Innate inflammatory responses in stroke: mechanisms and potential therapeutic targets.

Stroke is a frequent cause of long-term disability and death worldwide. Ischemic stroke is more commonly encountered compared to hemorrhagic stroke, and leads to tissue death by ischemia due to occlusion of a cerebral artery. Inflammation is known to result as a result of ischemic injury, long thought to be involved in initiating the recovery and repair process. However, work over the past few decades indicates that aspects of this inflammatory response may in fact be detrimental to stroke outcome. Acutely, inflammation appears to have a detrimental effect, and anti-inflammatory treatments have been been studied as a potential therapeutic target. Chronically, reports suggest that post-ischemic inflammation is also essential for the tissue repairing and remodeling. The majority of the work in this area has centered around innate immune mechanisms, which will be the focus of this review. This review describes the different key players in neuroinflammation and their possible detrimental and protective effects in stroke. A better understanding of the roles of the different immune cells and their temporal profile of damage versus repair will help to clarify more effective modulation of inflammation post stroke.

Malpositioned spinal instrument as a possible cause of superficial siderosis.

STUDY DESIGN: Case report. OBJECTIVE: To report a patient with superficial siderosis as a complication after posterior fixation surgery for odontoid fracture. SETTING: Department of Neurosurgery, Hokkaido University, Japan. METHODS: A 36-year-old man had undergone C1-C2 posterior fixation using lamina hooks for an odontoid fracture in 1997. In 2003, he presented with hearing loss and ataxia; and in 2006, a diagnosis of superficial siderosis was made and spinal instrument malpositioning was detected. RESULTS: The malpositioned instrument, suspected as the cause of superficial siderosis, was removed. CONCLUSIONS: Superficial siderosis of the central nervous system is rare; it results in progressive hearing loss, cerebellar ataxia and pyramidal sign. Chronic hemorrhage in the subarachnoid space precipitates hemosiderin around the cerebellum and brainstem resulting in neurological symptoms. Recurrent hemorrhage and cervical root pathology, for example, root avulsion, are factors; the symptoms worsen gradually and result in hemostasis. Superficial siderosis because of complications from spinal instrumentation surgery is extremely rare. If the instrument is malpositioned in the subarachnoid space, we suggest its removal.

Carotid endarterectomy for internal carotid artery stenosis associated with persistent primitive hypoglossal artery: efficacy of intraoperative multi-modality monitoring.

INTRODUCTION: A persistent primitive hypoglossal artery (PPHA) is a rare vascular anomaly and is usually asymptomatic. However, the PPHA may cause multi-territorial infarction when complicated by internal carotid artery (ICA) stenosis. CASE REPORT: We describe a 73-year-old male who simultaneously developed cerebral infarction in both carotid and vertebrobasilar territories due to ICA stenosis associated with an ipsilateral PPHA. The PPHA mainly provided blood flow to the vertebrobasilar territory in this case, because the bilateral vertebral arteries were markedly hypoplastic. He underwent carotid endarterectomy under internal shunting. Intraoperative multi-modality monitoring including angiography, motor evoked potential, and near infrared spectroscopy was very useful to avoid ischemic complications during surgery. The postoperative course was uneventful. CONCLUSION: It should be reminded that a persistent carotid-basilar anastomosis can cause multi-territorial cerebral infarction mimicking cardiogenic embolism and may be a candidate for aggressive prophylactic intervention, when occlusive lesions develop in the carotid artery. It is very important to monitor hemodynamic and/or electrophysiological status in both carotid and vertebrobasilar territories in order to perform carotid endarterectomy safely in such cases.