data.

RESULTS

The mean age was 51.2 years. The main indications for initial craniectomy included subarachnoid hemorrhage (SAH) in 50.9%, intracerebral hemorrhage in 17.5%, ischemic stroke in 14.9%, and trauma in 13.2% of patients. Mean interval between craniectomy and cranioplasty was 6 months. Mean follow-up after cranioplasty was 25 months. Bone resorption occurred in 3 patients (2.7%): at 6 months in a 30-year-old woman who presented with SAH followed by decompressive craniectomy and cranioplasty 3.5 months later; at 19 months in a 67-year-old female patient who presented with intracerebral hemorrhage followed by decompressive craniectomy and cranioplasty 6 months later; and at 9 months in a 50-year-old man who presented with SAH followed by craniectomy for clip ligation and cranioplasty 3 months later. Two of these patients underwent replacement of the native flap with synthetic material.

CONCLUSIONS

The rate of autologous bone flap resorption in adult patients undergoing cranioplasty is low even after a mean interval for cranioplasty of 6 months.

Craniotomy or Decompressive Craniectomy for Acute Subdural Hematomas: Surgical Selection and Clinical Outcome

Objective

Craniotomy (CO) and decompressive craniectomy (DC) are two main surgical options for acute subdural hematomas (ASDH). However, optimal selection of surgical modality is unclear and decision may vary with surgeon's experience. To clarify this point, we analyzed preoperative findings and surgical outcome of patients with ASDH treated with CO or DC.

Methods

From January 2010 to December 2014, data for 46 patients with ASDH who underwent CO or DC were retrospectively reviewed. The demographic, clinical, imaging and clinical outcomes were analyzed and statistically compared.

Results

Twenty (43%) patients underwent CO and 26 (57%) patients received DC. In DC group, preoperative Glascow Coma Scale was lower (p=0.034), and more patient had non-reactive pupil (p=0.004). Computed tomography findings of DC group showed more frequent subarachnoid hemorrhage (p=0.003). Six month modified Rankin Scale showed favorable outcome in 60% of CO group and 23% of DC group (p=0.004). DC was done in patient with more unfavorable preoperative features (p=0.017). Patients with few unfavorable preoperative features (<6) had good outcome with CO (p<0.001).

Conclusion

In selective cases of few unfavorable clinical findings, CO may also be an effective surgical option for ASDH. Although DC remains to be standard of surgical modality for patients with poor clinical status, CO can be an alternative considering the possible complications of DC.

A randomized controlled trial comparing autologous cranioplasty with custom-made titanium cranioplasty

OBJECTIVE Autologous bone is usually used to reconstruct skull defects following decompressive surgery. However, it is associated with a high failure rate due to infection and resorption. The aim of this study was to see whether it would be cost-effective to use titanium as a primary reconstructive material. METHODS Sixty-four patients were enrolled and randomized to receive either their own bone or a primary titanium cranioplasty. All surgical procedures were performed by the senior surgeon. Primary and secondary outcome measures were assessed at 1 year after cranioplasty. RESULTS There were no primary infections in either arm of the trial. There was one secondary infection of a titanium cranioplasty that had replaced a resorbed autologous cranioplasty. In the titanium group, no patient was considered to have partial or complete cranioplasty failure at 12 months of follow-up (p = 0.002) and none needed revision (p = 0.053). There were 2 deaths unrelated to the cranioplasty, one in each arm of the trial. Among the 31 patients who had an autologous cranioplasty, 7 patients (22%) had complete resorption of the autologous bone such that it was deemed a complete failure. Partial or complete autologous bone resorption appeared to be more common among young patients than older patients (32 vs 45 years old, p = 0.013). The total cumulative cost between the 2 groups was not significantly different (mean difference A$3281, 95% CI $-9869 to $3308; p = 0.327). CONCLUSIONS Primary titanium cranioplasty should be seriously considered for young patients who require reconstruction of the skull vault following decompressive craniectomy. Clinical trial registration no.: ACTRN12612000353897 ( anzctr.org.au ).

According to which factors in severe traumatic brain injury craniectomy could be beneficial

BACKGROUND

To investigate the clinical outcome at 101 patients undergoing decompressive craniectomy (DC) after severe traumatic brain injury (TBI).

METHODS

Age, Glasgow Coma Scale (GCS) at the time of intubation, and the intraoperative intracranial pressure (ICP) were recorded. Formal DC was performed in all cases and the square surface of bone flap was calculated in cm(2) based on the length and the width from computed tomography scan.

RESULTS

The difference of good neurological recovery (Glasgow outcome score 4-5), between patients with ICP ≤20 mmHg, GCS ≥5, age ≤60 years, and bone flap ≥130 cm(2) and those with ICP >20 mmHg, GCS <5, age >60 years, and bone flap <130 cm(2), was statistically significant.

CONCLUSION

Although the application of DC in severe TBI is controversial and the population in this study is small, our study demonstrates the threshold of the specific factors (patient age, ICP and GCS on the day of the surgery and the size of the bone flap) which may help in the decision of performing DC. Furthermore, this study proves that the different combinations and mainly at the same time involvement of all prognostic parameters (age <60, GCS <5, bone flap ≥130 cm(2), and ICP ≤20 at time of DC surgery) allow a better outcome.

