Hinge/floating craniotomy as an alternative technique for cerebral decompression: a scoping review

Decompressive craniectomy in trauma: What you need to know

ABSTRACT

Decompressive craniectomy (DC) is a surgical procedure in which a large section of the skull is removed, and the underlying dura mater is opened widely. After evacuating a traumatic acute subdural hematoma, a primary DC is typically performed if the brain is bulging or if brain swelling is expected over the next several days. However, a recent randomized trial found similar 12-month outcomes when primary DC was compared with craniotomy for acute subdural hematoma. Secondary removal of the bone flap was performed in 9% of the craniotomy group, but more wound complications occurred in the craniectomy group. Two further multicenter trials found that, whereas early neuroprotective bifrontal DC for mild to moderate intracranial hypertension is not superior to medical management, DC as a last-tier therapy for refractory intracranial hypertension leads to reduced mortality. Patients undergoing secondary last-tier DC are more likely to improve over time than those in the standard medical management group. The overall conclusion from the most up-to-date evidence is that secondary DC has a role in the management of intracranial hypertension following traumatic brain injury but is not a panacea. Therefore, the decision to offer this operation should be made on a case-by-case basis. Following DC, cranioplasty is warranted but not always feasible, especially in low- and middle-income countries. Consequently, a decompressive craniotomy, where the bone flap is allowed to "hinge" or "float," is sometimes used. Decompressive craniotomy is also an option in a subgroup of traumatic brain injury patients undergoing primary surgical evacuation when the brain is neither bulging nor relaxed. However, a high-quality randomized controlled trial is needed to delineate the specific indications and the type of decompressive craniotomy in appropriate patients.

Effectiveness of hinge craniotomy as an alternative to decompressive craniectomy for acute subdural hematoma

BACKGROUND

Acute subdural hematoma (ASDH) is a life-threatening condition, and hematoma removal is necessary as a lifesaving procedure when the intracranial pressure is highly elevated. However, whether decompressive craniectomy (DC) or conventional craniotomy (CC) is adequate remains unclear. Hinge craniotomy (HC) is a technique that provides expansion potential for decompression while retaining the bone flap. At our institution, HC is the first-line operation instead of DC for traumatic ASDH, and we present the surgical outcomes.

METHODS

From January 1, 2017, to December 31, 2022, 372 patients with traumatic ASDH were admitted to our institution, among whom 48 underwent hematoma evacuation during the acute phase. HC was performed in cases where brain swelling was observed intraoperatively. If brain swelling was not observed, CC was selected. DC was performed only when the brain was too swollen to allow replacement of the bone flap. We conducted a retrospective analysis of patient demographics, prognosis, and subsequent cranial procedures for each technique.

RESULTS

Of the 48 patients, 2 underwent DC, 23 underwent HC, and 23 underwent CC. The overall mortality rate was 20.8% (10/48) at discharge and 30.0% (12/40) at 6 months. The in-hospital mortality rates for DC, HC, and CC were 100% (2/2), 21.7% (5/23), and 13.0% (3/23), respectively. Primary brain injury was the cause of death in five patients whose brainstem function was lost immediately after surgery. No fatalities were attributed to the progression of postoperative brain herniation. In only one case, the cerebral contusion worsened after the initial surgery, leading to brain herniation and necessitating secondary DC.

CONCLUSIONS

The strategy of performing HC as the first-line operation for ASDH did not increase the mortality rate compared with past surgical reports and required secondary DC in only one case.

Managing the "big black brain" in low resource setting: A case report of early outcome after hinge craniotomy

Background

The big black brain (BBB) phenomenon is described as an infant's response to an acute subdural hematoma (SDH). It is characterized by hypodensity and swelling of the supratentorial compartment as a whole. Numerous factors may contribute to the formation of the BBB. Due to its high morbidity and mortality, the management of BBB is still debatable. In this report, we describe a 2-month-old boy who had bilateral hemispheric hypodensity and underwent hinge craniotomy.

