Search

The elevator muscles of the upper lip are the levator labii superioris alaeque nasi, levator labii superioris, and zygomaticus minor muscles, which function by means of their insertions into the skin of the upper lip. However, many textbooks and journal articles state that no muscle fibers are present on the orbicularis oris muscle in the upper lip. The authors attempted to determine whether there is a superficial muscle layer in addition to the orbicularis oris muscle in the upper lip.The authors performed gross dissections of 10 formalin-fixed cadavers and applied micro-computed tomography to six formalin-fixed cadavers. The fine dissection of the upper lip was performed in a layer-by-layer manner that elucidated its muscle layers. The entire layer of the upper lip was separated and pretreated with phosphotungstic acid for micro-computed tomography. The samples used for micro-computed tomography were repurposed for use in histologic analysis. An ultrasonography study was also performed.The presence of a muscle layer on the orbicularis oris muscle was confirmed in all samples. The elevator muscle fibers of the upper lip formed a layer by combining with connective tissue. Micro-computed tomography indicated lower terminal insertions of the elevator muscles throughout the upper lip. All parts of the upper lip skin were inserted into the orbicularis oris muscle. The histologic findings were similar to those of micro-computed tomography.The authors' findings could be used to improve aesthetic and surgical procedures performed on the upper lip, such as correction of gummy smile and transverse upper labial crease, or postresection reconstruction of the upper lip.

Background Retrobulbar filler injection has recently been considered an ideal method for orbital volume enhancement due to its nontoxic, easily reversible, and noninvasive characteristics. This study determined the arterial distribution in the orbit with the aim of defining a safety zone for retrobulbar filler injections used to enhance the orbital volume. Methods Twenty-seven orbits of 24 formalin-embalmed cadavers were dissected. The orbital arteries were identified after removal of the eyeball, extraocular muscles, and connective tissues. The course of each orbital artery was then recorded in each specimen, and all of the courses were then superimposed to determine the arterial distribution in the orbit. Results The superimposition of lined images based on the orbital vasculature of each specimen revealed that the arterial density was highest in the superonasal region and lowest in the inferotemporal region. In particular, orbital arteries were scarce at 8 o'clock and 4 o'clock in the right and left orbits, respectively, and an artery-free zone was demonstrated in the outer part of those directions. Conclusions When performing a transcutaneous retrobulbar injection of filler for orbital volume enhancement, the relative safety zone could be considered to be located at 8 o'clock and 4 o'clock in the right and left orbits, respectively. The detailed topographic information about the arterial distribution in the orbit, provided by the present study, may help oculofacial surgeons to avoid injury to major vessels and decrease the risk of retrobulbar hemorrhage and vision-threatening complications.

Summary Background The deep temporal fascia (DTF) is known to separate into two layers that descend to attach to the zygomatic arch. When surgeons reduce an isolated fracture of the zygomatic arch through a temporal approach, the temporal incision site needs to be superior to the split line of the DTF. Materials and Methods Sixty-seven hemifacial cadavers were investigated after removing the skin, subcutaneous tissue, and superficial temporal fascia. The superficial layer of the DTF was exposed. We cut the superficial layer along the line along, which it adhered to the deep layer inseparably. The heights of the split line of the DTF from the superior border of the zygomatic arch and from the top of the helix were measured at three points: at the jugale, zygion, and 3 cm from the tragus. Results In all cases there were thick identifiable deep layers of the DTF. The mean heights of the split line of the DTF from the superior border of the zygomatic arch were 49.8, 46.7, and 42.6 mm at the jugale, zygion, and 3 cm from the tragus, respectively; the corresponding mean heights of the split line from the top of the helix were 19.1, 15.6, and 11.4 mm. Conclusions Knowledge of the mean height of the split line of the DTF will be helpful for surgeons to determine the temporal incision site for ensuring the safe reduction of a zygomatic arch fracture.

Background Vision loss caused by retrograde occlusion of the central retinal artery is a serious complication of cosmetic filler injections. Salvage methods that involve applying hyaluronidases in the retrobulbar space to degrade filler materials have been proposed recently for rescuing the retinal circulation in an ophthalmic emergency. Methods Sixty-six eyeballs and orbital contents were extracted from formalin-embalmed cadavers and dissected carefully to examine the topographic relationship of the central retinal artery and optic nerve. To observe the three-dimensional course of a central retinal artery that invaginates into the optic nerve, serial sections reconstructed at 100-μm intervals using software were visualized in 11 specimens. Results The central retinal artery ramified from the ophthalmic artery and entered the optic nerve inferiorly at 8.7 ± 1.7 mm (mean ± SD) from the posterior margin of the eyeball. The intraneural course of a central retinal artery changed acutely between the periorbital environment of the fibrous optic nerve sheath, intermediate subarachnoid spaces, and center of the optic nerve stroma. Conclusion When applying a retrobulbar approach for central retinal artery reperfusion with hyaluronidases, the reliable access route is suggested to be at a depth of 3.0 to 3.5 cm from the border of the inferolateral orbital rim, based on consideration of the entry point of the central retinal artery into the optic nerve.

The present study is to identify primarily the morphological characteristics in the growth proportion of the head and face for young Korean (8~24 years) and compare the magnitude of growth changes to the sex-related differences. Total 1,255 were divided into 3 age groups: childhood (8~10 years), adolescence (14~16 years), and young adult (20~24 years). The anthropometric assessments were performed with 11 landmarks on the head and facial dimensions. The standardized frontal and lateral head and face photographs were analyzed the craniofacial growth proportions and morphological features for the comparison of both sexes. The noteworthy differences of anthropometric measurements between sexes with growing were noted on the lower head height (22.6%, 17.8%), midface height (22.0%, 19.6%), lower face height (23.5%, 14.7%), and face length (21.1%, 14.9%), face breadth (14.8%, 11.3%) of males and females, respectively. Whereas the upper head height (7.9%, 6.0%) and upper face height (4.2%, 0%, respectively) were less growing features. The most remarkable changes are the dimension of midface height and lower face height in both sexes. The present study could demonstrate a fundamental example to elucidate the sex-related dimensional differences for the analysis of the growth proportion of both sexes in Koreans.

The iliacus muscle is a large, flat, triangle-shaped muscle located in the iliac fossa. This muscle forms part of the iliopsoas muscle complex. Although anatomical variations of iliacus muscles are rare, some variations are clinically important due to the possible coexistence of an unusual course of the femoral nerve. The femoral nerve is the largest branch of the lumbar plexus and supplies the muscles and skin in the anterior aspect of the thigh. We encountered a case of a single aberrant slip of the iliacus muscle piercing the femoral nerve in the left iliac fossa of a male cadaver aged 97 years. The potential clinical importance of this variant iliacus muscle accompanied by a femoral nerve split would be femoral neuropathy and possible consequent alterations of sensation in the anterior and medial aspects of the thigh or motor deficit of the quadriceps muscle.

