Standardized quantitative measurements of wrist cartilage in healthy humans using 3T magnetic resonance imaging

AIM: To quantify the wrist cartilage cross-sectional area in humans from a 3D magnetic resonance imaging(MRI) dataset and to assess the corresponding reproducibility. METHODS: The study was conducted in 14 healthy volunteers(6 females and 8 males) between 30 and 58 years old and devoid of articular pain. Subjectswere asked to lie down in the supine position with the right hand positioned above the pelvic region on top of a home-built rigid platform attached to the scanner bed. The wrist was wrapped with a flexible surface coil. MRI investigations were performed at 3T(Verio-Siemens) using volume interpolated breath hold examination(VIBE) and dual echo steady state(DESS) MRI sequences. Cartilage cross sectional area(CSA) was measured on a slice of interest selected from a 3D dataset of the entire carpus and metacarpalphalangeal areas on the basis of anatomical criteria using conventional image processing radiology software. Cartilage cross-sectional areas between opposite bones in the carpal region were manually selected and quantified using a thresholding method.RESULTS: Cartilage CSA measurements performed on a selected predefined slice were 292.4 ± 39 mm2 using the VIBE sequence and slightly lower, 270.4 ± 50.6 mm2, with the DESS sequence. The inter(14.1%) and intra(2.4%) subject variability was similar for both MRI methods. The coefficients of variation computed for the repeated measurements were also comparable for the VIBE(2.4%) and the DESS(4.8%) sequences. The carpus length averaged over the group was 37.5 ± 2.8 mm with a 7.45% between-subjects coefficient of variation. Of note, wrist cartilage CSA measured with either the VIBE or the DESS sequences was linearly related to the carpal bone length. The variability between subjects was significantly reduced to 8.4% when the CSA was normalized with respect to the carpal bone length.CONCLUSION: The ratio between wrist cartilage CSA and carpal bone length is a highly reproducible standardized measurement which normalizes the natural diversity between individuals.

Optimization of hepatobiliary phase delay time of Gd-EOB-DTPA-enhanced magnetic resonance imaging for identification of hepatocellular carcinoma in patients with cirrhosis of different degrees of severity

AIM To optimize the hepatobiliary phase delay time(HBPDT) of Gd-EOB-DTPA-enhanced magnetic resonance imaging(GED-MRI) for more efficient identification of hepatocellular carcinoma(HCC) occurring in different degrees of cirrhosis assessed by Child-Pugh(CP) score.METHODS The liver parenchyma signal intensity(LPSI), the liver parenchyma(LP)/HCC signal ratios, and the visibility of HCC at HBP-DT of 5, 10, 15, 20, and 25 min(i.e., DT-5, DT-10, DT-15, DT-20, and DT-25) after injection of GdEOB-DTPA were collected and analyzed in 73 patients with cirrhosis of different degrees of severity(including 42 patients suffering from HCC) and 18 healthy adult controls.RESULTS The LPSI increased with HBP-DT more significantly in the healthy group than in the cirrhosis group(F = 17.361, P < 0.001). The LP/HCC signal ratios had a significant difference(F = 12.453, P < 0.001) among various HBP-DT points, as well as between CP-A and CP-B/C subgroups(F = 9.761, P < 0.001). The constituent ratios of HCC foci identified as obvious hypointensity(+++), moderate hypointensity(++), and mild hypointensity or isointensity(+/-) kept stable from DT-10 to DT-25: 90.6%, 9.4%, and 0.0% in the CP-A subgroup; 50.0%, 50.0%, and 0.0% in the CP-B subgroup; and 0.0%, 0.0%, and 100.0% in the CP-C subgroup, respectively.CONCLUSION The severity of liver cirrhosis has significant negative influence on the HCC visualization by GED-MRI. DT-10 is more efficient and practical than other HBP-DT points to identify most of HCC foci emerging in CP-A cirrhosis, as well as in CP-B cirrhosis; but an HBP-DT of 15 min or longer seems more appropriate than DT-10 for visualization of HCC in patients with CP-C cirrhosis.

