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Yawara Eguchi - One of the best experts on this subject based on the ideXlab platform.
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does the increased motion probing gradient directional diffusion tensor imaging of Lumbar Nerves using multi band sense improve the visualization and accuracy of fa values
European Spine Journal, 2020Co-Authors: Masaki Norimoto, Yawara Eguchi, Sumihisa Orita, Atsuya Watanabe, Takayuki Sakai, Daichi Murayama, Masami Yoneyama, Yohei Kawasaki, Takeo Furuya, Kazuhide InageAbstract:Diffusion tensor imaging (DTI) is useful to evaluate Lumbar Nerves visually and quantitatively. Multi-band sensitivity encoding (MB-SENSE) is a technique to reduce the scan time. This study aimed to investigate if super-multi-gradient DTI with multi-band sensitivity encoding (MB-SENSE) is better in evaluating Lumbar Nerves than the conventional method. The participants were 12 healthy volunteers (mean age 33.6 years). In all subjects, DTI was performed using echo planar imaging with different motion probing gradient (MPG) directions (15 without MB, and 15, 32, 64, and 128 with MB) and the Lumbar nerve roots were visualized with tractography. In the five groups, we evaluated the resultant DTI both visually and quantitatively. For visual measures, we counted the number of fluffs and disruptions of the nerve fibers. For quantitative measures, the fractional anisotropy (FA) and standard deviation of the fractional anisotropy (FA-SD) values at two regions (proximal and distal) of the Lumbar nerve roots were quantified and compared. Among the five groups, the number of fluffs decreased as the number of MPG directions increased. However, the number of disruptions showed no significant differences. The FA-SD values decreased as the number of MPG directions increased, indicating that the signal variation was reduced with multi-gradient directional DTI. High-resolution multi-directional DTI with MB-SENSE may be useful to visualize nerve entrapments and may allow for more accurate DTI parameter quantification with opportunities for clinical diagnostic applications.
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Diffusion tensor tractography of the Lumbar Nerves before a direct lateral transpsoas approach to treat degenerative Lumbar scoliosis
Journal of Neurosurgery, 2019Co-Authors: Yawara Eguchi, Masaki Norimoto, Munetaka Suzuki, Ryota Haga, Hajime Yamanaka, Hiroshi Tamai, Tatsuya Kobayashi, Sumihisa Orita, Miyako Suzuki, Kazuhide InageAbstract:OBJECTIVEThe purpose of this study was to determine the relationship between vertebral bodies, psoas major morphology, and the course of Lumbar nerve tracts using diffusion tensor imaging (DTI) before lateral interbody fusion (LIF) to treat spinal deformities.METHODSDTI findings in a group of 12 patients (all women, mean age 74.3 years) with degenerative Lumbar scoliosis (DLS) were compared with those obtained in a matched control group of 10 patients (all women, mean age 69.8 years) with low-back pain but without scoliosis. A T2-weighted sagittal view was fused to tractography from L3 to L5 and separated into 6 zones (zone A, zones 1-4, and zone P) comprising equal quarters of the anteroposterior diameters, and anterior and posterior to the vertebral body, to determine the distribution of Nerves at various intervertebral levels (L3-4, L4-5, and L5-S1). To determine psoas morphology, the authors examined images for a rising psoas sign at the level of L4-5, and the ratio of the anteroposterior diameter (AP) to the lateral diameter (lat), or AP/lat ratio, was calculated. They assessed the relationship between apical vertebrae, psoas major morphology, and the course of nerve tracts.RESULTSAlthough only 30% of patients in the control group showed a rising psoas sign, it was present in 100% of those in the DLS group. The psoas major was significantly extended on the concave side (AP/lat ratio: 2.1 concave side, 1.2 convex side). In 75% of patients in the DLS group, the apex of the curve was at L2 or higher (upper apex) and the psoas major was extended on the concave side. In the remaining 25%, the apex was at L3 or lower (lower apex) and the psoas major was extended on the convex side. Significant anterior shifts of Lumbar Nerves compared with controls were noted at each intervertebral level in patients with DLS. Nerves on the extended side of the psoas major were significantly shifted anteriorly. Nerve pathways on the convex side of the scoliotic curve were shifted posteriorly.CONCLUSIONSA significant anterior shift of Lumbar Nerves was noted at all intervertebral levels in patients with DLS in comparison with findings in controls. On the convex side, the Nerves showed a posterior shift. In LIF, a convex approach is relatively safer than an approach from the concave side. Lumbar nerve course tracking with DTI is useful for assessing patients with DLS before LIF.
