A systematic review and meta-analysis of major blood protein biomarkers that predict unfavorable outcomes in severe traumatic brain injury

INTRODUCTION

Severe traumatic brain injury (TBI) presentation and late clinical outcomes are usually evaluated by the Glasgow Outcome Scale-Extended (GOS-E), which lacks strong prognostic predictability. Several blood biomarkers have been linked to TBI, such as Tau, GFAP, UCH-L1, S-100B, and NSE. Clinical values of TBI biomarkers have yet to be evaluated in a focused multi-study meta-analysis. We reviewed relevant articles evaluating potential relationships between TBI biomarkers and both early and 6-month outcomes.

METHODS

All PubMed article publications from January 2000 to November 2023 with the search criteria "Protein Biomarker" AND "Traumatic Brain Injury" were included. Amongst all comparative studies, the sensitivity means and range values of biomarkers in predicting CT Rotterdam scores, ICU admission in the early period, or predicting GOS-E < 4 at the 6-month period were calculated from confusion matrices. Sensitivity values were modeled for each biomarker across studies and compared statistically for heterogeneity and differences.

RESULTS

From the 65 articles that met the criteria, 13 were included in this study. Six articles involved early-period TBI outcomes and seven involved 6-month outcomes. In the early period TBI outcomes, GFAP had a superior sensitivity to UCH-L1 and S-100B, and similar sensitivity to the CT Rotterdam score. In the 6-month period TBI outcomes, total Tau and NSE both had significant interstudy heterogeneity, making them inferior to GFAP, phosphorylated Tau, UCH-L1, and S-100B, all four of which had similar sensitivities at 75 %. This sensitivity range at 6-month outcomes was still relatively inferior to the CT Rotterdam score. Total Tau did not show any prognostic advantage at six months with GOS-E < 4, and phosphorylated Tau was similar in its sensitivity to other biomarkers such as GFAP and UCH-L1 and still inferior to the CT Rotterdam score.

CONCLUSION

This data suggests that TBI protein biomarkers do not possess better prognostic value with regards to outcomes.

Arteriovenous malformation presenting as complex regional pain syndrome: illustrative case

BACKGROUND

Complex regional pain syndrome (CRPS) is typically described as a peripheral nerve disorder in which exaggerated allodynia and hyperalgesia follow a minor injury. Some researchers propose a central mechanism, although current evidence is lacking.

OBSERVATIONS

A 14-year-old female presented with classic CRPS symptoms of left upper-extremity weakness and hyperalgesia after a bout of sharp pain in her thumb while shoveling snow. A possible seizure prompted magnetic resonance imaging, revealing a right frontal Spetzler-Martin grade II arteriovenous malformation (AVM) adjacent to the primary motor cortex. Brodmann areas 1, 3a, and 3b, which are responsible for localizing and processing burning and painful sensations, were also involved. The patient underwent transarterial Onyx embolization in two sessions and microsurgical resection, after which her CRPS symptoms completely resolved.

LESSONS

To our knowledge, this is the first reported case of a cerebral AVM presenting as CRPS, which supports a central mechanism. The authors propose that rapid growth of the AVM led to a vascular steal phenomenon of surrounding parenchyma, which disrupted the patient's normal motor function and nociceptive processing. Further validation in other series is needed.

Acquired Chiari Type I Malformation Associated with Type IV Dural Arteriovenous Fistula: Case Report

BACKGROUND

 Chiari malformations, usually congenital, can rarely be associated with arteriovenous (AV) fistulas. We present the first case involving a type IV dural AV fistula with a Chiari type I malformation.

METHODS

 Retrospective chart review was performed to obtain pertinent details regarding history and examination, pathologic findings, and treatment course.

RESULTS

 A 63-year-old woman with a 2-year history of migraines presented with 5 months of occipital, right-sided headaches and neck pain exacerbated by Valsalva maneuvers. Computed tomography (CT) and magnetic resonance imaging (MRI) of the head showed a possible right occipital AV malformation, bilateral cerebellar subdural hygromas, and tonsillar crowding at the foramen magnum indicating an acquired Chiari type I malformation. Angiography demonstrated a Cognardtype IV right posterior occipital dural AV fistula supplied by bilateral middle meningeal and posterior meningeal arteries.