Clinical applications of advanced magnetic resonance imaging techniques for arthritis evaluation

Magnetic resonance imaging(MRI) has allowed a comprehensive evaluation of articular disease, increasing the detection of early cartilage involvement, bone erosions, and edema in soft tissue and bone marrow compared to other imaging techniques. In the era of functional imaging, new advanced MRI sequences are being successfully applied for articular evaluation in cases of inflammatory, infectious, and degenerative arthropathies. Diffusion weighted imaging, new fat suppression techniques such as DIXON, dynamic contrast enhanced-MRI, and specific T2 mapping cartilage sequences allow a better understanding of the physiopathological processes that underlie these different arthropathies. They provide valuable quantitative information that aids in their differentiation and can be used as potential biomarkers of articular disease course and treatment response.

Reversible lesions in the brain parenchyma in Wilson's disease confirmed by magnetic resonance imaging:earlier administration of chelating therapy can reduce the damage to the brain

The aim of this study was to evaluate the resolution of brain lesions in patients with Wilson’s disease during the long-term chelating therapy using magnetic resonance imaging and a possible signiifcance of the time latency between the initial symptoms of the disease and the introduction of this therapy. Initial magnetic resonance examination was performed in 37 patients with proven neurological form of Wilson’s disease with cerebellar, parkinsonian and dystonic presentation. Magnetic resonance reexamination was done 5.7 ± 1.3 years later in 14 patients. Patients were divided into： group A, where chelating therapy was initiated 〈 24 months from the ifrst symp-toms and group B, where the therapy started≥ 24 months after the initial symptoms. Symmetry of the lesions was seen in 100% of patients. There was a signiifcant difference between groups A and B regarding complete resolution of brain stem and putaminal lesions （P= 0.005 andP=0.024, respectively）. If the correct diagnosis and adequate treatment are not established less than 24 months after onset of the symptoms, irreversible lesions in the brain parenchyma could be ex-pected. Signal abnormalities on magnetic resonance imaging might therefore, at least in the early stages, represent reversible myelinolisis or cytotoxic edema associated with copper toxicity.

Spectrum of intracranial incidental findings on pediatric brain magnetic resonance imaging:What clinician should know?

Intracranial incidental findings on magnetic resonance imaging(MRI) of the brain continue to generate interest in healthy control,research,and clinical subjects.However,in clinical practice,the discovery of incidental findings acts as a "distractor".This review is based on existing heterogeneous reports,their clinical implications,and how the results of incidental findings influence clinical management.This draws attention to the followings:(1) the prevalence of clinically significant incidental findings is low;(2) there is a lack of a systematic approach to classification;and discusses(3) how to deal with the detected incidental findings based a proposed common clinical profile.Individualized neurological care requires an active discussion regarding the need for neuroimaging.Clinical significance of incidental findings should be decided based on lesion's neuroradiologic characteristics in the given clinical context.Available evidence suggests that the outcome of an incidentally found "serious lesion in children" is excellent.Future studies of intracranial incidental findings on pediatric brain MRI should be focused on a homogeneous population.The study should address this clinical knowledge based review powered by the statistical analyses.

In Vitro Targeted Magnetic Delivery and Tracking of Superparamagnetic Iron Oxide Particles Labeled Stem Cells for Articular Cartilage Defect Repair

To assess a novel cell manipulation technique of tissue engineering with respect to its ability to augment superparamagnetic iron oxide particles （SPIO） labeled mesenchymal stem cells （MSCs） density at a localized cartilage defect site in an in vitro phantom by applying magnetic force. Meanwhile, non-invasive imaging techniques were use to track SPIO-labeled MSCs by magnetic resonance imaging （MRI）. Human bone marrow MSCs were cultured and labeled with SPIO. Fresh degenerated human osteochondral fragments were obtained during total knee arthroplasty and a cartilage defect was created at the center. Then, the osteochondral fragments were attached to the sidewalls of culture flasks filled with phosphate-buffered saline （PBS） to mimic the human joint cavity. The SPIO-labeled MSCs were injected into the culture flasks in the presence of a 0.57 Tesla （T） magnetic force. Before and 90 min after cell targeting, the specimens underwent T2-weighted turbo spin-echo （SET2WI） sequence of 3.0 T MRI. MRI results were compared with histological findings. Macroscopic observation showed that SPIO-labeled MSCs were steered to the target region of cartilage defect. MRI revealed significant changes in signal intensity （P0.01）. HE staining exibited that a great number of MSCs formed a three-dimensional （3D） cell ＂sheet＂ structure at the chondral defect site. It was concluded that 0.57 T magnetic force permits spatial delivery of magnetically labeled MSCs to the target region in vitro. High-field MRI can serve as an very sensitive non-invasive technique for the visualization of SPIO-labeled MSCs.

