Chronic subdural hematoma case series

A retrospective study included cases performed at a Level II Trauma Center between January 2019 and December 2020 for MMAE of cSDHs. Data collected included patient demographic characteristics and comorbidities, SDH characteristics, complications, and efficacy outcomes. The lesion measurements were collected before the procedure, 4-6 weeks and 3-6 months post-procedure.

Results: In our patient population, 78% (39) either had lesions improve or completely resolved. The sample included 50 patients with a mean age of 74 years old. Statistically significant reductions in lesion size were found from pre- to post-procedure in the left lesions, right lesions, and midline shifts. The left lesions decreased from 13.88 ± 5.70 mm to 3.19 ± 4.89 mm at 3-6 months with P < 0.001. The right lesions decreased from 13.74 ± 5.28 mm to 4.93 ± 7.46 mm at 3-6 months with P = 0.02. Midline shifts decreased from 3.78 ± 3.98 mm to 0.48 ± 1.31 mm at 3-6 months with P = 0.02. No complications were experienced for bleeding, hematoma, worsening SDH, pseudoaneurysm, or stroke.

The pilot study from a single center utilizing MMAE demonstrates that MMAE is successful without increasing treatment-related complications not only for cSDH but also in acute-on-cSDH and SDH with a subacute component ¹⁾.

From a prospective registry, Burr hole trephination for chronic subdural hematoma carried out under the protocol (including early thromboprophylaxis, no flat bed rest, early mobilization without drain clamping, and early resumption of antithrombotic medication) were extracted, along with those procedures carried out within the past year before protocol change. Propensity score-based matching was carried out. A range of clinical and imaging outcomes were analyzed, including modified Rankin Scale as effectiveness and Clavien-Dindo adverse event grading as safety primary end points.

Results: Per group, 91 procedures were analyzed. At discharge, there was no significant difference in the modified Rankin Scale among the standard and enhanced recovery groups (1 [1; 2] vs 1 [1; 3], P = .552), or in Clavien-Dindo adverse event grading classifications of adverse events (P = .282) or occurrence of any adverse events (15.4% vs 20.9%, P = .442). There were no significant differences in time to drain removal (2.00 [2.00; 2.00] vs 2.00 [1.25; 2.00] days, P = .058), time from procedure to discharge (4.0 [3.0; 6.0] vs 4.0 [3.0; 6.0] days, P = .201), or total hospital length of stay (6.0 [5.0; 9.0] vs 5.0 [4.0; 8.0] days, P = .113). All-cause mortality was similar in both groups (8.8% vs 4.4%, P = .289), as was discharge disposition (P = .192). Other clinical and imaging outcomes were similar too (all P > .05).

Conclusion: In a matched cohort study comparing perioperative standard of care with a novel enhanced recovery protocol focusing on evidence-based drainage, mobilization, and thromboprophylaxis regimens as well as changes to the standardized reuptake of oral anticoagulants and antiaggregants, no differences in safety or effectiveness were observed after burr hole evacuation of cSDH ²⁾.

Sayed et al. conducted a large retrospective cohort study of patients who underwent a cSDH evacuation at a single urban institution between 2015 and 2022. Data were collected from the electronic medical record on prior comorbidities, anticoagulation use, mental status on presentation, preoperative labs, and preoperative/postoperative imaging parameters. Univariate and multivariate analyses were conducted to analyze predictors of mortality. Mortality during admission for this cohort was 6.1%. Univariate analysis showed the mortality rate was higher in those presenting with a history of dialysis. In addition, those who presented with altered mental status were intubated, and lower GCS scores had higher rates of POM. Usage of Coumadin was correlated with higher rates of POM. Examination of preoperative labs showed that patients who presented with anemia or thrombocytopenia had higher POM. Imaging data showed that cSDH volume and greatest dimension were correlated with higher rates of POM. Finally, patients who were not extubated postoperatively had higher rates of POM. Multivariate analysis showed that only altered mental status and not being extubated postoperatively were correlated with a higher risk of mortality. In summation, they demonstrated that altered mental status and failure to extubate were independent predictors of mortality in cSDH evacuation. Interestingly, patient age was not a significant predictor of mortality ³⁾.

Jeon et al. retrospectively evaluated 578 consecutive patients who underwent single burr hole surgery for chronic SDH at our institute between January 2008 and December 2021. Various clinical and radiological factors in patients with and without recurrence were compared using univariate and multivariate logistic regression analyses. A total of 438 patients (531 hemispheres) were analyzed. Fifty-four (10.17%) of the 531 hemispheres had recurrence of chronic SDH within 6 months. Male sex (adjusted odds ratio (aOR) = 3.48; 95% confidence interval (CI), 1.42-8.49), bilateral hematomas (aOR = 2.14; 95% CI, 1.05-4.35), laminar hematoma type (aOR = 2.87; 95% CI, 1.23-6.71), > 30-cm3 volume of postoperative residual hematoma (aOR = 2.99; 95% CI, 1.01-8.83), and preoperative blood glucose level of ≥ 150 mg/dL (aOR = 2.11; 95% CI, 1.10-4.05) were identified as independent factors associated with recurrence in multivariate logistic regression analysis. The present study revealed that male patients and those who had bilateral hematomas, laminar hematoma type, a large volume of hematoma after surgery, and a high preoperative blood glucose level had a higher probability of experiencing recurrent chronic SDH. We recommend close monitoring of patients 6 months postoperatively to detect subsequent chronic SDH recurrence ⁴⁾

A study conducted at the Sri Ramachandra Institute of Higher Education and Research between 2017 and 2021 presents valuable insights into the recurrence of chronic subdural hematoma (CSDH) following surgical intervention. The combination of prospective and retrospective design provides a comprehensive view of patient outcomes, contributing to a deeper understanding of factors influencing CSDH recurrence.

The fact that the study received ethical approval from the Institutional Ethics Committee ensures that the research was conducted in accordance with ethical standards, safeguarding the welfare of the patients involved.

The study's focus on assessing patients who underwent surgery for CSDH, particularly those experiencing recurrence, addresses an important clinical concern. The finding of an average age difference between patients with recurrence and those without is noteworthy, even though the lack of a significant statistical correlation suggests that age alone might not be a robust predictor of recurrence.

