MR增强扫描诊断膝关节前交叉韧带部分撕裂

目的:评价MR增强扫描对膝关节前交叉韧带(ACL)部分撕裂的诊断价值。方法:回顾性分析有手术资料的56例患者的膝关节平扫加增强MR扫描图像,分析计算MRI对ACL部分撕裂的诊断价值。结果:MRI平扫诊断ACL 部分撕裂的诊断符合率、特异度、敏感度分别为73．2％、89．2％、82．1％;MRI平扫加增强扫描诊断ACL部分撕裂的诊断符合率、特异度、敏感度分别为91．1％、100％、82．1％。MR平扫加增强对诊断前交叉韧带部分撕裂的诊断符合率明显高于单纯MR平扫,差异有显著性意义(P<0．05);而两者间诊断特异度及敏感度的差异无显著性意义(P>0．05)。结论: 膝关节MR平扫加增强扫描对诊断ACL部分撕裂优于常规MRI扫描。     

膝关节急性前交叉韧带撕裂的常见MRI征象分析

目的 :分析膝关节急性前交叉韧带(anterior cruciate ligament,ACL)撕裂的MRI征象,提高对ACL撕裂的术前诊断和评估能力。方法:回顾性分析117例经关节镜或手术证实急性ACL撕裂患者的临床及影像学资料,分析其MRI征象。结果:117例MRI直接征象主要为ACL纤维中断或部分不连续、弥漫性增粗并信号增高、走行异常、胫骨附着处撕脱骨折;间接征象主要为胫、股骨外侧髁的"对吻性"骨挫伤或骨折、后交叉韧带曲率增大、胫骨前移位、内侧副韧带损伤、内侧半月板撕裂。评估分析5种MRI直接征象得出,ACL走行异常具有相对高的诊断敏感度和特异度;5种MRI间接征象均诊断特异度高而敏感度低。结论 :MRI直接征象能较准确地诊断急性ACL撕裂,并评估其撕裂程度,可作为主要诊断依据;而MRI间接征象特异度较高、敏感度相对较低,不能作为主要诊断依据,但对明确诊断具有较大帮助,可作为辅助诊断依据。     

前交叉韧带损伤的MRI诊断与关节镜下所见的比较研究

目的：探讨MRI对前交叉韧带(ACL)损伤的诊断准确率极其对临床治疗的指导意义。方法：7l例关节镜手术患者术前行MRI检查，根据MRI诊断分为正常、部分损伤和断裂组，将MRI诊断结果与关节镜下所见进行对比。结果：以关节镜下所见为标准，MRI诊断准确率正常组为87．5％(7／8)，部分损伤组为61．9％(13／21)，断裂组为90．5％(38／42)。本组MRI诊断ACL损伤总诊断准确率为95．8％。ACL与胫骨平台夹角小于450和各序列扫描均未见ACL影像为诊断ACL完全断裂的可靠依据。结论：MRI是诊断ACL损伤的有效无创性检查方法，但部分损伤与完全断裂有时难以鉴别，ACL重建术前应常规行关节镜探查。     

前交叉韧带不全撕裂的MRI诊断

目的：探讨前交叉韧带（ＡＣＬ）不全撕裂ＭＲＩ诊断价值、失误原因和进一步提高诊断准确率的方法。材料和方法：收集关节镜证实的１２例ＡＣＬ不全撕裂和１８例正常ＡＣＬ两组病例,采取相同的矢状面和横断面Ｔ１ＷＩ和 Ｔ２ＷＩ成像。结果：单盲法 ＭＲＩ阅片诊断 ＡＣＬ不全撕裂的准确率、敏感性和特异性分别为５７．１％、 ５０％和 ６２．５％。 ＡＣＬ不全撕裂组和正常组的韧带增粗（ｐ＜０．０５）、信号升高（ｐ＜０．０１）和 ＰＣＬ弯曲指数增大（ｐ＜０．０５）均有差别或显著差别,而韧带周信号改变和胫骨前移则无明显差别（ｐ＞０．０５）。结论;ＡＣＬ不全撕裂的直接征象不典型和间接征象少是假阴性的主要原因,部分容积效应和滑膜增生则是假阳性的主要原因,结合临床和多方位、多序列ＭＲＩ成像以及综合分析可进一步提高诊断准确率。     

