The necessity for technical precision in vascular anastomosis is of vital importance and the principal of anastomotic casts as an aid to surgical training is obviously desirable. There are, however, some aspects of the described methodology that might limit its usefulness.
I have attempted similar studies using epoxy resins, which I found very difficult to handle. Fortunately I discovered a cheap, 'user-friendly' alternative. Dow Corning make a white bath and kitchen seal (silicone rubber) ideal for the purpose. It is sold in syringe-like containers, cures relatively quickly, gives off no heat and is not compromised by moisture. It is possible to pressurize the cast using a small volume ( <0.5 ml) of water at the tip of a needle introduced at some convenient point, connected to a three-way tap, pressure manometer and fluid reservoir. The resulting cast is rubbery and durable. It is not necessary to use any dissolution techniques to remove the tissues from the cast as they can be easily cut away without damaging the cast. Analysis of cross-sectional detail is easy because the silicone rubber can be cut with an ordinary scalpel blade.
I was impressed by the technique described for reading anastomotic contour. I am concerned, however, that the equipment and time involved might not he universally available. It is widely accepted that the anastomotic regions of primary importance are the heel and toe. I suggest, therefore, that measurement at each of these is sufficient to illustrate a trainee's progress. All that is required is to measure the artery in question in two planes; dividing one diameter by the other results in a 'distortion quotient'. Any deviation from 1.0 (a perfect circle) indicates anastomotic distortion.
I have used the above technique to compare the anastomotic distortion incurred by direct expanded polytetrafluoroethylene-artery, Miller collar and Taylor patch anastomoses'.