Dual-energy CT virtual non-calcium: an accurate method for detection of knee osteoarthritis-related edema-like marrow signal intensity.

OBJECTIVES: To evaluate the performance of a dual-energy computed tomography (DECT) virtual non-calcium (VNCa) technique in the detection of edema-like marrow signal intensity (ELMSI) in patients with knee joint osteoarthritis (OA) compared to magnetic resonance imaging (MRI). METHODS: The study received local ethics board approval, and written informed consent was obtained. DECT and MRI were used to examine 28 knees in 24 patients with OA. VNCa images were generated by dual-energy subtraction of calcium. The knee joint was divided into 15 regions for ELMSI grading, performed independently by two musculoskeletal radiologists, with MRI as the reference standard. We also analyzed CT numbers through receiver operating characteristics and calculated cut-off values. RESULTS: For the qualitative analysis, we obtained CT sensitivity (Readers 1, 2 = 83.7%, 89.8%), specificity (Readers 1, 2 = 99.5%, 99.5%), positive predictive value (Readers 1, 2 = 95.3%, 95.7%), and negative predictive value (Readers 1, 2 = 97.9%, 98.7%) for ELMSI. The interobserver agreement was excellent (κ = 0.92). The area under the curve for Reader 1 and Reader 2 was 0.961 (95% CI 0.93, 0.99) and 0.992 (95% CI 0.98, 1.00), respectively. CT numbers obtained from the VNCa images were significantly different between regions with and without ELMSI (p < .001). CONCLUSIONS: VNCa images have good diagnostic performance for the qualitative and quantitative analysis of knee osteoarthritis-related ELMSI.

Assessment of structural brain changes in patients with type 2 diabetes mellitus using the MRI-based brain atrophy and lesion index.

Patients with type 2 diabetes mellitus (T2DM) often have cognitive impairment and structural brain abnormalities. The magnetic resonance imaging (MRI)-based brain atrophy and lesion index can be used to evaluate common brain changes and their correlation with cognitive function, and can therefore also be used to reflect whole-brain structural changes related to T2DM. A total of 136 participants (64 men and 72 women, aged 55-86 years) were recruited for our study between January 2014 and December 2016. All participants underwent MRI and Mini-Mental State Examination assessment (including 42 healthy control, 38 T2DM without cognitive impairment, 26 with cognitive impairment but without T2DM, and 30 T2DM with cognitive impairment participants). The total and sub-category brain atrophy and lesion index scores in patients with T2DM with cognitive impairment were higher than those in healthy controls. Differences in the brain atrophy and lesion index of gray matter lesions and subcortical dilated perivascular spaces were found between non-T2DM patients with cognitive impairment and patients with T2DM and cognitive impairment. After adjusting for age, the brain atrophy and lesion index retained its capacity to identify patients with T2DM with cognitive impairment. These findings suggest that the brain atrophy and lesion index, based on T1-weighted and T2-weighted imaging, is of clinical value for identifying patients with T2DM and cognitive impairment. Gray matter lesions and subcortical dilated perivascular spaces may be potential diagnostic markers of T2DM that is complicated by cognitive impairment. This study was approved by the Medical Ethics Committee of University of South China (approval No. USC20131109003) on November 9, 2013, and was retrospectively registered with the Chinese Clinical Trial Registry (registration No. ChiCTR1900024150) on June 27, 2019.

Anatomic study of carpal tunnel in adults using monoenergetic reconstruction of dual-energy computed tomography.

