Diagnostic ultrasound ( PDFDrive )

CHAPTER 20 The Parathyroid Glands 751
A
B
FIG. 20.21 Multimodality Imaging in Recurrent Hyperparathyroidism. (A) Longitudinal sonogram of the right neck in a patient with recurrent
hyperparathyroidism shows two subcentimeter nodules (arrows) along the posterior surface of the thyroid (T), consistent with hyperplastic parathyroid
tissue at the site of previous remote parathyroid resection for multiple gland disease. (B) Corresponding anterior projection from 99m Tc sestamibi
(left image) and iodine-123 (middle image) dual-agent subtraction (right image) coronal SPECT imaging shows two concordant focal areas of increased
activity (arrow).
surgery may be greater with cutting-needle biopsy. FNA biopsy
of suspected parathyroid adenomas is well tolerated, with few
reported complications. 103 Although a theoretic consideration,
parathyromatosis does not appear to be a complication of FNA
biopsy. 137
ETHANOL ABLATION
Sonography can be used to guide percutaneous injection of
ethanol into abnormally enlarged parathyroid glands for chemical
ablation. 138-151 Ethanol ablation is most oten used in postoperative
patients with recurrent or persistent hyperparathyroidism who
have sonographically visible, biopsy-proven hyperfunctioning
parathyroid tissue but who are poor surgical candidates. 141,144,146
Some dialysis patients with secondary hyperparathyroidism and
patients with a history of multigland disease with recalcitrant
recurrent hyperparathyroidism ater previous subtotal surgery
have also received this treatment. 141,146-151 Ethanol ablation has
been shown to be very useful in patients with MEN I who have
had previous subtotal parathyroidectomy and recurrent disease
in their remaining residual half-gland in the neck. 141,152 A portion
of the remaining gland can be ablated with ethanol to control
hypercalcemia and avoid repeat surgery, which has a very high
complication rate of postoperative hypoparathyroidism in these
patients. Autograts in patients with recurrent grat-dependent
hyperparathyroidism can be similarly treated 153 (Fig. 20.24, Video
20.19). Adenomatous hyperplasia with autonomously functioning
glands (tertiary hyperparathyroidism) has also been treated
with ultrasound-guided ethanol injection to reduce gland mass,
but with unpredictable results. 154,155
Ethanol ablation is generally performed under local anesthesia,
typically ater conirmation of parathyroid tissue with FNA biopsy.
Under real-time ultrasound guidance, a standard 25-gauge needle
attached to a 1-mL tuberculin syringe is inserted into the mass.
With the tip in constant visualization, sterile 95% ethanol is
injected into multiple regions of the mass, with a volume about