Objective To investigate whether preoperative T1 slope (T1S) in MRI can predict the changes of cervical curvature after expansive open-door laminoplasty (EOLP) in patients with cervical spondylotic myelopathy, so as to make up for the shortcomings of difficult measurement in X-ray film. Methods The clinical data of 36 patients with cervical spondylotic myelopathy who underwent EOLP were retrospectively analysed. There were 21 males and 15 females with an average age of 55.8 years (range, 37-73 years) and an average follow-up time of 14.3 months (range, 12-24 months). The preoperative X-ray films at dynamic position, CT, and MRI of cervical spine before operation, and the anteroposterior and lateral X-ray films at last follow-up were taken out to measure the following sagittal parameters. The parameters included C2-C7 Cobb angle and C2-C7 sagittal vertical axis (C2-C7 SVA) in all patients before operation and at last follow-up; preoperative T1S were measured in MRI, and the patients were divided into larger T1S group (T1S>19°, group A) and small T1S group (T1S≤19°, group B) according to the median of T1S, and the preoperative T1S, C2-C7 Cobb angle, C2-C7 SVA, and the C2-C7 Cobb angle and C2-C7 SVA at last follow-up, difference in axial distance (the difference of C2-C7 SVA before and after operation), postoperative curvature loss (the difference of C2-C7 Cobb angle before and after operation), the number of patients whose curvature loss was more than 5° after operation, and the number of patients whose kyphosis changed (C2-C7 Cobb angle was less than 0° after operation). Results The C2-C7 Cobb angle at last follow-up was significantly decreased when compared with preoperative value (t=8.000, P=0.000), but there was no significant difference in C2-C7 SVA between pre- and post-operation (t=–1.842, P=0.074). The preoperative T1S was (19.69±3.39)°; there were 17 cases in group A and 19 cases in group B with no significant difference in gender and age between 2 groups (P>0.05). The preoperative C2-C7 Cobb angle in group B was significantly lower than that in group A (t=–2.150, P=0.039), while there was no significant difference in preoperative C2-C7 SVA between 2 groups (t=0.206, P=0.838). At last follow-up, except for the curvature loss after operation in group B was significantly lower than that in group A (t=–2.723, P=0.010), there was no significant difference in the other indicators between 2 groups (P>0.05). Conclusion Preoperative larger T1S (T1S>19°) in MRI had a larger preoperative lordosis angle, but more postoperative physiological curvature was lost; preoperative T1S in MRI can not predict postoperative curvature loss, but preoperative larger T1S may be more prone to kyphosis.
ObjectiveTo investigate the diagnostic value of spectral saturation inversion recovery, gradient-echo chemical shift MRI， and proton magnetic resonance spectroscopy in quantifying hepatic fat content. MethodsConventional T1-weighted and T2-weighted scanning (without fat saturation and with fat saturation)， gradient-echo T1W in-phase （IP） and opposedphase （OP） images and 1H-MRS were performed in 31 healthy volunteers and 22 patients who were candidates for liver surgery. Signal intensities of T1WI amp; T1WIFS (SInonfat1, SIfat1), T2WI amp; T2WI-FS (SInonfat2, SIfat2), and IP amp; OP (SIin, SIout) were measured respectively, the relative signal intensity one (RSI1), relative signal intensity two (RSI2)， and fat index (FI) were calculated. Peak values and the area under peak of 1H-MRS were measured, and the relative lipid content of liver cells (RLC ) were calculated. Twenty-two patients accepted liver resection and histological examination after MRI scanning, the proportion of fatty degenerative cells were calculated by image analysis software. Results①Hepatic steatosis group showed higher average values of RSI1, FI， and RLC to non-hepatic steatosis group (Plt;0.05), while there was no significant difference in RSI2 between two groups (Pgt;0.05). ②There was a statistical significant difference in RLC among different histopathological grades of hepatic steatosis, and RLC increased in parallel with histopathological grade (Plt;0.05).There was no significant difference in RSI2, RSI1, and FI among different histopathological grades, although the latter two had a tendency of increasing concomitant with histopathological grade (Pgt;0.05). ③The values of FI and RLC were positively correlated with the PFDC （r=0468, P=0.027； r＝0771， Plt;0.000 1）, while they were not in RSI1 and RSI2 (r=0.411, P=0.057； r=0.191, P=0.392). ConclusionsSPIR, Gradient-echo chemical shift MRI and 1H-MRS can help to differentiate patients with hepatic steatosis from normal persons, the latter also can help to classify hepatic steatosis. In quantifying hepatic fat content, 1H-MRS is superior to gradient-echo chemical shift MRI, while SPIR’s role is limited.
