Extended Maxillotomy for Nasopharynx Access in Infantile Immature Teratoma.

Infantile immature teratoma located in the nasopharynx is a rare congenital tumor that is not easily removed. Three surgeries and chemotherapy for recurrence of the tumor have been performed since a male infant with a nasopharyngeal mass was born at a gestational age of 35 weeks. Extended maxillotomy combining Le Fort I osteotomy with midline palatal split was performed at 2 years and 6 months of age. Residual tumor left in the intracranial region had not increased as of 4 years of age. Careful follow-up is needed until the patient reaches adulthood.

Evaluation of Congenital Maxillary Growth Using Computed Tomography in Patients With Bilateral Cleft Lip and Palate.

OBJECTIVE: To analyze congenital lateral maxillary growth for patients with bilateral cleft lip and palate (BCLP). DESIGN: A retrospective study. SETTING: Kanagawa Children's Medical Center. MATERIALS: Images from computed tomography (CT) of patients with BCLP and control patients that were previously used for treatment. MAIN OUTCOME MEASURES: The following landmarks were used: A, the posterior most point of the piriform aperture; B, the superior most point of the acoustic meatus; C, the point at which line A-B intersects the line drawn perpendicular from line A-B to the maxillary tuberosity; and D, the apical most point of the nasal bone. The following distances were then measured using these landmarks: (1) A-B distance; (2) A-C distance; (3) A-C/A-B; (4) the angle between lines A-B and A-D (∠BAD); and (5) B-D distance. RESULT: Mean A-B and A-C distances and A-C/A-B were significantly smaller in the BCLP group than in the control group (P < .01 each). Mean ∠BAD was significantly larger in the BCLP group than in the control group (P < .01). Mean B-D distance did not differ significantly between groups. CONCLUSIONS: Our results indicated that the lateral maxillary segments of patients with BCLP were more posterior than those of the control group, and segment length was shorter compared to the control group on 3D-CT analysis. The lateral maxillary segments of patients with BCLP were basically suggested to originally be underdeveloped.

Perinasal Osteotomy With Distraction Osteogenesis for a Mild Syndromic Craniosynostosis.

Le Fort II and III procedures have generally been performed for syndromic craniosynostosis with midfacial hypoplasia and skeletal class III malocclusion. However, some patients have midfacial hypoplasia without malocclusion. Perinasal osteotomy was performed with distraction osteogenesis to move the midface forward in 2 patients (a 17-year old female patient with Crouzon-like disease and a 15-year-old female patient with Antely-Bixler syndrome) with mild midface hypoplasia without malocclusion. The success of the procedure was assured by 3 features: the intermaxillary sutures were fixed by a mini metal plate to prevent separation during distraction; the distraction wires were fixed through the bone of the piriform aperture with the mini metal plates to prevent the wires from coming off; and the osteotomy line was designed in front of the palatomaxillary suture to avoid suture damage. These were expected to secure the procedure. Perinasal osteotomy with distraction osteogenesis is considered one of the recommended procedures for mild midfacial hypoplasia as seen in mild syndromic craniosynostosis without malocclusion.

Overcorrected Midface Advancement to Improve Airway Problems in Severe Pfeiffer Syndrome Types II and III.

INTRODUCTION: Treatment of patients with severe Pfeiffer syndrome types II and III is difficult. The purpose of this article is to present our method of overcorrecting midface advancement to improve airway problems in such patients. MATERIALS AND METHODS: One boy and two girls with types II and III Pfeiffer syndrome and who underwent Le Fort III midface advancement using our previously described corrected cephalometric analysis and distraction system were included in the study. RESULTS: The authors overcorrected by advancing the midface to make it look as similar as possible to an adult face. While the overcorrected midface advancement widened the upper airway spaces in the 3 patients, the tracheostomy that had already been placed during infancy could not be closed, probably because of an underlying tracheal abnormality or tracheomalacia. DISCUSSION: Overcorrected midface advancement cannot enable tracheostomy closure, probably because of severe tracheal anomalies, such as tracheomalacia, below the tracheostomy. However, with the possibility of gradual improvement of the tracheomalacia with age, closure of the tracheostomy can eventually be expected. Therefore, efforts to close a tracheostomy should be pursued even if the probability of its removal is low. CONCLUSION: Overcorrected midface advancement did not enable tracheostomy closure, probably because of severe tracheal anomalies such as tracheomalacia. However, the severe exophthalmos and angle III malocclusion were improved, and with the possibility of gradual improvement of the tracheomalacia with age, closure of the tracheostomy can eventually be expected. Therefore, efforts to close a tracheostomy should be pursued even if the probability of its removal is low.

