Ankle MR arthrography: how, why, when

MR arthrography has become an important tool for the assessment of a variety of ankle disorders. MR arthrography may facilitate the evaluation of patients with suspected intra-articular pathology in whom conventional MR imaging is not sufficient for an adequate diagnosis and be useful for therapy planning. MR arthrography is valuable in the evaluation of ligamentous injuries, impingement syndromes, cartilage lesions, osteochondral lesions of the talus, loose bodies, and several synovial joint disorders. Indirect MR arthrography is a useful adjunct to conventional MR imaging and may be preferable to direct MR arthrography in cases in which an invasive procedure is contraindicated or when fluoroscopy is not available.     

MR Arthrography of the Hip

Magnetic resonance imaging (MRI) of the hip has been valuable in the diagnosis of occult osseous abnormalities and of periarticular soft tissue disorders. MRI has been less useful in the evaluation of acetabular labral tears and other intra-articular abnormalities. Image optimization is more technically challenging in the hip than in smaller joints because the overlying soft tissues are thicker, resulting in decreased spatial and contrast resolutions that may not be adequate to distinguish the acetabular labrum from subchondral bone, articular cartilage, and joint capsule. MR arthrography (MRA) extends the capabilities of conventional MRI because contrast solution separates intra-articular structures and outlines abnormalities. In hips with suspected acetabular labral injury, arthrographic MR images demonstrate the location and length of tears and the presence of associated capsular defects. Arthrographic MR images may also enable the accurate diagnosis of cartilage lesions and intra-articular loose bodies. This article illustrates normal arthrographic MR features of the hip as well as pathologic disorders of the acetabular labrum, capsule, and articular cartilage     

MR and CT arthrography of the knee

MR and CT arthrography are important imaging modalities for the assessment of the knee in certain situations. Indications for MR arthrography of the knee include assessment of the postoperative meniscus, the presence of chondral and osteochondral lesions, and the presence of intra-articular bodies. The major indication for CT arthrography is evaluating suspected internal derangement in patients who are unable to undergo MRI. In addition to reviewing the established clinical indications for MR and CT arthrography of the knee, the commonly used techniques, normal variants that can simulate disease, and the most commonly found pathologies that can be diagnosed with these modalities are discussed. Potential indications that are not currently well established in the literature including the evaluation of anterior cruciate ligament injury and autologous chondrocyte implants are examined. Where appropriate, the literature on controversial topics or diagnoses is reviewed. The use of conventional imaging versus CT and MR arthrography is also compared.     

Capsulo-labro-ligamentous lesions of the shoulder: evaluation with MR arthrography

PURPOSE: The aim of the study was to analyse the accuracy of MR arthrography in the evaluation of capsulo-labro-ligamentous lesions of the shoulder in patients with glenohumeral joint instability. MATERIALS AND METHODS: From 1999 to 2001 fifty-eight patients with glenohumeral joint instability were studied by MR arthrography. Twenty-seven patients underwent surgical repair: 11 by arthroscopic and 16 by arthrotomic approach. All shoulder evaluations were performed with T1 and T2 weighted axial, coronal and sagittal oblique images, before and after intra-articular injection of gadolinium contrast. RESULTS: Forty capsulo-ligamentous lesions (including 14 capsular ruptures with extravasation of the contrast medium) were detected by MR arthrography. Fifty-two labral tears (36 of the anterior, 13 of the superior and 3 of the posterior glenoid labrum) were identified: 11 out of 52 were not recognized before gadolinium contrast injection. Five rotator cuff tears were identified, one of which was not shown in the pre-injection examination. Surgical results confirmed the MR arthrographic findings in 25/27 patients. In one case MR arthrography did not recognize a SLAP lesion; in another case it identified a tear of the capsule but not of the glenoid labrum. CONCLUSIONS: In many cases of subacute glenohumeral joint lesions with intracapsular fluid, MR may accurately evaluate capsulo-labral-ligamentous lesions. Indeed, the examination of lesions is limited by the absence of the natural contrast determined by fluid; in such cases, intra-articular injection of gadolinium contrast is necessary. MR arthrography evaluates the degree of capsulo-labro-ligamentous tears and may guide the surgical approach.     

