Chronic subdural hematoma: a systematic review and meta-analysis of surgical procedures

Active Versus Passive Drainage Systems for Subdural Hematomas: A Systematic Review and Meta-Analysis

BACKGROUND AND OBJECTIVES

Chronic subdural hematoma (CSDH) management involves various surgical techniques, with drainage systems playing a pivotal role. While passive drainage (PD) and active drainage (AD) are both used, their efficacy remains contentious. Some studies favor PD for lower recurrence rates, while others suggest AD superiority. A systematic review and meta-analysis were conducted to address this controversy, aiming to provide clarity on optimal drainage modalities post-CSDH evacuation.

METHODS

This systematic review and meta-analysis followed preferred reporting items for systematic reviews guidelines, searching PubMed, Embase, and Web of Science until February 2024. Inclusion criteria focused on studies comparing active vs PD for subdural hematomas. Data extraction involved independent researchers, and statistical analysis was conducted using R software. The assessment of risk of bias was performed using the Risk of Bias in Non-Randomized Studies of Interventions framework and the Risk Of Bias 2 tool.

RESULTS

In this meta-analysis, involving 1949 patients with AD and 1346 with PD, no significant differences were observed in recurrence rates between the active (13.6%) and passive (16.4%) drainage groups (risk ratio [RR] = 0.87; 95% CI: 0.58-1.31). Similarly, for complications, infection, hemorrhage, and mortality, no significant disparities were found between the 2 drainage modalities. Complication rates were 7.5% for active and 12.6% for PD (RR = 0.74; 95% CI: 0.36-1.52). Infection rates were available for 635 patients of the active group, counting for 2% and 2.6%, respectively (RR = 0.98; 95% CI: 0.24-4.01). Hemorrhage rates were also available for 635 patients of the active group, counting for 1.1% and 2.2%, respectively (RR = 0.44; 95% CI: 0.11-1.81). Mortality rates were 2.7% and 2.5%, respectively (RR = 0.94; 95% CI: 0.61-1.46).

CONCLUSION

Our study found no significant difference between passive and AD for managing complications, recurrence, infection, hemorrhage, or mortality in CSDH cases. Further large-scale randomized trials are needed for clarity.

Establishment and validation of a CT-based prediction model for the good dissolution of mild chronic subdural hematoma with atorvastatin treatment

PURPOSE

To develop and validate a prediction model based on imaging data for the prognosis of mild chronic subdural hematoma undergoing atorvastatin treatment.

METHODS

We developed the prediction model utilizing data from patients diagnosed with CSDH between February 2019 and November 2021. Demographic characteristics, medical history, and hematoma characteristics in non-contrast computed tomography (NCCT) were extracted upon admission to the hospital. To reduce data dimensionality, a backward stepwise regression model was implemented to build a prognostic prediction model. We calculated the area under the receiver operating characteristic curve (AUC) of the prognostic prediction model by a tenfold cross-validation procedure.

RESULTS

Maximum thickness, volume, mean density, morphology, and kurtosis of the hematoma were identified as the most significant predictors of good hematoma dissolution in mild CSDH patients undergoing atorvastatin treatment. The prediction model exhibited good discrimination, with an area under the curve (AUC) of 0.82 (95% confidence interval [CI], 0.74-0.90) and good calibration (p = 0.613). The validation analysis showed the AUC of the final prognostic prediction model is 0.80 (95% CI 0.71-0.86) and it has good prediction performance.

CONCLUSION

The imaging data-based prediction model has demonstrated great prediction accuracy for good hematoma dissolution in mild CSDH patients undergoing atorvastatin treatment. The study results emphasize the importance of imaging data evaluation in the management of CSDH patients.

Advances in pathogenic mechanisms, diagnostic methods, surgical and non-surgical treatment, and potential recurrence factors of Chronic Subdural Hematoma: A review

Chronic Subdural Hematoma (CSDH) is a common hemorrhagic disease in neurosurgery, and with the intensification of global aging, its incidence is gradually increasing. With the advancement of scientific technology, the etiological concepts and surgical treatments for CSDH have continually evolved over time. Currently, neuroscientists' understanding of CSDH is no longer confined to bridging vein rupture; exploration of various mechanisms such as angiogenesis, maturation of blood vessels, and inflammation is also underway. In-depth exploration and discovery of pathogenic mechanisms guide the updating of clinical treatment strategies and methods. For different types of CSDH, there is now a clear guidance for the targeted selection of treatment methods. However, the current treatment of CSDH cannot completely solve all problems, and the updating of treatment methods as well as the development and validation of new effective drugs remain challenges for the future. In addition, the recurrence of CSDH is a significant issue that needs to be addressed. Although we have reviewed potential recurrent factors that may be associated, the strength of this evidence is insufficient. Future research should gradually focus on validating these recurrent factors and exploring new ones, in order to optimize the existing understanding and treatment of CSDH.

Comparative clinical outcomes of irrigation techniques in burr-hole craniostomy for chronic subdural hemorrhage: a multicenter cohort study

BACKGROUND

Chronic Subdural Hemorrhage(cSDH) is often treated with surgical blood drainage, but concerns about recurrence and outcomes persist. Surgical techniques, including irrigation, vary. This study compares the outcomes of irrigation in cSDH surgery.

MATERIALS AND METHODS

From September 2020 to September 2022, 92 cSDH patients underwent surgery. Two different irrigation methods were used: extensive irrigation (IG) and non-irrigation (NIG). Method of irrigation was selected by each surgeon's preference. Parameters measured included volume of hematoma changes, midline shifting, complications, and basic demographics. Recurrence was defined as symptomatic or hematoma expansion more than double the volume before surgery. Factors predicting recurrence and irrigation method impact were analyzed.

RESULTS

Eleven patients were excluded because of bilateral or related to other disease. We analyzed 81 patients (44 NIG, 37 IG). Recurrence occurred in 6 IG cases (16.2%) and 1 NIG case (2.3%). Irrigation method significantly affected recurrence (P = 0.043). Age, gender, medication, medical history, and preoperative measurements had no major impact on recurrence. NIG had unexpected cases of intracerebral hemorrhage.

CONCLUSION

Extensive irrigation may increase recurrence in cSDH drainage. Non-irrigation drainage had fewer recurrences, but unexpected complications arose. Careful drainage in non-irrigated cases is crucial.

Comparative analysis of surgical techniques in the management of chronic subdural hematomas and risk factors for poor outcomes

Chronic subdural hematomas (CSDH) are increasingly prevalent, especially among the elderly. Surgical intervention is essential in most cases. However, the choice of surgical technique, either craniotomy or burr-hole opening, remains a subject of debate. Additionally, the risk factors for poor long-term outcomes following surgical treatment remain poorly described. This article presents a 10-year retrospective cohort study conducted at a single center that aimed to compare the outcomes of two common surgical techniques for CSDH evacuation: burr hole opening and minicraniotomy. The study also identified risk factors associated with poor long-term outcome, which was defined as an mRS score ≥ 3 at 6 months. This study included 582 adult patients who were surgically treated for unilateral CSDH. Burr-hole opening was performed in 43% of the patients, while minicraniotomy was performed in 57%. Recurrence was observed in 10% of the cases and postoperative complications in 13%. The rates of recurrence, postoperative complications, death and poor long-term outcome did not differ significantly between the two surgical approaches. Multivariate analysis identified postoperative general complications, recurrence, and preoperative mRS score ≥ 3 as independent risk factors for poor outcomes at 6 months. Recurrence contribute to a poorer prognosis in CSDH. Nevertheless, use burr hole or minicraniotomy for the management of CSDH showed a similar recurrence rate and no significant differences in post-operative outcomes. This underlines the need for a thorough assessment of patients with CSHD and the importance of avoiding their occurrence, by promoting early mobilization of patients. Future research is necessary to mitigate the risk of recurrence, regardless of the surgical technique employed.

Technical report: clinical feasibility of augmented reality-navigated chronic subdural hematoma evacuation

Management of chronic subdural hematoma (cSDH) poses unique challenges and can be fraught with complications. Understanding the spatial relationships of cSDH to adjacent brain tissue and skull topography is critical for successful surgical treatment. The aim of this report is to highlight the feasibility and efficacy of a novel augmented reality (AR) overlay tool for surgical planning with technical description of two surgical cases using AR for surgical management of cSDH. This report describes a fiducial-less AR system for surgical planning of surgical evacuation of cSDH. The AR system was used to superimpose 3D anatomy onto the patients head to provide image guidance during two cases of evacuation. Imaging demonstrated convexity cSDH. A 3D model of the patient's anatomy was created and registered onto the patients' heads using a novel AR system. Surgical evacuation of the cSDH was completed in each case with surgical planning assisted by AR overlay.

Middle meningeal artery patency after surgical evacuation for chronic subdural hematoma

BACKGROUND

Chronic subdural hematoma (CSDH) often requires surgical evacuation, but recurrence rates remain high. Middle meningeal artery (MMA) embolization (MMAE) has been proposed as an alternative or adjunct treatment. There is concern that prior surgery might limit patency, access, penetration, and efficacy of MMAE, such that some recent trials excluded patients with prior craniotomy. However, the impact of prior open surgery on MMA patency has not been studied.

