Lesion-induced Pseudo-dominance at Functional Magnetic Resonance Imaging: Implications for Preoperative Assessments

Ulmer, John L.; Hacein‐Bey, Lotfi; Mathews, Vincent P.; Mueller, Wade; DeYoe, Edgar A.; Prost, Robert; Meyer, Glenn A.; Krouwer, Hendrikus G. J.; Schmainda, Kathleen M.

doi:10.1227/01.neu.0000134384.94749.b2

Cited by 188 publications

(96 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Ulmer et al proposed that lesion-induced neurovascular uncoupling causing reduced fMRI signal in perilesional eloquent cortex may simulate lesion-induced cortical reorganization. 31 On the other hand, in a more recent study, functional brain mapping using navigated transcranial magnetic stimulation showed that no plastic relocation of the primary motor cortex was observed in the 6 patients with AVMs near the rolandic region, even if the anatomy was severely obscured by the rolandic AVM. 21 Therefore, it seems that cortical reorganization on fMRI is not a significant predictor of surgical outcomes.…”

Section: Discussionmentioning

confidence: 94%

“…1) Pathophysiological factors, including gliosis, hemosiderosis, neovascularity, and AVM-induced hemodynamic effects, may cause neurovascular uncoupling and reduce fMRI signal in perilesional eloquent cortex. 31 2) Observational methods such as fMRI do not prove necessity or sufficiency of a particular area for function; instead, fMRI is only able to demonstrate a particular area's involvement in motor function. 1 3) White matter involvement could be contributing to and confounding the relationship.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Risk factors for worsened muscle strength after the surgical treatment of arteriovenous malformations of the eloquent motor area

Lin

Zhao

et al. 2016

JNS

View full text Add to dashboard Cite

abbreviatioNs AUC = area under the ROC curve; AVM = arteriovenous malformation; BOLD = blood oxygen level-dependent; CST = corticospinal tract; DSA = digital subtraction angiography; DTI = diffusion tensor imaging; DW = diffusion weighted; EPI = echo-planar imaging; FA = fractional anisotropy; FAPA = feeding artery from perforating artery; fMRI = functional MRI; LAD = lesion-to-activation area distance; LCD = lesion-to-CST distance; MS = preoperative muscle strength; MS 1 = muscle strength 1 week postoperatively; MS 2 = muscle strength 6 months postoperatively; NPPB = normal perfusion pressure breakthrough; ROC = receiver operating characteristic; ROI = region of interest; SM = Spetzler-Martin; TOF = time-of-flight. obJective Case selection for the surgical treatment of arteriovenous malformations (AVMs) of the eloquent motor area remains challenging. The aim of this study was to determine the risk factors for worsened muscle strength after surgery in patients with this disorder. methods At their hospital the authors retrospectively studied 48 consecutive patients with AVMs involving motor cortex and/or the descending pathway. All patients had undergone preoperative functional MRI (fMRI) and diffusion tensor imaging (DTI), followed by resection. Both functional and angioarchitectural factors were analyzed with respect to the change in muscle strength. Functional factors included lesion-to-corticospinal tract distance (LCD) on DTI and lesion-toactivation area distance (LAD) and cortical reorganization on fMRI. Based on preoperative muscle strength, the changes in muscle strength at 1 week and 6 months after surgery were defined as short-term and long-term surgical outcomes, respectively. Statistical analysis was performed using the statistical package SPSS (version 20.0.0, IBM Corp.). results Twenty-one patients (43.8%) had worsened muscle strength 1 week after surgery. However, only 10 patients (20.8%) suffered from muscle strength worsening 6 months after surgery. The LCD was significantly correlated with short-term (p < 0.001) and long-term (p < 0.001) surgical outcomes. For long-term outcomes, patients in the 5 mm ≥ LCD > 0 mm (p = 0.009) and LCD > 5 mm (p < 0.001) categories were significantly associated with a lower risk of permanent motor worsening in comparison with patients in the LCD = 0 mm group. No significant difference was found between patients in the 5 mm ≥ LCD > 0 mm group and LCD > 5 mm group (p = 0.116). Nidus size was the other significant predictor of short-term (p = 0.021) and long-term (p = 0.016) outcomes. For long-term outcomes, the area under the ROC curve (AUC) was 0.728, and the cutoff point was 3.6 cm. Spetzler-Martin grade was not associated with short-term surgical outcomes (0.143), although it was correlated with long-term outcomes (0.038). coNclusioNs An AVM with a nidus in contact with tracked eloquent fibers (LCD = 0) and having a large size is more likely to be associated with worsened muscle strength after surgery in patients with eloquent motor area AVMs. Surgical treatment i...