Deltopectoral flap revisited for reconstruction surgery in patients with advanced thyroid cancer: a case report.

BACKGROUND: We present the cases of 2 patients with invasive thyroid cancer, who underwent reconstructive surgery using a deltopectoral flap. Although the overall rate of extrathyroidal extension in patients with thyroid cancer is quite low, skin invasion is the most common pattern observed. Reconstructive surgery, involving local skin flaps, is required in these patients. The deltopectoral flap relies on the blood supply from intercostal perforators of the internal thoracic artery and usually requires skin grafting to the donor site. The internal thoracic artery is rarely sacrificed in these cases, even in an advanced surgery such as in patients with invasive thyroid cancer. CASE PRESENTATION: A 55-year-old man with a distended thyroid gland presented to our hospital. He underwent advanced surgery, including skin excision, because we suspected that his tumor was thyroid cancer. The defect was covered with an ipsilateral deltopectoral flap via transposition of the flap, without skin grafting. In the second case, a 67-year-old woman with thyroid cancer that metastasized to her neck lymph nodes presented to our institution. Although the ipsilateral internal thoracic artery was sacrificed near its origin during tumor resection, the deltopectoral flap was raised in the usual manner without any complications. The skin defect caused by the tumor resection was covered with the flap. The patient had an uneventful clinical course for more than 2 years of follow-up. These 2 cases show the effectiveness of using the deltopectoral flap as a reconstructive option for patients with thyroid cancer who underwent radical surgery, resulting in a skin defect. The first case shows that this flap does not always require skin grafting to the donor site. To our knowledge, the second case may be the first report of a deltopectoral flap that was safely raised and applied with resection of the bifurcation of the ipsilateral internal thoracic artery. CONCLUSIONS: Although thyroid cancer surgery with surrounding skin excision is a rare procedure, we found that the deltopectoral flap was useful and should be the first choice for patients undergoing reconstructive surgery, whether the bifurcation of the ipsilateral internal thoracic artery is sacrificed.

Inhibition of Rho-associated kinases disturbs the collective cell migration of stratified TE-10 cells.

BACKGROUND: The collective cell migration of stratified epithelial cells is considered to be an important phenomenon in wound healing, development, and cancer invasion; however, little is known about the mechanisms involved. Furthermore, whereas Rho family proteins, including RhoA, play important roles in cell migration, the exact role of Rho-associated coiled coil-containing protein kinases (ROCKs) in cell migration is controversial and might be cell-type dependent. Here, we report the development of a novel modified scratch assay that was used to observe the collective cell migration of stratified TE-10 cells derived from a human esophageal cancer specimen. RESULTS: Desmosomes were found between the TE-10 cells and microvilli of the surface of the cell sheet. The leading edge of cells in the cell sheet formed a simple layer and moved forward regularly; these rows were followed by the stratified epithelium. ROCK inhibitors and ROCK small interfering RNAs (siRNAs) disturbed not only the collective migration of the leading edge of this cell sheet, but also the stratified layer in the rear. In contrast, RhoA siRNA treatment resulted in more rapid migration of the leading rows and disturbed movement of the stratified portion. CONCLUSIONS: The data presented in this study suggest that ROCKs play an important role in mediating the collective migration of TE-10 cell sheets. In addition, differences between the effects of siRNAs targeting either RhoA or ROCKs suggested that distinct mechanisms regulate the collective cell migration in the simple epithelium of the wound edge versus the stratified layer of the epithelium.

Influence of the frequency of laser toning for melasma on occurrence of leukoderma and its early detection by ultraviolet imaging.