Diagnostic value of MR arthrography in detection of intrinsic carpal ligament lesions: use of cine-MR arthrography as a new approach

Twenty-five patients with chronic wrist pain and a preliminary diagnosis of carpal instability were examined with conventional MR imaging and MR arthrography with single compartment intra-articular injection. A new cine-MR arthrography technique, with image acquisition at every 5 s during intra-articular injection, was performed in 17 subjects. The purpose of this study was to determine the diagnostic value of MR arthrography in ligamentous lesions of the wrist and to assess the value of cine-MR arthrography in comparison with arthroscopy and/or surgery. Magnetic resonance arthrography, a semi-invasive technique, increased the diagnostic accuracy of intrinsic carpal ligament injuries. Cine-MR arthrography can be considered as a promising technique especially for the evaluation of lunatotriquetral and scapholunate ligament injuries of the wrist. Received 6 December 1995; Revision received 29 November 1996; Accepted 24 February 1997     

Shoulder magnetic resonance imaging

MRI provides excellent soft tissue contrast and allows for multiplanar imaging in anatomic planes. Because of these advantages MRI has become the study of choice for imaging of shoulder pathology. Some structures, such as the rotator cuff, humeral head contour, and glenoid shape, are evaluated well with conventional MRI. When more sensitive evaluation of the labrum, capsule, articular cartilage, and glenohumeral ligaments is required or when a partial-thickness rotator cuff tear is suspected,magnetic resonance arthrography with intra-articular contrast can be performed. For MR arthrography contrast is injected directly into the glenohumeral joint. This article reviews the appearances of normal anatomic structures in MRI of the shoulder and disorders involving the rotator cuff and glenoid labrum.     

MR arthrography

Review article on MR arthrography: technique and main indications. Intra-articular injection of diluted Gadolinium provides good distension and better appreciation of intra-articular structures than standard MRI. It is useful for partial tears of the rotator cuff, in cases of gleno-humeral instability, lesions of the acetabular labrum and hyaline articular cartilage and also for elbow, wrist and ankle ligamentous ruptures.     

Indirect MR arthrography of anterior shoulder instability in the ABER and the apprehension test positions: a prospective comparative study of two different shoulder positions during MRI using intravenous gadodiamide contrast for enhancement of the joint fluid

Objective. The value of MRI for the evaluation of anterior shoulder instability can be enhanced by shoulder positions that stress the stabilising structures. The ABER position is one that has been described in combination with intra-articular gadopentetate dimeglumine arthrography. We believe that MRI in the Apprehension test position with 90° abduction and maximal tolerable external rotation provides maximum tension on the anterior stabilising structures and with this technique it is sufficient to use indirect gadodiamide arthrography following intravenous injection of the contrast medium. The purpose of this study was to make a prospective comparative evaluation of the ABER and Apprehension test positions when using indirect arthrography with intravenous gadodiamide administration in shoulders with anterior instability. Design and patients. Sixteen patients with persistent anterior instability after recurrent shoulder dislocations were examined in an open MRI unit (0.2 T) following 0.1 mmol/kg of intravenous gadodiamide. Oblique axial T1-weighted imaging was used for analysis. Operative findings were used for correlation. Results. Both the ABER and the Apprehension test position were useful techniques in detecting capsulolabral pathology and Hill-Sachs lesions. The Apprehension test position produced significantly better gadodiamide-enhanced joint fluid in the region of pathology in both the capsulolabral lesion and the Hill-Sachs lesion. It also visualised the size of the Hill-Sachs lesion significantly better than did the ABER position. Conclusion. MRI examination of anterior shoulder instability in the Apprehension test position was more beneficial than examination in the ABER position in visualising capsulolabral and Hill-Sachs lesions when using indirect arthrography.     