OBJECTIVE: To seek optimal keV settings for imaging carpal tunnel in adults by dual-energy computed tomography (DECT) monoenergetic technique; to describe anatomic characteristics of carpal tunnel and to observe correlation between carpal bony and soft tissue structures. METHODS: DECT images of 20 wrists (11 left and 9 right wrists; 14 men, mean age 26.93±1.38 years, range 23 to 28, and 6 women, mean age 24.17 ± 0.98 years, range 23 to 26) were evaluated. Monoenergetic images were reconstructed at 42, 62, 82, 102, 122, and 142 keV. Image quality was assessed along a 5-point Likert scale, and the highest-quality images were chosen for quantitative analysis. Two musculoskeletal radiologists performed both analyses independently. RESULTS: The optimal energy spectrum with the best contrast-to-noise ratio (CNR) for monoenergetic images were at 62 keV (19 wrists, 95%) and 61 keV (1 wrist, 5%). There was substantial interobserver agreement between the readers in the 5-point Likert scale analysis of image quality (k= 0.793). Bland-Altman plots also indicated good agreement between observers in quantitative analysis. Intra-category 1 and 2 correlation was mostly discovered at hamate hook level and middle level of pisiform (P < 0.05), while bony and soft tissue structures partly reached correlation (P < 0.05). CONCLUSIONS: The optimal energy spectrum for monoenergetic DECT imaging of carpal tunnel structures was 62 keV. DECT monoenergetic imaging could predict changes in soft tissue structures and demonstrate carpal tunnel anatomic structures.

Reliability and Validity of Abdominal Skeletal Muscle Area Measurement Using Magnetic Resonance Imaging.

RATIONALE AND OBJECTIVES: Skeletal muscle mass measurement is the most important element for diagnosing sarcopenia. MRI has an excellent soft-tissue contrast, which can non-invasively assess abdominal skeletal muscle area (SMA) as well as CT. This study aimed to assess the validity and reliability of abdominal SMA measurement by comparing CT and MRI based on the fat image of IDEAL-IQ sequence at the lumbar level mid-L3. MATERIALS AND METHODS: CT and MRI images of 32 patients diagnosed with various kidney diseases were used to analyze intra-observer variability among abdominal SMA measurements. This was done to evaluate the correlation of SMA between CT and fat images of MRI. SMA images were segmented using Materialise Mimics software before quantification. Interobserver reliability and validation of measurements was evaluated by two independent investigators. Abdominal SMA reproducibility and correlation between CT and MRI were then assessed using the intraclass correlation coefficient (ICC), coefficient of variation (CV), Bland-Altman plot, and Pearson's correlation coefficient respectively. RESULTS: The interobserver reliability of MRI was excellent. The CV value was 2.82% while the ICC values ranged between 0.996 and 0.999. Validity was high (CV was 1.7% and ICC ranged between 0.986 and 0.996) for measurements by MRI and CT. Bland Altman analysis revealed an average difference of 2.2% between MRI and CT. The Pearson's correlation coefficient was 0.995 (p < 0.0001). This result revealed that there was a strong correlation between the two technologies. CONCLUSION: MRI exhibited good interobserver reliability and excellent agreement with CT for quantification of abdominal SMA.

Effects of Dandelion Extract on the Proliferation of Rat Skeletal Muscle Cells and the Inhibition of a Lipopolysaccharide-Induced Inflammatory Reaction.

