首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 15 毫秒
1.
Purpose:
To make a comparative analysis of transversal tomograms obtained by high-resolution MR imaging with frozen cross-sections of an anatomical forearm specimen. Twenty-two healthy volunteers were also examined using the same coil system to test for a range of possible clinical applications and for the depiction of morphological and morphometrical values of normal anatomy in vivo.
Material and Methods:
MR images of the carpal tunnel of 22 healthy volunteers were obtained with a 1.5-T whole-body system with a 5-cm surface coil. Measurements were recorded with a field-of-view between 50×50 mm2 and 60×60 mm2 in a 256×256 pixel matrix for the T1 sequence. A slice thickness of 2 mm was used. The images were acquired using a T1-weighted SE sequence (TR/TE 500/38 ms) and a T2-weighted SE sequence (TR/TE 2000/70 ms). Additionally, a formalin-fixed anatomical forearm specimen was imaged for anatomic correlation. The imaged transversal cross-section levels in the specimen were subsequently freeze-sectioned. The anatomical structures of the MR findings were identified and compared with the macroscopical sections of the specimen.
Results:
Based on the good depiction of details at this coil system with a pixel size in T1 of 0.195×0.195 mm, high-resolution MR imaging enabled identification of the interior structures of the carpal tunnel, as well as delineation of connective tissue. The clinical value of high-resolution MR includes the diagnosis of carpal tunnel syndrome and inflammatory disorders of the wrist.
Conclusion:
Our results support the feasibility of high-resolution MR imaging of the carpal tunnel and the wrist using small surface coils.  相似文献   

2.
Objective The arcuate sign is considered a pathognomonic sign for injuries of the posterolateral (PL) corner of the knee. The purpose of our study was to identify different patterns of injury to the fibular head that may associate with injuries to specific ligaments and tendons of the PL corner of the knee. The anatomic relations between the insertions of fibular collateral ligament (FCL), biceps femoris tendon (BFT), popliteofibular ligament (PFL), and arcuate ligament in normal cadaveric knees were also investigated.Design and patients Magnetic resonance imaging was performed in two cadaveric knees which subsequently were dissected. Radiopaque markers were placed upon the fibular insertions of the FCL, BFT, PFL, and arcuate ligament in the dissected knees, and knee radiographs were then obtained. Twelve patients with radiographic or MR imaging evidence of isolated injury to the PL corner of the knee were retrospectively reviewed, with regard to avulsion fractures and marrow edema in the fibular head and the integrity of the ligaments of the PL corner of the knee.Results and conclusions The PFL and arcuate ligament were seen to attach directly to the posterior and medial aspect of the styloid process of the fibular head. The FCL and BFT attached as a conjoined structure on the lateral aspect of the fibular head lateral, anterior and inferior to the attachment site of the PFL and arcuate ligament. Injury to the arcuate ligament or PFL was diagnosed in 8 patients who presented with a small avulsion fracture of the styloid process of the fibula (n=2), bone marrow edema in the medial aspect of the fibular head (n=3), or both (n=3). In 4 patients with injury to the conjoined tendon or FCL, a larger avulsion fragment and more diffuse proximal fibular edema were seen. Radiographic and MR imaging findings in injuries of the posterolateral corner of the knee may suggest injury to specific structures inserting in the fibular head.Presented at the 87th Annual Meeting of the Radiologic Society of North America, 2001.  相似文献   

3.
Our objective was to study the frequency of anterior intermeniscal ligament on MR imaging and to make a classification according to its insertion sites on MR images. Sagittal T1-weighted and thin-section transverse T2*-weighted MR images of the knee were prospectively evaluated in 229 subjects without significant synovial effusion or total rupture of the anterior cruciate ligament. By using thin-section transverse images, the ligament was classified into three types according to its insertion sites (type A: between anterior horns of medial and lateral menisci; type B: between anterior horn of medial meniscus and anterior margin of lateral meniscus; type C: between anterior margins of medial and lateral menisci). On sagittal images location of the ligament was determined with respect to a line drawn between anterior of the tibial epiphysis and posterior of the intercondylar notch to look for a relation between its type on transverse images and location on sagittal images. Separately, arthroscopy was made in 36 patients to verify the MR assessment of the presence of the ligament. Anterior intermeniscal ligament was found in 53% of the subjects. Type B was the most common group (58%). Magnetic resonance imaging has a sensitivity and a specificity of 67 and 100%, respectively, in the detection of the ligament. Types A and C had a statistically significant location posterior and anterior, respectively, to the master line on sagittal images. In arthroscopy, the ligament was either cord-like (67%) or flat (33%) in appearance. Routine sagittal MR images can help identify anterior intermeniscal ligament.  相似文献   