The significant male predominance observed in CSDH recurrence is an interesting finding, with a statistically significant p-value indicating a clear gender disparity. This observation raises questions about potential underlying factors contributing to this discrepancy and warrants further investigation.

The utilization of multivariate analysis to identify heterogenous subtypes as a significant predictor of recurrence adds depth to the study's findings. The reported odds ratio and confidence interval provide quantitative insights into the strength of this association.

The statistically significant correlation between the mean midline shift and CSDH recurrence underscores the importance of radiological factors in predicting and managing recurrence risk. This finding highlights the clinical significance of midline shift measurements in guiding treatment decisions.

The description of the surgical approaches undertaken for evacuation provides valuable clinical context. The use of burr holes, placement of subdural drains, and the consideration of mini-craniotomy offer insights into the diverse strategies employed for managing recurrent CSDH cases.

The identification of refractory CSDH cases and their management using a second evacuation using burr holes and, in some cases, craniotomy, highlights the complexities that clinicians face when dealing with challenging cases.

In conclusion, the study contributes to our understanding of chronic subdural hematoma recurrence and its associated factors. The emphasis on patient-related and radiological factors as potential predictors of recurrence offers clinicians valuable guidance in identifying high-risk cases. The study's findings provide a foundation for further research, potentially leading to more tailored treatment approaches and improved patient outcomes in the future. ⁵⁾.

A retrospective study of Orscelik et al. provides valuable insights into the combination of middle meningeal artery (MMA) embolization using polyvinyl alcohol particles and surgical evacuation for the treatment of chronic subdural hematomas (cSDHs). The study's focus on both primary and secondary outcomes sheds light on the potential benefits and safety profile of this treatment approach.

The fact that the study was conducted at a single center provides a consistent treatment protocol and patient population, which can be advantageous for drawing meaningful conclusions from the results. The primary outcome of recurrence requiring surgical intervention, along with the secondary outcomes of reduction in cSDH size, complications, and improvement in modified Rankin scale (mRS) score, collectively offer a comprehensive assessment of the treatment's effectiveness.

The results indicate a high success rate, with a substantial majority of cases (93.3%) achieving significant reduction in cSDH size. The recurrence rate requiring surgical rescue (6.7%) is relatively low, suggesting that the combination of MMA embolization and surgical evacuation has the potential to mitigate the risk of cSDH recurrence.

The reported complications related to the embolization procedure (6.0%) are within a reasonable range considering the complexity of the intervention. However, further details about the nature and severity of these complications would provide a more nuanced understanding of the safety profile.

The improvement in modified Rankin scale (mRS) scores for a significant proportion of patients (78.4%) is an encouraging finding, indicating a positive impact on their functional outcomes and quality of life.

One mortality (2%) reported, regardless of the embolization and evacuation, underscores the seriousness of the condition and the importance of continued research to refine treatment approaches and minimize risks.

In conclusion, the study suggests that the combination of MMA embolization and surgical evacuation can be a safe and effective approach for reducing the size and recurrence of chronic subdural hematomas. However, as with any retrospective study, there are limitations, such as the lack of randomization and potential biases. While the findings are promising, further research through prospective studies and larger cohorts will be valuable to validate these results and provide more comprehensive insights into the long-term outcomes and potential benefits of this combined treatment strategy. ⁶⁾.

A prospective research conducted on individuals who underwent surgical intervention for chronic subdural hematoma (CSH) at the neurosurgery department presents important insights into the management and outcomes of this condition. The study's focus on various factors, including patient characteristics, medical history, medication usage, and radiological assessments, provides a comprehensive understanding of the factors influencing CSH treatment and recovery.

Enrolling 66 patients who underwent surgical intervention for CSH, whether as outpatients or in emergency settings, adds to the study's robustness by encompassing a range of cases and clinical scenarios. The utilization of the Glasgow Coma Scale (GCS) to assess neurological deficits and computed tomography (CT) to characterize the hematoma ensures a standardized and objective evaluation of the patients' conditions.

The division of patients into groups based on dexamethasone usage, as well as the statistical analysis of variance (ANOVA), provides a methodical approach to investigating the impact of this medication on patient outcomes. The finding of a statistical difference in the second week after the operation suggests a potential influence of dexamethasone on postoperative recovery. However, without further elaboration on the nature of the difference, it's challenging to draw precise conclusions about the clinical significance of this finding.

The differentiation between radiological membrane and subdural dimensions and the identification of a statistically significant correlation between anticoagulation and hematoma type are intriguing findings. These findings could point toward specific mechanisms or associations relevant to CSH management and outcomes.

The study's conclusion that dexamethasone was not associated with adverse events and could potentially help prevent reoperation in elderly patients with comorbidities is noteworthy. However, the precise mechanisms through which dexamethasone could exert such effects are not explicitly discussed in the summary.

In conclusion, the research contributes valuable insights into the management of chronic subdural hematoma and its associated factors. The study's strengths lie in its prospective design, comprehensive patient assessment, and statistical analyses. To enhance the impact of the study, it would be beneficial to provide more detailed information about the observed differences in the second week after the operation and the potential mechanisms through which dexamethasone could influence patient outcomes. ⁷⁾.

A study, conducted between April 2017 and July 2019, evaluates the effectiveness of Kampo medicine in reducing the recurrence rate of chronic subdural hematoma (CSDH) after initial burr hole surgery. The randomized assignment of patients into different groups and the focus on primary and secondary endpoints provide a structured approach to understanding the impact of Kampo medicine in this context.

The inclusion of 118 patients who underwent initial burr hole surgery and were randomly assigned to three distinct groups - Goreisan, Saireito, and no medication - offers a robust design to assess the efficacy of Kampo medicine. This randomization helps control potential biases and contributes to the validity of the study's findings.

The primary endpoint, symptomatic recurrence within 3 months postoperatively, is a clinically relevant measure for assessing the effectiveness of the interventions. The secondary endpoint of complications associated with Kampo medicine administration is also crucial for evaluating the safety of the treatments.

The study's findings indicate a noteworthy trend in recurrence rates. The lower recurrence rates observed in the Goreisan and Saireito groups compared to the no-medication group suggest a potential benefit of Kampo medicine in reducing CSDH recurrence. These differences are statistically significant, lending further weight to the conclusions drawn.

