目的：早产儿脑组织CT值普遍较低，难以判断是否为正常范围。该文探讨早产儿正常脑组织CT值与足月儿脑组织CT值的差异。方法：对76例早产儿(按胎龄分为28～33+6周早产儿36例及34～36+6周早产儿40例)及50例正常足月新生儿(胎龄为37～42足周)进行头颅CT检查并测定各部位脑组织CT值。结果：28～33+6周早产儿和34～36+6周早产儿小脑、脑干、基底节、丘脑、白质、灰质CT值均低于足月儿相应部位脑组织CT值，其差异有显著性(P<0.01)。28～33+6周早产儿不同部位脑组织CT值均低于34～36+6周早产儿相应部位脑组织CT值，其差异有显著性(P<0.01)。结论：早产儿脑组织CT值明显低于足月新生儿，故早产儿脑组织CT值有自己的正常值范围

OBJECTIVE: The CT values of brain tissue of premature infants are usually low and it is difficult to assess if they stand in the normal range of CT values of premature infants. This paper aims at studying the differences of brain CT values between the premature and term infants. METHODS: Seventy six premature infants were divided into 2 groups according to the gestational age: 28-33 +6 weeks group (n=36) and 34-36 +6 weeks group (n=40). Fifty term infants were used as the control group. The cranial CT scan was taken and the CT values of various regions of brain tissues were measured. RESULTS: The CT values of cerebellum, brainstem, basal segment, thalamus, white matter and grey matter in the two premature infants groups were significantly lower than those in the control group (P< 0.01 ). The CT values of the above regions of brain tissues in the 28-33 +6 weeks group were significantly lower than those in the 34-36 +6 weeks group (P< 0.01 ). CONCLUSIONS: This study shows that the brain CT values of the premature infants are significantly lower than those of the term infants, thus the reference range of the brain CT values of full term neonates is not fit for the premature newborns.