Introduction: The purpose of this study was to provide pathophysiological evidence for the time window of minimally invasive (MI) procedures for evacuating intracerebral hematoma by observing the perihematomal glutamate level and its correlation with the outcome of the patients treated with MI surgery.
Methods: One hundred consecutive patients with intracerebral hemorrhage (ICH) in the basal ganglia were assigned to either a medical treatment group (MT group, 20 patients) or a minimally invasive treatment group (MI group, 80 patients). The intracerebral hematoma was evacuated using stereotactic MI surgery within 6 hours, 12 hours, 18 hours, or 24 hours of symptom onset based on the interval between the initial hemorrhage to the patients' arrival at the hospital. Perihematomal glutamate levels and brain water content were measured in 10 randomly selected patients in each MI subgroup. The outcome of the patients was determined by the National Institute of Health Stroke Scale (NIHSS) and Modified Ranking Scale (MRS) within 6 months after admission.
Results: The perihematomal glutamate levels and brain water content increased gradually as the intervals from symptom onset to surgery were prolonged. Minimally invasive surgery at all the investigated time points could improve the neurological functions. Performing the MI procedures in 6 hours showed the most remarkable decrease of NIHSS and MRS, and secondarily in 12 hours.
Conclusions: Minimally invasive surgery could be effective in the treatment of patients with ICH. The optimal time window for MI surgery may be within 6-12 hours of symptom onset.