The discussion of the specific components of the Kampo medicine used, including the mention of byakujutsu (containing Atractylodes rhizome) and its potential anti-inflammatory properties, provides an important context for interpreting the study's results. This differentiation from other studies that used different compositions of Kampo medicine emphasizes the importance of understanding the specific constituents and their effects.

The conclusion that this study is the first to show that Kampo medicine can reduce the recurrence rate of CSDH is significant. If substantiated through further research and studies, this finding could have meaningful implications for improving the management and outcomes of patients with CSDH.

In summary, the study adds valuable insights to the understanding of Kampo medicine's potential role in reducing CSDH recurrence after initial surgical intervention. The well-designed randomized approach, statistically significant findings, and consideration of specific medicine compositions make this research a promising step toward potentially enhancing the treatment of chronic subdural hematoma. However, as with any study, it's important to consider the limitations and the need for further research to confirm and extend these findings ⁸⁾.

A retrospective cohort study contributes valuable insights into the relationship between frailty, as measured by the mFI-5 score, and outcomes following surgical evacuation of chronic subdural hematoma (cSDH). The utilization of the mFI-5 score to stratify patients into different frailty categories allows for a nuanced examination of the impact of frailty on various outcomes. The application of multivariate Cox proportional hazards regression analysis adds a robust statistical approach to identify factors associated with primary and secondary outcomes.

The study's inclusion of 118 patients with a mean age of 74.4 years presents a relevant and representative population for investigating the outcomes of interest. The uniformity of baseline demographics across the different frailty groups helps ensure that any observed differences are more likely attributed to frailty status rather than confounding factors.

The findings of the study, as revealed through the multivariate analysis, highlight the significant influence of severe frailty on various outcomes. The increased rates of 30-day readmission, postoperative mortality, non-home disposition, development of new post-operative neurologic deficits, hematoma reaccumulation, and the novel scoring system's predictive value for 90-day mortality collectively emphasize the importance of considering frailty in predicting surgical outcomes for cSDH patients.

The novel scoring system incorporating both patient age and frailty status further contributes to the understanding of predictive factors for mortality, enhancing the study's potential clinical implications. The relatively high area under the curve (AUC) of 0.77 for the scoring system suggests its potential utility in risk assessment.

In conclusion, the study underscores the significance of frailty, as measured by the mFI-5 score, in predicting outcomes following surgical evacuation of chronic subdural hematoma. The findings provide valuable information for clinicians to consider when evaluating and managing cSDH patients. The study's robust methodology and meaningful results contribute to the growing body of knowledge regarding the impact of frailty on surgical outcomes and highlight the potential of the mFI-5 score and the novel scoring system as tools for risk assessment in this context. However, as with any study, it's important to acknowledge potential limitations and the need for further research to validate and build upon these findings ⁹⁾.

In a retrospective study, consecutive CSDH patients with postcontrast DECT head images from January 2020 and June 2021 were analyzed. Predictor variables derived from DECT were correlated with outcome variables followed by mixed-effects regression analysis.

The study included 36 patients with 50 observations (mean age, 72.6 years; standard deviation, 11.6 years); 31 were men. Dual-energy CT variables that correlated with hematoma volume were external membrane volume (ρ, 0.37; P = 0.008) and iodine concentration (ρ, -0.29; P = 0.04). Variables that correlated with the separated type of hematoma were total iodine leak (median [Q1, Q3], 68.3 mg [48.5, 88.9] vs 38.8 mg [15.5, 62.9]; P = 0.001) and iodine leak per unit membrane volume (median [Q1, Q3], 16.47 mg/mL [10.19, 20.65] vs 8.68 mg/mL [5.72, 11.41]; P = 0.002). Membrane grade was the only variable that correlated with fractional hyperdense hematoma (ρ, 0.28; P = 0.05). Regression analysis showed total iodine leak as the strongest predictor of separated type hematoma (odds ratio [95% confidence interval], 1.06 per mg [1.01, 1.1]).

Dual-energy CT demonstrates iodine leak from CSDH membranes. The variables derived from DECT correlated with hematoma volume, internal architecture, and fractional hyperdense hematoma ¹⁰⁾.

92 patients from Gaziosmanpasa Training and Research Hospital in Istanbul who were operated after diagnosis of Chronic Subdural Hematoma between April 1, 2015 and July 1, 2021 were reviewed retrospectively. Preoperative and postoperative computerized tomography (CT) scans were scrutinized and the thickness of hematoma and midline shift and the diameters of two burr holes opened were measured and recorded. The correlation between burr hole diameter width and chronic subdural hematoma thickness in postoperative CT and improvement in midline shift was investigated statistically.

When the CT scans performed on the postoperative 1st day and postoperative 1st month were examined, it was determined that the preoperative hematoma thickness and midline shift were significantly reduced (p<0.001). A positive significant correlation was found between the improvement of the midline shift, the posterior burr hole diameter and the anterior-posterior burr hole arithmetic mean (p<0.001; p=0.029, respectively).

Having examined the current surgical treatment techniques in the treatment of chronic subdural hematoma, they found that an increase in the width of burr hole craniotomies (BHC), especially the posterior BHC, contributed to the improvement in midline shift ¹¹⁾.

The clinical data of CSDH patients who underwent surgery between March 2018 and June 2020 in the Department of Neurosurgery of the First Affiliated Hospital of Xiamen University were retrospectively collected and analyzed. Eighty patients with CSDH who met the inclusive criteria were selected. A control group (32 cases treated with burr hole drainage) and an observation group (48 cases treated with neuroendoscopy-assisted surgery) were set according to different operation methods. The hematoma clearance rate, surgery-related indicators, related complications, hematoma recurrence rate and related prognostic indicators of the two groups were compared and analyzed.

The postoperative hematoma clearance rate of the observation group was 92.59%, which was higher than that of the control group (77.78%) (P<0.05). The operation time of the observation group was longer than that of the control group (P<0.05). The postoperative hospitalization time of the observation group was shorter than that of the control group (P<0.05). The postoperative complication rate of the observation group was lower than that of the control group (P<0.05). The recurrence rate of hematoma in the observation group in the six-month postoperative follow-up was 1.85%, which was lower than that in the control group (P<0.05). The limb motor function and daily living ability score of the observation group were higher than those of the control group, and the Markwalder grading score was lower than that of the control group (P<0.05).

