The effect of intra-articular gadolinium-DTPA on synovial membrane and cartilage.

This investigation evaluated the potential effect of gadolinium (Gd)-DTPA-dimeglumine on synovial membrane and joint cartilage, using macroscopic, microscopic, and x-ray fluorescent spectroscopic techniques. Thirteen New Zealand white rabbits (26 knees) were used in this study, ten receiving 500 micromolar injections of Gd-DTPA-dimeglumine in their right knees; the remainder of the knees served as controls. One injected knee had minimal joint effusion and one had mild hyperemia. Microscopically four knees exhibited mild focal hyperplasia of the synovium, another three minimal focal mononuclear cell infiltration. X-ray fluorescent spectroscopy demonstrated no evidence of Gd-DTPA-dimeglumine in the synovium or articular cartilage. Neither macroscopic nor microscopic evaluation detected any Gd-DTPA-dimeglumine related effects. Gd-DTPA-dimeglumine was found to be safe for intra-articular injection in this animal model.

MRI in the evaluation of patients with suspected instability of the shoulder joint including a comparison with CT-arthrography.

Thirty-two patients with clinical suspicion of shoulder instability were the subject of this assessment of MRI (1.5 T G. E. Signa) and its comparison with CT-arthrography (GE8800 and GE9800) of the shoulder. Twenty-seven patients had a final diagnosis established by arthroscopy and five by arthrotomy. The imaging examinations were interpreted independently by three radiologists blinded against history, surgical diagnosis and results of the compared test. The statistical analysis included ROC-curves, sensitivity, specificity and accuracy as well as predictive values. The significance of the comparative results was assessed by the McNemar Sign test. MRI showed significantly better diagnostic results in the evaluation of labral structures (sensitivity 85%, specificity 90%, accuracy 88%) and humeral head impression fractures (75, 82, 78 %). None of the tests were of sufficient diagnostic value to identify capsular abnormalities. CT and MRI results regarding the biceps tendon and loose bodies were similar, however, statistically not significant. MRI proved to be of high diagnostic value in the assessment of the unstable shoulder and compared favorably with CT-A.

Granulomatous tenosynovitis: a rare musculoskeletal manifestation of tuberculosis.

A patient with tenosynovial tuberculosis affecting the extensor tendons of the wrist and hand is presented. This case highlights the clinical and magnetic resonance features of tuberculous tenosynovitis, and seeks to increase awareness of what may represent a resurgent musculoskeletal entity.

MRI of the knee in diffuse pigmented villonodular synovitis.

Magnetic resonance imaging (MRI) was performed on 11 patients with surgically proven pigmented villonodular synovitis (PVNS) of the knee. PVNS was diagnosed on the basis of presence of hemosiderin, joint effusion, and hyperplastic synovium without significant joint destruction. MRI provided a detailed map of the distribution of the disease within the joint, emphasizing the common occurrence of the disease behind the cruciate ligaments and in synovial cysts in the popliteal fossa. MRI aided in preoperative planning and postoperative follow-up for residual and recurrent disease. Nine additional cases of joint hemorrhage, hemophilia, desmoplastic tumors, and synovial chondromatosis were included to delineate differential diagnostic criteria.

CT of the pancreatic tail.

The location of the pancreatic tail varies and is confined only by the limits of the anterior pararenal space and the left kidney. The morphology of the pancreatic tail and its location relative to the upper pole of the left kidney, the body of the pancreas, and the splenic hilum were assessed by body computed tomography in 101 patients with normal kidneys and in 15 patients with either small or absent left kidneys. In 97% of normal patients, the pancreatic tail was located anterior or anterolateral to the left kidney. In 75% of patients with surgically or congenitally absent kidneys, the pancreatic tail lay dorsomedial, adjacent to the spine, and occupied, with bowel and spleen, the empty renal fossa. Variation in pancreatic tail location may be of diagnostic importance in patients suspected of having mass lesions in the left mid-abdomen.

[Pancreas tail pseudotumor--CT for the detection of position variants of the pancreas tail as a cause for pathologic findings in conventional radiographic and ultrasound studies]. / Pankreasschwanz-Pseudotumor--CT zum Nachweis einer Lagevariante des Pankreasschwanzes als Ursache für pathologische Befunde bei konventionellen radiographischen und Ultraschalluntersuchungen.

Four cases are presented, in whom conventional radiography of the abdomen including tomography and ultrasound raised high suspicion of a left suprarenal tumor. Abdominal CT explained the finding in each case as being produced by a normal anatomic variation of the pancreatic tail, which was found in a paraspinal and suprarenal location. The statistical incidence of such a variation is discussed.

