Benign (BI-RADS 2) lesions in breast MRI.

AIM: To assess the frequency of malignancy in lesions characterized as benign [Breast Imaging-Reporting and Data System (BI-RADS) 2] on breast MRI. MATERIALS AND METHODS: In this institutional review board-approved retrospective single-centre study, 1265 consecutive patients (mean age 50 ± 13 years), undergoing dynamic contrast-enhanced MRI (1.5 T) of the breast during a 6 year time period, were eligible. This study investigated the MRI characteristics and frequency of malignancy in 192 of these patients with breast lesions classified as BI-RADS 2. Examinations were read during clinical practice and classified according to the MRI BI-RADS lexicon. Based on the patient's and referring physician's preferences, lesions were either histopathologically verified or were subjected to both clinical and imaging follow-up of at least 2 years (range 2-9 years). Descriptive statistical metrics were calculated. RESULTS: According to the standard of reference, 0 of 192 (0%) lesions classified as BI-RADS 2 were malignant. Histopathology was available in 67 (34.9%) lesions and revealed benign findings exclusively. The remaining 125 (65.1%) lesions did not exhibit changes during the follow-up period and were, therefore, considered negative for malignancy. CONCLUSIONS: The frequency of malignancy in breast lesions classified as BI-RADS 2 is zero. As a consequence, breast biopsies are unnecessary in these cases.

The anatomy of the joint as a risk factor for Lisfranc dislocation and fracture-dislocation. An anatomical and radiological case control study.

he anatomy of the mortise of the Lisfranc joint between the medial and lateral cuneiforms was studied in detail, with particular reference to features which may predispose to injury. In 33 consecutive patients with Lisfranc injuries we measured, from conventional radiographs, the medial depth of the mortise (A), the lateral depth (B) and the length of the second metatarsal (C). MRI was used to confirm the diagnosis. We calculated the mean depth of the mortise (A+B)/2, and the variables of the lever arm as follows: C/A, C/B and C/mean depth. The data were compared with those obtained in 84 cadaver feet with no previous injury of the Lisfranc joint complex. Statistical analysis used Student's two-sample t-test at the 5% error level and forward stepwise logistic regression. The mean medial depth of the mortise was found to be significantly less in patients with Lisfranc injuries than in the control group. Stepwise logistic regression identified only this depth as a significant risk factor for Lisfranc injuries. The odds of being in the injury group is 0.52 (approximately half) that of being a control if the medial depth of the mortise is increased by 1 mm, after adjusting for the other variables in the model. Our findings show that the mortise in patients with injuries to the Lisfranc joint is shallower than in the control group and the shallower it is the greater is the risk of injury.

Bilateral orbital pseudotumour due to Ormond's disease: MR imaging and CT findings.

We present the MRI and CT findings in a 43-year old patient with bilateral orbital pseudotumour due to Ormond's disease.

[Diagnostic value of conventional roentgen image, computerized and magnetic resonance tomography in acute sprains of the foot. A prospective clinical study]. / Diagnostische Wertigkeit von Nativröntgen, Computer- und Magnetresonanztomographie beim akuten Hyperflexionstrauma des Fusses. Eine prospektive klinische Studie.

In order to gain satisfying results in the treatment of acute hyperflexion trauma to the foot, it is absolutely necessary to achieve an exact primary diagnosis because injuries to the tarsometatarsal joint are frequently missed primarily. Aim of this prospective clinical study was to evaluate the diagnostic reliability of conventional radiography, CT and MRI compared to each other. 75 consecutive patients after hyperflexion trauma to the foot were included. There were 47 males and 28 females with a mean age of 38 years. After admittance, pa-, lateral and 45 degrees oblique radiographs were taken as well as stress views in comparison to the contralateral foot. Furthermore, CT and MRI were performed in any patient. By conventional radiography, 48 metatarsal and 24 tarsal fractures were diagnosed as well as 17 cases of malalignment of the Lisfranc joint. Stress radiographies were not able to provide a more accurate diagnosis. By CT scans, however, 86 metatarsal and 74 tarsal fractures were detected. Moreover, we found malalignment in 31 and bony avulsions of Lisfranc's ligament in 4 patients. By MRI, finally, 85 metatarsal, 100 tarsal fractures and 31 cases of malalignment were diagnosed. Additionally, partial or complete tears of Lisfranc's ligament were depicted in 22 patients. The present study could clearly show the superiority of CT and MRI to conventional radiography in diagnosis of bony and ligamentous disorders of the Lisfranc joint. Therefore, extended diagnosis has to be demanded in all cases of hyperflexion trauma to the foot.