BACKGROUND: Dandelion is commonly used in traditional Chinese medicine with several active compounds found in extracts. It has a variety of pharmacological effects, such as a reduction in swelling and inflammation, and detoxification. The mechanism by which dandelion extract inhibits the inflammatory response in skeletal muscle cells remains unknown; therefore, the aim of this study was to investigate the effects of dandelion extract root on the proliferation of skeletal muscle cells and the alleviation of lipopolysaccharide (LPS)-induced inflammatory response in vitro. METHODS: Rat skeletal muscle cells were isolated from Sprague-Dawley rat and cultured in vitro which were cultured in basal medium, or medium containing LPS or dandelion extract. Cell counting kit-8 (CCK-8) was employed to measure cell proliferation; meanwhile, the optimal concentration of dandelion extract and treatment time were selected. Crystal violet staining was used to detect the proliferation of muscle cells. Western blotting analysis was used to detect the levels of inflammatory factors, myogenic factor, and p-AKT protein expression. RESULTS: The optimal concentration and treatment time of dandelion extract for the following study were 5 mg/ml and 4 days, respectively. Dandelion extract was found to increase proliferation of rat skeletal muscle cells (t = 3.145, P < 0.05), with the highest effect observed at 5 mg/ml. LPS was found to decrease proliferation of skeletal muscle cells (t = -131.959, P < 0.001), and dandelion extract could against this affection (t = 19.466, P < 0.01). LPS could induce expression of inflammatory factors, including interleukin (IL)-1ß, IL-6 and tumor necrosis factor (TNF)-α (IL-1ß: t = 9.118, P < 0.01; IL-6: t = 4.346, P < 0.05; TNF-α: t = 15.806, P < 0.05), and dandelion extract was shown to reduce LPS-induced expression of IL-1ß, IL-6 and TNF-α (IL-1ß: t = -2.823, P < 0.05; IL-6: t = -3.348, P < 0.01; and TNF-α: t = -3.710, P < 0.01). Furthermore, LPS was also shown to decrease expression of myogenic factor, including myod1 and myogenin (MyoD1: t = 4.039, P < 0.05 and myogenin: t = 3.300, P < 0.01), but dandelion extract was shown to against this effect of LPS (MyoD1: t = -3.160, P < 0.05 and myogenin: t = -3.207, P < 0.01). And then, LPS was found to increase expression of p-AKT protein (p-AKT/AKT: t = 4.432, P < 0.05). Moreover, expression of p-AKT protein was found to decrease, with 5 mg/ml of dandelion extract (p-AKT/AKT: t = -3.618, P < 0.05). CONCLUSIONS: The findings indicate that dandelion extract plays an important role in skeletal muscle cells viability regulation, promote cells proliferation by increasing level of p-AKT protein expression, and reduce LPS-induced expression of inflammatory factors, inhibiting the inflammatory response of rat skeletal muscle cells.

Comparison Thigh Skeletal Muscles between Snowboarding Halfpipe Athletes and Healthy Volunteers Using Quantitative Multi-Parameter Magnetic Resonance Imaging at Rest.

BACKGROUND: Magnetic resonance (MR) imaging provides a unique, noninvasive diagnostic platform to quantify the physiological and biochemical variables of skeletal muscle at rest. This study was to investigate the difference in thigh skeletal muscles between snowboarding halfpipe athletes and healthy volunteers via multiparametric MR imaging. METHODS: A comparative study was conducted between 12 healthy volunteers and 14 snowboarding halfpipe athletes. MR scanning targeted the left leg at the level of the proximal thigh on a 3.0T MR system. The measured parameters compared between the two groups included T1, T2, T2* relaxation times, fat fraction (FF), and cross-sectional area (CSA) of the quadriceps femoris and the hamstring muscles. Statistical analysis was carried out using independent sample t-test. Interrater reliability was also assessed with intraclass correlation coefficients (ICCs). RESULTS: It was statistically equivalent between two groups in age, body mass index, thigh circumference, calf circumference, systolic blood pressure, and resting heart rate (all P > 0.05). However, the T1 and T2 values of the hamstring muscles in the athlete group were found to be significantly shorter than those in control group (T1: 1063.3 ± 24.1 ms vs. 1112.0 ± 38.2 ms in biceps femoris, 1050.4 ± 31.2 ms vs. 1095.0 ± 39.5 ms in semitendinosus, 1053.1 ± 31.7 ms vs. 1118.4 ± 40.0 ms in semimembranosus, respectively; T2: 33.4 ± 0.7 ms vs. 36.1 ± 1.9 ms in biceps femoris, 34.6 ± 2.0 ms vs. 37.0 ± 1.9 ms in semitendinosus, 36.9 ± 1.5 ms vs. 38.9 ± 2.4 ms in semimembranosus, respectively; all P < 0.05) although T2* relaxation time was detected with no significant difference. The FF of the hamstring muscles was obviously less than the control group (5.5 ± 1.9% vs. 10.7 ± 4.7%, P < 0.001). In addition, the quadriceps' CSA in the athlete group was substantially larger than the control group (8039.0 ± 1072.3 vs. 6258.2 ± 852.0 mm2, P < 0.001). Interrater reliability was excellent (ICC: 0.758-0.994). CONCLUSION: Multiple MR imaging parameters indicated significant differences between snowboarding halfpipe athletes and healthy volunteers in the thigh skeletal muscles.

