Paroxetine in the treatment of generalized social phobia: open-label treatment and double-blind placebo-controlled discontinuation

Sixty-nine patients with traumatic knee hemarthrosis were evaluated an average of 3 days after trauma by high field (1.5T) magnetic resonance imaging (MRI) using sagittal T1, T2-weighted and coronal 3D-gradient echo images. All knees were arthroscopically examined shortly afterwards. The diagnostic validity of MRI for intraarticular pathology was determined using arthroscopy as golden standard. All patients had pathological findings on arthroscopy. The injuries were sports-related in 77% of the cases. MRI was highly sensitive (86%) and specific (92%) for diagnosis of anterior cruciate ligament tears. Diagnosis of medial meniscal tears showed a 74% sensitivity and 66% specificity. MRI detected lateral meniscal tears in 50% with an 84% specificity. As such, MRI missed 10 significant meniscus ruptures requiring surgical treatment. The sensitivity for partial or total medial collateral ligament tears was 56%, the specificity 93%. Rupture of the medial retinaculum in cases with patellar dislocation or significant damage of articular cartilage were only detected by MRI in a few cases (27% and 20% sensitivity, respectively). MRIs low diagnostic validity for intraarticular pathology with hemarthrosis may be attributed to the shifting paramagnetic properties of the blood remains and catabolic processes in meniscal and chondral tissues during the hemoglobin degradation process. Accordingly, MRI, with the technique used, could neither replace arthroscopy in the diagnosis and screening of acute knee injuries, nor select patients with need for immediate arthroscopic meniscal surgery.     

MRI of meniscal bucket-handle tears

OBJECTIVE: A meniscal bucket-handle tear is a tear with an attached fragment displaced from the meniscus of the knee joint. Low sensitivity of MRI for detection of bucket-handle tears (64% as compared with arthroscopy) has been reported previously. We report increased sensitivity for detecting bucket-handle tears with the use of coronal short tau inversion recovery (STIR) images. DESIGN AND PATIENTS: Three hundred and twenty-seven patients who had MRI of the knee between October 1994 and December 1996 and subsequently underwent arthroscopy were included in the study. We prospectively and retrospectively reviewed the MR examinations of the 30 patients with arthroscopically proven bucket-handle tears. Each of two observers examined each scan for the three traditional findings of bucket-handle tears: a double posterior cruciate ligament sign, a flipped meniscus sign and/or a fragment in the intercondylar notch. We also assessed STIR images in the coronal plane through the menisci looking for an area of increased signal within either meniscus with a displaced meniscal fragment. RESULTS: By using four criteria for diagnosis of meniscal bucket-handle tears, our overall sensitivity compared with arthroscopy was 93% (28 of 30 meniscal bucket-handle tears seen at arthroscopy were detected by MRI). The meniscal fragment was well visualized in all 28 cases on coronal STIR images. The double posterior cruciate ligament sign was seen in 8 of 30 cases, the flipped meniscus was seen in 10 of 30 cases and a fragment in the intercondylar notch was seen in 18 of 30 cases. CONCLUSION: By using four criteria for diagnosis of bucket-handle tears, overall diagnostic sensitivity of MRI compared with arthroscopy increased from the previously reported 64% to 93%. Coronal STIR images are useful for detecting small meniscal bucket-handle tears.     

Office arthroscopy: a diagnostic alternative

Twenty patients with enigmatic knee symptoms were selected for evaluation by both magnetic resonance imaging (MRI) and office arthroscopy. Office arthroscopy was performed in a standard examination room using a miniature (1.7 mm) fiberoptic arthroscope under local anesthesia. All MRI scans were performed on a state-of-the-art 1.5-T magnet unit, and included specialized cartilage sequences in 7 patients. In 14 patients, 26 areas showed articular cartilage changes by arthroscopy (grade 2-3). Only nine of these areas were detected by MRI (sensitivity 34.6%). There were five false-positive and four false-negative readings of meniscal tears by MRI as compared with office arthroscopy. These results improved when postoperative menisci were excluded. Only one of three anterior cruciate ligament (ACL) disruptions identified by MRI could be verified by arthroscopy. The one posterior cruciate ligament (PCL) disruption was confirmed by both techniques. MRI was superior to arthroscopy in identifying bone contusions, subchondral sclerosis, and medial cruciate ligament (MCL) sprains. Office arthroscopy is an accurate and cost-efficient alternative to MRI in diagnostic evaluation of knee pathology in patients with enigmatic symptomatology.     

