Characterizing the relationship between functional MRI-derived measures and clinical outcomes in patients with vascular lesions.
ABSTRACT Object Functional MRI (fMRI) has proven to be an effective component of pretreatment planning in patients harboring a variety of different brain lesions. The authors have recently reported significant relationships concerning distances between brain tumor borders and areas of functional activation (lesion-to-activation distance; LAD) with regard to patient morbidity and mortality. This study further examines the relationship between LAD, focusing on a host of vascular lesions and pre- and posttreatment morbidity. Methods This study included a sample population of patients with vascular lesions (n = 106), primarily arteriovenous malformations (AVMs) and cavernomas. These patients underwent pretreatment fMRI-based motor mapping (n = 72) or language mapping (n = 84). The impact of LAD and other variables derived from the patient medical record were analyzed with respect to functional deficits in terms of morbidity (weakness and/or aphasia). Results In patients with no pretreatment deficits, there was trend for a significant relationship between the Wernicke area LAD and posttreatment language deficits. In patients with or without pretreatment deficits, a trend toward significance was observed between sensorimotor LAD and posttreatment motor deficits. Additionally, lesion type (AVMs or cavernomas) affected posttreatment deficits, with more patients with cavernomas showing posttreatment language deficits than patients with AVMs. However, this difference was not observed for posttreatment motor deficits. Conclusions These findings suggest that the proximity of a vascular lesion to sensorimotor and language areas is a relevant parameter in estimating patient prognosis in the perioperative period. Additionally, vascular lesion type and existence of pretreatment deficits play a significant role in outcomes.
- [Show abstract] [Hide abstract]
ABSTRACT: BOLD fMRI has, during the past decade, made a major transition from a purely research imaging technique to a viable clinical technique used primarily for presurgical planning in patients with brain tumors and other resectable brain lesions. This review article briefly examines the history and evolution of clinical functional imaging, with particular emphasis on how the use of BOLD fMRI for neurosurgical planning has changed during the past 2 decades. Even more important, this article describes the many published studies during that same period that have examined the overall clinical impact that BOLD and DTI have made on surgical planning.American Journal of Neuroradiology 02/2010; 31(2):219-25. DOI:10.3174/ajnr.A1845 · 3.68 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: fMRI is increasingly used in neurosurgery to preoperatively identify areas of eloquent cortex. Our study evaluated the efficacy of clinical fMRI by analyzing the relationship between the distance from the tumor border to the area of functional activation (LAD) and patient pre- and postoperative morbidity and mortality. The study included patients with diagnosis of primary or metastatic brain tumor who underwent preoperative fMRI-based motor mapping (n=74) and/or language mapping (n=77). The impact of LAD and other variables collected from patient records was analyzed with respect to functional deficits in terms of morbidity (paresis and aphasia) and mortality. Significant relationships were found between motor and language LAD and the existence of either pre- or postoperative motor (P < .001) and language deficits (P=.009). Increasing age was associated with motor and language deficits (P=.02 and P=.04 respectively). Right-handedness was related to language deficits (P=.05). Survival analysis revealed that pre- and postoperative deficits, grade, tumor location, and LAD predicted mortality. Motor deficits increased linearly as the distance from the tumor to the primary sensorimotor cortex decreased. Language deficits increased exponentially as the distance from the tumor to the language areas decreased below 1 cm. Postoperative mortality analysis showed an interaction effect between motor or language LAD and mortality predictors (grade and tumor location, respectively). These findings indicate that tumors may affect language and motor function differently depending on tumor LAD. Overall, the data support the use of fMRI as a tool to evaluate patient prognosis and are directly applicable to neurosurgical planning.American Journal of Neuroradiology 09/2011; 32(8):1420-5. DOI:10.3174/ajnr.A2679 · 3.68 Impact Factor
- [Show abstract] [Hide abstract]
ABSTRACT: In 90% of normal subjects, the left hemisphere is dominant for language function. We investigated whether congenital lesions of the left perisylvian regions altered cortical language representation in right-handed individuals. Using functional magnetic resonance imaging, we studied language hemispheric dominance in five right-handed adult patients with congenitally acquired arteriovenous malformations (AVMs) originating from left hemispheric cortical language regions. The AVMs had not caused neurological symptoms during early development, but patients presented as adults with migraine, seizure, or minor hemorrhage. Results obtained from the AVM patients were contrasted to those from right-handed brain-injured stroke patients recovering from aphasia and to those from right-handed normal subjects. During silent picture naming and verb generation tasks, cortical language networks lateralized primarily to the right hemisphere in the AVM group, compared with the left hemisphere in the normal group. This right hemisphere-shifted language network in the AVM group exceeded the shifts toward right hemispheric dominance found in the stroke group. Patients with AVMs affecting the left perisylvian regions recruited the right hemisphere into language processing networks during early development, presumably in response to congenitally aberrant circulation. This early right hemisphere recruitment in the AVM patients exceeded the similar process in the brains of stroke patients whose left cortical language networks were damaged in adulthood. Our data provide evidence of effective plasticity in the developing human brain compared with the mature brain response to injury. Knowledge of cortical language representation should assist presurgical planning in patients with developmental anomalies affecting apparently language-dominant brain regions.Neurosurgery 10/2000; 47(3):562-70. DOI:10.1097/00006123-200009000-00004 · 3.03 Impact Factor