Clinical And Experimental Study Of Early Diagnosis Of Cerebral Lnfarction With Near-infrared Spectroscopy

Objective:To verificate the NIRS's action of early diagnosis of cerebral infarction through monitoring the changes in the contents of blood and blood oxygen of the cerebral tissue in rats and the patients with local cerebral infarction with Near-infrared Spectroscopy (NIRS).Methods:1 .Establishment of local cerebral infarction model in rats and signal collection of the contents of blood and blood oxygen of the cerebral tissue: (1) Experiment group(n=16): The common carotid aretry, internal carotid artery and external carotid artery were separated, and the external carotid artery was ligated. The retrograde intubating into external carotid artery was experformed with 24# trochar, through which 0.2ml saline and 5/0 silk segment were injected in the internal carotid artery. The establishment of animal models was observed through selective carotid digital subtraction angiography (DSA). In succession, a NIRS was used to monitor and record the contents of blood and blood oxygen. To draw a conclusion, we did correlation function analysis and medical statistical processing. (2)Control group(n=16) was injected 0.2mlsaline. The brain tissues of animals in each group were taken for histological examination after experiment.2. 15 cases with sideway cerebral infarction were detected and recorded the bilateral contents of blood and blood oxygen with NIRS and medical statistical processing is done to draw a conclusion. 15 health volunteer were monitored as control group.Results:1. The contents of blood-oxygen in rats of experiment group were 1.000 ?0.000 and 0.840 ?0.065 respectively before and after local cerebral infarction (PO.01); the blood contents in rats of experiment group were 0.000 ±0.000 and 0.218±0.090 respectively before and after local cerebral infarction (P<0.01). No changes were observed in the control group in the contents of blood or blood oxygen before and after injecting saline (P>0.05).2. The contents of blood-oxygen in patients with local cerebral infarction were 1.000±0.000 and 0.760 ±0.057 respectively in the normal side and infarction side (P<0.01); the blood contents in the patients with local cerebral infarction were 0.000 ±0.000 and 0.216 ±0.103 respectively in the normal side and infarction side (PO.01). The content of blood-oxygen in right side is lower than that in left side by (3.5±8.7)% (P<0.01)in the control volunteers and there is not significantly difference in blood content (P>0.05).Conclusions:1. The local cerebral infarction model in rats can be established byinjecting the silk segment into internal carotid artery.2. The cerebral infarction can be early diagnosised by NIRS and the software used in the present study, which was designed by ourselves, is convenient to detecting the cerebral infarction.3. In the early period after local cerebral infarction, the content of blood-oxygen decreases but that of blood content increases in the brain.4. NIRS is a real-time, non-invasive method to detect the changes in the contents of blood and blood oxygen in the cerebral tissue.