4.
Arthroscopic reconstruction of the anterior cruciate ligament (ACL) using autografts or allografts is being performed with increasing frequency, particularly in young athletes. Although the procedure is generally well tolerated, with good success rates, early and late complications have been documented. As clinical manifestations of graft complications are often non-specific and plain radiographs cannot directly visualize the graft and the adjacent soft tissues, MR imaging has a definite role in the diagnosis of complications after ACL reconstruction and may direct subsequent therapeutic management. Our purpose is to review the normal MR imaging of the ACL graft and present the MR imaging findings of a wide spectrum of complications after ACL reconstruction, such as graft impingement, graft rupture, cystic degeneration of the graft, postoperative infection of the knee, diffuse and localized (i.e., cyclops lesion) arthrofibrosis, and associated donor site abnormalities. Awareness of the MR imaging findings of complications as well as the normal appearances of the normal ACL graft is essential for correct interpretation. Electronic Publication  相似文献   

5.
Objective The aim of this study is to investigate whether virtual MR arthroscopy could be used to visualize the internal architecture of the radiocarpal compartment of the wrist joint in comparison to surgical arthroscopy.Design Diluted paramagnetic contrast material was injected into the radiocarpal compartment prior to MR examination in all patients. A fat-suppressed T1-weighted three-dimensional fast spoiled gradient echo sequence was acquired in addition to our standard MR imaging protocol in each patient. Three-dimensional data sets were then transferred to an independent workstation and were postprocessed using navigator software to generate surface rendered virtual MR arthroscopic images.Patients Nineteen patients referred for chronic ulnar-sided wrist pain were evaluated with conventional MR arthrography prospectively.Results and Conclusion Virtual MR arthroscopic images demonstrating the triangular fibrocartilage complex (TFCC) in an intraarticular perspective were achieved in 12 out of 19 patients. Our preliminary investigation suggests that although it has several limitations, virtual MR arthroscopy shows promise in visualizing the TFCC from an intraarticular perspective.  相似文献   

6.
Objective The objective of this study was to evaluate ultrasound as a diagnostic tool for investigating scapholunate and lunatotriquetral ligamentous and triangular fibrocartilage (TFC) tears. Ultrasound findings were compared to conventional arthrogram findings, as the reference gold standard.Design and patients In total 26 patients, 17 males and 9 females ranging in age from 17 to 35 (mean age, 34), were evaluated on referral for investigation of wrist pain. All patients were examined by high resolution ultrasound, using a 9–13 MHz transducer. All wrist ultrasound examinations were also compared to conventional tricompartmental arthrography, as the diagnostic gold standard reference.Results All ten scapholunate tears confirmed on arthrography were detected on ultrasound. Two of 8 lunatotriquetral and 7 of 11 TFC tears were correctly diagnosed on ultrasound. Sensitivity of ultrasound diagnosis ranged from 25% for lunatotriquetral tears to 100% for scapholunate tears. No false positive results were recorded for any of the three examined structures.Conclusion The study results suggest that sonography is accurate for scapholunate tears, but is not accurate for evaluation of lunate-triquetral tears. It has intermediate accuracy for triangular fibrocartilage tears.  相似文献   