CONCLUSION

 After treatment of the dural AV fistula, hygroma evacuation, and decompression of the acquired Chiari malformation, the patient's Valsalva-induced headaches abated.

Single-Session Gamma Knife Radiosurgery for Patients With 20 or More Brain Metastases

BACKGROUND

Stereotactic radiosurgery (SRS) is a widely accepted treatment modality for brain metastases. The role of SRS in patients with higher numbers of metastases remains controversial.

OBJECTIVES

To define outcomes in patients with ≥20 brain metastases managed using single-session SRS.

METHODS

This single-institution retrospective cohort study studied 75 patients (26 non-small-cell lung cancer, 21 small-cell lung cancer, 14 breast cancer, and 14 melanoma) undergoing single-session SRS. The median number of tumors per patient was 24, and the median cumulative tumor volume was 3.70 cc. The median margin dose prescribed to each individual tumor was 16 Gy. The median integral cranial dose was 5492 mJ. The median beam on time was 160 minutes. Univariate and multivariate analyses were performed with significance set at P < .05.

RESULTS

The median overall survival after SRS was 8.8 months (patients with non-small-cell lung cancer), 4.6 months (patients with small-cell lung cancer), 11.3 months (patients with breast cancer), and 4.1 months (patients with melanoma). Primary cancer type, number of brain metastases, and concurrent immunotherapy were significant factors in predicting survival. Local tumor control rate per patient was 97.3% and 94.6% at 6 and 12 months after SRS, respectively. Thirty-six patients underwent additional SRS for new tumor development with a median time after SRS of 5 months. Three patients experienced adverse radiation events.

CONCLUSION

Single-session SRS is a well-tolerated palliative treatment option even in patients with ≥20 brain metastases, achieving local control rate >90% with low risks of neurotoxicity while continuing concurrent systemic oncological care.

Gamma Knife radiosurgery for gynecologic metastases to the brain: Analysis of pathology, survival, and tumor control

OBJECTIVE

This study aims to evaluate the efficacy of stereotactic radiosurgery (SRS) in improving health outcomes of patients with gynecologic brain metastases.

METHODS

Patients with gynecologic metastases treated with SRS from 2008 to 2020 were retrospectively reviewed. The median age at SRS was 63 years old (cervical 45.5, endometrial 65.5, ovarian 61). The median number of tumors was 3 (range 1-27), and cumulative tumor volume was 2.33 cc (range 0.03-45.63). Median margin dose prescribed was 16 Gy (range 14 Gy - 20 Gy). The median 12 Gy volume was 7.30 cc (range 0.21-74.14 cc). Outcome variables included overall survival (OS) after SRS, local tumor control (LTC), distant tumor control, and adverse radiation effect (ARE).

RESULTS

Fifty patients (4 cervical, 25 endometrial, and 21 ovarian cancer) were identified. The OS at 6 and 12 months after SRS was 48%, and 44%, respectively. Eight patients (16%) died from CNS disease progression. The number of brain metastases (p = 0.011) and the Karnofsky Performance Scale (KPS) ≥ 70 (p = 0.020) were significant predictors of OS. LTC rate at 6 and 12 months were 92%, and 87%, respectively. Margin dose ≥16Gy correlated with significantly better local tumor control (p = 0.0001) without increased risk of ARE (p = 0.055). The risk of developing new metastases at 6 and 12 months were 12% and 24% respectively. SRS-induced ARE events occurred in 7 patients.

CONCLUSION

Intracranial metastases from gynecologic malignancy can be effectively treated using SRS with low risk of neurotoxicity. Margin dose ≥16Gy can provide significantly better tumor control. Repeat SRS can be utilized to treat new metastases while avoiding the potential cognitive symptoms associated with WBRT.

