Intraoperative Ultrasound in Malformations of Cortical Development

Zusammenfassung

Ziel: Kortikale Malformationen (MCD) sind eine häufige Ursache medikamentenrefraktärer fokaler Epilepsien. Intraoperativ lassen sich MCD häufig schwierig vom normalen Hirngewebe abgrenzen. In dieser Studie untersuchen wir die Anwendbarkeit von intraoperativem Ultraschall (IOUS) zur Lokalisierung und Abgrenzung von MCD. Material und Methoden: Fünf Epilepsiepatienten mit mindestens einer MCD-verdächtigen Läsion wurden unter Anwendung von IOUS operiert. Die Ergebnisse des IOUS wurden mit dem präoperativen MRT und der Histopathologie verglichen. Ergebnisse: In drei Fällen fokaler kortikaler Dysplasie (FCD) Typ IIB und einem Fall periventrikulärer Heterotopien konnten die Läsionen gut im IOUS dargestellt werden, die Konfiguration der Läsionen im IOUS entsprach deren Aussehen im MRT. Dagegen konnte nur eine von zwei FCD Typ I im IOUS dargestellt werden. Schlussfolgerung: IOUS kann zur intraoperativen Darstellung von FCD IIB und periventrikulären Heterotopien hilfreich sein, die Darstellbarkeit von FCD Typ I scheint jedoch schwieriger zu sein.

Abstract

Purpose: Malformations of cortical development (MCD) are a common cause of medically refractory focal epilepsy. However, the intraoperative definition of MCD can be challenging. In this study we assess the feasibility of intraoperative ultrasound (IOUS) for the intraoperative localization of MCD. Materials and Methods: Five epilepsy patients with at least one suspected lesion of MCD were operated with the aid of IOUS. IOUS was compared to preoperative MRI and histopathology. Results: In three cases of focal cortical dysplasia (FCD) type IIB and one case of periventricular heterotopia, the lesions could be delineated well on IOUS and the configuration of the lesion corresponded to the appearance on MRI. However, only one of two FCD type I lesions could be detected on IOUS. Conclusion: IOUS can be helpful in defining FCD IIB as well as periventricular heterotopia intraoperatively, but this seems to be more difficult in FCD type I.

intraoperative ultrasound - epilepsy - seizures - ultrasound 2D - dysplasia

References

• 1 Forsgren L, Beghi E, Oun A et al. The epidemiology of epilepsy in Europe – a systematic review.  Eur J Neurol. 2005;  12 245-253
• 2 Kuzniecky R, Murro A, King D et al. Magnetic resonance imaging in childhood intractable partial epilepsies: pathologic correlations.  Neurology. 1993;  43 681-687
• 3 Palmini A, Najm I, Avanzini G et al. Terminology and classification of the cortical dysplasias.  Neurology. 2004;  62 S2-S8
• 4 Tassi L, Colombo N, Garbelli R et al. Focal cortical dysplasia: neuropathological subtypes, EEG, neuroimaging and surgical outcome.  Brain. 2002;  125 1719-1732
• 5 Knake S, Triantafyllou C, Wald L L et al. 3 T phased array MRI improves the presurgical evaluation in focal epilepsies: a prospective study.  Neurology. 2005;  65 1026-1031
• 6 Colombo N, Salamon N, Raybaud C et al. Imaging of malformations of cortical development.  Epileptic Disord. 2009;  11 194-205
• 7 Krsek P, Pieper T, Karlmeier A et al. Different presurgical characteristics and seizure outcomes in children with focal cortical dysplasia type I or II.  Epilepsia. 2009;  50 125-137
• 8 Huppertz H J, Grimm C, Fauser S et al. Enhanced visualization of blurred gray-white matter junctions in focal cortical dysplasia by voxel-based 3D MRI analysis.  Epilepsy Res. 2005;  67 35-50
• 9 Miller D, Knake S, Bauer S et al. Intraoperative ultrasound to define focal cortical dysplasia in epilepsy surgery.  Epilepsia. 2008;  49 156-158
• 10 Enchev Y, Bozinov O, Miller D et al. Image-guided ultrasonography for recurrent cystic gliomas.  Acta Neurochir. 2006;  148 1053-1063
• 11 Gronningsaeter A, Kleven A, Ommedal S et al. SonoWand, an ultrasound-based neuronavigation system.  Neurosurgery. 2000;  47 1373-1379 ; discussion 1379 – 1380
• 12 Engel J, Van Ness P C, Rasmussen T B. et al .Outcome with respect to epileptic seizures. In: Engel J, ed, Surgical treatment of the epilepsies.. New York: Raven Press; 1993: 609-621
• 13 Fauser S, Schulze-Bonhage A, Honegger J et al. Focal cortical dysplasias: surgical outcome in 67 patients in relation to histological subtypes and dual pathology.  Brain. 2004;  127 2406-2418
• 14 Bast T, Ramantani G, Seitz A et al. Focal cortical dysplasia: prevalence, clinical presentation and epilepsy in children and adults.  Acta Neurol Scand. 2006;  113 72-81
• 15 Cohen-Gadol A A, Ozduman K, Bronen R A et al. Long-term outcome after epilepsy surgery for focal cortical dysplasia.  J Neurosurg. 2004;  101 55-65
• 16 Luders H, Awad I, Burgess R et al. Subdural electrodes in the presurgical evaluation for surgery of epilepsy.  Epilepsy Res Suppl. 1992;  5 147-156
• 17 Chamoun R B, Nayar V V, Yoshor D. Neuronavigation applied to epilepsy monitoring with subdural electrodes.  Neurosurg Focus. 2008;  25 E21
• 18 Jea A, Vachhrajani S, Johnson K K et al. Corpus callosotomy in children with intractable epilepsy using frameless stereotactic neuronavigation: 12-year experience at the Hospital for Sick Children in Toronto.  Neurosurg Focus. 2008;  25 E7
• 19 Stone S S, Rutka J T. Utility of neuronavigation and neuromonitoring in epilepsy surgery.  Neurosurg Focus. 2008;  25 E17
• 20 Wurm G, Ringler H, Knogler F et al. Evaluation of neuronavigation in lesional and non-lesional epilepsy surgery.  Comput Aided Surg. 2003;  8 204-214
• 21 Dorward N L, Alberti O, Velani B et al. Postimaging brain distortion: magnitude, correlates, and impact on neuronavigation.  J Neurosurg. 1998;  88 656-662
• 22 Albert G W, Dahdaleh N S, Reddy C et al. Postoperative radiographic findings in patients undergoing intracranial electrode monitoring for medically refractory epilepsy.  J Neurosurg. 2010;  112 449-454
• 23 Buchfelder M, Fahlbusch R, Ganslandt O et al. Use of intraoperative magnetic resonance imaging in tailored temporal lobe surgeries for epilepsy.  Epilepsia. 2002;  43 864-873
• 24 Schwartz T H, Marks D, Pak J et al. Standardization of amygdalohippocampectomy with intraoperative magnetic resonance imaging: preliminary experience.  Epilepsia. 2002;  43 430-436
• 25 Walker D G, Talos F, Bromfield E B et al. Intraoperative magnetic resonance for the surgical treatment of lesions producing seizures.  J Clin Neurosci. 2002;  9 515-520
• 26 Mittal S, Black P M. Intraoperative magnetic resonance imaging in neurosurgery: the Brigham concept.  Acta Neurochir Suppl. 2006;  98 77-86
• 27 Abdel Razek A A, Kandell A Y, Elsorogy L G et al. Disorders of cortical formation: MR imaging features.  Am J Neuroradiol. 2009;  30 4-11