Biomedical subjects
Publications and source records attributed to A Rahmouni.
Type 1 neurofibromatosis is one of the most common autosomal-dominant disorders and often includes orthopedic manifestations. We report the case of a 48-year-old woman with hemarthrosis caused by a popliteal cyst infiltrated by a diffuse neurofibroma associated with angiodysplasia. Surgical resection of this tumor was followed by postoperative hemorrhagic complications.
Subclavian and superior vena cava obstruction complicating SAPHO (Synovitis, Acne, Pustulosis, Hyperostosis, Osteitis) syndrome has been described. We report the first case to our knowledge of iliac vein thrombosis complicating lumbar vertebral osteitis due to SAPHO syndrome. Lumbar MRI demonstrated a large tissue mass anterior to the involved vertebras and surrounding the right iliac vein. Histology of the mass showed aseptic inflammation.
PURPOSE: To compare changes in gadolinium enhancement at magnetic resonance (MR) imaging with outcome in mediastinal lymphoma after treatment. MATERIALS AND METHODS: Thirty-one patients with bulky mediastinal lymphoma (17 with Hodgkin disease, 14 with non-Hodgkin lymphoma) underwent serial MR imaging before and up to 50 months after treatment, with routine follow-up (including computed tomography). Signal intensity ratios between masses and muscle were calculated on T1-weighted, T2-weighted, and contrast material-enhanced T1-weighted spin-echo MR images. The percentage enhancement and signal intensity ratios of mediastinal masses on T2-weighted MR images were calculated at diagnosis and during and after treatment. RESULTS: Twenty-one patients with persistent complete remission had a mean percentage enhancement of residual masses (4%; range, -26% to 40%) that was significantly lower than that of initial masses (78%; range, 41%-124%). Although the mean signal intensity ratio of residual masses on T2-weighted images was significantly lower than that of initial masses, an increase in this ratio was observed in four patients after treatment. In seven patients with relapse, the percentage enhancement value of the residual mass was as high as that of the initial mass. CONCLUSION: Gadolinium enhancement of lymphomatous masses of the mediastinum decreased markedly after treatment in patients in continuous complete remission but not in patients with relapse.
Technical developments have considerably reduced the acquisition time and have improved the quality of magnetic resonance imaging. The recent recommendations of the European Society of Cardiology place MRI in the front line of investigations for the diagnosis and evaluation of congenital heart disease, cardiac tumours and pathology of the pericardium and great vessels. With the possibility of obtaining oblique planes in all 3 dimensions, MRI is the reference for the measurement of left ventricular mass, volumes, and ejection fraction, with the major advantage of not depending on hypotheses of left ventricular geometry. In addition to these known applications, the development of functional cardiac MRI has led to significant advances in the study of regional myocardial function and perfusion. The aim of this article is to discuss present indications and the potential developments of functional cardiac MRI, focusing on the quantitative evaluation of myocardial function and perfusion.
BACKGROUND & AIMS: Because most patients with focal nodular hyperplasia (FNH) are young women, an important decision is whether to discontinue oral contraceptive (OC) use. The aims of this study were to evaluate (1) the number and size of FNH lesions in women with various patterns of OC use and in women without OC use and (2) the modifications in the number and size of FNH lesions during follow-up, according to OC use. METHODS: In a 9-year study in 216 women with FNH, the diameter and number of lesions documented by magnetic resonance (MR) imaging were evaluated (1) at diagnosis according to OC use as follows: group A, no OC use (n = 28); group B, high-dose OC use (n = 46); group C, low-dose OC use (n = 98); group D, successive use of high-dose and low-dose OCs (n = 33); and group E, use of progestogens only (n = 11); and (2) during follow-up in 136 women, 14 of whom were OC nonusers who stayed off OCs, 89 discontinued OC use, 26 took low-dose OCs, and 7 stayed on a progestogen only. Twelve women became pregnant. In 168 women, the diagnosis of FNH was made based on a combination of rigorously defined MR criteria. In the remaining 48 patients, diagnosis was by surgical biopsy (n = 36) or resection (n = 12). Mean diameter and number of lesion(s) per patient were assessed by MR imaging using the same protocol in all study patients. RESULTS: No significant differences in the number or size of lesions were found in the 5 patient groups. During follow-up, a change in lesion diameter occurred in only 4 women; this event was not influenced by OC use. In the 12 patients who became pregnant, lesion size was unchanged after delivery, pregnancy was uneventful, and delivery occurred spontaneously. CONCLUSIONS: These data suggest that (1) neither the size nor the number of FNH lesions are influenced by OC use; (2) size changes during follow-up are rare and do not seem to depend on OC use; and (3) pregnancy is not associated with FNH changes or complications.