Efficacy and safety of continuous radiofrequency thermocoagulation plus pulsed radiofrequency for treatment of V1 trigeminal neuralgia: A prospective cohort study.

Patients may develop serious eye complications after continuous radiofrequency thermocoagulation (CRF) for V1 (ophthalmic division) trigeminal neuralgia (TN) at a higher temperature. Therefore, the temperature of clinical CRF for V1 TN has long been disputed, but there have few reports been found about how to achieve satisfactory pain relief, reduce the incidence rates of complications, and shorten the recovery time after CRF for V1 TN.To observe whether pulsed radiofrequency (PRF) can lead to increased rate in pain relief, reduced rate of complications, or shortened recovery time after CRF is used to treat V1 idiopathic trigeminal neuralgia (ITN).The prospective cohort study enrolled 56 patients with V1 ITN from May 2012 to April 2015. The patients were randomized into 2 treatment groups as follows: CRF only (group A, n = 28) and CRF plus PRF (group B, n = 28). The patients were followed 3 years up for pain relief, complications, and health-related quality of life (HRQoL).All the patients in either group achieved satisfactory pain relief at discharge. After treatment, patients completely pain free in group A and group B accounted for 81.6%, 92.0% at 1 year, 68.4%, 92.0% at 2 years, and 68.4%, 83.6% at 3 years, respectively. The pain relief rate was higher in group B patients than in group A, but the difference was not statistically significant. During the follow-up period, 9 (32.1%) patients in group A and 2 (7.1%) patients in group B developed recurrence (P < 0.05). Eleven patients in group A occurred corneal hypoesthesia and with recovery time was 11.9 ±â€Š7.5 (4-18) months versus 3 patients in group B with recovery time was 3.4 ±â€Š2.5 (2-6) months, the differences of incidence rate and recovery times were all significant (P < 0.05) between groups A and B. The mean scores of HRQoL in group B patients were higher than that in group A patients (P < 0.05).PRF after CRF results in decreased recurrence of V1 TN, reduced numbers of corneal hypoesthesia, shortened recovery time, and increased HRQoL scores. Its clinical use is recommended.

Treatment of bilateral idiopathic trigeminal neuralgia by radiofrequency thermocoagulation at different temperatures.

Radiofrequency thermocoagulation (RFT) is an effective treatment for trigeminal neuralgia, but consensus regarding an optimal treatment temperature is lacking. While treatment temperatures ranging from 60°C to 95°C have been reported, RFT at too high a temperature is often followed by serious complications, and comparative evaluations of RFT at different temperatures in a single study are rare.This current prospective cohort study was to compare immediate and long-term outcomes of RFT at varying temperatures in patients with bilateral idiopathic trigeminal neuralgia (ITN) of maxillary division of trigeminal nerve (V2), mandibular division of trigeminal nerve (V3), and V2+V3, including pain relief, complications, recurrence rate, and patient satisfaction. From May 2011 to April 2016, 62 consecutive patients with bilateral ITN of V2, V3, and V2+V3 were enrolled in the study. These patients underwent bilateral RFT at 68°C and 75°C, respectively, using the same RF parameters. Side-to-side results, including pain relief, complications, and patient satisfaction, were compared during a 5-year follow-up period.Overall pain relief was satisfactory after RFT. The rate of pain relief after treatment at 75°C was slightly higher than at 68°C (P > 0.05). The pain-free rate was 95.1% at 75°C and 93.5% at 68°C at 1 year, 84.3% and 78.1% at 3 years, and 80.7% and 74.4% at 5 years. There were 10 and 13 cases of recurrence, respectively, and 6 cases of bilateral recurrence. The incidence and severity of complications were greater at 75°C (P < 0.05) than at 68°C, and therefore the patient satisfaction at the higher temperature was lower (P < 0.05).Patients with bilateral ITN who underwent RFT at different temperatures had consistent pain relief after RFT at both 75°C and 68°C, but there were fewer and less severe complications at 68°C, which was accompanied by greater patient satisfaction. This suggests that RFT at lower temperatures may be preferable, and that a temperature of 68°C can be recommended.

