Yoshitada Masuda

Diffusion magnetic resonance imaging to differentiate degenerative from infectious endplate abnormalities in the lumbar spine.

Study Design. A retrospective observational study of healthy volunteers and patients with degenerative and infectious endplate abnormalities in the lumbar spine. Objectives. Our purpose was to evaluate the usefulness of diffusion-weighted imaging (DWI) for the differentiation of degenerative and infectious endplate abnormalities using 1.5-T magnetic resonance imaging (MRI). Summary of Background Data. DWI can provide valuable structural information about tissues that may be useful for clinical applications in differentiation between degenerative and infectious endplate abnormalities. Methods. Sixteen consecutive patients with endplate abnormalities that was detected by MRI of the lumbar spine, and 15 healthy volunteers were studied. DWI was performed using whole-body imaging with background body signal suppression with a b value of 1000 s/mm2. Apparent diffusion coefficient values of normal and abnormal vertebral bone marrow were calculated. Results. Twenty-nine vertebral abnormalities were found in 16 patients. Nine vertebral abnormalities in 5 patients were because of infections and 20 vertebral abnormalities in 11 patients were because of degenerative changes; 7 levels were classified as Modic type 1, 7 levels as type 2, and 6 levels as type 3. DWI showed hyperintensity in all patients with infection, similar to that used in positron emission tomography, but not in the intervertebral spaces of any patients with degenerative disease. Apparent diffusion coefficient values of infectious bone marrowwere significantly higher than normal and degenerative bone marrow. Conclusion. DWI is useful for differentiation of degenerative and infectious endplate abnormalities. Moreover, MRI is widely used clinically because of the lack of ionizing radiation, low cost, and fast imaging time as compared with positron emission tomography. Therefore, DWI has the potential to be used as a screening tool.

In vivo 3-dimensional analysis of scapular and glenohumeral kinematics: comparison of symptomatic or asymptomatic shoulders with rotator cuff tears and healthy shoulders.

BACKGROUND Alteration in shoulder kinematics has been suggested as one cause of symptoms in shoulders with rotator cuff tears (RCTs). However, only a few studies comparing symptomatic and asymptomatic RCTs using kinematic analysis have been performed. The purpose of this study was to compare 3-dimensional (3D) scapular and glenohumeral kinematics during scapular-plane abduction among symptomatic RCTs, asymptomatic RCTs, and healthy shoulders. METHODS This study included 7 healthy shoulders in subjects with a mean age of 62 years, 5 symptomatic RCTs in subjects with a mean age of 70 years, and 7 asymptomatic RCTs in subjects with a mean age of 67 years. All shoulders with RCTs had medium-sized tears (1-3 cm in the coronal plane) that were confirmed with magnetic resonance imaging. Biplane fluoroscopic images during scapular-plane abduction were recorded, and computed tomography-derived 3D bone models were matched with the silhouettes of the bones on the fluoroscopic images using 3D/2-dimensional model-image registration techniques. Angular values of the scapula and glenohumeral kinematics were compared among the 3 groups. RESULTS Posterior tilt of the scapula was significantly smaller in the symptomatic RCTs (3.1° ± 1.8°) than in healthy shoulders (10.4° ± 0.8°) (P = .049). The humerus of the symptomatic shoulders was less externally rotated relative to the scapula throughout the activity than the healthy shoulders and asymptomatic RCTs (P = .006 and P = .028 respectively). However, there were no kinematic differences between the asymptomatic RCTs and healthy shoulders. CONCLUSION Kinematic changes in symptomatic RCTs might be associated with development of symptoms. Improvement of these kinematic changes may be a key to successful conservative treatment for symptomatic RCTs.

Use of preoperative, 3-dimensional magnetic resonance cholangiopancreatography in pediatric choledochal cysts

