STUDIES OF THE AORTIC ARCH AND ITS RAMIFICATIONS IN THE CHINESE INFANTS / 解剖学报

ABSTRACT

The aortic arch and its ramifications were studied in 76 chinese infant specimens (♂44,♀52)We examined its position,length and circumference and the types of its ramifications. 1.In average,the superior border of infant's aortic arch is situated at the level of the intervertebral disc between the second and third thoracic vertebrae,and the inferior border is situated at the level of the upper one-third of the fourth thoracic vertebra. 2.The medial point between the superior and inferior borders of the aortic arch,in average,is situated at the level of lower one third of the third thoracic vertebra.In the 3 age-groups,1,2 and 3-year old infants,in 76 specimens,we found that the levels of the medial point of aortic arches,corresponding to 6.05,6.10and 6.19 in the 7 th region of the vertebral column respectively,Comparison of this figures with those of the adult revealed that its height in the infant is higher than in the adult. 3.The average lengths of aortic arch of the 3 age-groups of the Chinese infants were 20.6?1.31mm,19.3?0.59mm and 20.8?0.43mm respectively. 4.The circumferences of the aortic arch of the 3 age-groups of the Chinese infants before the aortic arch divided int?the innominate artery,in average,were 35.8?0.86 mm,36.4?1.04 mm and 38.6?0.83 mm respectively,and after dividing into the left subclavian artery,in average,they were 26.1?1.01mm,26.9?1.25 mm and 29.7?0.79 mm respectively. 5.Seven types can be distinguished in the patterns of the ramifications of the aortic arch.One type was not included in the twenty types of the ramification that have been suggested by Chang Wei-lung according to McDdonald and Anson's classification.This new type increases the number of the types of the human aortic arch to twenty one.The seven types viz Type A52.infants,68.42?5.33%.Type B11 infants,14.47?4.03%.Type G 4 infants,5.26?2.56%.Type D1 infant,1.32?1.31%.Type F4 infants,5.26? 2.56%.(One of the four cases is named thyro-thymus trunk).Type BF1 infant,1.32 ?1.31%.(This type was composed of a common trunk,which consisted of the inno- minate and left common carotid,the left subclavian and the thyroidea ima arising from the common trunk.According to De Garis's classification,we combine type B with type F into type BF).Type J3 infants,3.95?2.23%.(This type was more common in infants than in adults). 6.By comparing the types of ramification of aortic arch in 76 specimens with those of the adult,it reveals that the types of the ramifications of aortic arches vary with age.