Vision loss and skin necrosis caused by an accidental intraarterial embolism or vascular compression are rare but devastating complications when injecting filler materials into the face.The external and internal diameters and wall thicknesses of the facial artery and its branches were measured from 41 formalin-embalmed cadavers after removing connective tissues attached to the arterial wall.The diameter and thickness of the facial artery exhibited significant interregional differences. The external and internal diameters of the facial artery were 1.9 ± 0.4 and 1.2 ± 0.3 mm (mean ± SD), respectively, at the inferior border of the mandible; 1.7 ± 0.3 and 1.2 ± 0.3 mm in the vicinity of the inferior labial artery; 1.5 ± 0.3 and 1.0 ± 0.3 mm at the mouth corner; 1.4 ± 0.3 and 0.9 ± 0.2 mm in the vicinity of the superior labial artery; and 1.1 ± 0.2 and 0.7 ± 0.2 mm in the vicinity of the lateral nasal artery. The external and internal diameters at the proximal parts of the inferior labial artery, superior labial artery, and lateral nasal artery were 1.0 ± 0.3 and 0.6 ± 0.2 mm, 0.9 ± 0.3 and 0.6 ± 0.2 mm, and 0.8 ± 0.2 and 0.5 ± 0.2 mm, respectively.Morphometric examinations of the facial artery under stereomicroscope observation as performed in the present study are expected to be more accurate than direct measurements obtained during cadaveric dissection or conventional histologic evaluations.

The Frankfurt line is the most frequently and widely used reference line in cephalometric analysis, but has shortcomings including the difficulty of landmark identification. This study investigated using the superior border of the zygomatic arch as a new external bony landmark, including measuring the angle between the new reference line and the Frankfurt line. Facial computed tomography scans were obtained from 170 patients (100 males and 70 females) hospitalized at Konkuk University Chungju Hospital. After three-dimensional reconstruction, the locations of the porion and the inferior orbital rim and the superior border of the zygomatic arch were identified twice by two observers using software. A horizontal line parallel to the superior border of the zygomatic arch was established. The angle between the Frankfurt line and new reference line was then measured on each side. There was no significant intraobserver or interobserver bias. The angle between the Frankfurt line and the superior border of the zygomatic arch was 4.5° ± 2.5° (mean ± SD), and it was somewhat larger in females than males, but the difference was not statistically significant. This study demonstrated the good reproducibility of the location of the superior border of the zygomatic arch and found that the angle between the new reference line and the Frankfurt line is relatively constant. The superior border of the zygomatic arch therefore has potential as an alternative reference line to the Frankfurt line in specific clinical applications and anthropological studies, since it is a more accessible bony landmark on the external skull.

Summary Background Volumetric rejuvenation of the dorsum of the hand with fat grafting or injectable fillers has increased in popularity in recent years. It has become widely accepted that the dorsum of the hand contains three fatty laminae: superficial, intermediate, and deep laminae. The dorsal venous plexus and dorsal cutaneous nerves are known to reside in the dorsal intermediate lamina. However, the superficial vein and cutaneous nerve might not be located in the same layer of subcutaneous tissue, as is the case in other body regions. Materials and Methods Eight hands were dissected in a layer-by-layer fashion from the skin to the extensor tendons. In another 13 hands from among 21 investigated cadavers, samples from the dorsum of the hand were harvested and stained using trichrome stains for histologic analysis. B-mode ultrasound was also performed for identifying structures of the dorsum of the hand. Results Anatomic dissection and histologic analysis of the dorsum of the hand revealed the presence of an unknown fascia in addition to the three known fascial layers. The additional fascia was located in the dorsal intermediate lamina and separated it into two compartments: one containing the dorsal venous plexus superficially and the other containing the dorsal cutaneous nerves deeply. Ultrasound showed corresponding structures including three hyperechoic fascial layers, three hypoechoic laminae, and additional hyperechoic fascia in dorsal intermediate lamina. Conclusions Accurate anatomic knowledge of the dorsum of the hand will help practitioners determine the optimal and safe locations for performing fat grafting and injecting dermal fillers.

Background Deep circumflex iliac artery osteocutaneous flap transfer has frequently been applied to large defects in the maxillary and mandible regions, but the use rate has decreased gradually because of the complicated anatomy of the deep circumflex iliac artery. This study investigated the comprehensive anatomy of the deep circumflex iliac artery in relation to flap surgery with the aim of providing navigational guidelines for safe deep circumflex iliac artery harvesting. Methods Sixty-two sides of the hemi-abdominal wall were dissected in fixed Korean cadavers. Several dimensions of the deep circumflex iliac artery and its positional relationships with surgical landmarks were measured, and the patterns of the arterial supply and anastomosis were identified. Results The mean distance between the anterior superior iliac spine and the lateral border of the femoral artery was 57.5 mm. The deep circumflex iliac artery generally originated almost at the same level as the inguinal ligament, and its highest level was 14.8 mm superior to that ligament. Emerging points of the ascending branch were observed both medial and lateral to the anterior superior iliac spine, but no transverse branch pierced the transversus abdominis muscle medial to the anterior superior iliac spine. Conclusions The incision line for safe deep circumflex iliac artery harvesting was parallel and 2 cm superior to the inguinal ligament and 6 cm from the anterior superior iliac spine. This position of the safe incision line can be easily determined using the thumb. Sex differences in the incidence of the deep circumflex iliac artery originating above or below the inguinal ligament will be another useful guide for easily detecting the deep circumflex iliac artery.

PURPOSE The aim of the study was to elucidate the positional relationship of the ethmoidal foramens (EFs) with reference to the nasion to facilitate prediction of the exact location of EFs, the optic canal (OC), and the frontoethmoidal suture (FS), and thereby avoid complications during complex surgery involving the medial wall of the orbit. MATERIALS AND METHODS One hundred two intact orbits of 57 embalmed cadavers were dissected in this observational anatomic study. Nasion' (N') was defined as the intersection point of the medial orbit margin with the horizontal line through the nasion, and this was used as a reference point. N'-OC was defined as the straight line joining N' and OC. The locations of the anterior ethmoidal foramen (AEF), posterior ethmoidal foramen (PEF), and OC were determined with reference to N'. The vertical distances from N'-OC to EFs and to FS were also determined. RESULTS The N'-AEF, AEF-PEF, and PEF-OC distances were 18.4, 15.3, and 8.3 mm, respectively. Vertically, AEF and PEF were situated at 0.2 mm below and 0.4 mm above N'-OC, respectively. At the same reference points, N'-OC was situated at 0.4 and 0.6 mm above FS, respectively. CONCLUSIONS N', AEF, PEF, and OC were considered to be situated on the same straight line, and N'-OC could be regarded as coinciding with FS. This means that N' is an easily identifiable and reliable landmark for identifying EFs, OC, and FS. Our navigational parameters with reference to N' will help surgeons to enhance the safety of orbital surgery.