Case Description

The patient was referred to our hospital with decreased consciousness. The patient had a history of seizures and cardiopulmonary arrest. There is no history of trauma. The computed tomography revealed a subacute SDH on the left parietal and occipital lobe along with hypodensity in both hemispheres with preservation of posterior fossa, consistent with hemispheric hypodensity. We performed a hinge craniotomy for the emergency procedure and evacuated only the hemisphere with the bleeding side. The patient cried spontaneously 24 hours after the procedure and was discharged six days later.

Conclusion

Early outcomes of hinge craniotomy as an alternative procedure for treating the BBB were positive. However, long-term outcomes, particularly the infant's development, should be monitored.

Hinge craniotomy versus standard decompressive hemicraniectomy: an experimental preclinical comparative study

INTRODUCTION

Decompressive craniectomy (DC) is the most common surgical procedure to manage increased intracranial pressure (ICP). Hinge craniotomy (HC), which consists of fixing the bone operculum with a pivot, is an alternative method conceived to avoid some DC-related complications; nonetheless, it is debated whether it can provide enough volume expansion. In this study, we aimed to analyze the volume and ICP obtained with HC using an experimental cadaver-based preclinical model and compare the results to baseline and DC.

METHODS

Baseline conditions, HC, and DC were compared on both sides of five anatomical specimens. Volume and ICP values were measured with a custom-made system. Local polynomial regression was used to investigate volume differences.

RESULTS

The area of the bone opercula resulting from measurements was 115.55 cm2; the mean supratentorial volume was 955 mL. HC led to intermediate results compared to baseline and DC. At an ICP of 50 mmHg, HC offers 130 mL extra space but 172 mL less than a DC. Based on local polynomial regression, the mean volume difference between HC and the standard craniotomy was 10%; 14% between DC and HC; both are higher than the volume of brain herniation reported in the literature in the clinical setting. The volume leading to an ICP of 50 mmHg at baseline was less than the volume needed to reach an ICP of 20 mmHg after HC (10.05% and 14.95% from baseline, respectively).

CONCLUSIONS

These data confirm the efficacy of HC in providing sufficient volume expansion. HC is a valid intermediate alternative in case of potentially evolutionary lesions and non-massive edema, especially in developing countries.

Hinge craniotomy as an alternative technique for patients with refractory intracranial hypertension

Introduction

Decompressive craniectomy (DC) can save brain tissue, but unfortunately it has many limitations and complications. Hinge craniotomy (HC), as less aggressive method seems to be adequate alternative not only to DC but also to conservative treatment.

Research question

Presentation of the results of modified surgical techniques of cranial decompression and comparing with more and less aggressive medical options.

Material and methods

A prospective clinical study was conducted during 86 months. Comatose patients who suffered refractory intracranial hypertension (RIH) were treated. Altogether, 137 patients have been evaluated. The final outcome of all patients in the study was evaluated after 6 months.

Results

Both surgical options resulted in adequate control of intracranial pressure (ICP). HC method was shown to have the lowest probability of worsening from a prior state of relative stability.

Discussion and conclusion

There was no statistically significant difference between methods to treatment of DC or HC, meaning the final outcome of patients treated in any manner. There was similar rate of early and late complications.

Technical Optimization of Decompressive Craniectomy for Possible Conversion to Hinge Craniotomy in Traumatic Brain Injury

Hinge craniotomy for the management of elevated intracranial pressure (ICP) in traumatic brain injury remains a technique not widely adopted. The hinged bone flap decreases the allowable intracranial volume expansion, which can lead to persistent post-operative elevated ICP and the need for salvage craniectomy. Herein, we describe the technical nuances in performing a decompressive craniectomy that, when optimized, allows for stronger consideration for hinge craniotomy as a definitive technique. To conclude, hinge craniotomy is a reasonable option in the setting of traumatic brain injury. Trauma neurosurgeons can consider the technical steps to optimize a decompressive craniectomy and perform hinge craniotomy when allowable.

How much space is needed for decompressive surgery in malignant middle cerebral artery infarction: Enabling single-stage surgery

Introduction

Decompressive hemicraniectomy (DCE) is routinely performed for intracranial pressure control after malignant middle cerebral artery (MCA) infarction. Decompressed patients are at risk of traumatic brain injury and the syndrome of the trephined until cranioplasty. Cranioplasty after DCE is itself associated with high complication rates. Single-stage surgical strategies may eliminate the need for follow-up surgery while allowing for safe brain expansion and protection from environmental factors.

