Ultrastructure of collagen fibers in the outer membrane of recurrent chronic subdural hematoma

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.

Analysis of Endoscopic Findings in the Chronic Subdural Hematoma Cavity: Bleeding Factors in Chronic Subdural Hematoma Natural History and as Predictors of Recurrence

OBJECTIVE

Possible factors associated with bleeding from endoscopy-detected chronic subdural hematomas (CSDHs) have rarely been analyzed. We therefore evaluated intraoperative endoscopic findings to elucidate the clinical course and assess predictors of CSDH recurrence.

METHODS

Altogether, 540 CSDHs were reviewed in this retrospective study. Six possible signs of bleeding were detected in the cavity: spotty bleeding on the outer membrane, hematoma clots, cerebral parenchymal suspension, stretched cortical vessels, intraluminal trabecular structures, and septa separating the cavity. We evaluated the association of each with the radiologic findings, endoscopic features, and interval from trauma to surgery and then assessed the correlation between each endoscopic feature and CSDH recurrence.

RESULTS

Spotty bleeding, cerebral parenchymal suspension, and stretched cortical vessels occurred during every period. Hematoma clots exhibited a 2-peak pattern with significant resurgence during the chronic phase. Trabecular structures significantly increased 61 days after the trauma, reaching 71.2% of patients on day 91. Septa were found in the cavity in only 12.5% during the initial 30 days but subsequently increased significantly to 37.3%. At 2 months, an exacerbation stage was inferred. The multivariable analysis revealed that trabecular structures and residual septa were significant independent risk factors for recurrence. We opened most septa intraoperatively. Their recurrence rate was 7.5%, which is lower than has been previously reported.

CONCLUSIONS

Evaluation of the changes in the endoscopic findings and their association with recurrence was useful for clarifying the mechanism of CSDH enlargement, the risk of recurrence, and the potential for endoscopic surgery.

Embolization for Refractory Subacute Subdural Hematoma in a Child with Severe Hemophilia Type A

Hemophilia is an X-linked hemorrhagic disease due to coagulation factor VIII or IX deficiency with approximately 5-10% incidence of central nervous system bleeding. We present an intriguing case of a refractory subacute subdural hematoma (SDH) controlled with endovascular embolization in a hemophilic patient. A 5-year-old severe hemophilic A boy presented with a life threatening left parietal subcortical hemorrhage, for which he underwent craniotomy and evacuation of the hematoma. Recurrent hemorrhage necessitated a repeat craniotomy. This was followed by three episodes of SDH development at the craniotomy site that were treated surgically, and finally controlled with embolization in the subacute period. This case presents a novel option for treating a refractory SDH in patients with coagulation disorders.

Chronic subdural hematomas--causes of morbidity and mortality

OBJECTIVE

Chronic subdural hematoma is a very common condition seen usually in the later stages of life. Treatment, although apparently simple, is associated with some morbidity and mortality with a potential for recurrence. This is especially important as the average life span of humanity increases all over the world.

METHODS

A retrospective analysis of 647 cases of chronic subdural hematomas treated in NIMHANS was done. The aim of this study was to determine the factors responsible for the morbidity, mortality, and recurrence in patients with chronic subdural hematomas.

RESULTS

The patients were mostly men in the sixth and seventh decade of life and presented with headache, cognitive decline, or focal deficits. CT scan was done in all cases. 94% of the patients underwent evacuation of the hematoma. There was a mortality rate of 5%, and there was a recurrence of 21%. Statistical analysis for factors both for mortality and morbidity were done.

CONCLUSIONS

It was seen that statistically significant factors determining mortality were age, GCS at presentation, and associated illnesses like cardiac and renal failure. The statistically significant factors for recurrence are the presence of a thick subdural membrane visualized during surgery and brain, remaining at a depth at the end of evacuation of hematoma. Use of a subdural drain significantly reduced recurrences. The chronicity of the hematoma was not a factor determining mortality or morbidity. Drains were seen to significantly reduce recurrence in younger patients with better GCS and when the subdural membrane is seen at surgery and the brain remains at a depth at the end of hematoma evacuation.

Clinical factors of recurrent chronic subdural hematoma

The clinical, radiological, and operative factors of recurrent chronic subdural hematoma (CSDH) were retrospectively analyzed in 116 patients with CSDH in 134 hemispheres, treated by one burr hole surgery. The correlation of recurrence was evaluated with personal and clinical factors such as age, sex, history of head injury, and interval from onset of initial symptoms to hospitalization; laboratory findings such as bleeding tendency and liver function; computed tomography (CT) findings such as hematoma density and brain atrophy; and operative findings such as additional procedures and postoperative residual air. The recurrence group (RG) included 10 hemispheres (7.5%) in 10 patients (8.6%). The interval from onset of symptoms to hospitalization was significantly shorter in the RG than in the nonrecurrence group (NRG). Headache was more frequently seen in the RG than in the NRG. Density of hematoma on CT was classified into five types: Low, iso, and high density, niveau, and mixed, and the incidence of recurrence was 0%, 2.3%, 17.2%, 12.5%, and 6.5%, respectively. Larger amounts of residual air in the postoperative hematoma cavity were associated with recurrence of CSDH. CSDH that progresses rapidly in the acute stage and appears as high density on preoperative CT is associated with a high incidence of recurrence. Intraoperative air invasion to the hematoma cavity should be avoided to prevent recurrence.