Sonographic evaluation of the thenar compartment musculature.

The thenar region was studied with ultrasonography in 10 healthy volunteers. All thenar muscles could be identified and their course followed entirely. In addition, their function could be assessed by scanning during unresisted or resisted active movements. Standard approach, normal appearance, and dynamic tests for each muscle are described.

Ultrasonographic localization of a displaced screw in the carpal canal. A case report.

We present a case of a 65-year-old patient with a surgically treated distal radius fracture. At 5-month follow-up, conventional radiography revealed breakage of the plate and a screw displaced into the volar soft tissue. Preoperative ultrasonography including dynamic assessment of the tendons showed the screw intratendinously as a hyperechogenic structure with repetitive echoes. This unusual localization was proven by surgery. Dynamic ultrasonography played an important diagnostic role in the localization of the loosened and displaced osteosynthetic material.

Conventional radiography, CT, and MR imaging in patients with hyperflexion injuries of the foot: diagnostic accuracy in the detection of bony and ligamentous changes.

OBJECTIVE: The goal of this study was to compare the capabilities of conventional radiography, CT, and MR imaging in revealing ligamentous and bony changes in patients after hyperflexion injuries. SUBJECTS AND METHODS: Forty-nine patients with hyperflexion injuries of the foot were included in our study. Conventional radiography, weight-bearing radiography, CT, and MR imaging were performed. All images were reviewed with respect to ligamentous and bony abnormalities and alignment alterations. Eleven patients with joint malalignment underwent surgery, which is considered the gold standard in these patients. Five patients with joint malalignment refused surgery. RESULTS: For all 49 patients, conventional radiographs revealed 33 metatarsal and 20 tarsal fractures. Eight patients presented with tarsometatarsal joint (Lisfranc's joint) malalignment. Weight-bearing radiographs showed joint malalignment in the same eight patients only. CT showed 41 tarsal fractures and 53 metatarsal fractures. Joint malalignment was evident in 16 patients. MR imaging revealed 41 metatarsal fractures and 18 metatarsal bone bruises. Tarsal bones were fractured at 39 sites and there were nine tarsal bone bruises. Metatarsal fractures were mostly localized in the second metatarsal bone; tarsal fractures, in the cuboid. Joint malalignment was evident in 16 patients; in 11 of these 16 patients, Lisfranc's ligament was disrupted. Surgery confirmed bony and ligamentous changes and joint malalignment in 11 patients. CONCLUSION: Conventional radiographs including weight-bearing images are not sufficient for routine diagnostic workup of patients with acute hyperflexion injuries of the foot. CT should serve as the primary imaging technique for such patients.

Giant liposarcoma of the esophagus: radiological findings.

This case of an esophageal liposarcoma illustrates a polypoid lesion within the esophagus that extended from the left pyriform sinus to the distal esophagus above the gastric cardia. Contrast-enhanced computed tomography (CT) and magnetic resonance imaging (MRI) showed an inhomogenously-enhancing intraluminal mass, while video-fluoroscopy revealed that the mass was adherent to the esophageal wall and was associated with esophageal dilatation and diminished peristalsis. This ninth reported case of esophageal liposarcoma is the first described where preoperative radiologic studies and endoscopy showed broad fixation of the tumor to the esophageal wall.

[Acute appendicitis in non-contrast spiral CT: a diagnostic luxury or benefit?]. / Akute Appendizitis im Nicht-Kontrast-Spiral-CT: diagnostischer Luxus oder Nutzen?

