Publications by authors named "Waleed Ajaj"

Background: The purpose of this pilot study was to assess the diagnostic accuracy of MR colonography (MRC) without bowel cleansing regarding its ability to quantify inflammatory bowel disease (IBD). In addition, patient acceptance was compared with conventional colonoscopy (CC).

Methods: In all, 29 patients with IBD (17 ulcerative colitis; 12 Crohn's disease) were included.

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The aim of the study was to evaluate the utility of dark-lumen MR colonography (MRC) for the assessment of extra-colonic organs. Three hundred seventy-five subjects with suspected colonic disease underwent a complete MRC examination. MRC data were evaluated by two radiologists in a blinded fashion.

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In the last few years virtual colonography using MR imaging has shown a proceeding development regarding detection and quantification of colorectal pathologies. Dark-lumen MR colonography (MRC) has been a leading tool for the diagnosis of the entire colon and their pathologies. This review article describes some of the underlying techniques of MRC concerning data acquisition, the need for intravenously applied paramagnetic contrast agent, as well as indications, results and limitations of MRC for the detection of colorectal pathologies.

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Purpose: To assess the clinical relevance of dark-lumen MR colonography (MRC) for the detection of colorectal lesions using conventional colonoscopy (CC) and histopathologic examinations as reference standard.

Materials And Methods: A total of 72 patients underwent MRC and CC. MRC was performed using a contrast-enhanced high spatial resolution T1 weighted 3D volumetric interpolated breathhold examination (VIBE)-sequence.

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Objective: The purpose of this study was to assess oral contrast agents, volumes of the agents, and time points of data acquisition in regard to small-bowel distention and patient acceptance.

Subjects And Methods: Six healthy volunteers underwent imaging on 16 different days. Four volumes (450, 900, 1,350, and 1,800 mL) of each of the four contrast compounds (0.

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Purpose: To assess colonic anastomoses in patients after surgical treatment by means of MR colonography (MRC) in comparison with conventional colonoscopy (CC).

Materials And Methods: A total of 39 patients who had previously undergone colonic resection and end-to-end-anastomosis were included in the study. MRI was based on a dark-lumen approach.

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MR colonography has been shown to be an appropriate diagnostic tool for the detection of colorectal lesions. The technique is based on the acquisition of T1-weighted sequences after the administration of water enema and the intravenous administration of paramagnetic contrast. This article describes the technical requirements for MR colonoscopy and the procedures of data acquisition and image interpretation.

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To assess dark-lumen magnetic resonance colonography (MRC) for the evaluation of patients with suspected sigmoid diverticulitis. Forty patients with suspected sigmoid diverticulitis underwent MRC within 72 h prior to conventional colonoscopy (CC). A three-dimensional T1-weighted volumetric interpolated breath-hold examination sequence was acquired after an aqueous enema and intravenous administration of gadolinium-based contrast agents.

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The aim of our study was to assess the effect of oral and rectal stool softeners on dark-lumen magnetic resonance (MR) colonography without bowel cleansing. Ten volunteers underwent MR colonography without colonic cleansing. A baseline examination was performed without oral or rectal administration of stool softeners.

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Dark-lumen magnetic resonance colonography has been shown to be an appropriate diagnostic tool for the detection of colorectal pathologies. This review describes the underlying techniques of dark-lumen magnetic resonance colonography concerning data acquisition, image interpretation and diagnostic accuracy for the detection of colorectal pathologies. In addition, techniques to improve patients' acceptance are discussed.

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Purpose: To assess the impact of an additional rectal enema filling in small bowel hydro-MRI in patients with Crohn's disease.

Materials And Methods: A total of 40 patients with known Crohn's disease were analyzed retrospectively: 20 patients only ingested an oral contrast agent (group A), the other 20 subjects obtained an additional rectal water enema (group B). For small bowel distension, a solution containing 0.

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MR colonography (MRC) is an accurate diagnostic tool for the detection of colorectal masses and inflammatory diseases. This article describes the underlying techniques of MRC that concern data acquisition and image interpretation. Indications for MRC are discussed, and technical developments are explained.