Neuroendoscopy-assisted treatment which is safe and effective is superior to traditional burr-hole drainage surgery. It can reduce the recurrence rate; thus, it is worth advocating and applying ¹²⁾.

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 trephination, 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.

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 a higher risk of stroke and increased length of stay.

Twist drill craniostomy, Burr hole trephination, and standard craniotomy have similar neurologic outcomes in elderly patients. The presence of thick membranes is a relative contra-indication for Twist drill craniostomy due to high 30-day recurrence. Patients > 80 have a higher risk of stroke and increased length of stay with standard craniotomy ¹³⁾.

A total of 102 patients (mean age: 69 years; range: 21-100 years; male: 79) with CSDH underwent surgical drainage with repeat surgery in 13.7% of the patients (n=14). Peri-procedural mortality and morbidity were 11.8%(n=12) and 19.6% (n=20), respectively. Overall, among our patient population, recurrence was seen in 22.55% (n=23). The mean total hospital stay was 10.6 days. The retrospective cohort study showed an institutional CSDH recurrence risk of 22.55%, in keeping with what is reported in the literature. This baseline information is important for a Canadian setting and provides a basis for comparison for future Canadian trials ¹⁴⁾

In total, 93 patients with CSDH (71.0% male) with a mean age of 71.0 years were included. The mean CSDH thickness and midline shift were 19.7 and 9.8 mm, respectively. The mean levels of HO-1, ferritin, total bilirubin, white blood cells, segmented neutrophils, lymphocytes, platelets, international normalized ratio, and partial thromboplastin time were 36 ng/mL, 14.8 μg/mL, 10.5 mg/dL, 10.3 × 103 cells/μL, 69%, 21.7%, 221.1 × 109 cells/μL, 1.0, and 27.8 seconds, respectively. Pearson correlation analysis revealed that CSDH thickness was positively correlated with midline shift distance (r = 0.218, p < 0.05) but negatively correlated with HO-1 concentration (r = -0.364, p < 0.01) and ferritin level (r = -0.222, p < 0.05). Multivariate linear regression analysis revealed that HO-1 was an independent predictor of CSDH thickness (β = -0.084, p = 0.006). The angiogenic potency of HO-1 in hematoma fluid was tested with the chick CAM assay; topical addition of CSDH fluid with low HO-1 levels promoted neovascularization and microvascular leakage. Addition of HO-1 in a rescue experiment inhibited CSDH fluid-mediated angiogenesis and microvascular leakage.

HO-1 is an independent risk factor in CSDH hematomas and is negatively correlated with CSDH thickness. HO-1 may play a role in the chronic subdural hematoma pathophysiology and development of CSDH, possibly by preventing neovascularization and reducing capillary fragility and hyperpermeability ¹⁵⁾

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.

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 ¹⁶⁾.

Patients with mildly symptomatic CSDH treated with MMAE alone between July 2020 and June 2022 were examined. Neurological examinations and head CT scans were performed before treatment and 1, 7, 14, and 28 days after treatment. The clinical course of the patients was analyzed. In particular, symptom improvement within 1 week from treatment or rescue evacuation (RE) and the factors associated were evaluated.

Results: Fifteen patients were included in this study. No procedure-related complications occurred. Partial or complete recovery within the first week from treatment was observed in 10 cases (66.7%), and the symptoms resolved completely in a median of 26 (6.5-33.5) days. RE was needed in three cases (20.0%). The hematoma volume and midline shift gradually decreased from baseline, with a significant improvement within the first week (p=0.030 and 0.0032, respectively).

MMAE alone provides a relatively early improvement in cases of mildly symptomatic CSDH and may be a potential alternative to surgical evacuation or medical therapy ¹⁷⁾.

In a single-institution, retrospective study of patients who underwent middle meningeal artery (MMA) embolizations for CSDH. Patients with or without antithrombotic initiation within 5 days postembolization were compared. The primary outcome was the rate of recurrence within 60 days. Secondary outcomes included rate of reoperation, reduction in CSDH thickness, and midline shift.

Fifty-seven patients met the inclusion criteria. The median age was 66 years (IQR 58-76) with 21.1% females. Sixty-six embolizations were performed. The median length to follow-up was 20 days (IQR 14-44). Nineteen patients (33.3%) had rapid reinitiation of antithrombotics (5 antiplatelet, 11 anticoagulation, and 3 both). Baseline characteristics between the no antithrombotic (no-AT) and the AT groups were similar. The recurrence rate was higher in the AT group (no-AT vs AT, 9.3 vs 30.4%, P = .03). Mean absolute reduction in CSDH thickness and midline shift was similar between groups. Rate of reoperation did not differ (4.7 vs 8.7%, P = .61).

Rapid reinitiation of AT after MMA embolization for CSDH leads to higher rates of recurrence with similar rates of reoperation. Care must be taken when initiating antithrombotics after treatment of CSDH with MMA embolization ¹⁸⁾.

From 2014 to 2020, the data of 28 patients with chronic subdural hematoma who underwent surgeries with two large burr holes, saline irrigation, and CDS or one small burr hole, no saline irrigation, and external ventricular drainage systems (EVDS) were retrospectively who had preoperative computed tomography (CT), postoperative 1st-3rd day CT, and postoperative 7th-10th day CT were included in the study. Pre- and postoperative subdural liquid collection volumes and postoperative intracranial air volumes were measured using Sectra Medical Workstation. Results were compared between these two groups.

There were no significant differences in the preoperative and 7th-10th day liquid volumes between these two groups (p 0.05). There were significant differences in the postoperative 1st-3rd day air volume between these two groups (p 0.001).

The statistical results showed that surgeries with EVDS are as effective as surgeries with CDS in draining chronic subdural hematomas. They also determined that the intracranial air volume is significantly less in surgeries with EVDS. For this reason, we believe that EVDS can reduce the risk of postoperative infection ¹⁹⁾.

Laeke et al. included patients from Addis Ababa University Hospitals (AAUH) and Haukeland University Hospital (HUH) who had surgery for CSDH (2013-2017). Patients were included prospectively in Ethiopia and retrospectively in Norway.