Association between open or closed reduction and avascular necrosis in developmental dysplasia of the hip: A PRISMA-compliant meta-analysis of observational studies.

BACKGROUND: The risk of avascular necrosis of the femoral head (AVN) after treatment of developmental dysplasia of the hip is associated with the method of reduction. Some authors have suggested that open reduction is a risk factor for AVN; however, this is controversial. To our knowledge, a quantitative comparison of the incidence of AVN between closed and open reduction has not been conducted. METHODS: Published studies were identified by searching PubMed, EMBASE, and the Cochrane Library up to May, 2015, focusing on the incidence of AVN after closed or open reduction for developmental dysplasia of the hip in children aged <3 years. Patients were age-matched who were treated by either closed or open reduction, but without pelvic or femoral osteotomy. Two authors independently assessed eligibility and abstracted data. Discrepancies were discussed and resolved by consensus. We pooled the odds ratios (ORs) and 95% confidence intervals (95%CIs) from individual studies using a random-effects model and evaluated heterogeneity and publication bias. RESULTS: Nine retrospective studies were included in this analysis. The pooled OR for comparing open reduction with closed reduction for all grades of AVN was 2.26 (95%CI = 1.21-4.22), with moderate heterogeneity (I = 44.7%, P = 0.107). The pooled OR for grades II to IV AVN was 2.46 (95%CI = 0.93-6.51), with high heterogeneity (I = 69.6%, P = 0.003). A significant association was also found for the further surgery between open and closed reduction, with a pooled OR of 0.30 (95%CI = 0.15-0.60) and moderate heterogeneity (I = 46.4%, P = 0.133). No evidence of publication bias or significant heterogeneity between subgroups was detected by meta-regression analyses. CONCLUSION: Findings from this meta-analysis suggest that open reduction is a risk factor for the development of AVN compared with closed treatment. Future studies are warranted to investigate how open reduction combined with pelvis and/or femoral osteotomy affects the incidence of AVN.

Magnetic Resonance Three-dimensional Cube Technique in the Measurement of Piglet Femoral Anteversion.

BACKGROUND: The accurate measurement of the femoral anteversion (FA) angle is always a topic of much debate in the orthopedic surgery and radiology research. We aimed to explore a new FA measurement method to acquire accurate results without radiation damage using piglet model. METHODS: A total of thirty piglets were assigned to two groups based on the age. Bilateral femora were imaged with 3.0-T magnetic resonance (MR) and 64-slice computed tomography (CT) examinations on all piglets. FA was measured on MR-three-dimensional (3D) postprocessing software with a four-step method: initial validation of the femoral condylar axis, validation of the condylar plane, validation of the femoral neck axis, and line-plane angle measurement of FA. After MR and CT examinations, all piglets were sacrificed and their degree of FA was measured using their excised, dried femora. MR, CT, and dried-femur measurement results were analyzed statistically; MR and CT measurements were compared for accuracy against each other and against the gold standard dried femur measurement. RESULTS: In both groups, the mean FA value measured by MR was lower than that measured by CT. A statistically significant difference was observed between CT- and dried-femur measurements but not between MR- and dried-femur measurements. A higher correlation (0.783 vs. 0.408) and a higher consistency (0.863 vs. 0.578) with dried-femur measurement results were seen for MR measurements than CT measurements in the 1-week age group. However, in the 8-week age group, similar correlations (0.707 vs. 0.669) and consistencies (0.864 vs. 0.821) were observed. CONCLUSIONS: Noninvasive MR-3D-Cube reconstruction was able to accurately measure FA in piglets. Particularly in the 1-week age group with a larger proportion of cartilaginous structures, the correlation and consistency between MR- and dried-femur measurement results were higher than those between CT- and dried-femur measurements, suggesting that MR may be a new useful examination tool for FA-related diseases in children.

Radiofrequency thermocoagulation for V2/V3 idiopathic trigeminal neuralgia: effect of treatment temperatures on long-term clinical outcomes: A Cohort Study.

