Predicting posttraumatic epilepsy with MRI: prospective longitudinal morphologic study in adults.
OBJECTIVE
Evaluation of morphologic risk factors for posttraumatic epilepsy (PTE) by using brain magnetic resonance imaging (MRI) in serial assessments <or=2 years after traumatic brain injury (TBI).


METHODS
Brain MRI hyperintense (gliosis) or hypointense (hemosiderin) areas or both were assessed in the images of 135 adult TBI inpatients who completed a 2-year clinical, EEG, and MRI study protocol. Overall clinical follow-up for the development of PTE was 5-10 years (median, 102 months). Morphologic risk factors for PTE were evaluated by using Kaplan-Meier curves and Cox regression analysis.


RESULTS
In 20 patients, PTE developed. Kaplan-Meier curves showed that gliomesenchymal sequelae of focal brain lesions (subdural hematomas/contusions) that required surgical treatment (sSDH-C) were a PTE risk factor (p<0.001), as were sequelae of nonsurgical hemorrhagic contusions with gliosis wall incompletely surrounding hemosiderin dregs (IW) (p=0.039) and mainly those with time-related changes from incomplete to complete gliosis wall around hemosiderin (I/CW) (p=0.005); those with early hemosiderin completely surrounded by gliosis (CW) were not (p=0.821). Cox regression analysis showed that for patients with sequelae of sSDH-C, the PTE risk was 4.38 (p=0.023) times higher than for those who did not require surgical treatment or underwent surgery because of purely extradural hematoma; for those with IW and I/CW lesions, considered pooled, it was 6.61 times higher (p=0.014) than for those with CW lesions.


CONCLUSIONS
MRI follow-up examination in the early chronic stage can differentiate among low-, intermediate-, and high-risk sequelae of TBI. These findings yield new evidence for, but do not resolve, the debate on posttraumatic epileptogenesis.
Messori
Anna
A
Department of Neuroradiology, Umberto I Hospital and University of Ancona, Ancona, Italy.
Polonara
Gabriele
G
Carle
Flavia
F
Gesuita
Rosaria
R
Salvolini
Ugo
U
D000328:Adult; D001927:Brain Diseases / Q000473:pathology; D001930:Brain Injuries / Q000175:diagnosis / Q000473:pathology*; D004569:Electroencephalography; D004834:Epilepsy, Post-Traumatic / Q000473:pathology*; D005260:Female; D005500:Follow-Up Studies; D005911:Gliosis / Q000473:pathology; D006486:Hemosiderosis / Q000473:pathology; D006801:Humans; D008137:Longitudinal Studies; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D011446:Prospective Studies; D012307:Risk Factors; D015599:Trauma Severity Indices