Gadolinium-enhanced MR Imaging of Epiphyseal and Metaphyseal Marrow in Normal Piglets

Summary： The purpose of this study is to define the appearance of normal epiphyseal and metaphyseal marrow and normal changes of marrow due to fatty conversion on Gadolinium （Gd）-enhanced MR Imaging. Unenhanced and enhanced Tl-weighted MR imaging were performed in proximal and distal femoral ends of 8 healthy piglets at the ages of 2, 4, 6 and 8 weeks, respectively. The changes with age in signal intensity and enhancement ratio of the epiphyseal and metaphyseal marrow with age were examined. The correlation of MRI characteristics with histological findings was stud- ied. Our study showed that marrow of the metaphysis and of periphery of the 2nd ossification center were well vascularized hematopoietic marrow and had great enhancements. The enhancement ratio of metaphysis was greater than that of epiphyseal marrow and both enhancement ratios degraded gradually with age. The central regions of the epiphyseal ossification center and of the diaphysis were of fatty marrow and had little enhancement. It is concluded that on Gd-enhanced MR imaging the hematopoietic marrow of metaphysis and of periphery of the 2nd ossification center had greater enhancement than that of fatty marrow of central region of the 2nd ossification center. All of their enhancements decreased gradually with age.     

Dynamic gadoteridol-enhanced MR imaging in the end of growing long bone of piglets

Background It is of value to identify the non-invasive means that can accurately reflect the blood supply of epiphysis and is more sensitive in detection of early ischemia of epiphysis than the conventional gadoteridol （Gd）-enhanced SE TlWI. The aim of this study was to evaluate the blood supply of various anatomic regions at the end of normal growing long bone using dynamic Gd-enhanced MR imaging and compare the sensitivities between dynamic Gd-enhanced MR imaging and conventional Gd-enhanced SE TlWl in the detection of decreased blood perfusion of early epiphyseal ischemia. Methods Twenty-seven two-week-old piglets were used in this study. For the study of the end of normal growing long bone, unilateral MR imaging of the distal femur and proximal tibia was performed on eleven piglets. The comparison was made among various anatomic regions （physeal and epiphyseal cartilage, metaphyseal spongiosa, the secondary ossification center and metaphysis） using MRI in terms of the enhancement ratio and speed. Their relationships with the histological findings, including RBC/mm^2 and vessel distribution, were evaluated. To examine ischemic femoral head, 16 piglets were divided into two groups, with the control group having 8 piglets （involving 16 normal hips） and an ischemic group having 8 piglets （involving 16 hips with hyperabduction）. In the ischemic group, MR imaging was performed on the hips in the hyperabduction immobilized persistently for 30 minutes. After MRI, the piglets were allowed to ambulate freely for 1 day and the same MR scanning was then repeated in a neutral position. The difference in enhancement ratio and speed of the femoral head between the control and ischemic group were evaluated. Results With regard to the end of normal growing long bone, the enhancement ratio of the metaphyseal spongiosa was greatest among all the anatomic regions （P 〈0.001）. The enhancement ratio of physeal cartilage was greater than that of epiphyseal cartilage （P 〈0. 001）, which was the lowest in al     

异时性多中心骨巨细胞瘤伴腹膜后转移

Giant cell tuenor （GCT）of bone is a benign but locally aggressive tumor that usually involves the epiphysis of long bones.1Rarely,these tumors metastasize to the lung, and these metastases generally have the same benign histological appearance as the primary tumor. Multicentric giant cell tumor （M-GCT） is rarer. We herein report a case of M-GCT involving the left distal radius, with retroperitoneal metastasis, and subsequent lesions in the left proximal and distal femur. The patient and family members were informed that data concerning the case would be submitted for publication, and they consented.     

