Reliability and sensitivity to change of IW-TSE versus DESS magnetic resonance imaging sequences in the assessment of bone marrow lesions in knee osteoarthritis patients: Longitudinal data from the Osteoarthritis Initiative (OAI) cohort

Background: Bone marrow lesions (BMLs) are associated with osteoarthritis (OA). We assessed the performance of two commonly used MRI sequences, IW-TSE and DESS, for reliability in the detection of BMLs and sensitivity to estimate change over time. We suggested that the IW-TSE would demonstrate higher sensitivity to change than DESS in the assessment of BML prevalence and change over time. This study was performed using a subset of the Osteoarthritis Initiative (OAI) cohort. Methods: A sub-group of 144 patients was selected from the OAI progression cohort who all had IW-TSE and DESS MRI acquisitions at baseline and 24 months. BMLs were assessed using a semi-quantitative scale in the global knee, medial and lateral compartments, and subregions. Intra-reader reliability was assessed on a subset of 51 patients. Results: Intra-reader reliability was substantial for the global knee ≥ 0.64, medial ≥ 0.70, and lateral ≥ 0.63 compartments for IW-TSE and DESS. The prevalence of BML detected at baseline was only slightly greater for IW-TSE compared to DESS. The mean BML score at baseline was significantly higher (p ≤ 0.006) for the IW-TSE than the DESS. However, mean change at 24 months was similar for both sequences for all regions except the medial compartment (p = 0.034) and medial femur (p = 0.015) where they were significantly higher for DESS than IW-TSE. Moreover, the prevalence of BML change at 24 months was similar in all regions except the global knee (p = 0.047) and the lateral tibial plateau (p = 0.031). Conclusion: This study does not suggest superior sensitivity to change of one sequence over the other for almost all the regions. The only difference is a higher BML mean change over time detected by the DESS sequence in the medial compartment and femur. These data bring into perspective that both sequences seem equivalent regarding their use for the assessment of BML in clinical trials.

Machine‐learning radiomics to predict bone marrow metastasis of neuroblastoma using magnetic resonance imaging

Background: Neuroblastoma is one common pediatric malignancy notorious forhigh temporal and spatial heterogeneities. More than half of its patients developdistant metastases involving vascularized organs, especially the bone marrow. It isthus necessary to have an economical, noninvasive method without muchradiation for follow‐ups. Radiomics has been used in many cancers to assistaccurate diagnosis but not yet in bone marrow metastasis in neuroblastoma.Methods: A total of 182 patients with neuroblastoma were retrospectivelycollected and randomly divided into the training and validation sets. Fivehundredand seventy‐two radiomics features were extracted from magneticresonance imaging, among which 41 significant ones were selected via T‐testfor model development. We attempted 13 machine‐learning algorithms andeventually chose three best‐performed models. The integrative performanceevaluations are based on the area under the curves (AUCs), calibration curves,risk deciles plots, and other indexes.Results: Extreme gradient boosting, random forest (RF), and adaptiveboosting were the top three to predict bone marrow metastases in neuroblastoma while RF was the most accurate one. Its AUC was 0.90(0.86–0.93), F1 score was 0.82, sensitivity was 0.76, and negative predictivevalue was 0.79 in the training set. The values were 0.82 (0.71–0.93), 0.80,0.75, and 0.92 in the validation set, respectively.Conclusions: Radiomics models are likely to contribute more to metastaticdiagnoses and the formulation of personalized healthcare strategies in clinics.It has great potential of being a revolutionary method to replace traditionalinterventions in the future.

Histological Findings of Bone Marrow Lesions on Magnetic Resonance Images in Patients with Varus Knee Osteoarthritis

Bone marrow lesions (BMLs) on magnetic resonance (MR) images in knee osteoarthritis patients are considered to predict the severity and progression of the disease. We evaluated the histological findings of BMLs on MR images of the subchondral area of the medial femoral condyle in varus osteoarthritic knees. In 24 patients with varus knee osteoarthritis who underwent total knee arthroplasty (TKA), sagittal T1- and T2-weighted MR images of the affected knee were acquired before TKA. During TKA, resected bone pieces from the distal medial femoral condyle were obtained. Sagittal specimens obtained from the center of the bone pieces were histologically examined. Twenty patients had BMLs. Histological findings of BMLs in the subchondral area showed various features, such as fibrovascular tissue, cyst formation, active bone remodeling with bone formation and bone resorption, and hyaline cartilage. BMLs were not found in four patients;histological findings of these patients showed normal bone marrow tissue with normal-thickness trabeculae. Subchondral bony end plate in knees with BMLs was usually thin or destroyed, while that without BMLs was thick or normal. The condition of the subchondral bony end plate would explain the differences in the severity and progression between patients with or without BMLs.