Results: We enrolled 314 patients from AAUH and 284 patients from HUH, with a median age of 60 and 75 years, respectively. Trauma history was more common in AAUH (72%) than in HUH patients (64.1%). More patients at HUH (45.1%) used anticoagulants/antiplatelets than at AAUH (3.2%). Comorbidities were more frequent in HUH (77.5%) than in AAUH patients (30.3%). Burr hole craniotomy under local anesthesia and postoperative drainage was the standard treatment in both countries. Postoperative CT scanning was more common at HUH (99.3%) than at AAUH (5.2%). Reoperations were more frequent at HUH (10.9%) than at AAUH (6.1%), and in both countries, mostly due to hematoma recurrence. Medical complications were more common at HUH (6.7%) than at AAUH (1.3%). The 1-year mortality rate at HUH was 7% and at AAUH 3.5%. At the end of follow-up (> 3 years), the Glasgow Outcome Scale Extended (GOSE) score was 8 in 82.9% of AAUH and 46.8% of HUH patients.

The surgical treatment was similar at AAUH and HUH. The poorer outcome in Norway could largely be explained by age, comorbidity, medication, and complication rates ²⁰⁾.

Krothapalli et al., performed a retrospective review of patients who underwent middle meningeal artery embolization for chronic subdural hematoma. Transradial access was performed by utilizing a combination of 6F 90cm ENVOY Guiding Catheter Simmons 2 guide catheter and 5F 125cm Sofia (Microvention, Aliso Viejo, CA) intermediate catheter. Outcomes measured are Modified Rankin Score (mRS) at 90 days, inpatient mortality, post-embolization recurrence, fluoroscopy time and radiation exposure. A total of 71 patients underwent 97 MMA embolization overall with 65 (67%) in trans-femoral access group, 11 (11.3%) in trans-radial access without use of Simmons 2 Guide catheter group and 21 (21.6%) in trans-radial access with use of Simmons 2 Guide catheter group. There were no direct access-related complications in either group. One patient had thromboembolic stroke in trans-femoral group. There was no difference in average procedure-related total fluro time or radiation dose among all three groups.

Trans-radial approach using 6F-SIM2 guide catheter coupled with 5F Sofia intermediate catheter is safe and effective. It provides an alternative approach to access distal branches of bilateral anterior circulation in elderly patients with difficult anatomy undergoing MMA embolization ²¹⁾.

A total of 90 patients (71 men and 19 women), aged 41-100 years (mean age, 76.4 ± 11.2 years), were included. CSDH recurred in 17 patients (18.9%). A higher Charlson Comorbidity Index (CCI) correlated with higher scores in the NIHSS. In the univariate analysis, recurrence was associated with a higher CCI (2.39 vs 1.22, p = 0.002), higher NIHSS scores (6.5 vs 4, p = 0.034), and lower prothrombin time (PT) levels (9.9 vs 13.4, p = 0.007). In multivariate analysis, only PT and CCI demonstrated to be independent risk factors for CSDH recurrence after surgical evacuation (p = 0.033 and p = 0.024, respectively). Patients with more comorbidities have a higher risk of developing recurrent CSDH. Charlson Comorbidity Index (CCI) provides a simple way of predicting recurrence in patients with chronic subdural hematoma and should be incorporated into decision-making processes, when counseling patients ²²⁾.

A Institutional based cross-sectional retrospective study was conducted among patients operated for CSDH from January 1, 2012 to December 31, 2015 at Teklehaymanot General Hospital, a private hospital in Addis Ababa, Ethiopia. Descriptive statistics, using SPSS version 20, was used to determine the postoperative outcomes including hospital stay, complications and recurrence rate.

Of the 195 charts reviewed, 70.3% were of males, with M: F ratio of 2.4:1. 68.2% of patients being above the age of 55 years with a mean age at presentation of 57.63. The most common presenting symptom was headache followed by extremity weakness. The diagnosis of CSDH was made with either head CT scan or MRI. Forty one percent of patients had a left side hematoma and 48(24.6%) patients had bilateral CSDH. All patients were operated with a single burr hole evacuation under local anesthesia and postoperative subdural closed system drainage by a single neurosurgeon. The mean hospital stay was 3.68±2.6 days. The postoperative outcome was assessed using the Glasgow Outcome Score, and 95.9% of the patients reported good recovery. Thirteen (6.6%) patients were operated twice for recurrence, and there were four deaths.

Single burr hole trephination for chronic subdural hematoma is an easy, safe and effective technique ²³⁾.

Gazzeri et al. conducted a single-center retrospective analysis on 414 patients surgically treated for CSDH over a period of 6 years. Comparisons were made after dividing the patients into 4 groups based on the surgical technique and type of drainage: Single burr hole with subdural drainage (Group Ia), single burr hole with subgaleal drainage (Group Ib), craniotomy with subdural drainage (Group IIa), and craniotomy with subgaleal drainage (Group IIb). 238 cases underwent a burr hole with irrigation, while 290 cases were treated with craniotomy. Of the analysed patients, subdural drainage was inserted in 382 cases, while subgaleal drain was used only in 146 patients, for a total of 528 procedures.

Re-operation was performed in 9.47 % of cases. The frequency of re-intervention for recurrences appeared to be lower in the Group I a (5.06 %), while the frequency of the re-intervention was higher in the craniotomy with subdural drainage group (Group IIa, 11.6 %). 14 patients (2.65 %) developed acute subdural rebleeding in the immediate postoperative period with 6 of them on antiplatelets/anticoagulants in the preoperative period.

Recurrence rate and functional outcome after surgical drainage of CSDH does not appear to be affected by surgical technique (craniotomy vs burrhole) and drainage location. To our opinion, surgeons may elect procedures on a case-by-case basis ²⁴⁾.

