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Dive into the research topics where Robert Sigal is active.

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Featured researches published by Robert Sigal.


Abdominal Imaging | 2008

Staging of peritoneal carcinomatosis: enhanced CT vs. PET/CT.

Clarisse Dromain; Sophie Leboulleux; Anne Auperin; Diane Goéré; David Malka; Jean Lumbroso; Martin Schumberger; Robert Sigal; Dominique Elias

PurposeTo assess and compare the performance of CT and 18F-FDG-PET/CT in the evaluation of peritoneal carcinomatosis (PC).Method and materialsThirty consecutive patients with PC and scheduled for a surgery underwent a CT of the abdomen and pelvis and a whole-body 18F-FDG PET/CT. The extent of PC was assessed precisely using the peritoneal cancer index combining the distribution of tumor throughout 11 abdominopelvic regions with a lesion size score. CT and PET/CT imaging results were compared in all patients with intraoperative findings using an interclass correlation test.ResultsThe presence of PC was correctly determined on CT and PET/CT in 23/28 and 16/28 patients, respectively. The extent of PC was understaged with CT and PET/CT in 27 patients and overstaged with CT and PET/CT in 1 and 2 patients, respectively. The interclass correlation was 0.53 (moderate) between CT and surgery and 0.12 (low) between PET/CT and surgery. The interclass correlation was higher for mucinous tumor (0.63) than for non-mucinous (0.16) on CT imaging whereas no difference was found in PET/CT.ConclusionThe intraperitoneal assessment of the extent of carcinomatosis, necessary to assess prognosis and treatment planning, is not accurate enough with CT and PET/CT imaging.


American Journal of Roentgenology | 2006

Evaluation of Tumor Angiogenesis of Breast Carcinoma Using Contrast-Enhanced Digital Mammography

Clarisse Dromain; C. Balleyguier; Serge Muller; Marie-Christine Mathieu; Paule Opolon; Robert Sigal

OBJECTIVE The purpose of this article is to assess the accuracy of contrast-enhanced digital mammography in the detection of breast carcinoma and to correlate the findings on the images with those of histologic analysis using microvessel quantification. SUBJECTS AND METHODS Twenty patients with a suspicious breast abnormality underwent contrast-enhanced digital mammography using a full-field digital mammography unit that was modified to detect iodinated enhancement. For each patient, a total of six contrast-enhanced craniocaudal views were acquired from 30 seconds to 7 minutes after the injection of a bolus of 100 mL of an iodinated contrast agent. Image processing included a logarithmic subtraction and the analysis of enhancement kinetic curves. Contrast-enhanced digital mammography findings were compared with histologic analysis of surgical specimens, including intratumoral microvessel density quantification evaluated on CD34-immunostained histologic sections obtained from all patients. RESULTS An area of enhancement was depicted on contrast-enhanced digital mammograms in 16 of the 20 histologically proven breast carcinomas. Excellent correlation was seen between the size of enhancement and the histologic size of tumors, which ranged from 9 to 22 mm. Early enhancement with washout was observed in four cases, early enhancement followed by a plateau in four cases, gradual enhancement in seven cases, and unexpected decrease of enhancement in one case. Intratumoral microvessel density ranged from 11.7 to 216.6 microvessels per square millimeter. A poor correlation was found between data measured on contrast-enhanced digital mammography and intratumoral microvessel density measured on CD34-immunostained histologic sections. CONCLUSION Contrast-enhanced digital mammography is able to depict angiogenesis in breast carcinoma. Breast compression and projective images acquisition alter the quantitative assessment of enhancement parameters.


Dysphagia | 2003

Morphologic parameters of normal swallowing events using single-shot fast spin echo dynamic MRI.

Dana M. Hartl; Marcella Albiter; Frédéric Kolb; B. Luboinski; Robert Sigal

This study was designed to determine visible and measurable morphological parameters in normal swallowing using dynamic MRI with single-shot fast spin echo (SSFSE), as a preliminary study in view of noninvasive MRI swallowing evaluation in patients with dysphagia. Seven healthy volunteers aged 24–40 underwent dynamic MRI with SSFSE, with a 1.5-T unit, using a head and neck antenna. Patients repeated dry swallow, water swallow, marshmallow swallow, cake swallow, and cookie chewing for a total of five series, with 15 acquisitions per series at a rate of 700 ms per acquisition. A checklist of swallowing events and anatomic landmarks was used to determine which anatomic landmarks are always visible, which phases or swallowing movements are always visible, and which landmarks can be used to measure oral and pharyngeal motion in swallowing. The oral preparatory, oral, and oropharyngeal phases of deglutition were visible in all cases. No aspiration, reflux, or abnormal residue was observed. Spatial resolution allowed for anatomical measurements of laryngeal elevation, oropharyngeal diameter, and tongue base and velum displacement in all cases. SSFSE dynamic MRI is pertinent for evaluation of the anatomical and physiological characteristics of swallow. The temporal parameters, however, cannot be studied using this technique. Motion artifacts preclude its use in the study of mastication. It remains complementary to videofluoroscopy and other techniques in swallow evaluation.