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visualization of Lumbar Nerves using reduced field of view diffusion tensor imaging in healthy volunteers and patients with degenerative Lumbar disorders
British Journal of Radiology, 2017Co-Authors: Hirohito Kanamoto, Yawara Eguchi, Sumihisa Orita, Kazuhide Inage, Yasuhiro Oikawa, Kazuki Fujimoto, Yasuhiro Shiga, Koki Abe, Masahiro Inoue, Hideyuki KinoshitaAbstract:Objective:We investigated high resolution diffusion tensor imaging (DTI) of Lumbar Nerves with reduced field of view (rFOV) using 3 T MRI.Methods:DTI measured with rFOV was compared with conventional FOV (cFOV) 3.0 T MRI in 5 healthy volunteers and 10 patients with degenerative Lumbar disorders. The intracanal, foramina and extraforamina of the L5 nerve were established as the regions of interest and fractional anisotropy (FA) values and apparent diffusion coefficient (ADC) values were measured. Image quality for tractography and FA maps and ADC maps, interindividual and intraindividual reliability of FA and ADC, and signal-to-noise (SNR) were studied.Results:Both of image qualities with tractography, FA map and ADC map showed that Lumbar Nerves were more clearly imaged with the rFOV. Intraindividual reliability was higher with rFOV compared with the conventional method for ADC values, while interindividual reliability was higher for both FA values and ADC values with the rFOV method over the conventional...
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anatomical evaluation of Lumbar Nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach
European Spine Journal, 2017Co-Authors: Yasuhiro Oikawa, Yawara Eguchi, Sumihisa Orita, Miyako Suzuki, Kazuhide Inage, Atsuya Watanabe, Kazuyo Yamauchi, Yoshihiro Sakuma, Go Kubota, Takeshi SainohAbstract:Purpose Recently, lateral interbody fusion (LIF) has become more prevalent, and evaluation of Lumbar Nerves has taken on new importance. We report on the assessment of anatomical relationships between Lumbar Nerves and vertebral bodies using diffusion tensor imaging (DTI).
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anatomical evaluation of Lumbar Nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach
European Spine Journal, 2017Co-Authors: Yasuhiro Oikawa, Yawara Eguchi, Sumihisa Orita, Miyako Suzuki, Kazuhide Inage, Atsuya Watanabe, Kazuyo Yamauchi, Yoshihiro Sakuma, Go Kubota, Takeshi SainohAbstract:Recently, lateral interbody fusion (LIF) has become more prevalent, and evaluation of Lumbar Nerves has taken on new importance. We report on the assessment of anatomical relationships between Lumbar Nerves and vertebral bodies using diffusion tensor imaging (DTI). Fifty patients with degenerative Lumbar disease and ten healthy subjects underwent DTI. In patients with Lumbar degenerative disease, we studied nerve courses with patients in the supine positions and with hips flexed. In healthy subjects, we evaluated nerve courses in three different positions: supine with hips flexed (the standard position for MRI); supine with hips extended; and the right lateral decubitus position with hips flexed. In conjunction with tractography from L3 to L5 using T2-weighted sagittal imaging, the vertebral body anteroposterior span was divided into four equally wide zones, with six total zones defined, including an anterior and a posterior zone (zone A, zones 1–4, zone P). We used this to characterize nerve courses at disc levels L3/4, L4/5, and L5/S1. In patients with degenerative Lumbar disease, in the supine position with hips flexed, all Lumbar nerve roots were located posterior to the vertebral body centers in L3/4 and L4/5. In healthy individuals, the L3/4 nerve courses were displaced forward in hips extended compared with the standard position, whereas in the lateral decubitus position, the L4/5 and L5/S nerve courses were displaced posteriorly compared with the standard position. The L3/4 and L4/5 nerve roots are located posterior to the vertebral body center. These were found to be offset to the rear when the hip is flexed or the lateral decubitus position is assumed. The present study is the first to elucidate changes in the course of the Lumbar Nerves as this varies by position. The lateral decubitus position or the position supine with hips flexed may be useful for avoiding nerve damage in a direct lateral transpsoas approach. Preoperative DTI seems to be useful in evaluating the Lumbar nerve course as it relates anatomically to the vertebral body.