Research question

Assess the volume needed for safe expansion of the brain to enable single-stage surgery.

Materials and methods

We performed a retrospective radiological and volumetric analysis of all patients that had DCE in our clinic between January 2009 and December 2018 and met inclusion criteria. We investigated prognostic parameters in perioperative imaging and assessed clinical outcome.

Results

Of 86 patients with DCE, 44 fulfilled the inclusion criteria. Median brain swelling was 75.35 mL (8.7-151.2 mL). Median bone flap volume was 113.3 mL (73.34-146.1 mL). Median brain swelling was 1.62 mm below the previous outer rim of the skull (5.3 mm to -2.19 mm). In 79.6% of the patients, the volume of removed bone alone was equivalent to or larger than the additional intracranial volume needed for brain swelling.

Discussion and conclusion

The space provided by removal of the bone alone was sufficient to match the expansion of the injured brain after malignant MCA infarction in the vast majority of our patientsA subgaleal space-expanding flap with a minimal offset can provide protection from trauma and atmospheric pressure without compromising brain expansion.

Development of a Novel Device for Decompressive Craniectomy: An Experimental and Cadaveric Study and Preliminary Clinical Application

BACKGROUND

Decompressive craniectomy is an intervention of established efficacy in patients with intractable cerebral edema.

OBJECTIVE

To evaluate a new device used in alternative to decompressive craniectomy. This device is designed to perform an augmentative craniotomy by keeping the bone flap elevated using specific cranial suspension titanium plates and giving the brain enough room to swell.

METHODS

We tested the mechanical characteristics of the cranial brackets on dried skulls, on 3D-printed skull models, and on a preserved cadaver head. The resistance of the device was examined through dynamometric testing, and the feasibility of the surgical technique, including the suspension of the bone flap and the skin closure, was investigated on the cadaveric model. A preliminary clinical series of 2 patients is also reported.

RESULTS

The laboratory tests have shown that this system allows an adequate expansion of the intracranial volume and it could withstand a force up to 637 ± 13 N in the synthetic model and up to 658 ± 9 N in the human skull without dislocation or failure of the brackets nor fractures of the bone ridges. Preliminary application in the clinical setting has shown that augmentative craniotomy is effective in the control of intracranial hypertension and could reduce the costs and complications associated with the classical decompressive craniectomy technique.

CONCLUSION

Preliminary laboratory and clinical results show augmentative craniotomy to be a promising, alternative technique to decompressive craniectomy. Further clinical studies will be needed to validate its efficacy.

Space-expanding flap in decompressive hemicraniectomy for stroke

OBJECTIVE

Decompressive hemicraniectomy (DCE) is the standard of care for space-occupying malignant infarction of the medial cerebral artery in suitable patients. After DCE, the brain is susceptible to trauma and at risk for the syndrome of the trephined. This study aimed to assess the feasibility of using temporary space-expanding flaps, implanted during DCE, to shield the brain from these risks while permitting the injured brain to expand.

METHODS

The authors performed a prospective feasibility study to analyze the safety of space-expanding flaps in 10 patients undergoing DCE and evaluated clinical and radiological outcomes.

RESULTS

The relatives of 1 patient withdrew consent, leaving 9 patients in the final analysis. No patients required removal of the space-expanding flap because of uncontrolled increase of intracranial pressure or infection. One patient required additional external ventricular drainage and 1 received mannitol. The mean (range) midline shift decreased from 6.67 (3-12) mm to 1.26 (0-2.6) mm after DCE with the space-expanding flap. The authors observed no cases of sinking skin flap syndrome, other complications, or deaths. One patient underwent further treatment due to infection of the reimplanted autologous bone flap. Two patients later refused cranioplasty, preferring to keep the space-expanding flap and thus avoid the potential risks of cranioplasty.

CONCLUSIONS

This feasibility study showed that the concurrent use of space-expanding flaps appeared to be safe in patients who underwent DCE for malignant infarction of the medial cerebral artery. Moreover, space-expanding flaps may permit patients to avoid a second surgery for reimplantation of the autologous bone flap and the risks inherent to this procedure.

