Table 1. US and ES features of partially cystic nodules.
| US features | Malignant nodules | Benign nodules | P value |
|---|---|---|---|
| Mean size (mm) | 20.0 | 23.4 | 0.395 |
| Age (years) | 41.9 | 47.9 | <0.0001 |
| Sex (male/female) | 29/52 | 16/80 | 0.004 |
| Composition | <0.0001 | ||
| Petaloid shape | 56 | 4 | |
| Papillary shape | 24 | 62 | |
| Spongy form | 1 | 30 | |
| HT (yes/no) | 21/60 | 13/83 | 0.037 |
| Shape | <0.0001 | ||
| Micro-lobulate | 50 | 17 | |
| Angular margin | 2 | 11 | |
| Regular | 29 | 68 | |
| Taller than wide shape | 0.164 | ||
| ≥1 | 28 | 24 | |
| <1 | 53 | 72 | |
| Margin | 0.021 | ||
| Distinct | 47 | 39 | |
| Indistinct | 34 | 57 | |
| Echogenicity | 0.01 | ||
| Hypoechoic | 48 | 35 | |
| Isoechoic | 31 | 58 | |
| Hyperechoic | 2 | 3 | |
| Calcification | <0.0001 | ||
| Microcalcification | 66 | 26 | |
| Macrocalcification | 6 | 9 | |
| No calcification | 9 | 61 | |
| Color Doppler | <0.0001 | ||
| Marked internal flow | 42 | 21 | |
| Peripheral blood flow | 24 | 48 | |
| Alder grade | 0.186 | ||
| Alder grade 0 | 15 | 27 | |
| Alder grade 1 | 35 | 20 | |
| Alder grade 2 | 22 | 18 | |
| Alder grade 3 | 9 | 31 | |
| Peak-systole velocity | 24.8±19.4 | 20.2±11.8 | 0.504 |
| Resistance index | 0.67±0.16 | 0.60±0.15 | 0.104 |
| Elastic features | <0.0001 | ||
| ES 4–5 | 51 | 22 | |
| ES 1–3 | 30 | 74 | |
| SR | <0.0001 | ||
| >2.82 | 55 | 20 | |
| ≤2.82 | 26 | 76 |
US, ultrasound; ES, elastography score; HT, Hashimoto’s thyroiditis; SR, strain ratio.