Dysphagia | 2006

Cine Magnetic Resonance Imaging with Single-Shot Fast Spin Echo for Evaluation of Dysphagia and Aspiration

Dana M. Hartl; Frédéric Kolb; Evelyne Bretagne; P. Marandas; Robert Sigal

The aim of this study was to determine the feasibility of and interest in evaluation of swallowing using dynamic magnetic resonance imaging (cine-MRI) in patients with dysphagia and aspiration caused by an abnormal pharyngeal phase of swallow. A cohort of six patients previously treated for head and neck cancer with persistent dysphagia and/or aspiration were evaluated an average of 47 months after treatment. The morphology and mobility of the oral, oropharyngeal, and laryngeal structures were analyzed using cine-MRI using single-shot fast spin echo technology. The qualitative observations were compared with a clinical fiberoptic swallowing evaluation. Swallowing physiology was analyzable for dry (saliva) swallow in all patients. MRI was well-tolerated by all six patients and no clinical aspiration occurred during the MRI. In five of six cases, further information on the cause of dysphagia was obtained using cine-MRI compared with the clinical evaluation alone. In the remaining case, cine-MRI confirmed the clinical evaluation. Cine-MRI using the dry swallow technique is feasible and without risk in patients with clinical aspiration. Cine-MRI is complementary to clinical evaluation of swallowing in patients with an abnormal pharyngeal phase of swallowing resulting from treatment of cancer.


European Journal of Radiology | 2009

Dynamic optical breast imaging : A novel technique to detect and characterize tumor vessels

L. Fournier; Daniel Vanel; A. Athanasiou; Wolfgang Gatzemeier; I.V. Masuykov; Anwar R. Padhani; Clarisse Dromain; Ken Galetti; Robert Sigal; Alberto Costa; Corinne Balleyguier

PURPOSE To prospectively determine the diagnostic accuracy of optical absorption imaging in patients with Breast Imaging Reporting and Data System (BI-RADS) 3-5 breast lesions. MATERIALS AND METHODS Forty-six patients with BI-RADS classification 3 (11%), 4 (44%) or 5 (44%) lesions, underwent a novel optical imaging examination using red light to illuminate the breast. Pressure was applied on the breast, and time-dependent curves of light absorption were recorded. Curves that consistently increased or decreased over time were classified as suspicious for malignancy. All patients underwent a core or surgical biopsy. RESULTS Optical mammography showed a statistical difference in numbers of suspect pixels between benign (N=12) and malignant (N=35) lesions (respectively 1325 vs. 3170, P=0.002). In this population, optical imaging had a sensitivity of 74%, specificity of 92%, and diagnostic accuracy of 79%. The optical signal did not vary according to any other parameter including breast size or density, age, hormonal status or histological type of lesions. CONCLUSION Optical imaging is a low-cost, non-invasive technique, yielding physiological information dependent on breast blood volume and oxygenation. It appears to have a good potential for discriminating benign from malignant lesions. Further studies are warranted to define its potential role in breast cancer imaging.


Skeletal Radiology | 1993

Aggressive fibrous dysplasia of the maxillary sinus.

Lorraine G. Shapeero; Daniel Vanel; Lauren V. Ackerman; Marie-Josée Terrier-Lacombe; Dominique Housin; G. Schwaab; Robert Sigal; Masselot J

Fibrous dysplasia is usually a slowly progressive, benign disease that develops over several years and presents with deformity or mild symptomatology. Five of 34 patients (ages 4–21 years), who were subsequently diagnosed histologically as having fibrous dysplasia of the maxillary sinus, rapidly developed soft tissue masses of the malar region over a period of less than 4 months with accompanying pain (2 patients) and nasal obstruction and exophthalmos (2 patients). Each was clinically suspected of having a sarcoma; two had been thought to have an “osteofibrosarcoma” on initial biopsy at outside hospitals. After resection, all lesions developed regrowth. At histopathologic examination, both initial and recurrent masses proved to be typical fibrous dysplasia with spicules of woven bone in cellular, sometimes vascular, fibrous tissue. No malignant degeneration was found.On conventional radiography, aggressive fibrous dysplasia produced opacification and expansion of the maxillary sinus and apparent disruption of its wall with an associated soft tissue mass. Computed tomography (CT) demonstrated voluminous heterogeneous masses with “ground glass appearance”, calcifications, areas of enhancement, low attenuation, cystic areas, and a thinned, sometimes interrupted, maxillary wall. Despite the aggressive clinical course for both initial and recurrent lesions, the CT findings of a “ground glass” mass with calcifications surrounded by a maxillary sinus wall, even if incomplete, can suggest the diagnosis of aggressive fibrous dysplasia.


