A note on the dimensions of the bronchial tree.
نویسنده
چکیده
As Hilding (1949) states, " It is generally assumed that the total cross-sectional area of the [bronchial] tree increases progressively with each successive branching." Having studied the bronchial tree post mortem by slitting open the bronchi and measuring their calibre, Hilding himself believes that the total cross-sectional area of the tree remains almost constant until bronchi of diameter 1.5 mm. are reached. In other words, he regards the respiratory tract not as an everwidening funnel but as a cylinder from the end of which sprout the bronchioles and the respiratory units. The angle at which the daughter bronchi diverge after a bifurcation is of theoretical interest, and there has been much dispute as to the exact mode of branching (summarized by Miller, 1937). Relatively little attention, however, has been paid to the statement of Ewart (1889) that in the proximal part of the bronchial tree " it is an almost invariable rule that of two diverging bronchi the smaller one diverges most from the direction of the parent tube." In the present study an attempt is made to confirm the observations of Hilding and Ewart, using "4 marco " resin casts of a normal adult bronchial tree (Tompsett, 1952). The theoretical implications of their observations will be discussed.
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عنوان ژورنال:
- Thorax
دوره 12 2 شماره
صفحات -
تاریخ انتشار 1957