Diffusion tensor imaging (DTI) is a rapid development technology in recent years of magnetic resonance imaging. The diffusion tensor interpolation is a very important procedure in DTI image processing. The traditional spectral quaternion interpolation method revises the direction of the interpolation tensor and can preserve tensors anisotropy, but the method does not revise the size of tensors. The present study puts forward an improved spectral quaternion interpolation method on the basis of traditional spectral quaternion interpolation. Firstly, we decomposed diffusion tensors with the direction of tensors being represented by quaternion. Then we revised the size and direction of the tensor respectively according to different situations. Finally, we acquired the tensor of interpolation point by calculating the weighted average. We compared the improved method with the spectral quaternion method and the Log-Euclidean method by the simulation data and the real data. The results showed that the improved method could not only keep the monotonicity of the fractional anisotropy (FA) and the determinant of tensors, but also preserve the tensor anisotropy at the same time. In conclusion, the improved method provides a kind of important interpolation method for diffusion tensor image processing.
Objective To introduce a new operative technique of the expansive laminoplasty with reattachment of the spinous process and theextensor musculature for treatment of a tumor in the cervical vertebral channeland evaluate the clinical outcome of the technique. Methods From July 2003 to June 2006, this technique was applied to 26 patients (14 males,12 females; age, 25-57 years; illness course, 3 months-2 years) in our hospital. The four limbs had a muscle force of ⅢⅣ degrees, and with a high musculartension. The tendon reflex was sthenic and 2 patients had patellar clonus and ankle clonus. MRI was used to measure the tumor size (from 1.5 cm ×0.8 cm to 2.8 cm×2.0 cm, at the C3-6 levels) before and after operation.There were 8 cases at the C3,4levels, 9 cases at the C4,5 levels, 9 casesat the C5,6 levles. Results The result of the follow-up (average,8months; range, 6-12 months) showed that all the patients achieved a recovery at different degrees,with no death or complication. Although 10 of the patients felt a pain in the neck, but the pain was relieved after the functional exercise; the cervical active scope was changed a little with no cervical intervertrbal instability. The postoperative MRI and CT showed that the posterior column was maintained, and the “close-door” phenomenon did not happen. The degree of latitule of the cervical vertebra after operation was measured. The antecollis was 28.43°(37.9° onaverage). The hyposokinesis was 3244°(41° on average), the left antecollis was 25.45°(23° on average), and the right antecollis was 35.45°(36.2° on overage).Conclusion The expansive laminoplasty with reattachment of the spinous process and the extensor musculature can provide enough operative space and reserve the normal posterior column of the cervical vertebra. The intervertebral stability can beobtained after conglutination between the spinous process and the vertebral lamina.
Objective To analysis the electrophysiological dominance weight of the triceps brachii muscle/extensordigitorum communis muscle innervated by brachial plexus and to conclude its effect on the ipsilateral C7 transfer so as to offer electrophysiological data for the safety and indication of i psilateral C7 transfer. Methods From August 2007 to October 2007, 15 patients with complete brachial plexus nerve root avulsion received contralateral C7 transfer. There were 13 males and 2 females aged 18-49 years (28 years on average). Injury was caused by fall ing in 1 case, by crush in 2 cases and by traffic accident in 12 cases, involving left side in 8 cases and right side in 7 cases. The upper, middle and lower trunk of the brachial plexus were stimulated respectively, the compound muscle action potential (CMAP) at the triceps brachii muscle/extensor digitorum communis muscle was recorded, and then the electrophysiological dominance weight of the triceps brachii muscle/extensor digitorum communis muscle innervated by brachial plexus was confirmed according to the comparison of the ampl itude percentage of the CMAP by three trunks. The muscle strength of triceps brachii muscle/extensor digitorum communis muscle was evaluated and the electromyogram was taken 6 months after operation. Results All patients were followed up for 6 months. Concerning the electrophysiological dominance weight, the triceps brachii muscle was mainly innervated by uppermiddle trunk in 3 cases (20%), by middle-lower trunk in 3 cases (20%), by whole trunk in 7 cases (47%) and by middle trunk in 2 cases (13%). While the extensor digitorum communis muscle was mainly innervated by middle-lower trunk in 3 cases (20%), by whole trunk in 10 cases (67%) and by lower trunk in 2 cases (13%). Concerning the triceps brachii muscle, 2 patients got the muscle strength of 4 grade with recruitment simple phase at 1 month after operation and returned to normal at 3 month after operation, while 13 patients got the muscle strength of 5 grade with recruitment simple or mixed phase at 1 month after operation. Concerning the extensor digitorum communis muscle, the muscle strength and the recruitment phase of all 15 patients recovered to normal at 1 month after operation. Conclusion To patients with various kinds of electrophysiological dominance weight, the cutting of C7 does not substantially damage the triceps brachii muscle or extensor digitorum communis muscle, indicating that the ipsilateral C7 transfer is safe and feasible. However, it should be appl ied prudently for the patients with high dominance weight since it may result in the short-term decrease of triceps brachii muscle strength.