Journal of Computer Assisted Tomography | 1992

Aneurysmal Bone Cysts of the Jaws: CT and MR Findings

Marie Pierre Revel; Daniel Vanel; Robert Sigal; B. Luboinski; Guy Michel; Isabelle Legrand; Masselot J

Two cases of aneurysmal bone cyst of the jaws, one in the mandible and the other in the maxilla, are reported in young girls 7 and 15 years old. One was a primary lesion; the other was associated with fibrous dysplasia. In both cases CT and MR demonstrated characteristic fluid-fluid levels. The diagnosis was confirmed after biopsy and surgical resection of the lesions.


Investigative Radiology | 1996

RADIOLOGIC ASSESSMENT OF INTRANODAL VASCULARITY IN HEAD AND NECK SQUAMOUS CELL CARCINOMA: CORRELATION WITH HISTOLOGIC VASCULAR DENSITY

Sylvie Lamer; Robert Sigal; Nathalie Lassau; Jacques Bosq; Frédérique Frouin; Mireille Di Paola; G. Mamelle; J. Leclère; J. Bittoun; Robert Di Paola

RATIONALE AND OBJECTIVES Nodal response to chemotherapy in head and neck squamous cell carcinoma depends on the vascularization. The authors assessed different techniques in detecting nodal vascularization. METHODS Fourteen patients with head and neck tumor were included before surgical treatment. The largest metastatic lymph node (mean axial scanographic diameters 30 x 20 mm) was studied by color and pulsed Doppler, and dynamic magnetic resonance images, processed by factor analysis of medical image sequences (FAMIS), which estimates physiologic contrast enhancement kinetics (factors) and their spatial distributions (factor images). Results were compared with the histologic microvessel density (MVD). Using light microscopy, MVD was estimated by the vascular surface (by staining endothelial cells) to the stroma surface ratio x 100. RESULTS Three factors were identified by FAMIS: a constant factor in necrosis, an earlier F1 factor and a later F2 factor in normal lymphoid areas and neoplastic stroma. Color flow signal was detected when the MVD was greater than 6.36. CONCLUSIONS Only one model of vascularization was extracted by FAMIS, with no difference between neoplastic and spared lymphoid areas. The presence of color-flow signals could help predict the response of metastatic lymph nodes to chemotherapy.


Journal De Radiologie | 2005

Comprendre et utiliser le CAD (Aide informatisée au diagnostic) en mammographie

C. Balleyguier; B. Boyer; A. Athanasiou; Daniel Vanel; Robert Sigal

Resume La generalisation du depistage organise du cancer du sein necessite la mise en place de la double lecture qui permet de reduire le taux de faux negatifs du depistage, mais peut etre d’organisation difficile. Les systemes informatiques d’aide au diagnostic (CAD) sont en amelioration constante et sont capables de detecter des images mammographiques suspectes, foyers de microcalcifications, masses ou distorsion architecturale. Des progres sont aussi enregistres dans la caracterisation des masses par CAD. L’objectif de cette mise au point est de faire l’etat des lieux des differents systemes CAD disponibles actuellement, de decrire leurs principes de fonctionnement et de presenter les principaux resultats du CAD en mammographie. En particulier, la place du CAD dans le depistage organise, selon les resultats des dernieres etudes prospectives publiees sera discutee.


Head and Neck-journal for The Sciences and Specialties of The Head and Neck | 2003

Head and neck cancer patients with pulmonary nodules: value and role of CT-guided transthoracic needle aspiration biopsies.

Benoît Mesurolle; François Mignon; Philippe Meingan; C. Domenge; Manuella Vasile; Robert Sigal

To evaluate transthoracic needle aspiration biopsies of pulmonary lesions in patients with squamous cell cancer of head and neck.

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Daniel Vanel

Institut Gustave Roussy

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F. Bidault

Institut Gustave Roussy

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B. Luboinski

Institut Gustave Roussy

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