Sumihisa Orita - One of the best experts on this subject based on the ideXlab platform.
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does the increased motion probing gradient directional diffusion tensor imaging of Lumbar Nerves using multi band sense improve the visualization and accuracy of fa values
European Spine Journal, 2020Co-Authors: Masaki Norimoto, Yawara Eguchi, Sumihisa Orita, Atsuya Watanabe, Takayuki Sakai, Daichi Murayama, Masami Yoneyama, Yohei Kawasaki, Takeo Furuya, Kazuhide InageAbstract:Diffusion tensor imaging (DTI) is useful to evaluate Lumbar Nerves visually and quantitatively. Multi-band sensitivity encoding (MB-SENSE) is a technique to reduce the scan time. This study aimed to investigate if super-multi-gradient DTI with multi-band sensitivity encoding (MB-SENSE) is better in evaluating Lumbar Nerves than the conventional method. The participants were 12 healthy volunteers (mean age 33.6 years). In all subjects, DTI was performed using echo planar imaging with different motion probing gradient (MPG) directions (15 without MB, and 15, 32, 64, and 128 with MB) and the Lumbar nerve roots were visualized with tractography. In the five groups, we evaluated the resultant DTI both visually and quantitatively. For visual measures, we counted the number of fluffs and disruptions of the nerve fibers. For quantitative measures, the fractional anisotropy (FA) and standard deviation of the fractional anisotropy (FA-SD) values at two regions (proximal and distal) of the Lumbar nerve roots were quantified and compared. Among the five groups, the number of fluffs decreased as the number of MPG directions increased. However, the number of disruptions showed no significant differences. The FA-SD values decreased as the number of MPG directions increased, indicating that the signal variation was reduced with multi-gradient directional DTI. High-resolution multi-directional DTI with MB-SENSE may be useful to visualize nerve entrapments and may allow for more accurate DTI parameter quantification with opportunities for clinical diagnostic applications.
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Diffusion tensor tractography of the Lumbar Nerves before a direct lateral transpsoas approach to treat degenerative Lumbar scoliosis
Journal of Neurosurgery, 2019Co-Authors: Yawara Eguchi, Masaki Norimoto, Munetaka Suzuki, Ryota Haga, Hajime Yamanaka, Hiroshi Tamai, Tatsuya Kobayashi, Sumihisa Orita, Miyako Suzuki, Kazuhide InageAbstract:OBJECTIVEThe purpose of this study was to determine the relationship between vertebral bodies, psoas major morphology, and the course of Lumbar nerve tracts using diffusion tensor imaging (DTI) before lateral interbody fusion (LIF) to treat spinal deformities.METHODSDTI findings in a group of 12 patients (all women, mean age 74.3 years) with degenerative Lumbar scoliosis (DLS) were compared with those obtained in a matched control group of 10 patients (all women, mean age 69.8 years) with low-back pain but without scoliosis. A T2-weighted sagittal view was fused to tractography from L3 to L5 and separated into 6 zones (zone A, zones 1-4, and zone P) comprising equal quarters of the anteroposterior diameters, and anterior and posterior to the vertebral body, to determine the distribution of Nerves at various intervertebral levels (L3-4, L4-5, and L5-S1). To determine psoas morphology, the authors examined images for a rising psoas sign at the level of L4-5, and the ratio of the anteroposterior diameter (AP) to the lateral diameter (lat), or AP/lat ratio, was calculated. They assessed the relationship between apical vertebrae, psoas major morphology, and the course of nerve tracts.RESULTSAlthough only 30% of patients in the control group showed a rising psoas sign, it was present in 100% of those in the DLS group. The psoas major was significantly extended on the concave side (AP/lat ratio: 2.1 concave side, 1.2 convex side). In 75% of patients in the DLS group, the apex of the curve was at L2 or higher (upper apex) and the psoas major was extended on the concave side. In the remaining 25%, the apex was at L3 or lower (lower apex) and the psoas major was extended on the convex side. Significant anterior shifts of Lumbar Nerves compared with controls were noted at each intervertebral level in patients with DLS. Nerves on the extended side of the psoas major were significantly shifted anteriorly. Nerve pathways on the convex side of the scoliotic curve were shifted posteriorly.CONCLUSIONSA significant anterior shift of Lumbar Nerves was noted at all intervertebral levels in patients with DLS in comparison with findings in controls. On the convex side, the Nerves showed a posterior shift. In LIF, a convex approach is relatively safer than an approach from the concave side. Lumbar nerve course tracking with DTI is useful for assessing patients with DLS before LIF.
