الفهرس 
Introduction & Aim of the workOnly 14 pages are availabe for public view
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Abstract
Summary and conclusion
Thyroid nodules are very common in adults,
found in 4–8% by palpation, in 10–41% by
ultrasonography (US), and in 50% by pathologic
examination at autopsy most nodules are benign,
with less than 5% of them being malignant.
Solitary thyroid nodule is defined as discrete
mass, greater than or equal to 1 cm in diameter
which occur in up to 4% of the population and are
most often found in patients 30 to 50 years of age
Surgery and radioiodine therapy have been
the mainstay of therapy in the compressive thyroid
nodules, but surgical complications have been
reported in around 7–10% of cases as well as repeat
surgery in the central or lateral compartments of
the neck may be difficult because previous neck
dissection may be associated with high rates of
morbidity.
The non-invasive and percutaneous methods
like Ethanol ablation and Radiofrequency ablation
are good alternatives to benign solid thyroid
nodules, especially in patients refusing surgery and
those with cosmetic problems.
EA is effective in treatment of benign cystic
thyroid nodules, but is less effective when used to
treat benign solid thyroid nodules.
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–Preprocedural US examination should be
performed to evaluate thyroid nodules and to plan
EA ablation:
Size
Volume calculated by the following
equation: V = πabc / 6, where V is volume, a
the largest diameter and b and c the other
two per pendicular diameters.
characteristics of the nodules
Composition
Vascularity
Presence of abnormal lymph nodes in the
neck
Relationship between the target nodule
and critical neck structures
Three-method approach used in EA: Transisthmic
approach(the best to use in EA), lateral
approach and Cranio-caudal (longitudinal)
approach.
Trans-isthmic approach is the best approach
for EA technique that allows clear continuous
ultrasound monitoring of the relations of the
nodule, the needle and expected location of the
recurrent laryngeal nerve, thus minimizing the
risks of chemical injury to that nerve or the
esophagus
The data regarding use of EA in solid nodules
is variable and depends on the nodule size, volume
of ethanol instilled, and nodule toxicity. Recently
published study, however, demonstrated a success
rate of 60% in solid nodule
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US findings of successful ablation:
Loss of intranodular vascular signal in
Doppler US examination.
Decreased nodule volume. Decreased
echogenicity of the ablated nodule.
Changes in size, echogenicity, and
intranodular vascularity of the nodule should
be evaluated on follow-up US examinations.
Volume reduction (VR) is calculated using the
following equation:
-VR(%)= {initial volume (ml)- final volume (ml}
x100 / initial volume
Conclusion:
• For cystic thyroid nodules EA is superior to
RF ablation with respect to the mean number
of treatment sessions required (1.2 vs. 1.7)
and cost. Therefore, EA may be an
appropriate first-line treatment for cystic
thyroid nodules.
• For predominantly cystic thyroid nodules
(90% > cystic portion >50%) RF ablation can
be used for initial treatment of thyroid
nodules with >20% solid Component.
• For predominantly solid thyroid nodules
(solid portion >50%), EA is much less effective
than is RF ablation. Although additional
application of EA to predominantly solid
nodules may achieve efficacies similar to
those obtainable with RF ablation.