BACKGROUND: The etiologic work-up of hypertension with hyperaldosteronism and elevated serum renin includes search for renal artery stenosis. Intrinsic stenosis is a common finding, but hypertension secondary to extrinsic compression of the renal artery is exceptional. CASE REPORT: A 48-year-old woman with an uneventful history was hospitalized for recent onset hypertension. Laboratory tests showed hypokaliemia, and elevated aldosterone and renin. Duplex Doppler exploration of the renal vessels evidenced extrinsic compression of the left renal artery by a tumoral mass found to be a nodal metastasis at surgery. Pathology reported cancer of the ovary. Blood pressure, and aldosterone and renin levels returned to normal after complete tumor resection. No antihypertensive treatment was required. CONCLUSION: This is undoubtedly the first case of metastatic cancer of the ovary revealed by hypertension; it can be added to the list of 49 other published cases of extrinsic compression of the renal artery by various causes leading to hypertension. In most cases, surgical removal of the obstacle or nephrectomy provided cure of the hypertension.
With the use of available liver magnetic resonance contrast agents, such as mangafodipir (Mn-DPDP), liver metastases do not exhibit enhancement on T1-weighted images. This absence of enhancement is due to the lack of hepatocytes within these tumors. The purpose of this report is to demonstrate an unexpected enhancement on T1-weighted images 30 minutes after injection of mangafodipir, in the case of endocrine liver metastases from a non-hyperfunctioning neuroendocrine pancreatic tumor. Different hypotheses could explain this unexpected enhancement, such as increased arterial tumoral flow or high metabolic activity. Contrary to liver metastases of other origins, Mn-DPDP enhancement can be present in neuroendocrine metastases. J. Magn. Reson. Imaging 1999;10:193-195.
The aim of this work was to study the ability of mangafodipir trisodium (Mn-DPDP)-enhanced MR imaging in differentiating malignant from benign hepatocellular tumors. Eleven patients with pathologically proved hepatocellular carcinomas, six with focal nodular hyperplasias, and one with a single hepatocellular adenoma were examined by spin-echo and gradient-echo T1-weighted sequences before, 1 h after, and 24 h after intravenous injection of Mn-DPDP (5 micromol/kg). Quantitative analysis including enhancement and lesion-to-liver contrast-to-noise ratio, and qualitative analysis including the presence of a central area and a capsule were done on pre- and post-Mn-DPDP-enhanced images. Enhancement was observed in all the tumors with significant improvement (p < 0.05) in contrast-to-noise ratio 1 h after, and 24 h after intravenous injection of Mn-DPDP. There were no significant differences in the mean enhancement and the mean contrast-to-noise ratio (CNR) between benign and malignant tumors. No enhancement was seen within internal areas observed in 7 hepatocellular carcinomas, and in 5 focal nodular hyperplasias, and within capsules which were observed in 9 hepatocellular carcinomas. In our study, Mn-DPDP increased CNR of both benign and malignant tumors but did not enable differentiation between benign and malignant tumors of hepatocellular nature.
Early diagnosis of osteomyelitis is helpful for a successful conservative treatment. The value of bone scanning combined with granulocytes labeled with hexamethylpropylene amine oxime (HMPAO) granulocyte-Tc99m (GN) radionuclide imaging (combined [RI]) with magnetic resonance imaging (MRI) for the diagnosis of osteomyelitis was assessed in 24 diabetic patients with foot ulcers. Evidence of osteomyelitis was based on the presence of at least one of the following criteria: (1) clinical bone involvement, (2) radiological bone involvement, (3) both positive combined RI and MRI, and (4) evidence of clinical bone involvement during the follow-up period. Thirteen patients had osteomyelitis. Seven patients had clinical bone involvement (sensitivity, 54%), five had radiological bone involvement (sensitivity, 38%), and 10 had positive combined RI for osteomyelitis (sensitivity, 77%). MRI demonstrated a higher sensitivity (100%). The specificity for combined RI and MRI was 82%. These results lead to a new diagnostic strategy for the early detection of minimal or localized osteomyelitis to avoid amputations. MRI is most appropriate following a negative x-ray in determining whether to treat osteomyelitis, since a negative MRI result rules out osteomyelitis. Antibiotic therapy should be used in the case of a positive MRI result, but Charcot joint disease can lead to false-positive MRI results. In this case, combined RI should be performed.
