Objective To detect the cell density, apoptotic rate, and the expressions of BNIP3 in nucleus pulposus of degenerative intervertebral disc of rabbits, so as to further understand the mechanism of intervertebral disc degeneration. Methods Thirty male New Zealand white rabbits, aging 3 months and weighing (2.3 ± 0.2) kg, were divided into sham operation group (control group, n=10) and intervertebral disc degeneration model group (experimental group, n=20). Interbertebral disc degeneration models were establ ished by puncture of L3,4, L4,5, and L5,6 intervertebral discs in the experimental group; intervertebral discs were exposed only and then sutured in the control group. The degree of intervertebral disc degeneration was evaluated according to Pfirrmann classification by MRI at 4 and 8 weeks after establ ishing models. Apototic cells were determined by TUNEL and histological methods, and the immunohistochemical staining was performed to detect the expressions of BNIP3 in nucleus pulposus of intervertebral disc. Results MRI examination showed that the signal intensity decreased gradually at 4 and 8 weeks in the experimental group. There wassignificant difference in the degree of intervertebral disc degeneration between at 4 weeks and at 8 weeks in the experimental group (P lt; 0.05). The histological observation and TUNEL test showed that high density of nucleus pulposus cells and only a few apoptotic cells were observed in the control group; at 4 and 8 weeks, the density of nucleus pulposus cells decreased gradually with more apoptotic cells in the experimental group. There were significant differences in the nucleus pulposus cell density and positive rate of TUNEL staining between 2 groups, and between at 4 weeks and at 8 weeks in the experimental group (P lt; 0.05). The expression of BNIP3 of nucleus pulposus was negative in the control group; however, in the experimental group, the positive expression rates of BNIP3 of nucleus pulposus (the gray values) were 13.45% ± 1.16% and 32.00% ± 1.82% (194.32 ± 4.65 and 117.54 ± 2.11) at 4 and 8 weeks respectively, showing significant differences (P lt; 0.05). Conclusion The decrease of cell density in nucleus pulposus is involved in the development of intervertebral disc degeneration. Cell apoptosis is one of reasons in the decrease of nucleus pulposus cell; BNIP3 is involved in nucleus pulposus cell apoptosis in the degenerative intervertebral disc.
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 study the feasibility of virtual intercondylar notchplasty by applying MRI two-dimensional (2D) images to reconstruct three-dimensional (3D) images and measure the size of intercondylar notch. Methods Thirty healthy volunteers who had no knee joint disease and surgery history were selected. There were 15 females and 15 males with an age range of 20-30 years, weight range of 45-74 kg, and height range of 150-185 cm. They were divided into male group and female group, and the knees of each group were divided into 2 subgroups (the left group and right group). MRI scan of the left and right knees was performed, and the 2D images of MRI were imported into Mimics10.01 medical image control system for 3D reconstruction. The related anatomical data as follows were measured from the 3D digital model and analyzed by statistical software: notch width (NW), condylar width (CW), and notch width index (NWI). Then the 3D knee images of patients with anterior cruciate ligament (ACL) injury were collected between January and March 2010, and 4 patients with narrow intercondylar notch (NWI≤0.2) were selected for reconstructing the 3D model of the knee and simulating the intercondylar notch plasty. Then, the volume of osteotomy in 3D model was calculated and applied in the ACL reconstruction surgery, and whether the graft had impingement with intercondylar notch or not was evaluated. Results There were significant differences in NW and CW between male group and female group (P≤lt;≤0.05), but no significant difference was found in the NWI (P≤gt;≤0.05). And there was no significant difference in NW, CW, and NWI between the left and right knees both in male group and female group (P≤gt;≤0.05). After ACL reconstruction and intercondylar notchplasty, the shape of intercondylar notch became normal (NWI≤gt;≤0.22), no impingement occurred between the graft and intercondylar notch under arthroscopy within 3-month follow-up. Conclusion The shape of intercondylar notch of 3D model based on MRI 2D images is similar to the real intercondylar notch. NWI is one of important indexes which can reflect the narrow level of intercondylar notch. The virtual intercondylar notchplasty may provide preoperative plan and guidence for ACL reconstruction operation to avoid the impingement between graft and intercondylar notch after surgery.
ObjectiveTo establish an rabbit model of early steroid-induced avascular necrosis of the femoral head (SANFH) and evaluate its validity with MRI and pathological examination.
MethodsTwenty 6-month-old rabbits (weighing, 2-3 kg) were randomly divided into 2 groups (control group and model group), 10 rabbits in each group. Dexamethasone sodium phosphate solution (10 mg/kg) was injected into bilateral gluteus in model group, and the same amount of saline was injected in control group, every 3 days for 14 times. General observation was done after modelling. Osteonecrosis was verified by pathological observation and MRI findings at 6 weeks.
ResultsAfter 6 weeks, rabbits did not show obvious changes in control group; increased hair removal, decreased food intake, and slight limp were observed in model group. The MRI results showed normal shape of the bilateral femoral head and no abnormal signals in control group; irregular shape of the bilateral femoral head and a slice of irregular abnormal signals were observed, and necrosis and cystolization of the subchondral bone and sparse changes of trabecular bone were shown in model group. General observation from coronal section of femoral head showed smooth red cartilage surface in control group; on the contrary, the cartilage surface of the femoral head became dull, thin even visible hemorrhage under articular cartilage and necrosis of the femoral head were observed. The histopathological examination indicated that trabecular bone of the femoral head in control group was massive, thick, and close, and osteocytes in the bone lacunae had normal shapes. The osseous trabecular became thinner and broken; karyopyknosis of osteocytes and bone empty lacunae could be obviously seen in model group. The rates of empty lacunae were 8.0%±0.5% in control group and 49.0%±0.3% in model group, showing significant difference (t=21.940, P=0.000).