ObjectiveTo summarize the relationship between lateral femoral notch sign (LFNS) and anterior cruciate ligament (ACL) rupture. MethodsThe relevant literature of LFNS at home and abroad in recent years was retrospectively reviewed, and its mechanism, diagnostic criteria and influencing factors in diagnosis of ACL rupture were summarized and analyzed.ResultsThe LFNS is associated with rotational stability of the knee. As an indirect sign of ACL rupture, the LFNS has high clinical diagnostic value, especially the diagnosis of ACL rupture with lateral meniscus injury.ConclusionThe diagnostic criteria and influencing factors of LFNS in diagnosis of ACL rupture are still unclear and controversial, which needs further study.
ObjectiveTo study the anatomical characteristics of blood vessels in the lateral segment of the vertebral body through the surgical approach of oblique lumbar interbody fusion (OLIF) using MRI imaging, and evaluate its potential vascular safety zone. Methods The lumbar MRI data of 107 patients with low back and leg pain who met the selection criteria between October 2019 and November 2022 were retrospectively analyzed. The vascular emanation angles, vascular travel angles, and the length of vessels in the lateral segments of the left vertebral body of L1-L5, as well as the distance between the segmental vessels in different Moro junctions of the vertebral body and their distances from the edges of the vertebrae in the same sequence (bottom marked as I, top as S) were measured. The gap between the large abdominal vessels and the lateral vessels of the vertebral body was set as the lateral vascular safe zones of the lumbar spine, and the extent of the safe zones (namely the area between the vessels) was measured. The anterior 1/3 of the lumbar intervertebral disc was taken as the simulated puncture center, and the area with a diameter of 22 mm around it as the simulated channel area. The proportion of vessels in the channel was further counted. In addition, the proportions of segmental vessels at L5 without a clear travel and with an emanation angel less than 90° were calculated. Results Except for the differences in the vascular emanation angles between L4 and L5, the vascular travel angles between L1, L2 and L4, L5, and the length of vessels in the lateral segments of the vertebral body among L1-L4 were not significant (P>0.05), the differences in the vascular emanation angles, vascular travel angles, and the length of vessels between the rest segments were all significant (P<0.05). There was no significant difference in the distance between vessels of L1, L2 and L2, L3 at Moro Ⅰ-Ⅳ junctions (P>0.05), in L3, L4 and L4, L5 at Ⅱ and Ⅲ junction (P>0.05). There was no significant difference in the vascular distance of L2, L3 between Ⅱ, Ⅲ junction and Ⅲ, Ⅳ junction, and the vascular distance of L3, L4 between Ⅰ, Ⅱ junction and Ⅲ, Ⅳ junction (P>0.05). The vascular distance of the other adjacent vertebral bodies was significant different between different Moro junctions (P<0.05). Except that there was no significant difference in the distance between L2I and L3S at Ⅰ, Ⅱ junction, L3I and L4S at Ⅱ, Ⅲ junction, and L2I and L3S at Ⅲ, Ⅳ junction (P>0.05), there was significant difference of the vascular distance between the bottom of one segment and the top of the next in the other segments (P<0.05). Comparison between junctions: Except for the L3S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ junction, and L5S between Ⅰ, Ⅱ junction and Ⅱ, Ⅲ and Ⅲ, Ⅳ junctions had no significant difference (P>0.05), there were significant differences in the distance between the other segmental vessels and the vertebral edge of the same sequence in different Moro junctions (P<0.05). The overall proportion of vessels in the simulated channels was 40.19% (43/107), and the proportion of vessels in L1 (41.12%, 44/107) and L5 (18.69%, 20/107) was higher than that in the other