Radiofrequency thermocoagulation (RFT) is widely used to treat trigeminal neuralgia (TN); however, the optimal temperature at which RFT is most efficacious remains under much debate. Thus, the aim of the present study was to determine the lowest temperature at which morbidity could be minimized and patient outcomes maximized.A multivariate analysis was used to study 1354 patients who underwent computed tomography (CT)-guided RFT for V2/V3 idiopathic trigeminal neuralgia (ITN) during from June 2006 to May 2015. RFT was carried out at 62, 65, and 68°C, while keeping all other RF parameters the same. This was a prospective cohort study, in which we assessed intra- and postoperative complications, pain relief, and long-term health-related quality of life (HRQoL).The intraoperative and in-hospital complications of patients were mainly facial hematoma, mouth and external auditory meatus penetration, nausea, vomiting, dizziness, and headache, which were all treated symptomatically. In long-term follow-up, patients with pain relief (defined as no pain and no required drug intervention) at 62, 65, and 68°C accounted for 94.2%, 98.3%, and 98.8% (at discharge); 83.8%, 90.1%, and 91.4% (at 1 year); 66.7%, 80.5%, and 88.2% (at 3 years); 59.0%, 64.3%, and 77.2% (at 5 years); 48.7%, 57.8%, and 72.3% (at 7 years); 40.6%, 53.7%, and 60.3% (at 9 years), respectively. The number of patients with facial numbness, masticatory atonia, or corneal hypoesthesia was increased with the elevation of temperature, but these complications were all mild. No blindness, deafness, intracranial hemorrhage, or death as a result of the surgical intervention occurred in any patients. SF-36 scores showed highest HRQoL in the group treated at 68°C, followed by the 65 and 62°C groups, respectively.Our results demonstrate that 68°C is a good choice for RFT of V2/V3 ITN. The alternative option is 65 or 62°C for RFT to minimize the occurrence of complications including facial numbness, yet which often yields a higher recurrence rate.

Effect of gene polymorphism of COMT and OPRM1 on the preoperative pain sensitivity in patients with cancer.

OBJECTIVES: To evaluate the effect of COMT and OPRM1 gene polymorphisms on the preoperative pain sensitivity in tumor patients. METHODS: 300 cases of cancer patients undergoing elective surgery were included, and the Val158 Met loci of COMT gene and OPRM1 loci of A118 G gene were genotyped by PCR-RFLP. Pain threshold and pain tolerance threshold were measured using electrical stimulation to investigate the preoperative pain sensitivity in patients with different genotypes. RESULTS: For the COMT gene, the pain threshold and pain tolerance threshold of patients with M allele both decreased (both P < 0.001); for PPRM1 gene, pain threshold and pain tolerance threshold of patients with G allele decreased (both P < 0.001). We also found that there was an interaction between the two genes. CONCLUSION: Gene polymorphisms of COMT and OPRM1 were correlated with the preoperative pain sensitivity of cancer patients. The patients with M allele of COMT and G allele of OPRM1 had higher preoperative pain sensitivity.

Regulatory network of differentially expressed genes in metastatic osteosarcoma.

The present study aimed to investigate the possible molecular mechanisms underlying the pathogenesis of metastatic osteosarcoma (OS), by examining the microarray expression profiles of normal samples, and metastatic and non­metastatic OS samples. The GSE9508 gene expression profile was downloaded from the Gene Expression Omnibus database, which included 11 human metastatic OS samples, seven non­metastatic OS samples and five normal samples. Pretreatment of the data was performed using the BioConductor package in R language, and the differentially expressed genes (DEGs) were identified by a t­test. Furthermore, function and pathway enrichment analyses of the DEGs were conducted using a molecule annotation system. A differential co­expression network was also constructed, and the submodules were screened using MCODE in Cytoscape. A total of 965 genes were identified as DEGs in metastatic OS. The DEGs were shown to participate in the regulation of DNA­dependent transcription, the composition of the nucleus, cytoplasm and membrane, and protein and nucleotide binding. Furthermore, the screened DEGs were significantly associated with the ribosome, axon guidance and the cytokine­cytokine receptor interaction pathway. Certain hub genes were identified in the constructed differential co­expression network, including matrix metalloproteinase 1 (MMP1), smoothened (SMO), ewing sarcoma breakpoint region 1 (EWSR1) and fasciculation and elongation protein ζ­1 (FEZ1). Brain selective kinase 2 (BRSK2) and aldo­keto reductase family 1 member B10 (AKRIB10) were present in the screened submodules. The results of the present study suggest that genes, including MMP1, SMO, EWSR1, FEZ1, BRSK2 and AKRIB10, may be potential targets for the diagnosis and treatment of metastatic OS.

