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R Houdart

Publications and source records attributed to R Houdart.

At least 19 recordsLinked to original sources
PubMed1995

Predicting common bile duct lithiasis: determination and prospective validation of a model predicting low risk.

BACKGROUND: The aim of this two-part prospective study was: (1) to identify simple, noninvasive, preoperative factors associated with low or very low risk of common bile duct lithiasis (CBDL); and (2) to test the validity of the statistical model obtained during Part One by the postcholecystectomy follow-up of patients classified into a low-risk group. PATIENTS AND METHODS: In Part One of the study, preoperative clinical, biologic, and ultrasonographic data, and intraoperative cholangiographic findings were collected from 503 consecutive patients undergoing cholecystectomy for symptomatic lithiasis from 1985 to 1989. Using the data obtained in Part One, a linear logistic model was used prospectively in Part Two to determine the prediction of absence of CBDL in 279 consecutive patients. No jaundice, normal transaminase levels, common bile duct (CBD) diameter < 8 mm, and no intrahepatic duct enlargement defined the low-risk group of CBDL. RESULTS: In Part One, CBDL was present in 84 (17%) of all patients. Five parameters were used to classify 73% of all patients as low risk of CBDL and 27% as high risk. In the low-risk groups, CBDL was present in 1% of 116 cases with acute gallbladder complications, and 5% of 250 cases with no acute gallbladder complications. In Part Two, 171 (61%) patients were classified in the low-risk group (Group 1), and CBD stones were not sought by any additional preoperative investigations or intraoperative cholangiography (IOC). One hundred eight patients (39%) were considered at risk of CBDL (Group 2). Mean follow-up was 20.6 months (median 19); 2 patients (1%) in the low-risk group presented a symptomatic retained stone. CONCLUSIONS: This study validated this simple model for predicting risk of CBDL and avoiding invasive preoperative investigations--as well as IOC--in more than 60% of symptomatic cholelithiases. In addition, this model seemed useful for defining patients in whom further exploration for CBDL was justified, since 42 (39%) of the 108 Group 2 patients were proved to have CBDL.

Analysis of Variance↗
PubMed1991

[Reflections on the law relating to the protection of persons in biomedical research--concerning trials and experiments not about drugs].

This law, called the law of Huriet, was initially meant to control clinical trials of new medications and to protect "normal volunteers". It has been extended to all trials and all human experimentation, including those undertaken as a last resort and those used for research. It also concerns all new interventions or techniques in which experimentation is included in the therapeutic act, and which are the origin of real progress, day after day, in all manual activities. The example of interventional neuroradiology allows us to understand the consequences/risk of this law on the progress of this technique. Because of the lack of structure defining the acquisition of scientific knowledge in this field, this law will not be able to be applied, and the penalties proposed for not applying the law will result in many law suits.

France↗
PubMed1990

[Intravenous cholangiography is not indicated before cholecystectomy for uncomplicated lithiasis].

The purpose of this prospective study was to assess the usefulness of intravenous cholangiograms before elective cholecystectomy for lithiasis. The accuracy of preoperative intravenous cholangiography to detect choledocolithiasis was compared with that of routine operative cholangiography. All patients had preoperative intravenous cholangiography provided that they did not have known common bile duct gallstones or a previous history of adverse reaction to iodine. As well, patients presenting with cholestasis, cholecystitis or cholangitis were excluded. A choledocotomy was performed when the operative cholangiography disclosed choledocolithiasis; the preoperative intravenous cholangiograms were shown to the surgeon only after the operation. One hundred patients were selected among 206 consecutive operations for biliary lithiasis. A choledocolithiasis was detected in 3 preoperative and in 9 operative cholangiographies. Twelve choledocotomies were performed: one or more stones (1 to 12) were found in 9 patients; operative cholangiography was accurate in all these cases whereas preoperative cholangiography was accurate in only 2 (sensitivity = 22 percent). We conclude that preoperative cholangiography is useless before elective cholecystectomy for lithiasis and is unreliable to select patients in which operative cholangiography could be omitted.

