Young-Chun Gil

Variations of the Superficial Brachial Artery in Korean Cadavers

The superficial brachial artery (SBA), a branch of the axillary artery, is one of the most common arterial variations in this area. While it is more vulnerable to accidental arterial injection or injury, it could be useful for the nourishment of a medial arm skin free flap. To analyze the relationship between the SBA of axillary origin and segmental variation of the axillary artery, we dissected 304 arms of Korean cadavers. We found an SBA of axillary origin in 12.2% of cadaveric arms. Unilateral occurrence was detected in 16 cadavers and bilateral in 10. SBAs gave rise to radial and ulnar arteries in the cubital fossa (8.9%), continued in the forearm as the radial artery (2.3%), or ended in the upper arm (1.0%). The SBA ended as ulnar artery was not found in any of the cadavers. The bifurcation of the SBA into the radial and ulnar arteries, presence of an SBA that ends in the upper arm, and the lack of continuation as the ulnar artery are characteristics of SBAs in Korean cadavers.

New Anatomical Insights on the Course and Branching Patterns of the Facial Artery: Clinical Implications of Injectable Treatments to the Nasolabial Fold and Nasojugal Groove

Background: Improper manipulation of injectable treatments to the face can result in disastrous vascular complications. The aim of the present study was to elucidate the detoured course of the facial artery and to provide detailed metric data regarding facial artery location with a view to helping physicians avoid iatrogenic vascular accidents during injectable treatments. Methods: Sixty specimens from 35 embalmed cadavers (24 male and 11 female cadavers; mean age, 70.0 years) and one fresh male cadaver (age, 62 years) were used for this study. Results: In 56 cases (93.3 percent), the branches of the facial artery were observed at the vicinity of the nasolabial fold. The facial artery was located 3.2 ± 4.5 mm (mean ± SD) lateral to the ala of the nose and 13.5 ± 5.4 mm lateral to the oral commissure. It crossed the nasolabial fold in 33.9 percent of cases, and ascended within 5 mm of the nasolabial fold in 42.9 percent. The facial artery and detoured branches were found in 18 cases (30.0 percent). In the cases with detoured branches, the facial artery turned medially over the infraorbital area at 39.2 ± 5.8 mm lateral to the facial midsagittal line and 35.2 ± 8.2 mm inferior to the plane connecting the medial epicanthi of both sides. The nasojugal portion of the detoured branch traveled along the inferior border of the orbicularis oculi and then ascended toward the forehead, forming the angular artery. Conclusion: This detailed vascular anatomy of the facial artery will promote safe clinical manipulations during injectable treatments to the nasolabial fold and nasojugal groove.

Topographical anatomy of the suprascapular nerve and vessels at the suprascapular notch

Suprascapular nerve entrapment caused by the superior transverse scapular ligament (STSL) causes pain, and limitation of motion in the shoulder. To relieve these symptoms, suprascapular nerve decompression is performed through the resection of STSL. To describe and classify the topographic anatomy of the suprascapular notch, 103 cadaveric shoulders were dissected. The mean length and width of STSLs were 11.2 and 3.4 mm, respectively. The bony bridges replacing STSL in four shoulders were 8.2 mm long and 3.5 mm wide on average. The suprascapular nerve always ran through the notch under the STSL. All shoulders had a single suprascapular artery, while multiple suprascapular veins appeared in 21.3%. The arrangement of the suprascapular vessels was classified into three types: in Type I (59.4%), all suprascapular vessels ran over the STSL; in Type II (29.7%), the vessels ran over and under the STSL simultaneously; in Type III (10.9%), all vessels ran under the STSL. In 48.9% of cadavers, these types were bilaterally matched. The omohyoid muscle originated distantly from the STSL in 38.0%, was adjacent to it in 44.0%, and was partially over the STSL in 18.0%. The number of suprascapular vessels running under the STSL was positively correlated with the size of the STSL and the middle diameter of the suprascapular notch. Age was inversely correlated with the length of STSL. The STSL was wider in males than in females. This study provides details of the structural variations in the region of the suprascapular notch. Clin. Anat. 25:359–365, 2012.

The anatomical origin and course of the angular artery regarding its clinical implications.