The intracranial pressure-volume relationship following decompressive hinge craniotomy compared to decompressive craniectomy-a human cadaver study

OBJECTIVE

Decompressive hinge craniotomy (DHC) is an alternative treatment option to decompressive craniectomy (DC) for elevated intracranial pressure (ICP). The aim of this study was to characterize the difference in pressure-volume relationship between DHC and DC.

METHODS

We compared the intracranial pressure-volume relationship in a human cadaver model following either DHC, DC, or fixing of the bone plate by titanium clamps. We inserted an intracranial expandable device in two human cadaver specimens, performed either DHC, DC, or bone plate fixation, and gradually increased the intracranial volume while measuring ICP. Following DHC, we also performed CT-scans at pre-defined intervals.

RESULTS

Before ICP exceeded a threshold of 20 mmHg, a fixed bone plate tolerated an increase of 130 ml of intracranial volume, while DHC and DC allowed an increase of 190 ml and 290 ml, respectively. CT-derived calculations following DHC determined that the increase in intracranial volume at ICP 22 mmHg was 65 ml, the maximal increase of intracranial volume was 84 ml, the maximal bone displacement was 21 mm, and the bone plate volume to be 82 ml. Manual stress test of the hinged bone plate did not allow misalignment or intracranial displacement of the bone plate.

CONCLUSION

DHC increases the intracranial volume by up to 84 ml and allows for approximately 60 ml increase of intracranial volume before ICP exceeds 20 mmHg. This indicates, when comparing with results from previous studies of herniation volumes, that DHC will be sufficient in many patients with head injury or cerebral infarction with treatment refractory intracranial hypertension.

Dynamic Craniotomy With NuCrani Reversibly Expandable Cranial Bone Flap Fixation Plates: A Technical Report

BACKGROUND

Dynamic craniotomy provides cranial decompression without bone flap removal along with avoidance of cranioplasty and reduced risks for complications.

OBJECTIVE

To report the first clinical cases using a novel dynamic craniotomy bone flap fixation system. The NeuroVention NuCrani reversibly expandable cranial bone flap fixation plates provide dynamic bone flap movement to accommodate changes in intracranial pressure (ICP) after a craniotomy.

METHODS

The reversibly expandable cranial bone flap fixation plates were used for management of cerebral swelling in a patient with a subdural hemorrhage after severe traumatic brain injury and another patient with a hemorrhagic stroke.

RESULTS

Both cases had high ICP's which normalized immediately after the dynamic craniotomy. Progressive postoperative cerebral swelling was noted which was compensated by progressive outward bone flap migration thereby maintaining a normal ICP, and with resolution of the cerebral swelling, the plates retracted the bone flaps to an anatomic flush position.

CONCLUSION

The reversibly expandable plates provide an unhinged cranial bone flap outward migration with an increase in ICP and retract the bone flap after resolution of brain swelling while also preventing the bone flap from sinking inside the skull.

Absorbable Artificial Dura Versus Nonabsorbable Artificial Dura in Decompressive Craniectomy for Severe Traumatic Brain Injury: A Retrospective Cohort Study in Two Centers

Background

Severe traumatic brain injury (TBI) patients usually need decompressive craniectomy (DC) to decrease intracranial pressure. Duraplasty is an important step in DC with various dura substitute choices. This study aims to compare absorbable dura with nonabsorbable dura in duraplasty for severe TBI patients.

Methods

One hundred and three severe TBI patients who underwent DC and dura repair were included in this study. Thirty-nine cases used absorbable artificial dura (DuraMax) and 64 cases used nonabsorbable artificial dura (NormalGEN). Postoperative complications, mortality and Karnofsky Performance Scale (KPS) score in one year were compared in both groups.