The Effect of Cranioplasty on Cerebral Hemodynamics as Measured by Perfusion Computed Tomography and Doppler Ultrasonography

Cranioplasties are performed to protect the brain and correct cosmetic defects, but there is growing evidence that this procedure may result in neurological improvement. We prospectively studied cranioplasties performed at our hospital over a 5-year period. The National Institute of Health Stroke Scale and Barthel index were recorded prior to and within 72 h after the cranioplasty. A perfusion computed tomography (PCT) and transcranial Doppler sonography (TCDS) were performed prior to and 72 h after the surgery. For the PCT, regions irrigated by the anterior cerebral artery, the middle cerebral artery (MCA), the posterior cerebral artery, and the basal ganglia were selected, as well as the mean values for the hemisphere. The sonography was performed in the sitting and the supine position for the MCA and internal carotid. The velocities, pulsatility index, resistance index, and Lindegaard ratio (LR) were obtained, as well as a variation value for the LR (ΔLR = LR sitting - LR supine). Fifty-four patients were included in the study. Of these, 23 (42.6%) patients presented with objective improvement. The mean cerebral blood flow of the defective side (m-CBF-d) increased from 101.86 to 117.17 mL/100 g/min (p = 0.064), and the m-CBF of the healthy side (m-CBF-h) increased from 128.14 to 145.73 mL/100 g/min (p = 0.028). With regard to the TCDS, the ΔLR was greater on the defective side prior the surgery in those patients who showed improvement (1.295 vs. -0.714; p = 0.002). Cranioplasty resulted in clinical improvement in 40% of the patients, with an increase in the post-surgical CBF. The larger variations in the LR when the patient is moved from the sitting to the supine position might predict the clinical improvement.

Integrative review: postcraniotomy pain in the brain tumour patient

AIM

To conduct an integrative review to examine evidence of pain and associated symptoms in adult (≥21 years of age), postcraniotomy, brain tumour patients hospitalized on intensive care units.

BACKGROUND

Healthcare providers believe craniotomies are less painful than other surgical procedures. Understanding how postcraniotomy pain unfolds over time will help inform patient care and aid in future research and policy development.

DESIGN

Systematic literature search to identify relevant literature. Information abstracted using the Theory of Unpleasant Symptoms' concepts of influencing factors, symptom clusters and patient performance. Inclusion criteria were indexed, peer-reviewed, full-length, English-language articles. Keywords were 'traumatic brain injury', 'pain, post-operative', 'brain injuries', 'postoperative pain', 'craniotomy', 'decompressive craniectomy' and 'trephining'.

DATA SOURCES

Medline, OVID, PubMed and CINAHL databases from 2000-2014.

REVIEW METHOD

Cooper's five-stage integrative review method was used to assess and synthesize literature.

RESULTS

The search yielded 115 manuscripts, with 26 meeting inclusion criteria. Most studies were randomized, controlled trials conducted outside of the United States. All tested pharmacological pain interventions. Postcraniotomy brain tumour pain was well-documented and associated with nausea, vomiting and changes in blood pressure, and it impacted the patient's length of hospital stay, but there was no consensus for how best to treat such pain.

CONCLUSION

The Theory of Unpleasant Symptoms provided structure to the search. Postcraniotomy pain is experienced by patients, but associated symptoms and impact on patient performance remain poorly understood. Further research is needed to improve understanding and management of postcraniotomy pain in this population.

Analysis of Factors Contributing to Infections After Cranioplasty: A Single-Institution Retrospective Chart Review

OBJECTIVE

Cranioplasty is one of the most common neurosurgical procedures, yet has one of the greatest rates of infection among cranial operations. Although studies have reported on cranioplasty complications, it is unclear what factors contribute to the high rate of infection. This study aims to determine which patient characteristics and operative factors lead to postcranioplasty infections.

METHODS

This was a retrospective chart review of 186 patients. Factors analyzed included sex, reason for cranioplasty, type of infection, medical comorbidities, and surgical factors.

RESULTS

The overall infection rate was 24%. Skin flora was the most common pathogen. Wound dehiscence and presence of a postoperative fluid collection were associated significantly with a greater rate of infection (P < 0.001), whereas the use of autologous bone flap and a state of immunosuppression trended toward statistical significance (P = 0.075 and P = 0.089, respectively). Male sex, history of previous infection, history of craniectomy for trauma, cranioplasty size, and time to cranioplasty were not found to be significant factors related to cranioplasty infection.

CONCLUSIONS

Although wound dehiscence and postoperative fluid collections were associated significantly with infection in this study, the number in each sample size was small, and further studies with a larger number of patients in each subgroup is necessary to validate our findings.

The Risk Factors for Hydrocephalus and Subdural Hygroma after Decompressive Craniectomy in Head Injured Patients

Objective

The present study aims to investigate 1) the risk factors for hydrocephalus and subdural hygroma (SDG) occurring after decompressive craniectomy (DC), and 2) the association between the type of SDG and hydrocephalus.

Methods

We retrospectively reviewed the clinical and radiological features of 92 patients who underwent DC procedures after severe head injuries. The risk factors for developing post-traumatic hydrocephalus (PTH) and SDG were analyzed. Types of SDGs were classified according to location and their relationship with hydrocephalus was investigated.

