Tissue expander injection dome leakage.

Injection dome leakage was found to be the cause for partial disappearance of the saline solution injected into some tissue expanders. When the injection domes of 22 consecutively removed tissue expanders were checked, we found that the average leakage pressure of these was 32 mmHg, with a range of 8 to 110 mmHg. When the patients were lying on their expanders, the weight of the corresponding body part caused intraluminal pressures of up to 90 mmHg in their expanders. Following removal of the expanders, the total leakage was calculated quantitatively and found to be maximally over 50 percent of the injected volume in some instances. The leakage flow through the injection dome in seven consecutively removed expanders was checked at pressures of 25, 50, and 75 mmHg over 30 minutes and was found to be slow. The possibility of injection dome leakage should be kept in mind, however, as a potential complication under unfavorable conditions. At the same time, we want to emphasize that in most instances tissue expanders function quite well and in predictable ways.