METHODS

A retrospective analysis was conducted on patients who underwent MMAE for cSDH (2019-2022), after prior surgical evacuation or not. MMA patency was assessed using a six-point grading scale.

RESULTS

Of the 109 MMAEs (84 patients, median age 72 years, 20.2% females), 58.7% were upfront MMAEs, while 41.3% were after prior surgery (20 craniotomies, 25 burr holes). Median hematoma thickness was 14 mm and midline shift 3 mm. Hematoma thickness reduction, surgical rescue, and functional outcome did not differ between MMAE subgroups and were not affected by MMA patency or total area of craniotomy or burr-holes. MMA patency was reduced in the craniotomy group only, specifically in the distal portion of the anterior division (p = 0.005), and correlated with craniotomy area (p < 0.001).

CONCLUSION

MMA remains relatively patent after burr-hole evacuation of cSDH, while craniotomy typically only affects the frontal-distal division. However, MMA patency, evacuation method, and total area do not affect outcomes. These findings support the use of MMAE regardless of prior surgery and may influence future trial inclusion/exclusion criteria. Further studies are needed to optimize the timing and techniques for MMAE in cSDH management.

Middle meningeal artery embolization for chronic subdural hematoma: A single-center experience and predictive modeling of outcomes

BACKGROUND

Remarkable interest is rising around middle meningeal artery embolization (MMAE) as an emerging alternative therapy for chronic subdural hematoma (cSDH). The study aims to highlight a large center experience and the variables associated with treatment failure and build experimental machine learning (ML) models for outcome prediction.

MATERIAL AND METHODS

A 2-year experience in MMAE for managing patients with chronic subdural hematoma was analyzed. Descriptive statistical analysis was conducted using imaging and clinical features of the patients and cSDH, which were subsequently used to build predictive models for the procedure outcome. The modeling evaluation metrics were the area under the ROC curve and F1-score.

RESULTS

A total of 100 cSDH of 76 patients who underwent MMAE were included with an average follow-up of 6 months. The intervention had a per procedure success rate of 92%. Thrombocytopenia had a highly significant association with treatment failure. Two patients suffered a complication related to the procedure. The best performing machine learning models in predicting MMAE failure achieved an ROC-AUC of 70%, and an F1-score of 67%, including all patients with or without surgical intervention prior to embolization, and an ROC-AUC of 82% and an F1-score of 69% when only patients who underwent upfront MMAE were included.

CONCLUSION

MMAE is a safe and minimally invasive procedure with great potential in transforming the management of cSDH and reducing the risk of surgical complications in selected patients. An ML approach with larger sample size might help better predict outcomes and highlight important predictors following MMAE in patients with cSDH.

Delayed Manifestation of Massive Bilateral Sub-acute Subdural Hemorrhage

Sub-acute subdural hematoma (SASDH) in the elderly is a challenging diagnosis given its insidious onset and nonspecific presentation, particularly following minor head trauma. This case report highlights the clinical features, diagnostic challenges, and management of SASDH in an elderly patient. A 72-year-old male presented with a five-day history of giddiness, headache, and balance issues, which began suddenly without a significant triggering event. His medical history was notable only for a minor fall approximately one month before presentation, after which he experienced no immediate or significant symptoms. An MRI at an outside hospital revealed bilateral frontoparietotemporal SASDHs with diffuse cerebral edema. The patient underwent a bilateral mini craniotomy for hematoma evacuation and was managed postoperatively with anti-seizure medications and supportive care, resulting in a satisfactory outcome. The diagnosis of SASDH requires a high index of suspicion, especially in the elderly, who may present with vague and progressive symptoms following minor head trauma. Early and accurate diagnosis via imaging, particularly MRI, is crucial for effective management. Surgical intervention, typically involving hematoma evacuation, significantly improves outcomes in patients with SASDH, underscoring the importance of timely surgical referral and treatment. Elderly patients presenting with unexplained neurological symptoms following even minor trauma should be evaluated for SASDH. Early recognition and intervention are crucial to prevent long-term morbidity and mortality in this vulnerable population.

Embolization of the middle meningeal artery for the prevention of chronic subdural hematoma recurrence in high-risk patients: a randomized controlled trial-the EMPROTECT study protocol

BACKGROUND

Middle meningeal artery (MMA) embolization has been proposed as a treatment of chronic subdural hematoma (CSDH). The benefit of the procedure has yet to be demonstrated in a randomized controlled trial. We aim to assess the efficacy of MMA embolization in reducing the risk of CSDH recurrence 6 months after burr-hole surgery compared with standard medical treatment in patients at high risk of postoperative recurrence.

METHODS

The EMPROTECT trial is a multicenter open label randomized controlled trial (RCT) involving 12 French centers. Adult patients (≥18 years) operated for CSDH recurrence or for a first episode with a predefined recurrence risk factor are randomized 1:1 to receive either MMA embolization within 7 days of the burr-hole surgery (experimental group) or standard medical care (control group). The number of patients to be included is 342.

RESULTS

The primary outcome is the rate of CSDH recurrence at 6 months. Secondary outcomes include the rate of repeated surgery for a homolateral CSDH recurrence during the 6-month follow-up period, the rate of disability and dependency at 1 and 6 months, defined by a modified Rankin Scale (mRS) score ≥4, mortality at 1 and 6 months, total cumulative duration of hospital stay during the 6-month follow-up period, directly or indirectly related to the CSDH and embolization procedure-related complication rates.

CONCLUSIONS

The EMPROTECT trial is the first RCT evaluating the benefit of MMA embolization as a surgical adjunct for the prevention of CSDH recurrence. If positive, this trial will have a significant impact on patient care.

TRIAL REGISTRATION NUMBER

NCT04372147.

Retrospective Analysis of Risk Factors for Recurrence of Chronic Subdural Haematoma after Surgery

(1) Background: In this study, epidemiological, clinical, therapeutical, and haemostaseological variables were investigated regarding their correlation with the recurrence of chronic subdural haematomas to assess the risk of recurrence more reliably in everyday clinical practice. (2) Methods: In our retrospective study, the electronic records of 90 patients who underwent surgery for a chronic subdural haematoma at our institute between 1 January 2017 and 31 May 2021 were analysed regarding previously defined variables. (3) Results: In the patient collective, 33.33% of the 90 patients experienced a recurrence requiring treatment. The occurrence of a recurrence was not statistically significantly related to age, gender, known alcohol abuse, a specific location, extension over one or both hemispheres, the surgical method, or anticoagulant medication. However, the recurrence was statistically significantly related to haematoma width (p = 0.000007), septation (p = 0.005), and the existence of a coagulation disorder not treated with medication (p = 0.04). (4) Conclusions: In our study, the width of the haematoma, septation, and coagulation disorders not treated with medication were documented as risk factors for the occurrence of a chronic subdural haematoma. Identifying of these risk factors could help in adapting individual therapeutic concepts for chronic subdural haematomas.

Evaluation of Effectiveness of Atorvastatin in Treating Chronic Subdural Hematoma not Requiring Surgery: A Meta-Analysis of Randomized Controlled Trials

Chronic subdural hematoma (CSDH) is a chronic space-occupying lesion formed by blood accumulation between the arachnoid membrane and the dura mater. Atorvastatin is of increasing clinical interest for CSDH. We performed a meta-analysis of published randomized controlled trials (RCTs) and used objective data as the primary outcomes to provide an evidence-based analysis of the efficacy of atorvastatin for CSDH treatment. Databases of MEDLINE (via PubMed), EMBASE, the Cochrane Library, Scopus, Web of Science, ScienceDirect, Chinese National Knowledge Infrastructure (CNKI), Cqvip database (CQVIP), and Wanfang database were systematically searched for RCTs reporting the use of atorvastatin for CSDH treatment. Odds ratio (OR), standard mean difference (SMD), and 95% confidence intervals (CIs) were used as summary statistics. I-square (I2) test was performed to assess the impact of study heterogeneity on the results of the meta-analysis. Nine relevant RCTs with 611 patients were identified for inclusion in this meta-analysis. Compared to controls, atorvastatin treatment had a significantly higher effectiveness (OR: 7.41, 95% CI: 3.32-16.52, P < 0.00001, I2 = 0%), lower hematoma volume (SMD: -0.46. 95% CI: -0.71 to -0.20, P = 0.0005, I2 = 0%), higher activities of daily living-Barthel Index (ADL-BI) (SMD: 2.07, 95% CI: 1.06-3.09, P < 0.0001, I2 = 92%), and smaller Chinese stroke scale (CSS) (SMD: -1.10, 95% CI: -1.72 to -0.48, P = 0.0005, I2 = 57%). In view of these findings, we conclude that the outcomes of experimental group are superior to the control group with respect to effectiveness, hematoma volume, ADL-BI, and CSS based on nine RCTs with 611 patients. Atorvastatin is beneficial to CSDH patients without surgery.

