[Muculoskeletal radiology: ankle and foot in adults]. / Radiologie osseuse: cheville et pied de l'adulte.

The main views and indications in adult foot and ankle radiography are detailed. Among foot and ankle diseases, mechanical ones are most frequent, including usual podologic changes (commonly followed by peculiar involvement of certain bones, ligaments, joints, tendons and other soft tissues), synostoses, occult and stress fractures, sprains, and tendon changes. Although they are less frequently encountered in common clinical practice, the radiographic appearance of inflammatory, infectious, and tumoral diseases of foot and ankle are disclosed as well. The correlation existing between some subtle radiographic changes and their counterpart on US, CT, or MR examinations are also emphasized.

Gluteal tendinopathy in refractory greater trochanter pain syndrome: diagnostic value of two clinical tests.

OBJECTIVE: To evaluate the value (sensitivity and specificity) of 2 modified physical tests for the diagnosis of gluteal tendinopathy in patients with refractory greater trochanter pain syndrome (GTPS). METHODS: The 2 tests were prospectively evaluated by a single physician in all consecutive patients with persistent (> or =4 months) GTPS and no hip joint arthropathy seen on radiography between 2002 and 2006. The 2 tests evaluated the occurrence of pain similar to spontaneous pain during a single-leg stance held for 30 seconds and resisted external derotation in a supine position (hip flexed 90 degrees ) then prone position (hip extended). A matched control population without hip pain was examined similarly. Tendinitis, tendon tear, and associated bursitis in the target group were documented by magnetic resonance imaging (MRI) in transverse, coronal, and sagittal planes, with MRI serving as the gold standard. RESULTS: Seventeen patients completed the study (mean +/- SD age 68.1 +/- 10.8 years, mean duration of symptoms 13 months). MRI revealed tendinopathy and/or bursitis of the gluteus medius and/or minimus tendons in all patients, with evidence of tearing in 15. Sensitivity and specificity were 100% and 97.3%, respectively, for the single-leg stance test and 88% and 97.3%, respectively, for the resisted external derotation test in the supine position. CONCLUSION: The 30-second single-leg stance and resisted external derotation tests had very good sensitivity and specificity for the diagnosis of tendinous lesion and bursitis in patients with MRI-documented refractory GTPS.

[The "de Sèze" magnetic imaging]. / Le "de Sèze" magnétique.

The authors propose that a coronal STIR sequence with large FOV, similar to the de Sèze projection, including lumbar spine, sacrum, pelvis and hips should be obtained in all patients as part of the lumbar spine MRI protocol. For an additional few minutes of scanning time, this additional sequence could demonstrate the presence of lesions (hips, pelvis, sacrum, SI joints, retroperitoneum...) that would otherwise go undetected on standard sagittal and axial MRI images of the lumbar spine.

[Normal and abnormal imaging of the foot's extensor system]. / Imagerie normale et pathologique du système suro-achilléo-plantaire propulseur du pied.

The extensor system of the foot is mainly composed by a powerful engine, the triceps surae muscle, equiped with a very sophisticated driving belt, the unit Achilles tendon-posterior part of calcaneus bone-plantar aponeurosis, in continuity with the fibrous skeleton of the triceps surae. The exact knowledge of the anatomy of this fibrous skeleton allows us to understand the occurence of the main anatomical lesions of the extensor system and its imaging. On these solid bases, it's possible to divide the lesions of the foot's extensor system in different subtypes with, for each one, a typical clinical feature, a characteristic imaging and an codified treatment. The pair radiography-ultrasonography is enough for diagnosis and follow-up of the majority of lesions. The others need MRI.

Crowned dens syndrome misdiagnosed as polymyalgia rheumatica, giant cell arteritis, meningitis or spondylitis: an analysis of eight cases.

BACKGROUND: The crowned dens syndrome, related to microcrystalline deposition in the peri-odontoid articular and abarticular structures, is mainly responsible for acute or chronic cervical pain. PATIENTS: We report eight cases of crowned dens syndrome with atypical presentations mimicking giant cell arteritis, polymyalgia rheumatica, meningitis or discitis. The clinical and radiological aspects of these cases are presented and discussed. RESULTS: For all patients, fever, cervical stiffness, headaches and biological inflammatory syndrome were reported. For three patients, impairment of general condition, occipito-temporal or mandible pain and weakness with inflammatory pain of the shoulder girdle was suggestive of giant cell arteritis and/or polymyalgia rheumatica, leading to temporal artery biopsy and/or long-term steroid treatment. Recurrence of clinical symptoms when tapering steroids was noted. In two cases, previous breast carcinoma led to the initial diagnosis of metastatic spondylitis. For three patients with vomiting, nausea and Kernig's and/or Brudzinski's sign, the first diagnosis was meningitis, leading to unhelpful lumbar puncture. In all cases, diagnosis of crowned dens syndrome once evoked, was confirmed by cervical CT scanning and dramatic improvement with non-steroidal anti-inflammatory drugs or colchicine. CONCLUSION: This under-recognized entity must be considered as a differential diagnosis of meningitis and discitis, but also of giant cell arteritis and polymyalgia rheumatica, as well as a possible aetiology for fevers of unknown origin. CT scanning is necessary for diagnosis. Clinicians should be aware of such misleading clinical presentations.