Fetal biometry and intrauterine growth retardation. Current concepts.

Monitoring fetal growth and detecting intrauterine growth retardation comprise a large percentage of the reasons for ultrasound examinations. Detecting intrauterine growth retardation can significantly reduce perinatal mortality and is facilitated by calculations of numerous fetal measurements.

Gastroesophageal reflux--reassessment of the value of fluoroscopy based on manometric evaluation of the lower esophageal segment.

The value of fluoroscopic gastroesophageal reflux examination by barium swallow was assessed in 51 symptomatic patients. Using electronic esophageal manometry, these patients were divided in groups with frank reflux, intermittent reflux, and symptoms of other etiology. Although a high incidence between presence of an hiatal hernia and manometric reflux (0.86) was apparent, fluoroscopy was only able to identify 33% of patients suffering from reflux disease diagnosed on clinical grounds and by electronic manometry. It is concluded that the fluoroscopic test is insufficient to separate patients with reflux disease from those with similar symptoms of other etiology which may be done reliably by esophageal manometry. The role of fluoroscopy is limited to the morphological evaluation of the gastroesophageal junction.

MR imaging of the labral-capsular complex: normal variations.

Understanding the normal anatomy of the shoulder and its variations is important for the proper interpretation of MR images. This study was performed to describe variations in the normal labral-capsular complex as seen on MR images. MR images of 52 shoulders in 30 asymptomatic volunteers and 27 shoulders of symptomatic patients who had subsequent arthroscopy and/or reconstructive surgery were obtained with 1.5-T MR. The 52 scans of the asymptomatic group were reviewed by three radiologists in conference, and the assessment of labral shapes and capsular insertions was done by consensus. The 27 MR scans of the shoulders in the symptomatic group were reviewed by one radiologist before and after the asymptomatic cases were interpreted. Differences in these two interpretations were shown on receiver-operating-characteristic curves by using the results of subsequent arthroscopy and surgery as the gold standard. The anterior and posterior parts of the labra, respectively, varied in shape but showed several dominant features: triangular (45%, 73%), round (19%, 12%), cleaved (15%, 0%), notched (8%, 0%), flat (7%, 6%), and absent (6%, 8%). Most capsules inserted anteriorly on the labrum (47%) or glenoid rim (49%). All posterior insertions were on the labrum (100%). Intrinsic labral signal was noted on proton density-weighted images, but never on T2-weighted images. Receiver-operating-characteristic curves from interpretations of the symptomatic and clinical cases made before and after evaluation of the asymptomatic shoulders showed the interpretations improved considerably after scans of asymptomatic volunteers were studied. Our study reveals a wide variability in the MR appearance of the labral-capsular complex in asymptomatic shoulders.

Aortic dissection: CT and angiographic comparisons.

Computed tomography and aortography were compared in a retrospective study of 35 patients with aortic dissection of type A (n = 17) and type B (n = 18). Based on classical diagnostic criteria such as evidence of two channels, intimal flaps and displaced intimal calcification, computed tomography was able to confirm the presence and type of aortic dissection in 32 patients. Dynamic computed tomography was used in 20 cases. When bolus technique was applied appropriately (16/20), computed tomography clearly differentiated the two channels and identified each by its time density characteristics. In 5 of the 35 patients included, the aortographic diagnosis was equivocal because no definite second channel was identified. In these, CT was helpful to confirm the diagnosis showing the presence of an intimal flap, displaced intimal calcification and clot in the false channel. It was noted that classical signs of differentiation of the true and false channels by their relationship to intimal calcification and by the anatomic relationship of the two identified channels to each other at different levels of the aorta are not without exceptions. It is concluded that dynamic computed tomography represents a valuable alternative to aortography and is preferred in chronic dissection and follow-up examinations and for the initial workup of patients with a mediastinal mass. However, when a roadmap of the aortic branches is required prior to surgical intervention, aortography remains the procedure of choice.

The temporomandibular joint: true sagittal computed tomography with meniscus visualization.

Accessory patient support equipment was constructed that allows patient positioning for true sagittal projection of the temporomandibular joint using a GE 8800 CT/T scanner. Range of motion abnormalities, osseous alterations of the mandibular condyle and temporal bone, joint-space narrowing, and meniscal configuration may be demonstrated. The technique has potential advantages over other CT projections and sagittal reconstruction for evaluation of temporomandibular joint dysfunction.

