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Steffen Rickes

Publications and source records attributed to Steffen Rickes.

27 records · Page 2Linked to original sources
PubMed2004

Evaluation of criteria for the activity of Crohn's disease by power Doppler sonography.

BACKGROUND/AIM: In recent years, power Doppler sonography has been proposed as a method to assess disease activity in patients with Crohn's disease. The aim of this prospective study was to evaluate diagnostic criteria for power Doppler sonography by blinded comparison with ileocolonoscopy. METHODS: Twenty-two patients with confirmed Crohn's disease were prospectively investigated with B-mode and power Doppler sonography (HDI 5000, Philips Ultrasound) as well as ileocolonoscopy. Sonography was performed within 3 days before endoscopy. All procedures were performed by experienced examiners who were blinded to the clinical data and other results. Defined ultrasound parameters (bowel wall thickness, vascularization pattern) were used to determine a sonographic score of the activity. The degree of activity was scored from 1 (none) to 4 (high) by both ultrasound and ileocolonoscopy (pattern, extent of typical lesions). For each patient all segments of the colon and the terminal ileum were evaluated by both ultrasound and endoscopy. The weighted kappa test was used (StatXact software) for statistical analysis. RESULTS: In total, 126 bowel segments were evaluated by both ultrasound and endoscopy. The study showed a high concordance of power Doppler sonography and ileocolonoscopy (weighted kappa by region: sigmoid colon: 0.81; transverse colon: 0.78; ascending colon: 0.75; cecum: 0.84; terminal ileum: 0.82). Highest concordance was found in the descending colon (weighted kappa: 0.91; 95% CI: 0.83-0.98). CONCLUSIONS: Combination of B-mode and power Doppler sonography has a high accuracy in the determination of disease activity in Crohn's disease when compared to ileocolonoscopy. The diagnostic criteria established in this study can be useful for the evaluation of inflammatory bowel diseases by ultrasound.

Adolescent↗
PubMed2004

Evaluation of diagnostic criteria for liver metastases of adenocarcinomas and neuroendocrine tumours at conventional ultrasound, unenhanced power Doppler sonography and echo-enhanced ultrasound.

PURPOSE: In order to improve the differential diagnosis between liver metastases of neuroendocrine tumours and adenocarcinomas, criteria for the masses at conventional ultrasound, unenhanced power Doppler sonography and echo-enhanced ultrasound were evaluated. METHODS: Seventy-three patients with histologically proven liver metastases of a neuroendocrine tumour (n = 26) or an adenocarcinoma (n = 47) were investigated by conventional ultrasound as well as unenhanced power Doppler sonography and echo-enhanced ultrasound focusing on specific properties of the lesions. RESULTS: Liver metastases of neuroendocrine tumours and adenocarcinomas showed a different contrast behaviour with echo-enhanced sonography. A hypervascularisation at the arterial and capillary phase were found in 85% of the neuroendocrine metastases, and in 17% of the masses of adenocarcinomas, respectively (p < 0.05). CONCLUSIONS: The successful treatment of liver metastases requires a highly sensitive and specific diagnostic procedure for their differentiation. A hypervascularisation of the lesions during the arterial and capillary phase at echo-enhanced ultrasound may point to a neuroendocrine primary tumour. However, histology is the only standard of reference for the differentiation of liver metastases, and is necessary for optimal therapy.

Adenocarcinoma↗
PubMed2003

[Aneurysm of the superior mesenteric artery--be careful with the diagnosis of a pancreatic tumor].

