Research Article A study of variations in the origin of facial artery M. Vijayalakshmi1*, Thenmozhi M S2, Karthik Ganesh Mohanraj2, C. Satheesh Kumar2 ABSTRACT Introduction: Anatomical variations are among one of the important aspect seen during dissection of the cadaver. Such variations have been described elaborately in anatomical literature, and many such studies are still being reported for the first time. Among the anatomical variations vascular particularly arterial variations are encountered quite often during dissection. Facial artery is the important artery that gives major blood supply to the face. It is one of the anterior branch of external carotid artery (ECA). Origin of facial artery may be separate from ECA, or as linguofacial trunk, or thyrolinguofacial trunk. Materials and Methods: Facial arteries in 42 hemifaces in 21 cadavers were studied and analyzed in the Department of Anatomy at Madras Medical College, Chennai, and Melmaruvathur Adhiparasakthi Institute of Medical Sciences, Melmaruvathur. During dissection, the origin of the facial artery is noted and photographed clearly for further analysis. Results: Separate origin of facial artery from ECA was found in 29 out of 42 (69%), common linguofacial trunk was observed in 13 out of 42 (31%), bilateral linguofacial trunk was observed in 5 out of 21 (24%), unilaterally in 3 out of 21 (14%), high origin of facial artery in 1 out of 42 (2%), and hypoplastic or rudimentary facial artery in 1 out of 42 (2%). All the structural variations were photographed for representation. Conclusion: Vascular variations are one of the most important studies on anatomical variations. Such studies and reports throw light on the vascular patterns found in different individuals for surgeons. Thereby, it creates a detailed knowledge about the vascular alterations and alarm about the situation during surgery. The knowledge of these variations is necessary for the surgeons operating on the face during conditions in raising vasculocutaneous flap. KEY WORDS: Anatomical variations, External carotid artery, Facial artery, Vascular surgeon, Vasculocutaneous flaps INTRODUCTION artery, and (iii) hypoplastic facial artery. Knowledge of these variations is necessary for the maxillofacial Facial artery is the second anterior branch from surgeon who raises vasculocutaneous flaps in external carotid artery (ECA) in carotid triangle of the corrective, reconstructive, and cosmetic surgeries. neck. It arises at the level of greater cornu of hyoid bone. It courses forward and upward to reach the MATERIALS AND METHODS medial side of the ramus of mandible where it is related to the medial Pterygoid.[1] Then, it hooks downward, Forty-two hemifaces in 21 cadavers were dissected grooving the posterior edge of the submandibular conventionally at the Department of Anatomy in gland and reaches the inferior margin of the mandible Madras Medical College, Chennai, and Melmaruvathur at an anteroinferior angle of masseter. Here, it hooks Adhiparasakthi Institute of Medical Sciences and around the mandibular margin to reach the face.[2] Research, Tamil Nadu, India, during the past 5 years. Two full-term fetuses and two clinical cases were also Facial artery is the artery of the face derived from the reviewed. During dissection, the origin of the facial first arch. Variations in the origin and the branches of artery is noted and photographed clearly for further the facial artery occur during embryonic period, and it analysis. is described by Gray, Hollinshed (1954).[3,4] The usual variations of facial artery are (i) common faciolingual (unilateral and bilateral), (ii) high origin of facial RESULTS The anatomical variations in the origin of the facial Access this article online artery were categorized as follows: i. Separate origin of the facial artery from ECA was Website: jprsolutions.info ISSN: 0975-7619 found in 29/42 (69%) hemifaces. Figure 1 1Department of Anatomy, Melmaruvathur Adhiparasakthi Institute of Medical Sciences and Research, Melmaruvathur, Tamil Nadu, India, 2Department of Anatomy, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences, Saveetha University, Chennai, Tamil Nadu, India *Corresponding author: M. Vijayalakshmi, Department of Anatomy, Melmaruvathur Adhiparasakthi Institute of Medical Sciences and Research, Tamilnadu Dr. MGR Medical University, Melmaruvathur, Tamil Nadu, India. E-mail: [email protected] Received on: 21-05-2018; Revised on: 26-06-2018; Accepted on: 30-07-2018 2400 Drug Invention Today | Vol 10 • Issue 12 • 2018 M. Vijayalakshmi, et al. ii. Common linguofacial trunk was observed in 2%. The branches in the face were observed to be of very 13/42 (31%) [Figure 2]. narrow caliber in this specimen. The submental branch iii. Bilateral linguofacial trunk was observed in was the largest among them. Bergman reports such 5/21 (24%) cadavers. Unilaterally in 3/21 (14%) occurring, who says the facial artery instead of ending cadavers as an angular artery, may end as submental, labial, or iv. High origin of facial artery 1/42 (2%) [Figures 3 alar branch [Figure 5]. All the