MRI对膝关节前交叉韧带损伤的诊断

目的 研究正常和损伤的膝关节前交叉韧带的MRI表现。方法 回顾性分析16例前交叉韧带正常和19例前交叉韧带损伤的MRI表现。结果 正常的前交叉韧带在矢状位上呈一连续笔直的T1WI、T2WI均为低信号的带状影。前交叉韧带损伤的MRI表现为韧带连续性中断4例（韧带内形成假瘤1例）,韧带外形不规则4例、韧带水平走向2例和韧带信号增高9例。结论 MRI是一种首选的诊断前交叉韧带损伤的非创伤性检查方法。     

MRI多征象分析对前交叉韧带损伤的诊断价值

目的：评价MRI对前交叉韧带（anterior cruciate ligament,ACL）损伤多种征象的诊断价值。方法：回顾分析了128个膝关节的MR图像。全部膝关节均行关节镜检查,其中52个膝关节的ACL损伤,另外76个膝关节的ACL显示完整。在不告知关节镜结果的前提条件下,2名影像科医生共同对ACL损伤的5个直接征象和10个间接征象进行评价,意见不一致时协商解决差异。结果：在评价的5个直接征象中,ACL不连续和ACL走行异常具有相对高的诊断敏感性和特异性;在评价的10个间接征象中,大多数具有相对高的特异性和低的敏感性,其中空髁间窝征、Notch征、外侧半月板后角裸露征、PCL指数、冠状面PCL单层显示等征象特异性较高。结论：ACL损伤的直接征象为诊断的主要依据,以ACL不连续和ACL走行异常具有较高的诊断价值;ACL损伤的间接征象具有辅助诊断意义,其中空髁间窝征、Notch征、外侧半月板后角裸露征、PCL指数、冠状面PCL单层显示等征象最具有诊断价值。     

前交叉韧带损伤MRI诊断假阳性和假阴性分析

目的 探讨MRI对前交叉韧带损伤诊断的假阳性及假阴性,提高MRI诊断水平.方法 回顾性分析68例(72膝)膝关节外伤后临床怀疑前交叉韧带损伤患者的MRI检查结果,并与关节镜检查结果 进行对照分析.结果 本组68例(72膝)膝关节外伤患者中,以关节镜结果 为标准,MRI诊断结果:真阳性数52例,真阴性数13例,假阳性数5例,假阴性数2例.灵敏度、特异度、假阳性率及假阴性率分别为96.3%,72.2%,6.9%,2.8%,诊断正确率90.3%.结论 MRI是诊断前交叉韧带损伤极有价值的无创方法,但存在一定的假阳性和假阴性,需要结合患者临床病史和更细致的MRI分析.     

膝关节前交叉韧带损伤的MRI诊断进展

<正> 膝关节的前交叉韧带(anterior cruciate ligament,ACL)对维持膝关节的稳定起着重要作用,可限制股骨在胫骨平台上平移和防止胫骨内旋,因其特殊作用及解剖位置,在膝关节韧带中最易受伤。早期准确诊断和全面评估膝关节ACL损伤对及时正确拟定治疗方案,重塑膝关节的稳定和减少继发损伤有重要意义。因ACL特殊解剖特点,MRI诊断还不甚完善,各种脉冲序列、多种检查方法应用对诊断膝关节的特异性、敏感性、实用性报道不一,今     

前交叉韧带重建后的MRI评价

磁共振成像已被证明是诊断膝关节前交叉韧带撕裂的有效方法 ,随着关节镜下前交叉韧带重建术的广泛开展 ,MRI越来越多地被应用到术后的随访中。探讨了MRI评价重建术后移植物完整性的意义     

前交叉韧带重建后的MRI评价

磁共振成像已被证明是诊断膝关节前交叉韧带撕裂的有效方法,随着关节镜下前交叉韧带重建术的广泛开展,MRI越来越多地被应用到术后的随访中.探讨了MRI评价重建术后移植物完整性的意义.     