Correlations between clinical examination/MRI/arthroscopy in the acute traumatic knee

Authors study retrospectively 81 cases of isolated recent (less than three months) knee traumas. These include clinical aspects, NMR, arthroscopy. Clinical examinations have been graded: 1. possible lesion; 2. likely lesions; 3. confirmed lesions. Clinical examinations and NMR results are compared to arthroscopy considered as reference. Clinical examination of acute traumatic knee is essential. Nevertheless, its value for detecting precise lesions is poor, except for knee locking well correlated with meniscal tears. Results show that NMR provide better results than clinical examination. NMR is reliable for detecting tears of posterior cruciate ligament, tears of posterior horn of menisci (sensibility: 93%; specificity: 80%). Its results are less effective for appreciation of lesion of anterior cruciate ligament (sensibility: 88%; specificity: 78%) because of partial tears and functional but not morphologic damage. It is the only method able to evidence osteochondral injuries and soft-tissues associated lesions in traumatic knees. Emergency NMR scans show results no differences in results compared with routine examinations. However, one should keep in mind that negative NMR cannot exclude small cartilaginous lesions and partial tears of anterior cruciate ligament. According to these results and the known qualities of NMR (non invasive), we propose that this type of investigation should be more largely included in diagnostic attitude for acute injured knee. Emergency diagnostic arthroscopy could be efficiently replaced by NMR knee examination.     

MR imaging of tears of discoid lateral menisci

OBJECTIVE: The purpose of this study was to determine the positive predictive value (PPV) for diagnosis of discoid lateral meniscal tear using MR imaging and to describe various patterns of such tears in the knee. SUBJECTS AND METHODS: MR reports of 77 patients (10-67 years old) who underwent prospective MR imaging that led to a diagnosis of discoid lateral meniscal tear were correlated with arthroscopic results. MR images obtained in 71 patients confirmed to have discoid lateral meniscial tear were retrospectively reviewed for the presence, site, and pattern of discoid lateral meniscal tear, including type of displacement of the torn segment. MR abnormalities were correlated with arthroscopic findings. RESULTS: For the prospective MR interpretations, the PPV for discoid meniscus was 92%. PPV for discoid meniscal tear was 57%. PPVs for individual types of discoid meniscal tears were 46% (peripheral tear, 19/41), 76% (peripheral tear with horizontal tears, 16/21), 56% (horizontal tear, 5/9), 50% (transverse tear, 1/2), 67% (horizontal tear combined with transverse tear, 2/3), and 100% (longitudinal tear, 1/1). Peripheral tear alone and peripheral tear with horizontal tear were the most common types of tears (n = 20, 28%). Multiple tears (n = 34, 48%) were common. Displacement of the torn segments was seen in 51 patients (72%). CONCLUSION: MR imaging has a low PPV for diagnosing discoid lateral meniscal tear. Peripheral tear alone and peripheral tear with horizontal tear were the most common types of tears, and displacement of the torn segment was frequent.     