AN ANATOMICAL STUDY OF CALCAR FEMORALE AND ITS CLINICAL SIGNIFICANCE

Calcar femorale, the integral part of upper femur, is studied with femur bonespecimens from human, monkey and bovine species and in conjunction with roentgenographyand scanning tomography of the human upper femur. The calcar femorale can be classfiedmorphologically into three types. On the average, the calcar femorale extends proximallyfrom 1.46±0.52 cm above the lesser trochanter to distally 0.42±0.60 cm below the distalmargin of the lesser trochanter. In 80% of the femurs, the widest and thickest part ofthe calcar is near the proximal margin of the lesser trochanter. The values of 5parameters of human calcar are provided. The development of calcar femorale amongChinese is fully accomplished at the age of 7-11. Bovine and monkey also has calcar butthe direction of its transverse axis is statistically different from that of the humans.     

<Emphasis Type="Italic">In vitro</Emphasis> 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 (P<0.01). 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.     

Repair effect of articular cartilage defects by nitric oxide synthase inhibitor

Objective To discuss repairing effects of articular cartilage defects by nitric oxide synthase inhibitor (S methylisothiourea, SMT), and explore the role of nitric oxide in cartilage repair. Methods Full-thickness defects of cartilage were created in the intercondylar trochlear groove of femur of thirty-six adult New Zealand white rabbits, and were divided into three gorups. Twenty-four defects were untreated as the control, twenty-four were filled with fibrin glue and impregnated with rhBMP AS rhBMP group, the rest twenty-four were filled with fibrin glue and impregnated with rhBMP, and hypodermic injection with SMT as SMT group. The animals were sacrified at sixteen weeks postoperatively, and the gross appearance of the defect was estimated. The repair tissue was examined histologically and was evaluated according to the grading scale of histology. The amount of released NO and the activities of nitric oxide synthase(NOS) were examined by chemical colorimetry. The distribution of type-Ⅰ , Ⅱ collagen     

REPEATED RECURRENCE OF OSTEOSARCOMA TREATED BY RESECTIONS AND CHEMOTHERAPY

This paper presents 5 patients with repeated recurrence of osteoeareoma (RROS). The primary focus of 3 patients were in the distal portion of femur, and 2 patients were in the proximal portion of tibia. Three patients, whose chest X ray film were negative, were treated by amputation and chemotherapy. Two patients had isolated metastatic focus 1.5cm in diameter in lung, were treated by amputation after 1 week of chemotherapy and then treated by lobectomy after 2 weeks of chemotherapy. After operation, the chemotherapy was carried out for 3 courses of treatment. The roentgenogram of chest and affected limb were taken once every two months. There were metastatic focuses found in the lung of 1 patient and in the distal portion of femur of 2 patients. One patient was operated on for 4 times. Up to now, 3 patients havebeen living for 5 years and 2 patients for 6 years after operation.     

EXPRESSION OF BONE MORPHOGENETIC PROTEIN-1 IN FETAL HUMAN CARTILAGE AND BONE DURING ENDOCHONDRAL OSSIFICATION

The expression ot mRNA for bone morphogenetie protein-l(BMP-1) was investigated in fetal human cartilage and bone during the developing endoehondral ossification by using in situ hybridization. BMP-1 mRNA was localized in the hypertrophic choadrocytes, the cells of perichondrium, osteoblasts and marrow cells. The results suggest that BMP-1 may involve in cartilage and bone formation, and in regulation of calcification of growth plate. As a comparative study, the expression of TGF-β1 protein was investigated in cartilage and bone using immunohistoehemical staining, correlated expression of TGF-β1 and BMP-1 was found. The results suggest that BMP-1 and TGF-β1 act synergistically to influence endochroodral ossification.     

