Abstract:
Purpose/aim: the different techniques, suggesting how we can improve accuracy, and reduce
interobserver variability. We will present our personal
experience and review the literature
Content organization: Thyroid gland examination by palpation is a basic method in the assessment
of thyroid nodules, as firm and anelastic lesions
should be suspected being of malignant nature. On
the other hand, US, despite its high sensitivity for the
detection of thyroid lesion, has limited accuracy to
differentiate benign and malignant lesions. Hypervascularity, irregularity of margins, microcalcifications and hypoechogenicity are the most prominent
features of malignancies however also CDUS has
variable accuracy. To date, FNAC is still considered
the gold standard for optimal characterization of
thyroid lesions, but still in 15% to 25% of cases FNAC
findings can be suspicious and in 5% to 15% of cases
inconclusive. Elastography is a new imaging modality where elastic tissue parameters related to the
structural organization of normal and pathological
tissues are imaged. New tools allowing non-invasive
real-time evaluation of these lesions thus needed.
Thyroid elastosonography has been developed
owing to such a need of a more accurate method
than CDUS. The relationship of tissue elasticity and
hardness to palpability follows the basic principle
that to be palpable, the object must be harder than
the surrounding tissue. Several methods have been
proposed, such as: Elastosonography – based upon
the principle that malignancies have stiff tissues and
that, under compression, the softer parts of tissues
deform easier than the harder parts. The force of
compression can be provided either directly by the
operator’s hand, or by the carotid artery pulsation,
or by using shear waves. The evaluation of stiffness
can be qualitative with a color coding system or
quantitative with off line measurements. Elastography has showed good diagnostic values both with
qualitative and quantitative modalities. However,
still some issues may be. How accurate is it? How
reproducible is it? Which role may have in the 3
nodule characterization? We will discuss the different techniques, suggesting how we can improve
accuracy, and reduce interobserver variability. We
will present our personal experience and review of
the literature.