BACKGROUND AND OBJECTIVE: Laser "toning" with a Q-switched neodymium-doped yttrium aluminum garnet (Nd:YAG) laser has recently been described to be effective for the treatment of melasma. Leukoderma is a refractory complication of laser toning for melasma, but it can be detected early with ultraviolet (UV) imaging. We assessed the relationship between leukoderma and the frequency or total number of laser toning sessions, as well as the effectiveness of UV imaging for detecting leukoderma. MATERIALS AND METHODS: The subjects included 147 patients who received at least five laser toning sessions. Subjects were classified into three groups according to the frequency of treatment (weekly for Group A1, fortnightly for Group A2, and monthly for Group B), and the incidence of leukoderma was compared among the three groups. In patients who developed leukoderma, the interval between clinical diagnosis and leukoderma detection on UV images (obtained with a Visia Evolution during every laser toning session) was determined to evaluate the effectiveness of UV imaging for the early detection of leukoderma. RESULTS: The overall incidence of leukoderma was 2% (3/147 patients): 3.8% (1/26 patients) in Group A1, 4% (2/49 patients) in Group A2, and 0% (0/72 patients) in Group B. There were no significant differences in the incidence of leukoderma relative to the frequency of laser toning. In two of the three patients who developed leukoderma, it was diagnosed clinically at the 20th and 21st laser toning session, whereas it was diagnosed by UV imaging at the 12th and 13th session. In the remaining 1 patient, leukoderma was detected clinically and by UV imaging at the 7th session. CONCLUSIONS: There was no significant difference in the incidence of leukoderma related to the frequency of laser toning. This study showed that there are two types of leukoderma associated with laser toning. UV imaging was effective for the early detection of type 1 leukoderma, which seems to be related to the cumulative laser energy delivered, but not for detecting type 2 leukoderma, which may be due to direct phototoxicity.

Dynamic blood flow to the retrograde limb of the internal mammary vein in breast reconstruction with free flap.

BACKGROUND: In free flap breast reconstruction, the retrograde limb of the internal mammary vein (IMV) is occasionally used as a second recipient vein. In this study, we evaluated the dynamic blood flow to the retrograde limb of the IMV (retrograde IMV) at the anastomosed site via indocyanine green (ICG) angiography METHODS: In 40 patients undergoing free flap breast reconstruction, we evaluated the dynamic blood flow as "stain(+)" if a stain by ICG was observed and, "flow(+)" if a smooth blood flow was recognized. RESULTS: Based on the ICG angiography, "stain(+)" was observed in all cases, but "flow(+)" was detected in only 72.5% of the cases. There was no severe complication. CONCLUSION: This study shows that thrombosis is prone to occur in the second recipient vein in the 27.5% of the cases with no smooth flow, and therefore, the retrograde IMV may not function as a back-up in these cases.

Orthognathic surgery with iliac bone grafting for an interpositional gap in a patient with type III hemifacial microsomia: A case report.

Hemifacial microsomia (HFM) is characterized by uni- or bilateral microtia and hypoplasia of the mandible, orbits, facial nerve, and adjacent soft tissues. Patients with Pruzansky-Kaban type III HFM show the most severe facial deformities and often encounter difficulty obtaining treatment. In recent years, orthognathic surgery for HFM-related deformities has often been performed after the patient has stopped growing. However, few detailed reports have described the difficulties of orthognathic surgery for patients with type III HFM. This report describes the case of a patient with type III HFM who underwent three unilateral mandibular reconstructions while still growing, including autogenous reconstructions and secondary distraction osteogenesis, followed by orthognathic surgery with iliac bone grafting for an interpositional gap between the proximal and distal segments after she had stopped growing to improve facial asymmetry and malocclusion.

Outcomes of lymphaticovenous side-to-end anastomosis in peripheral lymphedema.

OBJECTIVE: Lymphaticovenous anastomosis has been used for patients with peripheral lymphedema. However, the efficacy of this procedure is controversial due to a lack of evidence regarding postoperative patency. We sought to determine midterm postoperative patency of lymphaticovenous side-to-end anastomoses (LVSEAs) using indocyanine green fluorescence lymphography. METHODS: This was a retrospective observational study set in a teaching hospital. Of 107 patients with chronic lymphedema who underwent 472 LVSEAs, 57 (223 anastomoses) consented to fluorescence lymphography and comprised the study cohort. The intervention consisted of a microsurgical LVSEA performed with a suture-stent method. Patients also had preoperative and postoperative complex decongestive physiotherapy. Anastomosis patency was assessed using indocyanine green fluorescence lymphography ≥6 months after surgery. Patency rates were calculated using Kaplan-Meier analysis. We assessed volume reduction on the operated-on limb and compared this between patients in whom anastomoses were patent and those in whom anastomoses were not obviously patent. RESULTS: Patency could be evaluated only at the dorsum of the foot, ankle, and lower leg because the near-infrared rays emitted by the special camera used could not penetrate the deep subcutaneous layer containing collective lymphatics in areas such as the thigh. Several patterns were observed on fluorescence lymphography: straight, radial, and L-shaped. Cumulative patency rates of LVSEAs were 75% at 12 months and 36% at 24 months after surgery. No significant difference in volume change of the affected limb was seen between the 34 patients with patent anastomosis (600 ± 969 mL) and the 24 patients without obvious evidence of patency (420 ± 874 mL). CONCLUSIONS: Although further study is required to determine factors leading to anastomotic obstruction and to optimize the results of microlymphatic surgery, the present LVSEA technique appears promising.