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visualization of Lumbar Nerves using reduced field of view diffusion tensor imaging in healthy volunteers and patients with degenerative Lumbar disorders
British Journal of Radiology, 2017Co-Authors: Hirohito Kanamoto, Yawara Eguchi, Sumihisa Orita, Kazuhide Inage, Yasuhiro Oikawa, Kazuki Fujimoto, Yasuhiro Shiga, Koki Abe, Masahiro Inoue, Hideyuki KinoshitaAbstract:Objective:We investigated high resolution diffusion tensor imaging (DTI) of Lumbar Nerves with reduced field of view (rFOV) using 3 T MRI.Methods:DTI measured with rFOV was compared with conventional FOV (cFOV) 3.0 T MRI in 5 healthy volunteers and 10 patients with degenerative Lumbar disorders. The intracanal, foramina and extraforamina of the L5 nerve were established as the regions of interest and fractional anisotropy (FA) values and apparent diffusion coefficient (ADC) values were measured. Image quality for tractography and FA maps and ADC maps, interindividual and intraindividual reliability of FA and ADC, and signal-to-noise (SNR) were studied.Results:Both of image qualities with tractography, FA map and ADC map showed that Lumbar Nerves were more clearly imaged with the rFOV. Intraindividual reliability was higher with rFOV compared with the conventional method for ADC values, while interindividual reliability was higher for both FA values and ADC values with the rFOV method over the conventional...
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anatomical evaluation of Lumbar Nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach
European Spine Journal, 2017Co-Authors: Yasuhiro Oikawa, Yawara Eguchi, Sumihisa Orita, Miyako Suzuki, Kazuhide Inage, Atsuya Watanabe, Kazuyo Yamauchi, Yoshihiro Sakuma, Go Kubota, Takeshi SainohAbstract:Purpose Recently, lateral interbody fusion (LIF) has become more prevalent, and evaluation of Lumbar Nerves has taken on new importance. We report on the assessment of anatomical relationships between Lumbar Nerves and vertebral bodies using diffusion tensor imaging (DTI).
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anatomical evaluation of Lumbar Nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach
European Spine Journal, 2017Co-Authors: Yasuhiro Oikawa, Yawara Eguchi, Sumihisa Orita, Miyako Suzuki, Kazuhide Inage, Atsuya Watanabe, Kazuyo Yamauchi, Yoshihiro Sakuma, Go Kubota, Takeshi SainohAbstract:Recently, lateral interbody fusion (LIF) has become more prevalent, and evaluation of Lumbar Nerves has taken on new importance. We report on the assessment of anatomical relationships between Lumbar Nerves and vertebral bodies using diffusion tensor imaging (DTI). Fifty patients with degenerative Lumbar disease and ten healthy subjects underwent DTI. In patients with Lumbar degenerative disease, we studied nerve courses with patients in the supine positions and with hips flexed. In healthy subjects, we evaluated nerve courses in three different positions: supine with hips flexed (the standard position for MRI); supine with hips extended; and the right lateral decubitus position with hips flexed. In conjunction with tractography from L3 to L5 using T2-weighted sagittal imaging, the vertebral body anteroposterior span was divided into four equally wide zones, with six total zones defined, including an anterior and a posterior zone (zone A, zones 1–4, zone P). We used this to characterize nerve courses at disc levels L3/4, L4/5, and L5/S1. In patients with degenerative Lumbar disease, in the supine position with hips flexed, all Lumbar nerve roots were located posterior to the vertebral body centers in L3/4 and L4/5. In healthy individuals, the L3/4 nerve courses were displaced forward in hips extended compared with the standard position, whereas in the lateral decubitus position, the L4/5 and L5/S nerve courses were displaced posteriorly compared with the standard position. The L3/4 and L4/5 nerve roots are located posterior to the vertebral body center. These were found to be offset to the rear when the hip is flexed or the lateral decubitus position is assumed. The present study is the first to elucidate changes in the course of the Lumbar Nerves as this varies by position. The lateral decubitus position or the position supine with hips flexed may be useful for avoiding nerve damage in a direct lateral transpsoas approach. Preoperative DTI seems to be useful in evaluating the Lumbar nerve course as it relates anatomically to the vertebral body.