Clinical and sonographic meniscus diagnosis

Clinical examination still plays an important role in diagnosing meniscal tears. The types of sensitive nerves in the knee joint are responsible for nonspecific pain, which is often correlated with too little specificity in meniscal tests. Ultrasound examination of meniscal structures of the knee joint has been debated extensively in recent years. Criticism of this noninvasive technique was due to small patient groups, improper technical and inaccurate manual standards. Since 1988 ultrasound of the tibial meniscus has become a standard technique in our Department of Orthopaedic Surgery with defined criteria of the intersecting plane and evaluation of ultrasound images. A prospective follow-up study during 6/1988 and 5/1993 including 1186 ultrasound examinations before arthroscopy, was performed. The sensitivity for ultrasound of the lateral meniscus was 58% and for the medial meniscus 83%. Specificity with 98% for the lateral and 90% for the medial meniscus was good. Sonographic detection of meniscal tears depends on the shape and location of meniscal tears. This has been shown by experimental studies in cadavers. A follow-up study including 113 knee joints was performed to prove the value of clinical and ultrasound examination in relation to arthroscopy. The sensitivity of sonography for medial meniscus was 81% and 40% for the lateral meniscus. Although the sensitivity of the clinical examination was 81% (medial) and 47% (lateral), the low specificity of 70% for meniscus tears indicated that it was because of false-positive clinical evaluation of meniscal disorders. In young patients with reflectory muscle spasm and those with acute trauma of the knee joint, clinical examination of the meniscal structures showed poor results. In these cases, too, ultrasound examination showed advantages. Ultrasound of the knee joint meniscus is noninvasive, reproducible and low cost. In cases of uncertain clinical results, ultrasound offers a good opportunity to visualize meniscal disorders.     

Influence of magnetic resonance imaging on indications for arthroscopy of the knee

In a prospective study, magnetic resonance imaging was performed before arthroscopy for all patients (n = 121) with a meniscal tear (n = 125). Criteria of the study were stable cruciate and collateral ligaments, absence of pathologic radiographic findings, and absence of prior surgical interventions of the involved knee joint. In 43 knees (34%), the clinical diagnosis of a meniscal tear was discarded because of the results of the magnetic resonance imaging examination. Synovitis was diagnosed in 16 patients (13%), articular cartilage damage in 10 patients (8%), bone bruise injuries in 10 patients (8%), osteochondritis dissecans in 3 patients (2%), disruption of the inner layer of the medial collateral ligament in 3 patients (2%), and osteonecrosis in 1 patient. The use of magnetic resonance imaging in establishing diagnosis of disorders of the knee joint altered treatment in a significant proportion of patients. Magnetic resonance imaging should be done before arthroscopy of the knee in all cases in which the clinical diagnosis has been reduced to a suspected meniscus injury.     

Arthroscopy: possibilities and limitations in the diagnosis and therapy of meniscus lesions

The menisci consist of fibrocartilage and are an important supporting structure of the knee joint. They are poorly vascularized and have to withstand a high mechanical strain and load; therefore, lesions are common, especially on the medial side. Meniscal lesions are among the most frequent surgical procedures in orthopedic surgery. Meniscal lesions are diagnosed by a careful clinical examination in 80% of all cases in spite of modern imaging techniques such as magnetic resonance imaging (MRI). In the last 15 years, arthroscopic meniscectomy has become the 'golden standard' of therapy. Arthroscopy provides a powerful tool to precisely locate and classify the type of meniscus injury and to perform arthroscopic meniscectomy at the same time. This means less morbidity, reduced hospitalization time and earlier return to work and hence reduced costs. The endoscopic technique allows to exactly remove the damaged parts of the meniscus with precision instruments (partial meniscectomy). Former open techniques only allowed the complete removal of the meniscus. The arthroscopic techniques used nowadays allow a preservation of the functionally important edge of the meniscus, which is responsible for the stability and the biomechanics of the knee joint and can thus prevent an early onset of arthrosis. In rare cases of peripheral meniscal tears in young patients, arthroscopic refixation is an advantageous treatment option. Partial arthroscopic meniscectomy and arthroscopic meniscus refixation are challenging therapeutic procedures that require a trained and experienced orthopedic surgeon. Today diagnostic arthroscopy is more and more abandoned in favour of noninvasive and reliable MRI techniques. MRI is also useful in cases of previous knee surgery and clinically unclear findings, but should not be used on a routine basis. In differential diagnosis, the orthopedic surgeon always has to evaluate the MRI findings as to their impact. Today, arthroscopic knee surgery is a reliable, technically sophisticated and standardized technique to treat meniscal damages of all patients. There is a relatively low rate of complications, provided that the indication for the procedure is critically applied and restricted to patients with sufficient clinical and MRI findings.     

