Diagnostic ultrasound ( PDFDrive )

CHAPTER 21 The Breast 797
AR
A
B
FIG. 21.56 Fibroadenoma. (A) Classic shape of benign ibroadenomas is elliptical. Such lesions are wider than tall and completely encompassed
by a thin, echogenic capsule. (B) Second most common shape of benign ibroadenomas is gently lobulated. Classic lobulated ibroadenomas have
three or fewer lobulations, are wider than tall, and are completely encompassed by a thin, echogenic capsule.
blood low should be sampled to exclude malignancies such
as invasive ductal carcinoma, lymphoma, or angiosarcoma 56
(Fig. 21.55B).
Parallel (Wider-Than-Tall) Orientation
An oval shape with parallel orientation is the classic appearance
of a ibroadenoma (Fig. 21.56A). An oval mass with gently lobulated
margins containing three or fewer lobulations and parallel
orientation is the second most common shape of ibroadenomas
(Fig. 21.56B). Masses that appear to be circumscribed in one
view and gently lobulated in the orthogonal view are common.
he negative predictive value of the oval shape is 97%, and the
negative predictive value of the gently lobulated shape is 99%,
in a population of masses with 33% malignancy. 45 Despite the
high likelihood of benignity, these masses should always be
followed or biopsy performed to ensure no malignancy is present.
Thin Echogenic Capsule
It is important to combine the circumscribed or gently lobulated
margins with the presence of a complete, thin, echogenic capsule
to minimize false-negative results in circumscribed carcinomas
and in pure DCIS. Although carcinoma has an echogenic
pseudocapsule and DCIS can have an echogenic surrounding
duct wall, they almost never have an elliptical or gently lobulated
shape. In addition, the thin echogenic pseudocapsule that can
be seen around circumscribed carcinomas is oten absent along
part of the surface of the nodule. Carcinoma and DCIS are also
usually associated with other suspicious indings, such as angular
margins, not parallel orientation, microlobulations, or duct
extension. By combining the presence of a complete, thin,
echogenic capsule with the oval circumscribed mass or oval
gently lobulated mass we can achieve a negative predictive value
of greater than 99%. 45
Rocking the transducer in its short axis and heeling and toeing
the transducer along its long axis are oten necessary to demonstrate
the presence of a thin, echogenic capsule along the edges
of the masses. Using less compression oten helps to demonstrate
the thin echogenic capsule in benign masses that are surrounded
by hyperechoic ibrous tissue.
DIAGNOSTIC ULTRASOUND
INDICATIONS
Most diagnostic breast ultrasound is performed in a targeted
fashion to evaluate a particular symptom or mammographic
abnormality.
Symptomatic Breast
Breast Pain
he evaluation of breast pain is based on whether the patient
has focal pain or nonfocal pain. Although focal pain alone
indicates a low likelihood of malignancy, 57 ultrasound is oten
performed to provide reassurance to the patient or to identify
a benign cause that may be treatable. Ultrasound is not