Correlation of vascular endothelial growth factor with magnetic resonance imaging in chronic subdural hematomas

Diffusion-weighted imaging findings predictive of postoperative recurrence of chronic subdural hematoma

OBJECTIVES

To identify the brain magnetic resonance imaging (MRI) findings associated with the postoperative recurrence of chronic subdural hematoma (CSDH).

METHODS

We examined 1099 consecutive patients admitted to our hospital with CSDH between 2005 and 2014. Of those, 1021 who underwent surgery for CSDH and were followed-up for >3 months after surgery were included. Preoperative brain MRI findings were classified as homogeneous, laminar, separate, or trabecular, according to the nature of the hematoma. Postoperative recurrence was defined in patients who required reoperation for ipsilateral hematoma growth within three months of surgery. The clinical and radiological factors associated with postoperative recurrence were evaluated using univariate and multivariate analyses.

RESULTS

Of the 1021 CSDH patients with CSDH who underwent surgery, 91 (8.9%) experienced postoperative recurrence. Postoperative recurrence was significantly associated with male sex (p = 0.0004) and hematoma volume (p < 0.0001). Additionally, isotype or separate types of hematoma on computed tomography (CT) (p < 0.0001) and laminar/separate types of hematoma types on MRI (p = 0.0008) were significant. Multivariate analysis revealed odds ratios of 2.50 (95% CI, 1.45-4.61; p = 0.0007) for male sex and 3.05 (95% CI, 1.95-4.87; p < 0.0001) for iso/separate hematoma types in CT. Conversely, among the patients who underwent MRI, multivariate analysis revealed odds ratios of 4.33 (95% CI, 1.20-27.92; p = 0.001) for male sex and 4.88 (95% CI, 1.90-14.18; p = 0.023) for laminar/separate hematoma types.

CONCLUSION

While distinguishing the nature of hematomas is challenging with brain CT examination, detailed laminar/trabecular differentiation using MRI images may predict postoperative recurrence.

Prediction of Postoperative Recurrence of Chronic Subdural Hematoma Using Preoperative Systemic Immune Inflammation Index and Eosinophils

Objective  Chronic subdural hematoma (CSDH) is a common neurological problem with significant recurrence after surgery. Risk considerations can vary, ranging from patient-related factors to those related to the surgical procedure. This study explores the association between preoperative eosinophil count and systemic immune inflammation (SII) with CSDH recurrence. Materials and Methods  We conducted a prospective analysis of 105 patients with equal numbers of CSDHs who underwent surgery for CSDH between January 2023 and January 2024. The preoperative eosinophil counts, along with other differential leukocyte counts, were measured. The SII index was calculated using the standard formula (SII = neutrophil count  ×  platelet count/lymphocyte count). Multivariate and univariate regression analyses were performed to assess the association between risk factors and CSDH recurrence. Results  The preoperative eosinophil count showed a significant correlation with recurrence ( p  < 0.001). The SII index was significantly higher in patients with recurrent CSDH ( p  = 0.003). Neutrophils were found to be significantly associated with CSDH recurrence ( p  = 0.038). Age ( p  < 0.001) and SII ( p  = 0.005) were found to be independent predictors of CSDH recurrence, whereas hematoma volume ( p  < 0.001) and the antiplatelet regimen were a significant predictor of CSDH recurrence ( p  = 0.047). Variables like male gender, diabetes mellitus, anticoagulants, and hematoma volume were associated with eosinophil-rich or eosinophil-poor status. Conclusion  Preoperative eosinophil count, neutrophils, and the SII index may serve as potential predictors of CSDH recurrence. Further studies with larger sample sizes are needed to validate these findings.

Chronic subdural hematoma: What precisely are we treating?