Normal cranial bone marrow MR imaging pattern with age-related ADC value distribution.

OBJECTIVE: To determine MRI appearances of normal age-related cranial bone marrow and the relationship between MRI patterns and apparent diffusion coefficient (ADC) values. METHODS: Five hundred subjects were divided into seven groups based on ages. Cranial bone marrow MRI patterns were performed based on different thickness of the diploe and signal intensity distribution characteristics. ADC values of the frontal, parietal, occipital and temporal bones on DWI were measured and calculated. Correlations between ages and ADC values, between patterns and ADC values, as well as the distribution of ADC values were analyzed. RESULTS: Normal cranial bone marrow was divided into four types and six subtypes, Type I, II, III and IV, which had positive correlation with age increasing (χ2=266.36, P<0.01). The ADC values of normal parietal and occipital bone marrow showed significant negative correlation with age growing (r=-0.561 and -0.622, P<0.01), while there were no significant differences of that with age increasing in frontal and temporal bone marrow (P>0.05). In addition, there was significant negative correlation between the ADC values and MRI patterns in the normal parietal and occipital bones (r=-0.691 and -0.750, P<0.01). CONCLUSION: The combination of MRI features and ADC values changes in different cranial bones showed significant correlation with age increasing. Familiar with the MRI appearance of the normal bone marrow conversion pattern in different age group and their ADC value will aid the diagnosis and differential of the cranial bone pathology.

[Evaluation of mid-term follow-up after Salter innominate osteotomy in developmental dysplasia of the hip].

OBJECTIVES: To evaluate the mid-term outcome after Salter innominate osteotomy in developmental dysplasia of the hip (DDH), and to observe the developmental characteristics of the hip after operation and the relationships between the mid-term outcome and radiographic parameters as well as age at operation. METHODS: : Forty-four patients with 61 treated hips were selected. The patients were treated with Salter innominate osteotomy and followed-up for at least three years with intact serial radiographs. Radiographs taken before operation, 6 weeks, 1 year and 2 - 3 years after operation and in the latest follow-up were selected. Acetabular index (AI), Sharp acetabular angle (SAA) and center-edge angle of Wiberg (CEA) were measured and Severin classification was done according to radiographs taken in the latest follow-up. RESULTS: The average correction of AI was 14° postoperatively. The acetabulum remodels best at 2-3 years after operation when the average AI became very close to normal. In the latest follow-up the SAA was 41° which could be regarded as normal. Postoperative CEA was on average 23° which increased to 25° 2-3 years later. In the latest follow-up, the average CEA was 26°. The ratio of excellent and good outcomes (Severin I, II) was 84%, while the ratio of moderate and poor outcomes (Severin III, IV, V, VI) was 16%. Age at operation had a negative effect on outcomes. Although 70% patients operated after age 6 had satisfactory outcomes. The Severin I, II group showed no difference in AI from III, IV, V, VI group 6 weeks after operation, but the AI of the former obviously improved 2-3 years after operation while that of the latter deteriorated. Significant difference in SAA and the CEA could be observed in the latest follow-up. CONCLUSIONS: Salter innominate osteotomy focuses on normalizing the abnormal acetabular direction in DDH children as well as stimulating the remodeling of the acetabulum, which provides a satisfactory middle-term outcome. The acetabulum remodels rapidly during the first three years after operation when AI and CEA develops into normal. Interference should be adopted if these changes have not appeared in the first three years.