Ultrasonographic changes of the female bladder neck during development.
BACKGROUND
Our previous study showed that the anteroposterior vesical wall angle (APVA) at the bladder neck on transabdominal ultrasonography varied widely between women. The present study examines whether the APVA changes during development in girls with a normal bladder.


METHODS
Seventy-four females aged 0-29 years with normal bladders were examined by transabdominal ultrasonography. They were divided into six age groups and their APVA was measured in the supine position by sagittal ultrasonography. Intravenous urography was conducted to examine bladder neck descent and bladder neck opening.


RESULTS
The APVA ranged from 85 to 200 degrees. The mean APVA in girls aged 0-4 years was 129 +/- 30 degrees (+/-SD) and the mean APVA in girls aged 5-9 years was 135 +/- 25 degrees. The mean APVA at ages 10-14 years was 161 +/- 26 degrees; at 15-19 years, 164 +/- 33 degrees; at 20-24 years, 164 +/- 18 degrees; and at 25-29 years, 163 +/- 16 degrees. The APVA values of these four groups were significantly larger (P < 0.05) than those of the two younger groups. No bladder abnormalities were found on intravenous urography.


CONCLUSIONS
The APVA was small in some girls under 10 years of age, but the APVA of girls aged over 10 years was similar to that in young adults. The APVA may reflect bladder base plate tone and be partially related to hormonal changes in females during development.
Sugaya
Kimio
K
Department of Urology, Faculty of Medicine, University of the Ryukyus, Okinawa, Japan. sugaya@med.u-ryuku.ac.jp
Nishijima
Saori
S
Oda
Masami
M
Owan
Tomoko
T
Ashitomi
Katsuhiro
K
Miyazato
Minoru
M
Morozumi
Makoto
M
Hatano
Tadashi
T
Ogawa
Yoshihide
Y
D000293:Adolescent; D000328:Adult; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D014463:Ultrasonography; D001743:Urinary Bladder / Q000000981:diagnostic imaging* / Q000254:growth & development*