Abstract
Thyroid nodular goiter is a prevalent condition requiring imaging for diagnosis and management. Ultrasonography and thyroid scintigraphy are commonly used modalities, but their comparative diagnostic roles remain unclear. To compare ultrasonography and thyroid scintigraphy findings in nodular goiter patients, evaluate correlations between thyroid uptake and blood flow indices, and assess the role of imaging in determining thyroid and nodule size. A cross-sectional observational study conducted from January to November 2021 at the radiation and isotopes center Khartoum. The study included 100 adult patients (86% female, 14% male) with nodular goiter, aged 19 to 70 years (mean: 39.26 ± 14.19 years), randomly selected. Ultrasonography was performed using a high-frequency linear transducer (6-15 MHz) to evaluate thyroid and nodule size, echogenicity, texture, and blood flow indices (resistive index, PI, PSV). Scintigraphy utilized technetium-99m to classify thyroid gland uptake (high, normal, low). Data were analyzed using SPSS; P < .05 was considered significant. Demographics: most participants were aged 19 to 35 (46%) and married (76%). Isoechoic nodules were most common (68%), with 60% showing heterogeneous texture. High uptake was observed in 74% of patients, normal in 10%, and low in 16%. Significant differences were found across uptake categories for resistive index (P = .00), PI (P = .00), and PSV (P = .005). A moderate positive correlation (R² = 0.4075) existed between thyroid size and nodule size. Uptake did not significantly affect thyroid or nodule size. Ultrasonography provided detailed structural and vascular data, while scintigraphy evaluated gland-wide functional activity. Ultrasonography and scintigraphy complement each other in managing nodular goiter. Combining modalities enhances diagnostic accuracy and treatment planning.