PURPOSE: To evaluate the diagnostic accuracy of thin collimated unenhanced spiral-CT in patients with clinically suspected acute appendicitis and to determine the impact on patient management and overall costs. METHOD: Unenhanced focussed appendiceal spiral-CT was performed in 56 patients (23 women and 33 men) with clinically suspected acute appendicitis. Scans were obtained from the L4 level to the symphysis pubis using 5 mm collimation, 7.5 mm table feed (pitch 1.5) and 4 mm increment without i.v., oral, or rectal contrast material. Prospective diagnoses based on CT findings were compared with surgical (and histopathological) results and clinical follow-up. The effect of spiral-CT on patient management and clinical resources was assessed. RESULTS: 29 patients (10 women and 19 men) underwent appendectomy. Unenhanced spiral-CT was an accurate imaging technique for the initial examination of patients with suspected acute appendicitis with a sensitivity of 95.4% and a specificity 100%, an accuracy of 98.2%, a positive predictive value of 100%, and a negative predictive value of 97.1%. In 27 patients with no evidence of acute appendicitis, an alternative diagnosis could be made in 24 patients by unenhanced spiral-CT. CONCLUSION: Unenhanced spiral-CT is an accurate test to diagnose or to exclude acute appendicitis. Routine appendiceal spiral-CT can improve medical care and reduce the overall costs for patients suspected of having acute appendicitis.

Echo-enhanced Doppler sonography of focal nodular hyperplasia of the liver.

Lesions of focal nodular hyperplasia are hypervascular, benign focal liver lesions whose differentiation from other focal liver lesions is of significant clinical relevance. The purpose of this study was to investigate the echo-enhancing agent SHU 508A (Levovist) in the evaluation of focal nodular hyperplasia with Doppler sonography. We examined 49 patients with 71 lesions of focal nodular hyperplasia in the liver with gray scale and power Doppler sonography. In all patients Levovist was administered intravenously in a concentration of 300 to 400 mg galactose per milliliter. Visualization of the feeding vessels and the vascularity of the lesions were evaluated, and the resistive indices in the feeders and the hepatic arteries were assessed. In comparison with unenhanced power Doppler sonography, echo-enhanced power Doppler sonography yields a higher sensitivity in the detection of the feeding artery (97% versus 82%) in focal nodular hyperplasia and in the depiction of the radial vascular architecture in such lesions, especially those located in the left lobe of the liver. Lesions less than 3 cm in diameter do not consistently show a characteristic vascular architecture with echo-enhanced Doppler sonography. The resistive index of the tumor-feeding artery (mean, 0.51 +/- 0.09) is significantly (P < 0.0001) lower than that of the hepatic artery (mean, 0.65 +/- 0.06) and decreases as the size of the focal nodular hyperplasia increases. The administration of Levovist may improve the signal-to-noise ratio and thus visualization of the vascular architecture in focal nodular hyperplasia. Lesions located in the left lobe of the liver, which commonly are subject to disturbing motion artifacts in color Doppler sonography, will significantly benefit from the administration of Levovist. Echo-enhanced power Doppler sonography, however, is not capable of depicting a characteristic vascular pattern in small (< or = 3 cm) lesions of focal nodular hyperplasia that would guarantee a specific diagnosis.

[Native spiral computerized tomography in patients with acute flank pain--sense or nonsense?]. / Nativ-Spiral-Computertomographie bei Patienten mit akutem Flankenschmerz--Sinn oder Unsinn?

PURPOSE: To compare the diagnostic efficacy and costs of native spiral-CT and intravenous urography (IVU) in the management of patients with acute flank pain. METHOD: Native spiral-CT and IVU (following about 30 minutes after CT) were compared in 66 patients with acute flank pain followed by an IVU. The spiral-CT protocol was: 5-mm section thickness, 7.5-mm table feed and 3-mm increment. The analysis conducted independently by two radiologists entailed: (a) Morphology: presence of stone disease (yes-no), localization and size of calculi, periureteral and perirenal stranding, dilatation of the collecting system, and possible alternative diagnoses and (b) cost-effectiveness: direct and indirect costs. RESULTS: Fifty-two patients had urolithiasis. The detection rate of renal and ureteric calculi was significantly higher with native spiral-CT than with IVU (100% vs. 69%, respectively) (p < 0.05). A specific sign of ureteric calculi was the so-called soft tissue "rim sign" (sensitivity 82% and specificity 100%, respectively). In 13 of 14 patients with acute flank pain with no evidence of urolithiasis alternative diagnoses could be made by spiral-CT. Spiral-CT was significantly more cost-effective than IVU in management. CONCLUSION: Native spiral-CT is faster, more effective and less expensive than IVU in the management of patients with acute flank pain. Additionally, it poses less risk and has the capability for allowing alternative diagnoses. Therefore, unenhanced spiral-CT should be the first line modality in patients with acute flank pain.

