Angiographic classification of chronic subdural hematoma.

Background and purpose:

Chronic subdural hematoma (cSDH) is a challenging pathology with high recurrence rate after surgical treatment and may seriously affect the patient’s quality of life. Membrane formation with angiogenesis plays an important role in the evolution of the disease, providing a promising target for endovascular therapy. Our goal is to categorize angiographic patterns of chronic subdural hematoma for standardized reporting purposes.

In our retrospective analysis of prospective data collection, we analyzed angiographic properties of all high recurrence risk patients with cSDH, who were treated by embolization in our hospital between February 2019 and June 2020. Altogether 17 patients were included in the analysis. 

Based on superselective angiography of the middle meningeal artery (MMA) in the two standard, AP and lateral views, three distinct categories of dural supply were defined: normal vascular pattern (Grade I), cottonwool appearance without enlargement of the MMA branches (Grad II) and strong cottonwool like staining with dilatative remodelling of the MMA branches (Grade III).

The proposed grading system of the angiographic appearance of cSDH, representing the pathophysiological evolution of the disease should be correlated to therapeutic success rates and could be applied in future clinical studies.

Modified Computed Tomography Classification for Chronic Subdural Hematoma Features Good Interrater Agreement: A Single-Center Retrospective Cohort Study.

OBJECTIVE: The present study aimed to establish whether our modified Nakaguchi computed tomography (CT) classification improves the interrater agreement of chronic subdural hematoma (CSDH) classification and prediction of CSDH recurrence relative to 2 other CT classifications. METHODS: This retrospective study considered 277 consecutive patients with CSDH and 307 hematomas treated with burr-hole surgery between January 2009 and December 2018. Two neurosurgeons blinded to patients' clinical data classified the CT scans of patients with CSDH into 4 or 5 types according to the Nomura classification (high, iso, low, mixed, and layering), Nakaguchi classification (homogenous, laminar, separated, and trabecular), and our modified Nakaguchi classification (homogenous, gradation, laminar, separated, and trabecular). The κ statistic was used to evaluate the interrater agreement of the 3 CT classifications. Univariable and multivariable logistic regression analyses were used to calculate odds ratios for CSDH recurrence. RESULTS: κ values of the modified, Nakaguchi, and Nomura classification were 0.78, 0.63, and 0.70, respectively. During the 3 months follow-up, the recurrence rate for CSDH was 11.4% (35/307 hematomas). Of the types defined by the modified classification, the gradation type was associated with the highest recurrence (mean recurrence rate, 15.9% ± 0.3%). Multivariable logistic regression analyses showed that a gradation-type hematoma, as defined with the modified classification, was an independent risk factor associated with recurrence (odds ratio, 2.36; 95% confidence interval, 1.11-4.98; P = 0.025). CONCLUSIONS: The modified classification was useful for preoperative CT classification of CSDH and the prediction of recurrence, with high agreement between raters.

Chronic Subdural Hematoma: Toward a New Management Paradigm for an Increasingly Complex Population.

Chronic subdural hematoma (cSDH) is a frequent yet poorly studied entity. Patients with cSDH are increasingly using antithrombotic medication, are now older, and present with a variety of clinical symptoms, including incidental discoveries. Despite this increasing complexity, management has remained roughly unchanged since the late 1990s. We review here the state of cSDH research under way at Université de Sherbrooke and around the world with a focus on studies addressing specific gaps in the current evidence base. We show that evidence is lacking at many decision points in the typical cSDH patient treatment algorithm. No definition of cSDH is universally accepted, and a formal definition project, along with suggested common data elements to be reported in future trials (CODE-CSDH: formal cSDH definition project) is ongoing. An amendment to International Statistical Classification of Diseases and Related Health Problems (ICD-11) has also been proposed to improve classification and registry research. Within the cSDH clinical assessment, evidence for the occurrence of nonepileptic, stereotypical, and intermittent symptoms (NESIS) is emerging. The GENESIS study (Generation Evidence on the etiology and management of NESIS) will test etiological and therapeutic hypotheses for this patient subpopulation. For patients at high risk of recurrence, the TRACS (TXA for cSDH) and EMMACS studies (Embolization of the Middle Meningeal Artery in Chronic Subdural Hematoma study) are, respectively, assessing the use of tranexamic acid and meningeal artery embolization. The overarching vision is that patients with cSDH might be stratified for operative versus conservative treatment based on the need for mass effect removal, then be offered adjuvant therapies based on their risk of recurrence and thrombotic complications. We believe that such tailoring of therapy to each individual should help improve outcomes.

Histopathological features of the outer membrane of chronic subdural hematoma and correlation with clinical and radiological features.