7.
Objective. To compare three-compartment MR wrist arthrography with non-enhanced MRI in correlation with wrist arthroscopy, and to evaluate the potential of MR arthrography for consistently visualizing all parts of the scapholunate interosseous ligament of the wrist (SLIL) and exactly diagnosing the site and extent of SLIL defects. Design and Patients. In 41 patients with wrist pain (34 patients with wrist pain for more than 6 months) plain radiographs, stress views, non-enhanced MRI and three-compartment MR arthrography were done within 2 h of each other, using three-dimensional volume acquisition (0.6–1.0 mm effective slice thickness) with a gradient-recalled echo sequence and a 1.5-T magnet. The MR arthrography findings were compared with the findings from non-enhanced MRI and correlated with the arthroscopic findings in all patients. Results. The dorsal, central and palmar segments of the SLIL could be delineated exactly by MR arthrography in 95% of the patients; with non-enhanced MRI only 28% of SLIL segments were seen consistently. Demonstration of SLIL defects was possible with high diagnostic confidence in 42% of SLIL segments by non-enhanced MRI and in 94% by MR arthrography. With wrist arthroscopy as the standard of reference, sensitivity and specificity values for SLIL perforations were 52%/34% for non-enhanced MRI and 90%/87% for MR arthrography. Conclusions. MR arthrography, using three-dimensional volume acquisition with thin slices (0.6–1.0 mm), combines the advantages of three-compartment arthrography and non-enhanced MRI. It shows the precise location and magnitude of ligamentous defects of all parts of the SLIL, correlates well with wrist arthroscopy and has potential implications for diagnosis and treatment planning.  相似文献   

8.
We sought to clarify the capability of routine magnetic resonance (MR) imaging of the knee to detect and grade tibial collateral ligament (TCL) injury. We also wanted to define the exact MR findings that were the most important for diagnosis. Sixty-three patients were clinically evaluated for TCL injury prior to MR imaging of the knee on a 1.5-tesla system. MR studies were scored with respect to multiple direct and indirect findings. By discriminant analysis, the overall accuracy of classification (into clinical grades 1, 2, 3 and normal) on the basis of MR was 65%. Accuracy for detection of abnormal TCLs was 87%. The most useful MR findings for detection and grading of TCL injury were direct signs: subcutaneous edema over the TCL, focal disruption of the TCL, increased signal in the TCL on T2-weighted images, and longitudinal striations within the TCL. Indirect signs such as trabecular trauma were less useful for TCL evaluation. The presence of a tear of the anterior cruciate ligament, however, correlated with TCL injury of a higher grade. T2-weighted coronal images, by better depicting intraligamentous edema and fiber disruption, improved the MR assessment of the TCL.  相似文献   

9.
Purpose.In the wrist, to determine whether passive motion or active exercise yields a better indirect MR arthrographic effect following intravenous gadolinium administration. Design and patients. Twenty-six consecutive patients were studied by indirect wrist MR arthrography. In half active exercise and in half passive motion was performed. Four regions of interest were studied including the distal radioulnar joint, the radiocarpal joint, the midcarpal joint, and the triangular fibrocartilage. Ranges and means of signal intensity were calculated. Surgical follow-up was performed in 22 patients. Results. The joint fluid intensity was greatest in the distal radioulnar joint. Fluid signal intensity was greater and more consistent in the passive motion group although the results did not achieve statistical significance. Imaging accuracy appeared similar in the two groups and was excellent for the triangular fibrocartilage (100%) and scapholunate ligaments (96%). Conclusion. Active exercise and passive motion yield similar degrees of wrist arthrographic effect, but the effect of passive motion is somewhat more consistent. Preliminary data show good accuracy for internal derangements. Received: 4 June 1999 Revision requested: 6 August 1999 Revision received: 14 September 1999 Accepted: 20 September 1999  相似文献   

10.
PURPOSE: To investigate the three-dimensional (3D) course of the anterior cruciate ligament (ACL) and determine the optimum planes for oblique full-length MRI of the ligament. MATERIALS AND METHODS: Twenty-five healthy volunteers were examined. Axial proton density-weighted (PDw) images of the knees of 20 volunteers were obtained. 3D paths along the course of the ACL and corresponding tangents were constructed. Angles between these tangents and reference lines RFL-1 (the line connecting the posterior edges of the femoral condyles), RFL-2 (the line through the intercondylar joint space), and RFL-3 (the line connecting the anterior and posterior edge of the medial tibial condyle) were measured. These angles were used for oblique T2-weighted (T2w) MRI of the knees of the remaining five volunteers, and the number of slices that depicted the entire ACL was calculated. RESULTS: The mean angles to the ACL were 74.0 degrees for RFL-1, 79.9 degrees for RFL-2, and 70.4 degrees for RFL-3. Full-length visualization of the ACL was demonstrated by 1.4 slices using the sagittal oblique plane prescribed for RFL-1, 2.4 slices using the sagittal oblique plane prescribed for RFL-2, and 1.4 slices using the coronal oblique plane prescribed for RFL-3. CONCLUSION: The ACL is best depicted using a sagittal oblique imaging plane angled at 80 degrees from a line through the intercondylar joint space.  相似文献   

