a Department of Surgery , The University of Hong Kong , Hong Kong SAR , PR China.
b Department of Medicine , The University of Hong Kong , Hong Kong SAR , PR China.
Int J Hyperthermia. 2017 Dec;33(8):875-881. doi: 10.1080/02656736.2017.1318456. Epub 2017 Apr 24.
High intensity focused ultrasound (HIFU) is a promising ablation technique for benign thyroid nodules. However, its effect on underlying thyroid function remains unknown. We aimed to evaluate the 6 months changes in serum thyroid stimulating hormone (TSH) and free thyroxine (FT4) after HIFU treatment.
Eighty-three consecutive patients who underwent single HIFU ablation for symptomatic benign thyroid nodule were analysed. Eligible patients had serum TSH and FT4 checked before treatment (baseline), 1 week, 3 and 6 months following HIFU treatment. Primary endpoints were hypothyroidism (FT4 < 12 pmol/L) and hyperthyroidism (FT4 > 23 pmol/L) in the 6 months following treatment. To express extent of nodule ablation relative to the total gland volume, an ablation volume ratio was calculated by [(Ablated nodule volume/total thyroid volume)/(total thyroid volume)] × 100.
Relative to baseline, 1-week serum TSH significantly dropped (from 1.16 to 0.76 mIU/L, p < 0.001) while 1-week serum FT4 significantly rose (from 16.0 to 17.8 pmol/L, p < 0.001). However, 3- and 6-months TSH and FT4 did not changed significantly from baseline (p > 0.05). No patients developed hyperthyroidism while one (1.4%) developed hypothyroidism (FT4 = 11 pmol/L) at 3 months and 6 months. Interestingly, this patient had a previous lobectomy and an ablation volume ratio of 64.00%.
Hypothyroidism following single HIFU ablation occurred rarely (1.4%) and resulted in little clinical relevance. Given that only one patient developed hypothyroidism following single HIFU ablation, it remains unclear how patients with different amount of parenchyma and relative extent of ablation may affect subsequent thyroid function.
高强度聚焦超声（HIFU）是一种有前途的良性甲状腺结节消融技术。然而，其对潜在甲状腺功能的影响尚不清楚。我们旨在评估 HIFU 治疗后 6 个月血清促甲状腺激素（TSH）和游离甲状腺素（FT4）的变化。
分析了 83 例因良性甲状腺结节症状而行单次 HIFU 消融的连续患者。合格的患者在治疗前（基线）、HIFU 治疗后 1 周、3 个月和 6 个月检查血清 TSH 和 FT4。主要终点是治疗后 6 个月发生的甲状腺功能减退症（FT4<12 pmol/L）和甲状腺功能亢进症（FT4>23 pmol/L）。为了表达相对于总腺体积的结节消融程度，通过 [(消融结节体积/总甲状腺体积)/(总甲状腺体积)]×100 计算消融体积比。
与基线相比，血清 TSH 在 1 周时显著下降（从 1.16 降至 0.76 mIU/L，p<0.001），而血清 FT4 在 1 周时显著升高（从 16.0 升至 17.8 pmol/L，p<0.001）。然而，3 个月和 6 个月时 TSH 和 FT4 与基线相比无明显变化（p>0.05）。没有患者发生甲状腺功能亢进症，而有 1 例（1.4%）在 3 个月和 6 个月时发生甲状腺功能减退症（FT4=11 pmol/L）。有趣的是，该患者曾行单侧腺叶切除术，消融体积比为 64.00%。
单次 HIFU 消融后发生甲状腺功能减退症的情况很少见（1.4%），且临床相关性较小。鉴于单次 HIFU 消融后只有 1 例发生甲状腺功能减退症，尚不清楚不同数量的实质组织和相对消融程度如何影响随后的甲状腺功能。
