Table 2. Ranking of top 10 active countries/regions and institutions in search of the 4D flow MRI field from 2003 to 2022.
| Ranking | Country/region | Frequency | Centrality | Institution | Frequency | Centrality |
|---|---|---|---|---|---|---|
| 1 | USA | 498 | 0 | Northwestern Univ | 171 | 0.17 |
| 2 | Germany | 221 | 0.9 | Univ Wisconsin | 92 | 0.17 |
| 3 | Netherlands | 119 | 0.31 | Stanford Univ | 64 | 0.38 |
| 4 | England | 108 | 1.01 | Leiden Univ | 60 | 0.11 |
| 5 | Sweden | 105 | 0.45 | Linkoping Univ | 53 | 0.34 |
| 6 | Japan | 89 | 0.08 | Univ Calif San Francisco | 40 | 0.44 |
| 7 | Switzerland | 80 | 0.94 | Kings Coll London | 36 | 0.11 |
| 8 | China | 60 | 0 | Univ Calgary | 32 | 0.15 |
| 9 | Canada | 52 | 0.24 | Lund Univ | 30 | 0.05 |
| 10 | France | 48 | 0.72 | Univ Zurich | 28 | 0.33 |
4D flow MRI, 4-dimensional flow magnetic resonance imaging.