11.
The objective of this study was to assess the value of adding MR arthrography to standard MRI for patients with chronic wrist disorders. Thirty consecutive patients (age range, 19–73 years; mean, 36.2 years) were included in the investigation. The images were evaluated blindly and separately by two radiologists with regard to lesions of the scapholunate (SL) and lunotriquetral (LT) ligaments and the triangular fibrocartilage (TFC). Conventional two- or three-compartment arthrography was used as the standard of reference. For TFC lesions, standard MR images had a sensitivity of 92.3% (reader 1) and 84.6% (reader 2) and a specificity of 41.2% (reader 1) and 52.9% (reader 2). For MR arthrography, sensitivity was 84.6% (reader 1) and 84.6% (reader 2) and specificity was 88.2% (reader 1) and 100% (reader 2). For SL ligament tears, standard MRI had a sensitivity of 33.3% (reader 1) and 11.1% (reader 2) and a specificity of 47.6% (reader 1) and 57.1% (reader 2). For MR arthrography, sensitivity was 66.7% (reader 1) and 55.6% (reader 2) and specificity was 52.4% (reader 1) and 81.0% (reader 2). For LT ligament tears, standard MRI had a sensitivity of 28.6% (reader 1) and 35.7% (reader 2) and a specificity of 93.8% (reader 1) and 81.3% (reader 2). For MR arthrography, sensitivity was 35.7% (reader 1) and 23.1% (reader 2) and specificity was 93.8% (reader 1) and 94.1% (reader 2). In conclusion, the diagnostic performance of MRI in suspected lesions of the TFC and the SL and LT ligaments is improved by adding MR arthrography to the standard examination.  相似文献   

12.
This work demonstrates the potential of ultrashort TE (UTE) imaging for visualizing graft material and fixation elements after surgical repair of soft tissue trauma such as ligament or meniscal injury. Three asymptomatic patients with anterior cruciate ligament (ACL) reconstruction using different graft fixation methods were imaged at 1.5T using a 3D UTE sequence. Conventional multislice turbo spin‐echo (TSE) measurements were performed for comparison. 3D UTE imaging yields high signal from tendon graft material at isotropic spatial resolution, thus facilitating direct positive contrast graft visualization. Furthermore, metal and biopolymer graft fixation elements are clearly depicted due to the high contrast between the signal‐void implants and the graft material. Thus, the ability of UTE MRI to visualize short‐T2 tissues such as tendons, ligaments, or tendon grafts can provide additional information about the status of the graft and its fixation in the situation after cruciate ligament repair. UTE MRI can therefore potentially support diagnosis when problems occur or persist after surgical procedures involving short‐T2 tissues and implants. J. Magn. Reson. Imaging 2009;29:443–448. © 2009 Wiley‐Liss, Inc.  相似文献   

