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Vincent Maunoury

Publications and source records attributed to Vincent Maunoury.

16 recordsLinked to original sources
PubMed2006

Using white light during photodynamic therapy: visualization only or treatment?

BACKGROUND: Photodynamic therapy (PDT) involves selective uptake and retention of a photosensitizer in a tumor, followed by irradiation with light (usually a 630 nm diode laser), initiating tumor necrosis through formation of oxidized products or singlet oxygen. Successful PDT of early cancers of the esophagus and of Barrett's esophagus with severe dysplasia has been reported. However, side effects (edema, stricture, etc.) and treatment failure have been observed. This study aims to evaluate the possible photodynamic effect induced by illumination from the endoscope on the PDT effect, since a photon emitted to see the lesion can potentially be a photon to treat it! MATERIALS AND METHODS: Two fiber endoscopes (Olympus GIFPQ20 and Pentax FG34X) and one videoendoscope (Olympus GIFQ140) were evaluated. Output power, irradiance and emission spectrum were measured. Using the molar extinction coefficient of Photofrin and optical coefficients of the esophagus, the relative photodynamic reaction yield, determined as a function of depth, was compared with that obtained with a 630 nm diode laser. RESULTS: The irradiance at 1 and 2 cm was, respectively, 18.4 and 4.6 mW/cm (Pentax FG34X), 10.6 and 2.65 mW/cm (Olympus GIFPQ20), and 2.7 and 3.2 mW/cm (Olympus GIFQ140). The highest irradiance could lead to a relative photodynamic reaction yield at the surface of the esophagus similar to (Olympus GIFPQ20) or greater than (Pentax FG34X) that obtained using a diode laser alone. CONCLUSIONS: Our results could explain side effects sometimes observed when performing PDT. 'Endoscopic' illumination, however, could also represent an interesting alternative to the 630 nm diode laser. When using white light, superficial efficacy of PDT could be reinforced and transmural necrosis leading to perforation or stenoses reduced, since there is less red light in depth compared with a diode laser.

Absorption↗
PubMed2004

Impact of Small Bowel Exploration Using Video-Capsule Endoscopy in the Management of Acute Gastrointestinal Graft-versus-Host Disease.

BACKGROUND: The purpose of this study was to evaluate the impact of the global diagnostic approach on the outcome of patients suspected of having acute (a) gastrointestinal (GI) graft-versus-host disease (GVHD). METHODS: Ten consecutive patients with suspected aGI-GVHD were prospectively explored with an exhaustive approach including video-capsule endoscopy (VCE). Images observed with VCE were compared with results obtained with other GI investigations including duodenal biopsies. RESULTS.: Five patients had a normal VCE examination: four were successfully treated symptomatically, but one died as a result of toxoplasmosis. VCE disclosed aGI-GVHD lesions in all five remaining patients, and two of the five were considered normal by upper GI endoscopy. All of these patients experienced improvement in their GI symptoms within 2 weeks of adjustments to their immunosuppressive treatment. CONCLUSIONS: This approach has enhanced the authors' ability to adapt immunosuppressive treatments in patients suffering from suspected aGI-GVHD. Further investigation of the apparently high negative predictive value of VCE will be of great interest, particularly with a view to avoiding unnecessary immunosuppressive treatment.

Acute Disease↗
PubMed2004

Development and validation of a new, simplified endoscopic activity score for Crohn's disease: the SES-CD.