ConclusionEstablishing a model of early SANFH through injecting shortterm, shock, and high dose of dexamethasone, and it can been evaluated effectively with MRI and pathological examination.
Objective To investigate the diagnosis and effectiveness of surgical treatment for lumbar pyogenic spondyl itis. Methods Between February 2005 and June 2010, 15 cases of lumbar pyogenic spondyl itis were treated. There were 10 males and 5 females with an average age of 48.6 years (range, 26-72 years). Affected segments included L2, 3 in 3 cases,L3, 4 in 3 cases, L4, 5 in 8 cases, and L5, S1 in 1 case. All cases had cl inical manifestations of moderate or severe fever, local pain of lesion, and l imitation of the spinal movement; 10 patients had nerve root symptoms, and 8 patients had symptoms of lower limb paraplegia. Leukocyte, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) significantly increased in all cases. The preoperative X-ray and CT examinations showed no clear bone destruction; MRI showed decreased signal intensity on T1WI and increased signal intensity on T2WI, 7 cases had local ized abscess formation. The patients underwent focal cleaning and bone grafting and fusion combined with internal fixation, including anterior operation in 13 cases, posterior operation in 1 case, and combined anterior and posterior operation in 1 case. The results of bacterial culture were positive in 10 cases. According to the results of intraoperative bacterial cultures, sensitive antibiotics were selected. Results Healing of incision by first intention was achieved in 14 cases, healing by second intention in 1 case. After 2 weeks, 1 case recurred and symptoms was rel iefed after symptomatic treatment. Back pain and (or) lower limb pain were obviously improved in the other patients; body temperature recovered to normal after 3-4 days; leukocyte, ESR, and CRP significantly decreased. All the patients were followed up 12 to 70 months with an average of 35.4 months.The patients had no rejection, no fistula formation, no lumbar kyphosis, and no fixator loosening or breakage. The bony fusion time was 4-8 months. Conclusion Combination of cl inical manifestations, laboratory tests, and MRI can diagnose lumbar pyogenic spondyl itis, of which CRP is an important indicator to determine progression of the disease, and MRI is important for diagnosis. Debridement combined with interbody fusion and internal fixation is a safe and effective treatment method.
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.
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
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.
Objective To explore the diagnosis and treatment of anterior cruciate l igament (ACL) cysts of the knees. Methods The cl inical data were retrospectively analysed from 13 patients with ACL cysts between December 2000 and August 2007. The patients included 7 males and 6 females with an average age of 46.3 years (range, 32-55 years). The locationswere the left knee in 6 cases and the right knee in 7 cases. Seven cases had an obvious history of trauma, 4 cases had a history of chronic injury, and 2 cases had no obvious incentive factor. The disease duration was from 6 to 29 months (mean, 20 months). Anterior drawer test was positive in 1 case, pivot shift test was positive in 1 case, and McMurray test was positive in 3 cases. Six cases were preoperatively diagnosed by MRI. The cysts located near the tibial insertion in 6 cases, between the ACL and the posterior cruciate l igament in 3 cases, and near the femoral attachment in 4 cases. All cysts were arthroscopically resected and had the pathohistological examination. Results The pathohistological examination showed mucoid degeneration of collagen and connective tissues, and the diagnosis result was ACL cyst. All incisions healed by first intention, and no compl ication occurred. Thirteen patients were followed up 2 to 5 years (mean, 2 years and 6 months). The symptoms of arthralgia, swell ing, and interlocking of the affected knees disappeared. At 24 months postoperatively, the anterior drawer test was positive in 1 case, the pivot shift test was positive in 1 case, and McMurray test was positive in 4 cases. There was no recurrence during the follow-up. There were significant differences in the range of motion and Lysholm score between pre- and post-operation (P lt; 0.01). Conclusion ACL cysts may be indicated by simple knee pain, especially when accompanied by l imitation of joint motion without imaging evidence of osteoarthritis. The MRI finding is very important in the diagnosis of ACL cysts, and arthroscopic resection and debridement is the first choice in the treatment of ACL cysts.
Objective To evaluate the value of MRI and MDCT in detecting both inferior vena cava tumor thrombus and vena cava wall invasion in renal cell carcinoma. Methods Databases including PubMed, EMbase, The Cochrane Library, MEDLINE (Ovid), CBM, CNKI, VIP and WanFang Data were searched from January 2000 to February 2012. Relevant studies were screened on the basis of the inclusion and exclusion criteria, and then quality assessment and data extraction were conducted. Then heterogeneity test and meta-analysis were conducted using RevMan 5 and Meta-disc 1.4. Results A total of 6 trials involving 244 patients and 246 cases of renal cell carcinoma were included. The results of meta-analysis showed that, for the MRI group and the MDCT group, the sensitivity was 0.963 and 0.952, the specificity was 0.969 and 0.979, the value of +LR was 9.759 and 15.57, the value of ?LR was 0.091 and 0.108, and the dOR was 198.71 and 251.54, respectively. There were no significant differences in pooled effect-size among groups (Pgt;0.05). The area under curve (AUC) of summary ROC curve analysis as well as Q index of the MDCT group were 0.981 8 and 0.940 7, respectively. Conclusion There is no significant difference in the value of MRI and MDCT in detecting inferior vena cava tumor thrombus induced by renal cell carcinoma. More original studies on vena cava wall invasion by tumor thrombus should be conducted in the future due to the limitation of current materials.