We compared the histopathological features of the outer membrane of a chronic subdural hematoma (CSH) with its clinico-radiological presentation in patients. One hundred and fifty-six patients undergoing surgery for CSH were prospectively included in this study. Histopathological specimens of the outer neomembrane obtained intraoperatively were studied. Histological features were classified into four types and analyzed in relation to the Glasgow Coma Scale (GCS) score at presentation and radiological features. On histopathological examination, there were no cases of type I, 42.3% cases of type II and 34.6% cases of type III and 23.1% cases of types IV CSH neomembranes. Patients presenting with a GCS <13 exclusively had type II neomembranes. Increased radiodensity and thickness of the hematoma correlated with type IV neomembranes. This study may serve as an incentive to investigate the histopathology of CSH membranes in predicting outcomes and the recurrence of subdural hemorrhage after drainage surgery.

Measurement of inflammatory cytokines and thrombomodulin in chronic subdural hematoma.

Inflammation and the coagulation system may influence the genesis of chronic subdural hematoma (CSDH). The appearance of CSDH on computed tomography (CT) varies with the stage of the hematoma. This study investigated the pathogenesis and the recurrence of CSDH by comparing cytokine levels with the CT features of CSDH in 26 patients with 34 CSDHs who underwent single burr-hole surgery at our hospital between October 2004 and November 2006. The hematoma components removed during the procedure were examined, and the hematoma serum levels of cytokines measured such as thrombomodulin (TM), interleukin-6 (IL-6), tumor necrosis factor-α (TNFα), and interleukin-10 (IL-10). Using CT, mixed density hematomas were distinguished from other homogeneous hematomas, and found that the TM level was significantly higher in mixed density hematomas than in homogeneous hematomas (p = 0.043). Mixed density hematomas were classified into three subtypes (laminar, separated, and trabecular hematomas). The TM level was significantly higher in laminar and separated hematomas than in other hematomas (p = 0.01). The levels of IL-6, TNFα, and IL-10 were extremely high, but showed no significant differences in relation to the CT features. Mixed density hematomas had high recurrence rate, as reported previously, and TM level was high in mixed density hematomas such as laminar and separated mixed density hematomas. The present findings suggest that the types of CSDH associated with high TM levels tend to have higher recurrence rate.

Randomized comparative study of burr-hole craniostomy versus twist drill craniostomy; surgical management of unilateral hemispheric chronic subdural hematomas.

OBJECTIVE: Although there is a tendency to minimize the surgical procedures for chronic subdural hematomas, there is no agreement on the optimal treatment. In the literature there is only one published result of a randomized study comparing twist drill craniostomy with burr-hole craniostomy. We aimed to compare twist drill craniostomy with burr-hole craniostomy for the treatment of unilateral hemispheric chronic subdural hematomas in adults. MATERIAL AND METHODS: The study was planned as a prospective, randomized, controlled investigation. Between November 2002 and April 2006, 70 patients (54 male and 16 female) with unilateral hemispheric chronic subdural hematomas were operated. 32 patients underwent burr-hole craniostomy and 38 patients were treated by twist drill craniostomy. After discharge, the patients were followed up at 1, 3 and 6 months after operation. Mortality, morbidity, surgical complications requiring reoperation, duration of hospitalization, recurrence, total number of reoperations, and cure rates were compared. RESULTS: Two patients died and one patient developed 6th nerve paresis in the inpatient period. There were three recurrences (two in the burr-hole craniostomy group, one in the twist drill craniostomy group) and in one patient from the burr-hole craniostomy group a chronic subdural hematoma developed on the contralateral side postoperatively. There was no significant difference clinically and radiologically between the two groups at any time period. CONCLUSION: Both surgical methods seem effective for the treatment of unilateral chronic subdural hematomas.

[Relationship between classification of CSDH according to the Internal architecture and hematoma contents].

BACKGROUND: Based on the finding of temporal changes in the internal architecture on CT scans, we classified CSDH into 4 types: the homogeneous type, the laminar type, the separated type, and the trabecular type. The purpose of this study was to statistically analyze the relationship between the type of CSDH and the hematoma contents. METHODS: This study assessed 45 consecutive CSDH patients. All of them were assigned to our 4 types of CT classification of CSDH, and the counts of blood cells including WBC, RBC, Hb, Ht, and platelets, as well as FDP and fibrinogen levels in the hematoma and peripheral venous blood were examined. RESULTS: The mean RBC count was 345.3 (SD = 177.9) in all the subjects versus 426.4 (SD = 165.6) in Hm, 408.3 (SD = 79.2) in Lm, 357.2 (SD = 298.7) in Sp, and 200.0 (SD = 129.2) in Tr. The mean Hb concentration was 10.2 (SD = 5.2) in all the subjects versus 12.9 (SD = 5.3) in Hm, 12.3 (SD = 2.7) in Lm, 9.2 (SD = 6.5) in Sp, and 5.9 (SD = 4.2) in Tr. The eosinophil and lymphocyte counts were high in all the types (15.0% and 48.4% on average). The FDP concentration was high in all patients (500-5,000). Fibrinogen levels were less than 10 in all hematoma types. CRP was an average of 3.1 (SD = 4.9) in all the subjects versus 7.5 (SD = 9.8) in Hm, 2.5 (SD = 1.6) in Lm, 3.0 (SD = 2.9) in Sp, and 1.1 (SD = 1.6) in Tb. CONCLUSION: There were relationships between the type of CSDH and the RBC, Hb, Ht, and CRP values.

