Soon-Heum Kim

Topographic anatomy of the zygomatic arch and temporal fossa: A cadaveric study

The zygomatic arch (ZA) is a long, slender and laterally protruding structure of the face that is vulnerable to fracture by various types of trauma. Knowledge of the topographic anatomy of the ZA and temporal fossa is important for appropriate management of ZA problems. Thirty-seven male and 33 female cadavers were investigated in this study. Skin, subcutaneous tissue, fascia and periosteum were completely removed from around the ZA. Several depths and distances were measured based on three landmarks on the ZA: the anterior, middle and posterior portions of its superior margin. The thickness of the ZA was relatively constant in the three portions. The distance from the internal surface of the ZA to the surface of the temporalis muscle was similar in the anterior and middle portions, at about 8mm, and slightly lesser in the posterior portion. The distance from the external surface of the ZA to the temporal bone was the greatest at the anterior portion, and there was a large difference between the anterior and middle portions. The temporalis muscle was the thickest in the anterior portion and the thinnest in the posterior portion. This study suggests that the maximum distance from the internal surface of the ZA to the surface of the temporalis muscle is 8mm, and this should be considered when performing reduction malarplasty on the ZA.

Anatomical Verification and Designation of the Superficial Layer of the Temporalis Muscle

The temporalis muscle, which is one of the masticatory muscles, enables elevation and retraction of the mandible. Direct injury to the temporalis muscle, facial nerve, or temporal fat pad during cranial‐base surgery can cause temporal hollowing. The temporalis muscle is currently described in almost all atlases and textbooks as comprising a single layer. In this study, a superficial layer of the temporalis muscle is described, clarifying the anatomy of this muscle. Twenty heads of adult cadavers were dissected. The gross anatomy of the temporalis muscle was examined after removing the skin, subcutaneous tissue, superficial temporal fascia, and deep temporal fascia. The superficial layer of the temporalis muscle was clearly distinguishable from the deep layer. The superficial layer originated from the same region as the deep layer, and the muscle fibers of the two layers were intermingled in the superior part of the muscle. The deep layer of the temporalis muscle, which is referred to in textbooks and atlases simply as the temporalis muscle, was exposed after removing the superficial layer. The existence of this superficial layer was confirmed herein both histologically and by magnetic resonance imaging. Henceforth, the superficial layer of the temporalis muscle must be included in descriptions of the temporalis muscle in anatomy textbooks and atlases. The findings of this study are important not only from the perspective of simply acquiring correct anatomical knowledge, but also from the surgical perspective in preventing temporal hollowing during related surgical procedures. Clin. Anat. 25:176–181, 2012.

Secondary Cleft Nasal Deformity Correction Using Bioabsorbable Mesh.

Introduction:Septorhinoplasty in cleft patients is relatively difficult to perform and the outcomes are often unsatisfactory owing to weakness of the cartilage. Therefore, providing support to the cartilage is necessary. The authors used bioabsorbable mesh as a spreader or batten graft to support the septum in cleft patients those with weak cartilages. The purpose of this study was to evaluate the efficacy of bioabsorbable mesh when performing septorhinoplasty in cleft patients. Methods:Between 2009 and 2013, 34 patients with cleft lip and nose underwent open septorhinoplasty by using bioabsorbable mesh at the Konkuk University Medical Center. The authors determined the nasolabial angle, Goode ratio, alar base-nasal tip-columellar base angle, and columellar axis angle and performed a panel evaluation. Results:In all, 29 of the 34 patients were included; 5 patients were excluded as lost to follow-up. The nasolabial angle increased from 85.69° to 91.62° (P = 0.0032), and the mean Goode ratio increased from 0.51 to 0.55, which was approximately the ideal value (P = 0.0017). The alar base-nasal tip-columellar base angle decreased from 36.28 to 31.74 (P < 0.0001). The columellar axis angle increased from 82.36 to 86.90 (P < 0.0001). Discussion:As bioabsorbable mesh can provide strong support, results in good esthetic outcomes, and causes minimal complications, it can be used in septorhinoplasty for cleft patients.

Topographic relationships between the transverse facial artery, branches of the facial nerve, and the parotid duct in the lateral midface in a Korean population.

BackgroundThe 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. MethodsThirty-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. ResultsThe 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. ConclusionsThese 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.

Centralization or decentralization of facial structures in Korean young adults.