Subdural hematoma (SDH) refers to the collection of blood between the dura matter and the arachnoid membrane. Advancements in imaging technology have enabled the categorization of SDH based on specific imaging characteristics, causative factors, and the onset of symptoms. Given that the prognosis of SDHs varies significantly and is contingent upon the size and chronicity of the hemorrhage, a comprehensive understanding of its subtypes may carry crucial treatment implications. For example, an acute SDH classically results from severe traumatic brain injury and appears as a homogenous, crescent-shaped hyperdense extra-axial collection. If not treated, over the course of 1-3 weeks, this hematoma will evolve into a sub-acute phenotype as a consequence of subdural effusion and demonstrate mixed-density hemorrhage on imaging. Chronic SDH (cSDH) becomes the end result of an untreated SDH, with neo-membranization and neo-angiogenesis from branches of the middle meningeal artery driving a mass-like growth pattern. This review article aims to elucidate the complex anatomical features of the end-stage cSDH, with a particular focus on reconceptualization of this entity based on its mass-like growth patterns, and how this is driving a shift towards endovascular treatment.

Preoperative elevated eosinophils in peripheral blood for prediction of postoperative recurrence of chronic subdural hematoma

OBJECTIVE

Chronic subdural hematoma (CSDH) is a common neurological disease with a significant postoperative recurrence rate. There are numerous reported studies of the development of CSDH. In recent years, fibrinolysis, angiogenesis, and inflammation have all been identified as relevant factors in the development of CSDH. While several authors have reported risk factors associated with CSDH recurrence, differential blood count of leukocytes has not yet been discussed. Therefore, in this study the authors aimed to retrospectively investigate the association between differential blood leukocyte count and the rate of CSDH recurrence.

METHODS

The authors retrospectively reviewed 476 patients with 529 CSDHs who underwent surgery at a single institution between January 2011 and December 2021. After exclusion of patients who had not undergone a differential blood test of leukocytes preoperatively, CSDHs in 517 cerebral hemispheres of 466 patients were included in the study. Peripheral blood eosinophil counts ≥ 100/µL were considered eosinophil rich.

RESULTS

CSDHs in 494 cerebral hemispheres of 445 patients were followed up postoperatively for at least 3 months or until resolution indicated by CSDH disappearance. Postoperative recurrence of CSDH was observed in 46 cerebral hemispheres (9.3%). Among the preoperative differential blood counts of all leukocytes, eosinophils alone were significantly associated with CSDH recurrence (median [IQR] 76/µL [30-155/µL] vs 119/µL [39-217/µL]; p = 0.03). Multivariable regression analysis showed thrombocytopenia (adjusted OR [aOR] 5.23, 95% CI 1.85-14.79; p = 0.002), use of anticoagulant drugs (aOR 2.51, 95% CI 1.17-5.38; p = 0.02), hematoma volume (10 mL per increase) (aOR 1.08, 95% CI 1.00-1.16; p = 0.04), and eosinophil-rich peripheral blood (aOR 2.22, 95% CI 1.17-4.23; p = 0.02) were all independent predictors for CSDH recurrence.

CONCLUSIONS

This study showed that preoperative peripheral blood eosinophil count was an independent risk factor for CSDH recurrence. Therefore, patients with CSDH who have elevated eosinophils preoperatively in peripheral blood require careful follow-up.

Angiogenetic Factors in Chronic Subdural Hematoma Development

The levels of angiogenic factors were analyzed in eight patients who underwent the embolization of chronic subdural hematoma (CSDH) with non-adhesive liquid embolic agents. Four of these patients had previously undergone surgical treatment for hematoma removal and had recurrences of a similar volume, and four had an increase in hematoma volume due to rebleeding. The levels of vascular endothelial growth factor (VEGF), matrix metallopeptidase 9 (MMP 9), angiopoietin-2 (Ang2), transforming growth factor beta 1 (TGF-β1) and platelet-derived growth factor BB (PDGF-BB) in the arterial and venous blood were analyzed. The most significant results were obtained from the peripheral venous blood samples. The levels of VEGF in the samples of all the patients were close to normal or slightly decreased. There was an increase in the MMP9 levels (the factor that contributes to the disintegration of the vessel wall components) in all the patients. The Ang2 and especially the PDGF TGF-β1 (the factor that plays an important role in the growth of the vessel wall from the already existing blood vessel tissue) levels were distinctly low in most of the cases and slightly elevated only in a number of patients who had previously been operated on. The results obtained show that there is an imbalance in the angiogenesis factors in patients with rebleeding CSDH. At the same time, the factors determining the formation of the vessel wall were reduced, and the levels of factors contributing to the degradation of extracellular matrix components were significantly increased. Such factors could help us to anticipate the increased risk of hemorrhages. Highlights: The levels of VEGF, MMP 9, Ang2, TGF-β1 and PDGF-BB in the arterial and venous blood were analyzed. The most significant results were obtained from the peripheral venous blood samples. The results obtained show that there is an imbalance in the angiogenesis factors in patients with rebleeding CSDH. Such a profile of factors could help us to anticipate the increased risk of hemorrhages.

