Abstract: Objective To assess the value of 1H-magnetic resonance spectroscopy(1H-MRS) in evaluating cerebral vasospasm resulting from subarachnoid hemorrhage(SAH).Methods Six dogs were subjected to autologous non-heparinized blood injection via cisternal puncture twice at one-day interval to establish models of SAH,and another 6 received injections with normal saline in an identical manner.1H-MRS scan was performed on the 3rd,7th and 14th days after the injections to measure the changes of N-acetylaspartate(NAA),creatine(Cr) and choline(Cho).After the 1H-MRS scan,all the dogs underwent brain digital subtraction angiography(DSA) for determining the basilar artery diameter.Results DSA results on day 3 presented development of obvious vasospasm of the basilar artery,which was most evident on day 7 and recovered obviously on day 14.1H-MRS results demonstrated obvious changes of NAA,Cho and Cr on days 3 and 7 in SAH model group,and NAA declined to the lowest level on day 3 followed by gradual ascending till reaching the normal level on day 14.Cho decreased slightly on day 3,then increased and reached the peak level on day 7 and then decreased.Cr rose steadily from day 3 to 14,but since day 7,the rise slowed down obviously and Cr maintain a level not significantly different from that on day 14(P>0.05).The functional results of 1H-MRS were consistent with the DSA results.Conclusion 1H-MRS can be used to monitor the development of cerebral vasospasm resulting from SAH as a good evaluation method for functional imaging.