膝关节前十字韧带撕裂的MRI诊断价值

目的：评价MRI诊断前十字韧带撕裂的价值。方法：对临床拟诊为膝关节前十字韧带撕裂的12例患者，对照分析其MRI资料及手术结果。结果：MRI矢状面9例，冠状面7例显示前十字韧带撕裂。12例中8例前十字韧带内有不规则高信号，4例前十字韧带前缘呈不规则波浪状，1例前十字韧带不连续。12例中6例伴后外侧胜分平台分析。MRI确诊11例。结论：MRI诊断前十字韧带撕裂是有价值的，膝关节后外侧胜管平台分析高度提示急性前十字韧带撕裂。     

前交叉韧带断裂的MRI征象研究

目的 研究前交叉韧带(ACL)断裂的MRI表现,探讨其直接征象和间接征象的产生机制及诊断价值.方法 本组男37例,女3例;年龄16～49岁,平均33岁.急性期断裂28例,慢性期断裂12例,均经关节镜检查和手术证实.采用1.5 T西门子MRI扫描仪,SE或TSE序列T1、12、质子压脂、medic和横断位、矢状位、冠状位多方位成像.组织3名高年资医师进行回顾分析,对ACL断裂的MRI直接征象和间接征象进行统计分析.结果 ACL断裂4|D例中完全性断裂35例,部分断裂5例.急性期断裂的28例直接征象分别为信号中断或不连续24例(86%),信号不均匀18例(64%),韧带肿胀增厚10例(36%);而慢性期断裂的12例分别韧带增厚11例(92%),信号中断或不连续9例(75%),信号不均匀7例(58%),其中韧带增厚征象主要见于慢性期的ACL断裂(P＜0.01).完全性断裂的35例中,28例(80%)发生在中段,上端、下端发生率低;5例部分断裂均发生在前内侧束.ACL断裂的间接征象中,后交叉韧带(PCL)"7"字变形34例(85%);半月板外露26例,其中外侧半月板外露16例(62%);骨损伤15例,其中胫骨撕裂骨折8例(53%);关节间隙增宽9例,其中78%属于慢性断裂;胫骨前移23例(57%).本组40例中,术前正确诊断37例,正确率为92%;3例部分断裂术前未能诊断,漏诊率为8%.结论 根据ACL断裂的直接征象和间接征象,结合外伤史,术前诊断比较容易.     

前交叉韧带损伤的MRI相关征象分析

目的：分析膝关节多种MRI征象对诊断前交叉韧带（ACL）损伤的价值.方法：经关节镜证实的194例患者（包括前ACL正常膝97例、ACL损伤膝97例）,对ACL损伤的相关MRI直接征象和间接征象进行评价.结果：在评价的4个直接征g（ACI,连续性中断、信号缺失、形态异常及走行异常）中,除ACL信号缺失外,其余直接征象对诊断ACL损伤均具有统计学意义,其中韧带连续性中断具有较高的诊断敏感度（83.5%）、特异度（97.9%）及阳性似然比（39.8）.大多数间接征象具有较高的特异性和相对低的敏感性,其中Notch征、骨挫伤、外侧半月板后角裸露征及胫骨前移等征象具有较高的阳性似然比,分别为：＋∞、9.0、55.70和8.0.结论：前交叉韧带损伤的MRI直接征象是其诊断的主要依据;由于其间接征象具有较高的特异性和＋LR,因此可作为前交叉韧带损伤的辅助诊断依据,尤其是直接征象难以确诊的可疑ACL损伤者.     

