Use of handheld ultrasound Doppler to prevent complications from intra-arterial injection of dermal fillers: Clinical experience

Bridging a Century-Old Problem: The Pathophysiology and Molecular Mechanisms of HA Filler-Induced Vascular Occlusion (FIVO)-Implications for Therapeutic Interventions

Biocompatible hyaluronic acid (HA, hyaluronan) gel implants have altered the therapeutic landscape of surgery and medicine, fostering an array of innovative products that include viscosurgical aids, synovial supplements, and drug-eluting nanomaterials. However, it is perhaps the explosive growth in the cosmetic applications of injectable dermal fillers that has captured the brightest spotlight, emerging as the dominant modality in plastic surgery and aesthetic medicine. The popularity surge with which injectable HA fillers have risen to in vogue status has also brought a concomitant increase in the incidence of once-rare iatrogenic vaso-occlusive injuries ranging from disfiguring facial skin necrosis to disabling neuro-ophthalmological sequelae. As our understanding of the pathophysiology of these injuries has evolved, supplemented by more than a century of astute observations, the formulation of novel therapeutic and preventative strategies has permitted the amelioration of this burdensome complication. In this special issue article, we review the relevant mechanisms underlying HA filler-induced vascular occlusion (FIVO), with particular emphasis on the rheo-mechanical aspects of vascular blockade; the thromboembolic potential of HA mixtures; and the tissue-specific ischemic susceptibility of microvascular networks, which leads to underperfusion, hypoxia, and ultimate injury. In addition, recent therapeutic advances and novel considerations on the prevention and management of muco-cutaneous and neuro-ophthalmological complications are examined.

An Anatomical Guide to the Terminal Facial Artery: Lumen Diameter and Associated Anatomy Relevant to Dermatologic Procedures

BACKGROUND

Dermal filler injection in the vicinity of the terminal facial artery (FA) can lead to vascular compromise with devastating consequences, including tissue necrosis, blindness, and stroke.

OBJECTIVE

The purpose of this study was to examine lumen diameter and other anatomical features of the terminal FA relevant to dermal filler injection.

MATERIALS AND METHODS

Eighteen embalmed adult cadavers were dissected along the distribution of the terminal FA. Gross and microscopic measurements were taken at predetermined points in its course.

RESULTS

Mean lumen diameter was largest at the midpoint between the oral commissure and the lateral supra-alar crease (0.81 ± 0.36 mm; point P1) and smallest at the midpoint between the lateral supra-alar crease and the medial canthus (0.43 ± 0.23 mm; point P3). Mean cutaneous depth was deepest at the lateral supra-alar crease (5.06 ± 1.84 mm; point P2) and most superficial at the midpoint between the lateral supra-alar crease and the medial canthus (3.13 ± 2.07 mm; point P3).

CONCLUSION

The large-caliber lumen diameter of the terminal FA creates the potential for intra-arterial injection with commonly used filler needles and blunt-tipped cannulas at all points in its course in the nasolabial fold and midface.