Patient perception and satisfaction in awake burr hole trepanation under local anesthesia for evacuation of chronic subdural hematoma

Evacuation of chronic subdural hematoma (CSDH) will be one of the most common neurosurgical procedures in the future in the increasingly aging societies. Performing cranial surgery on awake patients may place a psychological burden on them. Aim of this study was to evaluate the psychological distress of patients during awake CSDH relief. Patients with awake evacuation of CSDH via burr hole trepanation were included in our monocentric prospective study. Patient perception and satisfaction were measured using standardized surveys 3-5 days and 6 months after surgery. Among other questionnaires, the Hospital Anxiety and Depression and the Impact of Event Scale, were used to quantify patients' stress. A total of 50 patients (mean age 72.9 years (range 51 - 92)) were included. During surgery, 28 patients reported pain (mean 4.1 (SD 3.3)). Postoperatively, 26 patients experienced pain (mean 2.7 (SD 2.6)). Patients' satisfaction with intraoperative communication was reported with a mean of 8.3 (SD 2.1). There was a significant negative correlation between intraoperatively perceived pain and satisfaction with intraoperative communication (p = 0.023). Good intraoperative communication during evacuation of CSDH in awake patients is associated with positive patient perception and correlates with pain reduction.

Efficacy and safety of steroids for chronic subdural hematoma: A systematic review and meta-analysis

Background

Chronic subdural hematoma (CSDH) is a condition characterized by the accumulation of fluid, blood, and blood breakdown products between the brain's arachnoid and dura mater coverings. While steroids have been explored as a potential treatment option, their efficacy and safety remain uncertain. This meta-analysis and systematic review aimed to assess the impact of steroids on CSDH management, including mortality, recurrence, complications, and functional outcomes.

Methods

We conducted a comprehensive literature search in major electronic databases up to June 2023, following Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and Cochrane Handbook for Systematic Reviews and Interventions. Inclusion criteria encompassed adult patients with CSDH, the use of steroids as monotherapy or adjuvant therapy, and clearly defined outcomes. Randomized controlled trials and cohort studies meeting these criteria were included in the study.

Results

The initial search yielded 4315 articles, with 12 studies meeting the inclusion criteria. Our findings indicate a non-significant trend toward reduced mortality with steroids in combination with standard care (Odds ratios [OR] = 0.66, 95% confidence interval [CI] 0.20-2.18). However, substantial heterogeneity was observed (I2 = 70%). Sensitivity analysis, excluding influential studies, suggested a potential increased mortality risk associated with steroids (OR = 1.47, 95% CI 0.87-2.48). Steroids showed a possible benefit in reducing the recurrence of CSDH (OR = 0.58, 95% CI 0.20-1.67), but with significant heterogeneity (I2 = 89%). No clear advantage of steroids was observed in terms of functional outcomes at three months (modified Rankin scale scores). Furthermore, steroids were associated with a significantly higher incidence of adverse effects and complications (OR = 2.17, 95% CI 1.48-3.17).

Conclusion

Steroids may have a potential role in reducing CSDH recurrence but do not appear to confer significant advantages in terms of mortality or functional outcomes. However, their use is associated with a higher risk of adverse effects and complications. Given the limitations of existing studies, further research is needed to refine the role of steroids in CSDH management, considering patient-specific factors and treatment protocols.

Time-of-flight magnetic resonance angiography for detection of postoperative recurrence in patients with chronic subdural hematoma

PURPOSE

Chronic subdural hematoma (CSDH) is associated with postoperative recurrence. Although various factors are involved in postoperative recurrence of CSDH, blood flow, especially in the middle meningeal artery (MMA), is considered to play an important role. We investigated whether the degree of signal intensity (SI) of the MMA on time-of-flight magnetic resonance angiography (TOF MRA) and various clinical factors are involved in recurrence of CSDH.

METHODS

The maximum SI of both MMAs was measured on TOF MRA images within 1 month before or after the initial surgery.

RESULTS

In total, 185 patients (20 with and 165 without recurrence of CSDH) were included in the analysis. The SI ratio and dementia were significant predictors of recurrence of CSDH (SI ratio: odds ratio [95% confidence interval (CI)] = 1.71 [1.32, 2.22], p < 0.0001; dementia: odds ratio [95% CI] = 7.41 [1.83, 30.1], p = 0.005). The estimated regression coefficients in the final model were 6.14 for the SI ratio and 1.28 for dementia. The risk score was derived according to these regression coefficients as follows: score = 5 × SI ratio + 1 (dementia: yes). With a score of 5, the predicted probability of recurrence was 2% [95% CI 0.7, 5.7], whereas with scores of 8 and 10, the probability was 43.3% [27.0, 61.1] and 89.5% [65.7, 97.5], respectively, which increased the risk of recurrence.

CONCLUSION

Patients with an increased SI ratio of the affected MMA on TOF MRA who underwent surgery for CSDH were significantly more likely to experience recurrence.

Non-surgical management of chronic subdural hematoma: insights and future perspectives from an international survey including neurosurgeons from 90 countries worldwide

BACKGROUND

Chronic subdural hematoma (cSDH) is one of the most common neurosurgical conditions. Although surgical evacuation is still the gold standard for treatment, recent advances have led to the development of other management strategies, such as medical therapies and endovascular middle meningeal artery (MMA) embolization. Through this international survey, we investigated the global trends in cSDH management, focusing on medical and endovascular treatments.

DESIGN AND PARTICIPANTS

A 14-question, web-based, anonymous survey was distributed to neurosurgeons worldwide.

RESULTS

Most responders do not perform MMA embolization (69.5%) unless for specific indications (29.6%). These indications include residual cSDH after surgical evacuation (58.9%) or cSDH in patients on antiplatelet medications to avoid surgical evacuation (44.8%). Survey participants from teaching versus non-teaching hospitals (p = 0.002), public versus private hospitals (p = 0.022), and Europe versus other continents (p < 0.001) are the most users of MMA embolization. A large number of participants (51%) declare they use a conservative/medical approach, mainly to avoid surgery in patients with small cSDH (74.8%).

CONCLUSIONS

This survey highlights the current trends of cSDH management, focusing on conservative and MMA embolization treatment strategies. Most responders prefer a conservative approach for patients with small cSDHs not requiring surgical evacuation. However, in higher-risk scenarios such as residual hematomas after surgery or patients on antiplatelet medications, MMA embolization is regarded as a reasonable option by participants. Future studies should clarify the indications of MMA embolization, including appropriate patient selection and efficacy as a stand-alone procedure.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: An Analysis of 35 Consecutive Patients

INTRODUCTION

There is sufficient scientific literature that demonstrates favorable outcomes using the minimally invasive technique of middle meningeal artery embolization (MMAE) for the treatment of chronic subdural hematomas (cSDH). The authors evaluate the outcomes of 35 consecutive patients treated with MMAE, both with and without adjuvant surgical drainage (ASD), in an attempt to identify variables that may affect the outcome of patients treated with MMAE for cSDH.

METHODS

A multivariate retrospective analysis was performed on patients who received MMAE for cSDH, including age, size of cSDH, ASD, presence of unilateral or bilateral collections, and use of anticoagulants.

RESULTS

Twenty patients underwent MMAE with planned ASD, while 15 patients had MMAE only; these groups had an average cSDH size reduction (measured at its greatest width) of 74% and 69% of cSDH, respectively. Of the 15 patients who were initially treated only with MMAE, three (20%) required a rescue craniotomy. Twenty patients (57%) who had initially presented while receiving oral anticoagulants had an average of 71% size reduction with ASD compared to 74% reduction in those without ASD. Patients not using anticoagulants had an 84% and 78% average reduction in size, respectively. Twelve patients presented with bilateral cSDH; patients who received ASD had an average size reduction of 58%; those without ASD had 63%. Patients with unilateral cSDH had 85% and 83% reduction in size, respectively.

CONCLUSION

Middle meningeal artery embolization, with or without ASD, can be a useful alternative or adjunct to standard surgical treatment for cSDH. Our study found that only three of 35 patients (9%) treated with this method required any further surgical intervention. No patient who received ASD had a recurrence of their cSDH. Further investigation, including prospective randomized studies, would be useful to better identify which patients can benefit and variables that impact the outcome of patients undergoing MMAE.

Reducing morbidity associated with subdural drain placement after burr-hole drainage of unilateral chronic subdural hematomas: a retrospective series comparing conventional and modified Nelaton catheter techniques

PURPOSE

Placement of a subdural drain after burr-hole drainage of chronic subdural hematoma (cSDH) significantly reduces risk of its recurrence and lowers mortality at 6 months. Nonetheless, measures to reduce morbidity related to drain placement are rarely addressed in the literature. Toward reducing drain-related morbidity, we compare outcomes achieved by conventional insertion and our proposed modification.

METHODS

In this retrospective series from two institutions, 362 patients underwent burr-hole drainage of unilateral cSDH with subsequent subdural drain insertion by conventional technique or modified Nelaton catheter (NC) technique. Primary endpoints were iatrogenic brain contusion or new neurological deficit. Secondary endpoints were drain misplacement, indication for computed tomography (CT) scan, re-operation for hematoma recurrence, and favorable Glasgow Outcome Scale (GOS) score (≥ 4) at final follow-up.

