Pediatric emergency medicine trisk 946
Bạn đang xem bản rút gọn của tài liệu. Xem và tải ngay bản đầy đủ của tài liệu tại đây (224.1 KB, 4 trang )
FIGURE 116.19 Meckel diverticulum. Anterior image at 30 minutes shows an oval focal
accumulation of 99mTc-pertechnetate in the right lower quadrant of the abdomen (arrowhead ).
INTRA-ABDOMINAL MASSES
Current Evidence
Intra-abdominal masses may be benign or malignant. Children are often
asymptomatic even when the tumor is large; frequently, the mass is detected by
the caregiver noticing a protuberant or lopsided abdomen.
It is difficult to feel an intra-abdominal mass, as well as outline its limits and its
degree of mobility, if an infant or child is crying. After allowing the child to calm,
the physician should make an effort to palpate the intra-abdominal contents
carefully. These masses can be fragile and prone to rupture; therefore, palpation
of the mass should be done gently and strictly limited to as few examiners as
possible.
Retroperitoneal masses tend to be fixed, whereas masses attached to the
mesentery or omentum are mobile and may be shifted to different locations by the
examiner. Pelvic masses are commonly fixed and often can best be felt by rectal
examination. A presacral mass may narrow the rectum and produce constipation.
Abdominal masses present with various characteristics and may be smooth,
nodular, cystic, or firm.
FIGURE 116.20 Ureteropelvic junction obstruction. A newborn with left flank mass.
Ultrasonography of the left flank shows dilated pyelocalyceal system. The communicating
dilated collecting systems are seen in the periphery of the significantly dilated renal pelvis.
Initial evaluation in the ED may include plain abdominal films and an US.
Ultrasonography can differentiate a cystic flank mass ( Fig. 116.20 ) that could be
a hydronephrotic kidney from a solid tumor such as an adrenal neuroblastoma,
and thus, facilitate the proper referral of the child to either a urologist or a
pediatric surgeon. CT and MRI are superior to other modalities for anatomic
detail, and provide anatomic and physiologic information about organs and
vascular structures. Angiography is indicated for an abdominal mass only if a
precise knowledge of segmental vascular anatomy is required or if interventional
techniques are contemplated.
Sacrococcygeal Teratoma
The presacral sacrococcygeal teratoma is the most common tumor of the caudal
region in children and is more common in females than in males (4:1). Most
tumors are benign and are noted at birth. Tumors in patients beyond neonatal age
have a higher incidence of malignancy. Radiography shows a soft tissue mass that
arises from the ventral surface of the coccyx. Calcifications are present in 60% of
presacral sacrococcygeal teratoma and are more common in benign tumors. US
confirms whether presacral sacrococcygeal teratomas are cystic, solid, or mixed
and can also determine impingement on the urinary tract. CT or MRI are helpful
in confirming the diagnosis, particularly in older children, and demonstrates the
content of a tumor, as well as its extent and bone anomalies. Tumors with more
solid components are more often malignant than those with more cystic
components ( Fig. 116.21 ).
FIGURE 116.21 Presacral teratoma. Computed tomographic section of pelvis with contrast
medium enhancement shows a large cystic mass (arrows ). The mass contains both fat and
calcification, and displaces the rectum anteriorly and laterally, and the bladder anteriorly. B,
Bladder with Foley catheter; C, calcification; F, fat; R, rectum.
Nonmalignant Intra-Abdominal Masses
Fecaloma