Results

Ultimately, 26.09% (24/92) of these patients developed PTH. In the univariate analyses, hydrocephalus was statically associated with large bone flap diameter, large craniectomy area, bilateral craniectomy, intraventricular hemorrhage, contralateral or interhemisheric SDGs, and delayed cranioplasty. However, in the multivariate analysis, only large craniectomy area (adjusted OR=4.66; p=0.0239) and contralateral SDG (adjusted OR=6.62; p=0.0105) were significant independent risk factors for developing hydrocephalus after DC. The incidence of overall SDGs after DC was 55.43% (51/92). Subgroup analysis results were separated by SDG types. Statistically significant associations between hydrocephalus were found in multivariate analysis in the contralateral (adjusted OR=5.58; p=0.0074) and interhemispheric (adjusted OR=17.63; p=0.0113) types.

Conclusion

For patients who are subjected to DC following severe head trauma, hydrocephalus is associated with a large craniectomy area and contralateral SDG. For SDGs after DC that occur on the interhemispherical or controlateral side of the craniectomy, careful follow-up monitoring for the potential progression into hydrocephalus is needed.

The Effect of Fenestration of Lamina Terminalis on the Vasospasm and Shunt-Dependent Hydrocephalus in Patients Following Subarachnoid Haemorrhage

BACKGROUND AND AIMS

SAH (Sub Arachnoid Haemorrhage) is a life threatening that is associated with complications such as vasospasm and shunt-dependent hydrocephalus. The purpose of this study was to assess the effect of FLT (Fenestration of Lamina Terminalis) on the incidence of vasospasm and shunt-dependent hydrocephalus in ACoA (Anterior Communicating Artery) aneurismal in SAH.

MATERIALS AND METHODS

The data of 50 ruptured ACoA aneurism patients were selected during the year 2001-2009 admitted to Imam Hussein hospital, Tehran, IR. In a randomized double-blind trial patients assigned in two group {with fenestration (FLT, n=25), without fenestration (No FLT, n=25)}. All patients underwent craniotomy by a single neurosurgeon. Patient's age, sex, Hunt-Hess grade, Fisher grade, vasospasm, presence of hydrocephalus and incidences of shunt-dependent hydrocephalus were compared between groups.

RESULTS

There were no significant differences among groups in relation to demographic characteristics, neurological scale scores (Hunt-Hess grade) and the severity of the SAH (Fisher grade) (p>0.05). The rate of hydrocephalus on admission, were 24% and 16% in FLT and no FLT group respectively (p>0.05). The shunt placement postoperatively in FLT and no FLT group were 16% and 12% respectively (p>0.05). The clinical vasospasm was 20% and 24% in FLT and no FLT group respectively (p>0.05).

CONCLUSION

Despite FLT can be a safe method there were not significant differences of FLT on the incidence of vasospasm and shunt-dependent hydrocephalus. A systematic evaluation with multisurgeon, multicentre and with greater sample size to disclose reality is suggested.

Analyses Using Micro-CT Scans and Tissue Staining on New Bone Formation and Bone Fusion According to the Timing of Cranioplasty via Frozen Autologous Bone Flaps in Rabbits : A Preliminary Report

Objective

The timing of cranioplasty and method of bone flap storage are known risk factors of non-union and resorption of bone flaps. In this animal experimental study, we evaluated the efficacy of cranioplasty using frozen autologous bone flap, and examined whether the timing of cranioplasty after craniectomy affects bone fusion and new bone formation.

Methods

Total 8 rabbits (male, older than 16 weeks) were divided into two groups of early cranioplasty group (EG, 4 rabbits) and delayed cranioplasty group (DG, 4 rabbits). The rabbits of each group were performed cranioplasty via frozen autologous bone flaps 4 weeks (EG) and 8 weeks (DG) after craniectomy. In order to obtain control data, the cranioplasty immediate after craniectomy were made on the contralateral cranial bone of the rabbits (control group, CG).The bone fusion and new bone formation were evaluated by micro-CT scan and histological examination 8 weeks after cranioplasty on both groups.

Results

In the micro-CT scans, the mean values of the volume and the surface of new bone were 50.13±7.18 mm³ and 706.23±77.26 mm² in EG, 53.78±10.86 mm³ and 726.60±170.99 mm² in DG, and 31.51±12.84 mm³ and 436.65±132.24 mm² in CG. In the statistical results, significant differences were shown between EG and CG and between DG and CG (volume : p=0.028 and surface : p=0.008). The histological results confirmed new bone formation in all rabbits.

Conclusion

We observed new bone formation on all the frozen autologous bone flaps that was stored within 8 weeks. The timing of cranioplasty may showed no difference of degree of new bone formation. Not only the healing period after cranioplasty but the time interval from craniectomy to cranioplasty could affect the new bone formation.

Dhaga Technique for Tissue Plane Preservation after Decompressive Craniectomy: Comparison of New Technique with Institutional Standard

BACKGROUND

During cranioplasty after decompressive craniectomy, the temporalis muscle is firmly attached to the dural patch and intermixed with fibrotic tissue leading to considerable difficulty in dissecting the plane between the dura, galea and the temporalis muscle. This leads to increased surgical time, intraoperative blood loss, risk of complications and also affects rehabilitation. We have developed the "dhaga technique," which aids in preserving the plane between the muscle and dura in order to improve outcomes. Here we describe our technique and also compare the "dhaga technique" with the generally accepted standard procedure.

METHODS

A retrospective review was carried out of all patients undergoing cranioplasty following decompressive craniectomy either through the "dhaga technique" or the institutional standard (control group). Both techniques were compared using intra operative blood loss, duration of surgery and any complications as study variables.

RESULTS

There were 133 patients were included in the study. The control group included 68 patients who underwent the procedure according to institutional standard, and 65 patients were included in the "dhaga technique group." Both groups were well matched for baseline characteristics. Patients in the "dhaga technique" group had statistically significant lower operating time (P value = 0.037) and intra operative blood loss (P value = 0.025). However, there was no significant difference in complications.

