Comparative analysis of the spectrum of imaging findings across the 18q chromosome abnormalities
| 18q- Group (n = 23) | Ring chromosome 18 Group (n = 4) | Trisomy 18 Group (Trisomy 18 n = 7, Tetrasomy 18 n = 1) | P Value | |
|---|---|---|---|---|
| Number of MRIs (n = 49) | 34 (69) | 5 (10) | 10 (21) | - |
| Age at MR imaging | 51.8 (17.8–114.4) | 18.1 (14.9–212.2) | 6.8 (0.17–43.7) | .06 |
| Abnormal white matter | 25 (74) | 5 (100) | 5 (50) | .11 |
| PMD-like pattern | 4 (12) | 1 (20) | 2 (20) | .37 |
| Intermediate pattern | 7 (21) | 2 (40) | 2 (20) | |
| Washed-out pattern | 14 (41) | 2 (40) | 1 (10) | |
| Normal | 9 (26) | 0 | 5 (50) | |
| Myelination lag | 17.2 (3.3–19.6) | 27.0 (19.2–33.0) | 9.0 (3.0–15.1) | .005 (18 ring vs 18 trisomy) .03 (18 ring vs 18q-) |
| Multifocal white matter hyperintensities | 0 | 3 (60) | 1 (10) | .001 (18 ring vs others) |
| APD pons (mm) | 18.5 (16.9–19.4) | 15.3 (15.2–19.5) | 13.0 (10.4–17.3) | .002 (18 trisomy vs 18q-) |
| Pons APD <3rd percentile | 3 (9) | 0 (0) | 7 (70) | <.001 (18 trisomy vs others) |
| Pons/FOD ratio | 0.13 (0.12–0.14) | 0.13 (0.12–0.14) | 0.11 (0.10–0.12) | .002 (18 trisomy vs 18q-) .02 (18 trisomy vs 18 ring) |
| CCD vermis (mm) | 41.8 (37.1–45.7) | 38.8 (36.8–43.5) | 27.6 (19.4–35.0) | <.001 (18 trisomy vs 18q-) |
| CCD vermis <3rd percentile | 7 (21) | 0 (0) | 7 (70) | .003 (18 trisomy vs others) |
| CCD vermis/FOD ratio | 0.30 (0.27–0.33) | 0.31 (0.30–0.35) | 0.23 (0.19–0.25) | <.001 (18 trisomy vs 18q-) .002 (18 trisomy vs 18 ring) |
| TCD (mm) | 88.4 (81.7–94.3) | 78.2 (72.2–87.9) | 63.9 (47.6–88.3) | .04 |
| TCD/FOD ratio | 0.65 (0.59–0.68) | 0.63 (0.59–0.72) | 0.56 (0.49–0.63) | .06 |
Note:—Numbers in brackets indicate percentages and interquartile range as applicable.