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Biomedical subjects

P Taourel

Publications and source records attributed to P Taourel.

At least 37 records · Page 2Linked to original sources
PubMed2002

Multicenter study for the evaluation of a dedicated biopsy device for MR-guided vacuum biopsy of the breast.

The purpose of this multicenter study was to determine the accuracy and clinical value of a dedicated breast biopsy system which allows for MR-guided vacuum biopsy (VB) of contrast-enhancing lesions. In five European centers, MR-guided 11-gauge VB was performed on 341 lesions. In 7 cases VB was unsuccessful. This was immediately realized on postinterventional images or direct follow-up combined with histopathology-imaging correlation; thus, a false-negative diagnosis was avoided. Histology of 334 successful biopsies yielded 84 (25%) malignancies, 17 (5%) atypical ductal hyperplasias, and 233 (70%) benign entities. Verification of malignant or borderline lesions included reexcision of the biopsy cavity. Benign histologic biopsy results were verified by retrospective correlation with the pre- and postinterventional MRI and by subsequent follow-up. Our results indicate that MR-guided VB, in combination with the dedicated biopsy coil, offers the possibility to accurately diagnose even very small lesions that can only be visualized or localized by MRI.

Biopsy↗
PubMed2002

European quadricentric evaluation of a breast MR biopsy and localization device: technical improvements based on phase-I evaluation.

Our purpose was to report about technical success, problems and solutions, as experienced in a first multicentre study on MR-guided localisation or vacuum biopsy of breast lesions. The study was carried out at four European sites using a dedicated prototype breast biopsy device. Experiences with 49 scheduled localisation procedures and 188 vacuum biopsies are reported. Apart from 35 dropped indications, one localisation procedure and 9 vacuum biopsies were not possible (3 times space problems due to obesity, 2 times too strong compression, 3 times impaired access from medially, 2 times impaired access due to a metal bar). Problems due to too strong compression were recognised by repeat MR without compression. During the procedure problems leading to an uncertain result occurred in eight vacuum biopsies, two related to the procedure: one limited access, and one strong post-biopsy enhancement. Improvements after phase-I study concerned removal of the metal bar, development of an improved medial access, of a profile imitating the biopsy gun, optimisation of compression plates and improved software support. The partners agreed that the improvements answered all important technical problems.

Biopsy, Needle↗
PubMed2002

Normal vertebral body dimensions: a new measurement method using MRI.

Much clinical research on osteoporosis is aimed at documenting a reduction in vertebral fracture rates, but there is considerable disagreement about defining normality. Most methods for measuring vertebral body dimensions use lateral radiographs. In the present paper, we investigate the reliability of magnetic resonance imaging (MRI) for normal reference determination. A validation study was performed on a cadaver by comparing vertebral body volume measured both with MRI (sagittal acquisition in T1 weighted sequence) and with immersion. MRI was then performed with the same protocol from T4 to L5 in a standard population of 80 women with no history of vertebral fractures. Then all vertebral measurements were standardized relative to each other, and means and standard deviations were calculated using a statistical fitting procedure derived from volume and medial area. The validation study confirmed the reproducibility and accuracy of MRI (intraclass correlation coefficient 0.95). There was a strong correlation between volume and medial area of vertebral bodies (Pearson correlation coefficient 0.95) and a constant relationship between the medial area of vertebral bodies for each subject (coefficient of variation 5.6%). The variations in vertebral body dimensions will allow comparison with pathologic vertebral fractures in further studies. This could be useful for monitoring osteoporosis treatments.

Aged↗
PubMed2002

The clinical value of preoperative wire localization of breast lesions by magnetic resonance imaging--a multicenter study.

To evaluate the clinical value of MRI guided preoperative wire localization of clinically and mammographically occult lesions of the breast. In a multicenter study, we evaluated 132 preoperative MRI guided localizations. Median lesion size evaluated by MRI prior to wire localization was 9mm. MRI guided localization was successfully performed in 96.2% of cases. Median wire deviation from the lesion was 0 (0-10) mm. Moderate bleeding with no further treatment required occurred in three patients. We conclude that MRI guided preoperative wire localization is a safe and accurate procedure in cases of clinically and mammographically occult lesions of the breast.

Adult↗
PubMed2002

[Imaging of complications following hip arthroplasty].

Acute complications include fractures and prosthesis dislocations. Most chronic complications involve mechanical or septic loosening and aggressive granulomatosis. Greater trochanteric pseudarthrosis, periprosthetic soft tissue ossifications or prosthesis conflict with the psoas muscle can also be responsible for groin pain. Most complications are detected with serial plain radiographs, but additional imaging techniques including CT scan and scintigraphy are sometimes necessary for pretreatment diagnosis. Pain generally indicates a complication but aggressive granulomatosis can be asymptomatic, thus warranting systematic annual plain radiographic control.

Acute Disease↗
PubMed2002

[Acute appendicitis: to image or not to image?].

