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C Roy

Publications and source records attributed to C Roy.

At least 19 recordsLinked to original sources
PubMed2006

Arterial phase enhancement and body mass index are predictors of response to chemoembolisation for liver metastases of endocrine tumours.

Transcatheter arterial chemoembolisation (TACE) has been reported to be an efficient treatment of liver metastases of endocrine tumours in short series of patients. However, several factors seem to affect its results. The aim of this work is to identify predictors of response to TACE for liver metastases of endocrine tumours. A total of 163 TACE procedures were performed in 67 patients between 1994 and 2004. Forty-four patients were treated with streptozotocin and 23 with doxorubicin. Primary tumour was located in the pancreas for 19 patients, and had been removed in 43. Thirty-eight tumours were functioning. Response rate was 37% (confidence interval [CI] 95%: 28-49%). Median time to progression (TTP) was 14.5 months (CI 95%: 9-41). In multivariate analysis (n=43), predictors of tumour response were body mass index (BMI) (odds ratio [OR]: 1.3; CI 95%: 1.04-1.63; P=0.022), functioning type of tumour (OR: 7.31; CI 95%: 1.26-42.5; P=0.027), arterial phase enhancement on abdominal computed tomography (CT) (OR: 8.11; CI 95%:1.06-62; P=0.044) and use of streptozotocin for cytotoxic agent (OR: 21.3; CI 95%: 1.48-306; P=0.025). Analysis of TTP predictors showed that BMI (hazard ratio [HR]: 0.85; CI 95%: 0.76-0.86; P=0.01) and arterial phase enhancement (HR: 0.3; CI 95%: 0.12-0.73; P=0.008) were associated with delayed progression. This large study confirms the previously reported results of TACE regarding its efficacy for the treatment of liver metastases of endocrine tumours. Arterial phase enhancement on abdominal CT and BMI are predictors of treatment's efficacy. Streptozotocin should be the preferred cytotoxic agent in order to save anthracycline for systemic chemotherapy.

Adult↗
PubMed2006

[Imaging of urinary lithiasis: "all in one"].

Urinary lithiasis is very common among the general population, with a high prevalence level. In rich countries it is mainly located inside the upper urinary tract. Helical CToperated with newer devices is the most accurate modality to provide all needed information: diagnosis of stone without contrast medium injection, morphology (size, number) and localization, diagnosis of urinary obstruction, urinary tract aspect and all kind of differential diagnosis in emergency. It must be used during follow up to diagnose residual fragments. Multiplanar reconstructions are essential for the clinicians; but diagnosis is interpreted by scrolling axial views with dynamic analysis on computer screen. Low-dose helical CT is today available. Helical CT provides an "all-in-one" examination. It should soon replace combined plain film-ultrasonography performed in an emergency context of renal colic and intravenous urography for pre- and post-treatment assessments.

Decision Trees↗
PubMed2006

[Treatments of prostate carcinoma and imaging follow up].

Multiple treatments are proposed to cure prostate carcinoma. Radical prostatectomy is the classical option for localized tumor. However radiotherapy can be proposed in such circumstances with the argument of a less invasive procedure with similar results. High Intensity Focalised Ultrasound (HIFU) is a new technique available for similar staging of the carcinoma with good results. Follow up is based on biological evaluation of PSA. Imaging studies are required only in cases of abnormal level. Endorectal Ultrasonography with biopsies is useful after radical surgery. Indications for MRI study is mainly to differentiate a localized from a general recurrence.

Aged↗
PubMed2006

[Renal tumors].

This pictural essay presents the different imaging patterns of the main renal tumor processes described in the latest pathological classification. Most of them make it possible to suggest certain histological types in order to modify the surgical approach.

Adult↗
PubMed2004

Acute torsion of uterine leiomyoma: CT features.

Acute torsion of a subserosal leiomyoma is a rare acute condition that is infrequently diagnosed preoperatively. It is a recognized surgical emergency, especially when additional systemic symptoms are associated. There are two main differential diagnoses: ovary/adnexal torsion and massive infarct inside a common leiomyoma. The diagnosis can be established by computed tomographic features. Ultrasound examination is less sensitive.

Adult↗
PubMed2004

Interferometry of direct photons in central 208Pb + 208Pb collisions at 158A GeV.