CONCLUSION

The utilization of "dhaga technique" can potentially improve outcomes and reduce costs by decreasing operative time and blood loss. Moreover, the temporalis muscle preservation in the "dhaga technique" may also enhance aesthetic outcomes and chewing, which were not assessed in this study. There were no differences in complication between the two techniques.

Bone Flap Resorption Following Cranioplasty after Decompressive Craniectomy: Preliminary Report

Objective

Resorption of autologous bone flap grafts is a known long-term complication of cranioplasty following decompressive craniectomy (DC). We analyzed our data to identify risk factors for bone flap resorption (BFR) following cranioplasty.

Methods

A total of 162 patients who underwent cranioplasty following DC due to life-threatening elevated intracranial pressure between October 2003 and December 2012, were included in our investigation. Follow-up exceeded one year.

Results

BFR occurred as a long-term complication in 9 of the 162 patients (5.6%). The affected patients consisted of individuals who had undergone DC for traumatic brain injury (TBI; n=4), for subarachnoid hemorrhage (SAH; n=3), for cerebral infarction (n=1), and intracerebral hemorrhage (n=1). Logistic regression analysis identified no significant risk factors for BFR.

Conclusion

TBI and SAH as initial diagnoses are more often associated with BFR than other diagnoses. This finding may influence future surgical decision making, especially in patients with possible risk factors for BFR. A prospective study with a large number of patients is needed to identify potential predictors of BFR such as bone flap sterilization and preservation.

Decompressive craniectomy in severe traumatic brain injury: prognostic factors and complications

OBJECTIVE

To analyze the clinical characteristics, complications and factors associated with the prognosis of severe traumatic brain injury among patients who undergo a decompressive craniectomy.

METHODS

Retrospective study of patients seen in an intensive care unit with severe traumatic brain injury in whom a decompressive craniectomy was performed between the years 2003 and 2012. Patients were followed until their discharge from the intensive care unit. Their clinical-tomographic characteristics, complications, and factors associated with prognosis (univariate and multivariate analysis) were analyzed.

RESULTS

A total of 64 patients were studied. Primary and lateral decompressive craniectomies were performed for the majority of patients. A high incidence of complications was found (78% neurological and 52% nonneurological). A total of 42 patients (66%) presented poor outcomes, and 22 (34%) had good neurological outcomes. Of the patients who survived, 61% had good neurological outcomes. In the univariate analysis, the factors significantly associated with poor neurological outcome were postdecompressive craniectomy intracranial hypertension, greater severity and worse neurological state at admission. In the multivariate analysis, only postcraniectomy intracranial hypertension was significantly associated with a poor outcome.

CONCLUSION

This study involved a very severe and difficult to manage group of patients with high morbimortality. Intracranial hypertension was a main factor of poor outcome in this population.

Complications of cranioplasty using a bone flap sterilised by autoclaving following decompressive craniectomy

BACKGROUND

Increasing use of decompressive craniectomies has led to a corresponding number of cranioplasties performed to replace the subsequent bone defect created. We aimed to evaluate the morbidity associated with cranioplasty using an autologous bone flap sterilised in an autoclave.

METHODS

We retrospectively analysed data from 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).

RESULTS

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.

CONCLUSIONS

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.

What happens to the bone flap? Long-term outcome after reimplantation of cryoconserved bone flaps in a consecutive series of 92 patients

BACKGROUND

Reimplantation of cryoconserved autologous bone flaps is a standard procedure after decompressive craniotomies. Aseptic necrosis and resorption are the most frequent complications of this procedure. At present there is no consensus regarding the definition of the relevant extent and indication for surgical revision. The objective of this retrospective analysis was to identify the incidence of bone flap resorption and the optimal duration of follow-up.

METHODS

Between February 2009 and March 2012, 100 cryoconserved autologous bone flaps were reimplanted at the Department of Neurosurgery, Inselspital Bern. Three patients were not available for follow-up, and five patients died before follow-up. All patients underwent follow-up at 6 weeks and a second follow-up more than 12 months postoperatively. A clinical and CT-based score was developed for judgment of relevance and decision making for surgical revision.

RESULTS

Mean follow-up period was 21.6 months postoperatively (range: 12 to 47 months); 48.9 % (45/92) of patients showed no signs of bone flap resorption, 20.7 % (19/92) showed minor resorption with no need for surgical revision, and 30.4 % (28/92) showed major resorption (in 4 % of these the bone flap was unstable or collapsed).

CONCLUSIONS

Aseptic necrosis and resorption of reimplanted autologous bone flaps occurred more frequently in our series of patients than in most reports in the literature. Most cases were identified between 6 and 12 months postoperatively. Clinical observation or CT scans of patients with autologous bone flaps are recommended for at least 12 months. Patient-specific implants may be preferable to autologous bone flaps.

Simultaneous cranioplasty and subdural-peritoneal shunting for contralateral symptomatic subdural hygroma following decompressive craniectomy

BACKGROUND

Contralateral subdural hygroma caused by decompressive craniectomy tends to combine with external cerebral herniation, causing neurological deficits.

MATERIAL AND METHODS

Nine patients who underwent one-stage, simultaneous cranioplasty and contralateral subdural-peritoneal shunting were included in this study. Clinical outcome was assessed by Glasgow Outcome Scale as well as Glasgow Coma Scale, muscle power scoring system, and complications.

