Innovative evaluation of visual field defects in epileptic patients after standard anterior temporal lobectomy, using partial field visual evoked potentials.
The purpose of this paper is to obtain an electrophysiological evaluation of visual field defects consecutive to the direct lesion of optic radiations in drug-resistant epileptic patients after a standard electrocorticographically adjusted lobectomy, and to correlate it with conventional perimetric results, and with the volume of resected tissue during surgical treatment. Twenty-four patients with temporal lobe epilepsy defined through long term EEG-video, ictal and interictal SPECT, as well as Magnetic Resonance Imaging were studied. Visual evoked potentials (VEPs) with partial and total visual field stimulation were carried out before and after 6, 12 and 24 months surgical treatment. A control group was also studied. No differences between patients and control subjects were observed during the evaluation of the full-field VEPs. However, there were statistical differences between groups in the half-field VEP recordings and in the VEP recordings of contralateral to resected side superior quadrant (CSQ) before lobectomy and 6 months later (Mann-Whitney's U-test, p<0.05). Significant associations were found between VEP abnormalities and perimetric results in CSQ. A close relationship between perimetry, VEPs and volume of the resected tissue in hippocampus, parahippocampus, medial and lower temporal giri was also found. Visual field defects consecutive to standard temporal lobe resection in epileptic patients could be objectively evaluated by partial stimulation VEPs corresponding to the size of resected tissue.
Báez Martín
Margarita Minou
MM
International Center for Neurological Restoration (CIREN) Havana, Cuba. minou@infomed.sld.cu
del Carmen Pérez Téllez
Yamila
Y
Chacón
Lilia María Morales
LM
Díaz
Bárbara Estupiñán
BE
Trápaga-Quincoses
Otto
O
Maeso
Iván García
IG
Bender
Juan E
JE
Galvizu
Reynaldo
R
García
María Eugenia
ME
Abreu
Ivette Cabrera
IC
Rodríguez
Gladys Soto
GS
D000328:Adult; D038481:Anterior Temporal Lobectomy / Q000009:adverse effects*; D019781:Corneal Topography / Q000379:methods; D004569:Electroencephalography / Q000379:methods; D004833:Epilepsy, Temporal Lobe / Q000473:pathology / Q000601:surgery; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005260:Female; D005500:Follow-Up Studies; D007839:Functional Laterality; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009778:Occipital Lobe / Q000503:physiopathology*; D010775:Photic Stimulation / Q000379:methods; D011930:Reaction Time / Q000502:physiology; D018709:Statistics, Nonparametric; D014786:Vision Disorders / Q000175:diagnosis* / Q000209:etiology*; D058609:Visual Field Tests / Q000379:methods; D014794:Visual Fields / Q000502:physiology*; D055815:Young Adult