Rates of Vascular Occlusion Associated With Using Needles vs Cannulas for Filler Injection

Abstract

IMPORTANCE Soft-tissue augmentation with skin fillers can be delivered with needles or microcannulas, but unwanted vascular occlusions are possible.OBJECTIVE To determine whether filler-associated vascular occlusion events of the face occur more often with injections performed with needles than with microcannulas. DESIGN, SETTING, AND PARTICIPANTSThis retrospective cohort study included a random sample of board-certified dermatologists deemed eligible based on membership in relevant professional societies and attendance at relevant national professional meetings. Participants completed detailed forms in which they could enter deidentified data and volume statistics pertaining to patients undergoing filler procedures in their practices. Data were collected from August 2018 to August 2019.EXPOSURES Injectable fillers approved by the US Food and Drug Administration delivered via needles or microcannulas. MAIN OUTCOMES AND MEASURESThe primary outcome measure was intravascular occlusion. Occlusion events were graded by severity (no sequelae, scar, and ocular injury or blindness).RESULTS A total of 370 dermatologists (mean [SD] years in practice, 22.3 [11.1] years) participated and reported 1.7 million syringes injected. The risk of occlusion with any particular filler type using needle or cannula never exceeded 1 per 5000 syringes injected. Overall, 1 occlusion per 6410 per 1-mL syringe injections was observed with needles and 1 per 40 882 with cannulas (P < .001). Of the 370 participants, 106 (28.6%) reported at least 1 occlusion. Multivariate analysis found that injections with cannula had 77.1% lower odds of occlusion compared with needle injections. Participants injecting fillers for more than 5 years had 70.7% lower odds of occlusion than those who were less experienced. For each additional injection per week, the odds of occlusion decreased by 1%, and 85% of occlusions had no long-term sequelae. Nasolabial folds and lips were most likely to be occluded, with mean severity level of occlusions highest at the glabella. CONCLUSIONS AND RELEVANCEIn this cohort study, filler injections with either needles or cannulas were associated with a very low risk of intravascular occlusion events. Moreover, the vast majority of such events were minor and resolved without scar or other injury. Injections with microcannulas were less often associated with occlusion events than injections with needles. Occlusion risk per syringe appeared decreased after the first few years of clinical practice and was also lower among those who more frequently inject fillers. Whether a needle or cannula is most appropriate for injection may depend on patient factors, anatomic site, and the type of defect being treated.

Infraorbital Hyaluronic Acid Filler: Common Aesthetic Side Effects With Treatment and Prevention Options

“…Inject as much as possible with a cannula to maximize safety 18 and reduce SEs such as bruising. 19 A needle should be reserved for situations when the results would differ such as treating a depression inferior to the malar mound.…”

“…However, a cannula is recommended to prevent placing a bolus of the solution in the dermis, which could cause temporary atrophy and hypopigmentation (if this occurs, saline can be used to flush the area for quicker resolution). 18 , 22 , 23 In addition, while extremely rare and with higher doses, steroid particles can cause vascular occlusion, so the same precautions taken with filler should be used with light force using a cannula and injecting small amounts while moving retrograde. 24-26 Oral steroids can be used in cases when the swelling is affecting the patient’s quality of life and other measures are not effective.…”

“…Using a cannula can help to ensure that steroids are administered under the skin and decrease the likelihood that it is injected into a vessel, especially with larger-gauge cannulae. 18 , 29 An additional option is camouflaging the swelling by adding additional volume in the cheek around it. If there is skin laxity, laser resurfacing reduces the lax area for fluid to accumulate.…”

Serious Adverse Events With Injectable Fillers: Retrospective Analysis of 7,659 Patient Outcomes

“…A recent study found that board-certified dermatologists injecting fillers for more than 5 years had 70.7% lower odds of vascular occlusion compared with those with less experience. 30 However, there is likely significant underreporting of adverse events by providers from different backgrounds and practice settings. This is supported by a recent survey-based study of 306 American Society of Dermatologic Surgery (ASDS) members which determined that injectable filler treatment resulted in the highest number of complications in patients who visited medical spas.…”

Injection techniques for midface volumization using soft tissue hyaluronic acid fillers designed for dynamic facial movement

“…Although both needles and cannulas can be used to volumize the midface, cannulas may be safer and minimize the risk of intravascular complications. 15,27,28 To optimize the volume of product injected into the midface and en-…”