[Gallbladder duplication. Apropos of a case of echographic finding]. / Duplication vésiculaire. A propos d'un cas de découverte échographique.

Duplication of the gallbladder is a rare congenital anomaly, which must be depicted by sonography, although false positive and negative diagnosis could still be made. Usually abdominal sonography allows duplication diagnosis as reported in our case and a cholecystography may be performed to determine the type of the anomaly. When a surgical procedure needs to be performed, especially in case of coelioscopic technique, surgeon needs to know the exact anatomic type of the anomaly and the number of gallbladders he will find.

[Vagal paraganglioma associated with a rare malformation of the aortic arch. Apropos of a case and review of the literature]. / Paragangliome du vague associé à une malformation rare de la crosse aortique. A propos d'un cas et revue de la littérature.

The authors report about a very peculiar case of cervical paraganglioma which had two specific features. This is a familial case with 2 sisters presenting with bilateral paragangliomas. In addition, this patient's aortic trunk is very peculiar, with a retroesophageal right subclavian artery and, above all, a divided intrathoracic right common carotid artery, producing an ascending pharyngeal supply for the right paraganglioma, which can be embolized without any risks of reflux.

[Aneurysmal cyst of uncommon site. Apropos of a case. Contribution of MRI]. / Kyste anévrysmal de topographie inhabituelle. A propos d'un cas. Apport de I'IRM.

An aneurysmal bone cyst of fourth metacarpal which occurred in a 7-year-old girl was explored by MRI. MRI findings such as fluid-fluid levels were compared to literature. These levels are inconstant and not pathognomonic of aneurysmal bone cyst. They could occur within others bone tumors. Even if fluid-fluid levels are highly suggestive of aneurysmal bone cyst only pathological study asserts the diagnosis. MRI procedure might be a good procedure for post surgery follow up.

[A rare pulmonary tumor: pneumoblastoma. Apropos of a case and review of the literature]. / Une tumeur pulmonaire rare: le pneumoblastome. A propos d'un cas et revue de la littérature.

A case of pneumoblastoma concerning a 33 year old man, incidentally discovered on a systematic chest X Ray, is reported. The radiologic findings include a voluminous and peripherical mass with necrotic zones. The pathologic findings in optic microscopy and the special technics consist in the three cellular contingents which form the pneumoblastoma: clusters of indifferentiated cells, epithelial cells and spindle cells. All the features show clearly a blastomatic character very similar to a foetal lung which allows to differentiate the pulmonary blastoma from carcinosarcoma. The authors, through a review of the literature, demonstrate the rarity (less than 100 cases reported), the malignant evolution which metastasis and the age (strong majority of adults) which characterize this pathology.

[Magnetic resonance angiography of stents]. / Stents et angiographie par résonance magnétique.

PURPOSE: To understand the behavior of stents during contrast-enhanced magnetic resonance angiography (MRA). MATERIALS AND METHODS: Seven different types of stents are explored in vitro with spin echo (SE) T2 sequence and MRA sequences using classification of the intra-prothesis signal. Six patients with 11 different proximal stents are studied by Gadolinium enhanced MRA with the same classification. RESULTS: Stent material is not the only determinant of behavior. In this way, one stainless steel stent produced less intra-luminal hyposignal than a nitinol device. Nevertheless, only a nitinol stent did not alter the intra-prothesis signal and allowed an appreciation of patency, despite a decrease of diameter and presence of edge artifacts. CONCLUSION: Even if stent compatibility is well known with MRI, even with Gadolinium, cannot be used alone to depict stenosis or diameter reduction. Even patency based on the presence of a constant signal, cannot be confirmed routinely with confidence: indeed, only a single stent does not modify intra-arterial signal.

[Study of atheromatous stenoses of carotid bifurcations by Doppler ultrasound, spiral angio-MRI, magnetic resonance angiography and comparison with arteriography]. / Etude des sténoses athéromateuses des bifurcations carotidiennes par écho-Doppler, angioscanner spiralé, angio-IRM et comparaison à l'artériographie.