AbstractIt is well known that facial beauty is dictated by facial type, and harmony between the eyes, nose, and mouth. Furthermore, facial impression is judged according to the overall facial contour and the relationship between the facial structures. The aims of the present study were to determine the optimal criteria for the assessment of gathering or separation of the facial structures and to define standardized ratios for centralization or decentralization of the facial structures.Four different lengths were measured, and 2 indexes were calculated from standardized photographs of 551 volunteers. Centralization and decentralization were assessed using the width index (interpupillary distance / facial width) and height index (eyes-mouth distance / facial height). The mean ranges of the width index and height index were 42.0 to 45.0 and 36.0 to 39.0, respectively. The width index did not differ with sex, but males had more decentralized faces, and females had more centralized faces, vertically. The incidence rate of decentralized faces among the men was 30.3%, and that of centralized faces among the women was 25.2%.The mean ranges in width and height indexes have been determined in a Korean population. Faces with width and height index scores under and over the median ranges are determined to be “centralized” and “decentralized,” respectively.

Assessment of Normal Eyeball Protrusion Using Computed Tomographic Imaging and Three-Dimensional Reconstruction in Korean Adults.

ABSTRACT Purpose: The aim of the present study was to assess normal eyeball protrusion from the orbital rim using two- and three-dimensional images and demonstrate the better suitability of CT images for assessment of exophthalmos. Methods: The facial computed tomographic (CT) images of Korean adults were acquired in sagittal and transverse views. The CT images were used in reconstructing three-dimensional volume of faces using computer software. The protrusion distances from orbital rims and the diameters of eyeballs were measured in the two views of the CT image and three-dimensional volume of the face. Relative exophthalmometry was calculated by the difference in protrusion distance between the right and left sides. Results: The eyeball protrusion was 4.9 and 12.5 mm in sagittal and transverse views, respectively. The protrusion distances were 2.9 mm in the three-dimensional volume of face. There were no significant differences between right and left sides in the degree of protrusion, and the difference was within 2 mm in more than 90% of the subjects. Conclusions: The results of the present study will provide reliable criteria for precise diagnosis and postoperative monitoring using CT imaging of diseases such as thyroid-associated ophthalmopathy and orbital tumors.

The effect of the dental root on single mandibular bone fractures

Background This study was conducted to determine the effect of the distributional relationship between dental roots and the mandibular bone on single mandibular bone fractures, which are common craniofacial fractures. Methods This was a retrospective, single-center study in Seoul, Korea. Patients with single mandibular fractures in the symphysis, parasymphysis, body, and angle area, with tooth structure involvement were included. The control group included patients with simple, bone-level lacerations without fractures. In total, 94 patients (72 males and 22 females) were included in the treatment group, and 125 (71 males and 54 females) were included in the control group. The height of the mandibular bone and the dental root were measured with panoramic radiography. The central incisor represented the symphysis area, the canine represented the parasymphysis area, the first molar represented the body area, and the second molar represented the angle area. Results In the treatment group, symphysis fractures occurred in 16 patients (17%), parasymphysis fractures in 36 patients (38%), body fractures in 17 patients (18%), and angle fractures in 25 patients (27%). The ratios of the dental roots to the total height of the mandibular bone in the treatment group were 30.35%, 39.75%, 39.53%, and 36.27% for symphysis, parasymphysis, body, and angle areas, respectively, whereas in the control group, they were 27.73%, 39.70%, 36.76%, and 35.48%. The ratios of the treatment group were significantly higher than those of the control group. Conclusion The results show that the higher ratio of the dental root to the height of the mandibular bone increases the fracture risk.

Autogenous Fat Grafting for Mild-to-Moderate Postoperative Temporal Hollowing after Decompressive Craniectomy: 1-Year Follow-Up

Background Temporal hollowing is inevitable after decompressive craniectomy. This complication affects self-perception and quality of life, and various techniques and materials have therefore been used to restore patients’ confidence. Autologous fat grafting in postoperative scar tissue has been considered challenging because of the hostile tissue environment. However, in this study, we demonstrate that autologous fat grafting can be a simple and safe treatment of choice, even for postoperative depressed temporal scar tissue. Methods Autologous fat grafting was performed in 13 patients from 2011 to 2016. Fat was harvested according to Coleman’s strategy, using a tumescent technique. Patient-reported outcomes were collected preoperatively and at 1-month and 1-year follow-ups. Photographs were taken at each visit. Results The thighs were the donor site in all cases for the first procedure. The median final volume of harvested fat was 29.4 mL (interquartile range [IQR], 24.0–32.8 mL). The median final volume of fat transferred into the temporal area was 4.9 mL on the right side (IQR, 2.5–7.1 mL) and 4.6 mL on the left side (IQR, 3.7–5.9 mL). There were no major complications. The patient-reported outcomes showed significantly improved self-perceptions at 1 month and at 1 year. Conclusions Despite concerns about the survival of grafted fat in scar tissue, we advise autologous fat grafting for patients with temporal hollowing resulting from a previous craniectomy.

Anatomical characteristics of the nasal cartilages for successful rhinoplasty in Koreans.

BackgroundsThe 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. MethodsWe dissected and photographed 60 sides of noses; 18 specimens were sectioned and stained with Masson’s trichrome. ResultsThe 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. ConclusionsThe 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.