Ultra-high-field magnetic resonance:Why and when?

This paper briefly summarizes the development of magnetic resonance imaging and spectroscopy in medicine.Aspects of magnetic resonancephysics and-technology relevant at ultra-high magnetic fields as well as current limitations are highlighted.Based on the first promising studies,potential clinical applications at 7 Tesla are suggested.Other aims are to stimulate awareness of the potential of ultra-high field magnetic resonance and to stimulate active participation in much needed basic or clinical research at 7 Tesla or higher.

Detection of Repair of the Zone of Calcified Cartilage with Osteoarthritis through Mesenchymal Stem Cells by Ultrashort Echo Time Magnetic Resonance Imaging

Objective：Currently,magnetic resonance imaging （MRI） is the most commonly used imaging modality for observing the growth and development of mesenchymal stem cells （MSCs） after in vivo transplantation to treat osteoarthritis （OA）.However,it is a challenge to accurately monitor the treatment effects of MSCs in the zone of calcified cartilage （ZCC） with OA.This is especially true in the physiological and biochemical views that are not accurately detected by MRI contrast agents.In contrast,ultrashort time echo （UTE） MRI has been shown to be sensitive to the presence of the ZCC,creating the potential for more effectively observing the repair of the ZCC in OA by MSCs.A special focus is given to the outlook of the use ofUTE MRI to detect repair of the ZCC with OA through MSCs.The limitations of the current techniques for clinical applications and future directions are also discussed.Data Sources：Using the combined keywords：＂osteoarthritis＂,＂mesenchymal stem cells＂,＂calcified cartilage＂,and ＂magnetic resonance imaging＂,the PubMed/MEDLINE literature search was conducted up to June 1,2017.Study Selection：A total of 132 published articles were initially identified citations.Of the 132 articles,48 articles were selected after further detailed review.This study referred to all the important English literature in full.Results：In contrast,UTE MRI has been shown to be sensitive to the presence of the ZCC,creating the potential for more effectively observing the repair of the ZCC in OA by MSCs.Conclusions：The current studies showed that the ZCC could be described in terms of its histomorphology and biochemistry by UTE MRI.We prospected that UTE MRI has been shown the potential for more effectively observing the repair of the ZCC in OA by MSCs in vivo.

Magnetic resonance imaging for non-invasive clinical evaluation of normal and regenerated cartilage

With the development of tissue engineering and regenerative medicine,it is much desired to establish bioimaging techniques to monitor the real-time regeneration efficacy in vivo in a non-invasive way.Herein,we tried magnetic resonance imaging(MRI)to evaluate knee cartilage regeneration after implanting a biomaterial scaffold seeded with chondrocytes,namely,matrix-induced autologous chondrocyte implantation(MACI).After summary of the T2 mapping and the T1-related delayed gadolinium-enhanced MRI imaging of cartilage(dGEMRIC)in vitro and in vivo in the literature,these two MRI techniques were tried clinically.In this study,18 patients were followed up for 1 year.It was found that there was a significant difference between the regeneration site and the neighboring normal site(control),and the difference gradually diminished with regeneration time up to 1 year according to both the quantitative T1 and T2 MRI methods.We further established the correlation between the quantitative evaluation of MRI and the clinical Lysholm scores for the first time.Hence,the MRI technique was confirmed to be a feasible semiquantitative yet non-invasive way to evaluate the in vivo regeneration of knee articular cartilage.