[Relationship between the natural history of chronic subdural hematoma and enhancement of the inner membrane on post-contrast CT scan].

The purpose of this study was to determine the features and natural history of the inner membrane in CSDH (chronic subdural hemotoma) patients using pre- and post-contrast CT scans. Twenty-four patients with CSDH (28 hematomas) who underwent pre- and post-contrast CT scanning prior to surgery were studied. CSDH was classified according to the internal architecture as the homogeneous (HM) type, the laminar (LM) type, the separated (SP) type, and the trabecular (TR) type. For each type, the enhancement of the inner membrane, the outer membrane, and trabeculae was evaluated. Enhancement of the inner membrane develops as the stage of CSDH progresses. Although the inner membrane was not enhanced in the HM type, it was enhanced in almost all of the patients with the other types (p < 0.0001). In 13% of patients with the LM type, 29% with the SP type, and 40% with the TR type, the inner membrane was moderately or markedly enhanced. The outer membrane was not thickened in any patient. In 88% of the patients who had contralateral hemiparesis on admission and 42% of those who did not have hemiparesis, the inner membrane was clearly enhanced (p = 0.0166). This indicated that blood flow to the inner membrane from the pia matter induced hypoperfusion of the brain parenchyma beneath the hematoma in addition to the effect of direct compression. Contrast CT scanning may be useful for diagnosing the extent of enlargement of the inner membrane, predicting the risk of local brain damage, and evaluating the stage in the natural history of CSDH.

Chronic subdural hemorrhage into a giant arachnoidal cyst (Galassi classification type III).

The authors present CT and MRI of a patient with an extremely large arachnoidal cyst (Galassi classification type III). The cyst extended from the base of the skull, posterior to the brain stem, on the base of the temporal lobe over the complete convexity of the left hemisphere. The cyst consisted of multiple compartments with intracystic septa and was accompanied by a chronic subdural hemorrhage in the compartments. After contrast agent application, the typical characteristics of chronic subdural membranes were found. Besides bony deformities, a thinning of the inner table was found. The patient underwent craniotomy for evacuation of the hemorrhage and fenestration of the septa while he was free of symptoms. This is a remarkable case proving that chronic local intracranial pressure does not inevitably lead to neurologic symptoms or intellectual disabilities.

Relation between brain displacement and local cerebral blood flow in patients with chronic subdural haematoma.

OBJECTIVES: To evaluate the relation between brain displacement, clinical signs and symptoms, and local cerebral blood flow (lCBF) in patients with chronic subdural haematoma (CSDH). METHODS: Forty five patients (age range 58-87 years, mean 71.9 (SD 8.4)) with unilateral CSDH were studied. Patients were categorised into three groups: I, headache (n=16); II, paresis (n=14); and III, mental change (n=15). T1 weighted MR images were obtained in all patients preoperatively. Quantitative values of maximum haematoma thickness, midline shift, and brain rotation angle were measured on axial and coronal MR images. In 21 patients, lCBF was measured by Xe enhanced CT. Values for lCBF were obtained in selected regions of interest in the frontal cortex, thalamus, and hemisphere on both the haematoma and contralateral sides. RESULTS: The lCBF reduction in the ipsilateral frontal cortex showed the best linear correlation with haematoma thickness (r=0.57), whereas the reduction in the ipsilateral thalamus had the most significant correlation with pineal shift (r=0.65) and third ventricle incline (r=0.67). In patients with paresis, lCBF decreased significantly on the ipsilateral side of both the frontal cortex and thalamus (p<0.05), whereas patients with mental change showed a significant reduction of lCBF on both sides of the thalamus (p<0.01) and in the ipsilateral frontal cortex (p<0.01). CONCLUSIONS: The lCBF reduction and clinical symptoms correlated well with local brain displacement in patients with CSDH. The lCBF in the central cerebral area including the thalamus was reduced in patients with clinical signs. The mental changes found were thought to derive from mild impairment of consciousness due to upper brain stem displacement.