RESULTS

The 362 patients (63.8% male) in our final analysis included drains inserted in 56 patients by NC and 306 patients by conventional technique. Brain contusions or new neurological deficits occurred significantly less often in the NC (1.8%) than conventional group (10.5%) (P = .041). Compared with the conventional group, the NC group had no drain misplacement (3.6% versus 0%; P = .23) and significantly fewer non-routine CT imaging related to symptoms (36.5% versus 5.4%; P < .001). Re-operation rates and favorable GOS scores were comparable between groups.

CONCLUSION

We propose the NC technique as an easy-to-use measure for accurate drain positioning within the subdural space that may yield meaningful benefits for patients undergoing treatment for cSDH and vulnerable to complication risks.

Risk factors for recurrence of chronic subdural hematoma after surgical evacuation: a systematic review and meta-analysis

Chronic subdural hematoma (CSDH) is a common neurosurgical condition. Surgical evacuation has remained the primary treatment despite many advancements in the endovascular field. Regardless, recurrence requiring reoperation is commonly observed during the postoperative follow-up. Herein, we aimed to investigate risk factors for recurrence after surgical evacuation. A review of MEDLINE, EMBASE, Web of Science, and Scopus was conducted using the designed search string. Studies were reviewed based on the predefined eligibility criteria. Data regarding sixty potential risk factors along with operational information were extracted for analysis. A meta-analysis using the random-effect model was conducted, and each risk factor affecting the postoperative recurrence of CSDH was then evaluated and graded. A total of 198 records met the eligibility criteria. A total number of 8523 patients with recurrent CSDH and 56,096 with non-recurrent CSDH were included in the study. The recurrence rate after surgical evacuation was 12%. Fifteen preoperative, nine radiologic, four hematoma-related, and three operative and postoperative factors were associated with recurrence. Risk factors associated with recurrence after surgical evacuation are important in neurosurgical decision-making and treatment planning. Found risk factors in this study may be used as the basis for pre-operative risk assessment to choose patients who would benefit the most from surgical evacuation.

Drainage versus no drainage after burr-hole evacuation of chronic subdural hematoma: a systematic review and meta-analysis of 1961 patients

Chronic subdural hematoma (cSDH) is a common neurosurgical condition that can cause severe morbidity and mortality. cSDH recurs after surgical evacuation in 5-30% of patients, but drains may help reduce this risk. We aimed to investigate the effect of drainage versus no drainage on the rates of recurrence and mortality, as well as the clinical outcomes of cSDH. Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines, we searched four electronic databases (PubMed, Cochrane Library, Scopus, and Web of Science) to identify eligible studies reported up to June 2022. Using Review Manager software, we reported four primary outcomes as odds ratios (ORs) and confidence intervals (CIs). The meta-analysis included a total of 10 studies with 1961 patients. The use of drainage was found to be significantly more effective than non-drainage in reducing the "mortality rate" (OR = 0.65, 95% CI 0.43 to 0.97; P = 0.04), the "recurrence rate" (OR = 0.39, 95% CI 0.28 to 0.55; P < 0.00001), and occurrence of "gross focal neurological deficit" (OR = 0.58, 95% CI 0.37 to 0.89; P = 0.01). No significant difference was found in the occurrence of a Glasgow Coma Scale score of 15 (OR = 1.21, 95% CI 0.84 to 1.76; P = 0.30). The use of drains after burr-hole irrigation reduces the recurrence, mortality, and gross focal neurological deficit rates of chronic subdural hematomas.

Middle meningeal artery embolization and pediatric chronic subdural hematoma: a systematic review of the literature

Chronic subdural hematoma (CSDH) is a disease commonly found in the elderly and not a typical finding in pediatric population. History of shunt surgery, child abuse, and blood disorder are some of the common causes of pediatric CSDH (pCSDH). There is growing evidence about the role of middle meningeal artery embolization (MMAE) to manage CSDH in the elderly population with a high risk of rebleeding. However, the evidence in the pediatric population is still sparse. A systematic literature search was conducted on PubMed, Scopus, and Web of Science database from January, 2023, to March, 2023. Search strings were generated based on the combination of modified search terms, such as CSDH, MMA embolization, and child. Risk of bias was assessed using the Cochrane Risk of Bias in Nonrandomized Study for Intervention. Nine articles were included in this review. The success rate of MMA embolization in pediatric CSDH was 88.8%. Histories of ventriculoperitoneal shunt, blood coagulation disorder, and trauma were the causes of CSDH. Time to achieve success was varied from 2 to 9 months. No study with low risk of bias was found. This systematic review found no high-quality evidence regarding the role of MMA embolization in the management of pCSDH. However, due to its high success rate, MMAE could be a promising approach to treat pCSDH.

Factors Associated With Short-Term Outcomes of Burr-Hole Craniostomy Associated With Brain Re-Expansion and Subdural Hematoma Shrinkage for Chronic Subdural Hematoma

Objective

Chronic subdural hematoma (CSDH) is a commonly encountered neurosurgical pathology that frequently requires surgical intervention. With an increasingly aging demographic, more older people and patients with comorbidities will present with symptomatic CSDH. This study evaluated clinical and laboratory factors affecting the short-term outcomes of CSDH after surgical intervention.

Methods

We retrospectively analyzed 170 patients who underwent burr-hole trephination for CSDH in a single institution from January 2019 to December 2021. All patients were examined for risk factors and evaluated for hematoma thickness change and midline shifting on brain computed tomography (CT) scans at 3 days after burr-hole trephination.

Results

This consecutive series of patients included 114 males (67.1%) and 56 females (32.9%); mean age 72.4±12.5 years. Renal disease (p=0.044) and prior intracranial hemorrhage (p=0.004) were clinical factors associated with poorer prognosis. A statistically significant association was found between initial laboratory findings, including high creatine kinase (p=0.025) and low platelet (p=0.036) levels, and CT findings 3 days postoperatively. The 3-day mean arterial pressure and postoperative ambulation were not significantly associated with outcomes.

Conclusion

Burr-hole craniostomy is an effective surgical procedure for initial CSDH. However, patients with a history intracranial hemorrhage and abnormal laboratory findings, such as low platelet levels, who underwent burr-hole trephination had poor short-term outcomes. Therefore, these patients should be carefully monitored.

Intraoperative irrigation of artificial cerebrospinal fluid and temperature of irrigation fluid for chronic subdural hematoma: a systematic review and meta-analysis

Purpose

To systematically review the different types of irrigation fluid and the different temperatures of irrigation fluid on postoperative recurrence rates in the evacuation of chronic subdural hematoma (CSDH).

Methods

We conducted a comprehensive search of electronic databases, including PubMed, Embase, the Cochrane Library, the China National Knowledge Infrastructure (CNKI), WanFang, the Chinese VIP Information (VIP), and China Biology Medicine (CBM), and reference lists of relevant studies to identify all eligible studies. Two reviewers independently screened the titles and abstracts for inclusion, and the full-text articles were assessed for eligibility based on predetermined inclusion and exclusion criteria. Data were extracted using a standardized form, and the quality of the studies was assessed using a risk of bias tool. Meta-analyses were performed using a fixed-or random-effects model, and heterogeneity was assessed using the I2 statistic. The primary endpoint was the postoperative recurrence rate.

Results

After stringent screening, a total of 11 studies were identified, including six English publications, four Chinese publications, and one Japanese publication, involving a population of 29,846 patients. Our meta-analysis provides evidence that artificial cerebrospinal fluid (ACF) could decrease the post-operative recurrence rate by 47% after the evacuation of CSDH when compared to normal saline (NS) [(odds ratio) OR 0.53, 95% confidence intervals (CI): 0.31-0.90, p = 0.02, I² = 67%]. Besides, the irrigation fluid at body temperature could decrease the postoperative recurrence rate of CSDH by 64% when compared to room temperature (OR = 0.36, 95% CI = 0.22-0.59, p < 0.0001, I² = 0%).

Conclusion

Our analysis revealed significant difference in the choice of irrigation fluid for CSDH surgery. Notably, we found that irrigation with fluid at body temperature demonstrated superiority over irrigation with fluid at room temperature, resulting in fewer instances of recurrence. This straightforward technique is both safe and widely available, providing an opportunity to optimize outcomes for patients with CSDH. Our findings suggest that the use of body-temperature NS or ACF of room temperature during operation should be considered a standard of procedure in CSDH surgery. Nevertheless, whether the different temperature of ACF could be considered a standard of procedure in CSDH surgery still need high-quality RCTs to further identify.

Systematic review registration

https://www.crd.york.ac.uk/prospero/; Identifier CRD42023424344.

Burr hole locations are associated with recurrence in single burr hole drainage surgery for chronic subdural hematoma

Background

Various factors have been reported as risk factors for chronic subdural hematomas (CSDH) recurrence. However, few studies have quantitatively evaluated the impact of CSDH locations and burr hole positions on recurrence. This study aimed to reveal the relation between CSDH recurrence and the locations of CSDH and burr holes.