BACKGROUND Standard choledochal cyst (CC) operations involve dilated extrahepatic bile duct excision followed by biloenterostomy. However, biliary variants and associated intrahepatic bile duct (IHBD) stenoses or dilatations triggering postoperative sequelae require additional procedures. The usefulness of preoperative 3-dimensional magnetic resonance cholangiopancreatography (3D MRCP) and virtual cholangioscopy (VES) for observing biliary morphology and pancreaticobiliary maljunction (PBM) was evaluated. METHODS In 16 pediatric CC patients (age range, 4 months to 9 years; median, 3 years), visualization of PBM and aberrant bile duct anatomy and IHBD morphology at the hepatic hilum (HH), umbilical portion (UP), and posterior branch (POST) were compared between 3D-MRCP and intraoperative cholangiography (IOC). VES and intraoperative cholangioscopy (IOS) findings were compared. RESULTS HH, UP, and POST visualization rates were 100%, 94%, and 94%, respectively, by 3D-MRCP, and 100%, 69%, and 69%, respectively, by IOC. IHBD stenosis detection rates at each region were 38%, 13%, and 13%, respectively, by 3D-MRCP, and 25%, 0%, and 9%, respectively, by IOC. IHBD dilatation detection rates at each part were 75%, 47%, and 60%, respectively, by 3D-MRCP, and 88%, 82%, and 91%, respectively, by IOC. PBM was confirmed in 56% and 93% of cases on 3D-MRCP and IOC, respectively. Both 3D-MRCP and IOC showed biliary variants in 5 cases (31%). VES showed membranous strictures at HH, UP, and POST in 6, 2, and 2 cases, respectively, whereas IOS did so at HH in 4 cases and POST in 2. CONCLUSION Preoperative 3D-MRCP and VES accurately depict biliary morphology, allowing concrete operative planning in pediatric CC patients, complementing IOC and IOS.

Reduced Field-of-View Diffusion Tensor Imaging of the Spinal Cord Shows Motor Dysfunction of the Lower Extremities in Patients with Cervical Compression Myelopathy:

Study Design. A cross-sectional study. Objective. The aim of this study was to quantify spinal cord dysfunction at the tract level in patients with cervical compressive myelopathy (CCM) using reduced field-of-view (rFOV) diffusion tensor imaging (DTI). Summary of Background Data. Although magnetic resonance imaging (MRI) is the standard used for radiological evaluation of CCM, information acquired by MRI does not necessarily reflect the severity of spinal cord disorder. There is a growing interest in developing imaging methods to quantify spinal cord dysfunction. To acquire high-resolution DTI, a new scheme using rFOV has been proposed. Methods. We enrolled 10 healthy volunteers and 20 patients with CCM in this study. The participants were studied using a 3.0-T MRI system. For DTI acquisitions, diffusion-weighted spin-echo rFOV single-shot echo-planar imaging was used. Regions-of-interest (ROI) for the lateral column (LC) and posterior column (PC) tracts were determined on the basis of a map of fractional anisotropy (FA) of the spinal cord and FA values were measured. The FA of patients with CCM was compared with that of healthy controls and correlated with Japanese Orthopaedic Association (JOA) score. Results. In LC and PC tracts, FA values in patients with CCM were significantly lower than in healthy volunteers. Total JOA scores correlated moderately with FA in LC and PC tracts. JOA subscores for motor dysfunction of the lower extremities correlated strongly with FA in LC and PC tracts. Conclusion. It is feasible to evaluate the cervical spinal cord at the tract level using rFOV DTI. Although FA values at the maximum compression level were not well correlated with total JOA scores, they were strongly correlated with JOA subscores for motor dysfunction of the lower extremities. Our findings suggest that FA reflects white matter dysfunction below the maximum compression level and FA can be used as an imaging biomarker of spinal cord dysfunction. Level of Evidence: 4

Recommended acquisition-parameters in achieving successful evaluation of coronary lumen patency surrounded by XIENCE of diameters<3.0mm in 1st generation 320-slice CT. XIENCE Phantom Study Part 1.

Recommended acquisition-parameters in achieving successful evaluation of coronary lumen patency surrounded by XIENCE of diameters b3.0 mm in 1st generation 320-slice CT. XIENCE Phantom Study Part 1 Nobusada Funabashi ⁎, Yasuaki Namihira , Ryosuke Irie , Yoshihide Fujimoto , Toshihiro Shoji , Hiroyuki Takaoka , Hironori Kondo , Kanako Atou , Joji Ota , Yoshitada Masuda , Takashi Uno , Yoshio Kobayashi a

Optical stent-sizes in evaluating patency of coronary lumen surrounded by XIENCE of actual diameters 2.21-2.85 mm in 1st-generation 320-slice-CT using Pulsating-Phantom XIENCE phantom study part 5

Optical stent-sizes in evaluating patency of coronary lumen surrounded by XIENCE of actual diameters 2.21–2.85 mm in 1st-generation 320-slice-CT using Pulsating-Phantom XIENCE phantom study part 5 Nobusada Funabashi ⁎, Yasuaki Namihira , Ryosuke Irie , Yoshihide Fujimoto , Toshihiro Shoji , Hiroyuki Takaoka , Hironori Kondo , Kanako Atou , Joji Ota , Yoshitada Masuda , Takashi Uno , Yoshio Kobayashi a