Vertebral tumors and pseudotumors.

This article discusses lesions that may present as vertebral tumors at radiologic examination. Conditions are discussed in order of decreasing frequency: pseudotumoral lesions, vertebral metastases, bone marrow diseases, and primary vertebral tumors, which are relatively uncommon. The differential diagnosis between nontraumatic benign and malignant vertebral collapses is also discussed.

Multifocal osteogenic sarcoma in Paget's disease.

The most serious complication of Paget's disease is sarcomatous degeneration of pagetic bone. Multifocal sarcomatous degeneration occurs mainly in polyostotic Paget's disease. Multifocal Paget's sarcoma is uncommon and can arise in any site. We report two cases of synchronous multifocal sarcomatous degeneration. The two patients were elderly women (aged 77 and 86 years, respectively) who developed sarcomatous lesions concomitantly, in the first case report in left ilium, left tibia, and first lumbar vertebra and in the second case report in the skull, right ilium, and sacrum. Whether these cases are due to the simultaneous development of several primaries or to metastases from a single primary remains unclear.

Mechanisms of action of liver contrast agents: impact for clinical use.

New contrast agents for magnetic resonance imaging are continually being developed by pharmaceutical companies in order to better image the liver. These agents can be divided into hepatobiliary agents directed to the hepatocytes and nanoparticulate agents directed to the reticulo-endothelial system. After intravenous injection, all these agents concentrate in the liver and induce profound changes in signal intensity. Particulate agents induce predominantly a darkening of the liver parenchyma, while hepatobiliary agents induce a brightening. In both cases, liver-lesion conspicuity is enhanced, leading to a better visualization of the lesion. After a brief description of the principal characteristics of the agents, this paper will attempt to summarize the utility of these agents for the detection and characterization of focal liver disease.

Measurement of liver blood volume using a macromolecular MRI contrast agent at equilibrium.

Liver regional blood volume (LRBV) is altered by several disease states and various drugs. Preliminary studies in the rat, using research MR imaging instruments at 2T and vascular contrast agents, have suggested that MRI may be used to measure LRBV. Our goal was to develop a technique for measuring LRBV using a clinical machine at 1.5 T. This study was performed in the rabbit, using CarboxyMethylDextran Gd-DTPA, a macromolecular contrast agent with a molecular weight of 158 kDa. MRI was performed at 1.5 T, in the plane of the inferior vena cava, with and without flow compensation, before contrast injection and in the steady state after injection. Accuracy and stability of LRBV measurement, over 2 h and with various doses (0.01-0.05 mmol/kg), was tested against a standard Evan's Blue dye-indicator technique. LRBV was 28 +/- 2 mL/100 g when measured by MRI with flow compensation, which is in good agreement with the literature and with the 26 +/- 6 mL/100 g, measured by the Evan's Blue dilution technique. Measurements varied less than 7% over time and less than 9% over the range of doses. LRBV was overestimated using a sequence without flow compensation especially when large doses of contrast agent were injected. This noninvasive MRI technique provides a simple method for measuring liver LRBV and offers new prospects for future physiological and pathological studies.

[Imaging of atypical cysts of the liver. Study of 26 surgically treated cases]. / Imagerie des kystes atypiques du foie. Etude de 26 lésions opérées.

OBJECTIVES: Differential diagnosis between a benign cystic hepatic lesion, biliary cyst, and a potentially malignant lesion or biliary cystadenoma, is difficult. The aim of this study was to evaluate imaging features of atypical cystic liver lesions and the role of imaging techniques in determining a specific diagnosis. METHODS: Twenty-six patients with atypical cystic hepatic lesions were included in this study. All patients underwent surgery and pathological diagnosis was atypical hepatic cyst (n = 18), biliary cystadenoma (n = 4), hydatic cyst (n = 3), and ciliated hepatic foregut cyst (n = 1). We systematically reviewed US (n = 24), CT (n = 24), and MRI (n = 8) examinations. RESULTS: Septum were seen in both cystadenomas (US: n = 4, CT: n = 1) and hepatic cysts (US: n = 11, CT: n = 6). No mural nodules were seen. A thin wall was noted in both hepatic cysts (n = 2) and cystadenomas (n = 3). The intrahepatic biliary tract was dilated in 3 patients with hepatic cysts, 1 patient with cystadenoma, and 2 patients with hydatic cysts. Calcifications were noted in 1 patient with hepatic cyst, 3 patients with hydatic cysts, and in the case of ciliated hepatic foregut cyst. We found an associated typical hepatic cyst in 77% of cases (14/18) with atypical hepatic cysts; this was never found in other atypical cystic lesions (P < 0.01). CONCLUSION: In this series, no imaging features provided a differential diagnosis of atypical hepatic cysts and cystadenomas. The presence of associated typical hepatic cysts is helpful in suggesting the diagnosis of hepatic cyst.