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The efficacy of roselle (Hibicus sabdariffa Linn.) flower tea as oral negative contrast agent for MRCP study
Vithya Varavithya1, Sith Phongkitkarun, Janjira Jatchavala
1Department of Radiology, Faculty of Medicine, Srinakharinwirot University, Nakhon-Nayok 26120, Thailand.
Objective:
To evaluate the efficacy of roselle flower tea (RFT) administration as oral negative contrast agent for MRCP study.
Material And Method:
Roselle flower tea was prepared by packing 4,000 mg of dry ground roselle flower in a tea bag and soaked with 480 ml of hot distilled water RFT was tested in phantom, volunteer subjects and was studied in patients for MRCP study. Quanlitative analysis was made by evaluation of the conspicuity of biliary system after RFT administration. Quantitative comparison was performed by comparing the contrast-to-noise ratio between each part of the biliary system with stomach and duodenum.
Results:
Roselle flower tea can effectively reduce signal intensity of the stomach and duodenum. There was statistically significant (p < 0.05) improvement in conspicuity of the common bile duct. There was slight improvement of conspicuity of common hepatic duct, ampulla and main pancreatic duct. Contrast-to-noise ratios were all statistically significantly improved. RFT contains 0.6 mg of iron and 1.28 mg of manganese content.
Conclusion:
Roselle flower tea is a very efficient oral negative contrast agent. It is natural, safe, inexpensive and palatable for oral administration.
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