脳出血とくも膜下出血の治療

We reviewed recent advances in the treatment of hypertensive intracerebral hemorrhage(HIH) and subarachnoid hemorrhage (SAH). The mortality rate of patients with HIH, approximately50% in McKissock’s time (around 1960), was reduced to 20% due to the disseminationof improved diagnostic imaging technologies, advances in medical and surgical treatmentregimens, and an increase in the detection rate of mild cases of HIH. On the otherhand, the mortality rate of SAH patients remained unchanged (approximately 50%) becausepatients experiencing the insult were often of advanced age and because the number ofpatients graded as poor has increased.To treat patients with HIH, we developed a new surgical approach that we call “CT-guidedstereotactic aspiration surgery (SAS)”. We also devised an ultrasonic hematoma aspirator.SAS is beginning to supplant conventional open surgery. SAS may be indicated for patientswith putaminal hemorrhage where the hematoma volume is greater than 30ml, and forpatients with cerebellar hemorrhage with a hematoma volume greater than 15ml. On theother hand, open surgery may be indicated for patients with subcortical hemorrhage wherethe hematoma volume is greater than 40ml. It is not indicated for patients with pontine andthalamic hemorrhage. The efficacy and safety of SAS in patients with pontine and thalamichemorrhage remain to be determined and to our knowledge, no randomized study of role ofSAS in patients with HIH has been reported. Such a study (Surgical Trial in IntracerebralHemorrhage, STICH) is planned in the UK to ascertain operative indications.There have been some advances with respect to diagnostic equipment and the managementof SAH. Three-dimensional CT angiography (3D-CTA), using a helical CT scan, andmagnetic resonance imaging angiography (MRA) have yielded superior images of cerebralaneurysms when compared with digital subtraction angiography (DSA). The titanium clipmarkedly reduces metallic artifacts on CT images. The complete clipping of aneurysms withtitanium clips can be ascertained by postopertive 3D-CTA. A recent Japanese cooperativestudy revealed a decrease in the mortality rate of SAH patients graded as poor. However,grade V patients (World Federation of Neurological Surgery) continue to have a poor outcome.Mild hypothermia induced with indomethacine, an antagonist of cyclooxygenase,may improve the treatment outcome. The cumulative rate of rupture of cerebral aneurysmswas estimated at approximately 1 - 2% per year, however a recent paper shows it tobe 0.05% per year. An unruptured cerebral aneurysms study (UCAS Japan) will start nextyear in Japan. It will reveal ruptre risk and the risks inherent in surgical intervention inpatients with unruptured cerebral aneurysms.