BACKGROUND AND PURPOSE: Blood oxygen level-dependent functional MR imaging (BOLD fMRI) is a clinically useful technique for preoperative mapping of eloquent cortices in patients with brain tumors. The purpose of this study was to determine the effect on BOLD fMRI accuracy of susceptibility artifacts caused by prior surgery by comparing volumes of activation in the primary motor cortex (PMC) of patients with and without prior brain surgery. METHODS: The volumes of fMRI activation of the PMC were measured for the tumor and nontumor sides in patients with (n = 13) and without (n = 30) prior neurosurgery. Statistical comparisons of the volumes were performed by using paired t tests and linear regression analysis. The location and degree of susceptibility artifact were subjectively assessed. RESULTS: No significant difference was found between the mean tumor and nontumor volumes of fMRI activations in patients without prior surgery (P = .51). In patients who had prior surgery, the volume of activation was significantly smaller on the side of the prior operation when compared with the contralateral side (P = .001). The volume of activation on the side of the tumor was also significantly smaller in the patients with prior surgery compared with those without prior surgery (P < .001). Nevertheless, the PMC was identified in all cases, and its location was confirmed intraoperatively. CONCLUSION: Prior surgery is associated with a decrease in the volume of fMRI activation in patients with prior surgery; however, by examining the T2 images, an astute radiologist can recognize this phenomenon, draw the appropriate conclusions, and correctly identify the PMC.
BACKGROUND AND PURPOSE: Blood oxygen level-dependent functional MR imaging (BOLD fMRI) is a clinically useful technique for preoperative mapping of eloquent cortices in patients with brain tumors. The purpose of this study was to determine the effect on BOLD fMRI accuracy of susceptibility artifacts caused by prior surgery by comparing volumes of activation in the primary motor cortex (PMC) of patients with and without prior brain surgery. METHODS: The volumes of fMRI activation of the PMC were measured for the tumor and nontumor sides in patients with (n = 13) and without (n = 30) prior neurosurgery. Statistical comparisons of the volumes were performed by using paired t tests and linear regression analysis. The location and degree of susceptibility artifact were subjectively assessed. RESULTS: No significant difference was found between the mean tumor and nontumor volumes of fMRI activations in patients without prior surgery (P = .51). In patients who had prior surgery, the volume of activation was significantly smaller on the side of the prior operation when compared with the contralateral side (P = .001). The volume of activation on the side of the tumor was also significantly smaller in the patients with prior surgery compared with those without prior surgery (P < .001). Nevertheless, the PMC was identified in all cases, and its location was confirmed intraoperatively. CONCLUSION: Prior surgery is associated with a decrease in the volume of fMRI activation in patients with prior surgery; however, by examining the T2 images, an astute radiologist can recognize this phenomenon, draw the appropriate conclusions, and correctly identify the PMC.
Authors: J D McDonald; B W Chong; J D Lewine; G Jones; R B Burr; P R McDonald; S B Koehler; J Tsuruda; W W Orrison; M P Heilbrun Journal: J Neurosurg Date: 1999-03 Impact factor: 5.115
Authors: J A Maldjian; M Schulder; W C Liu; I K Mun; D Hirschorn; R Murthy; P Carmel; A Kalnin Journal: J Comput Assist Tomogr Date: 1997 Nov-Dec Impact factor: 1.826
Authors: J W Belliveau; B R Rosen; H L Kantor; R R Rzedzian; D N Kennedy; R C McKinstry; J M Vevea; M S Cohen; I L Pykett; T J Brady Journal: Magn Reson Med Date: 1990-06 Impact factor: 4.668
Authors: A A Desai; M K Strother; C C Faraco; V L Morgan; T R Ladner; L M Dethrage; L C Jordan; M J Donahue Journal: AJNR Am J Neuroradiol Date: 2015-08-13 Impact factor: 3.825
Authors: Mohammad Fakhri; Mohammad Ali Oghabian; Faeze Vedaei; Ali Zandieh; Nina Masoom; Guive Sharifi; Mohammad Ghodsi; Kavous Firouznia Journal: Funct Neurol Date: 2013 Jan-Mar
Authors: I M Ruff; N M Petrovich Brennan; K K Peck; B L Hou; V Tabar; C W Brennan; A I Holodny Journal: AJNR Am J Neuroradiol Date: 2008-01-09 Impact factor: 3.825
Authors: Ryan A Fisicaro; Ethan Jost; Katharina Shaw; Nicole Petrovich Brennan; Kyung K Peck; Andrei I Holodny Journal: Top Magn Reson Imaging Date: 2016-02