Acute appendicitis is frequently clinically suspected. However, about 50% of emergency room patients with such a diagnosis do not have acute appendicitis and between 20-25% of patients undergoing appendectomy based on clinical diagnosis have a normal appendix. On the other hand, if left untreated acute appendicitis may result in peritonitis. The purpose of this article is to review the indications for imaging patients with clinical suspicion of acute appendicitis, to describe the US and CT features of acute appendicitis, to review the advantages and limitations of US and CT, and to present the differential diagnosis to be considered in patients with right lower quadrant pain.

Acute Disease↗
PubMed2001

Piezoelectric extracorporeal shockwave lithotripsy of distal ureteric calculi: assessment of shockwave focusing with unenhanced spiral computed tomography.

OBJECTIVE: To assess the effects of the interposition of pelvic bones and abdominal gas in the shockwave pathway during piezoelectric extracorporeal shock wave lithotripsy (ESWL) of distal ureteric stones. PATIENTS AND METHODS: The study included 35 patients who were evaluated with unenhanced spiral computed tomography (CT), used according to their positioning during ESWL. The shockwave pathway was simulated on the sagittal and coronal views crossing the ureteric calculi, allowing a theoretical evaluation of the effective shockwave focusing (with no bone or gas interference). Vertical and oblique approaches were statistically compared for bone and gas interposition. RESULTS: Overall, the effective shockwave focusing during in situ piezoelectric ESWL of distal ureteric stones was 71% of the theoretical area. The interposition of bone and gas was significantly lower for an oblique access than for a vertical approach in the sagittal plane (P < 0.001 and 0.03 on the sagittal and coronal views, respectively). Using stepwise logistic regression, the difference between vertical and oblique accesses in the sagittal plane was mainly affected by the bladder volume (P < 0.001). On the coronal views, the interposition of bone and gas affected 31 patients (89%). Such interference was eliminated in 73% of the patients with a contralateral inclination of the shockwave axis in the coronal plane. CONCLUSION: The interposition of pelvic bones and abdominal gas in the shockwave pathway can affect the performance of piezoelectric ESWL of distal ureteric stones. While awaiting clinical confirmation of these theoretical data, we recommend that patients are treated with the bladder full and that the shockwave generator is inclined in both the coronal and sagittal planes.

Adult↗
PubMed1999

Acute pancreatitis: interobserver agreement and correlation of CT and MR cholangiopancreatography with outcome.

PURPOSE: To assess the correlation between and the interobserver agreement of contrast medium-enhanced computed tomography (CT) and nonenhanced and contrast-enhanced magnetic resonance (MR) imaging findings in patients with acute pancreatitis and to correlate these findings with outcome. MATERIALS AND METHODS: Two blinded reviewers separately assessed contrast-enhanced CT and nonenhanced and contrast-enhanced MR images in 30 patients with acute pancreatitis and established a severity index based on the presence of peripancreatic fluid collections and pancreatic necrosis. The Spearman rank correlation coefficient and weighted kappa statistic were used to assess the correlation between each imaging technique and the interobserver agreement, respectively. Correlation between hospitalization days, morbidity, and severity indexes were assessed by using linear correlation. RESULTS: A strong correlation existed for both reviewers when comparing contrast-enhanced CT with nonenhanced (r = 0.82, 0.79) or contrast-enhanced (r = 0.82, 0.79) MR cholangiopancreatography or when comparing nonenhanced and contrast-enhanced MR cholangiopancreatography (r = 0.99, 1.00). The interobserver agreement in staging was stronger with nonenhanced (kappa = 0.76) and contrast-enhanced (kappa = 0.78) MR cholangiopancreatography than with contrast-enhanced CT (kappa = 0.70). There was no linear correlation between the severity index for contrast-enhanced CT and outcome, while there was a linear correlation between nonenhanced or contrast-enhanced MR cholangiopancreatographic staging and the patient morbidity rate. CONCLUSION: MR cholangiopancreatography could be an alternative to contrast-enhanced CT for the initial staging of acute pancreatitis.

Acute Disease↗
PubMed1999

Hepatic intraarterial 131I iodized oil for treatment of hepatocellular carcinoma in patients with impeded portal venous flow.

PURPOSE: To evaluate the efficacy and safety of intraarterial hepatic iodine 131 iodized oil for treatment of hepatocellular carcinoma in patients with impeded portal venous flow. MATERIALS AND METHODS: Twenty-four patients (mean age, 61 years) with hepatocellular carcinoma underwent 38 courses of 131I iodized oil (one to three per patient), with a mean dose of 2,146 MBq injected into the proper hepatic artery. Hepatocellular carcinoma manifested as single nodules (n = 8; mean, 7.75 cm), multiple nodules (n = 13; mean, 5.46 cm), or a mass (n = 3) occupying more than two hepatic segments. Portal venous thrombosis was complete (n = 10), right (n = 9), left (n = 2), or multisegmental (n = 1). Two patients had hepatofugal portal flow. RESULTS: Among the 23 patients with evaluable results, response to treatment was partial in three, and disease was stable in 12 and progressive in eight. Estimated actuarial survival rates were 70%, 33%, 12%, and 6% at 3, 6, 9, and 12 months, respectively, with two patients alive at 9 and 11 months. The median survival time was 147 days. Adverse events were the early death of one patient owing to hepatic failure and transient symptomatic hepatic failure after 12 courses in nine patients. CONCLUSION: In this preliminary experience, intraarterial hepatic 131I iodized oil did not demonstrate high efficacy in the treatment of hepatocellular carcinoma in patients with portal venous thrombosis, as side effects were not rare.

