Clinical implications of the arterial supplies and their anastomotic territories in the nasolabial region for avoiding arterial complications during soft tissue filler injection

Abstract

Background The nasolabial fold is one of the most concerning aging property in the middle face region. This fold initially appears when people are coming age‐wise to their 20s. To correct this fold, the aesthetic nonsurgical procedure, known as filler injection, has been popularly and increasingly performed. However, the arterial complications occurring as a consequence of nasolabial fold filler injection have been continually reported in a recent year. Therefore, the objective of this study was to investigate the arterial location related to nasolabial fold filler injection sites and their anastomotic pathways. Methods Thirty hemi‐faces of 15 Thai embalmed cadavers were performed by dissection method. The nasolabial folds (NLF) were used as the anatomical landmarks: at the inferior margin of NLF (NLF1), at the level of the mid philtral horizontal line of NLF (NLF2), and at the inferior alar level of NLF (NLF3). Additionally, the 5 cadavers were underwent the modified Sihler's staining procedure to investigate the arterial anastomoses. Results The main artery nearby of NLF1 and NLF2 was the facial artery. The facial artery located inferior and medial to NLF1 (Type I, 7 of 25 cases); moreover, the mean distance was 3.53 ± 2.11 mm along the X‐axis and 3.53 ± 1.75 mm along the Y‐axis. The facial artery located medial (Type V, 12 of 22 cases) to NLF2 and the distance was 4.93 ± 1.53 mm along the X‐axis. For the NLF3, there were several accurate arteries including the facial artery (10 of 30 cases), the infraorbital artery (9 of 30 cases) and the lateral nasal artery (10 of 30 cases). The anastomosis of the nasolabial arteries was served both as the connection of external‐external carotid system and the connection of internal‐external carotid system. The communication between the facial artery and the transverse facial artery was found in all specimen. Similarly, the communication between the facial artery and the infraorbital artery was seen in all cases. Finally, the anastomosis between the dorsal nasal artery and the lateral nasal artery was found in 5 of 10 (50%) cases. Conclusion At the lower part of NLF, the facial artery must be concerned. The filler injection should not over approximately 1.5 mm medial to NLF1 and 1 mm inferior to NLF1. For the NLF2, the safe injection point should less than 2.5 mm in the medial direction. In order to prevent injury of the facial artery and the infraorbital artery, the injection tools must not be exceeded 2 mm lateral to NLF3, while the injection less than 2 mm medial to NLF3 is the harmless point for the lateral nasal artery. The possibility of blindness might be caused by the anastomosis between the lateral nasal artery and the dorsal nasal artery. Support or Funding Information The 100th Anniversary Chulalongkorn University Fund for Doctoral Scholarship from the Graduate School, Chulalongkorn University Overseas Academic Presentation Scholarship for Graduate Students from the Graduate School, Chulalongkorn University This abstract is from the Experimental Biology 2018 Me...

Facial vascular danger zones for filler injections

“…Anastomoses of the nasolabial arteries served to connect both the externalexternal and internal-external carotid systems (Figure 7). 23 In the NLF, any injections in the anastomosis of the angular artery, and lateral nasal artery can lead to retrograde embolism resulting in visual loss. 24 Another possible complication is alar necrosis after injection into the alar triangle, which often results in disfiguring shape of the nose and necessity of subsequent surgical repair.…”

“…Anastomoses of the nasolabial arteries served to connect both the external‐external and internal‐external carotid systems (Figure 7). 23 …”

Efficacy and Safety of Resilient Hyaluronic Acid Fillers Injected with a Cannula: A Randomized, Evaluator-Blinded, Split-Face Controlled Study

“…Although NLF injections are very common in clinical practice, the area presents anatomical specificities making the procedure technically complex. 4–6 Briefly, the NLF represents the anatomical border between the cheek, with its generous layer of subcutaneous fat, and the lip, where the skin directly adheres to the orbicularis oris muscle with very little intervening fat. 6 Musculodermal insertions of the lip elevator muscles underneath the NLF bring further complexity to the tissue layers’ arrangement.…”

Precise extratemporal pattern and intramuscular distribution of the facial nerve

“…Additionally, the mean length and diameter of the posterior auricular nerve were 27.11 ±5.02 mm and 0.85 ±0.20 mm, respectively 197 . Importantly, the anatomical landmark of the posterior auricular nerve was used to identify the FN for decreasing iatrogenic injury 198 .…”