Subacute phase treatment of subperiosteal hematoma of the orbit with epidural hematoma in the frontal cranial fossa: case report.

BACKGROUND: Subperiosteal hematoma of the orbit is one of the rare lesions that cause exophthalmos after craniomaxillofacial trauma. Presently, there is no consensus for how to treat this disease. Although some reports have suggested a conservative type of therapy, others have recommended surgical treatments be done during the early stages. CASE PRESENTATION: This case report provides details on the clinical course of a 9-year-old girl with subperiosteal hematoma of the orbit. In this particular patient, a rare case of ipsilateral subfrontal extradural hematoma was also observed. Due to our performing the surgical intervention during the subacute stage, functional complications as well as cosmetic problems were avoided. CONCLUSION: Our results demonstrate that surgical treatments for subperiosteal hematoma of the orbit should be delayed until it can be confirmed that a patient has no other complications. On the other hand, once it has been confirmed that the patient has no other existing problems, immediate surgical therapy with a small skin incision followed by the setting of a drain is recommended in order to achieve an early resolution and avoid complications.

Blepharoplasty in senile blepharoptosis: preoperative measurements and design for skin excision.

BACKGROUND: For patients with senile ptosis, aesthetic blepharoplasty can be combined with ptosis surgery. However, the amount of skin excision necessary in blepharoplasty is not clearly defined by measurements of the upper eyelids. OBJECTIVES: The authors preoperatively evaluate the amount of skin to be excised in blepharoplasty. METHODS: Fifty patients with bilateral senile ptosis were included in this study. The amount of skin to be excised from the upper eyelids was selected based on preoperative measurements of redundant skin, equivalent to the maximum lid height (MLH) while manually stretching the eyelid upwards minus resting lid height (RLH) with the eyes closed passively. Ptosis surgery (such as plication of the aponeurosis) followed blepharoplasty. RESULTS: Preoperatively, mean MLH was 35 mm on the right and 36 mm on the left. Mean RLH was 25 mm bilaterally. The mean amount (height) of excised skin was 10 mm on the right and 11 mm on the left. At six months postoperatively, mean MLH and RLH were 29 and 23 mm on both sides, respectively. Significant differences between pre- and postoperative MLH and RDH were seen on both sides (P<.001). No complications due to overexcision were observed, but revision was performed for two patients with asymmetry of the lid folds and five patients with recurrence of drooping. CONCLUSIONS: Preoperative measurements of upper eyelid heights (stretched and at rest) appear useful in determining the amount of skin excision required in blepharoplasty for senile ptosis. LEVEL OF EVIDENCE: 4.

A predictor of a postoperative fistula after double-opposing Z-plasty in bilateral cleft lip and palate patients.

Furlow double-opposing Z-plasty (FDOZ) as primary palatoplasty for the bilateral cleft lip and palate (BCLP) closure often leads to a palatal fistula formation in cases with wide clefts. We examined the utility of the calculated maximum closable cleft width to determine the feasibility of a direct palatal closure without lateral incisions. In this retrospective study, we analyzed consecutive patients with a BCLP who were treated for 5 years from 2009. In sixty-three BCLP patients, the following dimensions were measured preoperatively: an actual distance between maxillary tuberosities (Actual X); actual cleft height, calculated from the line joining the maxillary tuberosities to the cleft edge (Actual Y); and actual cleft width at the hard-soft palate junction (Actual Z) and calculated maximum cleft width requiring a direct closure (CMZ). Six months postoperatively, the relationships between the fistula occurrence and actual Z/CMZ were examined. Median values (interquartile range) of Actual X, Y, and Z and CMZ were 35.0 (33.0-39.0) mm, 7.0 (6.0-8.0) mm, 10.0 (8.0-11.0) mm, and 4.6 (2.7-5.7) mm, respectively. The median age at operation was 8.0 (7.0-17.0) months. Fistulae at the hard-soft palate junction developed postoperatively in three cases with more than a 10-mm cleft width (4.76%). A receiver operating characteristic (ROC) curve analysis indicated that actual Z was a better predictor of a postoperative fistula formation than CMZ. An actual cleft width was a better predictor of the fistula occurrence than a calculated maximum cleft width after FDOZ for a BCLP repair. The low fistula rate of FDOZ suggested that FDOZ could be used to close the palate with less than a 10-mm cleft width.

