Intracranial aneurysms are cerebral vascular aneurysm-like protrusions resulting from abnormal localized vascular changes. Aneurysm rupture and bleeding often results in disability or death of the patient, and survivors can still bleed again.
Age distribution
They are mainly seen in middle-aged people (30-60 years old) and less frequently in young people.
Morphology and size
Aneurysms are broadly classified by morphology as saccular (including spherical, cucurbit and funnel-shaped), spindle-shaped and intermural aneurysms.
Morbidity
Aneurysms are the third most common type of cerebrovascular accident, after cerebral thrombosis and hypertensive cerebral hemorrhage. About 34% of subarachnoid hemorrhages are caused by aneurysms.
Etiology of intracranial aneurysms
The causes of aneurysm formation are summarized as follows: congenital factors, arteriosclerosis, infection, trauma, tumor, etc.
Clinical manifestations
1.Clinical classification
Hunt and Hess classified patients with intracranial aneurysms into five grades according to the risk of surgery.
Grade I Asymptomatic, or mild headache and mild neck stiffness.
Grade II Moderate to severe headache, neck straightness, no neurological deficits except cranial nerve palsy.
Grade III Tired sleep, confusion, or mild focal neurological deficits.
Grade IV Wooden rigidity (Stupor), moderate to severe lateralized incomplete paralysis, possible early decerebrate tonicity and vegetative nervous system dysfunction.
Grade V deep coma, decerebrate tonicity, near death state.
If there are serious systemic disorders such as hypertension, diabetes, severe atherosclerosis, chronic lung disease and severe vasospasm on arteriogram to drop one level.
2.Signs and symptoms
Small, unruptured aneurysms are asymptomatic. The symptoms of intracranial aneurysm can be divided into three categories: bleeding symptoms, focal symptoms and ischemic symptoms.
Diagnosis
Most aneurysms are asymptomatic before rupture, which makes the diagnosis difficult. Persistent focal headaches should be traced to a cause, some of which may be an aneurysm. Only when bleeding occurs or when there are certain focal signs, for example, paresthesia of one side of the motor nerve, will an aneurysm be suspected and various tests will be performed further.
1. Lumbar puncture
When subarachnoid hemorrhage is suspected, lumbar puncture is feasible. The cerebrospinal fluid is mostly pink or blood-colored. Before lumbar puncture, it should be determined whether the patient has increased intracranial pressure and brain herniation.
2.Cranial X-ray plain film
It can detect calcification of aneurysm and bone erosion caused by compression of aneurysm wall.
3.Electron computed tomography scan
CT is useful for determining the extent of hemorrhage, the size of hematoma and cerebral infarction. The site of the hematoma helps to localize the hemorrhagic aneurysm.
Magnetic resonance scan (MRI): It can show the subtle relationship between the aneurysm and the surrounding important structures.
4.Sensory evoked potential examination
Somatosensory evoked potentials are recorded when the median nerve is stimulated.
5.Doppler ultrasonography
It can estimate the blood supply of common carotid artery, internal carotid artery, external carotid artery and vertebral basilar artery before surgery, the direction of blood flow and blood flow after ligating these arteries or after anastomosis of intracranial and external arteries.
6.Cerebral angiography
Final determination of the diagnosis depends on cerebral angiography.
Treatment
Non-surgical treatment
The main objective is to prevent rebleeding and control arterial spasm. It is suitable for the following cases.
①The patient’s condition is not suitable for surgery or the patient’s general condition cannot tolerate craniotomy.
②The diagnosis is unknown and further investigation is needed.
③The patient refuses to operate or the operation fails.
④As an adjuvant treatment before and after surgery.
Prevention of rebleeding includes absolute bed rest, analgesic, antiepileptic, tranquilizer, and laxative drugs to keep the patient quiet and avoid emotional agitation. Antifibrinolytics, control of blood pressure. Prevent and treat cerebral artery spasm. Monitor intracranial arteries with transcranial ultrasound to maintain normal cerebral perfusion pressure. According to the condition, reduce fever, anti-infection, enhance nutrition, maintain water-electrolyte balance, and monitor cardiovascular function. Close observation of vital signs and changes in neurological signs is necessary. Special care needs to be enhanced for comatose patients.
Surgical treatment
Patients with intracranial aneurysm who have subarachnoid hemorrhage should undergo early surgery (clamping of the aneurysm tip or embolization of the aneurysm).