Accuracy of MRI patterns in evaluating anterior cruciate ligament tears

 The purpose of this study was to determine the different patterns of anterior cruciate ligament (ACL) tears on MRI and the prevalence and accuracy of these patterns. Images were obtained on high-tesla and low-tesla units and the results compared to determine whether field strength affects the interpretation using the grading system. In 172 patients who underwent knee MRI (109 knees with high-tesla units and 63 knees with low-tesla units) and arthroscopy, there was a total of 91 arthroscopically proven ACL tears. Five patterns of ACL tears were observed and designated as type 1 (diffuse increase in signal on T2-weighted images and enlargement of the ligament, 48%); type 2 (horizontally oriented ACL, 21%); type 3 (nonvisualization of the ACL, 18%); type 4 (discontinuity of the ACL, 11%); and type 5 (vertically oriented ACL, 2%). The positive predictive value (PPV) for type 2, 4, and 5 patterns was 100% for both field strengths; for type 3 PPV was just above 80% for both field strengths. The PPV value for type 1 was 90% for the high-tesla unit and 79% for the low-tesla, unit, which was not statistically significant. Combining the results of both field strengths, the overall sensitivity and specificity were 93% and 89%, respectively. Arthroscopic results were also used to determine the association between meniscal and ACL tears. Only 13% of ACL tears were isolated, the rest being associated with meniscal tears. Forty-five percent of medial meniscal and 50% of lateral meniscal tears were associated with an ACL tear, and 94% of ACLs were torn when both menisci were torn.     

膝关节前交叉韧带前内侧束和后外侧束的MR成像研究

目的 提高对膝关节前交叉韧带前内侧束和后外侧束的影像认识,并探讨其3.0T MR的理想常规成像显示平面.方法 回顾性分析149例正常膝关节的3.0TMR图像,采用x2分割法分析前交叉韧带、前内侧束和后外侧束双束结构及双束上、中、下各段在MR矢状面、冠状面、横断面各成像平面显示率的差异.结果 前交叉韧带前内侧束和后外侧束双束结构显示率,横断面(115/149,77.2％)与冠状面(103/149,69.1％)比较,×2=2.4606,P＞0.0125;横断面、冠状面分别与矢状面(21/149,14.1％)比较,x2值分别为119.5138、92.8695,P值均＜0.0125.前内侧束和后外侧束双束上段显示率,横断面( 104/149,69.8％)与冠状面(7/149,4.7％)、矢状面(0/149,0)及冠状面与矢状面分别比较,x2值分别为135.0813、159.7526、7.1684,P值均＜0.0125.前内侧束和后外侧束双束中段显示率,横断面(108/149,72.5％)与冠状面(94/149,63.1％)比较,x2=3.0120,P＞0.0125;横断面、冠状面分别与矢状面( 10/149,6.7％)比较,x2值分别为134.7454、104.2173,P值均＜0.0125.前内侧束和后外侧束双束下段显示率,横断面(103/149,69.1％)与冠状面(110/149,73.8％)比较,x2=0.8065,P＞0.0125;横断面、冠状面分别与矢状面(18/149,12.1％)比较,x2值分别为100.5300、115.9132,P值均＜0.0125.前交叉韧带双束各段在MRI各序列上均呈低信号,形态、走行正常.结论 3.0TMR常规扫描平面能够在一定程度上显示前交叉韧带的双束结构,横断面和冠状面是较为理想的显像平面.     

Mucoid degeneration of the anterior cruciate ligament mistaken for ligamentous tears

