Measurements of the subthalamic nucleus in SUDC brains using TSE MRI contrast (n = 11)a
| Measurement/Dimension/Plane | Right | Left | Differenceb | P Valuec | COVd |
|---|---|---|---|---|---|
| Lengthe (mm) | |||||
| Anteroposterior | 9.6 ± 0.9 | 9.9 ± 0.8 | −0.3 ± 0.6 | .084 | 8.8% |
| Mediolateral | 4.2 ± 1.2 | 4.1 ± 1.0 | 0.0 ± 0.4 | .910 | 26.0% |
| Superoinferior | 6.0 ± 0.6 | 5.8 ± 0.7 | 0.2 ± 0.3 | .047 | 10.8% |
| Anglef | |||||
| Coronal | 58.7° ± 6.5° | 58.0° ± 6.6° | 0.7° ± 5.8° | .414 | 10.9% |
| Axial | 135.5° ± 4.8° | 131.6° ± 5.8° | 3.8° ± 5.9° | .590 | 4.1% |
| Sagittal | 26.5° ± 6.6° | 28.5° ± 7.0° | −1.9° ± 5.4° | .188 | 24.3% |
| Stereotactic coordinatesg (mm) | |||||
| Lateral | 13.5 ± 1.0 | 13.5 ± 1.1 | 0.1 ± 0.5 | 1.000 | 7.8% |
| Posterior | 4.8 ± 0.6 | 4.7 ± 0.5 | 0.1 ± 0.3 | 1.000 | 11.1% |
| Inferior | 5.5 ± 0.9 | 5.4 ± 0.7 | 0.1 ± 0.5 | 1.000 | 14.7% |
Note:—COV indicates coefficient of variation.
↵a Data are means ± standard deviation unless otherwise indicated.
↵b Right-sided measurement minus left-sided measurement.
↵c Paired-sample Wilcoxon signed rank test.
↵d Global COV for right and left data combined (n = 22).
↵e Largest dimension in each plane.
↵f The angle formed by the long axis of the subthalamic nucleus relative to the orthogonal imaging plane where angulation is inferomedial to superolateral in the coronal plane, anteromedial to posterolateral in the axial plane, and anterosuperior to posteroinferior in the sagittal plane.
↵g Coordinates relative to the intercommissural point where the most inferior, lateral, and posterior point of the subthalamic nucleus forms a distinct border with the inferior portion of the zona incerta. This point will usually be inferior and lateral to the desired DBS electrode tip target but can be measured precisely to assess individual and right-left variation in the subthalamic nucleus position.