A TETRACYCLINE LABELING STUDY OF SUBCHONDRAL BONE TISSUES IN OSTEOARTHRITIC HIP JOINT

Seven female patients (mean age of 56 years) with advanced hip joint osteoarthritis underwent total hip replacement. Four days before operation they were given oral tetracycline for two days. During operation specimens were taken from the white articular cartilage, the yellowish articular cartilage and the ivory bone together with their subchondral bone tissues. The undecalcified specimens were cut into 10 μm sections and observed under the fluorescence microscope. In all the specimens the following findings could be observed. 1. The osteoarthritic articular cartilage became thinner, with uneven surface and fissures. 2. The superficial and deep surfaces and the central part of the subchondral bone plate showed bright golden yellow fluorescence. It reflected extensive new bone formation. 3. The subchondral bone trabeculae also revealed bright golden yellow fluorescence on their peripheral borders, so trabeculae turned thicker obviously. 4. The marrow tissues between the bone trabeculae exhibited particulate or spherical bright golden yellow fluorescence, reflecting new bone formation in the marrow. The particulate and spherical bright golden yellow fluorescent materials might aggregate, enlarge and merge into large piece of new bone and they also fused with the neighbouring bone trabeculae. The aforementioned changes in the structure of the subchondral bone tissues increased greatly the mass in the osteoarthritic femoral head.     

Early Reversible Ischemia of Femoral Head Epiphysis in Piglets on Gadolinium-enhanced MRI： An experimental study

According to literatures, ischemia of the femoral head epiphysis is one of the most common complications dur- ing closed or open reductions of the hip performed for treating hip joint dysplasia[1]. Once ischemia of the femoral head epiphysis took place, the epiphyseal cartilage, growth plate cartilage and secondary ossification center would be affected, and the cartilage or bone in femoral head epiphysis may suffer from necrosis, which could be followed by growth arrest and deformity of the sec…     

Clinical significance of magnetic resonance imaging of bone marrow in patients with leukemia

Acute leukemia is a clonal malignancy ofhematopoietic tissue characterized by proliferation ofabnormalblastcellsin the bone marrow and impairedproduction of normal blood cells.Magnetic resonanceimaging( MRI) isuseful in characterizing normal andabnormal bone marrow ( BM) because of its ability todistinguish fatfrom denser,more cellulartissuessuchas leukemia.MRIalso presentsa more global view ofthe BM than biopsy materials and,therefore,mayprovide a better understanding of diffuse hematopoi-…     

纤维性骨皮质缺损的MRI诊断与鉴别诊断

目的探讨纤维性骨皮质缺损的MRI表现及其鉴别诊断。方法对32例经随访观察1～4年（26例）、临床病理证实（6例）的纤维性骨皮质缺损患者的临床资料及MRI表现进行分析,并加以鉴别诊断。结果 32例纤维性骨皮质缺损中,位于股骨远侧干骺端16例,股骨骨干下段3例,股骨近侧干骺端3例,胫骨近侧干骺端8例,胫骨骨干上段2例;右侧17例,左侧15例;且病灶大多位于病骨后侧份,内侧份皮质区;病灶大多呈类圆形、椭圆形,边界清楚,周围未见骨膜反应及软组织肿胀,病灶大小约0.5～2.6cm,多呈稍长T1稍长T2、稍短T2信号,并周围见低信号线样改变,11例增强扫描均有不同程度强化,多为轻～中度。14例经随访观察,其中7例病灶无改变,5例病灶稍有缩小,2例发展为非骨化性纤维瘤。结论纤维骨皮质缺损的MRI表现有一定的特征性,有助于该病的诊断,并能进行鉴别诊断。     

儿童髋关节影像解剖学观测及临床意义

目的：：通过尸体解剖及相关 X-ray 扫描研究儿童髋关节的正常解剖,为影像学及临床诊断与治疗提供解剖学基础和参考依据。方法：经福尔马林液固定儿童尸体骨骼标本,进行解剖测量,并记录数据。同时对1例正常儿童髋部的 X-ray 扫描片进行影像学观测。结果：骨折线及骨骺线与股骨头近端 a水平线距离：头下型（20.14±0.5）mm、头颈型（21.42±0.5）mm、经颈（颈中）型（25.50±0.5）mm、基底型（28.82±0.5）mm、骨骺线（19.50±0.5）mm。儿童髋部正常影像学表现：以11岁男性为例,可见股骨头和股骨颈以及大转子、小转子未与股骨融合。结论：根据影像学与解剖测量的结果可为儿童股骨近端骨骺线与骨折线的鉴别与临床诊断治疗提供理论依据。     

