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

Decompressive Craniectomy and Hinged Craniotomy for Traumatic Brain Injury: Experience in Two Centers in a Middle-Income Country

Objective

The goal of a decompressive craniectomy (DC) or a hinge craniotomy (HC), is to treat intracranial hypertension and reduce mortality. Traditionally, the decompression procedure has been performed with cranial bone removal. However, decompression and repositioning the cranial bone, named HC, has been presented as an alternative for certain cases. Our objective is to describe the neuroradiological and clinical preoperative factors and outcomes in traumatic brain injury (TBI) cases treated with both techniques in 2 centers in a Middle-Income country.

Methods

This is a retrospective cross-sectional study of adult patients who underwent decompression surgical treatment for TBI, either with a traditional DC or HC, in 2 centers in Bogotá, Colombia between 2016-2020.

Results

This study involved 30 cases that underwent HC and 20 that underwent DC. 78% were male with an overall mean age of 50.2 years. 66% cases had traumatic subarachnoid hemorrhage (tSAH) and 60% had evidence of acute subdural hematoma ≥10 mm in thickness. The overall mortality rate during hospitalization was 20%. Preoperative pupil impairment differences between the 2 groups were statistically significant (p=0.026).

Conclusion

This study reveals that using a traditional DC or HC depends on the neurosurgeon's intraoperative case-by-case assessment according to the intraoperative brain's vitality and the presence of diffuse edema in the brain parenchyma at the time of surgical closure. Each case requires an individualized evaluation before and during surgery. The preoperative pupil condition can serve as a marker for HC or DC selection.

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.

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.

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.