MR imaging of rotator cuff tears]

A total of 115 patients with clinical symptoms and signs suggesting rotator cuff tears underwent MR imaging with a 1.5-Tesla system. The body coil was used as the receiver coil in 24 patients and a single 10 cm surface coil in 91. Arthrography or MR imaging with intra-articular Gd-DTPA (MR arthrography) was performed in 95 of the 115. T2-weighted images with the body coil showed high signal intensity lesions in rotator cuffs in only seven of the 10 patients who had tears demonstrated by arthrography or MR arthrography. On the other hand, T2-weighted images with the surface coil demonstrated high signal intensity lesions in cuffs in all 27 patients who were diagnosed to have tears by arthrography or MR arthrography. In 12 patients, T2-weighted images with the surface coil showed high signal intensity lesions in cuffs, while arthrography and MR arthrography did not show tears. Surgery was performed in four of the 12 patients and partial tears were confirmed. A single 10 cm surface coil, 3 mm slice thickness and 2.5 second repetition time seem to account for the fine visualization of cuff tears by the T2-weighted images. These results suggest that T2-weighted images obtained with the surface coil are superior to arthrography and MR arthrography.     

MR-Arthrographie des Sprunggelenkes

Due to its superior soft tissue contrast conventional MRI is the imaging method of choice in the evaluation of ankle joint disorders. Conventional MR imaging can accurately demonstrate normal or acutely injured ligaments; however, in subacute and chronic injury joint fluid necessary for delineation of injured ligaments is absent and MR arthrography should be performed. MR arthrography uses the intraarticular injection of contrast material to distend the joint, yielding improved discrimination of intraarticular structures. This joint distension with MR arthrography is also helpful in the staging of osteochondritis dissecans, since in cases of unstable lesions tracking of contrast material into the interface can be more easily demonstrated. Finally, high contrast and joint distension by MR arthrography improves the detection of intraarticular loose bodies, which often require surgery. MR arthrography, although invasive, may provide additional information in various ankle joint disorders.     

Hip MR arthrography and femoroacetabular impingement

Hip pain is a common complaint among athletes of all ages. Advances in imaging and treatment are changing the paradigm of evaluation and management of hip pain. The role of abnormal femoral and acetabular morphology and lesions of the acetabular labrum and cartilage is increasingly recognized as being crucial in the development of degenerative change. In addition, femoroacetabular impingement is increasingly recognized as an etiologic factor in hip pain. This article discusses techniques of hip magnetic resonance (MR) arthrography, normal anatomy seen at hip MR arthrography, common intra-articular pathologies in patients with hip pain, and imaging findings of femoroacetabular impingement.     

Comparison of MR arthrography with arthroscopy of the hip for the assessment of intra-articular loose bodies

Objective To assess the specificity and sensitivity of MR arthrography of the hip in comparison with arthroscopy for the evaluation of intra-articular loose bodies. Design Over a 3-year period, 81 consecutive patients underwent a total of 82 hip arthroscopies by a single orthopedic surgeon for intractable hip pain. Of the 82 arthroscopies, 70 had pre-operative MR arthrograms. Of these, 57 were available for retrospective review, after which they were compared with the operative notes of the subsequent arthroscopies. Results Of 82 arthroscopies 16 (20%) demonstrated intra-articular loose bodies, while, in the study group, nine of 57 had loose bodies (16%). There was a total of seven discordant cases (five false negatives and two false positives). The sensitivity of MR arthrography for detection of intra-articular loose bodies was 44%, while the specificity was 96%. Conclusion While the specificity of MR arthrography for the detection of intra-articular loose bodies was high (96%), the sensitivity was not nearly as good (44%). Presented at the Special Scientific Section of the ISS in Vancouver, Canada, September 2006.     

Shoulder MR arthrography: which patient group benefits most?

