Acute Interhemispheric Subdural Hematoma: Two Case Reports and Analysis of the Literature

Abstract

Interhemispheric subdural hematoma (ISH) had been considered extremely rare until identification with imaging studies. Its natural history is still quite unknown in terms of potential origin and course. As a consequence of various controversies, there is still no clearly established treatment, particularly in regard to medical or surgical management. The best decision requires tailoring treatment to the individual patient according to his or her clinical condition. Two patients with acute interhemispheric subdural hematomas are reported, the controversial management of this rare entity is analysed. In reviewing current published cases of interhemispheric subdural hematoma, it seems that the outcome of an individual patient is not related to the therapeutic approach, but to the level of consciousness and the neurological condition on admission. Surgical and medical treatment indications are taken into account for management. A patient with ISH developed an extension of the hematoma to the convexity at 2 weeks of his clinical course, with a decline of his neurological condition. The hematoma was then evacuated through a parietal craniotomy with an uneventful postoperative course. Another case of ISH presented as headache and TIA, with spontaneous clinical improvement at 12 hours and with no decline in the patient's neurological condition. Management was conservative. In both cases the neurological examination was normal after 6 months. As in previously reported cases, the clinical and neurological condition of the patient on admission is crucial for the course of an ISH. Treatment strategies are based on the individual neurological response of each case and the risk-benefit ratio to decide on a medical or surgical approach.

Traumatic interhemispheric subdural haematoma: Study of 35 cases

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] It accounts for approximately 6% of all traumatic SDH. 1 Head trauma is estimated to comprise 80-90% of the aetiology of ISH.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13] We have treated 35 patients with traumatic ISH, and have retrospectively investigated the association between clinicoradiological findings and outcomes in these patients. This study represents the largest series of such patients to be reported and the first analysis of the prognostic factors in patients with traumatic ISH.…”

Interhemispheric Subdural Hematoma Presenting with Falx Syndrome after Trauma

“…The overall mortality rate of ISH is 24-27% 2,14) and is independent of the choice of treatment, indicating that one treatment type (surgical or conservative treatment) is not inherently better 9,14) Those supporting surgical intervention insist that an ISH can have a grave prognosis because of the lack of specific signs and the potential for rapid deterioration of consciousness. These clinicians suggest that prompt surgery via a craniotomy is the only way to deal with this condition safely.…”

“…The present state of knowledge gives no definitive indication for surgery in the management of an ISH, with the exception of patients with a large hematoma or rapidly deteriorating level of consciousness despite medical treatment. 9) An ISH is frequently small and often does not require surgical evacuation. In such cases, the natural history of the ISH tends toward spontaneous reabsorption and recovery of the neurological deficits, which can be followed by serial CT scans.…”

“…2,4) The clinical picture of ISH often comprises a falx syndrome characterized by monoparesis of the lower extremity, or hemiparesis in which the leg is weaker than the arm. 9,10) Other symptoms may include headache, vomiting, seizures, dementia, language disturbance, oculomotor nerve palsy, or loss of consciousness. 5,13) One case of ISH and tentorial hemorrhage presenting with visual disturbances has been reported.…”