Background Blocking the supraorbital nerve (SON) and supratrochlear nerve (STN) by injecting anesthetic distal to the surgical site has the advantage in upper eyelid surgery that avoids obscuring the surgical landmarks and compromising the levator function. Objective To identify the emerging points of the SON and STN in the supraorbital margin with reference to the lacrimal caruncle. Methods Forty-nine orbits from 27 embalmed Korean cadavers were dissected. The lacrimal caruncle and facial midline were used as landmarks. The emerging points of the SON and STN in the supraorbital margin were determined. Results The emerging points of the SON and STN were, respectively, located at 3.0 mm lateral and 3.3 mm medial to the vertical line through the apex of the lacrimal caruncle along the supraorbital margin. The horizontal distances from the facial midline to the emerging points of the SON and STN were 22.8 and 15.2 mm, respectively. Conclusion The optimum sites for achieving SON and STN block are, respectively, located approximately 3 mm lateral and 3 mm medial to the vertical line through the apex of lacrimal caruncle along the supraorbital margin. This knowledge will help the surgeon achieve an easy and accurate approach for regional nerve block.

PURPOSE This study evaluated midfacial asymmetry using an alternative method that involved comparing bilateral patterns of the zygomaticomaxillary prominence in a young adult population. MATERIALS AND METHODS Three-dimensional reconstructed images based on computed tomography scans of 100 Koreans (mean age, 24.7 years) were evaluated with reference to lines spaced at 30° intervals and radiating from the center of an interporion line in a superior view. The surface inclination of the zygomaticomaxillary region was quantified on the same reference lines using a 3-dimensional ruler. RESULTS The 30°-interval line (at the level of the zygomaticotemporal suture) was longer on the left side than the right side in both males and females, whereas the left 60°-interval line (at the level of the zygomaticofrontal suture) was longer in females. Comparing the surface protrusion revealed that the zygomaticomaxillary region was more prognathic and inflated on the left side. CONCLUSION Functional deviations are considered to be causes of asymmetric craniofacial growth. Postnatal growth allometry across the circummaxillary sutures as elucidated by this study could be useful information in craniofacial surgery.

Purpose To identify the location of the inferior oblique muscle (IOM) origin with reference to the lacrimal caruncle in order to facilitate safer oculofacial surgery by preventing morbidity associated with IOM injury. Methods Thirty-seven intact orbits of 20 embalmed Asian cadavers were dissected. The location of the medial border of the IOM origin was determined with respect to the apex of the lacrimal caruncle. In addition, the size of the IOM origin and the anteroposterior distance from the inferior orbital rim to the anterior border of the IOM origin were measured. Results The IOM origin was located at a mean distance of 1.2 mm lateral and 11.2 mm inferior to the apex of the lacrimal caruncle. In half of the orbits, the IOM origin was situated just on the vertical line through the apex of the lacrimal caruncle. The mean length and width of the IOM origin were 4.3 and 2.7 mm, respectively. The mean anteroposterior distance from the inferior orbital rim to the IOM origin was 1.9 mm. Conclusions The lacrimal caruncle is easily identifiable and a reliable external landmark for prediction of the IOM origin. The IOM origin is located approximately where the vertical line through the apex of the lacrimal caruncle intersects the inferior orbital rim. The findings of this anatomical study of the exact location of the IOM origin can help to improve the safety of oculofacial surgery.

The aim of this study was to clarify the definition of the anterior wall of the ulnar tunnel and to reveal the topographical characteristics of the various components of the ulnar tunnel.Twenty-two forearms from 11 embalmed cadavers (7 males, 4 females; mean age, 67.8 years) were carefully dissected.In all cases, the anterior wall of the ulnar tunnel comprised the hypothenar fascia, which originated from the tendon of the flexor carpi ulnaris muscle. The palmar carpal ligament, the distal extent of the antebrachial fascia, was located deep to the anterior wall and formed only the anterior boundary of the proximal hiatus of the ulnar tunnel. The hypothenar fascia was attached to the flexor retinaculum at 15.2 mm lateral to the pisiform bone. However, the palmar carpal ligament was attached to the flexor retinaculum just lateral to the ulnar artery; the distance between the attachment of the palmar carpal ligament and the pisiform bone was 8.7 mm. Anatomical variations potentially associated with ulnar nerve compression were observed. The accessory abductor digiti minimi muscle and the fibrous band crossing the ulnar nerve in the ulnar tunnel were found in 27 and 23 % of forearms, respectively.A more detailed description of the anterior wall of the ulnar tunnel than was previously available is presented herein, and topographic and metric data regarding each structure of the tunnel are reported.

Background The aims of the present study were to clarify the topographic relationships between various structures in the lateral midface and to provide important anatomical information pertinent to face lifting or treatment of damage to the midface structure. Methods Thirty-two fixed cadavers were dissected (23 males and 9 females; mean age, 66.8 years) and 55 sides of midface were used. The transverse facial artery (TFA), zygomatic branch (Zb) and buccal branch (Bb) of the facial nerve, and the parotid duct (PD) were identified. The structures of the lateral midface were measured relative to the zygion and tragion. The vertical average distances from the zygion to each structure increased in the following order: ZB of the facial nerve, TFA, first Bb of the facial nerve, and PD. The horizontal average distance from the tragion to the point of emergence from anterior border of the parotid gland was also measured. Results The TFA was the closest and the third Bb of the facial nerve was the farthest away. The angles between the horizontal line and ZB of the facial nerve, TFA, PD, and first Bb of the facial nerve were +10.4, -2.3, -18.5, and -27.1 degrees, respectively. Conclusions These results may be used to establish the precise locations and the courses of the important midface structures, and represent valuable data that may help to prevent complications during surgery for face lifting and reconstruction of the facial nerve and PD.

BACKGROUNDS The aims of the present study were to determine the exact level of separation of the upper lateral cartilage from the septal cartilage, and to classify the patterns of connection between the upper lateral cartilage and the lower lateral cartilage. METHODS We dissected and photographed 60 sides of noses; 18 specimens were sectioned and stained with Masson's trichrome. RESULTS The mean length of the connection between the upper lateral cartilage and septal cartilage was 16.1 mm. The mean level for separation of the upper lateral cartilage was 7.5 mm from the nasal bone. The pattern of connection between the upper lateral cartilage and lower lateral cartilage could be classified into five types: disconnection, end-to-end, overlap, scroll, and reverse scroll. CONCLUSIONS The results of the present study will be helpful for surgical procedures such as nasal hump reduction and nasal cartilage work and also provide information for the anthropometric study of the nose.

