A study conducted by the Department of Dermatology at the Feinberg School of Medicine, Northwestern University, has suggested that cannulas are less likely to cause a vascular occlusion than needles when injecting filler.
The study evaluated injection practices, injection volumes and prior intravascular occlusion events of 370 dermatologists, with a total of 1.7 million injections.
Results showed that one occlusion occurred per 6,410 injections via needles, compared to one occlusion per 40,882 injections with cannulas.
The study also indicated that there was no significant association between filler type and vascular occlusion in cannulas. However, in needles, poly-L-lactic acid was shown to have 72.5% lower odds of occlusion than hyaluronic acid.
The authors of the study commented, “Cannulas appear to be less likely to be associated with occlusions than needles. But based on the data analysed, it appears both types of instruments are safe, with occlusions occurring in, on average, fewer than one per 5,000 syringes when injections are performed by dermatologists.”