segments. The proportion of vessels in the channel of Moro zone Ⅰ (46.73%, 50/107) and zone Ⅱ (32.71%, 35/107) was higher than that in the zone Ⅲ, while no segmental vessels in L1 and L2 were found in the channel of zone Ⅲ (χ2=74.950, P<0.001). Moreover, 26.17% (28/107) of the segmental vessels of lateral L5 showed no movement, and 27.10% (29/107) vascular emanation angles of lateral L5 were less than 90°. Conclusion L1 and L5 segmental vessels are most likely to be injured in Moro zones Ⅰ and Ⅱ, and the placement of OLIF channels in L4, 5 at Ⅲ, Ⅳ junction should be avoided. It is usually safe to place fixation pins at the vertebral body edge on the cephalic side of the intervertebral space, but it is safer to place them on the caudal side in L1, 2 (Ⅰ, Ⅱ junction), L3, 4 (Ⅲ, Ⅳ junction), and L4, 5 (Ⅱ, Ⅲ, Ⅳ junctions).
Objective To evaluate the value of MRI in diagnosis of obstetrical brachial plexus palsy pre-gangl ionic injury. Methods From November 2006 to February 2008, 10 patients with obstetrical brachial plexus palsy were treated, 8 males and 2 females, aged from 2 months to 3 years (11.4 months on average). There were 7 cases of left side and 3 of right side.According to Tassin classification, 2 cases were type II, 6 type III and 2 type IV. All patients were performed MRI examinations before the operation, whose results were compared with those of exploration during the operation. Results MRI examinations showed 1 patient was normal and 9 patients had post-traumatic spinalmeningolcele. The 6 patients had displacement of spinal cord (4 towards the healthy side and 2 towards the sick side), 6 had deformity of spinal cord, and 2 had avulsed nerve root thickening. MRI detected 19 nerve roots were positive, 16 were true positive and 3 false positive in surgical exploration. MRI detected 6 nerve roots were negative, 4 were true negative and 2 false negative in surgical exploration. The sensitivity, specificity and accuracy of MRI in diagnosis of obstetrical brachial plexus palsy pre-gangl ionic injury were 84.2%, 80.0% and 83.3%, respectively. There were significant differences in the results by preoperative MRI examinations and by exploration during the operation (P lt; 0.05). Conclusion MRI can show pre-gangl ionic injury of brachial plexus of the patients with obstetrical brachial plexus palsy and can supply references for early diagnosis and operation time. MRI can be routinely conducted as a preoperative examination.
Objective To summarize the advances in MRI-based bone quality scoring systems and their clinical applications. Methods A comprehensive literature review was conducted on recent studies related to the MRI-based bone quality scoring system, focusing on measurement methods, influencing factors, and clinical significance. Results Osteoporosis has a high incidence in China, significantly impacting patients’ quality of life and the postoperative outcomes of related orthopedic surgeries. Early identification of osteoporosis holds important clinical significance. In recent years, both domestic and international research has enriched the MRI-based bone quality scoring systems, which includes vertebral bone quality scoring, endplate bone quality scoring, and pedicle bone quality scoring. Compared to the “gold standard” of bone density measurement, dual-energy X-ray absorptiometry, the bone quality scoring systems demonstrate good efficacy in identifying abnormal bone mass and predicting postoperative complications, while being less influenced by degenerative changes in the lumbar spine, indicating its important clinical application value. ConclusionThe MRI-based bone quality scoring systems have good value in clinical applications. However, current studies are mostly retrospective cohort and case-control studies, which carry a risk of bias. The clinical application value needs further clarification through meta-analysis and large-scale prospective studies.
