Central nervous system disorders

IV./4.6.: Therapy

IV./4.6.1.: Patient groups based on the severity of the symptoms

Subarachnoid hemorrhage patients are divided into groups according to the severity of the symptoms. Based on this classification, surgical therapy or conservative therapy is applied; however, patients in both cases require intensive care treatment. The most commonly used scales are the Hunt-Hess scale and the Grading Scale of the World Federation of Neurological Surgeons (GSWFNS). This latter is based on the score of the Glasgow Coma Scale (GCS) and the presence or absence of the focal neurological deficit. In this classification, patients with the mildest symptoms belong to group I, while in the group V are the seriously ill.

The Hunt-Hess scale also divides the patients into five groups. According to this, patients in group I have only headache; in group II have severe headache with nuchal rigidity; in group III slightly altered consciousness (somnolence or confusion) and neurological signs are present; in group IV deeper alteration of consciousness, hemiparesis or autonomic dysfunction are seen; while patients of group V are in coma and decerebration rigidity is present. By the Hungarian neurosurgical protocol for GSWFNS I-II groups immediate surgical intervention is required, while in IV-V groups delayed intervention is recommended, since the fatality rate of the acute surgery is 80% in the latter case.

The vasoconstriction related delayed ischemia (34%) and the elevated intracranial pressure due to bleeding (25%) are the leading cause of death, while 17% of the cases the aneurysmal rebleeding is the direct cause of death. Early neurosurgical intervention dimishes the chance of rebleeding, which is 4% without surgery in the first 24 hours after the first hemorrhage, and 1.5% in the following two weeks. Considering the high risk of rebleeding in the first 14 days and the fact, that at this high mortality rate the complications of surgery do not deteriorate further the chance of surviving of the patient. In some North American neurosurgical centers, such as in the Cornell University Hospital, immediate intervention is performed in all patient groups.

IV./4.6.2.: Clipping vs. Coiling

In the treatment of subarachnoid hemorrhage two surgical methods are used:

• - microvascular neurosurgery (clipping)

• - or endovascular (coiling) treatment.

The authors of the ISAT (International Subarachnoid Aneurysm Trial) follow-up study compared the outcomes of the two techniques. According to their results, with coiling method, one year after the surgery, the number of asymptomatic patients among the survivors was higher and the developments of seizure was less. However, the frequency of rebleeding was less  and the rate of complete aneurysm occlusion was higher among the patients treated with clipping method.

There are aneurysms which, due to their localization (in deep brain area or in the posterior fossa) are more effectively treated by coiling method while others, due to their morphology (wide neck aneurysms), have better outcome with coiling technique. In summary, the endovascular method is gaining space in recent years as a first choice treatment of bleeding aneurysm.