Reproducibility and accuracy of quantitative assessment of articular cartilage volume measurements with 3.0 tesla magnetic resonance imaging

Background Quantitative magnetic resonance imaging （qMRI） of articular cartilage represents a powerful tool in osteoarthritis research, but has so far been confined to a field strength of 1.5 T. The aim of the study was to determine the reproducibility and accuracy of qMRI assessments of the knee cartilage volume by comparing quantitative swine cartilage volumes of the sagittal （sag） multi echo data imagine combination water-excitation （MEDICwe） sequence and the fast low-angle shoot water-excitation （FLASHwe） sequence at 3.0-T MRI to directly measured volumes （DMV） of the surgically removed articular cartilage.Methods Test-retest MRI was acquired in 20 swine knees. Two sag FLASHwe sequences and two sag MEDICwe sequences （spatial resolution 0.4 mm × 0.4 mm × 1.0 mm of 3-dimension （3D） were acquired at 3-T MRI in a knee.Articular cartilage volume was calculated from 3D reformations of the MRI by using a manual program. Calculated volumes were compared with DMV of the surgically removed articular cartilage. Knee joint cartilage plates were quantified paired in order.Results In the knee joint of swine, reproducibility errors （paired analysis） for cartilage volume were 2.5% to 3.2% with sag FLASHwe, and 1.6% to 3.0% with sag MEDICwe. Correlation coefficients between results obtained with qMRI and DMV ranged from 0.90 to 0.98 for cartilage volume. Systematic pairwise difference between results obtained with qMRI and DMV ranged from -1.1% to 2.8%. Random pairwise differences between results obtained with qMRI and DMV ranged from （2.9 ±2.4）% to （6.8±4.5）%.Conclusions FLASHwe and MEDICwe sequences permit highly accurate and reproducible analysis of cartilage volume in the knee joints of swine at 3-T MRI. Cartilage volume reproducibility for the MEDICwe data is slightly higher than the FLASHwe data.

Gadolinium-hyaluronic acid nanoparticles as an efficient and safe magnetic resonance imaging contrast agent for articular cartilage injury detection

Accurate detection of cartilage injuries is critical for their proper treatment because these injuries lack the selfhealing ability and lead to joint dysfunction.However,the low longitudinal T1 relaxivity(r1)and non-specificity of contrast agents(such as gadolinium(III)-diethylenetriamine-pentaacetic acid(Gd-DTPA))significantly limit the efficiency of clinical magnetic resonance imaging(MRI)applications.To overcome these drawbacks,we integrated hyaluronic acid(HA)with Gd to synthesize a Gd-DTPA-HA composite,which was subsequently freeze-dried to produce nanoparticles(NPs).The resultant Gd-HA NPs demonstrated a greater r1 value(12.51 mM^-1 s^-1)compared with the bulk Gd-DTPA-HA(8.37 mM^-1 s^-1)and clinically used Gd-DTPA(3.88 mM^-1 s^-1).Moreover,the high affinity of HA to the cartilage allowed these NPs to penetrate deeper beyond the cartilage surface.As a result,Gd-HA NPs considerably increased the quality of cartilage and lesion MR images via their intra-articular injection in vivo.Specifically,2 h after NP administration,the signal-to-noise ratio at the injured cartilage site was 2.3 times greater than the value measured before the injection.In addition,Gd-HA NPs exhibited good biosafety properties due to the absence of adverse effects in the blood or on the main organs.It was also showed that Gd NPs were first metabolized by the kidney and liver and then excreted from the body with urine.Thus,Gd-HA NPs can potentially serve as an efficient MRI contrast agent for improved detection of cartilage injuries.

T1ρ/T2 mapping and histopathology of degenerative cartilage in advanced knee osteoarthritis