Kazuhide Inage - One of the best experts on this subject based on the ideXlab platform.
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does the increased motion probing gradient directional diffusion tensor imaging of Lumbar Nerves using multi band sense improve the visualization and accuracy of fa values
European Spine Journal, 2020Co-Authors: Masaki Norimoto, Yawara Eguchi, Sumihisa Orita, Atsuya Watanabe, Takayuki Sakai, Daichi Murayama, Masami Yoneyama, Yohei Kawasaki, Takeo Furuya, Kazuhide InageAbstract:Diffusion tensor imaging (DTI) is useful to evaluate Lumbar Nerves visually and quantitatively. Multi-band sensitivity encoding (MB-SENSE) is a technique to reduce the scan time. This study aimed to investigate if super-multi-gradient DTI with multi-band sensitivity encoding (MB-SENSE) is better in evaluating Lumbar Nerves than the conventional method. The participants were 12 healthy volunteers (mean age 33.6 years). In all subjects, DTI was performed using echo planar imaging with different motion probing gradient (MPG) directions (15 without MB, and 15, 32, 64, and 128 with MB) and the Lumbar nerve roots were visualized with tractography. In the five groups, we evaluated the resultant DTI both visually and quantitatively. For visual measures, we counted the number of fluffs and disruptions of the nerve fibers. For quantitative measures, the fractional anisotropy (FA) and standard deviation of the fractional anisotropy (FA-SD) values at two regions (proximal and distal) of the Lumbar nerve roots were quantified and compared. Among the five groups, the number of fluffs decreased as the number of MPG directions increased. However, the number of disruptions showed no significant differences. The FA-SD values decreased as the number of MPG directions increased, indicating that the signal variation was reduced with multi-gradient directional DTI. High-resolution multi-directional DTI with MB-SENSE may be useful to visualize nerve entrapments and may allow for more accurate DTI parameter quantification with opportunities for clinical diagnostic applications.
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Diffusion tensor tractography of the Lumbar Nerves before a direct lateral transpsoas approach to treat degenerative Lumbar scoliosis
Journal of Neurosurgery, 2019Co-Authors: Yawara Eguchi, Masaki Norimoto, Munetaka Suzuki, Ryota Haga, Hajime Yamanaka, Hiroshi Tamai, Tatsuya Kobayashi, Sumihisa Orita, Miyako Suzuki, Kazuhide InageAbstract:OBJECTIVEThe purpose of this study was to determine the relationship between vertebral bodies, psoas major morphology, and the course of Lumbar nerve tracts using diffusion tensor imaging (DTI) before lateral interbody fusion (LIF) to treat spinal deformities.METHODSDTI findings in a group of 12 patients (all women, mean age 74.3 years) with degenerative Lumbar scoliosis (DLS) were compared with those obtained in a matched control group of 10 patients (all women, mean age 69.8 years) with low-back pain but without scoliosis. A T2-weighted sagittal view was fused to tractography from L3 to L5 and separated into 6 zones (zone A, zones 1-4, and zone P) comprising equal quarters of the anteroposterior diameters, and anterior and posterior to the vertebral body, to determine the distribution of Nerves at various intervertebral levels (L3-4, L4-5, and L5-S1). To determine psoas morphology, the authors examined images for a rising psoas sign at the level of L4-5, and the ratio of the anteroposterior diameter (AP) to the lateral diameter (lat), or AP/lat ratio, was calculated. They assessed the relationship between apical vertebrae, psoas major morphology, and the course of nerve tracts.RESULTSAlthough only 30% of patients in the control group showed a rising psoas sign, it was present in 100% of those in the DLS group. The psoas major was significantly extended on the concave side (AP/lat ratio: 2.1 concave side, 1.2 convex side). In 75% of patients in the DLS group, the apex of the curve was at L2 or higher (upper apex) and the psoas major was extended on the concave side. In the remaining 25%, the apex was at L3 or lower (lower apex) and the psoas major was extended on the convex side. Significant anterior shifts of Lumbar Nerves compared with controls were noted at each intervertebral level in patients with DLS. Nerves on the extended side of the psoas major were significantly shifted anteriorly. Nerve pathways on the convex side of the scoliotic curve were shifted posteriorly.CONCLUSIONSA significant anterior shift of Lumbar Nerves was noted at all intervertebral levels in patients with DLS in comparison with findings in controls. On the convex side, the Nerves showed a posterior shift. In LIF, a convex approach is relatively safer than an approach from the concave side. Lumbar nerve course tracking with DTI is useful for assessing patients with DLS before LIF.