These cortical and trabecular bones maintain general bone structure. Bone mineral density (BMD) changes according to increasing age, sex, and teeth loss. From previous studies, the evaluation of BMD changes depended on conventional radiographic analysis. This study investigated the trabecular bone ratio (TBR) in maxillary bone samples based on data obtained by micro-computed tomography and estimated variations in BMD according to age, sex, and tooth loss. Thirty-eight specimens were scanned with micro-computed tomography and reconstructed three-dimensionally. Sections were made parallel to the axis of each tooth, and the TBR was measured. Data were statistically analyzed with 1-way analysis of variance and paired t-tests (α=0.05). The TBR differed significantly (P

Purpose To investigate the incidence of digital nerve loop penetration by digital arteries (neural loops) in cadaver palms and to classify these neural loops according to their topography and morphology. Methods In total, 121 palms (from 57 right and 64 left hands) were dissected from 70 preserved cadavers (50 male and 20 female; mean age 66.1 y). Results Of the 121 palms, 98 had neural loops; 184 cases of neural loop were observed in total. The neural loops could be classified into 4 topographical types, according to their position relative to the digital arteries: ulnar (in which the ulnar proper palmar digital nerve of the finger is penetrated), radial (in which the radial proper palmar digital nerve of the finger is penetrated), common (in which the common palmar digital nerve of the finger is penetrated), and bridge (in which the neural loop is formed by connecting the ulnar and radial proper palmar digital nerves). The neural loops were also classified morphologically according to their size: form A (≥10 mm), form B (4.0–9.9 mm), and form C (≤3.9 mm). The mean lengths in these groups were 16.1, 7.2, and 3.0 mm, respectively, and the overall mean length of all neural loops was 10.8 mm. Conclusions It was confirmed that neural loops are a common occurrence in humans; hence, it is surprising that it is a little-known variation in the palm.

Objective The objective of this study was to provide the safest and most efficient site for injection of botulinum toxin type A into the masseter muscle. Study design This study was performed on 40 hemifaces from cadavers. The surface of the masseter was compartmentalized into areas I to VIII. Areas I, III, V, and VII were assigned to represent the upper 4 compartments from the posterior aspect of each muscle, and areas II, IV, VI, and VIII were assigned to represent the lower 4 compartments. Results The parotid gland usually covered compartments I and II, and the marginal mandibular branch of the facial nerve was located a mean of 7.4 mm above the inferior mandibular margin. The parotid duct was usually located above the reference line connecting the tragus and the cheilion. Conclusion The center of compartment VI is the safest and most efficient injection site for botulinum toxin type A into the masseter muscle.

Cortical bone and trabecular portion play important roles in maintaining the general structure of bone. It has been reported that a decrease in bone mineral density is related with increasing age, sex, and teeth loss. However, most of the studies were done with conventional radiographic analysis. In addition, data from Korean population are rare. The aim of this study was to analyze trabecular pattern of the mandible using micro-computed tomography. Thirty-nine specimens of the mandible were prepared. Specimens were scanned with micro-computed tomography and reconstructed three-dimensionally. Sections were made parallel to the axis of each tooth. Trabecular bone ratio (TBR) was measured. Data were statistically analyzed with 1-way analysis of variance (alpha = 0.05). There was a statistically significant difference of TBR between dentate and edentulous mandibles in the molar region. Trabecular bone ratio of edentulous mandible in males was greater than that in females. Trabecular bone ratio of dentate mandibles reduced regularly with increasing age, whereas that of edentulous mandibles did not. It could be concluded that there were statistically significant differences in TBR according to presence of tooth, sex, and increasing age on specific areas.

The present study involved a detailed investigation of 3 cases of bifid rib, focusing on anatomical features, and classified them into 2 types. The bifid ribs were in the right fourth rib of all 3 male cadavers. The upper intercostal spaces of the fourth bifid rib were considerably narrowed, whereas the lower intercostal spaces were widened. Although the size and shape of the bifid space between the upper and lower divisions of the bifid rib were different, the intercostal muscles were present in the bifid space in all cases. The third anterior intercostal artery from the internal thoracic artery supplied the bifid space in all cases. In 2 cases, the fourth intercostal nerve ran along the inferior margin of the fourth bifid rib and innervated the muscles of the bifid space. In the third case, there was another branch from the third intercostal nerve supplying the muscles of the bifid space as well as the fourth intercostal nerve. The bifid ribs are associated with other diseases or develop accidentally or sporadically. Knowledge of this malformation is needed for the differential diagnosis with other diseases, such as a chest wall tumor or costal fracture.

To compare the distribution of extramuscular nerve branches with their intramuscular ramifications in the triceps surae muscle, thus providing anatomical substantiation for the topography of muscle resection and botulinum toxin injections.Dissection and modified Sihler's staining of 18 whole-mount human cadaveric specimens.The distance between the areas with the highest extramuscular branch density and the area of densest intramuscular arborization in gastrocnemius and soleus muscles is approximately 10% of the calf length. This finding should be taken into consideration during nerve blocking and botulinum toxin injections for the treatment of spasticity. Intramuscular nerve arborization patterns make it possible to outline neuromuscular segments in the gastrocnemius and soleus muscles.Surgical or therapeutic interventions in areas of high extramuscular and intramuscular nerve density can increase the efficacy and safety of botulinum toxin injections and neurotomy. Intramuscular nerve branching patterns should be taken into consideration during triceps surae resection.

The labiomandibular fold (LMF) is the area of the face that extends from the mouth corner to the mandibular border, and its prominence tends to increase with age. The LMF can be formed by the medial or lateral border of the depressor anguli oris (DAO). The aim of this study was to demonstrate the topographical anatomy between the DAO and mental foramen, thereby providing critical information for the safest and most effective site at which to inject botulinum toxin type A (BTX-A). Thirty-four hemifaces from Korean adult cadavers were dissected. The maximum width between the medial borders of the bilateral DAO, parallel to the intercheilion horizontal line, was 59.9 +/- 4.6 (mean +/- SD) mm below the lower lip. The minimum width between the medial borders of the attachment of bilateral DAO was 29.7 +/- 4.8 mm at the mandibular border. The mental foramen was located in the middle third from the cheilion to the mandibular border in 28 cases (90.3%), and it was mostly confined within the DAO muscle coverage in 21 cases (67.7%). The buccal branch of the facial nerve entered through the middle third of the lateral border of DAO and then distributed. Concomitantly, the marginal mandibular branch of the facial nerve entered through the lower third of the lateral border of DAO in 17 cases (60.7%). These results represent additional reference data for identifying the position of the mental foramen on the facial skin, and will be useful for providing criteria for the most effective site for injecting BTX-A when treating the LMF.

