DEMİRAY Işıl UĞUZ, Fatma Suna KIRAÇ, Olga YAYLALI, Doğangün YÜKSEL

Prognostic role of Tc-99m pertechnetate thyroid scintigraphy prior to fi xed-dose radioiodine therapy of toxic multinodular goiters

Amaç: Bu çalışmanın amacı sabit I-131 dozu ile tedavi edilen toksik multinodüler guatrlı (TMNG) hastalarda tedavi öncesi çekilen Tc-99m perteknetat tiroit sintigrafisinin prognostik rolünü araştırmaktı. Yöntem ve gereç: TMNG nedeniyle 740 MBq I-131 ile tedavi edilen 28 hasta (18 K / 10 E; ortalama ± SD = 63 ± 11 yıl) geriye dönük değerlendirildi. Kayıt edilen veriler tedavi öncesi yaş, Tc-99m perteknetat tiroit sintigrafisi ve ultrason bulguları, antitiroit medikasyon, tiroit hormon profili ve klinik durumu içermekteydi. Anterior tiroit görüntüleri üzerinde sıcak nodüllerinin, tükürük bezlerinin ve geri-planın üzerine ilgi alanları çizildi. Net nodül sayımları, net tükürük bezi sayımları, nodül/tükürük bezi oranları ve nodül/geri-plan oranları hesaplandı. Bu değerler radyoiyot tedavisi sonrası hipotiroidili ve ötiroidili hastalar için istatistiksel olarak karşılaştırıldı. Bulgular: Çalışma grubunda ortalama izlem süresi 7 ± 2 aydı (aralık, 6-12 ay). Bir hastada hipertiroidi, 19 hastada ötiroidi ve 8 hastada hipotiroidi saptadık. Hipotiroidi gelişen hastalarda tedavi öncesi ortalama net nodül sayımları (34,79 ± 14,06 sayım), ötiroidi gelişen hastalarınkinden (26,80 ± 11,04 sayım) anlamlı şekilde daha yüksekti (P = 0,014). Diğer üç parametre iki grup arasında anlamlı farklılık göstermedi. Sonuç: Sabit 740 MBq I-131 dozu ile tedavi edilen TMNG’lı hastalarda tedavi öncesi çekilen tiroit sintigrafisinde hesaplanan sıcak nodülün Tc-99m perteknetat tutulum düzeyi erken hipotiroidizm gelişecek hastaları önceden saptayabilir.

Toksik multinodüler guatrın sabit doz radyoiyot ile tedavisi öncesi Tc-99m perteknetat tiroit sintigrafi sinin prognostik rolü

Aim: To investigate the prognostic role of Tc-99m pertechnetate thyroid scintigraphy pretreatment in patients with toxic multinodular goiters (TMNG) who were then treated with fixed I-131 doses. Materials and methods: We retrospectively evaluated 28 patients (18 females and 10 males; mean ± SD = 63 ± 11 years) that were treated with 740 megabecquerels (MBq) of I-131 for TMNG. Information, including age, Tc-99m pertechnetate thyroid scintigraphy and ultrasonography findings, antithyroid medication, thyroid hormone profile, and clinical status before treatment, was recorded. The regions of interest were drawn over the hot nodules, salivary glands, and the background on the anterior thyroid images. The net nodule counts, net salivary counts, nodule-to-salivary ratios, and nodule-to-background ratios were then calculated. The data were statistically compared for the hypothyroid and euthyroid patient groups after radioiodine treatment. Results: In the study group, the mean follow-up period was 7 ± 2 months (range: 6-12 months). We detected hyperthyroidism in 1 patient, euthyroidism in 19 patients, and hypothyroidism in 8 patients. The pretreatment mean net nodule counts (34.79 ± 14.06 counts) in the patients that developed hypothyroidism were significantly higher than in those patients that developed euthyroidism (26.80 ± 11.04 counts) (P = 0.014). The other 3 parameters did not show signifi cant differences between the 2 groups. Conclusion: The Tc-99m pertechnetate uptake level of hot nodules calculated from the pretreatment of thyroid scintigraphy in patients with TMNG treated with a fixed 740-MBq I-131 dose may predict early hypothyroidism in patients.

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