Filler Migration Versus Technique
Migration of Injectables
Richard O. Gregory, MD
Migration of injectable material in tissue is a subject that frequently is discussed whenever an unanticipated result happens.Although there is undoubtedly migration into surrounding tissue this is sometimes given as a reason for the bad result when in fact the problem is more technique related.Add to this the influence of swelling, massage, positioning after treatment and it becomes a complex situation.
It is obvious that there are many factors which might influence migration or distribution of an injectable.Is the injected material a liquid or solid (thick gel)? Is it warm or cold? Is it intentionally inject into one location or fanned out as many techniques describe?What is the tissue into which the injection is done – muscle, fat, fibrous such as tendon or fascia, etc.?Are there tissue planes at the injection site which “channel” the material?An experienced injector will know these various factors and although not entirely predictable many times not only can problems be avoided, but these influencing factors can be used to enhance the result.
Although the analogy may stretch the facts a bit, consider kitty litter.Solid material is generally held in place by the litter and any associated fluid is absorbed whereas only fluid tends to diffuse into the litter for a distance before being absorbed.The same principle applies to the injected material – Is it liquid like Botox or a solid (gel) such as Juvederm?Continuing the analysis you shouldconsider the purpose of the injection = Do you want it to diffuse and be absorbed where most biochemical reactions occur such as Botox or do you want it to stay in place such as Voluma to give lift (g’ as it is called)?An interesting observation from the University of Michigan seems to indicate that distending collagen with an injected material causes the production of more collagen in response. The same principle applies to Sculptra (L-lactic acid) in which the crystalline nature of the product probably further enhances the collagen build up. Thus one can presume that not only does filler material provide volume to tissue but also may increase the collagen content of the tissue thus lending “permanence”.
Probably a larger factor than migration is technique, considering vast variation in the skill and experience of injectors.It requires little more than a piece of paper hanging on the wall for a person to be called an injector.The “wall paper” does not reflect the training, experience and even the caring of the person doing the injection.Which is the real point of this discussion - the injected material may not be material to the result as much as the caring, the training and the experience of the injector.