Tumor infiltration of bone marrow in patients with hemato-logical malignancies: dynamic contrast-enhanced magnetic resonance imaging

Background Conventional magnetic resonance （MR） scanning techniques can identify bone marrow （BM） containing mostly fat cells. But they are not able to differentiate BM tumor infiltration, BM fibrosis and normal red BM. This is particularly problematic in assessment of recurrent or refractory hematological malignancy. This pilot study used dynamic contrast-enhanced MR imaging （DCE-MRI） to evaluate the bone marrow status and to determine whether several calculated parameters derived from the DCE-MRI correlate with histological characteristics of marrow, especially with the tumor fraction （TF）. Methods DCE-MRI scans were performed in 25 patients with proven or known hematological malignancy who were about to undergo bone marrow biopsy of the posterior iliac crest. The location chosen for biopsy was examined with MRI approximately one hour prior to the biopsy. Time-signal intensity curves （TIC） were generated from the region of the iliac crest corresponding to the planned biopsy site. Enhancement parameters were calculated, including peak enhancement ratio （PER）, maximum enhancement slope （S1opemax）, time to peak （TTP） and mean time （MT）. The biopsy specimen was reported synoptically, with relevant reported parameters including cellularity and tumor fraction （TF）. Results PER values were significantly higher for the bone marrow tumor infiltration group than for the normal bone marrow group （P〈0.05）. A significant positive correlation was found between PER and TF as well as S1opemax and TF. A negative correlation was found between TTP and TF. There was no significant difference in the mean TTP and MT values between the BM tumor infiltration group and the normal bone marrow group. Conclusions The presence of diffuse bone marrow infiltration in patients with haematological malignancies could be verified using DCE-MRI.

AGE-RELATED CHANGES OF BONE MARROW OF NORMAL ADULT MAN ON DIFFUSION WEIGHTED IMAGING

Objective To investigate the signal intensity and apparent diffusion coefficient (ADC) of bone marrow of normal adult man on diffusion weighted imaging (DWI). Methods Fifteen healthy volunteers and thirty-eight patients with benign prostatic hyperplasia or normal prostate were enrolled in this study, with age range 28-82 years old (mean 55.26 ± 18.05 years). All people were examined with large field DWI on a 3.0T magnetic resonance scanner, which ranges from the top of head to the lower limb. The signal-to-noise ratio (SNR) on the DWI and ADC of lumber vertebra at renal hilum level, left ilium and superior segment of left femur were measured. The measured SNR and ADC value of the above sites were compared by one way analysis of variance and their correlations with age were investigated by Pearson's correlation analysis. Results The SNR of lumber vertebra, left ilium and left femur showed no significant difference (F = 0.271, P = 0.763). The SNR of lumber vertebra (r = 0.309, P = 0.024) and left ilium (r = 0.359, P = 0.008) showed positive correlation with age, while the SNR of left femur showed no correlation with age (r = -0.163, P = 0.283). The ADC of lumber vertebra [(0.617 ± 0.177) ×10-3 mm2/s] was significantly higher than that of left ilium [(0.404 ± 0.112) ×10-3 mm2/s, P < 0.001] and left femur [(0.362 ± 0.092) ×10-3 mm2/s, P < 0.001], while the ADC of left ilium and left femur had no significant difference. The ADC of lumber vertebra, left ilium and left femur showed no correlation with age. Conclusion Understanding of age-related changes of normal adult bone marrow on DWI is very important to differentiate the normal bone marrow and abnormal lesions.

visual bone marrow mesenchymal stem cell transplantation in the repair of spinal cord injury

An important factor in improving functional recovery from spinal cord injury using stem cells is maximizing the number of transplanted cells at the lesion site. Here, we established a contusion model of spinal cord injury by dropping a weight onto the spinal cord at T7_8. Superparamagnet- ic iron oxide-labeled bone marrow mesenchymal stem cells were transplanted into the injured spinal cord via the subarachnoid space. An outer magnetic field was used to successfully guide the labeled cells to the lesion site. Prussian blue staining showed that more bone marrow mesen- chymal stem cells reached the lesion site in these rats than in those without magnetic guidance or snperparamagnetic iron oxide labeling, and immunofluorescence revealed a greater number of complete axons at the lesion site. Moreover, the Basso, Beattie and Bresnahan （BBB） locomotor rating scale scores were the highest in rats with superparamagnetic labeling and magnetic guid- ance. Our data confirm that superparamagnetic iron oxide nanoparticles effectively label bone marrow mesenchymal stem cells and impart sufficient magnetism to respond to the external magnetic field guides. More importantly, superparamagnetic iron oxide-labeled bone marrow mesenchymal stem cells can be dynamically and non-invasively tracked in vivo using magnetic resonance imaging. Superparamagnetic iron oxide labeling of bone marrow mesenchymal stem cells coupled with magnetic guidance offers a promising avenue for the clinical treatment of spinal cord injury.