13.
The modified Brostrom procedure is commonly recommended for reconstruction of the anterior talofibular ligament (ATF) and calcaneofibular ligament (CF) with an advancement of the inferior retinaculum. However, some surgeons perform the modified Bostrom procedure with an semi-single ATF ligament reconstruction and advancement of the inferior retinaculum for simplicity. This study evaluated the initial stability of the modified Brostrom procedure and compared a two ligaments (ATF + CF) reconstruction group with a semi-single ligament (ATF) reconstruction group. Sixteen paired fresh frozen cadaveric ankle joints were used in this study. The ankle joint laxity was measured on the plane radiographs with 150 N anterior drawer force and 150 N varus stress force. The anterior displacement distances and varus tilt angles were measured before and after cutting the ATF and CF ligaments. A two ligaments (ATF + CF) reconstruction with an advancement of the inferior retinaculum was performed on eight left cadaveric ankles, and an semi-single ligament (ATF) reconstruction with an advancement of the inferior retinaculum was performed on eight right cadaveric ankles. The ankle instability was rechecked after surgery. The decreases in instability of the ankle after surgery were measured and the difference in the decrease was compared using a Mann-Whitney U test. The mean decreases in anterior displacement were 3.4 and 4.0 mm in the two ligaments reconstruction and semi-single ligament reconstruction groups, respectively. There was no significant difference between the two groups (P = 0.489). The mean decreases in the varus tilt angle in the two ligaments reconstruction and semi-single ligament reconstruction groups were 12.6 degrees and 12.2 degrees , respectively. There was no significant difference between the two groups (P = 0.399). In this cadaveric study, a substantial level of initial stability can be obtained using an anatomical reconstruction of the anterior talofibular ligament only and reinforcement with the inferior retinaculum. The modified Brostrom procedure with a semi-single ligament (Anterior talofibular ligament) reconstruction with an advancement of the inferior retinaculum can provide as much initial stability as the two ligaments (Anterior talofibular ligament and calcaneofibular ligament) reconstruction procedure.  相似文献   

14.
Objective. To describe the MR imaging features of the posterior intermalleolar ligament (IML) in patients with posterior impingement syndrome (PIS) of the ankle. Design and patients. Three patients (one male and two females, 13–25 years of age) are presented. Each patient presented clinically with symptoms of PIS of the ankle. Plain film examination was negative for a structural cause of the PIS in all patients. MR images were obtained with a 1.5 T scanner using an extremity coil. Clinical data and, in one patient, findings at ankle arthroscopy, were correlated with the results of MR imaging. Results. Ankle MR images from the three patients with a clinical diagnosis of PIS are presented. Findings in all patients included: (1) absence of another structural cause of the PIS (i.e., an os trigonum, trigonal process, fracture, loose bodies, etc.), (2) identification of the IML as a structure discrete from the posterior talofibular and tibiofibular ligaments, and (3) prominence of the IML as indicated by (a) identification of the IML in three different imaging planes, and (b) a caliber of the IML comparable to that of the conventional posterior ankle ligaments visualized in the same imaging plane. Arthroscopic resection of a meniscoid IML resulted in resolution of the PIS in one of the patients presented. Conclusions. MR imaging is an effective means of investigating the IML as a potential cause of PIS. The identification of a prominent IML in the absence of another structural cause of PIS indicates that impingement of the IML is the most likely cause of PIS. Received: 11 March 1999 Revision requested: 5 May 1999 Revision received: 2 June 1999 Accepted: 4 June 1999  相似文献   

15.
To determine the exact origin of hip pain can be challenging. Symptoms apparently originating from the hip may arise from the pelvis, the sacroiliac joint, the lumbar spine, periarticular structures such as muscles and bursae, or from unexpected sites such as the abdominal wall, the genitourinary tract, or the retroperitoneal space. This article reviews the differential diagnosis of hip pain arising from the hip and surrounding structures and the role of different imaging methods with emphasis on magnetic resonance imaging where most recent advances have occurred.  相似文献   

16.
Magnetic resonance imaging (MRI) provided adequate depiction of carpal soft tissue structures in normal volunteers, as well as accurate anatomic correlation with cadaveric specimens. Using a high field strength system and surface coil techniques, the intricate anatomy of the wrist was best defined on long TR short TE images. However, from a practical view, T1 weighted images (TR 600 ms, TE 25 ms) were most useful because of short imaging times, satisfactory image quality, and the absence of motion artifacts. The coronal plane provided the clearest definition of important structures. Potential diagnostic limitations exist due to the inability of MRI ot clearly delineate articular cartilage, joint capsules, and small interosseous ligmaents. The presence of intra-articular fluid in both living subjects and cadaveric specimens, however, allowed for fine depiction of these structures on T2 weighted images.  相似文献   

