🎯 Accuracy
Accuracy is the degree to which a measured or executed result matches the true or intended value. In neurosurgical practice, it refers to the spatial closeness between a planned target and the actual result achieved during surgery or imaging.
✅ Examples in Neurosurgery
- Distance between planned and implanted DBS electrode
- Alignment of image-guided biopsy needle to lesion center
- Registration error in neuronavigation systems
📊 Common Accuracy Metrics
| Metric | Description |
|---|---|
| Euclidean distance | 3D distance from planned to actual coordinates |
| Radial error | Lateral deviation from the target (common in stereotaxy) |
| Targeting error (mm) | Average deviation from planned trajectory |
| % within tolerance | Percentage of cases within acceptable error margin (e.g., <2 mm) |
⚠️ Accuracy vs. Precision
- Accuracy = How close to the target
- Precision = How consistent multiple measurements are
Example: A robot that hits 3 mm off the target every time is precise but not accurate.