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.
ObjectiveTo evaluate the effect of reconstruction of forearm interosseous membrane (IOM) using extensor carpi radialis longus combined with radial head replacement for restoring the forearm longitudinal stability. MethodsTen fresh-frozen adult cadaveric forearms were selected, including 8 males and 2 females with a mean age of 38.2 years (range, 29-74 years). Each forearm was treated as following steps: radial head excision (group A), radial head excision+the distal ulnar radial joints separation (group B), radial head excision+the distal ulnar radial joints separation+IOM central band excision (group C), reconstructed IOM with extensor carpi radialis longus tendon (group D), radial head prothesis replacement (group E), and reconstructed IOM with extensor carpi radialis longus tendon+radial head prothesis replacement (group F). The distance between ulna and radius and radioulnar joint displacement were observed under load and non load. The force loading on both ends of specimen was recorded when the radius shifted 5 mm proximally. ResultsRestoring the radial length could maintain normal distance between radius and ulna. The interosseous membrance reconstruction could restore the load transmission between radius and ulna. The force loading specimen was (74.507±4.967), (49.227±1.940), (17.827±1.496), (24.561±1.390), (140.247±8.029), and (158.423±9.142)N in groups A, B, C, D, E, and F respectively when the radius shifted 5 mm proximally, showing significant difference among groups (P < 0.01). ConclusionReconstruction of the IOM with the extensor carpi radialis longus tendon is insufficient to restore the forearm longitudinal stability. Reconstruction using extensor carpi radialis longus tendon combined with radial head replacement may be a new choice for treatment of forearm longitudinal instability.
Objective To investigate the pathological mechanism of epileptic comorbid sleep disorder by analyzing the changes of cerebral white matter diffusion tensor in patients with sleep disorder with negative magnetic resonance imaging (MRI) epilepsy based on the method of tract-based spatial statistics (TBSS). Methods MRI negative epilepsy patients comorbid sleep disorder who were epileptic patients treated l in China-Japan Union Hospital of Jilin University from January 2020 to December 2022 completed the Epworth sleepiness scale (ESS) and Pittsburgh sleep quality index (PSQI) tests, and those who complained of sleep disorder and PSQI index ≥11 were monitored by nighttime polysomnography (PSG) and those with objective sleep disorder confirmed by PSG were included in the epilepsy comorbid sleep disorder group. Healthy volunteers with matching gender, age, education were included in the health control group. Diffusion tensor image ( DTI) was collected for all subjects by using a 3.0T magnetic resonance scanner. Diffusion parameters were compared between the two groups using TBSS. Results This study included 36 epilepsy patients comorbid sleep disorder and 35 healthy volunteers. epilepsy patients comorbid sleep disorder showed significantly lower fraction anisotropy (FA) (P<0.05) and significantly higher mean diffusivity (MD) (P<0.05) than the health control group . Brain regions with statistical differences in FA reduction included middle peduncle of cerebellum, genu of corpus callosum, body of corpus callosum, splenium of corpus callosum, anterior corona radiata, external capsule and right posterior thalamic radiation.Brain regions with statistical differences in MD degradation included genu of corpus callosum, body of corpus callosum, anterior limb of internal capsule, anterior corona radiata, superior corona radiata, external capsule and right posterior limb of internal capsul. Conclusion Patients with epilepsy comorbidities with sleep disorders have widespread and symmetric white matter damage.The white matter damage is concentrated in the front of the brain.
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.
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 evaluate the results of thumb opposition function by transferring the extensor carpi ulnaris and the extensor poll icis brevis muscle tendons. Methods Between March 2006 and August 2009, 35 patients with dysfunction of thumb opposition were treated and the thumb opposition function was reconstruced by transferring the extensor carpi ulnaris and the extensor poll icis brevis muscle tendons. There were 25 males and 10 females with an average age of 33.5 years (range, 20-53 years); 20 had median nerve injury in the wrist and 15 had median nerve injury with ulnar nerve injury. The causes were sharp instrument injury in 24 cases, blunt injury in 9 cases, and hot crush injury in 2 cases. Six cases complicated by shaft fractures of radius and ulna. All the patients underwent an operation of nerve repair at 1 to 3 hours after injury (mean, 2 hours). The time from injury to reconstructing operation was 6-14 months (mean, 7.5 months). Two cases was able to abduct thumb sl ightly, the others had no functions of thumb abduct and thumb opposition. Results All the wounds gained the primary healing. The patients were followed up 12-18 months (mean, 14 months). The wrist joint angle and thumb dorsal extension were satisfactory. Thumb abduct and thumb opposition function returned to normal in 20 patients with simple median nerve injury; in 15 patients with median nerve injury and ulnar nerve injury, thumb abduct and thumb opposition function returned to normal in 15 and 13, respectively. According to ZHAO Shuqiang’s standard, the results of thumb opposition function were normal in all patients at 12 months after operation. Conclusion It is a convenient and efficient procedure to reconstruct thumb opposition function by transferring the extensor carpi ulnaris and the extensor poll icis brevis muscle tendons.