BACKGROUND The purposes of this study were to determine the morphological features and conceptualize the anatomical definition of the angular artery (AA) as an aid to practical operations in the clinical field. MATERIALS AND METHODS Thirty-one hemifaces from 17 Korean cadavers and 26 hemifaces from 13 Thai cadavers were dissected. RESULTS The topography of the AA was classified into 4 types according to its course: Type I (persistent pattern), in which the AA traverses the lateral side of the nose (11%); Type II (detouring pattern), in which the AA traverses the cheek and tear trough area (18%); Type III (alternative pattern), in which the AA traverses the medial canthal area through a branch of the ophthalmic artery (22.8%); and Type IV (latent pattern), in which the AA is absent (26.3%). CONCLUSION The findings of this study will contribute toward improved outcomes for cosmetic surgery involving the injection of facial filler by enhancing the understanding of AA anatomy.

Topographical anatomy of the transverse facial artery

The transverse facial artery (TFA) is found in the lateral face and supplies the parotid gland and duct, facial nerve, facial muscles, and skin. To better understand the cutaneous vascularization of the lateral face and to better characterize the topography and other anatomical features of the TFA, microsurgical dissection was performed in 44 cadavers. The number of TFAs present ranged from one to three, and a single TFA was most common (70.5%). The TFA originated from the superficial temporal artery at or above the level of crossing by the temporofacial trunk of the facial nerve in the parotid gland (57.6%). The TFA divided into superior and inferior trunks in the gland, and continued as emerging branch. The superior emerging branch emerged from the gland superior to the parotid duct and divided into many branches. It supplied the malar area, crossed the parotid duct, terminated as perforator, vasa nervorum, or artery to the parotid duct or muscle. The inferior trunk in 72.5% continued as emerging branch instead of terminating in the gland. TFAs were classified into four types; the most common type was Type A in which the superior and inferior emerging branches and the duct‐crossing branch were present. The mean number of perforators to the superficial cutaneous layer was 1.9. Most perforators extended from the superior emerging branches (77.9%). The most common perforating site was below the duct on the anterior third of the masseter muscle. In two cases, the TFA formed an anastomosis with the facial artery. Clin. Anat. 23:168–178, 2010.

Anatomy of thoracic splanchnic nerves for surgical resection

Thoracic splanchnic nerves conduct pain sensation from the abdominal organs around the celiac ganglion. Splanchnicectomy is the procedure used mainly for the control of intractable visceral pain. Forty‐six human posterior thoracic walls were dissected. The formation pattern, course, and incidence of communication of the thoracic splanchnic nerves were investigated. The greater splanchnic nerves (GSNs) were formed by nerve branches from the T4–T11 thoracic sympathetic ganglia and the most common type was formed by T5–T9 (21.7%). The uppermost branches originated from T4–T9 while the lowermost branches emanated from the T7–T11. Two to seven ganglia contributed to the GSNs. In 54.3% of the specimens, at least one ganglion in the GSN‐tributary ganglionic array did not branch to the GSN. The lesser splanchnic nerves (LSNs) were formed by the nerve branches of the T8–T12 thoracic sympathetic ganglia and the most common type was formed by T10 and T11 (32.6%). One to five ganglia were involved in the LSNs. The least splanchnic nerves (lSNs) were composed of branches from the T10–L1 thoracic sympathetic ganglia and the most common type was composed of nerve branches from T11 and T12 or from T12 only (each 30.4%). One to three ganglia were involved in the lSNs. In 54.3% of the specimens, interconnection between the GSNs and the LSNs existed, bringing the possible bypass around the transection of the GSNs. The splanchnic nerves that appear in textbooks occurred in a minority of our specimens. We provided expanded anatomical data for splanchnicectomy in this report. Clin. Anat. 21:171–177, 2008.

Novel findings of the anatomy and variations of the axillary vein and its tributaries.

The anatomy and variations of the axillary vein has significant implications in various invasive procedures such as venous access, axillary block, arteriovenous fistula creation, axillary node dissection, breast augmentation, and other surgical procedures involving the axilla. To clarify the anatomy of the axillary vein and its tributaries, 40 cadaveric upper extremities were examined after dissection and were classified into several types according to the courses and terminations of brachial veins. The brachial veins ended separately (Type A; 72.5%) or made a common brachial vein (Type B; 27.5%) to enter the basilic vein or the axillary vein. The basilic vein was absent in 5.0% of the specimens. Duplication of the axillary vein was observed in 17.5% of the specimens and the lateral venous channel running along the lateral wall of the axilla was observed in 40.0% of the specimens. The most common drainage vein of the deep brachial vein was the lateral brachial vein (67.5%). The anterior circumflex humeral vein also emptied into the lateral brachial vein in 67.5% of the specimens. The posterior circumflex humeral vein crossed posterior side of the brachial plexus to join either the axillary vein (45.0%) or subscapular vein (42.5%). Perforation of the lateral root of median nerve by a lateral brachial vein, a common brachial vein, or a venous channel was observed in 15.0% of the specimens. Other venous variations accompanying the variations of the axillary artery or the brachial artery are described herein. The clinical importance of these findings is described in the discussion. Clin. Anat. 25:893–902, 2012.

