„clinics afford me about 60 squint operations a year, and they are all „followed up till the patients are aged 14. My tenotomies have been „confined to the central tendon and have been followed by an anchor „suture which should have prevented the muscle falling far back, and „yet I have seen children, some of them 8 years after the operation, who „show definite lack of convergence, and not a few divergence. I have „seen eyes remain parallel for as long as a year and then for no apparent „reason diverge to such an extent that re-advancement has been called for.
„Tenotomy being a dangerous operation in that it leaves weekness „behind it, we are left with muscle recession as the only practical way of „dealing with the internal rectus,
„The operation that I have been performing for the past 16 years has „been Worth advancement, mostly with tenotomy, and looking back, I „am far from satisfied with the results obtained. There haven been diver„gencies and lack of converging power, and not a few of the operations „have been complete failures in the reverse sence; the strabismus has not „been cured. Of the first hundred 50 % were perfect, 35 persons improved, „having about 7 degrees of residual convergence. The remainder were „failures."
Den laatsten tijd doet hij dan ook alleen advancement gecombineerd zoo noodig met „musclerecession" !). Op ongeveer 100 aldus geopereerde patiënten had hij zeer weinig mislukkingen. De controle over deze gevallen strekte zich uit over een tijdsverloop van 18 maanden.
') Onder musclerecession verstaat Harrison Butler het naar achteren brengen van de insertie door de pees door te snijden en zoo ver als noodig geacht wordt naar achter aan den bulbus vast te naaien.