RESULTS

Postoperative computed tomography scans demonstrated completely resolved subdural hygroma and reversed midline shifts, indicating excellent outcome. Among these 9 patients, 4 patients (44%) had improved GOS following the proposed surgery. Four out of 4 patients with lethargy became alert and orientated following surgical intervention. Muscle strength improved significantly 5 months after surgery in 7 out of 7 patients with weakness. Two out of 9 patients presented with drowsiness due to hydrocephalus at an average time of 65 days after surgery. Double gradient shunting is useful to eliminate the respective hydrocephalus and contralateral subdural hygroma.

CONCLUSION

The described surgical technique is effective in treating symptomatic contralateral subdural hygroma following decompressive craniectomy and is associated with an excellent structural and functional outcome. However, subdural-peritoneal shunting plus cranioplasty thoroughly resolves the subdural hygroma collection, which might deteriorate the cerebrospinal fluid circulation, leading to hydrocephalus.

Decompressive craniectomy (DC) at the non-injured side of the brain has the potential to improve patient outcome as measured with computational simulation

OBJECTIVE

Decompressive craniectomy (DC) is efficient in reducing the intracranial pressure in several complicated disorders such as traumatic brain injury (TBI) and stroke. The neurosurgical procedure has indeed reduced the number of deaths. However, parallel with the reduced fatal cases, the number of vegetative patients has increased significantly. Mechanical stretching in axonal fibers has been suggested to contribute to the unfavorable outcome. Thus, there is a need for improving treatment procedures that allow both reduced fatal and vegetative outcomes. The hypothesis is that by performing the DC at the non-injured side of the head, stretching of axonal fibers at the injured brain tissue can be reduced, thereby having the potential to improve patient outcome.

METHODS

Six patients, one with TBI and five with stroke, were treated with DC and where each patient's pre- and postoperative computerized tomography (CT) were analyzed and transferred to a finite element (FE) model of the human head and brain to simulate DC both at the injured and non-injured sides of the head. Poroelastic material was used to simulate brain tissue.

RESULTS

The computational simulation showed slightly to substantially increased axonal strain levels over 40 % on the injured side where the actual DC had been performed in the six patients. However, when the simulation DC was performed on the opposite, non-injured side, there was a substantial reduction in axonal strain levels at the injured side of brain tissue. Also, at the opposite, non-injured side, the axonal strain level was substantially lower in the brain tissue. The reduced axonal strain level could be verified by analyzing a number of coronal sections in each patient. Further analysis of axial slices showed that falx may tentatively explain part of the different axonal strain levels between the DC performances at injured and opposite, non-injured sides of the head.

CONCLUSIONS

By using a FE method it is possible to optimize the DC procedure to a non-injured area of the head thereby having the potential to reduce axonal stretching at the injured brain tissue. The postoperative DC stretching of axonal fibers may be influenced by different anatomical structures including falx. It is suggested that including computational FE simulation images may offer guidance to reduce axonal strain level tailoring the anatomical location of DC performance in each patient.

The influence of decompressive craniectomy on the development of hydrocephalus: a review

Decompressive craniectomy (DC) is widely used to treat intracranial hypertension following traumatic brain injury (TBI) or cerebral vascular disease. Many studies have discussed complications of this procedure, and hydrocephalus is a common complication of DC. To further evaluate the relationship between DC and hydrocephalus, a review of the literature was performed. Numerous complications may arise after DC, including contusion or hematoma expansion, epilepsy, herniation of the cortex through a bone defect, CSF leakage through the scalp incision, infection, subdural effusion, hydrocephalus and “syndrome of the trephined”. Several hydrocephalus predictors were identified; these included DC, distance from the midline, hygroma, age, injury severity, subarachnoid or intraventricular hemorrhage, delayed time to craniotomy, repeated operation, and duraplasity. However, results differed among studies. The impact of DC on hydrocephalus remains controversial.

The effect of craniectomy size on mortality, outcome, and complications after decompressive craniectomy at a rural trauma center

Introduction:

Decompressive craniectomy (DC) has increasing support with current studies suggesting an improvement in both survival rates and outcomes with this intervention. However, questions surround this procedure; specifically, no evidence has indicated the optimal craniectomy size. Larger craniectomy is thought to better decrease intracranial pressure, but with a possible increase in complication rates. Our hypothesis is that a larger craniectomy may improve mortality and outcome, but may increase complication rates.

Materials and Methods:

A retrospective observational therapeutic study was undertaken to determine if craniectomy size is related to complication rates, mortality, or outcome. Our institution's Trauma Registry was searched for patients undergoing DC. Craniectomy size was measured by antero-posterior (AP) diameter. Mortality, outcome (through admission and discharge Glasgow Coma Score and Glasgow Outcome Scale), and complications (such as re-bleeding, re-operation, hygroma, hydrocephalus, infection, and syndrome of the trephined) were noted. Complications, mortality, and outcome were then compared to craniectomy size, to determine if any relation existed to support our hypothesis.

Results:

20 patients met criteria for inclusion in this study. Craniectomy size as measured by AP diameter was correlated with a statistically significant improvement in mortality within the group. All patients with a craniectomy size less than 10 cm died. However, outcome was not significantly related to craniectomy size in the group. Similarly, complication rates did not differ significantly compared to craniectomy size.

