Biomedical subjects

Robert Sigal

Publications and source records attributed to Robert Sigal.

11 recordsLinked to original sources

PubMed2006

BIRADS classification in mammography.

The Breast Imaging Report and Data System (BIRADS) of the American College of Radiology (ACR) is today largely used in most of the countries where breast cancer screening is implemented. It is a tool defined to reduce variability between radiologists when creating the reports in mammography, ultrasonography or MRI. Some changes in the last version of the BIRADStrade mark have been included to reduce the inaccuracy of some categories, especially for category 4. The BIRADStrade mark includes a lexicon and descriptive diagrams of the anomalies, recommendations for the mammographic report as well as councils and examples of mammographic cases. This review describes the mammographic items of the BIRADS classification with its more recent developments, while detailing the advantages and limits of this classification.

Breast Neoplasms↗

PubMed2006

BIRADS mammography: exercises.

Some radiological cases are presented in this article to train the reader to the BIRADS classification in mammography. Each case is described according to the fourth American version of the BIRADS lexicon. Some classifications difficulties will also be presented, in order to show the complexity and the observer variability, commonly encountered in BIRADS 3 and 4 categories.

Aged↗

PubMed2006

Cine magnetic resonance imaging with single-shot fast spin echo for evaluation of dysphagia and aspiration.

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.

Adult↗

PubMed2006

Evaluation of tumor angiogenesis of breast carcinoma using contrast-enhanced digital mammography.

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.

Adult↗

PubMed2006

[Retroperitoneal sarcomas imaging].

Retroperitoneal sarcomas are rare neoplasms. The aim of this article is to expose imaging protocols and useful radiological signs, to show the core biopsy technique for diagnosis, to precise imaging key points before treatment and for survey.

Biopsy, Needle↗

PubMed2005

Detection of liver metastases from endocrine tumors: a prospective comparison of somatostatin receptor scintigraphy, computed tomography, and magnetic resonance imaging.

PURPOSE: To compare the respective sensitivity of somatostatin receptor scintigraphy (SRS), computed tomography (CT), and magnetic resonance imaging (MRI) in the detection of liver metastases from well-differentiated gastroenteropancreatic endocrine tumor (WDGEP ET) patients. To define predictive factors for "high-sensitivity SRS." PATIENTS AND METHODS: Sixty-four patients with WDGEP ET underwent SRS with abdominal single-photon emission computed tomography (SPECT), spiral CT, and 1.5-T MRI within a 15-day interval, the order of which was randomized. Two readers analyzed images of each modality, blindly and independently. RESULTS: Hepatic metastases were present in 40 of the 64 patients and confirmed by pathology after liver biopsy or surgery in 32 and eight patients, respectively. SRS, CT, and MRI detected a total of 204, 325, and 394 metastases, respectively. The number of detected metastases was significantly higher with MRI than with CT (P = .02) and SRS (P < 10(-4)) and higher with CT than with SRS (P < 10(-4)). SRS was negative in seven patients with a positive CT and/or MRI. More lesions were detected in 10 patients by SPECT compared with static views. The median metastasis size was significantly correlated (P = .04) with the sensitivity of SRS. CONCLUSION: MRI seems to have an edge over CT and SRS for the detection of liver metastases from endocrine tumors. We recommend the systematic performance of liver MRI at WDGEP ET initial staging and before major therapeutic events. The low performance of SRS was mainly explained by the impact of the metastasis size on the detection capacity of SRS.

Adolescent↗

PubMed2003

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

BACKGROUND: To evaluate transthoracic needle aspiration biopsies of pulmonary lesions in patients with squamous cell cancer of head and neck. METHODS: Retrospective series of 85 patients with squamous cell cancer of head and neck cancer and pulmonary nodules who underwent CT-guided needle aspiration biopsy. RESULTS: Diagnostic samples were obtained in 85% of patients. There were 8 benign and 77 malignant lesions. Among the 73 proved cases, 4 were false-negative cases. CT-guided biopsy had an accuracy of 81%, a sensitivity of 94%, and a negative predictive value of 60%. Accuracies were 68% for lesions of 20 mm or smaller and 89% for lesions greater than 20 mm. In a subset of 45 solitary lesions, among 30 positive biopsies, 15 were categorized as primary malignancies, 3 as metastatic, and 12 as indeterminate malignancies. CONCLUSIONS: In head and neck cancer patients, the prevalence of thoracic malignancies is high when a pulmonary lesion is detected. CT-guided biopsy of pulmonary lesion is an accurate procedure. However, a third of positive biopsies were categorized as indeterminate malignancies.

Adult↗

PubMed2003

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

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.

Adult↗

PubMed2003

MR imaging of hepatic metastases caused by neuroendocrine tumors: comparing four techniques.