Aged↗
PubMed1999

Acute osteoporotic vertebral collapse: open study on percutaneous injection of acrylic surgical cement in 20 patients.

OBJECTIVE: The aim of this study was to determine the efficacy of percutaneous vertebroplasty in treating painful spinal osteoporotic collapse. SUBJECTS AND METHODS: Twenty-three cases of vertebral collapse were evaluated with CT and MR imaging to determine osteoporotic origin and recent evolution. Percutaneous vertebroplasties were performed using CT guidance. The 20 patients included in the study (17 women, 3 men; 62-92 years old) had acute pain of less than 1 month's duration that hindered ambulation and required treatment with narcotic drugs. They underwent this procedure for analgesic purposes. The analogic visual scale of Huskisson was used for pain when scoring assessment. RESULTS: In 15 patients (75%), pain relief was complete within 24 hr after injection. Analgesic administration was stopped in 14 patients. Mild pain persisted in three (15%) of the remaining five patients. In one other patient (5%), crural pain was observed with cement leakage in the psoas muscle. In the fifth patient (5%), pain recurred after the patient was lifted. The pain was related to a new acute collapse of an adjacent vertebrae. CONCLUSION: Vertebroplasty for the treatment of osteoporotic vertebral collapse is a minimally invasive procedure that provides immediate pain relief and enables the patient to become quickly mobile.

Acrylic Resins↗
PubMed1999

[Needle-tract seeding after ultrasound-guided puncture of hepatocellular carcinoma. A study of 150 patients].

OBJECTIVES: To study the frequency of tumor seeding after percutaneous biopsy of hepatocellular carcinoma and to evaluate the impact on long-term survival. METHODS: Records of 150 patients with cirrhosis who underwent ultrasound-guided aspiration biopsy for hepatocellular carcinoma between 1989 and 1996 were reviewed in June 1998. Liver transplantation was performed in 7 patients. One to three needle passes were performed with 18 to 20 gauge needles. Follow-up included regular clinical examinations and ultrasonography or computerized tomography. RESULTS: Four cases (2.66%) of subcutaneous metastasis were noted at the needle insertion site; none in transplanted patients. All patients had viral cirrhosis, Okuda class I. Nodules were detected 4, 12, 22 and 24 months after biopsy. The second patient is alive 24 months after tumor seeding. For other patients, survival time was 4, 24 and 60 months respectively, without local tumor extension after surgical resection or radiotherapy. During a mean 11.8 months of follow-up, 127 patients died without tumor seeding. Eleven patients are still being followed and have no signs of needle tract implantation of hepatocellular carcinoma (mean follow-up 34.7 months). CONCLUSION: The prevalence of tumoral seeding after percutaneous biopsy of hepatocellular carcinoma was 2.66%, which is higher than in previous studies. After liver transplantation, no evidence of needle tract seeding was identified. Survival did not seem to be influenced by local evolution.

Adult↗
PubMed1998

Doppler study of mesenteric, hepatic, and portal circulation in alcoholic cirrhosis: relationship between quantitative Doppler measurements and the severity of portal hypertension and hepatic failure.

To determine the relationship between quantitative Doppler parameters of portal, hepatic, and splanchnic circulation and hepatic venous pressure gradient (HVPG), variceal size, and Child-Pugh class in patients with alcoholic cirrhosis, we studied forty patients with proved alcoholic cirrhosis who underwent Doppler ultrasonography, hepatic vein catheterization, and esophagoscopy. The following Doppler parameters were recorded: time-averaged mean blood velocity, volume flow of the main portal vein flow, and resistance index (RI) of the hepatic and of the superior mesenteric artery. Doppler findings were compared with HVPG, presence and size of esophageal varices, and Child-Pugh class. There was a significant inverse correlation between portal velocity and HVPG (r = -.69), as well as between portal vein flow and HVPG (r = -.58). No correlation was found between RI in the hepatic artery or superior mesenteric artery and HVPG. No correlation was found between portal vein measurements and presence and size of varices. Severe liver failure was associated with lower portal velocity and flow. In patients with alcoholic cirrhosis, only portal vein blood velocity and flow, but neither hepatic nor mesenteric artery RI, are correlated to the severity of portal hypertension and to the severity of liver failure.

Adult↗