Tunneled hemodialysis catheters: use of a silver-coated catheter for prevention of infection--a randomized study

OBJECTIVE: The purpose of this study was to determine the feasibility of high-resolution sonography for the detection of meniscal cysts and associated meniscal tears and for the differentiation of meniscal cysts from other masses at the knee joint. SUBJECTS AND METHODS: Fifty consecutive patients (51 knees) with a palpable mass at the knee joint were examined prospectively using a 7.5-MHz annular array transducer. Mass consistency and location and meniscal integrity were evaluated. Sonographic findings were correlated with surgery (46/51) and histopathology (15/51). Five patients did not undergo surgery. RESULTS: At surgery, 32 masses appeared to be meniscal cysts, whereas 19 were other types of masses. Sonographically, 31 of the 32 meniscal cysts were diagnosed correctly. Sonographic differentiation of the other types of masses from meniscal cysts could reliably be made in 17 of 19 cases; two masses were falsely interpreted as meniscal cysts. Sensitivity, specificity, and accuracy of sonography in the depiction of meniscal cysts were 97%, 86%, and 94%, respectively. The positive predictive value was 94% and the negative predictive value was 92%. Meniscal tears (31/46) and meniscal tears concomitant with meniscal cysts (26/32) were detected with an accuracy of 83% and 88%, respectively. CONCLUSION: Sonography is an accurate imaging technique for the detection of meniscal cysts and associated meniscal tears. Differentiation of meniscal cysts from other cystic and solid masses at the knee joint can be reliably made with sonography.     

Accuracy of direct signs of tears of the anterior cruciate ligament

OBJECTIVE: To evaluate the accuracy of direct magnetic resonance imaging (MRI) signs of tears of the anterior cruciate ligament. PATIENTS AND METHODS: Over the period April 1991 to February 1994, 92 consecutive MRI studies of the knee were obtained for which arthroscopic data were also available. The MRI studies were retrospectively evaluated for course, continuity, signal intensity, morphologic features, contour and visualization of the anterior cruciate ligament. Arthroscopic findings were correlated with individual primary signs and the overall MRI diagnosis. RESULTS: Among the cases studied were 4 partial and 32 complete tears of the anterior cruciate ligament (as determined by arthroscopy). Because of the low number of partial tears, it was not possible to draw any meaningful conclusions about the MRI diagnosis of this type of tear. For complete tears, the criteria with the highest accuracy were abnormal course of the ligament (96.0%) and high signal intensity (89.3%). The overall diagnostic accuracy of MRI was 98.8%. CONCLUSIONS: The most accurate direct MRI finding in patients with a complete tear of the anterior cruciate ligament was abnormal course of the ligament, followed by abnormally high signal intensity.     

Magnetic resonance imaging assessment of the rotator cuff: is it really accurate?

Magnetic resonance imaging (MRI) is used increasingly for evaluating the rotator cuff. This study of 39 shoulders (38 patients) compared the accuracy of MRI interpretation of rotator cuff integrity by a group of community hospital radiologists (clinical community scenario, CCS) with that of a musculoskeletal radiologist (experienced specialist scenario, ESS), relative to arthroscopy. For the CCS subgroup, the sensitivity, specificity, positive predictive value (PV), negative PV, and accuracy for partial tears were: 0%, 68%, 0%, 82%, and 59%, respectively; for complete tears: 56%, 73%, 36%, 86%, and 69%, respectively; and for all tears combined: 85%, 52%, 50%, 87%, and 64%, respectively. For the ESS subgroup, the respective values for partial tears were: 20%, 88%, 20%, 88%, and 79%, respectively; for complete tears: 78%, 83%, 58%, 92%, and 82%, respectively; and for all tears: 71%, 71%, 59%, 81%, and 71%, respectively. We concluded that MRI assessment of the rotator cuff was not accurate relative to arthroscopy. MRI was most helpful if the result was negative, and MRI diagnosis of partial tear was of little value. Considering the high cost of shoulder MRI, this study has significant implications for the evaluation of patients with possible rotator cuff pathology.     