OBJECTIVE: The aim of our prospective study was to assess the MR imaging characteristics of hepatic metastases of neuroendocrine tumors and to determine the optimal MR sequence for their detection. SUBJECTS AND METHODS: Thirty-seven consecutive patients with liver metastases from neuroendocrine tumors underwent 1.5-T MR imaging of the liver comprising T2-weighted fast spin-echo with respiratory monitoring, breath-hold T2-weighted single-shot fast spin-echo, and T1-weighted gradient-recalled echo sequences before and after the injection of gadoterate dimeglumine. Images were reviewed independently by three observers for the number, location, and pattern of signal and enhancement of metastases. RESULTS: A total of 359 metastases were detected, 279 on T2-weighed fast spin-echo, 231 on T2-weighed single-shot fast spin-echo, 272 on unenhanced T1-weighted, 322 on hepatic arterial phase, and 228 on portal venous phase images. Hepatic arterial phase images revealed the greatest number of metastases in 70% of patients, including 35 metastases seen only on this sequence, and was significantly superior to the unenhanced T1-weighted and portal venous phase sequences (p < 0.01). The lesion-to-liver contrast was significantly greatest with T2-weighed fast spin-echo sequences. The enhancement patterns of metastases were predominantly hypervascular, hypovascular, peripheral with progressive fill-in, and delayed in, respectively, 27, four, four, and two patients. Most metastases with peripheral enhancement and progressive fill-in were heterogeneous on T2-weighted images and were without globular peripheral enhancement. CONCLUSION: Hepatic metastases of neuroendocrine tumors had a typical hypervascular pattern in 73% of patients. Hepatic arterial phase and fast spin-echo T2-weighed sequences are the most sensitive.

Adult↗

PubMed2002

Hepatic tumors treated with percutaneous radio-frequency ablation: CT and MR imaging follow-up.

PURPOSE: To describe the appearance of hepatic tumors treated with radio-frequency (RF) ablation on computed tomographic (CT) and magnetic resonance (MR) images and the pattern of residual tumor at the site of RF ablation and to assess prospectively the sensitivity, specificity, and positive and negative predictive CT and MR imaging values in the evaluation of RF treatment. MATERIALS AND METHODS: Thirty-one patients with 50 tumors (nine hepatocellular carcinomas and 41 metastases) treated with RF ablation underwent CT and MR imaging on the same day at 2, 4, and 6 months; CT was performed every 3 months thereafter. CT and MR findings were interpreted separately and prospectively by two reviewers with consensus. For both imaging techniques, appearance of the treated area, treatment efficacy, and complications were assessed at each time. Sensitivity and specificity were determined by using the McNemar test. RESULTS: After a mean follow-up of 19 months, nine tumors showed local regrowth. At 2 months, MR imaging depicted more local regrowths (eight of nine; sensitivity, 89%) than did CT (four of nine; sensitivity, 44%) but without significant differences (P =.12). In two cases, only T2-weighted imaging depicted local regrowth. All nine lesions became conspicuous at 4-month follow-up with both techniques. At 2 months, thin peripheral rim enhancement and arterioportal shunting were found in 24% and 12%, respectively, of the treated tumors. These findings disappeared thereafter and are not linked to tumor regrowth. CONCLUSION: Despite the small number of patients, CT and MR imaging may depicted all local regrowth at 4 months or sooner. MR imaging may have an edge over CT in the early detection of local regrowth.

Adult↗

PubMedDate not supplied

Computed tomographic features of peritoneal carcinomatosis treated by intraperitoneal chemohyperthermia.

PURPOSE: The purpose of this work was to describe the computed tomography (CT) features of peritoneal carcinomatosis after surgery combined with intraperitoneal chemohyperthermia (IPCH). METHOD: Between 1999 and 2001, 51 consecutive patients (33 women and 18 men, with a mean age 45 years) were treated in our institution with IPCH for peritoneal carcinomatosis. Patients that were symptomatic (33 patients) underwent contrast enhanced helical CT of the abdomen and the pelvis during the first 15 postoperative days. The CT scans were reviewed retrospectively by two blinded observers. Computed tomography abnormalities were compared with surgical, biochemical, and clinical findings. RESULTS: None of the CT scans were completely normal. Most postsurgical CT findings, including bowel and peritoneal thickening (14 and 13 cases, respectively), increased intraperitoneal fat density (13 cases), and compartmentalized ascites (8 cases), resulted from an inflammatory mesenteric reaction or inflammation of the small bowel or the peritoneum and did not require specific treatment. Major complications requiring appropriate treatment were intra-abdominal abscesses (5 cases), hemoperitoneum (5 cases), urinary fistula (2 cases), acute pancreatitis (1 case) and abdominal wall abscesses (2 cases). CONCLUSION: Knowledge of early CT findings after therapy with surgery combined with IPCH for peritoneal carcinomatosis is useful for accurate posttreatment management of these patients.

Adenocarcinoma↗