Discussion:

This study provides Level 3 evidence that craniectomy size may be significantly related to improved mortality within our group, supporting our initial hypothesis; however, no significant improvement in outcome was seen. Similarly, in contrast to our hypothesis, complication rates did not significantly correlate with craniectomy size.

Cryopreservation versus subcutaneous preservation of autologous bone flaps for cranioplasty: comparison of the surgical site infection and bone resorption rates

OBJECTIVE

Decompressive craniectomy is performed to treat malignant brain hypertension. Surgical site infection (SSI) and bone resorption are common complications following cranioplasty, and the storage method that minimizes such complication has yet to be identified.

METHODS

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).

RESULTS

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).

CONCLUSIONS

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.

Calvarial fracture patterns on CT imaging predict risk of a delayed epidural hematoma following decompressive craniectomy for traumatic brain injury

BACKGROUND AND PURPOSE

The development of a delayed epidural hematoma as a result of decompressive craniectomy represents an urgent and potentially lethal complication in traumatic brain injury. The goal of this study was to determine the incidence of delayed epidural hematoma and whether patterns of skull fractures on the preoperative CT scan could predict risk of a delayed epidural hematoma.

MATERIALS AND METHODS

We retrospectively evaluated medical records and imaging studies for patients with acute traumatic brain injury who underwent a decompressive craniectomy during a 9-year period. We compared patterns of skull fractures contralateral to the side of the craniectomy with the occurrence of a postoperative delayed epidural hematoma.

RESULTS

In a series of 203 patients undergoing decompressive craniectomy for acute traumatic brain injury, the incidence of a delayed epidural hematoma complication was 6% (12 of 203). All 12 patients who developed a delayed epidural hematoma had a contralateral calvarial fracture on preoperative CT at the site where the delayed epidural hematoma subsequently formed. A contralateral calvarial fracture has perfect sensitivity (100%) for subsequent development of delayed epidural hematoma in our study population. Moreover, a contralateral calvarial fracture involving 2 or more bone plates had an especially high diagnostic odds ratio of 41 for delayed epidural hematoma.

CONCLUSIONS

Recognition of skull fracture patterns associated with delayed epidural hematoma following decompressive craniectomy may reduce morbidity and mortality by prompting early postoperative intervention in high-risk situations.

Asymmetric optic nerve sheath diameter as an outcome factor following cranioplasty in patients harboring the 'syndrome of the trephined'

Decompressive craniectomy (DC) is gaining an increasing role in the neurosurgical treatment of intractable intracranial hypertension, but not without complications. A rare complication is the "syndrome of the trephined" (ST). It occurs when the forces of gravity overwhelm intracranial pressures, leading the brain to become sunken.

OBJECTIVE

To determine the usefulness of asymmetric optic nerve sheath diameter (ONSD) as an outcome factor after cranioplasty.

METHOD

We followed-up 5 patients submitted to DC and diagnosed with ST. All were submitted to brain MRI to calculate the ONSD.

RESULTS

Only two patients presented an asymmetric ONSD, being ONSD larger at the site of craniectomy. Surprisingly these patients had a marked neurological improvement after cranioplasty. They became independent a week after and statistically earlier than others.

CONCLUSION

It is presumed that the presence of an asymmetric ONSD in trephined patients is an independent factor of good outcome after cranioplasty.

Decompressive craniectomy for management of traumatic brain injury: an update

Decompressive craniectomy (DC) for the management of severe traumatic brain injury (TBI) has a long history but remains controversial. Although DC has been shown to improve both survival and functional outcome in patients with malignant cerebral infarctions, evidence of benefit in patients with TBI is decidedly more mixed. Craniectomy can clearly be life-saving in the presence of medically intractable elevations of intracranial pressure. Craniectomy also has been consistently demonstrated to reduce "therapeutic intensity" in the ICU, to reduce the need for intracranial-pressure-directed and brain-oxygen-directed interventions, and to reduce ICU length of stay. Still, the only randomized trial of DC in TBI failed to demonstrate any benefit. Studies of therapies for TBI, including hemicraniectomy, are challenging owing to the inherent heterogeneity in the pathophysiology observed in this disease. Craniectomy can be life-saving for patients with severe TBI, but many questions remain regarding its ideal application, and the outcome remains highly correlated with the severity of the initial injury.

Pontine encephalocele and abnormalities of the posterior fossa following transclival endoscopic endonasal surgery

OBJECT

Transclival endoscopic endonasal surgery (EES) has recently been used for the treatment of posterior fossa tumors. The optimal method of reconstruction of large clival defects following EES has not been established.

METHODS

A morphometric analysis of the posterior fossa was performed in patients who underwent transclival EES to compare those with observed postoperative anatomical changes (study group) to 50 normal individuals (anatomical control group) and 41 matched transclival cases with preserved posterior fossa anatomy (case-control group) using the same parameters. Given the absence of clival bone following transclival EES, the authors used the line between the anterior commissure and the basion as an equivalent to the clival plane to evaluate the location of the pons. Four parameters were studied and compared in the two populations: the pontine location/displacement, the maximum anteroposterior (AP) diameter of the pons, the maximum AP diameter of the fourth ventricle, and the cervicomedullary angle (CMA). All measurements were performed on midsagittal 3-month postoperative MR images in the study group.