Feridex-labeled bone marrow stromal cells for analysis of sciatic nerve defects in rabbits

BACKGROUND： Traumatic approaches, such as sacrifice and perfusion sampling, have been used to evaluate efficiency of stem cell transplantation. However, these methods are not applicable to human studies. Cell tracing, in combination with non-invasive imaging technology, can be utilized to trace cell survival following transplantation to evaluate the efficacy of cell transplantation therapy. OBJECTIVE： To explore feasibility of magnetic resonance imaging （MRI） to observe in vivo repair of injured sciatic nerves following feridex and polylysine （FE-PLL） complex-labeled bone marrow stromal cell （BMSC） transplantation. DESIGN, TIME AND SE＇I-rlNG： A randomized, controlled, animal experiment was performed at the Laboratory of the Department of Neurosurgery, Zhujiang Hospital from March to December 2008. MATERIALS： Feridex was purchased from Advanced Magnetic, USA, and polylysine was purchased from Sigma, USA. METHODS： BMSCs were harvested from adult rabbit femurs and were cultured in vitro with neural stem cell culture medium, leukemia inhibitory factor, and basic fibroblast growth factor. Bone marrow stromal cell-derived neural stem cells （BMSC-D-NSCs） were obtained and labeled with FE-PLL complex. The right sciatic nerve （0.8 mm） was excised from healthy, New Zealand rabbits, aged 1.5 months, and the epineuria of distal stumps underwent turnover and were anastomosed at the proximal ends. FE-PLL labeled BMSC-D-NSC suspension or culture medium was transplanted into the epineunal lumen using a microsyringe. The left sciatic nerve was left intact and sewed as the normal control. MAIN OUTCOME MEASURES： Cellular morphology, proliferation, and differentiation, as well as expression of nestin and neuron-specific enolase （NSE）, of BMSCs-D-NSCs were observed. Efficacy of FE-PLL labeling and effects on cells were measured. In addition, neural regeneration at 2, 8, and 16 weeks following transplantation was observed by MRI. Histopathology and mean number of regenerated nerve fibers in the proximodistal-injured sciatic nerve were evaluated by hematoxylin and eosin and Bielschowsky staining. RESULTS： Results demonstrated that BMSCs expanded, proliferated, and differentiated into neural-like cells with slim, long processes. The cells expressed nestin and NSE, as detected by immunocytochemistry. BMSC-D-NSCs were effectively labeled by FE-PLL, with a labeling efficiency of 98%. In addition, cell viability was not influenced by the FE-PLL complex. MRI results revealed low signals in the FE-labeled BMSC-D-NSC-implanted region of the sciatic nerve. A low-signal region was observed at 2 weeks, which was widely spread at 8-16 weeks after cell transplantation. The regenerated nerve fibers were orderly arranged in the cell transplantation group and exhibited no significant differences compared with the normal control side （P 〉 0.05）. CONCLUSION： BMSCs were successfully cultured in vitro, and the cells proliferated and trans-differentiated into neuronal-like cells, which expressed nestin and NSE. The FE-PLL complex effectively labeled rabbit BMSC-D-NSCs in vitro and did not affect peripheral neural regeneration following cell transplantation. Results demonstrated that MRI could be used to track FE-labeled BMSC-D-NSCs transplanted in the sciatic nerve.

Inhibitory effects of cytosine deaminase gene-transfected bone marrow mesenchymal stem cells on glioma cell proliferation

Bone marrow mesenchymal stem cells were isolated from C57BL mice, transfected with the cytosine deaminase （CD） gene using a lentivirus vector and co-cultured with C6 glioma cells to verify anti-tumor effects of bone marrow mesenchymal stem cells carrying CD genes. C57MSC-CD/eGFP cells converted 5-fluorocytosine to 5-fluorouracil and exhibited significant inhibition of proliferation and apoptosis in C6 glioma cells. C57MSC-CD/eGFP cells were then implanted into rat models of brain C6 glioma. Rats were also intraperitoneally injected with 5-fluorocytosine after 7 days. MSC-CD/eGFP cells were irregularly distributed at the margin of the glioma, as well as encased and reduced the volume of the glioma. CD-transfected bone marrow mesenchymal stem cells inhibit the in vivo growth and in vitro proliferation of glioma.

