Rapid Spontaneous Resolution of the Acute Subdural Hematoma: Case Series and Review of Literature

BACKGROUND: Traumatic acute subdural hematoma (ASDH) is an oft encountered entity in neurosurgery. While resolution of such thick SDHs usually takes time, certain cases of rapid spontaneous resolution have also been reported. This article attempts to review the pathophysiology, clinical and radiological features of such cases, as well as provide an insight into decision making for their management. METHODS: Electronic literature search was done to look for similar cases of spontaneous rapid resolution of ASDH. Five of authors cases have been described. Their clinical and radiological features along with those of cases from literature search were tabulated and analyzed. RESULTS: A total of 44 relevant cases were included for analyses. Of these, 39 cases were from 33 articles found in existing literature and 5 cases were from author's collection. The M:F ratio was 25:19 with a mean age was 41.84(SD-4.094) years. Twenty -six patients showed “Rapid” neurological improvement (</= 24 hours) while “gradual” neurological improvement (>24 hours) occurred in 10 patients. The mean hematoma resolution time on CT scan was 13.78 hours (SD 16.46) ranging from 1- 72 hours. Twenty-nine patients showed redistribution of hematoma, most commonly to tentorium and falx cerebelli. CT scan findings were classified into 5 types as per the nature of hypodensity around hematoma. The geometric mean time to resolution of hematoma was least for type 2 (7.27 hours) and type 1(7.52 hours) patients. CONCLUSION: Selected patients of ASDH with rapid neurological improvement and specific CT findings may show spontaneous resolution of ASDH. Multicentric studies with larger study population may provide better insight into the nature and outcomes of such entities.