The coracoacromial arch: MR evaluation and correlation with rotator cuff pathology.

The relative prevalence of various acromial shapes, appearance of the coracoacromial ligament and enthesophytes along the inferior aspect of the acromioclavicular joint in patients with and without rotator cuff tears were evaluated. Of 76 patients with clinical instability and impingement, 31 had a normal rotator cuff and 45 demonstrated a partial or full tear of the supraspinatus tendon at surgery. Results were compared with those from magnetic resonance (MR) scans of 57 asymptomatic volunteers. Of the 45 patients with a supraspinatus tear, 38% (17) had a flat acromial undersurface (type I), 40% (18) had a concave acromial undersurface (type II), 18% (8) had an anteriorly hooked acromion (type III), and 4% (2) had an inferiorly convex acromion (type IV). Among the 31 patients with a normal rotator cuff at surgery and the 57 asymptomatic volunteers, the respective prevalences of the type I acromion were 39% (12) and 44% (25), of type II 48% (15) and 35% (20), type III 3% (1) and 12% (7), and type IV 10% (3) and 9% (5). Shoulders with surgically proven rotator cuff tears showed a tendential association with a type III acromion (8/45) and statistically significant associations with a thickened coracoacromial ligament (17/45) and acromioclavicular enthesophytes (18/45). For the association between inferiorly directed acromioclavicular joint enthesophytes and rotator cuff tears, age appears to be a confounding factor. The type IV acromion, newly classified by this study, does not have a recognizable association with rotator cuff tears.(ABSTRACT TRUNCATED AT 250 WORDS)

Clinical value of ultrasonography for the management of non-Hodgkin lymphoma patients as compared with abdominal computed tomography.

In 50% of 84 ultrasonographic (US) examinations ordered for staging and restaging of non-Hodgkin lymphoma (NHL) patients, the abdomen and pelvis were not sufficiently visualized to allow diagnostic conclusions, whereas nondiagnostic studies were found in only 3% of the 102 computed tomographic (CT) examinations. Discrepancy about the presence and extent of disease below the diaphragm between US and CT occurred in 74%. The US underestimated the presence or extent of disease in nodal stations caudal to the pancreas more commonly than in other areas evaluated. Because of increased cost, patient inconvenience, and delay in therapeutic intervention due to repeat examinations, it is recommended that CT be used as the initial examination for staging, restaging, or following infradiaphragmatic disease in NHL patients.

Potential contrast agents for MR arthrography: in vitro evaluation and practical observations.

In an attempt to identify an ideal contrast agent for MR arthrography, signal behavior as well as T1 and T2 values for articular cartilage, menisci, and ligaments were determined in knees from cadavers and normal volunteers. Comparison was made with similar data derived for intraarticular blood, varying concentrations of an albumin-saline solution (simulating synovial fluid) and Gd-DTPA, 0.9% saline, Renografin 60%, and air. Cadaveric specimens were imaged after intraarticular administration of each substance. A 500-microM volume of Gd-DTPA proved to be an ideal contrast agent for MR arthrography, exhibiting excellent contrast differences with articular structures on T1-weighted images. An albumin concentration of 12%, potentially occurring in severe inflammatory arthritis, also manifested adequate contrast to articular cartilage on T1-weighted images. Renografin and saline provided inadequate contrast on T1-weighted images, and saline necessitated the use of T2-weighted sequences. Air was not found to be an optimal contrast agent. Intraarticular blood exhibited insufficient contrast differences with articular cartilage during the acute hemorrhagic phase. Synovial fluid associated with severe arthritis as compared with fresh intraarticular hemorrhage may thus prove to be a better biological contrast agent for MR arthrography. Saline is currently recommended for use in arthrography, but Gd-DTPA offers significant advantages and should be safety-tested for potential clinical use.

MR arthrography: anatomic-pathologic investigation.

To enhance the efficacy of magnetic resonance (MR) imaging in evaluating articular soft-tissue structures, arthrography was performed before imaging 45 fresh cadaveric specimens. Contrast agents used were gadolinium-DTPA, 0.9% saline, diatrizoate, and air. MR imaging was performed with and without intraarticular contrast material, and specimens were subsequently sectioned in the same plane. Gd-DTPA was the most effective agent. Saline and diatrizoate exhibited equivalent signal behavior and necessitated T2-weighted sequences, while air was not useful. Depiction of normal anatomy was enhanced with MR arthrography. After surgical creation of lesions in selected specimens, subtle tears were delineated exclusively with MR arthrography, and major tears were diagnosed more confidently. Intraarticular contrast material may enhance the diagnostic capabilities of MR imaging in the setting of joint disease.