Methods

Initial single burr hole surgeries for CSDH with a drainage tube between April 2005 and October 2021 at Otemae Hospital were enrolled. Patients' medical records, CSDH volume, and CSDH computed tomography values (CTV) were evaluated. The locations of CSDH and burr holes were assessed using Montreal Neurological Institute coordinates.

Results

A total of 223 patients were enrolled, including 34 patients with bilateral CSDH, resulting in 257 surgeries investigated. The rate of CSDH recurrence requiring reoperation (RrR) was 13.5%. The RrR rate was significantly higher in patients aged ≥76 years, those with bilateral CSDH, and those with postoperative hemiplegia. In RrR, the preoperative CSDH volume was significantly larger, and CTV was significantly smaller. The locations of CSDH had no influence on recurrence. However, in RrR, the locations of burr holes were found to be more lateral and more ventral. Multivariate Cox proportional hazards regression analysis showed that bilateral CSDH, more ventral burr hole positions, and postoperative hemiplegia were risk factors for recurrence.

Conclusions

The locations of burr holes are associated with CSDH recurrence. In RrR, CSDH profiles tend to show a larger volume and reduced CTV. Hemiplegia after burr hole surgery serves as a warning sign for RrR.

Surgical techniques for evacuation of chronic subdural hematoma: a mini-review

Chronic subdural hematoma is one of the most common neurosurgical pathologies with over 160,000 cases in the United States and Europe each year. The current standard of care involves surgically evacuating the hematoma through a cranial opening, however, varied patient risk profiles, a significant recurrence rate, and increasing financial burden have sparked innovation in the field. This mini-review provides a brief overview of currently used evacuation techniques, including emerging adjuncts such as endoscopic assistance and middle meningeal artery embolization. This review synthesizes the body of available evidence on efficacy and risk profiles for each critical aspect of surgical technique in cSDH evacuation and provides insight into trends in the field and promising new technologies.

Short-term follow-up pilot study of sole middle meningeal artery embolization for chronic subdural hematoma: influence of internal architecture on the radiological outcomes

PURPOSE

To identify prognostic factors with emphasis on chronic subdural hematoma (CSDH) architecture that determines short-term outcome of middle meningeal artery embolization (MMAE).

METHODS

Consecutive CSDH patients treated by MMAE (November 2019 and March 2022) were retrospectively analyzed. Four architectures were analyzed: homogeneous, laminar, separated, and trabecular types. Predictor variables from baseline CT were correlated with radiological endpoint (≥ 50% of hematoma volume reduction), time to reach the endpoint, and rate of volume reduction.

RESULTS

Study included 50 patients with 56 CSDHs (median age [first quartile, Q1; third quartile, Q3] 70.5 [60, 78.3] years; 36 were men). Separated type reached the endpoint at a lower rate on both bivariate (p = 0.02) and multivariate Cox model (0.034). Kaplan-Meier curves demonstrated that the median [Q1, Q3] time for 50% of the hematomas to reach the endpoint was 5 [4, 8], 4 [3, 5], 15 [15, 15], and 11 [4, 19] weeks for homogeneous, laminar, separated, and trabecular types, respectively. Linear mixed-effect model demonstrated a significant variation in the slope of hematoma volume reduction that was - 4.16 (95% confidence interval [CI] - 5.4, - 2.9), - 6.7 (95% CI - 8.35, - 5.1), - 2.03 (95% CI - 4.14, 0.08), and - 5.06 (95% CI - 6.8, - 3.32) ml per week for homogeneous, laminar, separated, and trabecular subtypes, respectively.

CONCLUSION

Separated CSDH is a poor prognostic type in achieving radiological endpoint and a slower rate of volume reduction. While, homogeneous and laminar types reached the endpoint faster than separated and trabecular types on short-term follow-up.

Middle Meningeal Artery Embolization for Chronic Subdural Hematoma: Predictors of Clinical and Radiographic Failure from 636 Embolizations

Background Knowledge regarding predictors of clinical and radiographic failures of middle meningeal artery (MMA) embolization (MMAE) treatment for chronic subdural hematoma (CSDH) is limited. Purpose To identify predictors of MMAE treatment failure for CSDH. Materials and Methods In this retrospective study, consecutive patients who underwent MMAE for CSDH from February 2018 to April 2022 at 13 U.S. centers were included. Clinical failure was defined as hematoma reaccumulation and/or neurologic deterioration requiring rescue surgery. Radiographic failure was defined as a maximal hematoma thickness reduction less than 50% at last imaging (minimum 2 weeks of head CT follow-up). Multivariable logistic regression models were constructed to identify independent failure predictors, controlling for age, sex, concurrent surgical evacuation, midline shift, hematoma thickness, and pretreatment baseline antiplatelet and anticoagulation therapy. Results Overall, 530 patients (mean age, 71.9 years ± 12.8 [SD]; 386 men; 106 with bilateral lesions) underwent 636 MMAE procedures. At presentation, the median CSDH thickness was 15 mm and 31.3% (166 of 530) and 21.7% (115 of 530) of patients were receiving antiplatelet and anticoagulation medications, respectively. Clinical failure occurred in 36 of 530 patients (6.8%, over a median follow-up of 4.1 months) and radiographic failure occurred in 26.3% (137 of 522) of procedures. At multivariable analysis, independent predictors of clinical failure were pretreatment anticoagulation therapy (odds ratio [OR], 3.23; P = .007) and an MMA diameter less than 1.5 mm (OR, 2.52; P = .027), while liquid embolic agents were associated with nonfailure (OR, 0.32; P = .011). For radiographic failure, female sex (OR, 0.36; P = .001), concurrent surgical evacuation (OR, 0.43; P = .009), and a longer imaging follow-up time were associated with nonfailure. Conversely, MMA diameter less than 1.5 mm (OR, 1.7; P = .044), midline shift (OR, 1.1; P = .02), and superselective MMA catheterization (without targeting the main MMA trunk) (OR, 2; P = .029) were associated with radiographic failure. Sensitivity analyses retained these associations. Conclusion Multiple independent predictors of failure of MMAE treatment for chronic subdural hematomas were identified, with small diameter (<1.5 mm) being the only factor independently associated with both clinical and radiographic failures. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Chaudhary and Gemmete in this issue.

Effect of postoperative tranexamic acid on recurrence rate and complications in chronic subdural hematomas patients: preliminary results of a randomized controlled clinical trial

Chronic subdural hematoma (CSDH) is a frequent neurosurgical disease which mainly affects elderly patients. Tranexamic acid (TXA) has been hypothesized as an oral agent to avoid CSDH progression and/or recurrence. We performed an evaluation to determine whether the postoperative use of TXA reduces recurrence rate. A prospective, randomized, and controlled trial. Patients with unilateral or bilateral chronic subdural hematoma undergoing surgical treatment by burr-hole were randomized as to whether or not to use TXA in the postoperative period. We evaluated image and clinical recurrence of CSDH at follow up of 6 months and potential clinical and/or surgical complications impact of TXA. Twenty-six patients were randomized to the control group (52%) and twenty-four patients to the TXA group (48%). Follow-up ranged from 3 to 16 months. There were no significant difference between baseline data in groups regarding to age, gender, use of antiplatelet or anticoagulants, smoking, alcoholism, systemic arterial hypertension, diabetes mellitus, hematoma laterality, hematoma thickness, and drain use. Clinical and radiological recurrence occurred in three patients (6%), being two cases in TXA group (8.3%) and 1 in control group (3.8%). Postoperative complications occurred in two patients during follow-up (4%), being both cases in TXA group (8.3%), and none in the control group. Although TXA group had a higher recurrence rate (8.3%), there was no statistically significant difference between the two groups. Moreover, TXA group had two complications while control group had no complications. Although limited by experimental nature of study and small sample, our current data suggest that TXA should not be used as a potential agent to avoid recurrences of CSDH and might increase complication odds.

Safety and radiologic clearance of chronic subdural hematoma after endovascular embolization using SQUID 18 in patients older than 80 years

The aim of the study was to evaluate radiographic clearance and clinical outcomes in patients over age 80 who undergo SQUID 18 embolization of the middle meningeal artery (MMA) for the management of chronic subdural hematoma (cSDH). From April 2020 to October 2021, data were obtained from patients with cSDH who underwent MMA embolization at our institution. Clinical and radiological data including pre-operative and last follow-up CT scans were analyzed. Six embolization procedures were performed in five patients using SQUID 18, a liquid embolic agent. The median age was 83 years, and three subjects were female. Two of the six cases were recurrent hematomas. MMA embolization was achieved in 100% of cases. The median diameter of the hematoma at admission was 20 mm and at last follow-up was 5.3 mm, demonstrating statistically significant radiographic clearance (P = 0.043). There were no intra or post-operative complications. Mortality was not noted during observation period. SQUID MMA embolization safely and significantly reduced the hematoma diameter and offers an alternative treatment in patients older than 80 years with cSDH.