80 patients who had undergone percutaneous TDC for CSDH between January 2017 and December 2018. Patients between 18 and 90 years of age were selected. CSDH showing computed tomography (CT) scan findings of homogeneous hypodensity, homogeneous isodensity, mixed density, and CSDH with hyperdense gravity-dependent fluid level were selected. CT evidence of multiple septations, recurrent CSDH, bilateral CSDH, and acute on CSDH were excluded. The presence of midline shift (MLS) was measured as any deviation of the septum pellucidum from the midline. The mass effect was determined by the effacement of the sulci, Sylvian fissure obscuration, or compression of lateral ventricles. Postoperative decrease in the signs and symptoms were considered as the postoperative clinical improvement. Improvement in the postoperative CT scan was determined by the decrease in the thickness of CSDH and absence of MLS with decrease in the mass effect. The presence of the CSDH with mass effect and MLS was considered as the significant residue in the postoperative CT scan. Statistical Analysis Statistical analysis is done using Epi Info software. Results The mean age range was 67.78 years ± 12.03 standard deviation (SD). There were 49 (61.25%) males and 31 (38.75%) females. Thirty-eight (47.5%) CSDHs were on the right side and 42 (52.5%) on the left side. The locations were in the frontotemporoparietal region in 91.25% patients and in the frontoparietal region in 8.75% patients. The mean duration of symptoms was 4.62 days ± 5.20 SD. History of trauma was present in 58.75% patients. The mean duration of trauma was 45.78 days ± 28.32 SD. The most common symptoms were weakness of the limbs (68.75%), altered sensorium or decreased memory (52.5%), and headache (32.5%). The preoperative Glasgow Coma Scale (GCS) score ranged from 4 to 15 (mean 12.86 ± 2.98 SD). Limb motor weakness was noted in 75% patients. The maximum thickness of the CSDH (in millimeter) in axial CT scan was 8 to 32 (mean 23.22 ± 4.87 SD). All of the 80 patients had MLS. Postoperative GCS ranged from 3 to 15 (mean 14.1 ± 2.78 SD). Postoperative power was improved in 95% of affected limbs. Postoperative power was deteriorated (including patients of complications and death) in 5% patients. Clinical improvement was noted in 93.75% patients. Postoperative CT scan improvement was noted in 95% patients. Two patients (2.5%) had significant residue which required reoperation. Two patients (2.5%) developed extradural hematoma which was operated. Five (6.25%) patients developed complications, among which 4 (5%) patients died. The mean duration of stay in the hospital was 6.82 days ± 4.16 SD. Conclusions CSDH is a disease of elderly population. CSDH is more common in male population. The most common symptom is weakness of the limbs. High clinical and radiological improvement can be achieved with TDC. TDC should be considered as a safe and effective alternative to burr hole craniostomy ²⁵⁾

Certo et al. retrospectively analysed the clinical and radiological data of a minimally invasive, percutaneous draining system (Integra ™) used in fifteen patients (Group A; mean age: 75.7) with CSH, and compare them with those obtained from two retrospective series of patients: the first one (Group B 15 patients, mean age 77.1) treated with standard, single-burr hole technique for subdural drainage under general anaesthesia; the second one (Group C 15 patients, mean age 76.4) treated with standard, single-burr hole technique for subdural drainage under local anaesthesia and mild sedation. All The percutaneous procedures (Group A) were performed under local anaesthesia.

Mean follow-up was 10.9 (range 3-14), 18.2 (range 10-29) and 15.2 (range 8-28) months in Group A, B and C respectively. Three of 15 and in Group B experienced a worsening of pre-existing neurodegenerative disorders after general anaesthesia. One patient in group C suffering from Parkinson's disease experienced a worsening of gait disturbances. Post-operative CT scans were performed at 48 h and 21 days after the operation. An early post-operative CT-scan, obtained immediately after surgical procedure, was performed in all Group A patients. No differences in CSH evacuation were observed comparing the three groups. Two recurrent hematomas, one in group A and one in group B, required revision. Post-operative hospitalization was similar (5.1 vs 5.7 vs 5.6 days, respectively, in group A, B and C) but analgesics use was lower in Group A.

Pre-operative evaluation of radiological features of CSDHs is crucial in determining the right indication for a minimally invasive drainage. Minimally invasive treatments of CSH may reduce the use of anaesthetic drugs and worsening of pre-existing neurodegenerative disorders ²⁶⁾.

Tommiska et al., conducted a retrospective observational study including consecutive patients undergoing burr hole trephinations for CSDHs. They compared outcomes between a six-month time period when the SD placement was arbitrary (July to December 2015) and a time period when subdural drain (SD) placement for 48 h was routine (July to December 2017). The primary outcome of interest was recurrences requiring reoperation within six months. Furthermore, patient outcome, infections and other complications were assessed.

A total of 161 patients were included, of which 71 (44%) were in the SD group and 90 (56%) in the non-drain group. There were no differences in age, comorbidities, history of trauma or use of antithrombotic medication between the groups (p>0.05). Recurrences within six months occurred in 18% of patients in the non-drain group compared to 6% in the SD group (p=0.028; OR 0.28; 95% CI 0.09-0.87). There were no differences in neurological outcome (p=0.72), mortality rate (p=0.55), infection rate (p=0.96) or other complications (p=0.20).

The change in practice from no drain to SD after burr-hole craniostomies for CSDHs effectively reduced the six-month recurrence rate without any effect on patient outcome, infections or other complications ²⁷⁾.

A total of 763 patients with surgically evacuated unilateral CSDH were included for analysis. The recurrence rate was 14% while 12% of patients died during follow-up (1 year). In a association model, hematoma size, drain type, drainage time, presence of complications, and Glasgow Coma Score were significantly associated to recurrence. Subdural drain was associated with a lower recurrence risk than subgaleal drain. The preoperative model included hematoma size, hematoma density, and history of hypertension. The postoperative model included further drain type, drainage time, and surgical complications.

The nomograms allow easy assessment of the recurrence risk for the individual patient, providing a better possibility for individual adjustment of treatment and follow-up. The predictive performance indicates that significant unaccounted or unknown factors still remain. The association test found passive subdural drain superior to passive subgaleal drain in minimizing the risk of CSDH recurrence ²⁸⁾.

A retrospective analysis of 201 cases of CSDH diagnosed and treated at Beijing Shijitan Hospital (CMU) from January 2006 to December 2017 was conducted. From January 2006 to December 2010, 126 cases of CSDH were treated with skull drilling and drainage (non-endoscopic group). From January 2011 to December 2017, 75 cases of CSDH were treated with soft neuroendoscopy (endoscopic group). The operation time of the non-endoscopic and endoscopic groups, the hematoma clearance rate on the first day after surgery, the time of the drainage tube, the length of hospital length of stay, the incidence of complications, mortality and recurrence rate were compared.

