Open AccessRetinal mean transit time determined with an impulse‐response analysis from video fluorescein angiograms
Author(s) -
Sperber G. O.,
Alm A.
Publication year - 1997
Publication title -
acta ophthalmologica scandinavica
Language(s) - English
Resource type - Journals
eISSN - 1600-0420
pISSN - 1395-3907
DOI - 10.1111/j.1600-0420.1997.tb00144.x
Subject(s) - mean transit time , medicine , retinal , ophthalmology , bolus (digestion) , digital image analysis , mtt assay , impulse (physics) , nuclear medicine , biomedical engineering , surgery , cardiology , perfusion , chemistry , computer vision , biochemistry , physics , quantum mechanics , perfusion scanning , computer science , cell
. Purpose : To evaluate a new technique for determing the Mean Transit Time (MTT) of retinal circulation, based on an impulse‐response analysis. The results obtained were compared to those obtained with a conventional method based on semilogarithmic extrapolation. Methods : 128 frames at a rate of 5 frames per second were digitized from video fluorescein angiograms and processed with a specially designed image analysis system. The MTT was determined from 25 curve pairs from 12 eyes in 8 young, healthy volunteers by the conventional technique (MTT SLOPE ) and by our newly developed Impulse‐Response analysis (MTT IR ). Results : MTT SLOPE and MTT IR calculated for the 25 curve pairs were 3.54 ± 1.00 and 2.67 ± 0.88 seconds, respectively (Mean ± SD). There was a good correlation between the two techniques (r 2 = 0.81, p<0.001). Unlike MTT SLOPE MTT IR could be calculated also from curves with a badly defined bolus. Conclusion : We conclude that MTT iR ‐analysis of the retinal circulation may be used for clinical studies on retinal blood flow from angiograms obtained in patients.