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D Brisbois

Publications and source records attributed to D Brisbois.

10 recordsLinked to original sources
PubMed2002

Duplex ultrasound as first-line screening test for patients suspected of renal artery stenosis: prospective evaluation in high-risk group.

Our objective was to assess how far the progress in ultrasound devices has increased feasibility and accuracy of Duplex ultrasound (DUS) for the diagnosis of renal artery stenosis (RAS), in a population with high prevalence of atherosclerotic renovascular lesions. Ninety-one hypertensive patients with atherosclerotic disease were prospectively evaluated by both DUS and digital subtraction angiography (DSA) of the renal arteries. Only proximal criteria (peak systolic velocity >180 mm/s or renal-to-aortic ratio >3.5) were used for the diagnosis of significant RAS (>60% narrowing). For both techniques, two readers were involved for interobserver variability study. Two hundred one arteries were demonstrated by DSA on 182 available kidneys. The prevalence of RAS among the study group was 37%. Sixteen of the 19 accessory arteries were not seen at DUS; in 8 patients, one renal artery was not seen at DUS (feasibility 91%). On the 177 arteries assessed, in comparison with DSA, DUS yielded 96, 91, and 97% mean values of accuracy, sensitivity, and specificity, respectively. Kappa for interobserver agreement was 0.95 for DUS and 0.92 for DSA. Although still unreliable for the detection of accessory arteries, DUS is in our experience an accurate and reproducible diagnostic test for RAS.

Angiography, Digital Subtraction↗
PubMed2001

[Value of MRCP for detection of choledocholithiasis in symptomatic patients: one-year experience with a standardized high resolution breath-hold technique].

In our institution, MRCP is actually replacing diagnostic ERCP. This study is addressing its accuracy in the diagnosis of symptomatic choledocholithiasis. 137 MRCP were performed in patients with upper abdominal pain and biological anomalies (n = 48), pain with cholelithiasis at sonography (n = 69) or non-alcoholic acute pancreatitis (n = 20) on a 1.5 T system with high gradients using a standardized combination of breath-hold HASTE and RARE sequences. We included in our study 74 patients who underwent as second test ERCP (n = 36), peroperative cholangiography (n = 13), or extensive follow-up with laboratory tests and/or sonography (n = 25). All examinations were judged as diagnostic, discrepancies between direct cholangiography and MRCP being noted in 4 patients (5.4%). Lithiasis was misinterpreted on MRCP as bubbles in 2 patients after sphincterotomy or surgery. We had two false positive diagnoses on MRCP: in one patient peroperative cholangiography was negative and in the other one ERCP was negative. With a sensitivity and PPV of 92%, a specificity and NPV of 96% MRCP in our experience is shown as an accurate diagnostic tool for the detection of stone in the common bile duct replacing ERCP.

Adolescent↗
PubMed2000

[State of the art of pancreatic cancer imaging].

Ultrasonography and CT-scanner remain the first choice nowadays concerning detection and preoperative work-up of pancreatic cancer. MRI offers interesting options for the detection of liver metastases, and high quality of ductal and vascular examination. Actually, while we await a larger diffusion of MR systems and radiological expertise this technique is preferentially indicated as a third-step procedure when ultrasonography and CT-scanner are normal despite a real suspicion. Otherwise, MRI permits with a single non-invasive examination a complete work-up useful to prepare palliative therapy in case of unresectable tumor.

Humans↗
PubMed2000

[Carotid endarterectomy without arteriography: only dedicated to urgent procedures?].

Duplex examination is presently established as a safe non-invasive and accurate method of evaluating patients with extracranial cerebrovascular disease which usually provides complete information about the extent of carotid artery narrowing Arteriography, in this indication, is an invasive procedure with a total complication rate of 3-4% with 1% of permanent stroke. If it is currently accepted that in emergency conditions (ictus ingravescens, pre-occlusive plaque) or if iodinated contrast media are contraindicated, thrombendarteriectomy can be performed without arteriography it could be extended to most cases. The authors stress the criteria to increase the number of those patients, summarize the pre-requisites to achieve this goal, and comment on the future alternative position of MRA.

Angiography↗
PubMed1998

Relevant radiological anatomy of the pig as a training model in interventional radiology.

The use of swine for teaching purposes in medicine and surgery has largely increased in recent years. Detailed knowledge of the porcine anatomy and physiology is a prerequisite for proper use of pigs as a teaching or an experimental model in interventional radiology. A systematic study of the radiological anatomy was undertaken in more than 100 female pigs aged 6-8 weeks. All studies were performed under general anesthesia in a single session. Animals were sacrificed at the end of the study. Selective angiographies were systematically obtained in all anatomical territories. In other animals CT and MRI examinations were performed and were correlated to anatomical sections and acrylic casts of the vascular structures. Endoscopical examinations of the upper gastrointestinal tract, including retrograde opacification of the biliary and pancreatic ducts, were added in selected animals. The main angiographic aspects of the brain, head and neck, thorax, abdomen, and pelvis were recorded. Similarities and differences in comparison with human anatomy are stressed. Potential applications in interventional radiology are indicated.

Animals↗
PubMedDate not supplied

[MR aortofemorography versus DSA: prospective evaluation].

PURPOSE: To determine how far MRA of lower limbs obviates the need for pre-therapeutic DSA. MATERIALS AND METHOD: Three-step 3-D gadolinium enhanced aortofemorography with a moving bed was prospectively compared to DSA in 49 consecutive patients (40 males, 9 females; age range 38-80 years; mean age 64 years). According to Leriche and Fontaine's clinical gradation of lower limb ischemia, 5 patients were graded I, 37 graded II, 4 graded III, and 3 graded IV. Two observers graded stenoses for DSA and three for MRA. Cohen's kappa statistics were used to evaluate interobserver variability using MRA, as well as to compare MRA to DSA. In addition, sensitivity, specificity, positive and negative predictive values of MRA for the assessment of stenosis superior to 80% were calculated by using DSA as a gold standard, respectively for arterial trunks above and below the level of the knees. RESULTS: Overall accuracy of MRA was 92%. Comparison of DSA and MRA yielded a kappa value of 0.87 (0.95 for arterial trunks located above the level of the knees and 0.75 below). Interobserver agreement was very good. Sensitivity, specificity, positive and negative predictive values of MRA for the diagnosis of > 80% stenosis were respectively 98, 98, 85 and 99% above the level of the knees and 87, 91, 77 and 96% below the knees. CONCLUSION: MRA can be considered as valuable technique for the evaluation of peripheral arterial obstructive disease, especially for stenosis located above the level of the knees.

Angiography, Digital Subtraction↗
PubMedDate not supplied

Acute abdomen. Is ultrasonography useful, essential or unnecessary?

Abdominal ultrasonography in acute conditions gives sometimes the definite diagnosis or at least indicates a strategy for further examinations. This technique is constantly accurate for the upper part of the abdomen, and its classical indications are dominated by cholecystitis, biliary and urinary lithiasis, pancreatic and aortic painful circumstances. However, its role has been emphasized recently, after famous publications about the usefulness of high resolution ultrasonography for appendicitis and various gut-related acute conditions. The efficacity of abdominal ultrasonography is enhanced by color-doppler and power-doppler, to characterize some inflammatory or ischemic diseases. For the pelvis, endocavitary examination is a "must" for studying uterus and adnexae. The main drawbacks of abdominal ultrasonography are well known: its physical limitations and mainly its operator-dependence.

Abdomen, Acute↗