PURPOSE: To evaluate Doppler ultrasound (US), Helical CT, Magnetic Resonance (MR) angiography in the detection of carotid bifurcation atherosclerotic disease and comparison with angiography. MATERIALS AND METHODS: After a Doppler US procedure, 56 carotid bifurcations were included (symptomatic stenosis greater than 60% or asymptomatic stenosis greater than 30%). Helical CT, MR angiography and selective arteriography were performed. Stenosis were measured with NASCET criteria. Sensitivity and specificity were calculated and compared to arteriographics findings for each procedure and each grade of stenosis. RESULTS: Helical CT and MR angiography had their best sensitivity in grade 3 (70-99%), 92%, 100% respectively, their specificity was identical (91%). All the occlusions were depicted by the three procedures. CONCLUSION: Association of Doppler US and MR angiography may replace in the future selective angiography in the evaluation of extracranial atherosclerotic disease. Arteriography would be performed only in case of discordance between these two procedures.

[Tracheo-bronchopathia chondro-osteoplastica. X-ray computed tomographic signs]. / La trachéo-bronchopathie chondro-ostéoplastique. Signes tomodensitométriques. A propos d'une observation et revue de la littérature.

The authors report a case-report of tracheo-bronchopathia chondro-osteoplastica with High-Resolution CT scan examination. They emphasize the rarity of this disease, its long clinical latency and the radiologic patterns of tracheal stenosis and calcificated in ward projecting formations from the tracheal wall. The radiologic diagnosis is discussed. Endoscopy and histology are the diagnosis. The etiology, prognosis and specific treatment remain unknown.

[Pulmonary hemangiopericytoma. Apropos of a case and review of the literature]. / Hémangiopéricytome pulmonaire. A propos d'un cas et revue de la littérature.

Hemangiopericytoma is a rare vascular tumor of pericyte origin and of variable but always preoccupying potential since falling within the category of sarcomas. A thoracic localization is rare and primary pulmonary parenchyma lesions even more so, only 87 cases being reported in the literature. Radiological diagnostic criteria are of weak specificity, diagnosis being provided by thin section CT scan imaging with contrast. The differential diagnosis of these vascular tumors includes arteriovenous fistula, pulmonary varices, other vascular tumors or even organized bronchomucoceles. The value of CT scan puncture is obviously limited. The course is unpredictable since even histopathology findings fail to provide definitive data.

[Peritoneal mesothelioma. Contribution of MRI. Apropos of a case]. / Mésothéliome péritonéal. Apport de I'IRM. A propos d'un cas.

Peritoneal invasion by a malignant mesothelioma is less frequently encountered than pleural localization. We report a case of a double pleural and peritoneal localization. CT and MR may be suggestive, especially when pulmonary asbestosis is associated, but pathology (fine needle aspiration or surgical biopsy) is necessary to assess the diagnosis. When possible surgery is performed, with or without associated radiotherapy. Prognosis is nevertheless very poor.

[MRI/CT x-ray comparison in the pre-operative evaluation of cancer of the larynx. Apropos of 46 cases]. / Comparaison IRM/TDM dans le bilan pré-opératoire des cancers du larynx. A propos de 46 cas.

The authors present the comparative value of CT scan and MRI in the pre-operative staging of 46 laryngeal carcinomas. The "in depth" evaluation conducts the choice of conservative surgery. CT scan is the reference but MRI reveals itself as effective and even more in certain cases. The spontaneous contrast gradient for soft tissues of the MR imaging explains this effectiveness of the method. The paraglottic space and the subglottic extension are more easily studied by MRI. If the expansion of the MRI Unities allows this indication of the pre-operative staging of laryngeal carcinomas is an excellent one.

[Pulmonary alveolar proteinosis. Apropos of a case. The value of mm.-thick CAT scan sections. A pulmonary lobe anatomic approach]. / Protéinose alvéolaire pulmonaire. A propos d'un cas. Apport des coupes millimétriques TDM. Approche de l'anatomie lobulaire pulmonaire.

Is by its acinar-shadows and interstitial enhancement a pathologic situation of optimal value for the study of alveolar and lobular anatomy. Millimetric slices with high resolution C.T. Scanning seem to be Gough anatomic preparations and are very favourable for the inner anatomy pulmonary study.

[Thoracic extramedullary hematopoiesis. Apropos of a case]. / Hématopoïèse extra-médullaire thoracique. A propos d'une observation.

