Thyroid tissue: US-guided percutaneous laser thermal ablation.
OBJECTIVE
To evaluate in vivo the safety and effectiveness of percutaneous laser thermal ablation (LTA) in the debulking of thyroid lesions.


METHODS
Twenty-five adult patients at poor surgical risk with cold nodules (n = 8), autonomously hyperfunctioning thyroid nodules (n = 16), or anaplastic carcinoma (n = 1) underwent LTA. One to four 21-gauge spinal needles were inserted with ultrasonographic (US) guidance into the thyroid lesions. A 300-microm-diameter quartz optical fiber was advanced through the sheath of the needle. Nd:YAG laser was used with output power of 3-5 W. Side effects, complications, and clinical and hormonal changes were evaluated at the end of LTA and during follow-up. Linear regression analysis was used to investigate the correlation between energy delivered and reduction in nodule volume. Volume of induced necrosis and reduction in nodule volume were assessed with US or computed tomography.


RESULTS
LTA was performed without difficulties in 76 LTA sessions. After treatment with 5 W, two patients experienced mild dysphonia, which resolved after 48 hours and 2 months. Improvement of local compression symptoms was experienced by 12 of 14 (86%) patients. Thyroid-stimulating hormone (TSH) was detectable in five of 16 (31%) patients with hyperfunctioning nodules at 6 months after LTA. Volume of induced necrosis ranged from 0.8 to 3.9 mL per session. Anaplastic carcinoma treated with four fibers yielded 32.0 mL of necrosis. Echo structure and baseline volume did not influence response. Energy load and reduction in nodule volume were significantly correlated (r(2) =.75, P <.001). Mean nodule volume reduction at 6 months in hyperfunctioning nodules was 3.3 mL +/- 2.8 (62% +/- 21.4 [SD]) and in cold nodules was 7.7 mL +/- 7.5 (63% +/- 13.8).


CONCLUSIONS
LTA may be a therapeutic tool for highly selected problems in the treatment of thyroid lesions.
Pacella
Claudio Maurizio
CM
Departments of Radiology and Diagnostic Imaging, Ospedale Regina Apostolorum, Via San Francesco 50, 00041 Albano Laziale, Rome, Italy. cmpacel@katamail.com
Bizzarri
Giancarlo
G
Spiezia
Stefano
S
Bianchini
Antonio
A
Guglielmi
Rinaldo
R
Crescenzi
Anna
A
Pacella
Sara
S
Toscano
Vincenzo
V
Papini
Enrico
E
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002277:Carcinoma / Q000000981:diagnostic imaging / Q000601:surgery; D005260:Female; D006044:Goiter, Nodular / Q000000981:diagnostic imaging / Q000601:surgery; D006801:Humans; D017075:Laser Coagulation / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D013961:Thyroid Gland / Q000000981:diagnostic imaging / Q000601:surgery*; D013964:Thyroid Neoplasms / Q000000981:diagnostic imaging / Q000601:surgery; D016606:Thyroid Nodule / Q000000981:diagnostic imaging / Q000601:surgery*; D013972:Thyrotropin / Q000097:blood; D016896:Treatment Outcome; D018615:Ultrasonography, Doppler, Color; D018084:Ultrasonography, Interventional
D013972:Thyrotropin