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Purpose: To evaluate image subtraction for the detection of colonic pathologies in a dark-lumen MR colonography exam.

Materials And Methods: A total of 20 patients (12 males; 8 females; mean 51.4 years of age) underwent MR colonography after standard cleansing and a rectal water enema on a 1.

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To assess the effect of the osmolarity for small bowel distension in MRI, ten volunteers ingested at two separate occasions negative oral contrast agents with different quantity and osmolarity: (1) a water solution combined with 2.0% sorbitol and 0.2% locus bean gum (LBG) with a quantity of 1500 ml and an osmolarity of 148 mOsmol/l, (2) a water solution combined with 2.

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Objective: High diagnostic accuracy, emerging whole-body concepts, and lack of side effects combine to render MRI a natural candidate for screening purposes. The aim of this study was to evaluate the technical feasibility of a comprehensive multiorgan-targeting MRI examination and determine the frequency of findings in subjects without a history of serious disease.

Subjects And Methods: The study group was composed of 331 subjects.

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Purpose: The purpose of this study was to compare a dark-lumen magnetic resonance colonography (MRC) approach with a True FISP-based bright-lumen technique concerning presence of artifacts and the detection rate of colorectal pathologies.

Materials And Methods: Thirty-seven patients with suspected colorectal lesions were included in this trial. The colon was filled with 2500 mL of tap water.

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The purpose of this study, which was approved by the institutional review board, was to assess the differentiation of individuals with from those without mesenteric ischemia. All subjects provided written informed consent. Six healthy volunteers and six patients with documented chronic mesenteric ischemia underwent magnetic resonance (MR) imaging with and without oral caloric stimulation.

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Purpose: To assess dark-lumen magnetic resonance (MR) colonography for the evaluation of colonic segments in patients in whom conventional colonoscopy could not be completed.

Materials And Methods: Institutional review board approval and written informed consent were obtained. Within 24 hours of incomplete conventional colonoscopy, 37 patients (22 women, 15 men; age range, 25-63 years) underwent MR colonography.

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The aim of this study was to assess a venous compression technique that is performed with contrast material-enhanced peripheral magnetic resonance (MR) angiography to reduce venous enhancement. Healthy volunteers, as well as patients with correlating digital subtraction angiographic (DSA) findings, were examined. Venous compression was accomplished by placing a cuff at the midfemoral level unilaterally.

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Purpose: To optimize the dose of a hydro solution containing 2.5% mannitol and 0.2% locust bean gum (LBG) for small bowel MRI in terms of bowel distension and patient acceptance.

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Purpose: To examine the magnetic resonance (MR) properties of different foods and their effect on the colonic stool signal to potentially support fecal tagging strategies for dark lumen MR colonography (MRC).

Materials And Methods: T1 relaxation times of 120 different foods (partially diluted with sufficient water) were determined by use of a multi-flip-angle two-dimensional gradient echo (GRE) sequence and correlated to the foods' signal in a three-dimensional GRE volumetric interpolated breath-hold examination (VIBE) sequence. Different dilutions of six foods were examined.

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MR elastography (MRE) has been shown to be capable of non-invasively measuring tissue elasticity even in deep-lying regions. Although limited studies have already been published examining in vivo muscle elasticity, it is still not clear over what range the in vivo elasticity values vary. The present study intends to produce further information by examining four different skeletal muscles in a group of 12 healthy volunteers in the age range of 27-38 years.

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MRI of the small bowel is a new method for the assessment of inflammatory bowel diseases. However, inflammatory bowel disease can affect both the small and large bowel. Therefore, our goal was to assess the feasibility of displaying the small bowel and colon simultaneously by MR imaging.

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Purpose: To determine the practicality of MRI using a new real-time sequence for the assessment of gastric motion, and quantify the effects of motility-modifying substances.

Materials And Methods: Six healthy volunteers ingested 400 mL of a high-calorie liquid nutrient. Two-dimensional real-time TrueFISP sequences were acquired for up to 30 minutes following the ingestion.

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