Artificial cerebrospinal fluid use during burr-hole surgery and reoperation rate in patients with chronic subdural hematoma: an analysis using a nationwide inpatient database

BACKGROUND

The optimal surgical procedure to reduce the recurrence rate of chronic subdural hematoma (CSDH) after burr-hole surgery remains to be established. This study aimed to investigate the association between artificial cerebrospinal fluid (ACF) use during burr-hole surgery and reoperation rate in patients with CSDH.

METHOD

In this retrospective cohort study, we used the Japanese Diagnostic Procedure Combination inpatient database. We identified patients aged 40-90 years who were hospitalized for CSDH and had undergone burr-hole surgery within 2 days of admission, between July 1, 2010 and March 31, 2019. We performed a one-to-one propensity score-matched analysis to compare the outcomes between patients with and without ACF irrigation during burr-hole surgery. The primary outcome was reoperation within 1 year of surgery. The secondary outcome was the total hospitalization costs.

RESULTS

Of the 149,543 patients with CSDH from 1100 hospitals, ACF was used in 32,748 patients (21.9%). Propensity score matching created highly balanced 13,894 matched pairs. In the matched patients, the reoperation rate was significantly lower in the ACF users than that in the non-users group (6.3% vs. 7.0%, P = 0.015), with a risk difference of -0.8% (95% confidence interval, -1.5 to -0.2). There was no significant difference in the total hospitalization costs between the two groups (5079 vs. 5042 US dollars, P = 0.330).

CONCLUSIONS

ACF use during burr-hole surgery may be associated with lower reoperation rate in patients with CSDH.

Exhaustive drainage versus fixed-time drainage for chronic subdural hematoma after one-burr hole craniostomy (ECHO): study protocol for a multicenter randomized controlled trial

BACKGROUND

Chronic subdural hematomas (CSDHs) are one of the most common neurosurgical conditions. The standard surgical technique includes burr-hole craniostomy, followed by intraoperative irrigation and placement of subdural closed-system drainage. The drainage is generally removed after 48 h, which can be described as fixed-time drainage strategy. According to literature, the recurrence rate is 5-33% with this strategy. In our retrospective study, postoperative hematoma volume was found to significantly increase the risk of recurrence. Based on these results, an exhaustive drainage strategy is conducted to minimize postoperative hematoma volume and achieve a low recurrence rate and good outcomes.

METHODS

This is a prospective, multicenter, open-label, blinded endpoint randomized controlled trial designed to include 304 participants over the age of 18-90 years presenting with a symptomatic CSDH verified on cranial computed tomography or magnetic resonance imaging. Participants will be randomly allocated to perform exhaustive drainage (treatment group) or fixed-time drainage (control group) after a one-burr hole craniostomy. The primary endpoint will be recurrence indicating a reoperation within 6 months.

DISCUSSION

This study will validate the effect and safety of exhaustive drainage after one-burr hole craniostomy in reducing recurrence rates and provide critical information to improve CSDH surgical management.

TRIAL REGISTRATION

Clinicaltrials.gov, NCT04573387. Registered on October 5, 2020.

Single Frontal Burr-Hole Craniostomy Under Local Anesthesia for Treating Chronic Subdural Hematoma in the Septuagenarians and Older Adults: Surgical Technique and Results

Background Chronic subdural hematoma (CSDH) is not a totally benign disease in the elderly patients, especially those aged 70 years and above. Hence, the surgical treatment of CSDH in aged patients needs to be as minimally disruptive as possible.

Methods An annotated description of the surgical technique of single frontal burr-hole craniostomy performed under local anesthesia and without closed tube drainage for evacuating CSDH in the septuagenarians and older adults is given. We also review the outcome of the procedure on a prospective consecutive cohort of patients in our service

Results Thirty patients, 25 males, aged 70 years and above successfully underwent this surgical procedure. Their mean age was 76.5 years (standard deviation, 4.3). The CSDH was bilateral in 30% (9/30), and more left sided in the rest, the unilateral cases, and was of mixed density radiologically, in most cases (73%, 22/30). Clinical presentation was mainly gait impairment, cognitive decline, and headache, and 57% (17/30) presented with coma or stupor as assessed by the Markwalder grading scale.

The surgery was successfully executed in all, median duration 45.0 minutes (interquartile range 37.3–60.0), and solely under local anesthesia in 77% (23/30) or with momentary short-acting sedation in the rest. The outcome was very good in 90.0% (27/30) using the modified Rankin Scale (mRS) including two-third (20/30) completely asymptomatic (mRS 0) and 7/30 with only slight symptoms/disability, mRS ≤ 2. Three patients died perioperatively, all presenting in coma.

Conclusion This surgical technique appears very effectual for CSDH, is executed at a comparatively low cost, and, being much less disruptive than other traditional methods, may be a more homeostatic operative treatment in geriatric patients at least.

Surgical treatment for chronic subdural hematoma in the elderly: A retrospective analysis

Background

Chronic subdural hematoma (CSDH) is primarily a disease of the elderly. Less invasive interventions are often offered for elderly (> 80 years) patients due to concerns for elevated surgical risk, although data suggesting a clear outcome benefit is lacking.

Methods

All patients aged 65 years or older who underwent surgical treatment for CSDH at a single institution over a 4-year period were evaluated in this retrospective analysis. Surgical options included twist drill craniostomy (TDC), burr hole craniotomy (BHC), or standard craniotomy (SC). Outcomes, demographics, and clinical data were collected. Practice patterns and outcomes for patients older than 80 years old were compared to the age 65-80 cohort.

Results

110 patients received TDC, 35 received BHC, and 54 received SC. There was no significant difference in post-operative complications, outcomes, or late recurrence (30-90 days). Recurrence at 30 days was significantly higher for TDC (37.3% vs. 2.9% vs 16.7%, p 80 group, SC had higher risk of stroke and increased length of stay.

Conclusion

Twist drill craniostomy, burr hole craniostomy, and standard craniotomy have similar neurologic outcomes in elderly patients. Presence of thick membranes is a relative contra-indication for TDC due to high 30-day recurrence. Patients > 80 have higher risk of stroke and increased length of stay with SC.

Is a drainage time of less than 24 h sufficient after chronic subdural hematoma evacuation?

BACKGROUND

It is well established that the use of a postoperative drain after chronic subdural hematoma surgery reduces recurrence rates, and it is common to use a postoperative drain for longer than 24 h. It is unclear whether this is superior to a shorter drainage time of less than 24 h. Our aim was to compare a postoperative drainage longer or shorter than 24 h after chronic subdural hematoma evacuation.

MATERIALS AND METHODS

In this retrospective single centre study, 207 adult patients undergoing chronic subdural hematoma evacuation with a postoperative drainage longer (LDT-group) or shorter (SDT-group) than 24 h were compared regarding recurrence, mortality within 6 months and complications requiring hospital admission within 30 days. Length of hospital stay was also recorded. An active subgaleal drain was used. In addition to the retrospective cohort, we also studied the total volume drained per hour after cSDH surgery in a prospective cohort of 10 patients.

RESULTS

Recurrence occurred in 12/96 (12.5%) in the LDT-group and in 13/111 (11.7%) patients in the SDT-group (p = 0.15). There was no significant difference between groups regarding recurrence, complications or mortality. The prospective cohort showed that most of the drainage occurred within the first hours after surgery.

CONCLUSION

Our data show that a postoperative drainage duration of less than 24 h does not lead to an increase in recurrence, complications or mortality compared to a drainage time of more than 24 h. A shorter drainage duration (< 24 h) after cSDH surgery facilitated earlier mobilisation and shorter hospital stay.

A prospective randomized controlled trial of the effect of the number of burr hole on chronic subdural hematoma recurrence: An institutional experience

OBJECTIVE

The purpose of this study was to compare the effect of single burr hole (SBH) versus double burr hole (DBH) drainage on the recurrence rate of chronic subdural hematoma (CSDH).

METHOD

Forty-four patients undergoing burr hole craniostomy (BHC) between July 2022 and December 2022 were enrolled in a randomized clinical trial (RCT) comparing SBH to DBH surgeries. The primary endpoint of this study was the recurrence rate of CSDH. Radiological characteristics such as midline shift, thickness, volume, density, type of hematoma, brain atrophy and so on were secondary endpoints.

RESULTS

Forty-four patients participated in this study. Twenty-two hematomas underwent SBH craniostomy, and the other 22 had DBH craniostomy. The mean age in the SBH and DBH groups were 68.59 ± 7.94 and 69.54 ± 10.58, respectively. In each group, the proportion of males (SBH=16; DBH=15) was higher than that of females (SBH=6; DBH=7). The mean surgery time in the SBH group was significantly less than in the DBH group (p = 0.001). However, the two groups had no statistically significant difference in the CSDH recurrence rate (p = 0.312).

CONCLUSION

Our findings showed that SBH craniostomy is equally effective as DBH craniostomy at draining hematomas and does not increase the recurrence rate. Contrarily, the SBH craniostomy had a shorter surgical duration than the DBH craniostomy. As a result, we recommend SBH surgeries for all patients, with emphasis on the elderly and those with severe comorbidities, as well as in situations with few surgical facilities and a high patient admission rate.

