Is intracranial electroencephalography useful for planning resective surgery in intractable epilepsy with ulegyria?

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OBJECTIVE

Intractable epilepsy patients with ulegyria could be candidates for resective surgery. Complete resection of ulegyria in the epileptogenic hemisphere is associated with favorable seizure outcome, although the risk of postoperative functional deficits is higher. The authors evaluated the extent of resection and postsurgical outcomes in epilepsy patients with ulegyria who underwent intracranial electroencephalography (iEEG) monitoring prior to resection to clarify the efficacy of iEEG-guided partial resection of ulegyria.

METHODS

Ten consecutive epilepsy patients with ulegyria (7 males and 3 females, age range at surgery 7–34 years) underwent iEEG prior to resective surgery between 2011 and 2017 with a minimum follow-up of 12 months (range 12–72 months). The diagnosis of ulegyria was based on the typical pattern of cortical atrophy especially at the bottom of the sulcus on MRI. An iEEG study was indicated after comprehensive preoperative evaluations, including high-field MRI, long-term video-EEG, magnetoencephalography, and FDG-PET. The resection planning was based on iEEG analysis. Total lesionectomy was not always performed, as preservation of cortical function was prioritized.

RESULTS

Ulegyria was seen in the occipital and/or parietal lobe in 9 patients and bilaterally in 5 patients. Ictal EEG onset involved the temporal neocortex in 6 patients. Intracranial electrodes were implanted unilaterally in all except 1 patient with bilateral lesions. The extent of MRI lesion was covered by the electrodes. Seizure onset zones (SOZs) and irritative zones (IZs) were identified in all patients. SOZs and IZs were completely resected in 8 patients but were only partially removed in the remaining 2 patients because the eloquent cortices and the epileptogenic zones overlapped. Ulegyria of the epileptogenic side was totally resected in 1 patient. Seizure freedom was achieved in 4 patients, including 3 after partial lesionectomy. Extended resection of the temporal neocortex was performed in 4 patients, although postoperative seizure freedom was achieved only in 1 of these patients. Visual field deficit was seen in 4 patients. Three of 5 patients with bilateral lesions achieved seizure freedom after unilateral resective surgery.

CONCLUSIONS

Intracranial EEG–guided partial lesionectomy provides a reasonable chance of postoperative seizure freedom with a lower risk of functional deficits. Patients with bilateral ulegyria should not be excluded from consideration as surgical candidates.

ABBREVIATIONS EEG = electroencephalography; IED = interictal epileptiform discharge; iEEG = intracranial EEG; ILAE = International League Against Epilepsy; IZ = irritative zone; MEG = magnetoencephalography; SOZ = seizure onset zone.
Article Information

Contributor Notes

Correspondence Masaki Iwasaki: National Center Hospital of Neurology and Psychiatry, Tokyo, Japan. iwa@ncnp.go.jp.INCLUDE WHEN CITING Published online October 25, 2019; DOI: 10.3171/2019.8.JNS191642.Disclosures The authors report no conflict of interest concerning the materials or methods used in this study or the findings specified in this paper.
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References
  • 1

    Bresler J: Klinische und pathologisch-anatomische Beiträge zur Mikrogyrie. Arch Psychiatr Nervenkr 31:5665731899

  • 2

    Gil-Nagel AGarcía Morales IJiménez Huete AAlvarez Linera Jdel Barrio ARuiz Ocaña C: Occipital lobe epilepsy secondary to ulegyria. J Neurol 252:117811852005

    • Search Google Scholar
    • Export Citation
  • 3

    Kuchukhidze GUnterberger IDobesberger JEmbacher NWalser GHaberlandt E: Electroclinical and imaging findings in ulegyria and epilepsy: a study on 25 patients. J Neurol Neurosurg Psychiatry 79:5475522008

    • Search Google Scholar
    • Export Citation
  • 4

    Marín-Padilla MParisi JEArmstrong DLSargent SKKaplan JA: Shaken infant syndrome: developmental neuropathology, progressive cortical dysplasia, and epilepsy. Acta Neuropathol 103:3213322002

    • Search Google Scholar
    • Export Citation
  • 5

    Norman MG: On the morphogenesis of ulegyria. Acta Neuropathol 53:3313321981

  • 6

    O’Connor ACostello DJ: Occipital ulegyria causing epilepsy and visual impairment: an easily overlooked epilepsy syndrome. Epileptic Disord 19:4864902017

    • Search Google Scholar
    • Export Citation
  • 7

    Schilling LPKieling RRPascoal TAKim HILee MCKim YH: Bilateral perisylvian ulegyria: an under-recognized, surgically remediable epileptic syndrome. Epilepsia 54:136013672013

    • Search Google Scholar
    • Export Citation
  • 8

    Usui NMihara TBaba KMatsuda KTottori TUmeoka S: Posterior cortex epilepsy secondary to ulegyria: is it a surgically remediable syndrome? Epilepsia 49:199820072008

    • Search Google Scholar
    • Export Citation
  • 9

    Villani FD’Incerti LGranata TBattaglia GVitali PChiapparini L: Epileptic and imaging findings in perinatal hypoxic-ischemic encephalopathy with ulegyria. Epilepsy Res 55:2352432003

    • Search Google Scholar
    • Export Citation
  • 10

    Wang FZheng HZhang XLi YGao ZWang Y: Successful surgery in lesional epilepsy secondary to posterior quandrant ulegyria coexisting with benign childhood focal epilepsy: a case report. Clin Neurol Neurosurg 149:94972016

    • Search Google Scholar
    • Export Citation
  • 11

    Wieser HGBlume WTFish DGoldensohn EHufnagel AKing D: ILAE Commission Report. Proposal for a new classification of outcome with respect to epileptic seizures following epilepsy surgery. Epilepsia 42:2822862001

    • Search Google Scholar
    • Export Citation
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