Recursive grid partitioning on a cortical surface model: an optimized technique for the localization of implanted subdural electrodes

Pieters, Thomas A.; Conner, Christopher R.; Tandon, Nitin

doi:10.3171/2013.2.jns121450

Cited by 89 publications

(111 citation statements)

References 45 publications

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“…A three-dimensional surface image was finally created with the location of electrodes directly defined on the brain surface (Muzik et al, 2007; Alkonyi et al, 2009). We confirmed the spatial accuracy of electrode display on the three-dimensional brain surface image using intraoperative pictures (Wellmer et al, 2002; Dalal et al, 2008; Pieters et al, 2013). By the age of 5 years, brain size becomes comparable to that of an adult (Dekaban and Sadowsky, 1978), while the youngest patient in the present study was 9 year old.…”

Section: Methodssupporting

confidence: 65%

Upright face-preferential high-gamma responses in lower-order visual areas: Evidence from intracranial recordings in children

et al. 2015

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Behavioral studies demonstrate that a face presented in the upright orientation attracts attention more rapidly than an inverted face. Saccades toward an upright face take place in 100-140 ms following presentation. The present study using electrocorticography determined whether upright face-preferential neural activation, as reflected by augmentation of high-gamma activity at 80-150 Hz, involved the lower-order visual cortex within the first 100 ms post-stimulus presentation. Sampled lower-order visual areas were verified by the induction of phosphenes upon electrical stimulation. These areas resided in the lateral-occipital, lingual, and cuneus gyri along the calcarine sulcus, roughly corresponding to V1 and V2. Measurement of high-gamma augmentation during central (circular) and peripheral (annular) checkerboard reversal pattern stimulation indicated that central-field stimuli were processed by the more polar surface whereas peripheral-field stimuli by the more anterior medial surface. Upright face stimuli, compared to inverted ones, elicited up to 23% larger augmentation of high-gamma activity in the lower-order visual regions at 40-90 ms. Upright face-preferential high-gamma augmentation was more highly correlated with high-gamma augmentation for central than peripheral stimuli. Our observations are consistent with the hypothesis that lower-order visual regions, especially those for the central field, are involved in visual cues for rapid detection of upright face stimuli.

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Section: Methodssupporting

confidence: 65%

Upright face-preferential high-gamma responses in lower-order visual areas: Evidence from intracranial recordings in children

et al. 2015

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“…A three-dimensional MRI was created for each patient with the location of electrodes directly defined on the brain surface (Alkonyi et al, 2009; Matsuzaki et al, 2015). Using automatic parcellation of cortical gyri on FreeSurfer software (Desikan et al, 2006), subdural electrodes were assigned anatomical labels (Pieters et al, 2013; Matsuzaki et al, 2015; Supplementary Figure S2). …”

Section: Methodsmentioning

confidence: 99%

Spatial–temporal patterns of electrocorticographic spectral changes during midazolam sedation

Nishida

Zestos

Asano

2016

Clinical Neurophysiology

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Objective To better understand ‘when’ and ‘where’ wideband electrophysiological signals are altered by sedation. Methods We generated animation movies showing electrocorticography (ECoG) amplitudes at eight spectral frequency bands across 1.0 to 116 Hz, every 0.1 second, on three-dimensional surface images of 10 children who underwent epilepsy surgery. We measured the onset, intensity, and variance of each band amplitude change at given nonepileptic regions separately from those at affected regions. We also determined the presence of differential ECoG changes depending on the brain anatomy. Results Within 20 seconds following injection of midazolam, beta (16–31.5 Hz) and sigma (12–15.5 Hz) activities began to be multifocally augmented with increased variance in amplitude at each site. Beta-sigma augmentation was most prominent within the association neocortex. Augmentation of low-delta activity (1.0–1.5 Hz) was relatively modest and confined to the somatosensory-motor region. Conversely, injection of midazolam induced attenuation of theta (4.0–7.5 Hz) and high-gamma (64–116 Hz) activities. Conclusions Our observations support the notion that augmentation beta-sigma and delta activities reflects cortical deactivation or inactivation, whereas theta and high-gamma activities contribute to maintenance of consciousness. The effects of midazolam on the dynamics of cortical oscillations differed across regions. Significance Sedation, at least partially, reflects a multi-local phenomenon at the cortical level rather than global brain alteration homogeneously driven by the common central control structure.