Cortical atrophy in chronic subdural hematoma from ultra-structures to physical properties

Several theories have tried to elucidate the mechanisms behind the pathophysiology of chronic subdural hematoma (CSDH). However, this process is complex and remains mostly unknown. In this study we performed a retrospective randomised analysis comparing the cortical atrophy of 190 patients with unilateral CSDH, with 190 healthy controls. To evaluate the extent of cortical atrophy, CT scan images were utilised to develop an index that is the ratio of the maximum diameter sum of 3 cisterns divided by the maximum diameter of the skull at the temporal lobe level. Also, we reported, for the first time, the ultrastructural analyses of the CSDH using a combination of immunohistochemistry methods and transmission electron microscopy techniques. Internal validation was performed to confirm the assessment of the different degrees of cortical atrophy. Relative Cortical Atrophy Index (RCA index) refers to the sum of the maximum diameter of three cisterns (insular cistern, longitudinal cerebral fissure and cerebral sulci greatest) with the temporal bones' greatest internal distance. This index, strongly related to age in healthy controls, is positively correlated to the preoperative and post-operative maximum diameter of hematoma and the midline shift in CSDH patients. On the contrary, it negatively correlates to the Karnofsky Performance Status (KPS). The Area Under the Receiver Operating Characteristics (AUROC) showed that RCA index effectively differentiated cases from controls. Immunohistochemistry analysis showed that the newly formed CD-31 positive microvessels are higher in number than the CD34-positive microvessels in the CSDH inner membrane than in the outer membrane. Ultrastructural observations highlight the presence of a chronic inflammatory state mainly in the CSDH inner membrane. Integrating these results, we have obtained an etiopathogenetic model of CSDH. Cortical atrophy appears to be the triggering factor activating the cascade of transendothelial cellular filtration, inflammation, membrane formation and neovascularisation leading to the CSDH formation.

Adjuvant oral tranexamic acid and reoperation after burr hole surgery in patients with chronic subdural hematoma: propensity score-matched analysis using a nationwide inpatient database

OBJECTIVE

Adjuvant medical treatment to reduce the recurrence rate after burr hole surgery for chronic subdural hematoma (CSDH) has not yet been established. This study aimed to investigate the association between tranexamic acid (TXA) use after burr hole surgery and the reoperation rate in patients with CSDH.

METHODS

This observational study used the Japanese Diagnostic Procedure Combination inpatient database, a nationwide inpatient database in Japan, from July 1, 2010, to March 31, 2019. The authors identified patients who were hospitalized for CSDH and underwent burr hole surgery within 2 days of admission. The primary outcome measure was reoperation within 1 year after surgery. One-to-one propensity score-matched analysis was performed to compare the outcomes between patients who started oral TXA within 2 days after surgery (TXA users) and those who did not (TXA nonusers). Robustness of the analyses was assessed using the instrumental variable analysis.

RESULTS

Of the 149,543 patients with CSDH treated at 1100 hospitals, 7366 (4.9%) were TXA users. Propensity score matching created 6564 matched pairs with highly balanced baseline characteristics. The reoperation rate was significantly lower in TXA users than in nonusers (1.9% vs 6.1%, p < 0.001) with a risk difference of -4.1% (95% CI -4.8% to -3.4%). There was no significant difference in composite adverse events (0.6% vs 0.5%, p = 0.817). Total hospitalization costs were also significantly lower in TXA users than in nonusers ($5229 vs $5344 [USD], p < 0.001). The results of the instrumental variable analysis were consistent with those of the propensity score-matched analysis.

CONCLUSIONS

Findings of this study, using a nationwide inpatient database, suggest that adjuvant TXA use after burr hole surgery was associated with a reduced reoperation rate in patients with CSDH.

Subdural Hematomas in Adults and Children

Subdural hematoma is a common entity encountered by the neurosurgeon. The disease has acute, subacute, and chronic forms. Management of the disease changes according to the etiology of the lesion, yet the main goals are, as with most neurosurgical interventions, decompression of neural tissue and restoration of perfusion. Due to various forms and causes of the disease such as trauma, anticoagulant/antiaggregant use, arterial rupture, oncologic hemorrhages, intracranial hypotension, and idiopathic hemorrhages, several approaches for management have been documented in the literature. Herewith, we present various up-to-date management options for the disease.

Effect of Irrigation Fluid Temperature on Recurrence in the Evacuation of Chronic Subdural Hematoma: A Randomized Clinical Trial

Importance

The effect of a physical property of irrigation fluid (at body vs room temperature) on recurrence rate in the evacuation of chronic subdural hematoma (cSDH) needs further study.

Objective

To explore whether irrigation fluid temperature has an influence on cSDH recurrence.

Design, Setting, and Participants

This was a multicenter randomized clinical trial performed between March 16, 2016, and May 30, 2020. The follow-up period was 6 months. The study was conducted at 3 neurosurgical departments in Sweden. All patients older than 18 years undergoing cSDH evacuation during the study period were screened for eligibility in the study.

Interventions

The study participants were randomly assigned by 1:1 block randomization to the cSDH evacuation procedure with irrigation fluid at room temperature (RT group) or at body temperature (BT group).

Main Outcomes and Measures

The primary end point was recurrence requiring reoperation within 6 months. Secondary end points were mortality, health-related quality of life, and complication frequency.

Results

At 6 months after surgery, 541 patients (mean [SD] age, 75.8 [9.8] years; 395 men [73%]) had a complete follow-up according to protocol. There were 39 of 277 recurrences (14%) requiring reoperation in the RT group, compared with 16 of 264 recurrences (6%) in the BT group (odds ratio, 2.56; 95% CI, 1.38-4.66; P < .001). There were no significant differences in mortality, health-related quality of life, or complication frequency.

Conclusions and Relevance

In this study, irrigation at body temperature was superior to irrigation at room temperature in terms of fewer recurrences. This is a simple, safe, and readily available technique to optimize outcome in patients with cSDH. When irrigation is used in cSDH surgery, irrigation fluid at body temperature should be considered standard of care.

Trial Registration

ClincalTrials.gov Identifier: NCT02757235.

Early spontaneous cessation of subdural drainage after burr hole evacuation of chronic subdural hematoma and risk of recurrence

OBJECTIVE

Subdural drainage reduces recurrence after evacuation of chronic subdural hematoma (CSDH). In the present study, the authors investigated the dynamics of drain production and potentially contributing factors for recurrence.

METHOD

Patients treated with a single burr hole evacuation of CSDH between April 2019 and July 2020 were included. Patients were also participants in a randomized controlled trial. All patients included, had a passive subdural drain for exactly 24 hours. Drain production, Glasgow Coma Scale score, and degree of mobilization was recorded every hour for 24 hours. A CSDH successfully drained for 24 hours is referred to as a "case". Patients were followed for 90 days. Primary outcome was symptomatic recurrent CSDH requiring surgery.

RESULTS

A total of 118 cases from 99 patients were included in the study. Of the 118 cases, 34 (29%) had spontaneous drain cessation within the first 0-8 hours after surgery (Group A), 32 (27%) within 9-16 hours (Group B), and 52 (44%) within 17-24 hours (Group C). Hours of production (P < 0.000) and total drain volume (P = 0.001) were significantly different between groups. The recurrence rate was 26.5% in group A, 15.6% in group B, and 9.6% in group C (P = 0.037). Multivariable logistic regression analysis show that cases in group C (OR: 0.13, P = 0.005) are significantly less likely to recur compared to group A. Only in 8 of the 118 cases (6.8%), the drain started draining again after an interval of three consecutive hours.

CONCLUSIONS

Early spontaneous cessation of subdural drain production seems to be associated with increased risk of recurrent hematoma. Patients with early cessation of drainage did not benefit from further drain time. Observations of the present study indicate personalized drainage discontinuation strategy as a potentially alternative to a specific discontinuation time for all CSDH patients.

Middle Meningeal Artery Embolization for the Management of Chronic Subdural Hematomas: A New-Old Treatment

Chronic subdural hematoma (cSDH) is defined as a subdural collection of blood on CT imaging that tends to persist and gradually increase in volume over time, with components that are hypodense or isodense compared to the brain. There are no proven guidelines for the management of patients with cSDH. Surgical approaches included burr hole, twist drill hole, and craniotomy-based evacuations. Outcomes after surgical removal is generally favorable, but cSDH tends to recur after the initial evacuation.Middle meningeal artery (MMA) embolization has been gaining increasing popularity among the treatments of cSDH. This is largely due to a growing population of patients with cSDH who are refractory to other treatments or in patients who present with multiple comorbidities or who are taking antiplatelet and anticoagulant medications. The goal of middle meningeal artery (MMA) embolization is to devascularize subdural membranes associated with SDH so that the balance between continued leakage and reabsorption is shifted toward reabsorption.We discuss our clinical and technical approach to cSDH treated with perioperative embolization of the MMA.