OBJECTIVE: This pictorial review analyzes the magnetic resonance (MR) fascial/muscular changes in 69 patients referred as emergencies with acute swelling of the limbs (ASL) from various causes. METHODS AND MATERIAL: A prospective MR imaging (MRI) study of 69 patients referred as emergencies for ASL was performed. Our population consisted of 45 patients with skin and soft-tissue infections (cellulitis and necrotizing fasciitis, and pyomyositis), six patients with soft-tissue inflammatory diseases (dermatomyositis, graft-versus-host disease), 11 patients with acute deep venous thrombosis, three patients with rhabdomyolysis, one patient with acute denervation and three other patients with rare diseases. Hematomas, tumorous or infectious bone involvement and soft-tissue tumors were excluded. All studies included spin echo T1-weighted images and spin echo T2-weighted images. Gadolinium-enhanced spin echo T1-weighted images were obtained when an abscess was suspected on T2-weighted images. Selective fat-saturated T1- and T2-weighted sequences were also used. MRI analysis was performed to obtain a compartmentalized anatomical approach according to the location of signal abnormalities in subcutaneous fat, superficial and deep fascia and muscle. RESULTS: In all patients with ASL, MRI demonstrated soft-tissue abnormalities involving subcutaneous fat, superficial fascia, deep fascia, or muscle. Although MR findings were non-specific, MRI appears sensitive for detecting subtle fascial and muscle signal changes. CONCLUSIONS: In skin and soft-tissue infections, MRI can be helpful for therapeutic management by determining the depth of soft-tissue involvement, particularly within fasciae and muscles, which is partly related to the severity of cellulitis with severe systemic manifestations. MRI can also aid the surgeon in diagnosing abscesses. In inflammatory diseases, MRI can determine the best site for biopsy and also monitor therapeutic response.
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The suspensory system of the penis acquires clinical importance in reparative surgery, traumatology and through its role in erection. The aim of this study was to identify the different anatomic structures constituting the suspensory ligament by dissection and by magnetic resonance imaging (MRI). Ten unembalmed male subjects were used for dissection of the region of the base of the penis. Ten volunteer patients underwent MRI of the penis before and after the injection of prostaglandin (PGE1). The suspensory apparatus consisted of separate ligamentous structures: the fundiform ligament, which is lateral, superficial and not adherent to the tunica albuginea of the corpora cavernosa; the suspensory ligament properly so-called, further back, stretching between the pubis and the tunica albuginea of the corpora cavernosa and consisting of two lateral, circumferential, and one median bundles, which circumscribed the dorsal vein of the penis. These structures were identifiable in MRI and their supporting role was evidenced during tests of erection. The suspensory ligament seemed to maintain the base of the penis in front of the pubis and to behave as a major point of support for the mobile portion of the penis during erection.
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OBJECTIVE: To study the characteristics of radiographs in diagnosis of hydroxyapatite deposits in sites other than the shoulders and hips. METHODS: We reviewed the records of patients hospitalized during the last 3 years whose final diagnosis was apatite deposits in sites other than the shoulders and hips. RESULTS: Ten women and 5 men were studied. The initial presentation mimicked septic arthritis or periarticular soft tissue abscess in 12 patients, corresponding to calcifications in the fingers (6), toes (2), wrists (2), elbow (1), and ankle (1). One patient presented with a spontaneous coccygeal pain (precoccygeal deposit), one with a pseudotumoral process of the thigh (paradiaphyseal calcification), and one with acute cervical pain and dysphagia (longus coli muscle calcification). Complete clinical healing was observed after an average of 4.9 days; 11 patients used nonsteroidal antiinflammatory drugs (NSAID), 2 used colchicine, one used oral steroids, and one had brief antibiotic therapy and used NSAID. CONCLUSION: Initial clinical aspects of apatite deposits in sites other than the shoulders and hips can often be misleading, especially by mimicking an infectious process. Careful analysis of immediate radiographic films can help to rapidly ascertain the diagnosis and thus avoid useless investigations or treatment.
PURPOSE: To describe calcification in focal nodular hyperplasia (FNH) of the liver, which poses a new problem for the differentiation of FNH from fibrolamellar hepatocellular carcinoma (HCC). MATERIALS AND METHODS: Ultrasound, computed tomography, and magnetic resonance imaging findings of 357 FNH lesions diagnosed in the past 5 years in 295 patients (274 female, 21 male; aged 14-72 years) were retrospectively reviewed with emphasis on intralesional calcification. RESULTS: Calcifications were seen in five FNH lesions (1.4%) as small, solitary spots located centrally or peripherally within the lesions. Morphologic features of these calcifications were similar to those of calcifications in two of six fibrolamellar HCCs in the same period. CONCLUSION: Calcification in FNH is a rare and atypical finding that poses further difficulty for differentiation from fibrolamellar HCC.