Indirect MR arthrography of the shoulder. An alternative to direct MR arthrography?

INTRODUCTION: The purpose of this study was to evaluate the diagnostic power of indirect MR arthrography (I-MRA) particularly in rotator cuff tears. MATERIAL AND METHODS: Sonography, conventional MRI and I-MRA were compared with arthroscopy in 25 patients. Additionally literature about experience with the method in other shoulder disease was searched. RESULTS: Sensitivity and specificity in the detection of rotator cuff tears were 0.6 and 0.7 respectively using sonography, 0.66 and 1 with conventional MRI and 1 and 0.86 for I-MRA. I-MRA was especially useful in diagnosing partial tears. In other studies I-MRA showed good results in the evaluation of glenoid labral tears, with a sensitivity of 91% and a specificity of 92%. CONCLUSION: I-MRA can be successfully used to diagnose rotator cuff and labral tears.     

Correlation of MRI and arthroscopic diagnosis of knee pathology in children and adolescents

The accuracy of magnetic resonance imaging (MRI) in diagnosing knee pathology in the pediatric and adolescent population is not well established. The purpose of this study was to correlate the findings of MRI and knee arthroscopy in children and adolescents. One hundred and eight consecutive knee arthroscopies performed in patients ages 4-17 years between 1992 and 1996 were retrospectively reviewed. Fifty-three of these patients underwent preoperative MRI. Age-related comparisons were then made between MRIs and observed intraoperative meniscal and anterior cruciate ligament pathology. The pediatric group (ages 4-14 years) was demonstrated to have an appreciable decrease in sensitivity, specificity, positive predictive value, and accuracy for essentially all categories of pathologic changes. Conversely, negative predictive values for the pediatric group exceeded those of the adolescent group (ages 15-17 years) in each category. The ability of MRI to predict intraarticular knee pathology among adolescents is comparable to that in adults, whereas it is much less accurate in the pediatric population.     

Tears of the medial collateral ligament: magnetic resonance imaging findings and associated injuries

For 23 patients with a surgically proven tear of the medial collateral ligament the findings from magnetic resonance imaging (MRI) of the knee were evaluated retrospectively. MRI revealed the tear in all cases, although when the injury was severe, distinguishing high-grade partial tears from complete tears was difficult. Physical examination had indicated a tear in 22 (96%) of the cases. A high prevalence of associated cruciate and meniscal injuries was seen (in 23 [100%] and 12 [52%] of the cases respectively). Tears of the fibular collateral ligament occurred in 13 (57%) of the patients and at least one bony infraction in 22 (96%); most of the infractions were in the lateral compartment. Infractions of the lateral femoral condyle were frequently geographic (in 14 [70%] of the 20 cases) or impacted (in 5 [25%]). The spectrum of injuries associated with tears of the medial collateral ligament was consistent with the findings of previous studies focusing on cruciate and meniscal abnormalities; the minor variations were likely due to the severity of valgus stress in this sample.     