AIM To investigate whether normal thickness cartilage in osteoarthritic knees demonstrate depletion of proteoglycan or collagen content compared to healthy knees.METHODS Magnetic resonance(MR) images were acquired from5 subjects scheduled for total knee arthroplasty(TKA)(mean age 70 years) and 20 young healthy control subjects without knee pain(mean age 28.9 years). MR images of T1ρ mapping, T2 mapping, and fat suppressed proton-density weighted sequences were obtained.Following TKA each condyle was divided into 4 parts(distal medial, posterior medial, distal lateral, posterior lateral) for cartilage analysis. Twenty specimens(bone and cartilage blocks) were examined. For each joint,the degree and extent of cartilage destruction was determined using the Osteoarthritis Research Society International cartilage histopathology assessment system.In magnetic resonance imaging(MRI) analysis, 2 readers performed cartilage segmentation for T1ρ/T2 values and cartilage thickness measurement.RESULTS Eleven areas in MRI including normal or near normal cartilage thickness were selected. The corresponding histopathological sections demonstrated mild to moderate osteoarthritis(OA). There was no significant difference in cartilage thickness in MRI between control and advanced OA samples [medial distal condyle, P = 0.461;medial posterior condyle(MPC), P = 0.352; lateral distal condyle, P = 0.654; lateral posterior condyle, P = 0.550],suggesting arthritic specimens were morphologically similar to normal or early staged degenerative cartilage.Cartilage T2 and T1ρ values from the MPC were significantly higher among the patients with advanced OA(P= 0.043). For remaining condylar samples there was no statistical difference in T2 and T1ρ values between cases and controls but there was a trend towards higher values in advanced OA patients. CONCLUSION Though cartilage is morphologically normal or near normal, degenerative changes exist in advanced OA patients. These changes can be detected with T2 and T1ρ MRI techniques.

Diagnosing, planning and evaluating osteochondral ankle defects with imaging modalities

This current concepts review outlines the role of diffe-rent imaging modalities in the diagnosis, preoperative planning, and follow-up of osteochondral ankle defects. An osteochondral ankle defect involves the articular cartilage and subchondral bone(usually of the talus) and is mostly caused by an ankle supination trauma. Conventional radiographs are useful as an initial imaging tool in the diagnostic process, but have only moderate sensitivity for the detection of osteochondral defects. Computed tomography(CT) and magnetic resonance imaging(MRI) are more accurate imaging modalities. Recently, ultrasonography and single photon emission CT have been described for the evaluation of osteochondral talar defects. CT is the most valuable modality for assessing the exact location and size of bony lesions. Cartilage and subchondral bone damage can be visualized using MRI, but the defect size tends to be overestimated due to bone edema. CT with the ankle in full plantar flexion has been shown a reliable tool for preoperative planning of the surgical approach. Postoperative imaging is useful for objective assessment of repair tissue or degenerative changes of the ankle joint. Plain radiography, CT and MRI have been used in outcome studies, and different scoring systems are available.

Morphological MRI and T2 mapping of cartilage repair tissue after mosaicplasty with tissue-engineered cartilage in a pig model

The aim of this study was to evaluate the efficacy of mosaicplasty with tissue-engineered cartilage for the treatment of osteochondral defects in a pig model with advanced MR technique. Eight adolescent miniature pigs were used. The right knee underwent mosaicplasty with tissue-engineered cartilage for treatment of focal osteochondral defects, while the left knee was repaired via single mosaicplasty as controls. At 6, 12, 18 and 26 weeks after surgery, repair tissue was evaluated by magnetic resonance imaging （MRI） with the cartilage repair tissue （MOCART） scoring system and T2 mapping. Then, the results of MRI for 26 weeks were compared with findings of macroscopic and histologic studies. The MOCART scores showed that the repaired tissue of the tissue-engineered cartilage group was statistically better than that of controls （P 〈 0.001）. A significant correlation was found between macroscopic and MOCART scores （P 〈 0.001）. Comparable mean T2 values were found between adjacent cartilage and repair tissue in the experimental group （P 〉 0.05）. For zonal T2 value evaluation, there were no significant zonal T2 differences for repair tissue in controls （P 〉 0.05）. For the experimental group, zonal T2 variation was found in repair tissue （P 〈 0.05）. MRI, macroscopy and histology showed better repair results and bony incorporation in mosaicplasty with the tissue-engi- neered cartilage group than those of the single mosaicplasty group. Mosaicplasty with the tissue-engineered cartilage is a promising approach to repair osteochodndral defects. Morphological MRI and T2 mapping provide a non-invasive method for monitoring the maturation and integration of cartilage repair tissue in vivo.