show abstract

Section: Discussionmentioning

confidence: 94%

Section: Discussionmentioning

confidence: 99%

Risk factors for worsened muscle strength after the surgical treatment of arteriovenous malformations of the eloquent motor area

Lin

Zhao

et al. 2016

JNS

View full text Add to dashboard Cite

show abstract

“…Tumors and congenital lesions may cause neurovascular coupling, compromising the blood oxygen level-dependent functional MR imaging signal in the regional eloquent cortex (2,5,(41)(42)(43). The area of motor cortex activation is influenced by the rate and force of contractions (44)(45)(46)(47)(48)(49)(50)(51).…”

Section: Figurementioning

confidence: 99%

“…This approach correlates well with intraoperative mapping (11) and the risk of motor postoperative deficits (4), and it can be used in conjunction with intraoperative localization techniques (12). Functional MR imaging is complementary to, although not a replacement for, these other methods of localization, including intraoperative electrocortical stimulation (2,5). Intraoperative electrocortical mapping also has limitations, however, particularly when the motor cortex is located deep within a sulcus and is not accessible to surface stimulation (13).…”

mentioning

confidence: 96%

See 1 more Smart Citation

Motor Homunculus: Passive Mapping in Healthy Volunteers by Using Functional MR Imaging—Initial Results

Koçak

Ulmer

Uğurel³

et al. 2009

Radiology

Self Cite

View full text Add to dashboard Cite

Purpose:To determine the concurrence of activation in the primary motor cortex, induced by paradigms of active and passive movement of extremities, by using blood oxygen leveldependent functional magnetic resonance (MR) imaging. Materials and Methods:The HIPAA-compliant study was approved by the institutional review board, and written informed consent was obtained from the participating volunteers. Functional MR imaging data were collected from 11 healthy volunteers (four women, seven men; age range, 24 -42 years) during active and passive movements of hand, elbow, shoulder, ankle, knee, and hip. These data were then mapped onto three-dimensional anatomic images. Volumes of activation were determined by using cross-correlation analysis at a coefficient threshold of 0.4 (P Ͻ .01). Regions of interest were drawn in pre-and postcentral gyri based on anatomic criteria. The mean number of activated voxels in the preand postcentral gyri induced by active and passive movements was compared by using Wilcoxon analysis. Concurrence ratios and proportional ratios of activation between active and passive movements were calculated for each somatotopic location.

show abstract

Regional and hemispheric determinants of language laterality: Implications for preoperative fMRI

Seghier

Kherif

Josse

et al. 2010

Human Brain Mapping

View full text Add to dashboard Cite

Language is typically a function of the left hemisphere but the right hemisphere is also essential in some healthy individuals and patients. This inter-subject variability necessitates the localization of language function, at the individual level, prior to neurosurgical intervention. Such assessments are typically made by comparing left and right hemisphere language function to determine ''language lateralization'' using clinical tests or fMRI. Here, we show that language function needs to be assessed at the region and hemisphere specific level, because laterality measures can be misleading. Using fMRI data from 82 healthy participants, we investigated the degree to which activation for a semantic word matching task was lateralized in 50 different brain regions and across the entire cortex. This revealed two novel findings. First, the degree to which language is lateralized across brain regions and between subjects was primarily driven by differences in right hemisphere activation rather than differences in left hemisphere activation. Second, we found that healthy subjects who have relatively high left lateralization in the angular gyrus also have relatively low left lateralization in the ventral precentral gyrus. These findings illustrate spatial heterogeneity in language lateralization that is lost when global laterality measures are considered. It is likely that the complex spatial variability we observed in healthy controls is more exaggerated in patients with brain damage. We therefore highlight the importance of investigating within hemisphere regional variations in fMRI activation, prior to neuro-surgical intervention, to determine how each hemisphere and each region contributes to language processing. Hum Brain Mapp 32:1602-1614,

show abstract

Lesion-induced Pseudo-dominance at Functional Magnetic Resonance Imaging: Implications for Preoperative Assessments

Abstract: Lesion-induced neurovascular uncoupling causing reduced fMRI signal in perilesional eloquent cortex, in conjunction with normal or increased activity in homologous brain regions, may simulate hemispheric dominance and lesion-induced homotopic cortical reorganization.

Cited by 188 publications

References 37 publications

Risk factors for worsened muscle strength after the surgical treatment of arteriovenous malformations of the eloquent motor area

Risk factors for worsened muscle strength after the surgical treatment of arteriovenous malformations of the eloquent motor area

Motor Homunculus: Passive Mapping in Healthy Volunteers by Using Functional MR Imaging—Initial Results

Regional and hemispheric determinants of language laterality: Implications for preoperative fMRI

Contact Info

Product

Resources

About