MRI在Legg-Calve-Perthes disease中的应用

目的探讨LCP病的MRI表现和诊断价值。方法回顾性分析14例LCP病（15髋）临床和MRI资料,研究LCP病不同分期MRI影像学表现。结景缺血坏死期,2髋;血运重建期,6髋;修复期,7髋。MRI显示髋关节滑膜炎（15髋）,关节积液（15髋）,关节面滑膜侵蚀（5髋）,骨髓水肿（7髋）,髋臼和股骨头软骨增厚（6髋）,扁平髋（2髋）,股骨干骺端和股骨头骨骺间骨桥（3髋）。结论MRI是评价LCP病有效工具,可应用于诊断股骨头坏死,为疾病准确分期、各种并发症的发现及患者预后,提供重要信息;指导制定非手术和手术治疗方案具有重要意义。此外MRI还可以鉴别其它儿童髋关节疾病。     

正常乳猪生长软骨:MR表现特征与组织学发现的相关性对照和横向及纵向弛豫时间测定

目的 :明确正常生长软骨的MR信号特征及与组织学发现的相关性 ,检测乳猪骨骺软骨和生长板软骨T1和T2弛豫时间的不同。方法 :12例出生仅 2周的乳猪 ,用 1.5TeslaGEMR仪对双侧股骨远端和胫骨近端骨骺进行扫描 ,将MR所显示的各层微细解剖结构的信号特征与相应组织学构造进行比较对照。运用多层面多回波自旋回波MR序列进行T2弛豫时间测量 ,运用反转恢复系列进行T1弛豫时间测量。结果 :MRI显示了二次骨化中心骨髓和干骺端之间的 5种不同的微细解剖结构 ,它们分别为 :①二次骨化中心的临时钙化带 ;②二次骨化中心的生长板 ;③骨骺软骨 ;④生长板 ;⑤临时钙化带。股骨生长板软骨的T2 和T1值与骨骺软骨相比有显著延长 ,两者之间的差异有显著性意义 (P <0 .0 5 )。结论 :MRI能够鉴别骨骺软骨和生长板软骨。生长板和骨骺软骨T2 和T1值的不同主要是因为软骨基质内水分子被蛋白粘多糖束缚的状态不同所致     

Epiphyseal and Physeal Cartilage： Normal Gadolinium-enhanced MR Imaging

Jaramilloet al[1] revealed that abnormal perfu sion of the proximal femoral epiphyseal cartilage isdetectable using Gadolinium ( Gd) enhanced MRimaging. His study also indicated that cartilagi nous ischemia may be reversible if detected andcorrected early. We believe that the study of nor mal growth cartilage with Gd enhanced MR ima ging is necessary to further setting up diagnosticstandards for cartilaginous ischemia. In this study,vascular anatomy was d…     

MRI Characteristics and Transverse Relaxation Time Measurements in Normal Growing Cartilage

Itisimportanttobefamiliarwiththehistologicstructuresofgrowingcartilageindetailforclinicaldi agnosis .Histologicalfindingsoftheendsofimmaturebonesdefinethreecartilaginousstructures:(1)thephysealcartilage ,(2 )theepiphysealcartilage ,and(3)thearticularcarti…     

Bax蛋白在骺板软骨细胞中的表达

目的：研究凋亡相关基因Bax在正常骺板软骨细胞中的表达。方法：采用免疫组化ABC法。结果：Bax的免疫反应阳性物在正常骺板软骨的各个区中有不均衡的表达，在骺板软骨膜下的软骨细胞中没有Bax表达；在骺板的静止区Bax的免疫反应阳性物在软骨的细胞质中表达；在骺板的增殖区位于细胞质中的Bax免疫阳性反应增强；在骺板的肥大区Bax的免疫反应强度达到最大值，免疫反应阳性物位于软骨细胞的胞质和胞核中。结论：Bax可能通过数量的积累促使骺板软骨细胞凋亡。