Cholangiography↗
PubMed1989

[Criteria for brain death: cessation of cerebral circulation demonstrated by Doppler ultrasonography of the carotid arteries].

If human death is defined by brain death, its diagnosis needs medicolegal criteria based on clinical examination and EEG. However, this evaluation could be difficult because technical or physiological limitations might impair the interpretation, especially after barbiturates and/or hypothermia. Since brain death is characterized by an intracranial circulatory arrest, methods assessing this phenomenon are warranted. Among these methods, conventional or isotopic cerebral angiography appears the most promising, but it cannot be easily performed everywhere. Because superficial blood flow in arteries is now accurately measured by the pulsed Döppler technique, this prompted us to test the specificity and sensitivity of common carotid blood flow data for brain death diagnosis. Two series of age-matched patients (36 yrs in mean) were studied. Series 1 (n = 28) was used to define the discriminant parameters between 14 severe coma patients and 14 brain-dead patients diagnosed by the classical criteria. Then these parameters were prospectively tested in a blind manner on a second series of 28 patients suffering from severe coma. The parameters allowing us to classify patients as brain dead or not with a 100% specificity and sensitivity were: end diastolic blood flow (QED in ml/min), end diastolic blood flow velocity (VED), and cerebral metabolic index (CMI = QED x AV D 02). The most powerful discriminant parameter was QED, allowing a strictly non-invasive diagnosis of brain death.

Adult↗
PubMed1988

Primary gastric peripheral T-cell malignant lymphoma with helper/inducer phenotype. First case report with a complete histological ultrastructural and immunochemical study.

Primary gastrointestinal T-cell malignant lymphomas (T-ML) are very rare. In this case report we describe a primary gastric tumor with local lymph node involvement. On the basis of histologic, immunohistochemical, and electron microscopic studies, the authors classified this tumor as a pleomorphic T-ML, large cell variant with peripheral helper/inducer T-cell phenotype (Leu1/CD5+, Leu4/CD3+, Leu5/CD2+, Leu9/CD7+, and Leu3/CD4+). The extreme pleomorphism of lymphoma cells, the numerous giant cells, and the presence of tumor nodules with two or three concentric layers were the three striking morphologic features of our case. Tumor cells showed an inconstant but true positive staining with anti-LeuM1/CD15 and LeuM3/CD14 antibodies. Vimentin positivity could be related to the presence of intermediate filaments at ultrastructural level. Neuron-specific enolase reactivity was a peculiar but unexplained feature. Furthermore, the positivity of the surface markers Ki-1/CD30, anti-Tac/CD25 and HLA-DR, and the nuclear marker Ki-67 suggested an activation state and a high proliferative activity of the tumor cells. This study emphasizes the usefulness of combined pathologic methods in order to rule other diagnoses such as undifferentiated carcinoma, malignant melanoma, malignant histiocytosis, B-cell lymphoma and interdigitating reticulum cells sarcoma, in view of an extremely polymorph tumor proliferation. This is apparently the first completely documented case report of a primary gastric pleomorphic T-ML of peripheral T-cell origin.

Antigens, Neoplasm↗
PubMed1987

[Chlamydia trachomatis perityphlitis, an anatomo-clinical entity? Study of 3 cases].

The authors describe three cases of perityphlitis secondary to Chlamydia trachomatis infection and revealed at laparotomy. Clinically, the symptoms invariably mimicked acute appendicitis. The pathogen was identified by a direct immunofluorescent assay with specific monoclonal antibodies (Microtrak). Prompt cure was achieved by doxycycline therapy. Thus, peroperatively, the discovery of an isolated perityphlitis with a normal appendix should raise the possibility of a C. trachomatis infection, even if there is no salpingitis.

Adult↗