Results

Absorbable dura group had higher complication rates in transcalvarial cerebral herniation (TCH) (43.59% in absorbable dura group vs. 17.19% in nonabsorbable dura group, P = 0.003) and CSF leakage (15.38% in absorbable dura group vs. 1.56% in nonabsorbable dura group, P = 0.021). But severity of TCH described with hernial distance and herniation volume demonstrated no difference in both groups. There was no statistically significant difference in rates of postoperative intracranial infection, hematoma progression, secondary operation, hydrocephalus, subdural hygroma and seizure in both groups. KPS score in absorbable dura group (37.95 ± 28.58) was statistically higher than nonabsorbable dura group (49.05 ± 24.85) in one year after operation (P = 0.040), while no difference was found in the rate of functional independence (KPS ≥ 70). Besides, among all patients in this study, TCH patients had a higher mortality rate (P = 0.008), lower KPS scores (P < 0.001) and lower functionally independent rate (P = 0.049) in one year after surgery than patients without TCH.

Conclusions

In terms of artificial biological dura, nonabsorbable dura is superior to absorbable dura in treatment of severe TBI patients with DC. Suturable nonabsorbable dura has fewer complications of TCH and CFS leakage, and manifest lower mortality and better prognosis. Postoperative TCH is an important complication in severe TBI which usually leads to a poor prognosis.

Hemicraniectomy and externalized ventricular drain placement in a pediatric patient with myelin oligodendrocyte glycoprotein-associated tumefactive demyelinating disease

BACKGROUND

Acquired demyelination of the central nervous system in children can manifest as multiple sclerosis, neuromyelitis optica, myelin oligodendrocyte glycoprotein (MOG)-associated demyelination, or as an acute monophasic illness without serum antibodies. Rarely do patients with demyelinating disease need surgical intervention for fulminant crises.

CASE

We report a case of anti-MOG antibody-related tumefactive demyelination in a 10-year-old female who required urgent hemicraniectomy and external ventricular drain placement for progressive white matter edema with obstructive hydrocephalus, subfalcine, and transtentorial herniation.

When the Bone Flap Expands Like Bellows of Accordion: Feasibility Study Using Novel Technique of Expansile (Hinge) Craniotomy for Severe Traumatic Brain Injury

Background

Decompressive craniectomy (DC) is a rescue operation performed for reduction of intracranial pressure due to progressive brain swelling, mandating the need for cranioplasty.

Objective

To describe expansile craniotomy (EC) as a noninferior technique that may be effectively utilized in situations requiring standard DC.

Materials and Methods

A decision to perform DC or EC was taken by consecutively allocation to either of the procedures. The bone flap was divided into three pieces, which were tied loosely to each other and to the skull using silk threads. The primary outcome included functional assessment using Glasgow outcome scale (GOS) score at 1 year.

Results and Conclusions

Total 67 patients were included in the analyses, of which, 31 underwent EC and 36 underwent DC. Both the cohorts were matched in terms of baseline determinants for age, Glasgow coma scale, and Rotterdam score at admission. There was no significant difference in GOS scores and the extent of volume expansion obtained by EC as compared to DC. Complication rates though less in EC group did not differ significantly between the groups. EC appears to be the safe and effective alternative to DC in the management of brain swelling due to TBI with a potential to obviate the need of cranioplasty.

Decompressive craniotomy: an international survey of practice

BACKGROUND

Traumatic brain injury (TBI) and stroke have devastating consequences and are major global public health issues. For patients that require a cerebral decompression after suffering a TBI or stroke, a decompressive craniectomy (DC) is the most commonly performed operation. However, retrospective non-randomized studies suggest that a decompressive craniotomy (DCO; also known as hinge or floating craniotomy), where a bone flap is replaced but not rigidly fixed, has comparable outcomes to DC. The primary aim of this project was to understand the current extent of usage of DC and DCO for TBI and stroke worldwide.

METHOD

A questionnaire was designed and disseminated globally via emailing lists and social media to practicing neurosurgeons between June and November 2019.

RESULTS

We received 208 responses from 60 countries [40 low- and middle-income countries (LMICs)]. DC is used more frequently than DCO, however, about one-quarter of respondents are using a DCO in more than 25% of their patients. The three top indications for a DCO were an acute subdural hematoma (ASDH) and a GCS of 9-12, ASDH with contusions and a GCS of 3-8, and ASDH with contusions and a GCS of 9-12. There were 8 DCO techniques used with the majority (60/125) loosely tying sutures to the bone flap. The majority (82%) stated that they were interested in collaborating on a randomized trial of DCO vs. DC.

