fMRI activation areas and intraoperative cortical mapping target in the precentral gyrus of 21 patients
| Pain* | Neurological Status |
Quality of iCM |
fMRI |
Comparison of iCM and fMRI |
||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Hypoesthesia Allodynia | Motricity | iCM Target Obtained† | Limitations of iSEP | Limitations of iBS | fMRI Target Obtained† | Analysis Threshold (P Values)‡ | Extent of fMRI Activation, Both Sides§ | Distance between Targets (mm)‖ | Concordance between Targets, Both Techniques¶ | |||
| 1/40/F | Face | TN | + | Normal | Hand + | Electrical artifacts | Electrical artifacts | Hand +++ | <.0001 | Similar extent | 5 | Good: fMRI helped iCM targeting |
| Face 0 | Electrical artifacts | Electrical artifacts | Face not studied | |||||||||
| 2/62/M | UL | ScS | ++ | Plegic | Hand +++ | Plegic | Hand ++ | <.0001 | Healthy side > painful side | 3 | Excellent | |
| 3/65/F | LL | SS | + | Paretic | Hand +++ | Hand +++ | <.0001 | Similar extent | 5 | Excellent | ||
| Foot ++ | Foot ++ | <.001 | Not studied | 8 | Good: fMRIhelped iCM targeting | |||||||
| 4/44/M | UL | ScS | ++ | Plegic | Hand +++ | Plegic | Hand ++ | <.0001 | Healthy side > painful side | 3 | Excellent | |
| 5/33/F | UL | ScS | + | Normal | Hand +++ | Hand +++ | <.0001 | Similar extent | 3 | Excellent | ||
| 6/66/F | UL | ScS | + | Paretic | Hand +++ | Hand +++ | <.0001 | Similar extent | 4 | Excellent | ||
| 7/34/M | UL | PA | + | Plegic | Hand + | Wave attenuation | Plegic | Hand ++ | <.0001 | Healthy side > painful side | 5 | Good: fMRI helped iCM targeting |
| 8/38/F | Face | TN | + | Normal | Hand +++ | Hand +++ | <.0001 | Similar extent | 6 | Excellent | ||
| Face 0 | No wave | No response | Face not studied | |||||||||
| 9/70/M | UL | SS | + | Paretic | Hand +++ | Hand +++ | <.0001 | Similar extent | 3 | Excellent | ||
| 10/65/F | UL | PRP | +++ | Plegic | Hand + | Wave attenuation | Plegic | Hand +++ | <.0001 | Similar extent | 3 | Good: fMRI helped iCM targeting |
| 11/50/F | Face | TN | + | Normal | Hand +++ | Hand +++ | <.0001 | Similar extent | 5 | Excellent | ||
| Face ++ | Diffused response | Face not studied | 5 | |||||||||
| 12/73/M | UL | A | +++ | None | Hand + | Wave attenuation | Amputation | Hand + | <.001 | Healthy side > painful side | 6 | Good: fMRI helped iCM targeting |
| 13/70/M | Face | TN | + | Normal | Hand +++ | Hand +++ | <.0001 | Similar extent | 3 | Excellent | ||
| Face 0 | Wave attenuation | Not studied | Face not studied | |||||||||
| 14/40/M | UL | A | +++ | None | Hand + | Wave attenuation | Amputation | Hand +++ | <.0001 | Similar extent | 3 | Good: fMRI helped iCM targeting |
| 15/54/F | LL | ScS | + | Paretic | Hand + | Wave attenuation | Hand ++ | <.0001 | Similar extent | 3 | Good: fMRI helped iCM targeting | |
| Foot 0 | No wave | Not studied | Foot ++ | <.0001 | Not studied | 5 | Good: fMRI helped iCM targeting | |||||
| 16/56/F | Face | TN | + | Normal | Hand +++ | Hand + | <.01 | Not studied | 4 | Good: low fMRI significance | ||
| Face ++ | Face not studied | |||||||||||
| 17/45/M | Face | TN | +++ | Normal | Hand +++ | Hand +++ | <.0001 | Similar extent | 3 | Excellent | ||
| Face 0 | No wave | Face ++ | <.0001 | Not studied | 5 | Good: fMRI helped iCM targeting | ||||||
| 18/66/F | UL | ScS | + | Normal | Hand +++ | Hand +++ | <.0001 | Similar extent | 1 | Excellent | ||
| Face | Face 0 | No wave | No response | Face ++ | <.001 | Not studied | ||||||
| 19/59/F | UL | ScS | ++ | Paretic | Hand +++ | Hand +++ | <.0001 | Similar extent | 3 | Excellent | ||
| Face | Face 0 | No wave | No resposne | Face 0 | <.001 | |||||||
| 20/43/M | UL | PA | ++ | Plegic | Hand + | Wave attenuation | Plegic | Hand +++ | <.0001 | Healthy side > painful side | 4 | Excellent |
| 21/72/M | UL | ScS | + | Paretic | Hand +++ | Artifacts | Hand +++ | <.0001 | Similar extent | 5 | Excellent | |
| LL | Foot + | Wave attenuation | No response | Foot ++ | <.0001 | Not studied | ||||||
Note.—iCM indicates intraoperative epidural cortical brain mapping; fMRI, functional magnetic resonance imaging; iSEP, intraoperative somatosensory-evoked potentials; iBS, intraoperative epidural motor cortex bipolar stimulodetection.
UL indicates upper limb; LL, lower limb; TN, trigeminal neuropathy; ScS, subcortical stroke; SS, spinal syrinx; PA, plexus avulsion; PRP, postradic plexopathy; A, amputation.
Quality scales for iCM and fMRI targeting are: 0, no significant target; +, fair and ambiguous target; ++, unambiguous target altered by artifacts/wave attenuation; +++, unambiguous and precise target.
P values correspond to the analysis threshold of fMRI activation areas. Values less than .001 correspond to the initial analysis threshold; some targets remained significant for values less than .00001.
Not studied indicates that comparisons between both sides were not studied because of alterations resulting from residual motion artifacts.
Distances reported between targets were measured intraoperatively by means of the neuronavigation microscope. They are purely indicative and do not reflect the resolution of fMRI and iCM.
Excellent/good indicate important/partial overlap between fMRI target or unambiguous/ambiguous iCM target (note that ambiguous iCM targets impede correlations for both targets at more restrictive P values).