MRI appearance of chronic subdural hematoma

Objective

We aimed to describe the magnetic resonance imaging (MRI) characteristics of chronic subdural hematoma (cSDH) and to ascribe MRI patterns.

Methods

A total of 20 patients having 27 subdural hematomas underwent contrast-enhanced (CE) MRI of the brain at our institution between April 2019 and May 2021. The images were independently evaluated by two experienced neuroradiologists with regard to imaging characteristics on T1w, T2w, T2*-GRE, FLAIR, diffusion-weighted magnetic resonance imaging (DWI), and CE images.

Results

The signal characteristics of cSDH on T1- and T2-weighted images were rather heterogeneous. The majority of hematomas (74%) had internal septations. Surprisingly, contrast enhancement along the outer membrane adjacent to the cranium was noticed in all hematomas. There was also contrast enhancement along the inner membrane adjacent to the brain in more than one-third of the hematomas (37%). In approximately two-thirds of the cSDH (62%), there was a mass-like enhancement of the hematoma. Most hematomas (89%) were partially hypointense on T2*-GRE and/or susceptibility-weighted imaging (SWI). Restricted diffusion was detected in approximately one-third of the hematomas (33%).

Conclusion

Consistent contrast enhancement along the outer membrane, triangular-shaped contrast enhancement at the borders of the cSDH, and infrequent enhancement of the inner membrane may help to distinguish cSDH from other entities such as empyema and tumors. Mass-like enhancement may refer to non-solid hematomas and could be an indicator for hematoma growth and a possible surrogate for successful endovascular embolization. Restricted diffusion in a subdural mass is not specific for empyema but may also be found in cSDH.

Adjunctive postoperative course of dexamethasone in chronic subdural hematoma: Effect on surgical outcome

Objectives:

To compare the effect of burrhole craniostomy with and without a postoperative course of dexamethasone on recurrence rate of chronic subdural hematoma (CSDH).

Methods:

The study was conducted at the Department of Neurosurgery, Pakistan Institute of Medical Sciences, Islamabad, from September 2017 till May 2018. Adult patients diagnosed with CSDH and advised burrhole craniostomy were enrolled in this prospective randomized controlled trial. Participants were randomized into Group-1 (receiving two weeks dexamethasone), and Group-2 (no dexamethasone). Clinical assessment and Brain CT were done preoperatively, second postoperative day, sixth and twelfth postoperative week, with outcome assessed at twelfth postoperative week. Complications of treatment and recurrence rate were recorded.

Results:

Ninety-two (n=92, 46 in each group) patients were enrolled. Improvement in neurological (95.7% vs 93.5%; P=0.646) and radiological outcome (95.7% vs 93.5%; P=0.646) was similar in both groups. Complication rate was higher in Group-1 but not significantly different (58.7% vs 43.5%; P=0.535). Most frequent complication was pneumocephalus, with mortality rate equal (n=one). Recurrence was observed in 2.2% (n=1/46) patients in Group-1 and 4.3% (n=2/46) in Group-2 (P=0.557), which was not statistically significant.

Conclusions:

Neurological and radiological outcome, and mortality rates were similar in both groups. The recurrence rate was lower and complications slightly higher in Group-1 but these were not statistically significant.