Extramedullary haematopoiesis is a compensatory response of bone marrow to abnormal haematopoietic tissue formation: the commonest etiology is thalassemia (generally intermedia). The thorax is a rare site and the posterior mediastinum is usually involved. CT scan completes standard chest radiology and allows fine needle aspiration to provide adequate cytologic material for the diagnosis of extramedullary haematopoiesis, especially when an intercurrent pathology is present and could involve paravertebral areas. Thoracotomy may be necessary in rare cases of complications.

[Intrarenal migration of two fractured struts of a vena cava filter]. / Migration intra-rénale de deux branches fracturées d'un filtre cave.

Filter complications are quite common. The most frequent are distal or proximal migration, angulation, vena cava thrombosis or perforation. We report one case of filter struts fracture and their migration in the right kidney. This complication could require a surgical procedure and demonstrates the importance of filter follow-up with regular abdominal plain X-rays and possibly CT scan and/or cavography.

Pre-therapeutic evaluation of laryngeal carcinomas using computed tomography and magnetic resonance imaging.

A prospective and comparative computed tomography (CT)/magnetic resonance imaging (MRI) study on 90 patients with endoscopically examined and histologically proven laryngeal malignancy is presented. Post-operative pathological and intra-radiological (CT vs. MRI) correlations are established. We conclude that MRI is the method of choice for staging laryngeal malignancies.

[Malignant adrenocortical carcinoma with atypical aspect. Value of tomodensitometry and magnetic resonance imaging. Apropos of a case]. / Corticosurrénalome malin de présentation atypique. Intérêt du scanner et de l'IRM. A propos d'un cas.

A case of large and non-functioning malignant adrenal tumor is reported. It was discovered incidentally during a check-up ordered because of sciatic pain caused by an osteolytic lesion of the sacrum. This huge abdominal tumor was suspected to be an adrenal tumor one the basis of the CT and MR findings. Histological analysis of percutaneous biopsies were unable to define the site and etiology of these two masses. Only histo-pathological examination of the surgical specimen allowed the diagnosis of adrenal cortical carcinoma.

Experimental demonstration of a phased-array antenna optically controlled with phase and time delays.

The experimental demonstration and the far-field pattern characterization of an optically controlled phased-array antenna are described. It operates between 2.5 and 3.5 GHz and is made of 16 radiating elements. The optical control uses a two-dimensional architecture based on free-space propagation and on polarization switching by N spatial light modulators of p × p pixels. It provides 2(N-1) time-delay values and an analog control of the 0 to 2π phase for each of the p × p signals feeding the antenna (N = 5, p = 4).

[Spontaneous rupture of the rectum. Contribution of CT scan. Apropos of a case]. / Rupture spontanée du rectum. Apport du scanner. A propos d'un cas.

We report a case of spontaneous rupture of the rectosigmoid junction demonstrated by surgical and histological examination. This rare complication of chronic constipation is difficult to confirm except in the case of the typical clinical presentation with lower abdominal pain after defaecation and evisceration of small intestine loops through the anus. No radiological procedure is usually performed except for plain abdominal radiograph, to demonstrate inconstant (retro)peritoneal emphysema. CT scan could detect free air outside of the rectosigmoid lumen, suggesting parietal rupture and allowing appropriate surgical treatment on the lower digestive tract.

[Magnetic resonance imaging of the larynx. Its contribution compared to x-ray computed tomography in the pre-therapeutic evaluation of cancers of the larynx. Apropos of 90 surgical cases]. / L'imagerie par résonance magnétique du larynx. Apport comparé à celui de la tomodensitométrie dans le bilan pré-thérapeutique des cancers du larynx. A propos de quatre-vingt dix cas opérés.

The authors report a prospective and comparative study of the pre-operative staging of 90 laryngeal carcinomas by CT and MRI, with blind analysis of each examination. The radio-anatomic correlations and the inter-method correlations (CT versus MRI) are reported. According to the authors MRI seems to be the method of choice because of its capabilities in soft tissues differentiation and because of its multiplanar representation. The motion artefacts are resolved by the fast imaging technique and the spatial resolution is optimized by special surface coils.