Background: The aim of this study was to clarify the arrangement of the zygomaticus major muscle by means of topographic examination, and to evaluate the anatomical variations in the insertion of the zygomaticus major at the perioral region. Methods: After a detailed dissection in the modiolar region, the insertion area of the zygomaticus major was observed in 70 embalmed cadavers. Results: At the perioral region of the dissected specimens, the anatomical aspects of the muscular arrangement and attachment of the zygomaticus major muscle were classified into four categories. In type I, the superficial muscle band of the zygomaticus major is blended and interlaced with the levator anguli oris, whereas the fibers of the deep muscle band blend into the buccinator, passing deeper to the levator anguli oris; this was the situation most commonly encountered (54.3 percent). It was found that the insertion of the zygomaticus major was divided into superficial and deep bands (types I and IV) [42 cases (60 percent)] and into three layers of superficial, middle, and deep fibers (type II) [17 cases (24.3 percent)]. The others were cases where the zygomaticus major was inserted deep into the levator anguli oris as a single muscle band (type III) [11 cases (15.7 percent)]. Conclusion: The arrangement and insertion patterns of the zygomaticus major in this study are expected to provide critical information for surgical planning for the procedure of facial reanimation surgery.

Purpose Organs and structures develop symmetrically, but various degrees of asymmetry can also develop because of the effects of function and disease. The human face is often asymmetrical, but faces can be perceived as beautiful even if they are asymmetrical. The purpose of the present study was to investigate horizontal angular asymmetry of the face. Materials and Methods The angle between the horizontal line through the bilateral exocanthions and the line though the bilateral mouth corners of the face was measured on standardized frontal facial photographs of 1,282 volunteers (18 to 29 years of age; 761 males, 521 females). Results The magnitude of the angle was 0.2 ± 1.4 and 0.3 ± 1.3 degrees (mean ± SD) in males and females, respectively. Faces were classified into 3 types relative to the parallel type. The incidence of the parallel type, the right-dominant type (≥1 degree), and the left-dominant type (≤1 degree) was 54.7%, 28.6%, and 16.7%, respectively. The right-dominant type was observed more frequently than the left-dominant type in both genders. Conclusion Our findings concur with those of previous studies of facial asymmetry and suggest that measurement of horizontal angulations of frontal photographs of faces can be used to assess facial asymmetry.

The infraorbital nerve (ION) supplies the skin and mucous membranes of the middle portion of the face. This nerve is vulnerable to injury during surgical procedures of mid-face. Severe pain and loss of sense are noted in patients whose infraorbital nerve is either entirely or partially lost after these surgeries. We investigated the distribution area and topography of the ION, about which little is currently known, by dissecting 43 hemifaces of Korean cadavers. The ION produced four main branches, the inferior palpebral, internal nasal, external nasal, and superior labial branches. The inferior palpebral branch was generally bifurcated, giving off a medial and a lateral branch (58.1%). The internal nasal branch ran superior to the depressor septi muscle, along the ala of the nose. It supplied the skin of the philtrum and gave off a terminal branch that supplied the nasal septum and the vestibule of the nose. The external nasal branch was distributed diversely supplying areas between the root and the ala of the nose. The superior labial branch was the largest branch of the ION produced the most subbranches. These subbranches were divided into the medial and lateral branches depending upon the area that they supplied.

Summary The purpose of the present study was to quantify the asymmetry of the palpebral fissure (PF) and upper eyelid crease in normal Koreans. Photographs were taken of 273 males and 321 females aged from 20 to 49 years with a standard head position and eyes open. We investigated the presence of asymmetries of the PF inclination (PFI), PF height (PFH), PF width (PFW) and the upper eyelid crease. The criteria for asymmetry were 2° for PFI, 1mm for PFH and 3mm for PFW. The PFH was larger on the right side than on the left side, whereas the PFW was larger on the left than on the right. The prevalence of asymmetry of the PFI, PFH and PFW was 22.3%, 24.2% and 18.3% in males, and 35.8%, 26.5% and 18.7% in females, respectively. In most cases of PF asymmetry, the PFH was larger on the right and the PFW was larger on the left. A left-only upper eyelid crease was more common than a right-only upper eyelid crease in both sexes. The asymmetry of the PF was generally more common in females.

The clinical significance of the muscular branch of the circumflex scapular artery (CSA) has been underestimated during surgery involving the scapular osteocutaneous free flap, while the suprascapular artery (SSA) is vulnerable to damage during internal fixation of a scapular fracture. This study aimed to provide navigational guidelines for the positions of the suprascapular and circumflex scapular arteries at the infraspinous fossa and to identify the anastomotic pattern. Scapulae were carefully dissected following injection of liquid silicone into the suprascapular and circumflex scapular arteries. The artery diameters and the distances between landmarks were measured. Scapulae were classified according to the anastomotic morphology of the arteries. The suprascapular and circumflex scapular arteries had mean diameters of 1.7 and 2.1 mm, respectively. The mean horizontal distance from the root of the spine to the suprascapular artery was 90.3 mm, and the mean distance between the suprascapular and circumflex scapular arteries was 45.5 mm. The circumflex scapular artery was positioned along the lateral border at 68.7% from the inferior angle. Practical navigational guidelines for the positions of the suprascapular and circumflex scapular arteries have been provided, with the anastomotic pattern classified into two types and two subtypes. The results of the present study will help reduce donor-site morbidity and damage to these arteries during surgery in the scapular region.

The aim of this study was to provide a clear description of the course, precise branching pattern and distribution of the deep branch of the ulnar nerve. A total of 36 hands from 18 preserved cadavers were dissected. The vertical distance from the pisoscaphoid line to the crossing points between the deep branch of the ulnar nerve and each metacarpal was about 4 cm. The deep branch of the ulnar nerve gave off two types of muscular branches: (1) trunks that innervate more than two intrinsic hand muscles; and (2) multiple separate branches innervating only a single muscle. The median numbers of trunks and separate branches were 5 and 6, respectively.Levels of Evidence: N/A

In a 30-year-old man, bilateral Kirner's deformity has been diagnosed. In the fully extended finger, the long axes of the middle and terminal phalanges formed an angle of 10 degrees in the volar and 5 degrees in the radial direction. Owing to the altered morphology of the distal phalanx, its palmar surface was at an angle of 25 degrees to the long axis of the middle phalanx. The deformity has existed since birth and has not changed except in size. His mother had the same bilateral deformity. Other closer relatives showed a unilateral appearance of Kirner's deformity: his maternal grandmother and an uncle had in their right little finger and an aunt had in her left little finger. Although some authors reported that Kirner's deformity was progressive, the description only referred to a change in the deformity. Kirner's deformity may be classified according to its period of onset, i.e., a more frequently occurring early type and a late type of onset (with lower incidence) exists. Moreover, it can be further classified by typical morphologic changes as well as the family history of the affected person.