4D MR imaging of respiratory organ motion using an intersection profile method

We propose an intersection profile method for reconstructing a 4D-MRI of respiratory organ motion from time sequential images of 2D-MRI. In the proposed method, first, time sequential MR images in many coronal planes set to widely cover the lung region are acquired as the data slices. Second, the time sequential MR images in a proper sagittal plane are acquired as the navigator slice. 4D-MRI is reconstructed by extracting and combining a proper respiratory pattern from each data slice which is most similar to an adequately selected respiratory pattern in the navigator slice on the intersection between the navigation slice and each data slice. Successful visualization of the respiratory organ motion is demonstrated and the validation of reconstruction is also presented. Such a 4D-MRI has a great potential for many medical applications. In this paper, we further propose to construct a diaphragmatic function map from a 4D-MRI reconstructed by the intersection profile method to evaluate diaphragmatic motion quantitatively. Experimental results using three healthy volunteers and three patients are shown.

Anatomical evaluation of lumbar nerves using diffusion tensor imaging and implications of lateral decubitus for lateral transpsoas approach

PurposeRecently, 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).MethodsFifty 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.ResultsIn 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.ConclusionsThe 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.

Correlation between Morphologic Changes and Autism Spectrum Tendency in Obsessive-Compulsive Disorder

OBJECTIVES Obsessive-compulsive disorder (OCD) is one of the most debilitating psychiatric disorders, with some speculating that a reason for difficulty in its treatment might be its coexistence with autism spectrum. We investigated the tendency for autistic spectrum disorders (ASD) in patients with OCD from a neuroimaging point of view using voxel-based morphometry. METHODS We acquired T1-weighted images from 20 patients with OCD and 30 healthy controls and investigated the difference in regional volume between the groups as well as the correlation between Autism-Spectrum Quotient (AQ) scores and regional cerebral volumes of patients with OCD. RESULTS Volumes in the bilateral middle frontal gyri were significantly decreased in patients with OCD compared to controls. Correlational analysis showed significant positive correlations between AQ scores and regional gray matter (GM) volumes in the left dorsolateral prefrontal cortex (DLPFC) and left amygdala. Furthermore, GM volumes of these regions were positively correlated with each other. CONCLUSIONS The positive correlation of ASD traits in patients with OCD with regional GM volumes in the left DLPFC and amygdala could reflect the heterogeneity of patient symptoms. Our results suggest that differences in GM volume might allow classification of patients with OCD for appropriate therapy based on their particular traits.

Cognitive-Behavioral Therapy for Obsessive–Compulsive Disorder with and without Autism Spectrum Disorder: Gray Matter Differences Associated with Poor Outcome

Cognitive behavioral therapy (CBT) is an effective treatment for obsessive–compulsive disorder (OCD) and is also applicable to patients with both OCD and autism spectrum disorder (ASD). However, previous studies have reported that CBT for patients with both OCD and ASD might be less effective than for patients with OCD alone. In addition, there is no evidence as to why autistic traits might be risk factors. Therefore, we investigated whether comorbidity between ASD and OCD may significantly affect treatment outcome and discovered predictors of CBT outcomes using structural magnetic resonance imaging (MRI) data. A total of 39 patients, who were diagnosed with OCD, were enrolled in this study. Of these, except for 2 dropout cases, 15 patients were diagnosed with ASD, and 22 patients were diagnosed with OCD without ASD. Both groups took CBT for 11–20 sessions. First, to examine the effectiveness of CBT for OCD patients with and without ASD, we compared CBT outcomes between the two groups. Second, to investigate how the structural abnormality profile of the brain at pretreatment influenced CBT outcomes, we performed a structural MRI comparison focusing on the gray matter volume of the whole brain in both patients with only OCD, and those with both OCD and ASD. In order to discover neurostructural predictors of CBT outcomes besides autistic traits, we divided our samples again into two groups of those who did and those who did not remit after CBT, and repeated the analysis taking autistic traits into account. The results showed that OCD patients with ASD responded significantly less well to CBT. The OCD patients with ASD had much less gray matter volume in the left occipital lobe than OCD patients without ASD. The non-remission group had a significantly smaller volume of gray matter in the left dorsolateral prefrontal cortex (DLPFC) compared with the remission group, after having partialed out autistic traits. These results indicate that the abnormalities in DLPFC negatively affect the CBT outcome, regardless of the severity of the autistic traits.