Abstract: Objective To evaluate the effect of aneurysm clipping and partial blood clot removal in the subarachnoid space on
hemorrhage volume in the subarachnoid space and cerebral vasospasm in patients with different Fisher grades. Methods
Patients with subarachnoid space hemorrhage (SAH) of Fisher Grades I, II, and III were subdivided into control and treatment
groups for comparative studies. The patients with unruptured intracranial aneurysms (UIAs) undergoing aneurysm clipping
were also compared with Fisher grade I control subgroup. OxyHb levels in the cerebrospinal fluid and cerebral blood flow
volume (CBFV) of the middle cerebral artery (MCA) were measured on days 3, 7, and 13 day after SAH. Results The patients
with UIAs and Fisher Grade I control subgroup showed significant differences in OxyHb levels on day 3 in CBFV of the MCA
on days 3 and 7 (P<0.05). In the SAH groups, OxyHb levels increased significantly on day 3 day in the treatment subgroups of
Fisher Grades I and II, but declined significantly on days 7 and 13 in Fisher Grade III treatment subgroup as compared with
the corresponding control subgroups (P<0.05); in Fisher Grade I group on days 3 and 7 and in Fisher Grade II group on day 7,
CBFV of the MCA increased significantly in the treatment subgroups, but in Fisher Grade III group, CBFV decreased
significantly on days 7 and 13 compared with the control subgroup (P<0.05). A positive correlation was found between OxyHb
levels in the cerebrospinal fluid and CBFV of the MCA (P<0.05). Conclusion For patients with Fisher Grades I and II
aneurysms, craniotomy may increase hemorrhage volume in the subarachnoid space and exacerbate cerebral vasospasm, but
for Grade III patients, aneurysm clipping and blood clot removal shows beneficial effects in terms of reducing hemorrhage
volume and relieving cerebral vasospasm.