Magnetic resonance imaging of the spinal marrow:Basic understanding of the normal marrow pattern and its variant

For now, magnetic resonance (MR) is the best noninvasive imaging modality to evaluate vertebral bone marrow thanks to its inherent soft-tissue contrast and non-ionizing nature. A daily challenging scenario for every radiologist interpreting MR of the vertebral column is discerning the diseased from normal marrow. This requires the radiologist to be acquainted with the used MR techniques to judge the spinal marrow as well as its normal MR variants. Conventional sequences used basically to image marrow include T1W, fat-suppressed T2W and short tau inversion recovery (STIR) imaging provides gross morphological data. Interestingly, using non-routine MR sequences; such as opposed phase, diffusion weighted, MR spectroscopy and contrasted-enhanced imaging; may elucidate the nature of bone marrow heterogeneities; by inferring cellular and chemical composition; and adding new functional prospects. Recalling the normal composition of bone marrow elements and the physiologic processes of spinal marrow conversion and reconversion eases basic understanding of spinal marrow imaging. Additionally, orientation with some common variants seen during spinal marrow MR imaging as hemangiomas and bone islands is a must. Moreover, awareness of the age-associated bone marrow changes as well as changes accompanying different variations of the subject&#x02019;s health state is essential for radiologists to avoid overrating normal MR marrow patterns as pathologic states and metigate unnecessary further work-up.

基于MRI定量非对称回波最小二乘估算水脂分离技术的成人腰椎骨髓脂肪与年龄和性别的相关性研究

目的:基于MRI定量非对称回波最小二乘估算水脂分离(iterative decomposition of water and fat with echo asymmetry and least-squares estimation image quantitation,IDEAL-IQ)技术探讨成年人腰椎不同节段骨髓脂肪与年龄和性别的关系。方法:收集298例受检者的MRI IDEAL-IQ脂肪分数图像,其中男性138例,女性160例,年龄20~69岁。将所有患者按照每10岁为一个年龄段分为5组:20~29岁(20~组),男24例,女20例;30~39岁(30~组),男47例,女39例;40~49岁(40~组),男36例,女47例;50~59岁(50~组),男20例,女37例;60~69岁(60~组),男11例,女17例。使用脂肪分数图在GE ADW4.6工作站测量L1~L5的骨髓质子密度脂肪分数(proton density fat fraction,PDFF)。结果:同一年龄组、不同性别间PDFF存在差异,20~、30~、40~组人群中,男性L1~L5椎体PDFF均高于女性(P<0.05);50~组人群中男性L1~L5椎体PDFF与女性的差异无统计学意义(P>0.05);60~组人群,男性L1~L5椎体PDFF均低于女性(P<0.05)。腰椎椎体PDFF与年龄呈正相关,女性(r=0.72,P<0.05)相关性高于男性(r=0.32,P<0.05)。从20~69岁,男性L4 PDFF增长率最大(21.08%),女性L1 PDFF增长率最大(65.68%);男性各椎体PDFF增长主要集中在30~及50~组,其中L1、L4、L5椎体PDFF在50~组增长率最大,L2、L3椎体PDFF在30~岁组增长率最大;女性各椎体PDFF在30~组呈轻微下降趋势,此后各椎体PDFF逐渐升高,增长主要集中在40~、50~、60~三个年龄组,其中50~组增长率最大。结论:成人不同年龄组男女性各椎体脂肪分布存在差异,椎体PDFF增长率也有所不同;腰椎不同节段椎体PDFF均与年龄呈正相关。