History and current progress of chronic subdural hematoma

Chronic subdural hematoma (CSDH) is characterized by an encapsulated collection of old blood. Although CSDH has become the most frequent pathologic entity in daily neurosurgical practice, there are some unresolved research questions. In particular, the causes and recurrent risk factors of CSDH remain as an object of debate. The split of the dural border layer forms a few tiers of dural border cells over the arachnoid layer. Tissue plasminogen activator plays an important role as a key factor of defective coagulation. Historically, CSDH has often been treated via burr hole craniostomy using a closed drainage system. Several different operative strategies and peri-operative strategies such as the addition of burr holes, addition of cavity irrigation, position of drain, or postural position, have been described previously. Although the direction of the drainage tube, residual air, low intensity of T1-weighted images on MRI, and niveau formation have been reported as risk factors for recurrence, antiplatelet or anticoagulant drug use has not yet been verified as a risk factor. Recently, pharmaceutical strategies, including atorvastatin, significantly improved the neurological function in CSDH patients. Many case series, without randomization, have been reported; and given its promising result, several randomized clinical trials using pharmaceutical as well as operative and perioperative strategies were initiated to obtain sufficient data. In contrast, relatively fewer basic studies have achieved clinical applications in CSDH, although it is one of the most common clinical entities. Further scientific basic research may be essential for achieving a novel treatment strategy for CSDH.

Dexamethasone enhances the efficacy of atorvastatin in inhibiting excessively inflammation-induced abnormal angiogenesis by regulating macrophages

BACKGROUND

We have recently showed that atorvastatin (ATO) combined with low dose of dexamethasone (DEX) was more efficacious in treating patients with chronic subdural haematoma (CSDH) than ATO monotherapy. This study was designed to investigate the underlying mechanisms of the improved efficacy of this combined therapy.

METHODS

Mass spectrometry was performed to quantitatively detect drugs in haematoma fluids and serum samples from CSDH patients and also in cultured macrophages after treatment with either ATO alone or in combination with DEX. The differentiation and apoptosis of macrophages were evaluated using flow cytometry. The expression of cytokines, chemokines and angiogenesis-related proteins was evaluated using proteome profile arrays, immunoblots and ELISA, respectively.

RESULTS

ATO was detected in haematoma fluids and serum samples, whose levels were increased significantly in samples collected from patients treated with both ATO and DEX. ATO was also increased in cultured macrophages treated with ATO and DEX. The numbers of M1-polarized macrophages were higher than the M2 phenotype in the haematoma fluids of patients. Cultured macrophages treated with ATO and DEX had reduced numbers of M1-polarized macrophages, increased numbers of M2-polarized macrophages as compared to monotherapies, and decreased rate of apoptosis induced by high-dose DEX. DEX enhanced the anti-inflammatory and anti-angiogenic activity of ATO by suppressing VEGFA and other inflammatory angiogenic factors. Consistent with the finding, patients responded well to the drug treatments had lower serum levels of VEGFA.

CONCLUSIONS

We have shown for the first time that ATO given orally was detected in CSDH haematoma fluids. DEX enhances the anti-inflammatory and anti-angiogenic effects of ATO, primarily by increasing the presence of ATO in haematoma and macrophages and by regulating the functions of macrophages.

Preoperative MRI characteristics predict chronic subdural haematoma postoperative recurrence: a meta-analysis

PURPOSE

Prior studies have reported that preoperative T1 magnetic resonance imaging (MRI) signal iso- or hypointensity may indicate higher risk of postoperative chronic subdural haematoma recurrence (cSDH). The authors undertook a meta-analysis to determine whether preoperative MRI characteristics may predict recurrence and/or reoperation after initial surgical evacuation of cSDH.

MATERIALS AND METHODS

Embase, PubMed and Cochrane Library were queried to find articles published after 1990 that included data on preoperative brain MRIs obtained prior to burr hole or craniotomy haematoma evacuation of unilateral or bilateral cSDH and data on postoperative recurrence and/or repeat evacuation. The authors specifically investigated the T1 signal characteristics of the haematoma as they related to postoperative recurrence.