HISTORY AND CLINICAL FINDINGS: A 42-year-old woman was admitted with blood pressure crisis. She complained of frontal headache. On clinical examination, a stenotic noise was found localized to the epigastrium. Some days earlier, a pancreatic "tumor" had been diagnosed sonographically by her general practitioner. INVESTIGATIONS: At B-mode sonography, a sharply delineated lesion at the pancreatic tail was found. With color Doppler sonography, blood flow could be detected within the "mass", which was interpreted as an aneurysm of the superior mesenteric artery. Furthermore, an aneurysmatic gastroduodenal artery was diagnosed. The sonographic findings were confirmed by CT scan, which additionally revealed an aneurysm of a segmental renal artery. COURSE: Given the danger of spontaneous rupture, the aneurysm of the superior mesenteric artery was resected. Under antihypertensive therapy, normal blood pressure values could be achieved, and the patient is symptom-free. CONCLUSION: Color and power Doppler sonography are useful in the differential diagnosis of pancreatic tumors. With these methods, erroneously suspected "tumors", e.g., an aneurysm of a mesenteric artery, can be differentiated from true lesions. Thus, complications of the aneurysm such as spontaneously rupture or intervention-associated bleeding can be prevented.

Adult↗
PubMed2003

Improved diagnosing of small hepatocellular carcinomas by echo-enhanced power Doppler sonography in patients with cirrhosis.

BACKGROUND AND AIMS: Echo-enhanced power Doppler sonography is an increasingly used procedure for the differentiation of liver tumours. The aim of this prospective study was to investigate the accuracy of echo-enhanced power Doppler sonography in comparison with conventional ultrasound and fundamental power Doppler sonography in diagnosing hepatocellular carcinomas and regenerative nodules in patients with cirrhosis. SUBJECTS AND METHODS: Eighty-seven patients with cirrhosis and 90 liver tumours at conventional ultrasound were included in the study, selected from 103 consecutive patients with a mean age of 60 years (range 23-87 years) who presented to our department from January 1998 through January 2002. Sonography was performed by an experienced examiner, who was unaware of the clinical diagnosis. The exact diagnosis was based upon histological evidence from biopsy examination, laboratory results, and/or a follow-up of at least 18 months. RESULTS: There were 65 hepatocellular carcinomas, 21 regenerative nodules, and four metastases in the study group. Only 43% of the carcinomas (mainly nodules > 3 cm in diameter) could be classified correctly by conventional ultrasound or fundamental power Doppler sonography. However, 46% of the malign lesions (mainly nodules < 3 cm in diameter) were not differentiable. All non-differentiable tumours were classified correctly by echo-enhanced power Doppler sonography. The overall sensitivity of echo-enhanced power Doppler sonography with respect to diagnosing hepatocellular carcinoma was 89%; its specificity was 60%. The corresponding values for regenerative nodules were 71% and 100%, respectively. CONCLUSIONS: Only hepatocellular carcinomas greater than 3 cm in size can be diagnosed with a high accuracy by conventional ultrasound or fundamental power Doppler sonography. However, small malignant lesions in cirrhotic livers are often not differentiable with these techniques. With echo-enhanced power Doppler sonography, the differentiation of small hepatocellular carcinomas can be improved. However, histology is the standard of reference.

Adult↗
PubMed2003

Microsatellite alterations in free-circulating serum DNA in patients with ulcerative colitis.

BACKGROUND/AIMS: The aim of this study was to find out whether there is free-circulating DNA in the serum of patients with ulcerative colitis and whether it is possible to establish a panel of genetic alterations which might be useful markers for diagnostic purposes, staging, or follow up. METHODS: A set of 11 microsatellite markers located on different chromosomes were analyzed in a group of 59 patients with ulcerative colitis. Radiolabeled PCR products from serum and white blood cell DNA were analyzed by autoradiography and correlated with the clinical data from these patients. RESULTS: Seven of 59 patients showed one or more microsatellite alteration(s) in their serum DNA. Six patients had an alteration in one marker, and two patients had changes in 4 markers, respectively. There was no correlation between the frequency of microsatellite alterations and the clinical data. CONCLUSION: From the panel of 11 microsatellite markers used for these studies, 6 of them seem to be well suited for the detection of ulcerative colitis-associated alterations in free circulating serum DNA. In order to increase the specificity of this assay, it is necessary to increase the number of patients to be analyzed and to use a different set of markers.

Biomarkers↗