Gadopentetate-enhanced magnetic resonance imaging with fat saturation in the evaluation of Morton's neuroma.

Morton's neuromas, though usually diagnosed clinically, can occasionally be problematic. When required, imaging may be performed via ultrasound or computed tomography, though the former can be quite operator-dependent, and the latter exposes the patient to ionizing radiation. Magnetic resonance imaging can be very helpful in certain clinical situations. This case report demonstrates the usefulness of gadopentetate-enhanced magnetic resonance imaging with fat saturation in the evaluation of interdigital neuromas.

Computed tomography of the abdomen and pelvis in non-Hodgkin lymphoma.

The experience of one institution using abdominal computed tomography (CT) for staging and restaging of non-Hodgkin lymphoma (NHL) patients is reported. In 49% of abnormal examinations no significant difference in quantity of involved nodes between diffuse and nodular lymphomas appeared. High paraaortic, iliac, and mesenteric nodal sites were most commonly involved. At restaging examination, usually less extent of disease was found. Abdominal involvement could not be predicted from the presence of peripheral adenopathy. Computed tomography changed the staged during initial workup significantly in 14%. During restaging, CT detected unsuspected active disease in 43% and changed the clinical impression from limited to extensive involvement in 16%. Computed tomography proved to be useful in the management of NHL patients and is recommended as the primary imaging procedure in the abdomen in this disease.

Lateral tibial rim (Segond) fractures: MR imaging characteristics.

The magnetic resonance (MR) imaging characteristics of lateral tibial rim (Segond) fractures and their associated injuries were reviewed in 12 patients with radiographic evidence of this fracture. Bone marrow adjacent to the fracture emitted a focally abnormal MR signal, which indicated an injury of the lateral capsular junction. The Segond fragment, however, was seen on MR images in only four of 12 patients. Associated ligamentous and meniscal injuries identified with MR imaging and arthroscopy involved the anterior (n = 11) and medial (n = 7) cruciate ligaments and the lateral (n = 4) and medial (n = 1) menisci. Focal bone marrow edema was due to injury of the lateral capsular junction. MR imaging evidence of such edema should indicate the presence of a lateral capsular injury and fracture, if one has not already been demonstrated with conventional radiography. A high association of Segond fractures with tears of the anterior cruciate ligament was confirmed, and MR imaging signs of a Segond fracture may therefore be used as indirect evidence for tears of that ligament.

High-resolution magnetic resonance imaging of the ankle: normal anatomy.

An imaging-anatomic correlative study of ankle anatomy based upon six healthy adults and six fresh cadaveric specimens was performed to evaluate the diagnostic capabilities of magnetic resonance imaging (MRI). Optimal pulsing sequences and imaging planes for various structures of interest were established. MRI afforded exquisite depiction of anatomic detail, particularly the diagnostically important collateral ligaments. Limitations in the ability to delineate the joint capsule and articular cartilage were documented, with the former detectable only on T2 weighted images in the presence of synovial fluid.

Meniscal tears: MR and arthrographic findings after arthroscopic repair.

Magnetic resonance (MR) imaging was performed on 29 previously repaired menisci and one conservatively treated meniscus (total, 30 menisci). Intermediate- and T1-weighted MR sequences revealed persistent signal intensity extending to an articular surface (grade 3 signal intensity) in 27 of the 30 menisci. On T2-weighted images, seven of the 30 menisci were found to contain unequivocally higher signal intensity, defined by a full-thickness defect (grade 3 signal intensity involving two articular surfaces) increasing in signal intensity to a level equivalent to that of joint fluid. The MR imaging and arthrographic appearances of 23 of the 30 menisci were compared. Arthrographic examination revealed partial or complete healing in 13 menisci and tears in 10. The presence of grade 3 signal intensity on intermediate- and T1-weighted MR images did not reliably predict a tear seen at arthrography. Unequivocally higher signal intensity on T2-weighted images is a useful sign in the prediction of a persistent meniscal tear (sensitivity, 60%; specificity, 92%; P less than .02). Since presence of grade 3 signal intensity on intermediate- and T1-weighted images does not reliably predict a tear and unequivocal T2 increase in intensity has a sensitivity of only 60%, arthrography should be considered for assessment of the symptomatic, previously repaired meniscus.