A bibliometric analysis of chronic subdural hematoma since the twenty-first century

BACKGROUND

Chronic subdural hematoma (CSDH) is a common disease that forms between the dura and arachnoid membranes of the brain. With the development of medications and surgery, significant progress has been made in the diagnosis and treatment of CSDH. However, there is no comprehensive analysis available on CSDH-related studies published in the literature. This study aimed to collect and analyze CSDH-related studies published since the twenty-first century using bibliometric analysis and to summarize the current status of research in this field for the sake of providing systematic data for further study of CSDH.

METHODS

CSDH-related studies were searched in the Web of Science Core Collection (WoSCC) database using the Medical Subject Heading (MeSH) term 'chronic subdural hematoma'. Data analysis and visualization were performed by R and CiteSpace software.

RESULTS

This study retrieved 1424 CSDH-related articles published since the beginning of the twenty-first century. There was a general increase in both the number of published articles and the mean number of citations. The authors, institutions and journals that contributed the most to the field of CSDH were Jianning Zhang, Tianjin Medical University, and world neurosurgery, respectively. The reference co-citation network identified 13 clusters with significant modularity Q scores and silhouette scores (Q = 0.7124, S = 0.8536). The major research categories were (1) evolution of the therapeutic method and (2) the etiology and pathology of CSDH. Keyword analysis revealed that 'middle meningeal artery embolization' was the latest burst keyword.

CONCLUSIONS

This study identified the most influential countries, authors, institutions and journals contributing to CSDH research and discussed the hotspots and the latest subjects of CSDH research.

Nationwide Readmission Rates and Hospital Charges for Patients With Surgical Evacuation of Nontraumatic Subdural Hematomas: Part 2-Burr Hole Craniostomy

BACKGROUND

Nontraumatic subdural hematoma (SDH) is a common neurological disease that causes extensive morbidity and mortality. Craniotomy or burr hole craniostomy (BHC) is indicated for symptomatic lesions, but both are associated with high recurrence rates. Although extensive research exists on postoperative complications after BHCs, few studies have examined the underlying causes and predictors of unplanned 30-day hospital readmissions at the national level.

OBJECTIVE

To compare causes for hospital readmission within 30 days after surgical SDH evacuation with BHC and evaluate readmission rates and independent predictors of readmission.

METHODS

This retrospective cohort observational study was designed using the Nationwide Readmissions Database. We identified patients who had undergone BHC for SDH evacuation (2010-2015). National estimates and variances within the cohort were calculated after stratifying, hospital clustering, and weighting variables.

RESULTS

We analyzed 2753 patients who had BHC for SDH evacuation: 675 (24.5%) had at least one 30-day readmission. Annual readmission rates did not vary across the study period ( P = .60). The most common cause of readmission was recurrent SDH (n = 630, 93.3%), and the next most common was postoperative infection (n = 12, 1.8%). Comorbidities significantly associated with readmission included fluid and electrolyte disorders, chronic blood loss anemia, chronic obstructive pulmonary disease, depression, liver disease, and psychosis ( P ≤ .04), but statistically significant independent predictors for readmission included only chronic obstructive pulmonary disease and fluid and electrolyte disorders ( P ≤ .007).

CONCLUSION

These national trends in 30-day readmission rates after nontraumatic SDH evacuation by BHC not otherwise published provide quality benchmarks that can aid national quality improvement efforts.

Middle Meningeal Artery Embolization Minimizes Burdensome Recurrence Rates After Newly Diagnosed Chronic Subdural Hematoma Evacuation (MEMBRANE): study protocol for a randomized controlled trial

Background

Chronic subdural hematoma (cSDH) is the most common complication of mild traumatic brain injury demanding neurosurgery in high-income countries. If undetected and untreated, cSDH may increase intracranial pressure and cause neurological deficiencies. The first-line intervention of choice is burr hole trepanation and hematoma evacuation. However, any third patient may experience rebleeding, demanding craniotomy with excess morbidity. Adjunct endovascular embolization of the frontal and parietal branches of the middle meningeal artery (MMA) is a promising approach to avoid relapse and revision but was hitherto not studied in a randomized trial.

Methods

MEMBRANE is an investigator-initiated, single-center, randomized controlled trial. Male, female, and diverse patients older than 18 years scheduled for surgical evacuation of a first cSDH will be assigned in a 1:1 fashion by block randomization to the intervention (surgery plus endovascular MMA embolization) or the control group (surgery alone). The primary trial endpoint is cSDH recurrence within 3 months of follow-up after surgery. Secondary endpoints comprise neurological deficits assessed by the modified Rankin Scale (mRS) and recurrence- or intervention-associated complications during 3 months of follow-up. Assuming a risk difference of 20% of rebleeding and surgical revision, a power of 80%, and a drop-out rate of 10%, 154 patients will be enrolled onto this trial, employing an adaptive O’Brien-Fleming approach with a planned interim analysis halfway.

Discussion

The MEMBRANE trial will provide first clinical experimental evidence on the effectiveness of endovascular embolization of the MMA as an adjunct to surgery to reduce the risk of recurrence after the evacuation of cSDH.

Trial registration

German Clinical Trials Registry (Deutsches Register Klinischer Studien [DRKS]) DRKS00020465. Registered on 18 Nov 2021. ClinicalTrials.gov NCT05327933. Registered on 13 Apr 2022.

[Middle meningeal artery embolization for chronic subdural hematomas]

The treatment of chronic subdural hematoma (cSDH) represents a challenge due to high recurrence rates (2-37%). One possible treatment option is middle meningeal artery (MMA) embolization as an alternative to surgery. In contrast to acute SDH, which is caused by a rupture of the bridging veins, cSDH has a different pathomechanism. Injury to the so-called dural boundary cell layer results in an intermittent or continuous cycle of cell proliferation, angiogenesis, secretion, and bleeding due to rupture of newly formed vessels within the SDH membrane. This membrane is supplied by the MMA. Embolization of the MMA leads to resorption of the cSDH. The results published so far regarding MMA embolization as sole therapy or in combination with surgical treatment are encouraging with a long-term success rate of up to 90%.

Establishment and validation of a prediction model for self-absorption probability of chronic subdural hematoma

Background

Chronic subdural hematoma (CSDH) is common in elderly people with a clear or occult traumatic brain injury history. Surgery is a traditional method to remove the hematomas, but it carries a significant risk of recurrence and poor outcomes. Non-surgical treatment has been recently considered effective and safe for some patients with CSDH. However, it is a challenge to speculate which part of patients could obtain benefits from non-surgical treatment.

Objective

To establish and validate a new prediction model of self-absorption probability with chronic subdural hematoma.

Method

The prediction model was established based on the data from a randomized clinical trial, which enrolled 196 patients with CSDH from February 2014 to November 2015. The following subjects were extracted: demographic characteristics, medical history, hematoma characters in imaging at admission, and clinical assessments. The outcome was self-absorption at the 8th week after admission. A least absolute shrinkage and selection operator (LASSO) regression model was implemented for data dimensionality reduction and feature selection. Multivariable logistic regression was adopted to establish the model, while the experimental results were presented by nomogram. Discrimination, calibration, and clinical usefulness were used to evaluate the performance of the nomogram. A total of 60 consecutive patients were involved in the external validation, which enrolled in a proof-of-concept clinical trial from July 2014 to December 2018.

Results

Diabetes mellitus history, hematoma volume at admission, presence of basal ganglia suppression, presence of septate hematoma, and usage of atorvastatin were the strongest predictors of self-absorption. The model had good discrimination [area under the curve (AUC), 0.713 (95% CI, 0.637–0.788)] and good calibration (p = 0.986). The nomogram in the validation cohort still had good discrimination [AUC, 0.709 (95% CI, 0.574–0.844)] and good calibration (p = 0.441). A decision curve analysis proved that the nomogram was clinically effective.

Conclusions

This prediction model can be used to obtain self-absorption probability in patients with CSDH, assisting in guiding the choice of therapy, whether they undergo non-surgical treatment or surgery.

Recent Advances and Future Directions in Middle Meningeal Artery Embolization for Chronic Subdural Hematomas

PURPOSE OF REVIEW

The purpose of this review is to present a brief background on chronic subdural hematomas (cSDH), middle meningeal artery (MMA) embolization, and its role in decreasing recurrence of cSDH. A review of the most up-to-date literature should demonstrate the efficacy of this procedure.

RECENT FINDINGS

The latest data shows that MMA embolization is a safe procedure, with low complication rates and low recurrence rates. While cSDH managed with surgical evacuation can have a recurrence rate upwards of 30%, MMA embolization alone or as an adjunct to surgery decreases recurrence to less than 5% in most studies. MMA embolization can be especially useful in high-risk populations such as the elderly, patients on anti-platelet medication, and those with coagulopathies. It can also be done awake, done without general anesthesia, and is significantly less invasive than traditional surgical techniques. In reviewing the literature on MMA embolization, it is clear that there are numerous retrospective studies and systematic reviews demonstrating its safety and efficacy, and some prospective dual-arm studies that present novel information. The numerous clinical trials that are currently underway should help to further establish MMA embolization as standard of care in the management of cSDH.