This study aims to determine the salient brain regions with abnormal changes in white matter structures from diffusion tensor imaging (DTI) images of the patients with temporal lobe epilepsy (TLE), and to discriminate the patients with TLE from normal controls (NCs). Firstly, the DTI images from 50 subjects (28 NCs and 22 TLE) were acquired. Secondly, the four measures including the fractional anisotropy (FA), the mean diffusivity (MD), the axial diffusivity (AD) and the radial diffusivity (RD) were calculated. Thirdly, the tract-based spatial statistics (TBSS) was adopted to extract the measures in brain regions with significant differences between the two compared groups. Fourthly, the obtained measures were used as input features of the support vector machine (SVM) for classification, and the support vector machine-recursive feature elimination (SVM-RFE) was compared with the support vector machine-tract-based spatial statistics (SVM-TBSS) method. Finally, the essential brain regions and their spatial distribution were analyzed and discussed. The experimental results showed that the FA measures of the TLE group decreased significantly in the corpus callosum, superior longitudinal fasciculus, corona radiata, external capsule, internal capsule, inferior fronto-occipital fasciculus, fasciculus uncinatus and sagittal stratum, which were nearly bilaterally distributed, while the MD and RD increased significantly in most of these brain regions of the TLE group. Although the AD also increased, the differences were not statistically significant. The SVM-TBSS classifier obtained accuracies of 82%, 76% and 76% using the FA, MD and RD for classification, respectively, and 80% using combined measures. The SVM-RFE classifier obtained accuracies of 90%, 90% and 92% using the FA, MD and RD respectively, while the highest accuracy was 100% using combined measures. These results demonstrated that the SVM-RFE outperformed the SVM-TBSS, and the dominant characteristic influencing classification in brain regions were in associative and commissural fibers. These results illustrated that the measures of DTI images could reveal the abnormal changes in white matter structure of patients with TLE, providing effective information to clarify its pathological mechanism, localize the focus and diagnose automatically.
ObjectiveTo investigate the effectiveness of modified extensor indicis proprius (EIP) tendon transfer for reconstruction of spontaneously ruptured extensor pollicis longus (EPL) tendon by comparing with the traditional EIP tendon transfer. MethodsBetween January 2009 and December 2011, 11 cases of spontaneously ruptured EPL tendon were treated by modified EIP tendon transfer to reconstruct extension function (modified group). On the base of traditional procedure, the proximal end of EPL tendon was sutured with EIP tendon and the distal end of EIP tendon was crossed round extensor pollicis brevis (EPB) tendon and sutured back with EPL tendon. A specific EI-EPL evaluation method (SEEM) was used to measure the EPL tendon function after transfer. The result was compared with that of the other 18 cases undergoing traditional operation (traditional group). There was no significant difference in gender, age, disease duration, and injury causes between 2 groups (P gt; 0.05). ResultsAll incisions healed by first intention. In traditional group, 5 cases were out of follow-up, and the other 24 cases were followed up 1 year and 6 months on average (range, 8 months-2 years and 6 months). At the last follow-up, according to the evaluation of SEEM, the thumb elevation and flexion deficits of modified group were significantly less than those of traditional group (P lt; 0.05). The independent elevation deficit of the index finger of modified group was similar to that of traditional group (P gt; 0.05). The effectiveness was excellent in 9 cases and good in 2 cases with an excellent and good rate of 100% in modified group, and was excellent in 5 cases, good in 6 cases, and fair in 2 cases with an excellent and good rate of 84.6%. The effectiveness of modified group was significantly better than that of traditional group (χ2=0.03, P=0.03). ConclusionReconstruction of EPL tendon function by modified EIP tendon transfer is effective and easy. It can increase strength of the transferred tendon and obtain satisfactory results, but the long-term effectiveness needs further follow-up.
Objective To discuss the mechanisms and clinical effect of musculus extensor hallucis longus shifting in correcting hallux valgus (HV) deformity. Methods From April 2004 to December 2006,25 cases of HV (38 feet) were treated by musculus extensor hallucis longus shifing. There were 2 men and 23 women, aging from 22-60 years (mean 46.3 years).HV angle was 21.45° (mean 31.30°), intermetatarsal(IM) angle was 7-21° (mean 12.52°). The HV were corrected by cutting osteophyma of the first metatarsal bone, cutting transverse head of adductor pollicis, transferring musculus extensor hallucis longus and reconstructing its insertion. Results The patients were followed up 6-14 months after operation. HV angle and IM angle were 7.30°±2.62° and 6.50°±2.46° respectively, showing significantdifferences when compared with before operation (Plt;0.05). According to the American Orthopaedic Foot amp; Ankle Society (AOFAS) score system, the foot function was excellent in 25 feet, good in 7 feet and poor in 6 feet,and the excellent and good rate was 84.2%. Hallux varus occurred in 2 feet after 2 months of operation, metatarsophalangeal joint limitation of motion in 2feet after 3 months of operation, no HV recurred. ConclusionThe HV deforemity can be corrected by shifting the musculus extensor hallucis longus and reconstructing its insertion. It makes stress of metatarsophalangeal joint balance and prevent recurrance of HV deformity.