Two-particle correlations of direct photons were measured in central 208Pb+208Pb collisions at 158A GeV. The invariant interferometric radii were extracted for 100<K(T)<300 MeV/c and compared to radii extracted from charged pion correlations. The yield of soft direct photons, K(T)<300 MeV/c, was extracted from the correlation strength and compared to theoretical calculations.

Journal Article↗
PubMed2004

[MRI of the urinary tract: recent developments and future applications].

New fast MR imaging sequences obtained with high power gradients allow dynamic analysis of parenchymal enhancement by contrast media in order to improve characterization of masses as well as a functional analysis. Phased - array coils have greatly improved spatial resolution. MR Urography is a new valuable modality to study the collecting system. Numerous acronyms are proposed with a wide range of variations between different machines. But basic principles for sequences are similar. MR can be performed in patients with renal insufficiency, iodine allergy or any other contra-indication to the use of ionizing radiation. MRI of the kidney is becoming a major imaging modality to diagnose diseases of the kidney. It provides in a rather short time a "all-in-one approach" of the pathological process.

Adenoma, Oxyphilic↗
PubMed2004

Accuracy of conventional cytology: results from a multicentre screening study in India.

OBJECTIVE: We conducted a multi-centre cross-sectional study in India to evaluate the accuracy of conventional cytology to detect high-grade squamous intraepithelial lesions (HSIL). SETTING: Cross-sectional studies in Jaipur, Kolkata, Mumbai and Trivandrum, India, during 1999-2003. METHODS: A common protocol and questionnaire were used to test 22,663 women aged 25-65 years with conventional cytology in five cross-sectional studies. Three thresholds were used to define test positivity: atypical squamous cells of uncertain significance (ASCUS), low-grade squamous intra-epithelial lesion (LSIL), or HSIL. All screened women were investigated with colposcopy, and biopsies were taken when necessary. The reference standard for final disease status was histology or negative colposcopy. Data from the studies were pooled to evaluate the test characteristics for the detection of histologically confirmed HSIL. RESULTS: The test positivity rates of cytology were 8.8% at ASCUS, 6.2% at LSIL and 1.8% at HSIL thresholds, and 355 women had histologically confirmed HSIL while 74 had invasive cancer. The pooled sensitivity, specificity, positive and negative predictive values at ASCUS threshold were 64.5%, 92.3%, 11.8% and 99.4% respectively. The corresponding values at LSIL threshold were 58.0%, 94.9%, 15.2% and 99.3%, while at the HSIL threshold they were 45.4%, 99.2%, 46.3% and 99.1%. The sensitivity varied between 37.8-81.3% at ASCUS, 28.9-76.9% at LSIL and 24.4-72.3% at HSIL thresholds. A significantly low sensitivity was observed in women aged 25-39 years (p<0.001). The wide variation in sensitivity across study sites persisted even after age standardisation. CONCLUSION: The sensitivity of cytology varied widely between the study sites. Findings from our study and other reviews indicate that sustained efforts in improving sampling, preparation and reading of cytological specimens and improvements in clinical judgement are essential to achieve concurrently high sensitivity and specificity.

Adult↗
PubMed2003

Recycling of meat and bone meal animal feed by vacuum pyrolysis.

Due to the recent bovine spongiform encephalopathy (BSE) crisis in the European beef industry, the use of animal-derived products to feed cattle is now severely restricted. Large quantities of waste animal meat and bone meal (MBM), also known as animal flour, have to be safely disposed of or transformed. One disposal option is pyrolysis. Vacuum pyrolysis of an animal flour sample has been performed in a laboratory reactor. The results obtained revealed that vacuum pyrolysis can be an attractive alternative to incineration and cement kilns. The process generated a combustible gas (15.1 wt %), a high calorific value oil (35.1 wt %), a solid residue rich in minerals (39.1 wt %), and an aqueous phase rich in organics (10.7 wt %). The gas and the aqueous phase can be used to provide heat to the vacuum pyrolysis reactor and the MBM drying unit. The oil can be used alone or mixed with petroleum products as a fuel in boilers or gas turbines. Conversion of animal waste by pyrolysis into fuels can contribute to the reduction of greenhouse gases. It is suggested to use the solid residue for agricultural soil enrichment in minerals and as a soil moisturizer.