Intersegmental origin of the axillary artery and accompanying variation in the brachial plexus

The wide anatomical variation of the brachial plexus and the axillary artery has been thoroughly explored in previous studies. However, there has been little information reported on the variation in the relationship between the brachial plexus and the axillary artery. The principal feature of this relationship is the passage of the axillary artery through the loop of the median nerve, which occurs in normal arteries derived from the seventh intersegmental artery. In this study, we analyzed the abnormal position and course of the axillary artery related to the brachial plexus in 607 axillae of 306 cadavers. We found 12 unusual axillary arteries that did not pass through the median loop. Eleven arteries were determined to be ninth intersegmental arteries and one as the sixth intersegmental artery. All ninth intersegmental arteries ran caudally to the brachial plexus. In six cases of this type, abnormal connections interfering with the normal arterial position were observed in the brachial plexus. In another five cases of this type, the lateral and medial cords merged and the axillary artery passed anteromedial to the plexus. The sixth intersegmental axillary artery pierced the musculocutaneous nerve which is from the unified lateral and medial cords. This study discussed the how the anomalous structure of the brachial plexus could involve the deterioration of the course of the axillary artery. Clin. Anat. 22:586–594, 2009.

Topographical anatomy of the radial nerve and its muscular branches related to surface landmarks.

Understanding of the anatomy of the radial nerve and its branches is vital to the treatment of humeral fracture or the restoration of upper extremity function. In this study, we dissected 40 upper extremities from adult cadavers to locate the course of the radial nerve and the origins and insertions of the branches of the radial nerve using surface landmarks. The radial nerve reached and left the radial groove and pierced the lateral intermuscular septum, at the levels of 46.7, 60.5, and 66.8% from the acromion to the transepicondylar line, respectively. Branches to the long head of the triceps brachii originated in the axilla, and branches to the medial and lateral heads originated in the axilla or in the arm. The muscular attachments to the long, medial, and lateral heads were on average 34.0 mm proximal, 16.4 mm distal, and 19.3 mm proximal to the level of inferior end of the deltoid muscle, respectively. The radial nerve innervated 65.0% of the brachialis muscles. Branches to the brachioradialis and those to the extensor carpi radialis longus arose from the radial nerve above the transepicondylar line. Branches to the extensor carpi radialis brevis usually arose from the deep branch of radial nerve (67.5%); however, in some cases, branches to the extensor carpi radialis brevis arose from either the radial nerve (20.0%) or the superficial branch of the radial nerve (12.5%). Using these data, the course of the radial nerve can be estimated by observing the surface of the arm. Clin. Anat. 26:862–869, 2013.

Three-dimensional study of the facial canal using microcomputed tomography for improved anatomical comprehension.

The aims of this study were to determine the various dimensions of the normal facial canal and to identify the spatial relationships between the facial canal and its adjacent structures using microcomputed tomography (micro‐CT) imaging and three‐dimensional (3D) reconstruction. The petrous parts of 54 temporal bones were scanned using micro‐CT with a slice thickness of 35 μm. The serial micro‐CT images were used to reconstruct 3D volumes of the facial canal and the bony labyrinth with the aid of computer software. These volumes were used to measure 31 dimensions of the facial canal and its spatial relationships with adjacent structures. The length of the meatal segment, the tympanic segment, and the mastoid segment were significantly larger in males than in females (p < 0.05). The narrowest portions of the facial canal were immediately lateral to the meatal foramen in the labyrinthine segment and the midpoint of the tympanic segment. The distance between the origin of the canal for the chorda tympani nerve and midpoint of the stylomastoid foramen was 35.3% of the length of the mastoid segment, and the angle between the tympanic segment and the lateral semicircular canal was 16.3°. The angle between the mastoid segment and the canal for the chorda tympani nerve could be classified into two groups: <180° and >180°. These findings represent supplemental data for improving the detailed understanding of the facial canal anatomy. Anat Rec, 297:1808–1816, 2014.