磁共振脂肪抑制质子密度加权序列诊断骨关节外伤性骨髓水肿的价值

目的:分析磁共振脂肪抑制质子密度加权(PDWI-FS)序列诊断骨关节外伤性骨髓水肿(BME)的价值。方法:选取150例骨关节外伤患者为研究对象,均行矢状位PDWI-FS序列扫描及MRI常规序列扫描,比较两种方法对BME的检出情况、信号强度、图像质量、病灶信噪比及对比噪声比。结果:两种检查方法均显示150例骨关节外伤患者中134例存在225处BME征象,以膝关节外伤患者中多见。PDWI-FS序列显示病灶信号强度主要为3级,占比97.78%(220/225),MRI常规序列显示主要为2级,占比43.11%(97/225),且两种检查方法显示不同强度存在统计学差异(Z=15.919,P<0.05)。PDWIFS序列显示病灶清晰程度、空间分辨力、图像变形及诊断信心评分[(4.09±0.45)分、(3.65±0.42)分、(3.25±0.37)分、(4.21±0.38)分]均高于常规序列[(3.88±0.39)分、(3.41±0.36)分、(3.14±0.35)分、(3.97±0.34)分],且差异均有统计学意义(t=4.319,t=5.314,t=2.645,t=5.765;P<0.05)。PDWI-FS序列显示病灶信噪比及周围组织对比噪声比[(2.07±0.23)、(5.52±0.64)]均大于常规序列[(2.01±0.22)、(5.17±0.59)],且差异有统计学意义(t=2.309,t=4.925;P<0.05)。结论:较MRI常规序列而言,磁共振PDWI-FS序列能有效提高图像质量和病变显示效果,可为骨关节外伤性BME的诊断提供更准确的诊疗信息。

双能CT虚拟去钙技术在“臀坐式”骶尾椎急性损伤诊断中的价值

目的:使用双能CT虚拟去钙技术评估不同经验医师诊断“臀坐式”骶尾椎急性损伤的诊断效能。方法:前瞻性纳入2021年11月至2024年1月因急性外伤导致骶尾部疼痛的29例患者,共174块椎体(145块骶椎、29块尾椎),获取其MRI及DECT数据;以MRI结果为参考,3名放射科医师(诊断经验分别为1、4和10年)分别使用常规CT和VNCa彩色编码图进行分析。结果:使用VNCa技术后,3名医师诊断一致性Kappa值显著提升,分别从0.452、0.615、0.735提升至0.775、0.825、0.897,诊断正确率显著提高,分别为92.5%、94.3%和96.6%,3名医师差异无统计学意义;定量分析表明,正常骨髓的平均VNCa CT值为(-84.2±20.3) HU,骨髓水肿(BME)为(-37.4±18.8) HU,两者有显著差异;以MRI为标准,VNCa CT值区分正常骨髓和BME的AUC为0.962,最佳截断值为-57.1 HU,对应敏感性和特异性分别为91.9%和90.2%。结论:DECT VNCa技术显著提高了不同经验医师诊断骶尾椎急性损伤的效能,尤其对经验不足的医师,VNCa CT值有助于诊断。

动态增强MRI在股骨近端骨髓病变中的应用进展

股骨近端作为机体骨骼系统中的重要承重部位之一,在运动及支撑方面发挥着至关重要的作用,该部位红骨髓含量较为丰富,易发生多种骨髓病变。动态增强MRI(DCE-MRI)可以精确评估股骨近端的血流灌注情况,从微循环层面上对股骨近端病灶进行诊断、鉴别诊断、预后及疗效评估,有助于更深入地理解相关骨髓病变的发病机制和病理生理学信息。就DCE-MRI在股骨近端及相关骨髓病变中的研究进展予以综述。

幼年特发性关节炎MRI特征与临床指标的相关性分析

目的探讨幼年特发性关节炎(JIA)患儿不同临床亚型MRI影像特征的差异,并分析影像特征与临床指标的相关性。方法回顾性收集55例JIA患儿的MRI影像及临床资料,年龄1~14岁,平均(8.1±4.1)岁。患儿分为4个临床亚型,即全身型(12例)、多关节型(17例)、少关节型(16例)、附着点相关关节炎(ERA)型(10例)。观察4型患儿的大、小关节的滑膜增生及骨髓水肿等MRI特征,并对骨髓水肿和滑膜增生进行评分。采用单因素方差分析、Welch检验或卡方检验比较4组间临床资料和影像特征的差异,采用Pearson检验或Spearman检验评估影像学评分与临床指标的相关性。结果55例患儿中,滑膜增生35例,骨髓水肿33例。4型患儿间的红细胞沉降率(ESR)、人白细胞抗原B27(HLA-B27)和足/踝关节受累的差异均有统计学意义(P<0.05)。其中,少关节型患儿足/踝关节受累比例显著高于全身型和ERA型(均P<0.05),余各临床亚型均无特定关节受累倾向。多关节型与少关节型患儿滑膜增生发生率较高,ERA患儿骨髓水肿发生率较高,全身型患儿关节通常只有关节积液(均P<0.05)。比较4种临床亚型患儿的关节评分,ERA型大关节骨髓水肿评分较高,而多关节型和少关节型的小关节骨髓水肿评分较高(均P<0.05);但滑膜增生评分的差异无统计学意义(均P>0.05)。大关节中,骨髓水肿评分与ESR、C反应蛋白(CRP)、年龄呈正相关,滑膜增生评分与年龄、症状持续时间呈正相关(均P<0.05)。小关节中,骨髓水肿评分与ESR、CRP呈正相关(均P<0.05)。结论JIA患儿的受累关节和MRI影像特征在各临床亚型间存在差异,且关节病变评分与临床指标高度相关。