Stereotactic radiosurgery as the initial management option for small-volume hypothalamic hamartomas with intractable epilepsy: a 35-year institutional experience and systematic review

OBJECTIVE

Young patients with hypothalamic hamartomas (HHs) often present with intractable epilepsy. Currently there are no established management guidelines for HH. The authors retrospectively reviewed their single-institution experience to delineate the role of stereotactic radiosurgery (SRS).

METHODS

Seven patients with HHs (4 females; median age 13.7 years, range 2.5-25 years) with no prior resection underwent SRS between 1987 and 2022. The clinical history, epilepsy profile, radiographic findings, and neurological outcomes were characterized. HH topographical types were classified according to the Régis classification. Outcome measures included Engel seizure classification, HH response, and the need for additional surgical interventions.

RESULTS

All patients had Engel class IV epilepsy. A Leksell Gamma Knife was used to deliver a median margin dose of 18 Gy (range 16-20 Gy) to a median hamartoma volume of 0.37 cm3 (range 0.20-0.89 cm3). Seizure reduction was confirmed in 6 patients, and 2 patients had regression of their hamartoma. Two patients underwent resection and/or laser interstitial thermal therapy after SRS. At follow-up, 1 patient was seizure free, 4 patients achieved Engel class II, 1 patient had Engel class III, and 1 patient had Engel class IV seizure outcomes.

CONCLUSIONS

SRS as the initial management option for HH was associated with a low risk of adverse effects. In this institutional series reviewing small-volume HHs treated with SRS, no adverse radiation effect was detected, and the majority of patients experienced seizure reduction. SRS should be considered as the first-line treatment for seizure control in patients with small-volume HHs.

Critical care for concomitant severe traumatic brain injury and acute spinal cord injury in the polytrauma patient: illustrative case

BACKGROUND

The occurrence of traumatic brain injury with spinal cord injury (SCI) in polytrauma patients is associated with significant morbidity. Clinicians face challenges from a decision-making and rehabilitative perspective. Management is complex and understudied. Treatment should be systematic beginning at the scene, focusing on airway resuscitation and hemodynamic stabilization, immobilization, and timely transport. Early operative interventions should be provided, followed by minimizing secondary pathophysiology. The authors present a case to delineate decision-making in the treatment of combined cranial and spinal trauma.

OBSERVATIONS

A 19-year-old man presented as a level I trauma patient after falling 30 feet as the result of scaffolding collapse. The patient was unresponsive and was intubated; he had an initial Glasgow Coma Scale score of 4. Computed tomography revealed multicompartmental bleeding and herniation, for which supra- and infratentorial decompressive craniectomies were performed. The patient also suffered from thoracic SCI that resulted in complete paraplegia. Multimodality monitoring was used. After stabilization and lengthy rehabilitation, the patient obtained significant functional improvement.

LESSONS

The approach to initial management of concomitant head and spine trauma is to establish intracranial stability followed by intraspinal stability. Patients can make considerable recovery, particularly younger patients, who are more likely to benefit from early aggressive interventions and medical treatment.

Stereotactic Electroencephalography Implantation Through Nonautologous Cranioplasty: Proof of Concept

BACKGROUND

Stereoelectroencephalography (SEEG) is an effective method to define the epileptogenic zone (EZ) in patients with medically intractable epilepsy. Typical placement requires passing and anchoring electrodes through native skull.

OBJECTIVE

To describe the successful placement of SEEG electrodes in patients without native bone. To the best of our knowledge, the use of SEEG in patients with nonautologous cranioplasties has not been described.

METHODS

We describe 3 cases in which SEEG was performed through nonautologous cranioplasty. The first is a 30-yr-old male with a titanium mesh cranioplasty following a left pterional craniotomy for aneurysm clipping. The second is a 51-yr-old female who previously underwent lesionectomy of a ganglioglioma with mesh cranioplasty and subsequent recurrence of her seizures. The third is a 31-yr-old male with a polyether ether ketone cranioplasty following decompressive hemicraniectomy for trauma.

RESULTS

SEEG was performed successfully in all three cases without intraoperative difficulties or complications and with excellent electroencephalogram recording and optimal localization of the seizure focus. The EZ was successfully localized in all three patients. There were no limitations related to drilling or inserting the guiding bolt/electrode through the nonautologous cranioplasties.