Selection of the optimal nonexercise stress for the evaluation of ischemic regional myocardial dysfunction and malperfusion. Comparison of dobutamine and adenosine using echocardiography and 99mTc-MIBI single photon emission computed tomography

BACKGROUND: The mechanisms of action of exercise-simulating and vasodilator stressors support their combination with imaging techniques that evaluate left ventricular function and perfusion, respectively. However, reported accuracies of either pharmacological stress together with two-dimensional echocardiography (2DE) or single photon emission computed tomography (SPECT) of myocardial perfusion are similar. The purpose of this study was to establish the optimal stress for each imaging technique by comparing the results of digitized 2DE and 99mTc-methoxyisobutyl isonitrile (MIBI) SPECT using both dobutamine and adenosine stresses in the same patients and conditions. METHODS AND RESULTS: Ninety-seven consecutive patients without evidence of previous infarction undergoing coronary angiography for clinical indications were studied prospectively. Dobutamine was infused during clinical, ECG, and echocardiographic monitoring in dose increments from 5 to 40 micrograms.kg-1.min-1. Adenosine was infused under the same conditions in doses of 0.10, 0.14, and 0.18 mg.kg-1.min-1. For each protocol, the end points were achievement of peak dose, development of severe ischemia, or intolerable side effects. At peak stress, 20 mCi of MIBI was injected, and SPECT imaging was performed 2 hours later; abnormal poststress images were compared with resting SPECT: Digitized 2DE images were compared qualitatively before, during, and after stress in a cine-loop display. Significant coronary disease (n = 59 patients) was defined by the quantification of > 50% stenosis in a major epicardial vessel. The sensitivity of adenosine 2DE was 58%, less than those of adenosine MIBI (86%, p = 0.001), dobutamine 2DE (85%, p = 0.001), and dobutamine MIBI (80%, p = 0.01). Their respective specificities were 87%, 71%, 82%, and 74% (p = NS). The accuracy of adenosine 2DE was 69%, compared with 80% for adenosine MIBI (p < 0.001), 84% for dobutamine 2DE (p = 0.001), and 77% for dobutamine MIBI (p = 0.005); the latter three did not differ significantly in either sensitivity or accuracy. CONCLUSIONS: This prospective, direct comparison of alternative pharmacological stresses in patients without myocardial infarction shows vasodilator stress scintigraphy and dobutamine stress echocardiography and scintigraphy to share equivalent levels of sensitivity. All three are significantly more sensitive than adenosine stress echocardiography. Dobutamine stress may be used for wall motion or perfusion imaging, but adenosine stress is best combined with perfusion scintigraphy.     

Intermediate-term results of meniscal repair in anterior cruciate ligament-reconstructed knees

We investigated the incidence of and risk factors for recurrent tears of repaired menisci in anterior cruciate ligament-reconstructed knees. We observed 63 patients whose menisci had been evaluated at second-look arthroscopy as healed (N = 50) or incompletely healed (N = 13) for an average of 4 years (range, 2 to 9.5). Of the 13 patients with incompletely healed menisci, 6 (46%) required additional meniscal surgery and 2 (15%) had recurrence of meniscal symptoms such as catching or locking. Among the 50 patients with healed menisci, 5 (10%) required additional meniscal surgery and 9 (18%) had recurrence of meniscal symptoms after second-look arthroscopy. The timing of the recurrence of these symptoms was from 12 to 28 months after surgical repair. Of the 11 patients who had undergone additional surgery, 6 had sustained second injuries during sports activities and the other 5 had no identifiable cause of injury. When comparing age, tear sites, rim width, side-to-side differences with KT-1000 arthrometer testing, and the pivot shift test, there were no differences between the group requiring additional surgery, the symptomatic group, and the asymptomatic group. However, the postoperative Tegner activity score of the group requiring additional surgery was statistically significantly higher than the others.     