This study examines the anatomic relationships and variability of the facial nerve trunk and its branches, with emphasis on the intraparotid connections between the divisions. Microdissections were performed on 30 Korean half-heads, and the facial nerve trunks and branches were exposed. The average depth of the stylomastoid foramen from the skin surface was 21.0 +/- 3.1 mm, and the distance between the stylomastoid foramen and the bifurcation of the temporofacial (upper) and cervicofacial (lower) divisions was 13.0 +/- 2.8 mm. In 26 of 30 dissections (86.7%), the facial nerve trunk bifurcated into two main divisions, and a trifurcation pattern was seen in the other four cases (13.3%). According to the origin of the buccal branches, we classified the branching patterns of the facial nerve into four categories. In type I (13.8% of cases), the buccal branches arose from the two main divisions of the trunk but not from other branches of the facial nerve. In type II (44.8% of cases), the buccal branches arising from the two main divisions were interconnected with the zygomatic branch. In type III (17.3% of cases), the marginal mandibular branch sent nerve twigs to the buccal branch, which originated from the upper and lower divisions. In type IV (17.3% of cases), the nerve twigs from the zygomatic and marginal mandibular branches merged to the buccal branch arising from the two main divisions. Communications between the facial and auriculotemporal nerve branches, which are known as "communicating auriculotemporal nerves," were observed in 28 of the 30 cases (93.3%). Familiarity with these common variations in the facial anatomy provides useful information for the surgeon in careful dissection, preservation of the facial nerve, and complete removal of the tumors in parotidectomies.

The topography and the course of the facial artery were investigated in 47 Korean cadavers. The final branch of the facial artery was the lateral nasal branch in 44.0% whereas it was the angular branch in 36.3% of the cases. In 54.5% of the cases, the facial artery ended symmetrically. According to previous studies, variations in the distribution pattern of the facial artery have been regarded as racial difference. However, in this study we showed that the diverse pattern of the facial artery distribution demonstrates individual variation rather than racial difference. The superior and inferior labial arteries on the right side were more dominant than those on the left. The average distance between the branching points for the inferior alar branch and for the lateral nasal branch was 15.9 mm, and it was 25.2 mm between the points for the superior labial branch and for the inferior alar branch. The branching point of the inferior labial branch was 30.9 mm apart on average from that of the superior labial branch. The courses of the facial arteries showed no significant differences based on either laterality or gender.

The aim of this study was to examine in detail the anatomic variations in the orbicularis oculi muscle (OOc) and relationship of the zygomaticus minor muscle (ZMi) with the OOc, thereby providing an anatomic basis for explaining facial animation and attachment to the periorbital muscle. Sixty-one hemifaces from embalmed Korean adult cadavers (34 males, 27 females; age range, 45-85 years; mean age, 62.6 years) were used in this study. The prevalence of cases in which the ZMi did not run straight from the upper lip, rather running straight to the corner of the levator labii superioris, was 36.1% (22/61), because the origin of ZMi covered the inferior border of the OOc. The prevalence of mixing of the belly of the orbital part of the outer edge of the OOc with the ZMi was 88.5%, and that of blending of the ZMi band into the lower inner corner of the OOc was 55.7%. The area of blending of the OOc and ZMi was located 17.8 mm down from the Frankfort plane and 8.9 mm lateral to the vertical line between the lateral canthus and the Frankfort plane in the lateral part of the OOc. At this position, the mixed belly extends medially for a distance of 16 mm. This research has identified the exact location where the ZMi and OOc blend and determined the relationship between the ZMi and the suborbicularis oculi fat. This result will be given as basic data for understanding facial expressions and for performing composite rhytidectomy.

The purpose of this study was to evaluate the anastomotic relationships between the accessory nerve and the posterior root of the first cervical nerve and to determine the course of the posterior root nerve fibers after anastomosis. The relationships between these two nerves were studied in 100 sides of the spinal cord and then classified into four types. In the most common type of anastomosis (38% of cases), either a branch from the posterior C1 root was seen to course cranially and join the accessory nerve, or the posterior root and accessory nerve fused as they coursed orthogonal to one other. In the second most common type (36% of cases), the accessory nerve anastomosed with a posterior C1 root that had no direct connection with the spinal cord; the nerve fibers of the posterior root were observed in stained samples to course caudally along the accessory nerve and join the posterior C2 root. In the least common type (6% of cases), no connection was observed between the accessory nerve and the posterior C1 root. In the next least common type (20% of cases), the posterior C1 root was absent and a connecting branch was sometimes observed between the accessory nerve and the anterior C1 root. Clin. Anat. 15:267–270, 2002. © 2002 Wiley-Liss, Inc.

Objective: The aim of this study was to clarify the anatomic variations of the intrathoracic nerve of Kuntz, and this should help delineate the resection margins during video-assisted thoracic sympathectomy. Methods: Sixty-six thoracic sympathetic chains of 39 adult Korean cadavers were dissected on both sides of the thorax in 27 cadavers (54 sides) and on one side in 12 cadavers (12 sides). Results: The intrathoracic nerve was observed in 45 (68.2%) sides and was present bilaterally in 48.1% of cadavers. No intrathoracic nerve or ascending ramus communicans arising from the second thoracic nerve was observed in only 5 (7.6%) sides. The diameter of the intrathoracic nerve was 1.25 ± 0.55 mm on average. The arising point of the intrathoracic nerve from the second thoracic nerve was 7.3 mm on average from the sympathetic trunk. Presence of the stellate ganglion was noted in 56 (84.8%) sides, and 6 (9.1%) sides showed a single large ganglion formed by the stellate and the second thoracic sympathetic ganglia. The second thoracic sympathetic ganglion was most commonly located (50%) in the second intercostal space. Conclusion: The anatomic variations of the intrathoracic nerve of Kuntz and the second thoracic sympathetic ganglion were characterized in human cadavers. It is hoped that this study will help to improve the recurrence of symptoms caused by the intrathoracic nerve in an upper thoracic sympathectomy for hyperhidrosis. J Thorac Cardiovasc Surg 2002;123:498-501

The aims of this study were to provide the various dimensions of the philtrum and upper red lip in Korean young adults and to identify morphological characteristics of these structures in Koreans. A total of 10 dimensions of the philtrum and upper red lip were measured in 251 healthy young adults. Various indices were calculated among the measured features. The philtrum could be classified into three types according to its shape and index data. The mean height of the philtrum was 15.6 mm and the mean width of the mouth was 45.5 mm. The width of the superior and inferior philtrum, the height of philtrum, the width of the mouth, and the height of the upper red lip were significantly larger in males than in females (p