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visualization of Lumbar Nerves using reduced field of view diffusion tensor imaging in healthy volunteers and patients with degenerative Lumbar disorders
British Journal of Radiology, 2017Co-Authors: Hirohito Kanamoto, Yawara Eguchi, Sumihisa Orita, Kazuhide Inage, Yasuhiro Oikawa, Kazuki Fujimoto, Yasuhiro Shiga, Koki Abe, Masahiro Inoue, Hideyuki KinoshitaAbstract:Objective:We investigated high resolution diffusion tensor imaging (DTI) of Lumbar Nerves with reduced field of view (rFOV) using 3 T MRI.Methods:DTI measured with rFOV was compared with conventional FOV (cFOV) 3.0 T MRI in 5 healthy volunteers and 10 patients with degenerative Lumbar disorders. The intracanal, foramina and extraforamina of the L5 nerve were established as the regions of interest and fractional anisotropy (FA) values and apparent diffusion coefficient (ADC) values were measured. Image quality for tractography and FA maps and ADC maps, interindividual and intraindividual reliability of FA and ADC, and signal-to-noise (SNR) were studied.Results:Both of image qualities with tractography, FA map and ADC map showed that Lumbar Nerves were more clearly imaged with the rFOV. Intraindividual reliability was higher with rFOV compared with the conventional method for ADC values, while interindividual reliability was higher for both FA values and ADC values with the rFOV method over the conventional...
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anatomical evaluation of Lumbar Nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach
European Spine Journal, 2017Co-Authors: Yasuhiro Oikawa, Yawara Eguchi, Sumihisa Orita, Miyako Suzuki, Kazuhide Inage, Atsuya Watanabe, Kazuyo Yamauchi, Yoshihiro Sakuma, Go Kubota, Takeshi SainohAbstract:Purpose Recently, lateral interbody fusion (LIF) has become more prevalent, and evaluation of Lumbar Nerves has taken on new importance. We report on the assessment of anatomical relationships between Lumbar Nerves and vertebral bodies using diffusion tensor imaging (DTI).
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anatomical evaluation of Lumbar Nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach
European Spine Journal, 2017Co-Authors: Yasuhiro Oikawa, Yawara Eguchi, Sumihisa Orita, Miyako Suzuki, Kazuhide Inage, Atsuya Watanabe, Kazuyo Yamauchi, Yoshihiro Sakuma, Go Kubota, Takeshi SainohAbstract:Recently, lateral interbody fusion (LIF) has become more prevalent, and evaluation of Lumbar Nerves has taken on new importance. We report on the assessment of anatomical relationships between Lumbar Nerves and vertebral bodies using diffusion tensor imaging (DTI). Fifty patients with degenerative Lumbar disease and ten healthy subjects underwent DTI. In patients with Lumbar degenerative disease, we studied nerve courses with patients in the supine positions and with hips flexed. In healthy subjects, we evaluated nerve courses in three different positions: supine with hips flexed (the standard position for MRI); supine with hips extended; and the right lateral decubitus position with hips flexed. In conjunction with tractography from L3 to L5 using T2-weighted sagittal imaging, the vertebral body anteroposterior span was divided into four equally wide zones, with six total zones defined, including an anterior and a posterior zone (zone A, zones 1–4, zone P). We used this to characterize nerve courses at disc levels L3/4, L4/5, and L5/S1. In patients with degenerative Lumbar disease, in the supine position with hips flexed, all Lumbar nerve roots were located posterior to the vertebral body centers in L3/4 and L4/5. In healthy individuals, the L3/4 nerve courses were displaced forward in hips extended compared with the standard position, whereas in the lateral decubitus position, the L4/5 and L5/S nerve courses were displaced posteriorly compared with the standard position. The L3/4 and L4/5 nerve roots are located posterior to the vertebral body center. These were found to be offset to the rear when the hip is flexed or the lateral decubitus position is assumed. The present study is the first to elucidate changes in the course of the Lumbar Nerves as this varies by position. The lateral decubitus position or the position supine with hips flexed may be useful for avoiding nerve damage in a direct lateral transpsoas approach. Preoperative DTI seems to be useful in evaluating the Lumbar nerve course as it relates anatomically to the vertebral body.