BACKGROUND: Healing of mucosal lesions appears to offer significant benefit and is an important end point in clinical trials of treatment for Crohn's disease. The only validated endoscopic activity score at present is the Crohn's Disease Endoscopic Index of Severity, which is complicated and time consuming and, hence, is unsuitable for routine use. The aim of this study was to develop and to prospectively validate a simpler endoscopic score of disease activity, the Simple Endoscopic Score for Crohn's Disease. METHODS: Selected endoscopic parameters (ulcer size, ulcerated and affected surfaces, stenosis) were scored from 0 to 3. Reproducibility for scoring of these parameters was evaluated through 71 examinations in which the endoscopist was paired with an observer. The simplest score (Simple Endoscopic Score for Crohn's Disease) that was highly correlated with both the Crohn's Disease Endoscopic Index of Severity and Crohn's Disease Activity Index was derived for 70 patients and then was prospectively validated in 121 different patients with Crohn's disease. RESULTS: The interobserver agreement for all selected endoscopic variables was excellent (kappa coefficient 0.791-1.000). Based on multiple linear regression, the Simple Endoscopic Score for Crohn's Disease resulted in the sum of the scores for ulcer size, ulcerated surface, affected surface, and luminal narrowing. In the validation phase of the study, a strong correlation was demonstrated for the Simple Endoscopic Score for Crohn's Disease with Crohn's Disease Endoscopic Index of Severity (r = 0.920). In addition, the Simple Endoscopic Score for Crohn's Disease was correlated to clinical parameters and serum C-reactive protein level. CONCLUSIONS: Simple Endoscopic Score for Crohn's Disease is a simple, reproducible, and easy-to-use endoscopic scoring system for Crohn's disease.

Adult↗
PubMed2002

[Value of endoscopic ultrasonography and somatostatin receptor scintigraphy in the preoperative localization of insulinomas and gastrinomas. Experience of 54 cases].

AIM: The classic morphological techniques for the localization of insulinomas and gastrinomas are of limited value. Endoscopic ultrasonography and somatostatin receptor scintigraphy have shown high sensitivity for the detection of gastroenteropancreatic endocrine tumors. The aim of the study was to evaluate the sensitivity of endoscopic ultrasonography and that of somatostatin receptor scintigraphy in the localization of insulinomas and gastrinomas. PATIENTS AND METHODS: This retrospective study concerned 54 patients with insulinoma (n=29) or gastrinoma (n=26) operated on between March 1991 and March 2000 and who had at least one among the two tested examinations. Forty-two patients had scintigraphy (17 with insulinoma, 25 with gastrinoma), 47 had endoscopic ultrasonography (28 with insulinoma, 17 with gastrinoma). One of the ten patients with MEN 1 had both tumors. All diagnosis were confirmed by histologic examination. RESULTS: The sensitivity of scintigraphy for the localization of insulinomas was 47%. There was one false positive. Sensitivity of endoscopic ultrasonography for insulinomas was 85%. The sensitivity of scintigraphy in the detection of gastrinomas was 65% for the tumors in the duodenopancreatic area, 20% for the tumors in the pancreatic tail and 71% for metastasis. The sensitivity of endoscopic ultrasonography was 46% for duodenal tumors, 75% for pancreatic tumors and 57% for lymph node metastasis. The combination of both localization studies increased sensitivity to 94%. CONCLUSION: Endoscopic ultrasonography and somatostatin receptor scintigraphy are the gold standard for localization of gastrinomas. Association of both examinations increases the sensitivity. Scintigraphy for the detection of insulinomas should be performed when endoscopic ultrasonography is negative.

Adolescent↗
PubMedDate not supplied

Prevalence of risk factors of prion-related disease according to the French circular 138 (DGS/DH/5C/DHOS/E2/2001/138) among patients referred for gastrointestinal endoscopy.

AIM OF THE STUDY: To assess the prevalence of risk factors of prion-related disease transmission in a gastrointestinal endoscopy unit. METHODS: Clinical evaluation of the risk of transmission of prion-related diseases using the criteria defined by the French circular 138 in patients referred for digestive endoscopy without anesthesia. RESULTS: 1017 patients were included in this study. According to circular 138, 7 patients (0.68%) were at high risk of transmitting prion-related disease. According to these criteria, a high index of suspicion of prion-related disease was detected in 26 patients (2.55%). Clinical evaluation of risk was not possible for 56 patients (5.51%), due to coma or sedation (38 patients) or communication impairment (18 patients). CONCLUSIONS: Application of circular 138 led us to consider that 2.55% of patients in this study had a high risk of prion-related disease. The circular criteria cannot be assessed in patients with sedation for mechanical ventilation, coma or communication impairment.

Endoscopy, Gastrointestinal↗