Objective. To describe the MR features of mucoid degeneration of the anterior cruciate ligament (ACL) in a series of patients with MRI findings that were mistaken for tears in the majority of cases but who were found to have an intact ligament at arthroscopy. We will suggest a pathologic entity corresponding to this finding and describe some characteristic features that can be used to identify this entity on MRI. Design. A retrospective analysis of 10 MRI examinations of the knee was performed after arthroscopic evaluation. Prearthroscopic MRI findings had been interpreted as a tear in six patients prospectively and in the remaining four the diagnosis of mucoid degeneration was suggested and ultimately proven. All patients had an intact ACL by preoperative clinical examination, examination under anesthesia, and at arthroscopy. Results. MRI examinations demonstrated an ill-defined ACL, greater in girth than the normal ligament and characterized by increased signal on all sequences. The high-signal ligament was oriented in the normal direction of the ACL. The overall appearance of the ligament was retrospectively described as like a celery stalk. Arthroscopy demonstrated mechanically intact ligaments with a normal to expanded external appearance. Probing of three of the ligaments caused a material to be expressed and pathologic evaluation resulted in the diagnosis of cystic, mucoid degeneration. Conclusion. Mucoid degeneration and an intact ACL can be suspected when an apparently thickened and ill-defined ligament with increased signal intensity on all sequences is identified in a patient with a clinically intact ligament. Received: 10 April 2000 Revision requested: 18 July 2000 Revision received: 13 November 2000 Accepted: 27 November 2000     

前交叉韧带重建术后三维MRI表现

目的 探讨前交叉韧带(ACL)重建术后ACL移植物和骨隧道的3D MRI表现和演变规律.方法 回顾性分析26例双束ACL重建和16例单束ACL重建患者行3D MRI术后随访56例次的资料,用多平面重组法显示和评价移植物、骨隧道、固定器及并发症,计算术后不同时期低信号及高信号移植物的比例和骨隧道周围骨髓水肿的出现率.结果 发现低信号移植物24例次,高信号移植物32例次.移植物固定2例股骨端采用横杆,1例股骨端使用纽扣,其余部位使用可吸收螺钉.术后3个月、6～9个月和12个月及以上低信号移植物比例分别为20/25、0/14和4/10,高信号移植物比例分别为5/25、14/14和6/10,骨隧道周围骨髓水肿出现比例分别为54/54、10/32和4/26.发现1例移植物撕裂,4例胫骨隧道偏前伴ACL移植物髁间窝顶撞击,3例股骨隧道偏前,2例可吸收螺钉与骨隧道不匹配.结论 3D MRI可准确显示ACL重建术后移植物、骨隧道和固定器的状态及并发症信息,移植物信号在术后呈先增高再恢复低信号的过程.     

Association of peripheral vertical meniscal tears with anterior cruciate ligament tears

OBJECTIVE: The purpose of this article is to describe a type of meniscal tear seen on magnetic resonance (MR) imaging, the peripheral vertical tear, and to determine the prevalence of anterior cruciate ligament (ACL) tears in knees with this type of meniscal tear compared to knees with other types of meniscal tears. MATERIALS AND METHODS: Following Institutional Review Board approval, a retrospective review of 200 knee MR examinations with imaging diagnoses of 'meniscal tear' was performed to assess the location and morphology of the meniscal tear, and to assess the status of the ACL. RESULTS: Nineteen peripheral vertical meniscal tears were identified in 17 patients, 14 of whom had acute ACL tears, prior ACL reconstruction, or chronic ACL deficiency. Three peripheral vertical tears were seen in the setting of a normal ACL. Of the 183 examinations with other types of meniscal tears, there were 17 cases with acute ACL tears, prior ACL reconstruction, or chronic ACL deficiency. The difference in the prevalence of ACL tear, reconstruction, or deficiency in knees with meniscal tears of the peripheral vertical type (82.4%) compared with the prevalence of ACL tear, reconstruction, or deficiency in knees with other types of meniscal tears (9.3%) was statistically significant (P < 0.001). The calculated specificity of the presence of peripheral vertical tear morphology in detecting an ACL injury in patients with meniscal tears was 98.2%. CONCLUSIONS: Peripheral vertical meniscal tears, particularly when involving the posterior horn, are highly associated with ACL tear, deficiency, or reconstruction. The finding of this type of tear on knee MR imaging should prompt close inspection of the ACL for evidence of acute or chronic injury, and its presence may help make the diagnosis of ACL tear in equivocal cases.