骨髓脂肪对骨转移的影响及磁共振成像定量评估

背景:早期骨转移的准确诊断对治疗方案和预后有着至关重要的作用。骨活检是骨转移诊断的金标准,但由于有创且标本尺寸小等缺点,在实际临床工作中难以落实。近年来,随着MRI技术的不断发展,磁共振定量成像技术如磁共振波谱成像、基于化学移位编码的水脂肪成像等被广泛应用于骨转移的诊断,衍生的标志物包括表信号脂肪分数和质子密度脂肪分数,均能反映骨髓脂肪含量。目前,对于骨髓脂肪在骨转移瘤发生中的作用已经成为了人们关注的新焦点。目的:现就骨髓脂肪对骨转移的影响及磁共振成像定量评估技术进行综述,归纳比较不同磁共振脂肪定量技术评估骨转移的优劣势以及临床应用情况。方法:应用计算机在PubMed和中国知网数据库检索相关文献,英文检索词为“bone metastases,bone marrow adipocytes,magnetic resonance imaging,quantitative MRI,fat fraction,magnetic resonance spectrum,chemical shift encoding-based water–fat imaging”,中文检索词为“骨转移,骨髓脂肪,磁共振成像,定量磁共振成像,脂肪分数,磁共振波谱成像,基于化学移位编码的水脂肪成像”,根据纳入和排除标准共获得相关文献67篇。结果与结论:(1)骨髓脂肪细胞能通过分泌多种相关激素及细胞因子、为肿瘤细胞提供能量、诱导破骨细胞分化等多种途径协助骨转移的发生;(2)磁共振定量技术能够精确地定量脂肪组织,测量骨髓中脂肪含量的变化有助于骨转移的诊断;(3)磁共振波谱成像能够通过不同质子的进动频率反映不同的代谢产物,因此可用于脂肪定量,是目前用于评估转移性骨折的一种辅助检查手段;(4)基于化学移位编码的水脂肪成像可以使水和脂肪信号得以在正相位和反相位相分离,从而测量脂肪组织的信号,在鉴别椎体良恶性骨折方面具有较高的敏感性、特异性和准确性。

MR集合序列定量诊断股骨头坏死的价值

目的:研究MR集合(magnetic resonance image compilation,MAGiC)序列对股骨头坏死的定量诊断价值。方法:回顾性分析2022年2月至2023年8月在某院通过临床病史、临床症状及常规影像学确诊为股骨头坏死的57例患者的髋关节MAGiC序列图像资料,测量股骨头坏死区及股骨颈骨髓水肿区的T_(1)、T_(2)、质子密度(proton density,PD)值,对比坏死区与正常股骨头、水肿区与正常股骨颈的T_(1)、T_(2)、PD值,并对差异有统计学意义的参数绘制ROC曲线,评价其对股骨头坏死与股骨颈骨髓水肿的诊断效能;对比不同ARCO分期患者T_(1)、T_(2)、PD值的差异。采用SPSS 26.0统计学软件进行数据分析。结果:坏死区的T_(1)值明显高于正常股骨头,T_(2)、PD值明显低于正常股骨头,差异有统计学意义(P<0.001)。水肿区的T_(1)值明显高于正常股骨颈,PD值明显低于正常股骨颈,差异有统计学意义(P<0.001)。坏死区的T_(2)、PD值明显低于水肿区,差异有统计学意义(P<0.001)。坏死区的T_(1)、T_(2)、PD值诊断股骨头坏死的AUC分别为1.000、0.947和0.914,敏感度分别为100.0%、89.2%、92.8%,特异度分别为100.0%、96.7%、76.7%,3种定量值对股骨头坏死的诊断效能均较高。水肿区的T_(1)、PD值诊断骨髓水肿的AUC分别为0.969、0.797,敏感度分别为90.4%、86.5%,特异度分别为100.0%、60.0%,T_(1)值对骨髓水肿的诊断效能较高。随着ARCO分期增加,坏死区T_(1)值逐渐增大,T_(2)、PD值逐渐减小。水肿区Ⅰ期T_(1)、T_(2)、PD值均最低,Ⅱ期T_(1)、T_(2)、PD值均最高。结论:MAGiC序列的T_(1)、T_(2)、PD值是诊断股骨头坏死的有效量化参数,T_(1)、PD值是诊断股骨颈骨髓水肿的有效量化参数,T_(2)、PD值是鉴别股骨头坏死与股骨颈骨髓水肿的有效量化参数。MAGiC序列可为定量诊断股骨头坏死提供客观依据。