Posterior pharyngeal wall augmentation using autologous tiered costal cartilage for velopharyngeal insufficiency.

The aim of this study was to retrospectively estimate intervention outcomes and to establish suitable indications for autogenous tiered cartilage augmentation (ATCA) of the posterior pharyngeal wall for velopharyngeal insufficiency (VPI). The sample cohort comprised 17 consecutive patients with VPI (10 boys, 7 girls), excluding syndromic cases. Pre- and postoperative findings were comprehensively evaluated using a combination of speech assessment and lateral pharyngography (LPG). Hypernasality and consonant distortion were scored (normal: 0; mild: 1; moderate: 2; severe: 3). Velopharyngeal gap size at rest (AC) and at maximum closure (BC) were measured on LPG. All patients displayed improvements in velopharyngeal function and speech score, and no patients required re-operation. Pre- and postoperative hypernasality scores were 1.9 ± 0.5 and 0.6 ± 0.5, respectively (P < .001). Pre- and postoperative consonant distortion scores were 1.9 ± 0.6 and 0.6 ± 0.5, respectively (P < .001). Pre- and postoperative AC distances were 8.2 ± 3.4 mm and 5.9 ± 2.6 mm, respectively (P < .001). Pre- and postoperative BC distances were 3.9 ± 2.4 mm and 0.3 ± 0.8 mm, respectively (P < .001). Conclusions: ATCA appears effective for surgical treatment of VPI patients with a gap less than 10 mm.

In vitro elastic cartilage reconstruction using human auricular perichondrial chondroprogenitor cell-derived micro 3D spheroids.

Morphologically stable scaffold-free elastic cartilage tissue is crucial for treating external ear abnormalities. However, establishing adequate mechanical strength is challenging, owing to the difficulty of achieving chondrogenic differentiation in vitro; thus, cartilage reconstruction is a complex task. Auricular perichondrial chondroprogenitor cells exhibit high proliferation potential and can be obtained with minimal invasion. Therefore, these cells are an ideal resource for elastic cartilage reconstruction. In this study, we aimed to develop a novel in vitro scaffold-free method for elastic cartilage reconstruction, using human auricular perichondrial chondroprogenitor cells. Inducing chondrogenesis by using microscopic spheroids similar to auricular hillocks significantly increased the chondrogenic potential. The size and elasticity of the tissue were maintained after craniofacial transplantation in immunodeficient mice, suggesting that the reconstructed tissue was morphologically stable. Our novel tissue reconstruction method may facilitate the development of future treatments for external ear abnormalities.

Active middle ear implant (vibrant soundbridge) in children with unilateral congenital aural atresia.

BACKGROUND: Detailed studies have not been conducted on sound localization and speech perception in noise in patients with unilateral congenital aural atresia (UCAA). AIMS/OBJECTIVES: To evaluate the benefits of the use of the Vibrant Soundbridge (VSB) for UCAA by performing audiometric and sound localization tests. MATERIALS AND METHODS: Four children with UCAA underwent VSB (VORP 503) implantation from 2018 to 2019. Speech perception tests in noise were conducted using the Japanese monosyllable test. The spatial configuration for speech testing consisted of speech presented from the front and noise presented into the normal ear (S0N90). The sound localization test was conducted using nine loudspeakers equally distributed in a semicircle. RESULTS: The children's speech perception in noise 6 months after VSB activation was significantly better than before activation (p < .05). Additionally, the children's sound localization ability after VSB activation was significantly better than before VSB activation. CONCLUSION AND SIGNIFICANCE: The benefits of VSB use in children with UCAA were revealed using audiometric and sound localization tests.

A procedure combining double opposing Z-plasty with buccal flap and skin graft for a cleft palate patient with short palate.

Cleft palate patients with a short palate are sometimes encountered and it is difficult to achieve effective primary palatoplasty and good speech in these cases. Our purpose was to establish an effective palatoplasty for a cleft palate patient with Randall type III short palate. Buccal musculomucosal flap on the nasal side and skin graft on the oral side were performed, along with double opposing Z-plasty. Speech improved postoperation. This procedure brought the nasopharyngeal area closer to the normal anatomical state. In terms of disadvantages, the procedure is rather complicated and depends on the engraftment rate.