Masayuki Miyagi - One of the best experts on this subject based on the ideXlab platform.
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quantitative evaluation and visualization of Lumbar foraminal nerve root entrapment by using diffusion tensor imaging preliminary results
American Journal of Neuroradiology, 2011Co-Authors: Yawara Eguchi, Sumihisa Orita, Seiji Ohtori, Hiroto Kamoda, G Arai, T Ishikawa, Masayuki Miyagi, Gen Inoue, M Suzuki, Y MasudaAbstract:BACKGROUND AND PURPOSE: DTI can provide valuable structural information that may become an innovative tool in evaluating Lumbar foraminal nerve root entrapment. The purpose of this study was to visualize the Lumbar nerve roots and to measure their FA in healthy volunteers and patients with Lumbar foraminal stenosis by using DTI and tractography with 3T MR imaging. MATERIALS AND METHODS: Eight patients with Lumbar foraminal stenosis and 8 healthy volunteers underwent 3T MR imaging. In all subjects, DTI was performed with echo-planar imaging at a b-value of 800 s/mm 2 and the Lumbar nerve roots were visualized with tractography. Mean FA values in the Lumbar nerve roots were quantified on DTI images. RESULTS: In all subjects, the Lumbar nerve roots were clearly visualized with tractography. In all patients, tractography also showed abnormalities such as tract disruption, nerve narrowing, and indentation in their course through the foramen. Mean FA values were significantly lower in entrapped roots than in intact roots. CONCLUSIONS: We demonstrated that DTI and tractography of human Lumbar Nerves can visualize and quantitatively evaluate Lumbar nerve entrapment with foraminal stenosis. We believe that DWI is a potential tool for the diagnosis of Lumbar nerve entrapment.
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clinical applications of diffusion magnetic resonance imaging of the Lumbar foraminal nerve root entrapment
European Spine Journal, 2010Co-Authors: Yawara Eguchi, Munetaka Suzuki, Sumihisa Orita, Seiji Ohtori, Hiroto Kamoda, G Arai, T Ishikawa, Kazuyo Yamauchi, Masaomi Yamashita, Masayuki MiyagiAbstract:Diffusion-weighted imaging (DWI) can provide valuable structural information about tissues that may be useful for clinical applications in evaluating Lumbar foraminal nerve root entrapment. Our purpose was to visualize the Lumbar nerve root and to analyze its morphology, and to measure its apparent diffusion coefficient (ADC) in healthy volunteers and patients with Lumbar foraminal stenosis using 1.5-T magnetic resonance imaging. Fourteen patients with Lumbar foraminal stenosis and 14 healthy volunteers were studied. Regions of interest were placed at the fourth and fifth Lumbar root at dorsal root ganglia and distal spinal Nerves (at L4 and L5) and the first sacral root and distal spinal nerve (S1) on DWI to quantify mean ADC values. The anatomic parameters of the spinal nerve roots can also be determined by neurography. In patients, mean ADC values were significantly higher in entrapped roots and distal spinal nerve than in intact ones. Neurography also showed abnormalities such as nerve indentation, swelling and running transversely in their course through the foramen. In all patients, leg pain was ameliorated after selective decompression (n = 9) or nerve block (n = 5). We demonstrated the first use of DWI and neurography of human Lumbar Nerves to visualize and quantitatively evaluate Lumbar nerve entrapment with foraminal stenosis. We believe that DWI is a potential tool for diagnosis of Lumbar nerve entrapment.
Kazuyo Yamauchi - One of the best experts on this subject based on the ideXlab platform.