CT联合MRI鉴别诊断原发性脊柱骨肿瘤良恶性的价值

目的探讨电子计算机断层扫描(CT)联合磁共振成像(MRI)在原发性脊柱骨肿瘤良恶性鉴别诊断中的应用价值。方法选取67例原发性脊柱骨肿瘤患者,均行CT与MRI检查,以病理学检查为“金标准”,比较CT、MRI及二者联合对原发性脊柱骨肿瘤良恶性的诊断准确性。结果病理学检查显示,恶性骨肿瘤31例(46.27%),良性骨肿瘤36例(53.73%)。CT诊断原发性恶性脊柱骨肿瘤敏感度67.74%,特异度75.00%,准确性71.64%,Kappa值0.43;MRI诊断原发性恶性脊柱骨肿瘤敏感度80.65%,特异度77.78%,准确性79.10%,Kappa值0.58;CT联合MRI诊断原发性恶性脊柱骨肿瘤敏感度93.55%,特异度94.44%,准确性94.03%,Kappa值0.88;CT联合MRI诊断原发性恶性脊柱骨肿瘤敏感度明显高于CT(P<0.05),诊断特异度、准确性明显高于CT、MRI(P<0.05)。结论CT联合MRI能够更准确诊断原发性脊柱骨肿瘤的性质,可为临床诊治提供可靠依据。

Triple-modal imaging of stem-cells labeled with multimodal nanoparticles, applied in a stroke model

BACKGROUND Mesenchymal stem cells(MSCs) have been widely tested for their therapeutic efficacy in the ischemic brain and have been shown to provide several benefits. A major obstacle to the clinical translation of these therapies has been the inability to noninvasively monitor the best route, cell doses, and collateral effects while ensuring the survival and effective biological functioning of the transplanted stem cells. Technological advances in multimodal imaging have allowed in vivo monitoring of the biodistribution and viability of transplanted stem cells due to a combination of imaging technologies associated with multimodal nanoparticles(MNPs) using new labels and covers to achieve low toxicity and longtime residence in cells.AIM To evaluate the sensitivity of triple-modal imaging of stem cells labeled with MNPs and applied in a stroke model.METHODS After the isolation and immunophenotypic characterization of human bonemarrow MSCs(hBM-MSCs), our team carried out lentiviral transduction of these cells for the evaluation of bioluminescent images(BLIs) in vitro and in vivo. In addition, MNPs that were previously characterized(regarding hydrodynamic size, zeta potential, and optical properties), and were used to label these cells,analyze cell viability via the 3-[4,5-dimethylthiazol-2-yl]-2,5 diphenyl tetrazolium bromide assay and BLI analysis, and quantify the internalization process and iron load in different concentrations of MNPs via magnetic resonance imaging(MRI),near-infrared fluorescence(NIRF), and inductively coupled plasma-mass spectrometry(ICP-MS). In in vivo analyses, the same labeled cells were implanted in a sham group and a stroke group at different times and under different MNP concentrations(after 4 h or 6 d of cell implantation) to evaluate the sensitivity of triple-modal images.RESULTS hBM-MSC collection and isolation after immunophenotypic characterization were demonstrated to be adequate in hBM samples. After transduction of these cells with luciferase(hBM-MSCLuc), we detected a maximum BLI intensity of 2.0 x10^8 photons/s in samples of 10~6 hBM-MSCs. Analysis of the physicochemical characteristics of the MNPs showed an average hydrodynamic diameter of 38.2 ±0.5 nm, zeta potential of 29.2 ± 1.9 mV and adequate colloidal stability without agglomeration over 18 h. The signal of iron load internalization in hBM-MSCLuc showed a close relationship with the corresponding MNP-labeling concentrations based on MRI, ICP-MS and NIRF. Under the highest MNP concentration, cellular viability showed a reduction of less than 10% compared to the control.Correlation analysis of the MNP load internalized into hBM-MSCLuc determined via the MRI, ICP-MS and NIRF techniques showed the same correlation coefficient of 0.99. Evaluation of the BLI, NIRF, and MRI signals in vivo and ex vivo after labeled hBM-MSCLuc were implanted into animals showed differences between different MNP concentrations and signals associated with different techniques(MRI and NIRF; 5 and 20 μg Fe/mL; P < 0.05) in the sham groups at 4 h as well as a time effect(4 h and 6 d; P < 0.001) and differences between the sham and stroke groups in all images signals(P < 0.001).CONCLUSION This study highlighted the importance of quantifying MNPs internalized into cells and the efficacy of signal detection under the triple-image modality in a stroke model.

