Progress in the Surgical Treatment of Spontaneous Intracranial Hemorrhage: Focus on Neuroendoscopic Surgery

Abstract

  Spontaneous intracranial hemorrhage, which is classified into intraparenchymal and intraventricular hemorrhage, are caused by hypertension or abnormal vessels, such as arteriovenous malformations and Moyamoya disease. Various types of surgical treatment are performed on patients with spontaneous intracranial hemorrhage. However, how surgical interventions contribute to disease prognosis remains unknown to date. The minimally invasive catheter evacuation followed by thrombolysis (MISTIE) Ⅲ trial, which was a multicenter phase Ⅲ trial, demonstrated that a greater hematoma reduction was associated with a more favorable prognosis, indicating that minimally invasive techniques performed during the acute phase may be useful for the successful treatment of intracranial hemorrhages. Neuroendoscopic surgery, which is also a minimally invasive technique, was recently developed. Surgical candidates for neuroendoscopic surgery at our institution are defined as patients having putaminal hemorrhage with a hematoma of more than 30ml, an intraventricular hematoma with a mass effect, and thalamic hemorrhage causing hydrocephalus, in accordance with the operative criteria of the guidelines of The Japan Stroke Society. Regarding the neuroendoscope, a 2.7-mm or 4-mm rigid scope with a high-definition or 4K camera, together with a flexible scope (fiber or video scope), is used. As a brain retractor, a transparent sheath (Neuroport) is used. For hard hematomas, which are usually detected in patients being treated with anticoagulants or who are receiving dialysis, a large tubular retractor (ViewSite) is used. Furthermore, an important surgical instrument is irrigation suction with a cauterization terminal for monopolar coagulation. For hemostasis, oxidized cellulose with fibrin glue, or the recently developed flowable hemostatic matrix with thrombin are useful. In the wet field, complete hemostasis is possible, and the hematoma cavity and ventricle can be washed using artificial cerebrospinal fluid. For hematomas in the third ventricle or in the posterior part of the lateral ventricle, aspiration using a flexible scope is effective, and third ventriculostomy may also be performed for obstructive hydrocephalus. Our cases of intraventricular hemorrhage indicated that the outcomes of patients with caudate hemorrhage tended to be better than those with thalamic hemorrhage. In cases of bleeding from an abnormal blood vessel, endoscopic surgery should be performed carefully after confirming hemostasis. In the future, more detailed outcome evaluations regarding the higher brain functions of patients, the standardization of operations, development of a flexible scope, and new techniques to stop bleeding from abnormal vessels, such as endoscopic neck clipping in the wet field, are expected to be performed.