RESULTS

Five articles were identified that included preoperative MRI T1 signal characteristics and postoperative recurrence data. One study reported cSDH recurrence requiring reoperation as the primary outcome, whereas four studies reported SDH recurrence alone as the primary outcome. A total of 1081 patients with a total of 1290 cSDHs underwent surgical evacuation. In the combined analysis, there were 62 recurrences in 300 cases (20.7%) in the MRI T1 hypo- and/or iso-intensity groups and 59 recurrences in 885 cases (6.7%) in the MRI T1 other groups (combined odds ratio = 4.385 (95% CI 2.93-6.57)). There was low heterogeneity among studies (i² = 0%).

CONCLUSION

This meta-analysis suggests that preoperative MRI T1 hypo- or isointensity cSDH signal may predict increased postoperative SDH recurrence risk.

A Rare Case of Chronic Subdural Hematoma Coexisting With Metastatic Tumor

BACKGROUND

Incidence of chronic subdural hematoma (CSH) associated with metastases of extraneural malignancies is rare. We report a rare case of CSH wherein most of the CSH cavity was occupied with metastatic cancer cells; in addition, we review the literature.

CASE DESCRIPTION

A 68-year-old man with a history of gastric cancer presented to our hospital with dysarthria and shoulder paralysis; CSH was diagnosed from preoperative imaging findings. When the hematoma was removed via a small craniotomy, besides the hematoma, we observed an abnormal mass of tissue in the capsule. Pathologically, the mass was consistent with the findings of metastatic gastric cancer. Although the symptoms immediately disappeared postoperatively, a symptomatic acute subdural hematoma with midline shift was observed on postoperative day 27. Emergency craniotomy and hematoma and tumor removal were performed. Pathologic examination showed hemorrhagic necrosis in the tumor, which had not been initially observed. The postoperative course progressed without hematoma recurrence.

CONCLUSIONS

To the best of our knowledge, this is the first report of a CSH accompanied by tumor metastasis in most of the CSH cavity. Although rare, if a patient with cancer has CSH, the CSH should be treated considering the possibility of metastasis.

Skull angiosarcoma associated with a calcified chronic subdural hematoma

Angiosarcoma is an uncommon, aggressive endothelial-cell tumor that usually affects the skin, and involvement of the skull is rare. Here, we describe a case of skull angiosarcoma associated with a calcified chronic subdural hematoma (CSDH). HIGHLIGHTS A very rare case of skull angiosarcoma associated with a calcified chronic subdural hematoma is presented. An asymptomatic subdural hematoma with an atypical history and radiological features should prompt further investigation. Contrast MRI images should to be obtained early to differentiate a subdural hematoma from other pathologies.

Pathophysiology and Nonsurgical Treatment of Chronic Subdural Hematoma: From Past to Present to Future

BACKGROUND

Chronic subdural hematoma (CSDH) is one of the more frequent pathologic entities in daily neurosurgical practice. Historically, CSDH was considered progressive recurrent bleeding with a traumatic cause. However, recent evidence has suggested a complex intertwined pathway of inflammation, angiogenesis, local coagulopathy, recurrent microbleeds, and exudates. The aim of the present review is to collect existing data on pathophysiology of CSDH to direct further research questions aiming to optimize treatment for the individual patient.

METHODS

We performed a thorough literature search in PubMed, Ovid, EMBASE, CINAHL, and Google scholar, focusing on any aspect of the pathophysiology and nonsurgical treatment of CSDH.

RESULTS

After a (minor) traumatic event, the dural border cell layer tears, which leads to the extravasation of cerebrospinal fluid and blood in the subdural space. A cascade of inflammation, impaired coagulation, fibrinolysis, and angiogenesis is set in motion. The most commonly used treatment is surgical drainage. However, because of the pathophysiologic mechanisms, the mortality and high morbidity associated with surgical drainage, drug therapy (dexamethasone, atorvastatin, tranexamic acid, or angiotensin-converting enzyme inhibitors) might be a beneficial alternative in many patients with CSDH.

CONCLUSIONS

Based on pathophysiologic mechanisms, animal experiments, and small patient studies, medical treatment may play a role in the treatment of CSDH. There is a lack of level I evidence in the nonsurgical treatment of CSDH. Therefore, randomized controlled trials, currently lacking, are needed to assess which treatment is most effective in each individual patient.