CONCLUSION

Our results show that DCO is a procedure carried out for TBI and stroke, especially in LMICs, and most commonly for an ASDH. The majority of the respondents were interested in collaborating on a is a future randomized trial.

Three-pillar expansive craniotomy: a new surgical technique for cerebral decompression in children

PURPOSE

The aim of this study is to conduct a retrospective review of data obtained in all consecutive patients who had undergone cerebral decompression using the 3-pillar expansive craniotomy (3PEC) in our hospital between 2016 and 2020.

METHODS AND RESULTS

We developed a novel craniotomy technique using expansion cranioplasty in patients with traumatic brain injury or stroke, which could relieve intracranial hypertension, maintain cerebral protection, and avoid subsequent cranial repair. Sixteen patients aged 2-18 years old underwent the 3PEC. Two patients, who presented very severe neurological conditions at the admission, died. All surviving patients showed good neurological outcome. None of the survived patients presented with bone flap resorption or sinking flap syndrome.

CONCLUSION

The role of decompressive craniectomy has been recently questioned in the pediatric population by the use of decompressive craniotomy. In this limited study of children patients experiencing stroke or traumatic brain injury, 3PEC was proved useful in reducing intracranial pressure (ICP), thus, questioning the role of decompressive craniectomy in children. The technique effectively reduces postoperative complications and eliminates subsequent cranioplasty procedures otherwise introduced by traditional decompressive craniectomy.

Split-Thickness Decompression in the Management of Intracranial Pressure

Surgical management of elevated intracranial pressures due to stroke or traumatic brain injury has classically been through decompressive craniectomy (DC). There is significant morbidity associated with DC including subdural hygromas, syndrome of the trephined, and the need for subsequent cranioplasty. Alternative techniques including the hinged and floating craniotomy have shown promise though can still suffer from complications associated with an unsecured bone flap. We report a case in which a patient who presented with an acute subdural hematoma and associated midline shift that was successfully treated with decompression via thinning and re-securing of the bone flap in a “split-thickness decompression.”

Hinge and floating decompressive craniotomy for infantile acute subdural hematoma: technical note

Cranioplasty complications after decompressive craniectomy (DC) in infants are not fully recognized. We aimed to devise and assess the efficacy of a hinge and floating DC (HFDC) technique for treating infantile acute subdural hematoma. Five infants, aged 2-20 months, were included. Intracranial pressure was controlled below 20 mmHg, no additional surgery was required, and there was no incidence of surgical site infection or bone graft resorption.

Long-term follow-up of custom-made porous hydroxyapatite cranioplasty in adult patients: a multicenter European study. Can we trust self-reported complications?

BACKGROUND

Cranioplasty is a surgical intervention aiming to re-establish the integrity of skull defects. Autologous bone and different heterologous materials are used for this purpose, with various reported related complications. The aim of the study was to evaluate the complication rate in a multicentric cohort of patients underwent porous hydroxyapatite (PHA) cranioplasty implantation and to assess the validity of company post-market clinical analysis.

METHODS

Authors analyzed a company based register of 6279 PHA cranioplasty implanted all over the world. In these adult patients only self-reported complications were available. We then obtained the data of adult patients treated with custom-made porous HA prostheses (CustomBone Service) in 20 institutions from different European countries through an on-site interview with the physicians in charge of the patients (494 patients). The endpoints were the incidence of adverse events and of related implant removal.

RESULTS

The groups of patients had similar demographics characteristics. The average follow-up was 26.7 months. A significantly higher number of complications was recorded in the group of patients underwent onsite interview. Thirty-nine complications were reported (7.89%) with an explantation rate of 4.25% (21 cases) in the series, compared to the data reported from the Company (complications rate of 3.3% and explantation rate of 3.1%). The most common complications were infection (4.86%), hematomas (1.22%), fractures (1.01%), mobilization (0.4%) and scar retraction (0.4%).

CONCLUSIONS

Our data confirm that porous HA cranioplasty is at least as effective as other heterologous materials to repair cranial defects. Another interesting finding is that self-reporting complicantions by surgeons does not give a precise picture of the real rate of complications of the devices. These data in future studies need to be re-confirmed with on-site interviews.