Summary Purpose The purpose of this study was to identify the location of the trochlea in order to prevent injury during orbitofacial surgery and to determine the reliability of the lacrimal caruncle as a visible external landmark for the trochlea at the superomedial orbital rim. Methods Fifty-one orbits from 27 embalmed cadavers were dissected. The lacrimal caruncle and supraorbital notch/foramen were used as external and bony landmarks, respectively. The location of the trochlea was determined with respect to these structures, and the size of trochlea was measured. Results The trochlea was 3.6 mm wide and 5.6 mm long, with a flange breadth of 5.4 mm. The vertical distance from the apex of the lacrimal caruncle to the superolateral tip of the trochlea was 15.8 mm, and that from the top of the supraorbital notch/foramen to the bottom of the trochlea was 11.4 mm. As the coefficient of variation and standard deviation were smaller for DCT (11.5 and 1.8, respectively) than for DST (17.0 and 1.9, respectively), it appears that the lacrimal caruncle is a reliable landmark. Conclusions In contrast to the supraorbital notch, the lacrimal caruncle allows easy identification and serves as a reliable and visible external landmark for the prediction of the location of trochlea. The trochlea was located directly at 15.8 mm (i.e., approximately 1.5 cm) superior to the lacrimal caruncle. This anatomical study has yielded accurate measurements of the location of the trochlea, which may facilitate a safer orbitofacial surgery by preventing morbidity associated with trochlea injury.

Anterior interosseous nerve palsy is known to occur uncommonly due to the compression of the nerve by the accessory head of flexor pollicis longus (AHFPL). This study was conducted to investigate the prevalence and origin of the AHFPL and the topographical relationship between the AHFPL and the anterior interosseous nerve in Asians. The AHFPL was present in 48 of 72 arms examined (66.7%), a majority of which originated from the coronoid process. The anterior interosseous nerve was observed to arise from both the medial and posterior aspects of the median nerve. The topographical relationship between the anterior interosseous nerve and the AHFPL was classified into three types depending on if the anterior interosseous nerve crossed the muscular part, or the tendinous part of the AHFPL, or coursed lateral to the AHFPL. The case in which the anterior interosseous nerve crossed the muscular part of the AHFPL occurred most frequently in the current study. The types in which the anterior interosseous nerve may be compressed were also discussed. Clin. Anat. 13:434–438, 2000. © 2000 Wiley-Liss, Inc.

The current study investigated the anatomy of the infraorbital canal (IOC) and its related small canals in the maxilla. Twenty-eight hemimaxillae from human cadavers were studied. The samples were scanned using microcomputed tomography, and then images were three-dimensionally reconstructed using computer software. The branch point of the canal into the anterior superior alveolar nerve from the IOC occurred at about one third along the length of the IOC in the anterior direction. Just over half of the cases had 1 canal. The branch arose either laterally (21/28) or inferiorly (7/28) from the IOC. There was a canal located at the inferior lateral border of the piriform aperture in all cases. The distribution of the canals in the maxilla is represented indirectly by the course and distribution of the nerve and blood vessels therein. This distribution could explain various phenomena encountered in the clinical field.

Many Asians have faces with prominent zygomas, and therefore reduction malarplasty is one of the most frequently undergone surgeries in Asia, including South Korea. It is performed using various surgical approaches (external, intraoral, bicoronal or their combination). The reduction technique that is the most effective, safest and with the lowest morbidity needs to be determined. From December 2005 to January 2010, 1652 patients who wanted to undergo zygoma reduction for purely aesthetic reasons were operated on using a novel technique that we have developed (the 3S technique), which is a simple and safe surgical technique that results in only a short scar. First, under local anaesthesia, a 13- to 15-mm-long skin incision is made at each sideburn. The subperiosteal dissection is continued anteriorly all the way to the body of the zygoma. Zygoma reduction is then performed in three steps: (1) malar shaving (lateral area of the zygoma body), (2) lateral corticotomy (zygomatic arch) and (3) full-thickness osteotomy (pretubercular area of the temporomandibular joint). Next, the zygomatic arch is displaced medially with digital pressure (infracture). Finally, a Silastic drain is inserted through the incision site, skin repair is completed and a gentle compressive dressing is applied. Most of the patients were satisfied with the results of the operation. This technique provides the following advantages: (1) it is simple and safe because it is performed under only local anaesthesia; (2) only one scar is created at the sideburn; (3) no foreign bodies, such as wires or miniplates, are used; and (4) it is minimally invasive, and as such there are fewer potential complications (e.g., no cheek drooping due to a wide muscle incision or dissection, less oedema and bleeding and a short hospitalisation time). The presented technique is simpler and more effective than previously described surgical techniques for reduction malarplasty.

Improvements in both living standards and incomes have meant that many more people are now able to undergo elective plastic surgery for facial improvement. The nose and midface are the most frequent surgical target in Korea. However, the lack of reliable and precise anthropological data is a hindrance for effective surgical applications in this area. In the current study, 21 different lengths and angles of the midface and nose were measured in 2065 volunteers. The data were analyzed to establish sex and racial differences. Most of the measurements obtained from male volunteers were 5% to 10% greater than for the females, exceptions being the nasofrontal, nasolabial, and nasal tip angles. The biggest sex difference was found for depth of pupil, and the smallest difference was for intercanthal distance. For each measurement, the ratio of proportional differences was similar to that for whites. Many Koreans exhibited a columella protrusion of 4 to 5 mm; that parameter measures 2 to 3 mm in whites. The prevention of a hanging columella is important in nasal tip surgery. The intercanthal distance was also relatively large compared with the facial width. In females, the intercanthal distance was similar to the length of the nasal dorsum and the width of the nose. Surgeons may find this analysis useful for surgical planning. The present study provides basic clues for planning and practice in reconstructive and aesthetic facial surgery.

The maxillary artery (MA) passes over the lateral pterygoid muscle in the infratemporal fossa and enters the pterygopalatine fossa through the pterygomaxillary fissure. Refractory epistaxis is managed by ligation of the sphenopalatine artery via a transmaxillary-transantral approach; there is considerable risk of complications associated with such invasive surgical approaches. The aim of this study was to describe the gross anatomy and variations therein of the MA and its branches at the pterygopalatine fossa. One hundred hemifaces of embalmed Korean adult cadavers were dissected to establish the precise course of the MA and its branching patterns. The average thickness of the posterior wall of the maxillary sinus was 0.8 mm, but varied over a wide range from 0.2 to 3.6 mm. We classified the third part of the MA into 3 morphological categories: looped (61%), bifurcated (19%), and straight (18%). Two cases could not be classified into any of these 3 categories. The pattern of the bifurcation between the sphenopalatine and descending palatine arteries was classified into 4 types: Y (19%), intermediate (36%), M (17%), and T (28%). The posterior wall of the maxillary sinus was divided into 9 sections. The branching areas of the sphenopalatine and descending palatine arteries were most frequently (62% of cases) located at the top of the medial partition and at the middle of the medial partition (30% of cases).

