I have read with great interest the article by Bartolini et al1 that appears in the previous issue of this journal.
The authors highlight the high sensitivity of 7T T2*-weighted MR imaging in the identification and anatomic delimitation of cortical focal dysplasia (CFD) type IIb, specifying that this study will help more precise surgical planning, as well as explain the cases of failure in epilepsy operations. While it is true that 7T MR imaging has these advantages, it is also true that not all centers where epilepsy surgery is performed have the possibility of having such a team.
Probably more affordable is the availability of a neuronavigation team that could achieve quite similar results.2
I present the case of a 3-year-old boy with a history of intellectual disability and 12–16 simple partial motor daily seizures secondarily generalized from 3 months of age despite different schemes of antiepileptic polytherapy, in which an extensive and diffuse right parieto-occipital cortico-subcortical lesion was diagnosed, congruent with the site of the onset of epileptogenic discharges.
With neuronavigator and neurophysiologic monitoring with a subdural grid electrode of 32 contacts placed over the lesion and 2 interhemispheric strip electrodes of 4 contacts, the anatomo-functional margins of the lesion could be identified with high precision, and by means of a right parietal quadrantectomy with disconnection of the splenium, the entire lesion was resected (Figure).
Pathology confirmed CFD type IIb. At 18 months after the operation, the patient remained free of seizures (Engel I), with a sequential homonymous left hemianopia.
Neuronavigation proved to be an instrument of remarkable utility in the identification, delimitation, and complete resection of this voluminous cortical dysplasia. The advantage of the neuronavigation is that it allows a volumetric location of the lesion, which increases the accuracy of the resection of the lesion.
References
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