White matter lesion (WML) of presumed vascular origin is one of the common imaging manifestations of cerebral small vessel diseases, which is the main reason of cognitive impairment and even vascular dementia in the elderly. However, there is a lack of early and effective diagnostic methods currently. In recent years, studies of diffusion tensor imaging (DTI) and resting-state functional magnetic resonance imaging (rs-fMRI) have shown that cognitive impairment in patients with WMLs is associated with disrupted white matter microstructural and brain network connectivity. Therefore, it’s speculated that DTI and rs-fMRI can be effective in early imaging diagnosis of WMLs-related cognitive impairment. This article reviews the role and significance of DTI and rs-fMRI in WMLs-related cognitive impairment.
The brain computer interface (BCI) can be used to control external devices directly through electroencephalogram (EEG) information. A multi-linear principal component analysis (MPCA) framework was used for the limitations of tensor form of multichannel EEG signals processing based on traditional principal component analysis (PCA) and two-dimensional principal component analysis (2DPCA). Based on MPCA, we used the projection of tensor-matrix to achieve the goal of dimensionality reduction and features exaction. Then we used the Fisher linear classifier to classify the features. Furthermore, we used this novel method on the BCI competitionⅡdataset 4 and BCI competitionⅣdataset 3 in the experiment. The second-order tensor representation of time-space EEG data and the third-order tensor representation of time-space-frequency EEG data were used. The best results that were superior to those from other dimensionality reduction methods were obtained by much debugging on parameter P and testQ. For two-order tensor, the highest accuracy rates could be achieved as 81.0% and 40.1%, and for three-order tensor, the highest accuracy rates were 76.0% and 43.5%, respectively.
ObjectiveTo explore the effectivenesss of simple lateral extensor digitorum communis (EDC) split approach combined with loop-plate fixation in the treatment of ulnar coronoid fracture in terrible triad of elbow (TTE).MethodsThe clinical data of 60 patients with TTE who met the selection criteria between January 2015 and May 2018 were retrospectively analyzed. There were 48 males and 12 females, aged from 18 to 60 years (mean, 37.4 years). All the patients were closed fractures. Injury causes included fall injury in 28 cases, falling from height in 20 cases, and traffic accident injury in 12 cases. All patients had no vascular and nerve injury, and the time from injury to operation was 1-14 days, with an average of 4.8 days. The height and size of the fracture of the coronal process were measured by CT and accurate classifications were made. All the 60 patients were treated with simple lateral EDC split approach combined with loop-plate to fix the ulnar coronoid fracture; 20 patients of radial head fracture were fixed with hollow screw, 32 patients with mini-plate fixation, 8 patients with radial head prosthesis replacement; 16 patients with suture and 44 patients with suture anchor to reconstruct lateral collateral ligament complex; 10 patients with residual instability of elbow joint were fixed with hinge external fixator, and others were fixed with adjustable tension brace after operation. Postoperative imaging examination was performed to evaluate fracture healing and complications, such as loosening or breakage of internal fixator, osteoarthritis, and heterotopic ossification, etc. During follow-up, the range of motion (ROM) of the elbow joint was recorded, including elbow flexion, extension, and forearm pronation, supination. Mayo elbow function score system (MEPS) was used to evaluate elbow joint function at last follow-up.ResultsAll patients were followed up 16-24 months (mean, 20.2 months). All incisions healed by first intention after operation, and no complications such as vascular nerve injury, elbow joint instability, internal fixation failure, and infection occurred; the fracture healing time was 9-17 weeks (mean, 11.7 weeks). Four cases developed elbow stiffness after operation, and all underwent elbow joint lysis with internal fixator removal within 12-15 months after operation; 10 cases developed heterotopic ossification without special treatment. At last follow-up, the ROM of elbow flexion ranged from 85° to 135° (mean, 116°), the ROM of elbow extension ranged from 0° to 20° (mean, 11°), the ROM of forearm pronation ranged from 55° to 75° (mean, 70°), and the ROM of forearm supination ranged from 60° to 90° (mean, 83°). The MEPS score ranged from 55 to 100 (mean, 86.1); the effectiveness were excellent in 40 patients, good in 10 patients, fair in 6 patients, and poor in 4 patients, with an excellent and good rate of 83.3%.ConclusionThe simple lateral EDC split approach is fully exposed, and the loop-plate can fix the ulnar coronoid fractures firmly and stably, which can restore the stability of the elbow joint, and the effectiveness is satisfactory.
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.