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anatomical evaluation of Lumbar Nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach
European Spine Journal, 2017Co-Authors: Yasuhiro Oikawa, Yawara Eguchi, Sumihisa Orita, Miyako Suzuki, Kazuhide Inage, Atsuya Watanabe, Kazuyo Yamauchi, Yoshihiro Sakuma, Go Kubota, Takeshi SainohAbstract:Purpose Recently, lateral interbody fusion (LIF) has become more prevalent, and evaluation of Lumbar Nerves has taken on new importance. We report on the assessment of anatomical relationships between Lumbar Nerves and vertebral bodies using diffusion tensor imaging (DTI).
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anatomical evaluation of Lumbar Nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach
European Spine Journal, 2017Co-Authors: Yasuhiro Oikawa, Yawara Eguchi, Sumihisa Orita, Miyako Suzuki, Kazuhide Inage, Atsuya Watanabe, Kazuyo Yamauchi, Yoshihiro Sakuma, Go Kubota, Takeshi SainohAbstract:Recently, lateral interbody fusion (LIF) has become more prevalent, and evaluation of Lumbar Nerves has taken on new importance. We report on the assessment of anatomical relationships between Lumbar Nerves and vertebral bodies using diffusion tensor imaging (DTI). Fifty patients with degenerative Lumbar disease and ten healthy subjects underwent DTI. In patients with Lumbar degenerative disease, we studied nerve courses with patients in the supine positions and with hips flexed. In healthy subjects, we evaluated nerve courses in three different positions: supine with hips flexed (the standard position for MRI); supine with hips extended; and the right lateral decubitus position with hips flexed. In conjunction with tractography from L3 to L5 using T2-weighted sagittal imaging, the vertebral body anteroposterior span was divided into four equally wide zones, with six total zones defined, including an anterior and a posterior zone (zone A, zones 1–4, zone P). We used this to characterize nerve courses at disc levels L3/4, L4/5, and L5/S1. In patients with degenerative Lumbar disease, in the supine position with hips flexed, all Lumbar nerve roots were located posterior to the vertebral body centers in L3/4 and L4/5. In healthy individuals, the L3/4 nerve courses were displaced forward in hips extended compared with the standard position, whereas in the lateral decubitus position, the L4/5 and L5/S nerve courses were displaced posteriorly compared with the standard position. The L3/4 and L4/5 nerve roots are located posterior to the vertebral body center. These were found to be offset to the rear when the hip is flexed or the lateral decubitus position is assumed. The present study is the first to elucidate changes in the course of the Lumbar Nerves as this varies by position. The lateral decubitus position or the position supine with hips flexed may be useful for avoiding nerve damage in a direct lateral transpsoas approach. Preoperative DTI seems to be useful in evaluating the Lumbar nerve course as it relates anatomically to the vertebral body.
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clinical applications of diffusion magnetic resonance imaging of the Lumbar foraminal nerve root entrapment
European Spine Journal, 2010Co-Authors: Yawara Eguchi, Munetaka Suzuki, Sumihisa Orita, Seiji Ohtori, Hiroto Kamoda, G Arai, T Ishikawa, Kazuyo Yamauchi, Masaomi Yamashita, Masayuki MiyagiAbstract:Diffusion-weighted imaging (DWI) can provide valuable structural information about tissues that may be useful for clinical applications in evaluating Lumbar foraminal nerve root entrapment. Our purpose was to visualize the Lumbar nerve root and to analyze its morphology, and to measure its apparent diffusion coefficient (ADC) in healthy volunteers and patients with Lumbar foraminal stenosis using 1.5-T magnetic resonance imaging. Fourteen patients with Lumbar foraminal stenosis and 14 healthy volunteers were studied. Regions of interest were placed at the fourth and fifth Lumbar root at dorsal root ganglia and distal spinal Nerves (at L4 and L5) and the first sacral root and distal spinal nerve (S1) on DWI to quantify mean ADC values. The anatomic parameters of the spinal nerve roots can also be determined by neurography. In patients, mean ADC values were significantly higher in entrapped roots and distal spinal nerve than in intact ones. Neurography also showed abnormalities such as nerve indentation, swelling and running transversely in their course through the foramen. In all patients, leg pain was ameliorated after selective decompression (n = 9) or nerve block (n = 5). We demonstrated the first use of DWI and neurography of human Lumbar Nerves to visualize and quantitatively evaluate Lumbar nerve entrapment with foraminal stenosis. We believe that DWI is a potential tool for diagnosis of Lumbar nerve entrapment.
