Management and outcomes of isolated interhemispheric subdural hematomas associated with falx syndrome

The Extension of Traumatic Subdural Hematoma into the Interhemispheric Fissure Is Associated with Coagulation Disorders: A Retrospective Study

BACKGROUND

 This study investigates the correlation of the radiologic sign of interhemispheric subdural hematoma (iSDH) in different injury patterns with clinical coagulation disorders. It is hypothesized that the presence of iSDHs is correlated with clinical coagulation disorders in patients with traumatic brain injuries and subdural hematoma (SDH).

METHODS

 Between January 1, 2020 and June 30, 2022, 154 patients with SDH were identified. Coagulation disorders were assessed using chart review and patients were divided into four groups: SDH without iSDH without further injuries (SDH), SDH with iSDH without further injuries (SDH + iSDH), SDH without iSDH with further brain injuries (Combi), SDH with iSDH with further injuries (Combi + iSDH). These four groups were formed under the assumption that isolated SDHs result from a highly specific trauma mechanism (rupture of bridging veins) in predisposed elderly patients, while combined brain injuries with SDH result from a severe global traumatic brain injury combining different pathophysiologic mechanisms often in younger patients. The groups were analyzed for patient demographics, clinical presentation, and association with coagulation disorders. The significance level was set at p < 0.005.

RESULTS

 The presence of an iSDH was associated with a higher likelihood of concomitant coagulation disorder or anticoagulants in cases of isolated subdural hemorrhage (56.8% of the population in SDH vs. 94.7% in SDH + iSDH, p < 0.005). This effect was not significant in the cases with combined traumatic brain injuries (33.3% in Combi vs. 53.6% in Combi + iSDH, p > 0.005).

CONCLUSION

 Our data indicate a high positive predictive value (PPV = 94.7%) for coagulation disorders in traumatic SDH patients with iSDH without any further focal and diffuse brain injuries. We consider this a relevant finding since it hints at the presence of coagulation disorders and might be used in early hemostaseologic assessment and emergency management.

Simulating Cerebral Edema and Ischemia After Traumatic Acute Subdural Hematoma Using Triphasic Swelling Biomechanics

Poor outcome following traumatic acute subdural hematoma (ASDH) is associated with the severity of the primary injury and secondary injury including cerebral edema and ischemia. However, the underlying secondary injury mechanism contributing to elevated intracranial pressure (ICP) and high mortality rate remains unclear. Cerebral edema occurs in response to the exposure of the intracellular fixed charge density (FCD) after cell death, causing ICP to increase. The increased ICP from swollen tissue compresses blood vessels in adjacent tissue, restricting blood flow and leading to ischemic damage. We hypothesize that the mass occupying effect of ASDH exacerbates the ischemic injury, leading to ICP elevation, which is an indicator of high mortality rate in the clinic. Using FEBio (febio.org) and triphasic swelling biomechanics, this study modeled clinically relevant ASDHs and simulated post-traumatic brain swelling and ischemia to predict ICP. Results showed that common convexity ASDH significantly increased ICP by exacerbating ischemic injury, and surgical removal of the convexity ASDH may control ICP by preventing ischemia progression. However, in cases where the primary injury is very severe, surgical intervention alone may not effectively decrease ICP, as the contribution of the hematoma to the elevated ICP is insignificant. In addition, interhemispheric ASDH, located between the cerebral hemispheres, does not significantly exacerbate ischemia, supporting the conservative surgical management generally recommended for interhemispheric ASDH. The joint effect of the mass occupying effect of the blood clot and resulting ischemia contributes to elevated ICP which may increase mortality. Our novel approach may improve the fidelity of predicting patient outcome after motor vehicle crashes and traumatic brain injuries due to other causes.

A case of traumatic acute interhemispheric subdural hematoma due to injured dural branch of anterior cerebral artery

Background:

The precise causes of traumatic acute interhemispheric subdural hematoma (AISDH) are unclear in most cases, and there are few cases, where the sources of bleeding are directly confirmed intraoperatively. We report a rare case of traumatic AISDH, in which a damaged dural branch of anterior cerebral artery (ACA) to the cerebral falx was identified as the cause of bleeding during hematoma removal.

Case Description:

A 61-year-old man with a history of craniotomy for the left putaminal hemorrhage at the age of 50 fell from a bed, bruised his head, and lost consciousness. Computed tomography of the head showed AISDH of 2.5cm in thickness, which was removed through a parietal parasagittal craniotomy under the microscope. Intraoperatively, the bleeding source was revealed to be a damaged dural branch from ACA to the cerebral falx. There was no rebleeding during his stay in our hospital.

Conclusion:

In this case, intraoperative findings revealed that the cause of bleeding was a damage to the dural branch of ACA. A vascular study is mandatory to rule out a vascular malformation in similar cases.