Contralateral unaffected breast augmentation using zone IV as a SIEA flap during unilateral DIEP flap breast reconstruction.

BACKGROUND: Contralateral breast augmentation during unilateral breast reconstruction is a good option for women with small breasts. In patients with adequate lower abdominal tissues, the deep inferior epigastric perforator (DIEP) flap is often the first choice for unilateral autologous breast reconstruction. We use Zone IV, which is usually excised owing to its insufficient blood circulation, as a superficial inferior epigastric artery (SIEA) flap for contralateral breast augmentation. METHODS: Between October 2004 and January 2016, 32 patients underwent unilateral breast reconstruction using a DIEP flap and an attempted simultaneous contralateral breast augmentation with an SIEA flap. The unilateral DIEP flap attached to the contralateral SIEA flap was split into two separate flaps after indocyanine green angiography. In all patients, ipsilateral internal mammary vessels were used as recipient vessels for DIEP flap breast reconstruction. The SIEA flap pedicle was anastomosed to several branches of the deep inferior epigastric vessels. The SIEA flap was inset beneath the contralateral breast through the midline. RESULTS: Of 32 patients, 27 underwent DIEP flap breast reconstruction and simultaneous unaffected breast augmentation using 25 SIEA or 2 superficial circumflex iliac artery perforator (SCIP) flaps. All DIEP flaps survived, and total necrosis occurred in one SIEA flap. The mean weight of the final inset for DIEP flap reconstruction and SIEA or SCIP flap augmentation was 416 g and 112 g, respectively. CONCLUSIONS: Unilateral DIEP flap breast reconstruction and contralateral SIEA flap breast augmentation may be safely performed with satisfactory results.

Pathological changes in the lymphatic system of patients with secondary upper limb lymphoedema.

Secondary upper limb lymphoedema is usually caused by lymphatic system dysfunction. Diagnosis is primarily based on clinical features. However, there are no distinct diagnostic criteria for lymphoedema. Although conventional lymphoscintigraphy is a useful technique to diagnose the severity of lymphoedema, the resultant data are two-dimensional. In this study, we examined the pathology of lymphoedema using single photon emission computed tomography-computed tomography lymphoscintigraphy (SPECT-CT LSG), a new technique that provides 3-dimensional information on lymph flow. We observed lymph flow pathways in the subcutaneous and muscle layers of the upper limbs. A significant positive correlation was found between the dermal back flow (DBF) type and the visualization of lymph nodes around the clavicle (p = 0.000266), the type of lymph flow pathways and the visualization of lymph nodes around the clavicle (p = 0.00963), and the DBF type and the lymph flow pathway (p = 0.00766). As the severity of lymphoedema increased, the DBF appeared more distally in the upper limb and the flow into the lymph nodes around the clavicle decreased, whereas the lymph flow pathways in the muscle layer became dominant. These findings demonstrate the features of lymphoedema pathology and the functional anatomy and physiology of the lymphatic system without the need for cadaver dissection.

Reduced skin lipid content in obese Japanese women mediated by decreased expression of rate-limiting lipogenic enzymes.

Skin barrier function is often deficient in obese individuals, but the underlying molecular mechanisms remain unclear. This study investigated how skin structure and lipid metabolism, factors strongly associated with barrier function, differed among 50 Japanese women of greatly varying body mass index (BMI). Subjects receiving breast reconstruction surgery were chosen for analysis to obtain skin samples from the same site. The subjects were classified into two groups, control (BMI < 25 kg/m2) and obese (25 kg/m2 ≤ BMI < 35 kg/m2), according to standards in Japan. Hematoxylin and eosin staining was used to assess skin thickness, Ki-67 immunostaining to examine keratinocyte proliferation, and real-time polymerase chain reaction to measure skin expression levels of genes associated with lipid metabolism. Total lipids, cholesterol, and fatty acids were also measured from these same skin samples. In the obese group, structural changes included epidermal thickening and an increase in the number of Ki-67-positive (proliferating) cells. Both skin cholesterol and fatty acid levels exhibited an "inverted-U" relationship with BMI, suggesting that there is an optimal BMI for peak lipid content and barrier function. Decreased lipid levels at higher BMI were accompanied by downregulated expression of PPARδ and other genes related to lipid metabolism, including those encoding acetyl-CoA carboxylase and HMG-CoA reductase, the rate-limiting enzymes for fatty acid and cholesterol synthesis, respectively. Thus, elevated BMI may lead to deficient skin barrier function by suppressing local lipid synthesis.