Diagnostic ultrasound ( PDFDrive )

1938 PART V Pediatric Sonography
A
B
FIG. 55.15 Osteomyelitis. Longitudinal sonogram of the humerus (H). (A) Thickening and abnormal echogenicity of the soft tissues with luid
along the bone (arrows). (B) Normal side for comparison. S, Superior.
and cortical disruption (Fig. 55.15). Color and power Doppler
sonography show increased low at the margin of the elevated
periosteum in advanced infection. 98-100 Osteomyelitis oten spreads
hematogenously in pediatric patients, so when it is detected in
one location, examination of any other symptomatic areas is
recommended. Some investigators examine all the extremities
in this situation, particularly in infants who are diicult to
assess clinically. Negative ultrasound indings do not exclude
osteomyelitis.
Cat-scratch fever is caused by a gram-negative bacillus and
is characterized by fever and regional, sometimes suppurative,
adenopathy occurring proximal to the afected area—for example,
in the groin related to scratches on the leg or in the epitrochlear
area from scratches on the upper extremity. hese infected nodes
are highly vascular 101-103 (Fig. 55.16). Patients with cat-scratch
disease may also develop hypoechoic hepatic and splenic lesions. 104
Noninfectious Inlammation
Sonography has been used to evaluate and to monitor the efects
of treatment in pediatric patients with arthritis. Synovitis and
efusion are oten seen, and there is increased Doppler signal in
the inlamed, thickened synovium. he cartilage can also be
examined for decreased thickness, increased echogenicity, and
erosive changes. 105-107 Baker cysts occur in these patients, most
oten in the knee, and must be diferentiated from a mass or
deep venous thrombosis.
Trauma
Radiographs are the initial diagnostic modality used in evaluation
of trauma, but sonography is a useful problem-solving tool when
symptoms are present and radiographs are unrevealing. his
applies to abnormalities such as growth plate fracture, sot tissue
injury, and retained nonopaque foreign body.
Sonography is an excellent means to detect a fracture through
the growth plate, particularly in the infant in whom the epiphyses
FIG. 55.16 Cat-Scratch Disease. Enlarged inguinal lymph nodes
(arrows) with increased vascularity (gray areas).
are not ossiied. When searching for a fracture, it is important
to study the bone from all possible angles. In the extremities,
this may mean 360-degree visualization. By careful examination
of the afected area and comparison with the contralateral normal
side, one can conirm fracture indings and assessment alignment.
An avulsion or metaphyseal fracture may be detected that is not
seen radiographically. his can be especially useful in nonaccidental
trauma (Fig. 55.17). he joint can be examined to
diferentiate fracture from dislocation and to diagnose secondary
efusion. Care must be taken to distinguish luid from cartilage
because both are hypoechoic. Passive motion and compression
help to eliminate confusion. With fracture, there is virtually