CONCLUSION

SEEG through nonautologous cranioplasties was clinically feasible, safe, and effective in our series. The presence of nonautologous bone cranioplasty should not preclude such patients from undergoing SEEG explorations.

Chronicling the philanthropic arm of neurological surgery: a review of the growth and development of the Neurosurgery Research & Education Foundation

OBJECTIVE

The Neurosurgery Research & Education Foundation (NREF), previously known as the Research Foundation of the American Association of Neurological Surgeons (AANS), was established in 1980 to encourage and facilitate innovation through financial support to young neurosurgeons in the process of honing their competencies in neurosciences and neurological surgery. This article provides a historical overview of NREF, its mission, and charitable contributions and the ever-expanding avenues for neurosurgeons, neurosurgical residents and fellows, and medical students to supplement clinical training and to further neurosurgical research advances.

METHODS

Data were collected from the historical archives of the AANS and NREF website. Available data included tabulated revenue, geographic and institutional records of funding, changes in funding for fellowships and awards, advertising methods, and sources of funding.

RESULTS

Since 1984, NREF has invested more than $23 million into the future of neurosurgery. To date, NREF has provided more than 500 fellowship opportunities which have funded neurosurgeons' education and research efforts at all stages of training and practice.

CONCLUSIONS

NREF is designed to serve as the vehicle through which the neurosurgical community fosters the continued excellence in the care of patients with neurosurgical diseases.

A History of the Lobes of the Brain

The division of the cerebrum into 5 lobes is widely accepted in the scientific community. Despite this, a history of the lobes of the brain has not been discussed in the literature. Therefore, this article recounts this history with emphasis on the contributions of Thomas Willis (1664), Felix Vicq d'Azyr (1796), Johann-Christian Reil (1796), François Chaussier (1807), and Louis Pierre Gratiolet and François Leuret (1857) into one of the most widely accepted concepts in neuroanatomy.

Routine repeat head CT may not be necessary for patients with mild TBI

Background

Routine repeat cranial CT (RHCT) is standard of care for CT-verified traumatic brain injury (TBI). Despite mixed evidence, those with mild TBI are subject to radiation and expense from serial CT scans. Thus, we investigated the necessity and utility of RHCT for patients with mild TBI. We hypothesized that repeat head CT in these patients would not alter patient care or outcomes.

Methods

We retrospectively studied patients suffering from mild TBI (Glasgow Coma Scale (GCS) score 13–15) and treated at the R Adams Cowley Shock Trauma Center from November 2014 through January 2015. The primary outcome was the need for surgical intervention. Outcomes were compared using paired Student’s t-test, and stratified by injury on initial CT, GCS change, demographics, and presenting vital signs (mean ± SD).

Results

Eighty-five patients met inclusion criteria with an average initial GCS score=14.6±0.57. Our center sees about 2800 patients with TBI per year, or about 230 per month. This includes patients with concussions. This sample represents about 30% of patients with TBI seen during the study period. Ten patients required operation (four based on initial CT and others for worsening GCS, headaches, large unresolving injury). There was progression of injury on repeat CT scan in only two patients that required operation, and this accompanied clinical deterioration. The mean brain Abbreviated Injury Scale (AIS) score was 4.8±0.3 for surgical patients on initial CT scan compared with 3.4±0.6 (P<0.001) for non-surgical patients. Initial CT subdural hematoma size was 1.1±0.6 cm for surgical patients compared with 0.49±0.3 cm (P=0.05) for non-surgical patients. There was no significant difference between intervention groups in terms of other intracranial injuries, demographics, vital signs, or change in GCS. Overall, 75 patients that did not require surgical intervention received RHCT. At $340 per CT, $51 000 was spent on unnecessary imaging ($367 000/year, extrapolated).

Discussion

In an environment of increased scrutiny on healthcare expenditures, it is necessary to question dogma and eliminate unnecessary cost. Our data questions the use of routine repeat head CT scans in every patient with anatomic TBI and suggests that clinically stable patients with small injury can simply be followed clinically.

Level of evidence

Level III.