ObjectiveTo compare the clinical effects of early dynamic brace passive activity program and average delay activity program after the repair of extensor tendon. MethodsSeventy-eight patients undergoing repair of the extensor tendon during the period from December 2008 to October 2011 in our hospital were randomly divided into two groups.The treatment group had 36 patients who were treated with early dynamic brace passive activity program,and the other 42 patients belonged to the control group and they accepted delay activity program.TAM and FIM were used to evaluate their clinical effects six and eight weeks after surgery,respectively. ResultsThe results of TAM and FIM of the treatment group were significantly better than those of the control group (P<0.01). ConclusionThe early dynamic brace passive activity after extensor tendon injury repair can improve the clinical effect and is worth popularizing.
In transcranial magnetic stimulation (TMS), the conductivity of brain tissue is obtained by using diffusion tensor imaging (DTI) data processing. However, the specific impact of different processing methods on the induced electric field in the tissue has not been thoroughly studied. In this paper, we first used magnetic resonance image (MRI) data to create a three-dimensional head model, and then estimated the conductivity of gray matter (GM) and white matter (WM) using four conductivity models, namely scalar (SC), direct mapping (DM), volume normalization (VN) and average conductivity (MC), respectively. Isotropic empirical conductivity values were used for the conductivity of other tissues such as the scalp, skull, and cerebrospinal fluid (CSF), and then the TMS simulations were performed when the coil was parallel and perpendicular to the gyrus of the target. When the coil was perpendicular to the gyrus where the target was located, it was easy to get the maximum electric field in the head model. The maximum electric field in the DM model was 45.66% higher than that in the SC model. The results showed that the conductivity component along the electric field direction of which conductivity model was smaller in TMS, the induced electric field in the corresponding domain corresponding to the conductivity model was larger. This study has guiding significance for TMS precise stimulation.
Objective To assess the long-time results of reconstruction of the extensor pollicis longus (EPL) function by transfer of the extensorindicis(EI). Methods From August 1978 to March 2003, 46 cases of loss of the EPL function were treatedby transfer of the extensor indicis. Of 46 cases, there were 32 males and 14 females, aged 16-51 years with an average of 36 years; there were 24 cases of oldtraumatic rupture and 22 cases of secondary rupture. The disease course was 2 days to 5 months, averaged 74 days. A specific EIEPL evaluation method (SEEM) wasused to measure the EPL function after transfer.Results Fortyone cases were followed up 9 years and 3 months on average (7 months to 23 years). Based on the SEEM, the results were excellent and good in 39 of 41 patients. The elevation deficit and combined flexion deficit were 0-2.2 cm (1.8 cm on average) and 0-3 cm (1.6 cm on average); the independent extension deficit was 0°-8° (5° on average). Conclusion Restoration of the extensor pollicis function by transfer of the extensor indicis is an effective and safe treatment option and the SEEM is a valid method for assessing EPL function.
Objective To explore the difference of white matter changes between bipolar affective disorder and schizophrenia using diffusion tensor imaging (DTI). Methods Patients with bipolar affective disorder and schizophrenia were selected from the Mental Health Center of West China Hospital of Sichuan University between October 2014 and January 2017. Volunteers were recruited from October 2014 to January 2017. The included patients were divided into bipolar affective disorder group and schizophrenia group according to their diagnosis. Volunteers were divided into normal control group. The bipolar affective disorder group was divided into two subgroups: manic episode and depressive episode. DTI was performed on the included patients and volunteers. Tract based spatial statistics (TBSS) was used to study the differences in fractional anisotropy (FA) of white matter between patients and normal controls, and FA values of two subgroups of bipolar affective disorder and schizophrenia were compared. Results A total of 99 patients and 40 normal controls were included in this study. Among them, there were 40 cases in schizophrenia group and 59 cases in bipolar affective disorder group (31 cases of manic episode and 28 cases of depressive episode). Compared with the normal control group, FA values decreased in corpus callosum, fornix, occipital forceps and left inferior longitudinal fasciculus with bipolar affective disorder group and schizophrenia group (P<0.05). There was no significant difference in FA values between bipolar affective disorder group and schizophrenia group (P>0.05), but the FA value in left posterior thalamic radiation decreased in depressive episode of bipolar affective disorder group compared with schizophrenia group (P=0.001). Conclusions There are similarities between white matter changes in bipolar affective disorder and schizophrenia. However, the white matter change in posterior thalamic radiation may be the characteristic change in depressive episode of bipolar affective disorder.