Objective Platelet-rich plasma (PRP) can stimulate intervertebral disc cell proliferation, promote extracellular matrix synthesis, and inhibit annulus fibrosus cell apoptosis. To investigate the effects of autologous PRP on the treatment of the early intervertebral disc degeneration (IDD) so as to provide the experimental basis for its clinical application. Methods Forty-five healthy New Zealand white rabbits (male or female, weighing 2.5-3.0 kg) were randomly divided into the experimental group (n=15), the control group (n=15), and the sham group (n=15). PRP was prepared from the arterial blood of rabbit’s ears of the experimental group with Landesberg’s method. The platelet concentrations in both whole blood and PRP were detected. The rabbit model of early IDD was established by annulus fibrosus puncture (L4, 5, L5, 6) in both the experimental group and the control group; 100 ?L autologous PRP and 100 ?L PBS were injected into the degenerative intervertebral discs respectively after 2 weeks of models creation. In sham group, intervertebral discs were separated and exposed without treatment. The general conditions of the rabbits were observed after building models; at 2 weeks after degeneration, 1 and 2 weeks after intervention, 5 rabbits were selected randomly from each group respectively for MRI observation, histological observation by using HE staining and collagen type II immunohistochemical staining. The signal of lumbar MRI was assessed and the contents of collagen type II were detected. Results The platelet concentration of PRP was about 4.92 times as much as that of the whole blood. All the animals survived to the end of the experiment. At 2 weeks after degeneration, a lower T2 signal was observed in both the experimental group and the control group; the nucleus pulposus cells decreased and extracellular matrix degenerated; and the expression of collagen type II decreased in both the experimental group and control group. The degenerative grade of lumbar MRI in the experimental group and control group were significantly higher than that in the sham group (P lt; 0.05), and the content of collagen type II were significantly lower than that in the sham group (P lt; 0.05). At 1, 2 weeks after intervention, disc degeneration in the experimental group was significantly lower than that in control group (P lt; 0.05), and significant difference was found between experimental group and sham group (P lt; 0.05). The nucleus pulposus cells and chondroid matrix in the experimental group were more than those in the control group, showing slight stromal fibrosis; but the expression of collage type II was significantly higher than that in the control group (P lt; 0.05). Conclusion The disc injection of autologous PRP may terminate or even reverse the progress of rabbit early IDD, which may be associated with the role of multiple growth factors of PRP in regulating cell function, improving the tissue microenvironment, and promoting tissue regeneration.
ObjectiveTo summarize the status and progress of imaging studies of pancreatic neuroendocrine neoplasms (pNENs).MethodThe relevant literatures published recently at domestic and abroad about the imaging of pNENs were collected and reviewed.ResultsDue to poor visibility of pancreatic body and tail, the application of ultrasound (US) was limited. Compared with US, endoscopic ultrasound (EUS) and contrast-enhanced ultrasound (CEUS) could improve the detection rate of pNENs. The ability of plain CT scans to differentiate pathological grades was still controversial, but the value of enhanced scan was higher. CT texture analysis was feasible in the discrimination of nonhypervascular pNENs and pancreatic ductal adenocarcinoma (PDAC). Teta2 was the parameter with the highest diagnostic performance. The enhanced features of MRI were similar to CT. Combined with the apparent diffusion coefficient (ADC) value, the diagnostic and classification capabilities of MRI were improved, and the sensitivity and specificity of different ADC thresholds were also different. 68Ga-tetraazacyclododecane tetraacetic acid (68Ga-DOTA) peptide PET-CT had good preliminary diagnostic value for well-differentiated pNENs, and 18Fluoro-fluorodeoxyglucose (18F-FDG) PET-CT had limited diagnostic value.ConclusionsSomatostatin receptor imaging is of high diagnostic value and can guide clinical treatment and predict prognosis, but it has not been widely used in China. Conventional morphological images have advantages in the diagnosis and classification of pNENs. Therefore, it is important to choose a proper image inspection method.