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“…A photographic documentation of the electrode contact positions would have been preferable, as shown by Tao et al, 17 LaViolette et al, 18 and Pieters et al, 19 in cases in which a grid was implanted through a craniotomy. Dykstra et al 20 faced the same problem we do with localizing electrode contacts that are implanted through burr holes.…”

Section: Plausibility Of the Resultsmentioning

confidence: 99%

“…With grid implantation through craniotomy, the brain surface can be photographed and images can be superimposed onto a cortical MRI reconstruction. [15][16][17][18][19][20] Combinations of photography and 2-dimensional radiography have been described, 10 as have linear superpositions using a 3-dimensional visualization system. 9 Contacts under the margins of the craniotomy or placed through burr holes cannot be documented photographically; these contacts are also subject to brain shift, which can be corrected mathematically.…”

Section: Discussionmentioning

confidence: 99%

Improved Localization of Implanted Subdural Electrode Contacts on Magnetic Resonance Imaging With an Elastic Image Fusion Algorithm in an Invasive Electroencephalography Recording

Stieglitz

Ayer

Schindler³

et al. 2014

Operative Neurosurgery

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BACKGROUND: Accurate projection of implanted subdural electrode contacts in presurgical evaluation of pharmacoresistant epilepsy cases by invasive electroencephalography is highly relevant. Linear fusion of computed tomography and magnetic resonance images may display the contacts in the wrong position as a result of brain shift effects. OBJECTIVE: A retrospective study in 5 patients with pharmacoresistant epilepsy was performed to evaluate whether an elastic image fusion algorithm can provide a more accurate projection of the electrode contacts on the preimplantation magnetic resonance images compared with linear fusion. METHODS: An automated elastic image fusion algorithm (AEF), a guided elastic image fusion algorithm (GEF), and a standard linear fusion algorithm were used on preoperative magnetic resonance images and postimplantation computed tomography scans. Vertical correction of virtual contact positions, total virtual contact shift, corrections of midline shift, and brain shifts caused by pneumocephalus were measured. RESULTS: Both AEF and GEF worked well with all 5 cases. An average midline shift of 1.7 mm (SD, 1.25 mm) was corrected to 0.4 mm (SD, 0.8 mm) after AEF and to 0.0 mm (SD, 0 mm) after GEF. Median virtual distances between contacts and cortical surface were corrected by a significant amount, from 2.3 mm after linear fusion algorithm to 0.0 mm after AEF and GEF (P < .001). Mean total relative corrections of 3.1 mm (SD, 1.85 mm) after AEF and 3.0 mm (SD, 1.77 mm) after GEF were achieved. The tested version of GEF did not achieve a satisfying virtual correction of pneumocephalus. CONCLUSION: The technique provided a clear improvement in fusion of preimplantation and postimplantation scans, although the accuracy is difficult to evaluate. Improved Localization of Implanted Subdural Electrode Contacts on Magnetic Resonance Imaging With an Elastic Image Fusion Algorithm in an Invasive Electroencephalography RecordingBACKGROUND: Accurate projection of implanted subdural electrode contacts in presurgical evaluation of pharmacoresistant epilepsy cases by invasive electroencephalography is highly relevant. Linear fusion of computed tomography and magnetic resonance images may display the contacts in the wrong position as a result of brain shift effects. OBJECTIVE: A retrospective study in 5 patients with pharmacoresistant epilepsy was performed to evaluate whether an elastic image fusion algorithm can provide a more accurate projection of the electrode contacts on the preimplantation magnetic resonance images compared with linear fusion. METHODS: An automated elastic image fusion algorithm (AEF), a guided elastic image fusion algorithm (GEF), and a standard linear fusion algorithm were used on preoperative magnetic resonance images and postimplantation computed tomography scans. Vertical correction of virtual contact positions, total virtual contact shift, corrections of midline shift, and brain shifts caused by pneumocephalus were measured. RESULTS: Both AEF and GEF worked well with all 5 ca...

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Recursive grid partitioning on a cortical surface model: an optimized technique for the localization of implanted subdural electrodes

Cited by 89 publications

References 45 publications

Upright face-preferential high-gamma responses in lower-order visual areas: Evidence from intracranial recordings in children

Upright face-preferential high-gamma responses in lower-order visual areas: Evidence from intracranial recordings in children

Spatial–temporal patterns of electrocorticographic spectral changes during midazolam sedation

Improved Localization of Implanted Subdural Electrode Contacts on Magnetic Resonance Imaging With an Elastic Image Fusion Algorithm in an Invasive Electroencephalography Recording

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