To discuss different onset patterns of middle cerebral aneurysm so as to enhance its clinical diagnostic accuracy in hospitals at primary level, and reduce misdiagnosis and mistreatment.

The clinical data of 116 cases of patients with middle cerebral artery aneurysm (MCAA) hospitalized and treated in Xing’an League People’s Hospital from January 2007 to January 2019 was reviewed, in which 87 patients were hospitalized for aneurysm rupture-caused intracranial hemorrhage, the other 29 discovered by accident asymptomatically. Among cases with hemorrhage, 41 were with subarachnoid hemorrhage, 24 accompanied by intracerebral or subdural hematoma, 7 with cerebroventricular hemorrhage, and 15 intracerebral hematoma only. The aneurysms were located in 123 cases of M1 segment ,1 case of M2 segment and 1 case of M3 segment.

A total of 125 MCAA were found in 116 patients, of which 76 received surgical treatment clamped by one or more aneurysm clips; 5 with thrombosis aneurysm were removed of the thrombus and part of the tumor body. After surgery, modified Rankin score was 0 of 35 cases, 1 in 11 cases, 2 in 12 cases, 3~4 in 8 cases, 5 in three cases. Seven patients died despite all rescue measures.

MCAA is a common intracranial aneurysm. Unruptured MCAA can be easily neglected in general clinical examination. We need to distinguish it from meningioma. The ruptured type takes the form of not only subarachnoid hemorrhage, but also hematoma in lateral fissure pool, intracerebral hematoma, subdural hematoma, total intraventricular hemorrhage, etc, which should be differentiated carefully with hypertensive intracerebral hemorrhage in clinical practice to avoid misdiagnosis and missed diagnosis.