Evaluation of Knees in Asymptomatic Amateur Ice Hockey Players Using 3.0-T Magnetic Resonance Imaging：A Case-Control Study

Background：Research on the changes to knee structures in asymptomatic amateur ice hockey players （AAIHPs） has been limited.We aimed to assess the performance of the knees in AAIHPs using 3.0-T magnetic resonance imaging （MRI）.Methods：A total of 71 asymptomatic knees （32 AAIHPs and 39 age-and sex-matched controls） were imaged using a 3.0-T MRI scanner at the Affiliated Zhongshan Hospital of Dalian University in April 2017.Two experienced musculoskeletal radiologists were blinded to assess all MRI findings,including bursae around the knee,bone marrow edema （BME）,meniscal signal changes,and articular cartilage and ligament damage.Any disagreements were resolved by a third professor of musculoskeletal radiology.Categorical variables were compared using the Chi-square test and continuous variables using the Student＇s t-test or Mann-Whitney U-test.Results：The most common finding was fluid-filled bursae surrounding the knee.In the AAIHP group,which totaled 32 knees and 416 bursae,155 （37％） fluid-filled bursae were present.In the control group,there were a total of 39 knees and 507 bursae,and 91（18％） fluid-filled bursae were present.There was a significant difference in the number of fluid-filled bursae between the two groups （P ＜ 0.05）.However,in AAIHPs,the prevalence of meniscal signal changes （16 knees,50％） was higher than in the control group （2 knees,5％;P ＜ 0.001）.Importantly,15 of the 19 were grade Ⅱ signals.Other changes were only found in AAIHPs.Articular cartilage lesions were detected in 47％ of their knees,predominantly at the patellofemoral joint,and BME was found in 34％ of their knees.Conclusion：The MRI findings of knees in AAIHPs mainly manifested as self-protection reaction,and proper ice hockey exercise could be advocated.

Repair of a large patellar cartilage defect using human umbilical cord blood-derived mesenchymal stem cells:A case report

BACKGROUND Patellar dislocation may cause cartilage defects of various sizes.Large defects commonly require surgical treatment;however,conventional treatments are problematic.CASE SUMMARY A 15-year-old male with a large patellar cartilage defect due to patellar dislocation was treated via human umbilical cord blood-derived mesenchymal stem cell(hUCB-MSC)implantation.To our knowledge,this is the first report of this treatment for this purpose.The patient recovered well as indicated by good visual analog scale,International Knee Documentation Committee and McMaster Universities Osteoarthritis Index scores.Magnetic resonance imaging showed cartilage regeneration 18 mo postoperatively.CONCLUSION Umbilical cord blood-derived hUCB-MSCs may be a useful treatment option for the repair of large patellar cartilage defects.

Non-invasive MRI assessment of the articular cartilage in clinical studies and experimental settings

Attrition and eventual loss of articular cartilage are important elements in the pathophysiology of osteoarthritis(OA).Preventing the breakdown of cartilage is believed to be critical to preserve the functional integrity of a joint.Chondral injuries are also common in the knee joint,and many patients benefit from cartilage repair.Magnetic resonance imaging(MRI) and advanced digital post-processing techniques have opened possibilities for in vivo analysis of cartilage morphology,structure,and function in healthy and diseased knee joints.Techniques of semi-quantitative scoring of human knee cartilage pathology and quantitative assessment of human cartilage have been developed.Cartilage thickness and volume have been quantified in humans as well as in small animals.MRI detected cartilage loss has been shown to be more sensitive than radiographs detecting joint space narrowing.It is possible to longitudinally study knee cartilage morphology with enough accuracy to follow the disease-caused changes and also evaluate the therapeutic effects of chondro-protective drugs.There are also several MRI methods that may allow evaluation of the glycosaminoglycan matrix or collagen network of articular car-tilage,and may be more sensitive for the detection of early changes.The clinical relevance of these methods is being validated.With the development of new therapies for OA and cartilage injury,MR images will play an important role in the diagnosis,staging,and evaluation of the effectiveness of these therapies.