There were no deaths in both groups. The average operation time of the non-endoscopic group was 43 min, compared with the average operation time of the endoscopy group of 50 min, there was no significant difference (P>0.05). The average hematoma clearance rate on the first day after surgery in the endoscopy group (98.2%) was significantly higher than that in non-endoscopic group (87.3%) (P<0.01). The average time of drainage tube in the endoscopy group (23 h) was significantly shorter than that in the non-endoscopic group (50 h) (P<0.01). On the first postoperative day, the proportion of patients with mRS≤3 in the endoscopic group was significantly higher than that in the non-endoscopic group (P<0.01). At the time of discharge, the proportion of patients with mRS≤3 in the endoscopy group was also significantly higher than that in the non-endoscopic group, P<0.05. There was no significant difference in the average hospital stay between endoscopy group (7 d) and non-endoscopic group (8 d) (P>0.05). The postoperative complication rate in the endoscopy group was significantly lower than that in the non-endoscopic group (P<0.01). During 0.5-8 years of follow-up, the recurrence rate of CSDH in the endoscopic group (5.33%) was significantly lower than that in the non-endoscopic group (15.07%) (P<0.01).

The application of visualization features of soft neuroendoscopy in the treatment of CSDH can significantly improve hematoma clearance, shorten the time of drainage tube, reduce postoperative complications and recurrence rate, and improve surgical outcomes ²⁹⁾.

Glancz et al. from the Department of Neurosurgery, Queen's Medical Centre, Derby Road, Nottingham, Edinburgh, Royal Victoria Infirmary, Newcastle, and Addenbrooke's Hospital, Cambridge, United Kingdom, performed a subgroup analysis of a previously reported multicenter, prospective cohort study of CSDH patients performed between May 2013 and January 2014. Data were analyzed relating drain location (subdural or subgaleal), position (through a frontal or parietal burr hole), and duration of insertion, to outcomes in patients aged >16 yr undergoing burr-hole drainage of primary CSDH. Primary outcomes comprised modified Rankin scale (mRS) at discharge and symptomatic recurrence requiring redrainage within 60 d.

A total of 577 patients were analyzed. The recurrence rate of 6.7% (12/160) in the frontal subdural drain group was comparable to 8.8% (30/343) in the parietal subdural drain group. Only 44/577 (7.6%) patients underwent subgaleal drain insertion. Recurrence rates were comparable between subdural (7.7%; 41/533) and subgaleal (9.1%; 4/44) groups (P = .95). They found no significant differences in discharge mRS between these groups. Recurrence rates were comparable between patients with postoperative drainage for 1 or 2 d, 6.4% and 8.4%, respectively (P = .44). There was no significant difference in mRS scores between these 2 groups (P = .56).

Drain insertion after CSDH drainage is important, but position (subgaleal or subdural) and duration did not appear to influence recurrence rate or clinical outcomes. Similarly, drain location did not influence recurrence rate nor outcomes where both parietal and frontal burr holes were made. Further prospective cohort studies or randomized controlled trials could provide further clarification ³⁰⁾.

A burr hole opening with closed system drainage was performed on 124 chronic subdural hematomas (CSDHs) in 102 patients of the Department of Neurosurgery, Teikyo University Hospital Mizonokuchi, Futago, Takatsu-ku, Kawasaki, Kanagawa, Department of Neurosurgery, Teikyo University Medical School, Kaga, Iabashi-ku, Tokyo Japan, Department of Neurosurgery, Loma Linda University Medical Center, California USA. Hematoma thickness and midline shift were measured by computed tomography scan and hematoma pressure was measured with glass manometers in surgery. In accordance with Laplace's law, tension on the motor cortex was calculated as (half the hematoma thickness × hematoma pressure)/2. Student's t-test and Pearson value (r: relationship index) were applied in statistical analysis of findings.

Motor weakness was identified in 76.5% of our cases, and severity of hemiparesis showed no correlation with age. Tension was strongly related to hemiparesis (r = -0.747, p<0.01), whereas hematoma thickness (r = -0.458, p<0.01) and pressure (r = -0.596, p<0.01) were moderately correlated with hemiparesis. Fourteen patients (13.7%) complained of headache and mean age of these patients was much younger than those without headache (p<0.01). Stronger midline-shift (p<0.01) and greater ratio of midline-sift to hematoma thickness (p<0.01) were statistically correlated with headache. Recurrence of CSDH was recognized in eight patients (7.8%). Seven of them had no further recurrence after a second surgery and one patient required a third surgery. Stronger midline-shift (p<0.05) and greater ratio of midline-shift to hematoma thickness (p<0.05) were statistically associated with recurrence, although hematoma thickness, pressure, and tension were not correlated with recurrence.

Tension is the most influencing factor to development of hemiparesis in patients with CSDH, showing that thick hematoma causes mild motor weakness if the hematoma pressure is low. This study also elucidates the mechanism for quick recovery from hemiparesis after burr-hole surgery in that tension on the motor cortex is decreased immediately by drainage although the subdural space remains wide. However, high tension to the brain cortex was not correlated with either headache or recurrence of CSDH ³¹⁾.

A retrospective two-centre study including 151 surgically treated patients. A univariate (Fisher exact test) and multivariate (logistic regression) analysis of possible risk factors influencing outcome was performed. Outcome was expressed as: 6-month clinical outcome, 6-month mortality, complications and length of hospital stay.

Univariate analysis showed an association between Charlson Comorbidity Index (CCI) and 6-month clinical outcome (p = 0,048), complications (p = 0,034) and 6-month mortality (p = 0,007). Antithrombotic drugs were associated with longer hospital stay (p < 0,001). Logistic regression analysis showed an association between CCI and complications (p = 0,016, HR = 3,18) and 6-month mortality (p = 0,034, HR = 11,71), and between antithrombotic drugs and longer hospital stay (p = 0,002, HR = 3,07).

Age alone is not a predictor of bad outcome for patients aged 80 years and older surgically treated for CSDH. Charlson Comorbidity Index (CCI) may prove a valuable outcome predicting tool in these patients, and a longer hospital stay may be anticipated for patients under antithrombotic agents ³²⁾.