17.
18.
Objective To demonstrate the anatomy of the radial and ulnar bursae of the wrist using MR and US images.Design Ultrasonographic-guided tenography of the tendon sheath of flexor pollicis longus (FPL) and the common tendon sheath of the flexor digitorum of the fifth digit (FD5) of ten cadaveric hands was performed, followed by magnetic resonance imaging and gross anatomic correlation. Patterns of communication were observed between these tendon sheaths and the radial and ulnar bursae of the wrist.Results The tendon sheath of the FPL communicated with the radial bursa in 100% (10/10) of cases, and the tendon sheath of the FD5 communicated with the ulnar bursa in 80% (8/10). Communication of the radial and ulnar bursae was evident in 100% (10/10), and presented an “hourglass” configuration in the longitudinal plane.Conclusions The ulnar and radial bursae often communicate. The radial bursa communicates with the FPL tendon sheath, and the ulnar bursa may communicate with the FD5 tendon sheath.  相似文献   

19.

Purpose:

To prospectively evaluate the diagnostic accuracy of magnetic resonance (MR) arthrography for the detection of articular cartilage abnormalities at 3.0T and 7.0T in cadaveric wrists.

Materials and Methods:

MR imaging (MRI) was performed in nine cadaveric wrists (four right wrists, five left; mean age, 81.0 ± 9.8 years) after the intraarticular administration of gadoterate‐meglumine. A 3.0T and 7.0T MR system, mechanically identical custom‐built 8‐channel wrist coil arrays and a similar standard MRI protocol, were used. MR images were evaluated for visibility of articular cartilage surfaces, presence of cartilage lesions, and confidence of diagnosis by two independent radiologists. Open pathologic inspection served as reference standard. Sensitivity, specificity, negative predictive values (NPV) and positive predictive values (PPV), and accuracy (ACC) were calculated. Wilcoxon signed rank test was used to assess differences in the diagnostic performance.

Results:

Visibility of articular cartilage surfaces was significantly better at 3.0T than at 7.0T (P < 0.001). Mean sensitivity, specificity, NPV, PPV, ACC for both readers were 63%, 90%, 85%, 76%, 82% at 3.0T, respectively, and 52%, 91%, 82%, 75%, 79% at 7.0T. The difference between 3.0T and 7.0T was not significant for reader 1 (P = 0.51), but was significant for reader 2 (P = 0.01). The level of confidence was significantly higher at 3.0T than at 7.0T for both readers (P = 0.004; P = 0.03).

Conclusion:

MR arthrography of the wrist at 7.0T is still limited by the lack of commercially available radiofrequency coils and limited experience in sequence optimization, resulting in a significantly lower visibility of anatomy, lower diagnostic accuracy, and level of confidence in judging cartilage lesions compared to 3.0T. J. Magn. Reson. Imaging 2011;. © 2011 Wiley Periodicals, Inc.  相似文献   

20.
目的观察基于膝关节MR 2DT2WI+fs图像的重建图像对前交叉韧带显示效果,优化扫描程序。方法分析60例前交叉韧带MR检查图像,按检查方法分A、B、C三组进行观察分析。A组:常规扫描标准矢状位图像;B组:基于A组图像的斜矢状位重建图像;C组:斜矢状位扫描图像。观察三组图像对前交叉韧带的显示情况。将图像分二级进行评价:Ⅰ级为前交叉韧带1幅图像完整、清晰显示;Ⅱ级前交叉韧带1幅图像不能完整显示,需连续两幅或三幅图像才能完整显示;最后统计数据进行分析。结果 A组图像:Ⅰ级36例,占60%;Ⅱ级24例,占40%。B组图像:Ⅰ级56例,占93.3%;Ⅱ级4例,占6.7%。C组图像:Ⅰ级5 4例,占90%;Ⅱ级6例,占10%。经计算显示A、B两组图像具显著差异;A、C两组图像具显著差异;B、C两组图像无显著差异。结论基于前交叉韧带MR2DT2WI+fs图像的重建图像对其显示良好,建议膝关节磁共振检查时以标准矢状位扫描所得二维图像进行MPR重建观察,无须特意行斜矢状位扫描或三维成像扫描后重建,可以优化MR检查流程。  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号