Abattoirs↗
PubMed2003

Naloxone for shock.

BACKGROUND: There is pre-clinical evidence, involving several animal species, suggesting that opioid peptides play a role in the physiopathology of shock (endotoxic, hypovolemic, cardiogenic, spinal, anaphylactic). Many case reports have suggested that naloxone (an opiate antagonist) might be an effective treatment for shock in humans, but others have not supported such a point of view. This controversy led us to undertake a meta-analysis of the available evidence on the efficacy of naloxone as a treatment measure of shock in humans. OBJECTIVES: To evaluate the effectiveness and safety of naloxone in human shock and to estimate the methodological quality of the clinical trials. SEARCH STRATEGY: Computerized bibliographic search up to December 2002, review of references of all papers found on the subject and contact with primary investigators of eligible studies. SELECTION CRITERIA: Randomized controlled trials evaluating naloxone in human shock, regardless of the patient's age (adult, child or neonate). DATA COLLECTION AND ANALYSIS: Three independent reviewers extracted data on study design, intervention, outcome and methodological quality. MAIN RESULTS: Three independent readers reviewed 80 human publications and selected six clinical trials. Overall agreement on study selection was perfect (concordance: 100%). This meta-analysis includes six studies involving 126 patients with septic, cardiogenic, hemorrhagic or spinal shock. Naloxone therapy was associated with statistically significant hemodynamic improvement (odds ratio 0.24; 95% confidence interval [95%CI] 0.09-0.68). The mean arterial pressure was significantly higher in the naloxone groups than in the placebo groups (weighted mean difference: +9.33 mmHg; 95%CI 7.07-11.59). No heterogeneity was found for this outcome. The death rate was lower in the naloxone group (odds ratio 0.59; 95%CI 0.21-1.67) but this was consistent with the play of chance. A significant heterogeneity for the latter outcome was detected (p<0.05). REVIEWER'S CONCLUSIONS: Naloxone improves blood pressure, especially mean arterial blood pressure. However, the clinical usefulness of naloxone to treat shock remains to be determined, and additional randomized controlled trials are needed to assess its usefulness.

Adult↗
PubMed2003

[Urinary obstruction: different radio-clinical types].

Urinary obstruction has three different clinical aspects: acute, chronic and intermittent. Imaging modalities and diagnostic strategies are different for each of them. Although the morphologic analysis is accurate for all imaging modalities, the diagnosis of hydronephrosis may not be so easy, except for major typical form. There are some pitfalls, for instance the presence of parapelvic cysts at ultrasound and difficulties for initial or minor forms. Nowadays, IVU is still in routine the best examination to assess renal function. In the near future, MRI should be able to give useful information for both morphologic and functional status and take an important role in the evaluation of urinary obstruction.

Chronic Disease↗
PubMed2003

[Scrotal ultrasound. Part II: Cysts, tumors and rare non tumoral processes].

Pathological processes of the scrotum are very numerous. They are composed by few common well known diseases and a large spectrum of rare lesions. The testis may be involved by some systemic diseases. Ultrasound is the main modality for scrotal imaging and complementary to clinical evaluation. When a tumoral process is suspected, surgery is required to confirm the diagnosis and provide histology. The role of MR remains under evaluation.

Cysts↗
PubMed2003

[Scrotal ultrasonography. Part I: common non-cancerous pathologies].

Pathological processes of the scrotum are very numerous. They are composed by few common well known diseases and a large spectrum of rare lesions. The testis may be involved by some systemic diseases. Ultrasound is the main modality for scrotal imaging and complementary to clinical evaluation. When a tumoral process is suspected, surgery is required to confirm the diagnosis and provide histology. The role of MR remains under evaluation.

Abscess↗
PubMed2002

[Imaging and pathology of bladder tumors].

Epithelial bladder tumors are very common. Multiple lesions are possible with variable degrees of malignant potential. Benign and mesenchymal tumors are much less frequent. The role of imaging is to first raise the possibility of such a tumor and then to provide pretreatment staging. Cystoscopy with tumoral resection and histological diagnosis remains essential for adequate treatment selection. Ultrafast MR imaging may be very valuable for evaluation of these tumors. Posttreatment follow-up is needed to detect recurrent tumors. Intravenous urography remains valuable for evaluation of the upper tracts.

Aftercare↗