RESULTS

Among 103 posterior fossa tumors treated with transclival EES, 14 cases (13.6%) with postoperative posterior fossa anatomy changes were identified. The most significant change was anterior displacement of the pons (transclival pontine encephalocele) compared with the normal location in the anatomical control group (p < 0.0001). Other significant deformities were expansion of the AP diameter of the pons (p = 0.005), enlargement of the fourth ventricle (p = 0.001), and decrease in the CMA (p < 0.0001). All patients who developed these changes had undergone extensive resection of the clival bone (> 50% of the clivus) and dura. Nine (64.3%) of the 14 patients were overweight (body mass index [BMI] > 25 kg/m(2)). An association between BMI and the degree of pontine encephalocele was observed, but did not reach statistical significance. The use of a fat graft as part of the reconstruction technique following transclival EES with dural opening was the single significant factor that prevented pontine displacement (p = 0.02), associated with 91% lower odds of pontine encephalocele (OR = 0.09, 95% CI 0.01-0.77). The effect of fat graft reconstruction was more pronounced in overweight/obese individuals (p = 0.04) than in normal-weight patients (p = 0.52). Besides reconstruction technique, other noticeable findings were the tendency of younger adults to develop pontine encephalocele (p = 0.05) and the association of postoperative meningitis with the development of posterior fossa deformities (p = 0.05). One patient developed a transient, recurrent subjective diplopia; all others remained asymptomatic.

CONCLUSIONS

Significant changes in posterior fossa anatomy that have potential clinical implications have been observed following transclival transdural EES. These changes are more common in younger patients or those with meningitis and may be associated with BMI. The use of a fat graft combined with the vascularized nasoseptal flap appears to minimize the risk of pontine herniation following transclival EES with dural opening.

Temporal changes in CT perfusion values before and after cranioplasty in patients without symptoms related to external decompression: a pilot study

INTRODUCTION

Little is known about hemodynamic disturbances affecting cerebral hemispheres in traumatic brain injury (TBI) after cranioplasty.

METHODS

We prospectively investigated six stable TBI patients who underwent cranioplasty more than 90 days after effective decompressive craniectomy. Computerized tomography perfusion (CTP) studies and evaluation of clinical outcome were performed for each patient before cranioplasty and at 7 days and 3 months after surgery. Cerebral blood flow (CBF), cerebral blood volume (CBV) and mean transit time (MTT) were measured in multiple cortical circular regions positioned in cranioplasty-treated and contralateral hemispheres.

RESULTS

Neither complications associated with cranioplasty nor changes in outcome were observed. On the treated side, CBF and CBV values were higher before and 7 days after cranioplasty than at 3 months after surgery, whereas MTT values were lower at 7 days than at 3 months after surgical treatment.

CONCLUSIONS

Our results indicate that cortical perfusion progressively declines in the cranioplasty treated hemisphere but remains stable in the contralateral hemisphere after surgery and suggest that CTP can represent a promising tool for a longitudinal analysis of hemodynamic abnormalities occurring in TBI patients after cranioplasty. In addition, these data imply a possible role of cranioplasty in restoring flow to meet the prevailing metabolic demand.

Comprehensive cognitive and cerebral hemodynamic evaluation after cranioplasty

Decompressive craniectomy is an established procedure to lower intracranial pressure and can save patients' lives. However, this procedure is associated with delayed cognitive decline and cerebral hemodynamics complications. Studies show the benefits of cranioplasty beyond cosmetic aspects, including brain protection, and functional and cerebrovascular aspects, but a detailed description of the concrete changes following this procedure are lacking. In this paper, the authors report a patient with trephine syndrome who underwent cranioplasty; comprehensive cognitive and cerebral hemodynamic evaluations were performed prior to and following the cranioplasty. The discussion was based on a critical literature review.

Autologous vascularized dural wrapping for temporalis muscle preservation and reconstruction after decompressive craniectomy: report of twenty-five cases

Temporalis muscle reconstruction is a necessary step during frontotemporal cranioplasty ensuing decompressive craniectomy (DC). During this procedure, scarring between the temporalis muscle and the dural layer may lead to complicated muscle dissection, which carries an increased risk of dura and muscle damage. At time of DC, temporalis muscle wrapping by an autologous vascularized dural flap can later on facilitate dissection and rebuilding during the subsequent cranioplasty. In a span of 2 years, we performed 57 DCs for different etiologies. In 30 cases, the temporalis muscle was isolated by wrapping its inner surface using the autologous dura. At cranioplasty, the muscle could easily be dissected from the duraplasty. The inner surface was easily freed from the autologous dural envelope, and reconstruction achieved in an almost physiological position. Follow-up examinations were held at regular intervals to disclose signs of temporalis muscle depletion. Twenty-five patients survived to undergo cranioplasty. Muscle dissection could always be performed with no injury to the dural layer. No complications related to temporalis muscle wrapping were recorded. Face asymmetry developed in four cases but it was always with bone resorption. None of the patients with a good neurological recovery reported functional or aesthetic complaints. In our experience, temporalis muscle wrapping by vascularized autologous dura proved to be effective in preserving its bulk and reducing its adhesion to duraplasty, thereby improving muscle dissection and reconstruction during cranioplasty. Functional and aesthetic results were satisfying, except in cases of bone resorption.

Cranioplasty with custom-made titanium plates--14 years experience

BACKGROUND

There is no consensus on which material is best suited for repair of cranial defects.

OBJECTIVE

To investigate the outcomes following custom-made titanium cranioplasty.

METHODS

The medical records for all patients who had titanium cranioplasty at 2 major neurosurgical centers in Western Australia were retrieved and analyzed for this retrospective cohort study.