Matsumoto et al. analyzed 492 consecutive patients with CSDH between January 2010 and October 2015. First, we analyzed the clinical factors and compared them between patients with or without brain herniation signs on admission. Second, we compared clinical factors between patients with or without completion of brain herniation after operation among patients who had brain herniation signs on arrival. Eleven (2.2%) patients showed brain herniation signs on arrival, and six patients (1.2%) progressed to complete brain herniation. Patients with brain herniation signs on arrival were significantly older (P = 0.03) and more frequently hospitalized with a concomitant illness (P < 0.0001). Niveau formation (P = 0.0005) and acute-on CSDH (P = 0.0001) on computed tomography were also more frequently seen in patients with brain herniation signs. Multivariate logistic regression analysis showed that age older than 75 years (OR 2.16, P < 0.0001), niveau formation (OR 3.09, P < 0.0001), acute-on CSDH (OR 14, P < 0.0001), and admitted to another hospital (OR 52.6, P < 0.0001) were independent risk factors for having had brain herniation signs on arrival. On the other hand, having a history of head injury (P = 0.02) and disappearance of the ambient cistern (P = 0.0009) were significantly associated with completion of brain herniation. The prognosis was generally poor if the patient had presented with brain herniation signs on admission. Our results demonstrate that the diagnosis is often made late, despite hospitalization for a concomitant illness. When the elderly show mild disturbance of consciousness, physicians except neurosurgeons need to consider the possibility of CSDH regardless of a recent history of head injury ³³⁾.

15 patients who underwent operation for CSDHs between June 2012 and June 2014 at Sir Run Run Shaw Hospital of Zhejiang University were included in this retrospective cohort study. The clinical and imaging data of these patients with CSDHs due to spinal CSF leak were retrospectively studied. Fifteen patients, with a mean age of 53.8 ± 8.3 years, underwent operations for CSDH. Hematomas were unilateral in 4 patients and bilateral in 11 patients. Among these patients, eight patients had recurrence of hematomas after operation due to neglect of spinal CSF leak. All patients had fully recovery ³⁴⁾.

All patients with CSDH treated by BHD between January 2012 and December 2014 were included in this study. All patients were classified by symptom, clinical grade, time, location, hematoma density, midline shift, and other characteristics. Pre- and postoperative CT evaluation was performed at 0, 3, and 6 months. Clinical grades were classified with the Markwalder grading score.

Surgical and clinical outcomes were evaluated with the brain expansion rate and modified Rankin Scale (mRS). Brain expansion rate was calculated as the ratio between post- and pre-operative hematoma thickness. Recurrence was defined as the occurrence of symptoms and hematoma on CT within 6 months.

This study included 130 patients over 2 years. Among the variable parameters, young age (<75), iso-density of hematoma on CT, and short duration from symptom to surgery were correlated with good brain expansion. Patients with good brain expansion had fewer recurrences. In terms of mRS, young age, iso-density, and good clinical grade were correlated with good functional outcomes.

Clinicians should be more aware of general conditions and medical problems, especially in elderly patients. Membranectomy should be considered in patients with a long duration of symptoms or hypodense hematomas to promote good brain expansion and good mRS scores ³⁵⁾.

242 cases of chronic SDH. The cSDHs were classified into four groups; hypodensity, homogeneous isodensity, layered type, and mixed type on the basis of CT scans.

The density of cSDH was isodense in 115 patients, hypodense in 31 patients, mixed in 79 cases, and layered in 17 cases. The cSDH was on the left side in 115 patients, on the right side in 70 patients, and bilateral in 40 patients. The history of trauma was identifiable in 122 patients. The etiology could be identified in 67.7% of the hypodense hematomas, while it was obscure in 59.5% of the mixed hematomas.

Mixed density of cSDH results from multiple episodes of trauma, usually in the aged. It is hard to remember all the trivial traumas for the patients with the mixed density cSDHs. Although there were membranes within the mixed density hematomas, burr-holes were usually enough to drain the hematomas ³⁶⁾.

Eighty-seven patients with CSDH underwent surgery at a institution from January 2004 to December 2008. The patients were classified into three groups according to the operative procedure; group I, one burr-hole craniostomy with closed system drainage with or without irrigation (n = 25), group II, two burr-hole craniostomy with closed system drainage with irrigation (n = 32), and group III, small craniotomy with irrigation and closed-system drainage (n = 30).

Age distribution, male and female ratio, Markwalder's grade on admission and at the time of discharge, size of hematoma before and after surgery, duration of operation, Hounsfield unit of hematoma before and after surgery, duration of hospital treatment, complication rate, and revision rate were categories that we compared between groups. Duration of operation and hospitalization were only two categories which were different. But, when comparing burr hole craniostomy group (group I and group II) with small craniotomy group (group III), duration of post-operative hospital treatment, complication and recurrence rate were statistically lower in small craniotomy group, even though operation time was longer.

Such results indicate that small craniotomy with irrigation and closed-system drainage can be considered as one of the treatment options in patients with CSDH ³⁷⁾.

A total of 42 patients treated with the burr hole craniotomy without irrigation with drainage were compared to 40 patients with irrigation and drainage. In both groups, univariate and multivariate analysis revealed that good clinical outcome was associated with preoperative Markwalder grade and the presence of postoperative hematoma recurrence. There was no difference in good outcome between the 2 operative methods.

There was no significant difference between these 2 operative techniques in relation to outcomes whether good or bad. The recurrence rate was 12.2%. When either technique is done properly, no difference to the outcome is seen. Neurosurgeons or general surgeons in Southeast Asia may choose not to irrigate the chronic subdural space, although drainage placement is necessary afterwards ³⁸⁾.

Gazzeri et al. present a technique for the management of chronic subdural haematoma which is a variation of a closed drainage system. After evacuation of the haematoma through a single burr hole, they inserted a Jackson Pratt drain into the subgaleal space, with suction facing the burr hole, allowing for continuous drainage of the remaining haematoma.

They used the method for over 4 years to treat 224 patients. Seventeen patients (7.6%) needed a second operation for a recurrence of the haematoma no patient required a third operation. Postoperative complications developed in 3 patients. Two patients died while in the hospital, a mortality rate of 0.9%.

The use of suction assisted evacuation, is followed by results that compare satisfactorily to reports of previous methods, with a low rate of recurrence and complications. It is relatively less invasive and can be used in high risk patients ³⁹⁾.