observed variations were and 4]. photographed and represented in Figures 6-9. v. Hypoplastic or rudimentary facial artery 1/42 (2%) [Figure 5]. DISCUSSION In this study, the following observation was made. Development of the facial artery: Facial artery Normal separate origin of facial artery from ECA was development occurs in three phases. During initial found in 69% of the hemifaces dissected in the study phase, at 31/2 weeks the visceral arches serve to carry [Figure 1]. Common linguofacial trunk was observed in blood from heart to the rest of the embryo. In the 31%, of the hemifaces dissected. Of these, it was seen second phase by 6 weeks, first two arches lose their bilaterally in 23% and unilaterally in 14.5% of the heads connection with the heart. The first aortic arch vessel dissected [Figure 2]. High origin of facial artery-facial essentially replaces the dorsal end of the second arch artery arising from the ECA above the level of margin artery (hyoid artery). This, adjacent to the internal of mandible was observed in 2%. In this, the facial and carotid artery (ICA) from dorsal aorta persists as the lingual branches were arising just one above the other, stapedial artery virtually supplying the entire facial and it appeared as though they were arising from a region. In the third phase, ECA arises from the aortic common trunk. Grant (1943) observed such origin of the sac close to the ventral end of the third aortic arch. facial artery from ECA [Figures 3 and 4]. Rudimentary The proximal portion of the third aortic arch artery or hypoplastic facial artery was observed in this study in Figure 3: Facial artery - high origin. 1 – External carotid Figure 1: Facial artery – separate origin. 1 – Facial artery, artery, 2 – superior thyroid artery, 3 – lingual artery, 4 – facial 2 – ascending palatine artery, 3 – submental artery artery, 5 – ascending palatine artery, 6 – submental artery Figure 2: Common linguo facial trunk. 1 – External carotid Figure 4: High origin of facial artery – common linguo artery, 2 – common linguo facial trunk, 3 – lingual artery, facial trunk. 1 – External carotid artery, 2 – common linguo 4 – facial artery, 5 – facial vein facial trunk, 3 – lingual artery, 4 and 5 – facial artery Drug Invention Today | Vol 10 • Issue 12 • 2018 2401 M. Vijayalakshmi, et al. adjacent to the ICA grows forward and upward and ECA poses a week point and gives rise to anomalies fuses with the stapedial artery by the 9th week. This of the face due to hemorrhage. becomes the ultimate supply for most of the face. Normal separate origin of facial artery from ECA was Variations occur due to ablation of cardiac neural found in 69% of the hemifaces dissected, in the study crest cells which lead to changes in the embryonic showed above. This was described by Gray et al., but aortic arch vessels. They may be absent, too small, no statistical data were available.[3] Uflacker reports too large, or aberrant in their connection or loss of about the angiographic approach to find out the origin bilateral symmetry. By 4 mm stage, the first and and branches of a facial artery [Figure 6].[5] second arch regresses, the third arch appears, and the blood supply is by the ventral pharyngeal artery, which Common linguofacial trunk was observed in 31%, of originates in the aortic sac and terminates by dividing the hemifaces dissected. Of these, it was seen bilaterally into the mandibular and maxillary artery. Stapedial in 23% of unilaterally in 14.5% of the heads dissected. artery anastomose with the cranial end of the ventral Gray described the same but no statistical data are [3] pharyngeal artery and annexes its terminal distribution. available. Grant observed common faciolingual trunk [1] Hence, fully developed stapedial artery will have in only 20% of 211 specimens he dissected. In the maxillary, mandibular, and supraorbital branches present study, it is a higher incidence, i.e., 31%. Side corresponding to the branches of fifth cranial nerve. to side variation (right to left side) has not been quoted by any scientist. The same as single-sided linguofacial Later on, ECA from the base of the 3rd arch incorporates trunk was described by Kubota, Matsumoto et al., and with the stem of the ventral pharyngeal artery, and its Zumar et al.[6-8] also recorded common linguofacial trunk maxillary branch communicates with the common in their study, occurring unilaterally. Iwai et al. reported trunk of origin of maxillary and mandibular branches common thyrolinguo facial trunk arising 1.6 mm below of the stapedial artery. Fusion between stapedial and the carotid bifurcation on the left side [Figure 7].[9] High origin of facial artery-facial artery arising from the ECA above the level of margin of mandible was Figure 5: Rudimentary facial artery. 1 – Prominent mental artery, 2 – facial artery Figure 7: The percentage of common linguofacial trunk Figure 6: The mode of origin of facial artery from external carotid artery – present study Figure 8: The percentage of high origin of facial artery 2402 Drug Invention Today | Vol 10 • Issue 12 • 2018 M.