RESULTS

Altogether, 127 custom-made titanium cranioplasties on 113 patients were included. Two patients had 3 titanium cranioplasties and 10 patients had 2. Infected bone flap (n = 61, 54%), either from previous craniotomy or autologous cranioplasty, and contaminated bone flap (n = 16, 14%) from the initial injury were the main reasons for requiring titanium cranioplasty. Complications attributed to titanium cranioplasty were common (n = 33, 29%), with infection being the most frequent complication (n = 18 patients, 16%). Complications were, on average, associated with an extra 7 days of hospital stay (interquartile range 2-17). The use of titanium as the material for the initial cranioplasty (P = .58), the presence of skull fracture(s) (P > .99) or scalp laceration(s) (P = .32) at the original surgery, and proven local infection before titanium cranioplasty (P = .78) were not significantly associated with an increased risk of infection. Infection was significantly more common after titanium cranioplasty for large defects (hemicraniectomy [39%] and bifrontal craniectomy [28%]) than after cranioplasty for small defects (P = .04).

CONCLUSION

Complications after using titanium plate for primary or secondary cranioplasty were common (29%) and associated with an increased length of hospital stay. Infection was a major complication (16%), and this suggested that more vigorous perioperative infection prophylaxis is needed for titanium plate cranioplasty.

Traumatic brain injury: pathophysiology, monitoring, and mechanism-based care

Traumatic brain injury, which may be blunt or penetrating, begins altering intracranial physiology at the moment of impact as primary brain trauma. This article differentiates blunt versus penetrating brain trauma, primary versus secondary brain injury, and subsequent intracranial pathophysiology. Discussion and case study correlate intracranial pathophysiology and multisystem influences on evolving brain injury with mechanism-based interventions to modulate brain components (brain, blood, and cerebrospinal fluid volumes). The discussion also explores the effects of controlled ventilation, cardiopulmonary physiology, and global physiologic state on secondary injury, control of intracranial pressure, and recovery.

Shape modifications of porous hydroxyapatite prostheses to improve rigid implant fixation: Experience in 12 cases

BACKGROUND

Various methods of fixation have been described for custom made hydroxyapatite cranial implants. Their poor malleability limits most of the common used fixation techniques because of the high risk of cranioplasty's fracturing or higher exposure to infections. We present our experience with a new fixation technique, based on an appositely premodified hydroxyapatite implants.

METHODS

In a 2-year time period, 12 patients underwent cranioplasty by a modified custom made porous hydroxyapatite implant. Once the three-dimensional computer model of the prostheses was performed, three semicircular extensions placed at strategic positions were drawn and the final prosthesis was realized. At surgery, holes fitting the extensions were drilled into the skull borders and the implant was easily embedded inside the defect. Small titanium meshes overlying the extensions were fixed by screws to the surrounding bone.

RESULTS

A minimal increase of operative times was recorded, with drilling and fixation requiring additional 30 and 15 minutes, respectively. Optimal contact between cranioplasty and skull borders was always observed at control computed tomography (CT) scans. Permanent rigid fixation was obtained in all cases, with good functional and aesthetic results at follow-up.

CONCLUSIONS

Modifications of hydroxyapatite implants are obtained without additional costs. The minimal increase of operative times is largely counterbalanced by optimal fixation results. Finally, the bone drilling and the immediate proximity of bone to prosthesis might enhance the potential for osteogenesis and osteointegration.

Progressive epidural hematoma in patients with head trauma: incidence, outcome, and risk factors

Progressive epidural hematoma (PEDH) after head injury is often observed on serial computerized tomography (CT) scans. Recent advances in imaging modalities and treatment might affect its incidence and outcome. In this study, PEDH was observed in 9.2% of 412 head trauma patients in whom two CT scans were obtained within 24 hours of injury, and in a majority of cases, it developed within 3 days after injury. In multivariate logistic regression, patient gender, age, Glasgow Coma Scale (GCS) score at admission, and skull fracture were not associated with PEDH, whereas hypotension (odds ratio (OR) 0.38, 95% confidence interval (CI) 0.17-0.84), time interval of the first CT scanning (OR 0.42, 95% CI 0.19-0.83), coagulopathy (OR 0.36, 95% CI 0.15-0.85), or decompressive craniectomy (DC) (OR 0.46, 95% CI 0.21-0.97) was independently associated with an increased risk of PEDH. The 3-month postinjury outcome was similar in patients with PEDH and patients without PEDH (χ(2) = 0.07, P = 0.86). In conclusion, epidural hematoma has a greater tendency to progress early after injury, often in dramatic and rapid fashion. Recognition of this important treatable cause of secondary brain injury and the associated risk factors may help identify the group at risk and tailor management of patients with TBI.

Decompressive Craniectomy in Acute Brain Injury – Lifting the lid on Neurosurgical Practice

Decompressive craniectomy (DC) is an effective method of controlling rising intracranial pressure (ICP) refractory to medical treatment in a range of conditions: traumatic brain injury in both adults and children, malignant middle cerebral artery infarction and following subarachnoid haemorrhage. Herein, we describe its indications, prognosis, current operative methods and postoperative management.

Brainstem hemorrhage following decompressive craniectomy

Decompressive craniectomy (DC) is used for the management of refractory raised intracranial pressure, but the impact of DC on surgical outcome is still controversial. We report a 21-year-old man admitted to our hospital after a road traffic accident. The brain CT scan revealed a left hemispheric acute subdural hematoma. After DC, he developed a brainstem hemorrhage. Recovery was, however, good.