Diagnostic ultrasound ( PDFDrive )

1712 PART V Pediatric Sonography
L
T
A
B
L
T
C
FIG. 50.17 Mesothelioma. (A) Radiograph of young girl with
opaciied left chest. (B) Sonogram shows luid with multiple
echogenic pleural nodules (arrow). (C) Chest CT scan with coronal
reconstruction shows that the mass extends below the diaphragm.
Arrow points to the pleural nodule. L, Lung; T, tumor.
Unlike adults, children may not have typical signs and
symptoms of pneumonia. A common etiological agent for round
pneumonia is pneumococcus (streptococcus pneumonia). he
diagnosis becomes clearer if the radiograph is repeated ater a
few days. On the follow-up radiograph ater antibiotic therapy,
most round pneumonias resolve without progression to lobar
pneumonia.
Ultrasound can show the air bronchograms and conirm that
it is a round pneumonia on the day of the presentation (Fig.
50.23), and one can avoid CT scan of the chest. However, a
follow-up chest radiograph may still be indicated to exclude the
remote possibility of mass or congenital anomaly.
Chest Radiograph or Ultrasound?
Many recent studies have reported that pneumonia can be
diagnosed with ultrasound. 14-25 Ultrasound may supplement chest
radiographs in certain circumstances, such as diferentiation of
round pneumonia from a mediastinal mass (see Fig. 50.23).
However, replacing chest radiographs with ultrasound in suspected
cases of pneumonia is not practical at many institutions. Metaanalysis
14 of eight studies performed from 2008 to 2014 shows
that for most of these studies 15-21 the ultrasound examination
was performed by a skilled physician or skilled sonographer.
hese studies did not specify the time required to perform the
ultrasound examinations and interpret the indings. It is obvious
that the time required to perform an ultrasound study is substantially
longer than to obtain a radiograph. Professional time
involvement of the physician in interpreting ultrasound indings
is typically greater than for interpreting radiographs. Ultrasound
is operator dependent, and interobserver variability has not been
studied. A recent study 22 showed that pneumonia was missed
by ultrasound in 5 of 76 children with pneumonia seen on
radiographs. Missing these 6.6% of pneumonia cases to avoid
minimal ionizing radiation from a chest radiograph probably