Meniscal injuries associated with acute anterior cruciate ligament tears in alpine skiers

We reviewed the records of 315 patients receiving an arthroscopically assisted stabilizing procedure for an acute anterior cruciate ligament injury incurred while alpine skiing to evaluate associated meniscal injuries. Meniscal injuries were classified by type, location, and treatment of the tear. Of the 317 knees operated on, all demonstrated an anterior cruciate ligament tear at arthroscopy. Ninety-eight percent of the injuries (310) were diagnosed within 3 days of injury, and 97% (307) were reconstructed within 28 days of injury. All tears occurred in the intrasubstance of the ligament; 32% were isolated injuries and 68% were combined with other injuries. In 159 patients with 170 meniscal tears 141 of the tears (83%) were lateral and 29 (17%) were medial. The injury triad of anterior cruciate ligament-medial collateral ligament-lateral meniscus was seen nine times as often as the anterior cruciate ligament-medial collateral ligament-medial mensicus combination.     

Magnetic resonance imaging of knee injuries in children

The appearances of knee injuries on MR imaging are less well documented in children than adults. Some patterns of injury are shared by both groups of patients, e. g. meniscal damage. The frequency of specific injuries may differ, e. g. anterior cruciate ligament (ACL) tear. Congenital abnormality, coexistent pathology and previous treatment of the knee appear to be associated with meniscal problems. Discoid menisci are seen most frequently in children and have unique features on MR scans. Cruciate ligament tears are difficult to diagnose in the smallest children. The ACL may not be identified due to its small size. Normal bone marrow signal may be confused with marrow infiltration or bone microfracture. Radiographically occult fractures around the knee appear to be strongly associated with ligamentous injury as in adult patients. Osteochondral fractures, osteochondral lesions and articular cartilage damage are revealed on MR scans, but their long-term effects are uncertain. It is possible to diagnose a range of knee injuries on MR scans in children. The biggest diagnostic challenge is in pre-school children.     

Chondrocalcinosis of the hyaline cartilage of the knee: MRI manifestations

PURPOSE: To determine the ability of MRI to detect the presence of crystals of calcium pyrophosphate in the articular cartilage of the knee. DESIGN AND PATIENTS: The MR studies of 12 knees (11 cases) were reviewed retrospectively and correlated with radiographs (12 cases) and the findings at arthroscopy (2 cases) and surgery (1 case). A total of 72 articular surfaces were evaluated. Radiographic, surgical or arthroscopic demonstration of chondrocalcinosis was used as the gold standard. Additionally, two fragments of the knee of a patient who underwent total knee replacement and demonstrated extensive chondrocalcinosis were studied with radiography and MRI using spin-echo T1-, T2- and proton-density-weighted images as well as two- and three-dimensional fat saturation (2D and 3D Fat Sat) gradient recalled echo (GRE) and STIR sequences. RESULTS: MRI revealed multiple hypointense foci within the articular cartilage in 34 articular surfaces, better shown on 2D and 3D GRE sequences. Radiographs showed 12 articular surfaces with chondrocalcinosis. In three cases with arthroscopic or surgical correlation, MRI demonstrated more diffuse involvement of the articular cartilage than did the radiographs. The 3D Fat Sat GRE sequences were the best for demonstrating articular calcification in vitro. In no case was meniscal calcification identified with MRI. Hyperintense halos around some of the calcifications were seen on the MR images. CONCLUSION: MRI can depict articular cartilage calcification as hypointense foci using GRE techniques. Differential diagnosis includes loose bodies, post-surgical changes, marginal osteophytes and hemosiderin deposition.     

Usefulness of magnetic resonance imaging for detecting intrasubstance tear and/or degeneration of lateral discoid meniscus

In order to determine the usefulness of magnetic resonance imaging (MRI) for detection of intrasubstance tears or degeneration of the lateral discoid meniscus, we compared findings obtained with MRI with those of histological examination. Sixty-four symptomatic lateral discoid menisci were studied using MRI before surgical treatment. Of these, 18 (28%) met the criteria that MRI signals did not extend to the surface and that no visible tears were observable at arthroscopy. Findings of intrameniscal regions of high signal intensity and flattening in shape on MR images were found to represent intrasubstance tears or degeneration not detected at arthroscopy. Our findings thus demonstrate that MRI is more sensitive than arthroscopy in the detection of intrasubstance pathologies of the lateral discoid menisci.