Computed tomography evaluation of adrenal masses.

Computed tomography is the first line modality in the evaluation of patients with adrenal gland masses, and has the potential to be very accurate in the localization of adrenal gland masses in patients with diseases associated with hyperfunctioning conditions of the adrenal gland. Computed tomography allows a specific diagnosis of acute adrenal haemorrhage, adrenal myelolipoma, and adrenal cysts. It is also helpful in the assessment of patients with Addison's disease, particularly the subacute form secondary to granulomatous diseases. Quantitative evaluation of adrenal masses on unenhanced or delayed-enhanced computed tomography has been shown to be highly accurate in distinguishing adrenal adenomas from non-adenomas. Attenuation of 18 HU or less on unenhanced computed tomography scans indicates adenoma with a high specificity and acceptable sensitivity. On delayed-enhanced computed tomography scans, adrenal adenomas exhibit a greater washout of contrast material than do adrenal non-adenomas. Therefore, adrenal non-adenomas have significantly higher attenuation than adenomas on delayed-enhanced computed tomography scans obtained at arbitrarily chosen times (3-60 min) after the initiation of contrast material administration.

Mucinous biliary cystadenocarcinoma containing gas bubbles secondary to duodenal invasion.

Biliary cystadenocarcinoma is a rare, usually intrahepatic neoplasm. A case is described in which an intrahepatic cystadenocarcinoma invaded the duodenum. This resulted in intratumoral gas.

Wrist arthrography after acute trauma to the distal radius: diagnostic accuracy, technique, and sources of diagnostic errors.

RATIONALE AND OBJECTIVES: The objective of this investigation was to determine the diagnostic accuracy of wrist arthrography in the detection of interosseous ligament disruptions and of triangular fibrocartilage complex (TFCC) lesions in patients after acute wrist trauma and to define the sources of diagnostic error of wrist arthrography after recent trauma. METHODS: Twenty-two patients with radial fractures after acute wrist trauma underwent arthrography and arthroscopy of the wrist. Arthrography was performed in a standardized manner by two- or three-compartment injection technique. Subsequently wrist arthroscopy was performed within the same session. Image analysis included the evaluation of interosseous carpal ligaments, the TFCC, and the osseous structures. RESULTS: In 22 patients, 11 injuries of the intrinsic ligaments and the TFCC were diagnosed by arthroscopy, of which 9 had been diagnosed correctly with arthrography before surgery. One scaphoid fracture previously missed on conventional radiographs also could be diagnosed by arthrography. CONCLUSION: Arthrography of the posttraumatic wrist is a valuable tool in the diagnostic evaluation of interosseous carpal ligaments and the TFCC.

Magnetic resonance imaging of Achilles tendon in patients with rheumatoid arthritis.

RATIONALE AND OBJECTIVES: The authors characterize the appearance of the Achilles tendon in patients with rheumatoid arthritis and differentiate this appearance from degenerative tendinopathy in patients with chronic pain of the heel using magnetic resonance (MR) imaging. METHODS: Thirty patients with rheumatoid arthritis and 28 patients with chronic pain of the heel underwent MR imaging of the ankle and foot. Three radiologists independently assessed the MR images with respect to size, shape, and intratendinal signal characteristics of the Achilles tendon. The Achilles tendon was considered abnormal on MR imaging when intratendinous signal alterations or an anteroposterior measurement greater than 8 mm was seen. Physical examination of the Achilles tendons was accomplished in both groups. Operation confirmed the diagnosis of 13 patients in the second group with chronic pain of the heel. RESULTS: The Achilles tendon of 83% of patients with rheumatoid arthritis demonstrated various intratendinous patterns (longitudinal, reticular, nodular) of intermediate signal intensity on all pulse sequences on MR imaging. Ninety percent of patients with rheumatoid tendinopathy showed no enlargement of the anteroposterior diameter of the Achilles tendon. In addition, all patients with rheumatoid arthritis had findings compatible with an inflammation of the retrocalcaneal bursa on MR imaging, whereas none of the patients with tendinopathy associated with chronic heel pain had retrocalcaneal bursitis. All patients, however, had enlargement of the anteroposterior diameter of the Achilles tendon. Seventy-nine percent showed various intratendinous lesions of intermediate signal intensity on all pulse sequences. Twenty-one percent of patients had an enlargement of the Achilles tendon without intratendinous changes. CONCLUSIONS: Rheumatoid tendinopathy can be distinguished from degenerative tendinopathy in patients with chronic pain of the heel with MR imaging. Inflammation of the retrocalcaneal bursa and the absence of enlargement of the tendon combined with the presence of intratendinous signal alterations are characteristic findings of rheumatoid tendinopathy.

