The buttonhole method goes back to I beleive the 1960s or 70s when in a ccommunist country they were running out of needles and had to reuse them and they became blunted. The doctor figured out to go to buttonholes to be able to cannulate with blunt needles and the rest is history. What I think we need is info on what type of patients would do best on each technique, including co-morbidities, age, sex, location of fistula, length and size of fistula and technique used. That would be so helpful . There are clearly patients that each technique is more appropriate for . So far no one has really looked at all those factors. Perhaps Stuart Mott will answer some of these questions.