Myocardial fibrosis detection in arrhythmogenic right ventricular dysplasia/cardiomyopathy by 3. 0T magnetic resonance imaging

Arrhythmogenic right ventricular dysplasia/cardiomyopathy (ARVD/C) is characterized by fibro-fatty replacement of the right ventricle.However,the feasibility and significance of myocardial fibrosis detec-ted by delayed enhancement (DE) using 3.0T magnetic resonance imaging (MRI) in.ARVD /C is seldomly studied.Methods Twenty-seven consecutive patients were prospectively evaluated for ARVD /C.Magnetic reso-nance imaging was performed on a 3.0T scanner.Ten minutes after intravenous administration of 0.2 mmol /kg of gadodiamide,DE-MRI was obtained.Diagnosis of ARVD /C was based upon the Task Force criteria and in-cluded MRI findings.Results Seventeen(59% ) of 27 patients met the Task Force criteria for ARVD /C.Right ven-tricle DE was found in all (100% ) ARVD /C patients compared with none (0%) of the 10 patients without ARVD /C (P <0.001) .Additional left ventricular DE was found in 8/17 ARVD/C patients while without left ventricular mor-phological and functional abnormalities detected by echocardiography or MRI.Conclusions DE using 3.0T MRI could effectively detect myocardial fibrosis in the right and left ventricular myocardium in ARVD /C patients.Detection of myocardial fibrosis may have an important clinical significance in ARVD/C diagnosis.Histological left ventricle in-volvement may be easily missed by echocardiography.

MRI T_2 star mapping、T_1 images与3D DESS融合图在隐匿性膝关节软骨损伤中的应用

目的探讨T_2 star mapping、T_1 images与3D DESS融合伪彩图在关节软骨损伤中的诊断价值。方法对26例关节软骨损伤患者行T_2 star mapping、T_1 images和3D DESS扫描,并将T_1 images、T_2 star mapping与3D DESS图像融合,评价患者股骨、胫骨、髌骨关节软骨损伤程度并与关节镜结果对比,计算融合伪彩图诊断软骨损伤的特异性、敏感性及与关节镜诊断结果一致性。结果 T_1 images-3D DESS融合伪彩图诊断关节软骨损伤的敏感度、特异度及Kappa值分别为92.8%、93.0%、0.769,T_2 star mapping-3D DESS融合伪彩图诊断关节软骨损伤的敏感度、特异度及Kappa值分别为91.4%、94.2%、0.787。结论 T_2 star mapping、T_1 images与3D DESS融合伪彩图在关节软骨早期损伤评价上优于关节镜。

磁共振成像对儿童急性创伤性髌骨外侧脱位后膝关节韧带及骨软骨损伤的特点分析

目的:基于磁共振成像(MRI)分析儿童急性创伤性髌骨外侧脱位后膝关节韧带、骨软骨损伤特点。方法:回顾性分析2020年9月至2023年9月期间唐山市第二医院收治的126例急性创伤性髌骨外侧脱位患儿的临床资料,所有患儿均接受膝关节MRI扫描,按损伤程度分为部分撕裂组(85例)和完全撕裂组(41例)。分析两组患儿内侧髌股韧带(MPFL)损伤、骨软骨损伤的位置和特点。结果:126例患儿均伴有MPFL损伤,其中部分撕裂85例,完全撕裂41例。部分撕裂中单纯髌骨侧34例,单纯股骨侧14例,单纯发中间段9例,多部位损伤28例;完全撕裂组中单纯发生于髌骨侧27例,单纯股骨侧7例,单纯中间段4例,多部位损伤3例。MPFL部分撕裂组与完全撕裂组的单纯髌骨侧和多部位损伤比较,差异有统计学意义(χ^(2)=7.596、10.886,P<0.05)。126例患儿中,91例合并股内斜肌(VMO)损伤,VMO损伤程度与MPFL损伤程度呈正相关(r=0.339,P=0.006)。126例患儿中有119例存在骨软骨损伤,共有损伤部位174个。VMO损伤中,1级损伤的部位以单纯髌骨侧为主,2、3、4级损伤的以多发损伤为主。结论:儿童急性创伤性髌骨外侧脱位多伴有MPFL损伤和骨软骨损伤,且以髌骨侧多发性损伤为主;损伤部位和程度无性别差异;MPFL损伤多合并VMO损伤,且损伤程度与MPFL呈正相关。