The levator labii superioris (LLS) muscle is well known as one of the upper-lip elevators; however, there have been few reports about the anatomic description of the LLS. Especially, the shape of the LLS and its relationship with the nasal ala were not clearly shown in the literature. The aim of this study was to clarify and describe the morphology and topography of the LLS and the anatomic variations to understand the function of the LLS related with the nasal ala. The LLS was examined in 102 specimens of embalmed Korean and French adult cadavers. The LLS was classified into 3 categories according to its shape and attachment: rectangular (83%), fan (10%), or trapezoid (7%) type. The medial fibers of the LLS were attached to the deep surface of the alar facial crease and were mainly intermingled with the alar part of the nasalis. Some of the deeper muscle fibers of the LLS extended to the vestibular skin of the nasal lobule. These new anatomic findings in the current study could be useful information for understanding the function of the LLS and the various surgical procedures of the perinasal region.

It is well known that the head and face are smaller in female subjects than in male subjects. However, almost all previous studies have quantified the size difference between female and male subjects as simple numerical values, which might not clarify the difference. The present study evaluated the female-to-male proportions of the head and face so as to clarify the sex-related differences. A total of 1939 female subjects and 1398 male subjects were divided into 3 age groups: young (20-39 y), middle-aged (40-59 y), and elderly (60-79 y). The dimensions were classified into 3 categories: 5 cephalic, 3 frontal facial, and 6 lateral facial. The female-to-male proportions of individual dimensions were compared in the 3 age groups using the following formula: female measurement value × 100/(mean of male measurement value). The female-to-male proportions of the cephalic dimension increased with age, with the female cephalic dimensions overall being about 96% of the male cephalic dimensions. The female-to-male proportions of the frontal facial dimension were constant across the age groups, with the female frontal facial dimensions overall being 95% of the male frontal facial dimensions. The female lateral facial dimension increased markedly from the young to middle-aged group and was constant or decreased slightly from the middle-aged to the elderly group. Overall, the female lateral facial dimensions were approximately 97% of the male lateral facial dimensions. The present study will suggest a new approach to elucidate those sex-related dimensional differences that are characteristic of female and male subjects.

Objectives The purpose of this study was to investigate the general structure of the incisive canal (IC) using 3-dimensional reconstruction and to classify into various types according to several criteria. Study design The materials used in the study were 56 anterior maxillae harvested from human cadavers. The specimens were scanned with microscopic computerized tomography (microCT), and the resulting microCT images were reconstructed in 3 dimensions. Results Many ICs had 1 foramen inferiorly and 2 foramina superiorly, and the separating level was just beneath the nasal floor. The middle part of the IC was not always a single hollow canal. Single-channel, 2-channel, 3-channel, and even 4-channel ICs were observed. The ICs were classified into 4 types according to the lateral shape of the canal: vertical-straight, vertical-curved, slanted-straight, and slanted-curved. Conclusions This study disclosed the detailed morphologic features of the IC, which will be helpful in the placement of local anesthesia or implants.

The dramatic changes in facial expression are most remarkable in the perioral region. Among the perioral musculatures, the zygomaticus major (ZMj) muscle plays an important role in the facial expression. The aim of this study was to determine the anatomic patterns of the bifid ZMj through a topographic examination at the perioral region. Through 70 dissections of the hemifaces, the insertion area of the ZMj was observed in 70 embalmed cadavers. The bifid ZMj was observed in 28 cases (40%). In most cases of the bifid ZMj, the superior muscle fibers were larger and wider than the inferior fibers. Bilateral bifid ZMj was found in 71.4% of the bifid ZMj specimens. The arrangement and insertion patterns of the ZMj in this study are expected to provide critical information for the surgical planning and procedure for facial reanimation surgery.

Background The purpose of the present study was to determine the locations of the infraorbital foramen and mental foramen based on soft-tissue landmarks to facilitate prediction of the locations of these structures during facial surgery. Methods Fifty embalmed cadavers (100 sides) of Koreans were dissected to expose the infraorbital foramen and mental foramen. The distances between the bilateral infraorbital foramina and between the mental foramina and the distances between the alae of the nose and between the corners of the mouth (cheilions) were measured directly on the cadavers, and the vertical and horizontal distances between the infraorbital foramen and mental foramen and the ala of the nose and cheilions, respectively, were measured indirectly on photographs. Results The distance between the bilateral infraorbital foramina (54.9 +/- 3.4 mm) was greater than that between the bilateral mental foramina (47.2 +/- 5.5 mm). The infraorbital foramen was located 1.6 +/- 2.7 mm lateral and 14.1 +/- 2.8 mm superior to the ala of the nose. The distance between the ala of the nose and the infraorbital foramen was 15.9 +/- 2.8 mm, and the horizontal angle between these structures was 64.1 +/- 9.9 degrees laterosuperiorly. The mental foramen was located 20.4 +/- 3.9 mm inferior and 3.3 +/- 2.9 mm medial to the cheilions. The distance between the cheilions and mental foramen was 20.9 +/- 3.8 mm, and the vertical angle between these structures was 9.2 +/- 8.1 degrees inferomedially. Conclusions This study provides data that will be useful in predicting the locations of the infraorbital foramen and mental foramen when used together with hard-tissue landmarks. These data may be particularly helpful for facial surgery in patients with missing teeth.

The purposes of this study were therefore to characterize the degeneration and regeneration of nerves to the calf muscles after selective neurectomy, both macroscopically and microscopically, and to determine the incidence of such regeneration in a rabbit model. Seventy four New Zealand white rabbits were used. Selective neurectomy to the triceps surae muscles was performed, and the muscles were subsequently harvested and weighed 1-4 months postneurectomy. The gastrocnemius muscles were stained with Sihler's solution to enable the macroscopic observation of any nerve regeneration that may have occurred subsequent to neurectomy. The change in triceps surae muscle weight was measured along the time course of the experiment. After neurectomy, nerve degeneration was followed by regeneration in all cases. The weight of the triceps surae muscle decreased dramatically between completion of the neurectomy and 1 month postneurectomy, but increased thereafter. The nerve branches were weakly stained with Sihler's solution until 2 months postneurectomy, and then strongly stained after 3 months. The number of myelinated axons was decreased at 2 month after neurectomy compared to nonneurectomized controls, but then gradually increased thereafter. Although there are currently no reports on the incidence of recovery after calf reduction, it may be a very common occurrence in the clinical field based on our findings. The findings of this study provide fundamental anatomical and surgical information to aid planning and practice in calf-reduction surgery.