Dual-energy X-ray absorptiometric densitometry in osteoarthritis of the hip. Influence of secondary bone remodeling of the femoral neck.

PURPOSE: The aim of this study was to evaluate the influence of buttressing on bone densitometry measurements in the femoral neck, in Ward's triangle, and in the greater trochanter. In addition, we attempted to establish the length of the femoral axis (FAL) and the true length of the femoral neck (FNL) as potential correlates with osteoarthritis (OA) or with buttressing. MATERIAL AND METHODS: Our study comprised 101 hips in 68 adult patients. Conventional radiographs of the hip joints were obtained in order to assess the presence and extent of OA by means of the 6-step grading system introduced in 1990 by CROFT et al., and in order to measure the cortical thickness at the medial aspect of the femoral neck. In addition, FAL and FNL were measured. All patients underwent dual energy x-ray absorptiometry so that bone density could be assessed in the femoral neck, in Ward's triangle, and in the greater trochanter. The Spearman rank correlation was used to compare the measurements. RESULTS: Statistical analysis showed a significant positive correlation between cortical thickness and bone density in the femoral neck and in Ward's triangle. No correlation was found between cortical thickness and bone density in the greater trochanter, nor between cortical thickness and OA, FNL, and FAL, nor between OA and bone density, FNL, and FAL. CONCLUSION: Buttressing influenced our bone density measurements in the femoral neck and in Ward's triangle. It did not affect the region of the greater trochanter which may therefore be the best region of interest for a long-term follow-up of bone density in patients with OA.

Measurements of cortical thickness in experimentally created endosteal bone lesions: a comparison of radiography, CT, MR imaging, and anatomic sections.

OBJECTIVE: The purpose of this study was to evaluate the accuracy of cortical measurements of experimentally created endosteal cortical lesions and to assess the sensitivity of radiography, CT, and MR imaging in the detection and measurement of such lesions. MATERIALS AND METHODS: Thirty-six cortical lesions were created in three fresh cadaveric femurs. After performing radiography, CT, and MR imaging, we sectioned the specimens in the axial plane. We then measured the remaining cortex at the lesions and the normal cortex adjacent to the lesions on all images and corresponding anatomic sections. The measurements of thickness of the cortex as seen with the different imaging methods and the anatomic sections were compared. Measurements were repeated to evaluate the influence of different window settings on the MR imaging measurements. RESULTS: When measured on radiographs, cortical thickness was overestimated in 58% of lesions. With CT, cortical thickness was overestimated by 0-15% in 94% of all lesions. With MR imaging, cortical thickness was uniformly underestimated by 3-17%. Measurements made on MR images varied according to different window settings. The proton density-weighted sequence yielded the highest sensitivity in the detection of shallow cortical lesions; the T1-weighted spin-echo sequence was the least sensitive of the MR sequences. CONCLUSION: In our cadaveric study, cortical thickness in the presence of endosteal lesions was overestimated on radiographs and CT scans and underestimated on MR images. Measurements derived from MR imaging are strongly influenced by the window setting. MR imaging with the proton density-weighted sequence is the most sensitive for detection of shallow cortical lesions and is more sensitive than CT.

Symptomatic herniation pits of the femoral neck: anatomic and clinical study.

OBJECTIVE: The purpose of this study was to investigate the pathogenesis of herniation pits of the femoral neck, which are frequently considered a normal variant, and to describe the imaging abnormalities of such pits in three symptomatic patients. CONCLUSION: The changing relationship between the joint capsule and the iliopsoas muscle appears to be important in the pathogenesis of the herniation pit, especially in athletic persons. In some cases, these pits may enlarge, the overlying cortex may fracture, and significant clinical manifestations may be apparent.