Diagnostic ultrasound ( PDFDrive )

1872 PART V Pediatric Sonography
Hydrosonourethrography may be used to detect anterior
urethral abnormalities (strictures, calculi, anterior or posterior
urethral valves, foreign bodies, bladder neck dyssynergia,
diverticula, trauma) by scanning the penis with a linear array
transducer during real-time observation during voiding or during
a retrograde hand-injection of saline into the urethra. 15 Postvoid
scanning of the bladder can provide information about bladder
function, diferentiate the bladder from cystic masses or luid
collections in the pelvis, and evaluate the degree of drainage
from dilated upper urinary tracts. When children cannot void,
ilms taken ater a Credé maneuver or catheterization indicate
the efectiveness of these bladder-emptying procedures. We
measure the postvoid residual of the bladder using the following
formula:
Length × Width × Depth ( in cm) ÷ 2 = Volume ( in mL)
FIG. 54.3 Normal Trigone. With meticulous scanning, it is possible
to identify the trigone (arrows) in pediatric patients.
NORMAL FEMALE ANATOMY
The Uterus
he uterus and ovaries undergo a series of changes in size and
coniguration during normal growth and development. 5,13 he
newborn female uterus is prominent and thickened with a
brightly echogenic endometrial lining caused by in utero hormonal
stimulation 16 (Fig. 54.5). In the irst 3 days of life, mean length
and mean volume of the uterus are 4.2 cm and 10.0 cm 3 . 17 he
uterine coniguration is spade shaped with a fundus-to-cervix
ratio of 1 : 2. At 2 to 3 months of age the prepubertal uterus
regresses to a smaller size and lat coniguration (Fig. 54.6), with
a length of 2.5 to 3 cm and a fundus-to-cervix ratio of 1 : 1, and
with the endometrial stripe (when seen) appearing as thin as a
pencil line. his tubular uterine coniguration is maintained until
puberty. he postpubertal uterine length gradually increases
B
B
A
B
C
Urethra
Urethra
D
PENIS SAG VOIDING
E
PENIS SAG VOIDING
FIG. 54.4 Normal Urethras. (A) Normal female urethra. Using bladder (B) as an acoustic window, urethra (arrow) may be seen. (B) Voiding
sonourethrography indings in a female. With use of a sagittal suprapubic approach during voiding, the female urethra can be seen as a luid-distended
structure. (C) Normal posterior urethra in young boy. Transverse scan through moderately distended bladder (B) shows posterior urethra (white
arrow) and prostate gland (black arrowheads) surrounding the urethra. (D) and (E) Voiding sonourethrography indings in a male. Sagittal scan
demonstrating normal-appearing penile urethra in (D), and the normal-appearing, most distal urethra at the fossa navicularis in the glans of the
penis. (C with permission from Rosenberg H. Sonography of the pediatric urinary tract. In: Bush WH, editor. Urologic imaging and interventional
techniques. Baltimore: Urban & Schwarzenberg; 1989. p 164-179. 16 )