OBJECTIVE: We sought to compare the diagnostic accuracy of conventional MRI versus MR arthrography of the shoulder in the assessment of high-performance athletes (professional baseball players) and to compare our findings in these patients with the conventional MRI and MR arthrographic findings in an age-matched control group of nonprofessional athletes. MATERIALS AND METHODS: Conventional MRI and MR arthrographic examinations of the shoulder in 20 consecutive professional baseball players with shoulder pain were reviewed retrospectively by two musculoskeletal radiologists in consensus. These interpretations were compared with retrospective consensus interpretations of conventional MRI and MR arthrographic examinations of the shoulder obtained in a control group of 50 consecutive nonprofessional athletes with shoulder pain. MR images were assessed for full- or partial-thickness supraspinatus tendon tears, superior labral anteroposterior (SLAP) tears, and anterior or posterior labral tears. RESULTS: In the 20 consecutive professional athlete patients, two full-thickness and six partial-thickness undersurface supraspinatus tendon tears were seen on MR arthrography but not seen on conventional MRI as well as six SLAP tears, two anterior labral tears, and one posterior labral tear. Three patients had both SLAP tears and full- or partial-thickness supraspinatus tendon tears. Of 14 patients with findings on MR arthrography that were not seen on MRI, 11 had arthroscopic correlation. In all 11, arthroscopic findings confirmed findings on MR arthrography. In the group of 50 nonprofessional athlete patients, five had additional findings on MR arthrography not seen on conventional MRI: two anterior labral tears, two partial-thickness supraspinatus tendon tears, and two SLAP tears. One patient had both a partial-thickness supraspinatus tendon tear and a SLAP tear seen on MR arthrography. The five patients with additional findings on MR arthrography had arthroscopy. In all five, arthroscopic findings confirmed the findings on MR arthrography. CONCLUSION: MR arthrography is considerably more sensitive for detection of partial-thickness supraspinatus tears and labral tears than conventional MRI. MR arthrography showed injuries in addition to those seen on conventional MRI in 14 of 20 patients in the high-performance athlete group. These results suggest high-performance athletes may be a subgroup of patients for whom MR arthrography yields considerably more diagnostic information than conventional MRI.     

MR and CT arthrography of the elbow

Magnetic resonance (MR) arthrography has, to a great extent, replaced conventional and CT arthrography as the standard of care imaging tool for indications including medial elbow pain in the throwing athlete, chondral and osteochondral lesions in the elbow, and intra-articular bodies. There are still rare specific incidences where CT arthrography is indicated. This article reviews elbow arthrography, with a greater emphasis placed on MR arthrography, including indications, technique, potential complications, contraindications, equipment, and MR arthrographic pathologies.     

肩关节造影和MRI诊断肩袖损伤

目的评定肩关节造影、MRI诊断肩袖损伤的价值.材料和方法将33例临床诊断肩袖损伤患者的术前关节造影和MRI检查结果与术中观察结果的比较.另有13例复发性肩关节不稳、无肩袖损伤症状和体征的年轻患者术前的关节造影和MRI结果以及术中观察结果作为正常肩袖对照.结果在诊断肩袖完全断裂中,肩关节造影的敏感性为91%,特异性为100%;MRI的敏感性为95%,特异性为88%.结论关节造影诊断肩袖完全撕裂方法简单、迅速且费用低,易于广泛开展.但不能直接显示病变部位.MRI不但能够准确显示断裂的部位,反映肩袖病变的病理过程,而且能同时显示相邻组织的病理改变,更利于诊断和鉴别诊断.     

The carpal ligaments in MR arthrography of the wrist: correlation with standard MRI and wrist arthroscopy

We assessed the value of three-compartment magnetic resonance (MR) wrist arthrography in comparison with non-enhanced magnetic resonance imaging (MRI) for the evaluation of 13 individual wrist ligaments in 35 patients with refractory wrist pain. In 20 of these patients MR findings were correlated with the findings from multiportal wrist arthroscopy. For MR imaging (1.5-T magnet) a three-dimensional volume acquisition with a gradient-recalled echo sequence and 0.6-1.0 mm effective slice thickness was used. The delineation of individual wrist ligaments was rated as "good" in 10% of non-enhanced MR and 90% of MR arthrography images. Ligament evaluation was possible with high diagnostic confidence in 11% by non-enhanced MR imaging and 90% by MR arthrography. With wrist arthroscopy as the standard of reference, average sensitivities/specificities/accuracies for the diagnosis of full-thickness ligamentous defects were 0.81/0.75/0.77 for non-enhanced MR imaging and 0.97/0.96/0.96 for MR arthrography. Our findings suggest that MR arthrography is more accurate than standard MRI in delineating and evaluating the ligaments of the wrist.     

Efficacy of ultrasonography-guided shoulder MR arthrography using a posterior approach

Aim  

Shoulder MR arthrography has an important role in the assessment of rotator cuff lesions, labral tears, glenohumeral ligaments, rotator interval lesions, and postoperative shoulder status. Injection in direct MR arthrography can be performed with palpation, fluoroscopy, ultrasonography (US), or MRI. Recently, the posterior approach is the preferred method due to the presence of fewer stabilizers, absence of important articular structures and less extravasation, has been advocated. Our aim was to assess the efficacy of US-guided MR arthrography via a posterior approach on the glenohumeral joint.     

