The Journal
may indeed increase with age. The first found
that the depth of the nasopharynx increases
from 3 months to 17 years of age (Subtelny JD
69
1957) . The second of the studies noted that
the nasopharyngeal depth as constant from
infancy to maturity in females but that it
increased moderately from 3 years and 9
months to maturity in males (Handelman CS,
Osborne G 1976) 70 .
A considerable dimorphism appears to exist in
the sagittal growth of the nasopharynx (Linder-
66
Aronson S, Woodside DG 1979, Bergland O)
and although growth in the sagittal depth occurs
in both sexes until 18 years of age, the growth
velocity decreases considerably earlier in girls
(12 years) than in boys (14 years) (Linder-
Aronson S, Woodside DG 1979) 66 . In the latter
study the mean length of the floor of the
nasopharynx was 38.45 mm for boys and 37.40
mm for girls. In both sexes the difference
between the mean length of the floor of the
nasopharynx in the youngest and that in the
oldest group was approximately 4.00 mm. A
meaningful decrease in mean length was
observed in the girls in the oldest age groups.
Although changes in the head posture can alter
the distance between the first cervical vertebrae
and the posterior nasal spine, the length of
straight line joining the anterior arch of the atlas
(AA) and the posterior nasal spine (PNS) has
been used to define the sagittal dimension of
the floor of the nasopharynx (Handelman CS,
70
Osborn g 1976, Ricketts RM 1979) .
Lateral skull radiographs should be taken with
the head in the Frankfort horizontal position, to
standardize dimensions, such as the floor of the
nasopharynx. The use of the AA-PNS distance
to express the length of the floor of the
nasopharynx is in keeping with the
observations of Tobias PV 1981,who states that
the " the lower demarcation of the nasopharynx
is in the plane of the soft palate anteriorly. " This
plane if extended posteriorly usually intersects
the anterior arch of the atlas.
50
The overwhelming majority of studies of the
upper airway are based on the chronologic age
of the subjects studied. One of the cross
71
sectional study by Preston CB 1987 ranked
the data by chronologic age. When the mean
lengths of the nasal floor (ANS-PNS) of the
subjects were ranked according to chronologic
age, the findings of this study were essentially
the same as those reported by Linder-Aronson
and Woodside 1979 66 .
72
Riolo et al 1979 presented data for the
dimension Ba to PNS pertaining to American
eaucasoid children in the age group 6 to 16
years. Unfortunately the definition of the
posterior nasal spine used by the authors was
different from that used in previous studies.
However Riolo et al 72 showed that sexual
dimorphism may be present in the growth, in
depth, of the nasopharynx.
Lymphatic tissue, such as the thymus, shows
rapid growth in infancy and early childhood and
continues to grow at a slower rate until puberty,
after which it gradually decreases in size
(Scammon RE et al 1930) 73 . The classical
lymphoid growth curve of Scammon et al 1930
did not include the measurements of the tonsils
and adenoids. Their growth curve was based on
the weight of the thymus, the number of Peyer's
patches, the number of lymphoid follicles in the
appendix and the weight of the mesenteric
lymphoid tissue. In a sample of white American
children the adenoids reached maximum size
between the ages 9 and 15 years, followed by
subsequent atrophy (Subtenly JD, Koepp-
Baker H; 1956) 74 . This observation, supported
by the findings of Tanner 1962, in white British
juvenile, indicates that growth of the adenoids
follows Scammon's lymphatic growth curve.
75
Linder-Aronson and Leighton 1983 ”, in
contrast to the other authors mentioned, found
that the absolute thickness of the soft tissue on
the posterior nasopharyngeal wall is greatest at
5 years and that it subsequently decreases until
10 years of age.
Vol. 14 No. 2
May-August 2018