ObjectiveTo explore the predictive value of the nerve root sedimentation sign in the diagnosis of lumbar spinal stenosis (LSS). Methods Between January 2019 and July 2021, 201 patients with non-specific low back pain (NS-LBP) who met the selection criteria were retrospectively analyzed. There were 67 males and 134 females, with an age of 50-80 years (mean, 60.7 years). Four intervertebral spaces (L1, 2, L2, 3, L3, 4, L4, 5) of each case were studied, with a total of 804. The nerve root sedimentation sign was positive in 126 intervertebral spaces, and central canal stenosis was found in 203 intervertebral spaces. Progression to symptomatic LSS was determined by follow-up for lower extremity symptoms similar to LSS, combined with central spinal stenosis. Univariate analysis was performed for gender, age, visual analogue scale (VAS) score for low back pain at initial diagnosis, treatment, dural sac cross-sectional area at each intervertebral space, number of spinal stenosis segments, lumbar spinal stenosis grade, positive nerve root sedimentation sign, and number of positive segments between patients in the progression group and non-progression group, and logistic regression analysis was further performed to screen the risk factors for progression to symptomatic LSS in patients with NS-LBP. ResultsAll patients were followed up 17-48 months, with an average of 32 months. Of 201 patients with NS-LBP, 35 progressed to symptomatic LSS. Among them, 33 cases also had central spinal stenosis, which was defined as NS-LBP progressing to symptomatic LSS (33 cases in progression group, 168 cases in non-progression group). Univariate analysis showed that CSA at each intervertebral space, the number of spinal stenosis segments, lumbar spinal stenosis grade, whether the nerve root sedimentation sign was positive, and the number of nerve root sedimentation sign positive segments were the influencing factors for the progression to symptomatic LSS (P<0.05); and further logistic regression analysis showed that positive nerve root sedimentation sign increased the risk of progression of NS-LBP to symptomatic LSS (OR=8.774, P<0.001). ConclusionThe nerve root sedimentation sign may be associated with the progression of NS-LBP to symptomatic LSS, and it has certain predictive value for the diagnosis of LSS.
Objective To develop a modified short time inversion recovery (STIR) sequence grading system for lumbar intervertebral disc degeneration based on MRI STIR sequences, and to test the validity and reproducibility of this grading system. Methods A modified 8-level grading system for lumbar intervertebral disc degeneration based on routine sagittal STIR sequences and modified Pfirrmann grading system was developed. Between April 2011 and February 2012, 60 patients with different degrees of lumbar intervertebral disc degeneration were selected as objects of study, including 32 males and 28 females with an average of 50 years (range, 17-85 years). T2 weighted and STIR sequence images were obtained from the lumbar discs of L1, 2-L5, S1 of each object (total, 300 discs). All examinations were analyzed independently by 3 observers and a consensus readout was performed after all data collected. The validity and reproducibility were analyzed by calculating consistent rate and Kappa value. Results According to the grading system, there were 0 grade 1, 83 (27.7%) grade 2, 87 (29.0%) grade 3, 66 (22.0%) grade 4, 31 (10.3%) grade 5, 15 (5.0%) grade 6, 12 (4.0%) grade 7, and 6 (2.0%) grade 8. Intra-observer consistency was b (Kappa value range, 0.822-0.952), and inter-observer consistency was high to b (Kappa value range, 0.749-0.843). According to the consensus analysis, the total consistent rate was 82.7%-92.7% (mean, 85.6%). A difference of one grade occurred in 13.9% and a difference of two or more grades in 0.5% of all the cases. Conclusion Disc degeneration can be graded by using modified STIR sequence grading system, which can improve the accuracy of grading different degrees of lumbar intervertebral disc degeneration.