幼年型特发性关节炎儿童膝关节骨髓水肿的磁共振影像分析

目的分析幼年型特发性关节炎儿童膝关节骨髓水肿的磁共振成像(MRI)影像表现。方法采用回顾性分析法,对2020年6月至2022年6月期间河南省儿童医院126例幼年型特发性关节炎儿童膝关节骨髓水肿的MRI影像进行分析,其中男性98例,女性28例,年龄(7.85±2.11)岁,病程(8.65±1.05)个月,均为单侧膝关节病变。分析滑膜增厚和血管翳情况、关节囊渗出积液情况、骨质异常情况、关节软骨病变情况、腘窝淋巴结肿大情况、半月板及韧带异常情况、关节软骨内血管影情况。结果幼年型特发性关节炎儿童多发血管翳覆盖关节股骨表面[66例(52.38%)],T1W以低信号为主[96例(76.19%)],T2W以均匀等信号为主[66例(52.38%)]。126例幼年型特发性关节炎儿童均存在少量滑液,其中102例(80.95%)存在髌上囊积液;骨髓水肿以T1W低信号[48例(38.10%)]、T2W片状模糊信号[41例(32.54%)]为主要类型,多发干骺端以骺软骨为基底部的背向关节腔的“火焰”样的骨髓水肿[81例(64.29%)];关节软骨病变以表面毛糙[60例(47.62%)]、局部变薄[36例(28.57%)]为主其中42例患儿存在膝关节腘窝肿大淋巴结影,T1W呈低信号,T2W呈低信号/略低信号,SPIR/3D/FFE呈高信号;患儿半月板以前角/后角变形[45例(35.71%)]、塌陷碎裂[15例(11.90%)]为主,且多发膝关节前后交叉韧带肿胀/局部波浪状改变[21例(16.67%)];72例患儿膝关节软骨内可见与股骨髁关节软骨面垂直排列的辐射状强化的血管影。结论幼年型特发性关节炎儿童的膝关节MRI表现中,多发滑膜增厚、关节腔积液、骨髓水肿,部分患儿伴随软骨破坏和软骨下骨质侵袭。

MRI脂肪抑制技术STIR序列应用于强直性脊柱炎骶髂关节检测的价值

目的:探讨磁共振成像(MRI)脂肪抑制技术短时间反转恢复(STIR)序列应用于强直性脊柱炎(AS)骶髂关节检测的价值。方法:选取2022年1月—2023年7月郑州市中医院收治的60例AS患者作为研究对象。所有患者均进行磁共振成像扫描,扫描序列包括T1加权像(T1WI)、T2加权像(T2WI)、T2加权脂肪抑制(FS-T2WI)及短时间反转恢复序列(STIR)。记录各序列扫描的异常信号,并对比两种脂肪抑制序列骶髂关节左右两侧影像均匀性、两侧臀部肌肉的SNR及CNR、骨髓水肿患者的SNR与CNR、两种脂肪抑制序列图像质量相关评分。结果:经MRI检测,60例AS患者中发现信号异常患者:T1WI 51例(85.00%),T2WI 48例(80.00%),脂肪抑制(FS-T2WI及STIR)59例(98.33%);60例患者中,FS序列右侧图像均匀性较左侧高,FS序列右侧SNR较左侧高,CNR较左侧低,差异有统计学意义(t=1359.047、19.022、21.410,P<0.05);32例骨髓水肿患者STIR序列SNR及CNR均较FS序列高,差异有统计学意义(t=6.457、6.330,P<0.05);STIR序列脂肪抑制均匀性、病变明显性、伪影、整体质量较FS序列高,解剖结构评分较FS序列低,差异有统计学意义(t=44.274、73.891、34.326、25.544、20.440,P<0.05)。结论:采用MRI脂肪抑制技术能够早发现强直性脊柱炎骶髂关节骨髓水肿,且脂肪抑制序列中的STIR序列图像质量更好,尤其对于骨髓水肿患者显示效果更好。