Evaluation of the acetabular labrum at 3.0-T MR imaging compared with 1.5-T MR arthrography: preliminary experience

Institutional review board approval and informed consent were obtained for this HIPAA-compliant study. The purpose of this study was to prospectively compare imaging of the acetabular labrum with 3.0-T magnetic resonance (MR) imaging and 1.5-T MR arthrography. Eight patients (four male, four female; mean age, 38 years) with hip pain suspicious for labral disease were examined at both MR arthrography and MR imaging. Presence of labral lesions, paralabral cysts, articular cartilage lesions, subchondral cysts, osteophytes, and synovial herniation pits was recorded. There was arthroscopic correlation of findings in five patients. MR imaging depicted four surgically confirmed labral tears that were identified at MR arthrography, as well as one that was not visualized at MR arthrography. MR imaging helped identify all other pathologic conditions that were diagnosed at MR arthrography and helped identify one additional surgically confirmed focal articular cartilage lesion. These results provide encouraging support for evaluation with 3.0-T MR imaging over 1.5-T MR arthrography.     

Direct MR arthrography of plica synovialis mediopatellaris

Objective: To evaluate the efficacy of direct MR arthrography for diagnosing plica synovialis mediopatellaris (PSM).Material and Methods: Twenty-two knees of 19 patients were examined by direct MR arthrography. In 19 of those knees, field-echo T2*-weighted transaxial images were obtained with intra-articular administration of 40 ml of saline ("direct MR arthrography"). In the other 3 knees, T1-weighted transaxial images were obtained with intra-articular administration of 40 ml of gadopentetate dimeglumine. Conventional MR images were evaluated prior to direct MR arthrography in 12 of the 22 knees. The results of direct MR arthrography and conventional MR imaging were compared with the arthroscopic findings.Results: Direct MR arthrography demonstrated 17 of 19 PSMs proved on arthroscopy. The features of 16 PSMs on direct MR arthrography corresponded accurately with the arthroscopic classification. Conventional MR demonstrated only 3 plicae.Conclusion: Direct MR arthrography enabled accurate diagnosis of PSMs and could replace diagnostic arthroscopy.     

MR直接关节造影在腕三角纤维软骨复合体损伤中的应用

目的 通过与腕关节镜结果对照,探讨MR直接关节造影在腕三角纤维软骨复合体(TFCC)损伤中的作用.方法 14例临床怀疑腕TFCC损伤的患者接受了常规MRI和MR直接关节造影,其中10例行腕关节镜检查.MR直接关节造影在腕拇长伸肌腱与伸指总肌腱间隙(相当于桡舟关节间隙)处进针,注入5～7 ml的钆喷替酸葡甲胺(0.1 mmol/L)混合液(0.3 ml钆喷替酸葡甲胺+100 ml生理盐水),与腕关节镜结果相对照,分析常规MRI和MR直接关节造影表现.结果 (1)14例中TFCC尺侧撕裂5例,桡侧撕裂4例,整体损伤5例(包括2例长期类风湿关节炎).(2)在脂肪抑制序列(STIR)及T2和T1WI序列上,损伤的TFCC表现为高信号或等信号,正常的低信号部分或完全消失,MR直接关节造影显示4例桡侧撕裂在腕TFCC的下尺桡关节和5例尺侧撕裂在尺骨茎突附着处可见不同程度的高信号对比剂聚集,5例整体损伤在下尺桡关节和尺骨茎突附着处均可见对比剂.MR直接关节造影表现与腕关节镜结果在损伤部位相符合,包括4例桡侧撕裂,3例尺侧撕裂和3例整体损伤.(3)14例腕TFCC损伤患者,8例伴有下尺桡关节半脱位,6例伴有尺桡骨骨挫伤,常规MRI和MR直接关节造影均可清晰地显示其滑膜反应和骨髓水肿等表现.结论 MR直接关节造影可以清晰地显示腕TFCC损伤,同时与常规MRI相结合能显示伴随的滑膜反应和骨髓水肿.