Endoscopic fluorescein flowmetry in the evaluation of gastric and duodenal mucosal blood flow

Fluorescein flowmetry (FF) implies the measurement of a relative capillary blood flow, expressed as an index--that is, the ratio between the maximum fluorescence, obtained during the first circulatory passage of sodium fluorescein (Na-F), and the rise time, defined as the time interval between 10% and 90% of the maximum fluorescence. The aim of this study was to develop FF to be used during endoscopy for the evaluation of ventricular and duodenal mucosal blood flow. FF was applied during gastroduodenoscopy in 38 patients with normal mucosa, as verified by histopathologic examination. The blood flow index did not differ significantly for the mucosa of the fundus, corpus, and antrum. However, when compared with the duodenal mucosa, the blood flow index of the ventricular mucosa was almost twice as high (P less than 0.01). This, in turn, was due to a significantly higher maximum fluorescence in the ventricular mucosa (P less than 0.01), indicating a denser capillary network than in the duodenal mucosa. Since FF is a reliable method, easy to perform and without complications, it is suitable whenever mucosal blood flow warrants measurement during endoscopy.