Age-related changes in the fiber structure around adipocytes in the subcutaneous fat layer and their association with skin viscoelasticity.

OBJECTIVE: Age-related changes in the fiber structure around adipocytes were investigated via scanning electron microscopy (SEM) of excised skin tissues. In addition, the viscoelasticity of the subcutaneous fat layer was evaluated via elastography, and the association between the fiber structure and the viscoelastic properties was assessed. METHODS: Skin tissues excised from the facial cheek area were used. Then, SEM images of these tissues were obtained. The thickness and quantity of the fibers around adipocytes were assessed using a 5-point scale. The score was used to grade 18 tissue samples. Moreover, the viscoelasticity of the subcutaneous fat layer in the same samples was evaluated via ultrasound elastography. RESULTS: Based on the SEM image score, an association was observed between the fiber status score and age, thereby indicating a tendency toward age-related fibrosis. Fiber structures with high scores, which indicate fibrosis, had a significantly lower viscoelasticity based on ultrasound elastography. CONCLUSION: The thickness and quantity of fibrous structures around adipocytes in the subcutaneous fat layer increase with age, and these changes can be associated with decreased viscoelasticity in the subcutaneous fat layer.

An exploratory study of structural and microvascular changes in the skin following electrical shaving using optical coherence topography.

BACKGROUND: Consumer products such as electrical shavers exert a combination of dynamic loading in the form of pressure and shear on the skin. This mechanical stimulus can lead to discomfort and skin tissue responses characterised as "Skin Sensitivity". To minimise discomfort following shaving, there is a need to establish specific stimulus-response relationships using advanced tools such as optical coherence tomography (OCT). OBJECTIVE: To explore the spatial and temporal changes in skin morphology and microvascular function following an electrical shaving stimulus. METHODS: Ten healthy male volunteers were recruited. The study included a 60-s electrical shaving stimulus on the forearm, cheek and neck. Skin parameters were recorded at baseline, 20 min post stimulus and 24 h post stimulus. Structural and dynamic skin parameters were estimated using OCT, while transepidermal water loss (TEWL) was recorded to provide reference values for skin barrier function. RESULTS: At baseline, six of the eight parameters revealed statistically significant differences between the forearm and the facial sites, while only surface roughness (Rq) and reflectivity were statistically different (p < 0.05) between the cheek and neck. At 20 min post shaving, there was a significant increase in the TEWL values accompanied by increased blood perfusion, with varying magnitude of change dependent on the anatomical site. Recovery characteristics were observed 24 h post stimulus with most parameters returning to basal values, highlighting the transient influence of the stimulus. CONCLUSIONS: OCT parameters revealed spatial and temporal differences in the skin tissue response to electrical shaving. This approach could inform shaver design and prevent skin sensitivity.

Post-Treatment Displacement of Facial Soft Tissue Fillers-A Retrospective Ultrasound-based Investigation of 382 Zygomatic Regions.

BACKGROUND: Clinical and ultrasound experience has revealed that after soft tissue injections of the lateral cheek, the filler may displace from the zygoma to the caudal temporal area. OBJECTIVE: To obtain more data to provide insight into product distribution when soft tissue fillers are injected in the zygomatic region. METHODS: Two hundred patients were examined with facial ultrasound imaging of the zygomatic and temporal region. Inclusion criteria were simply a positive response on the screening questionnaire as to whether or not they had filler injections placed in their lateral cheek. Control injections were also performed to the zygomatic regions of a body donor and in 10 patients ultrasound-guided. RESULTS: A correlation was found between the layers in which filler was detected on the zygoma and where it was ultimately found in the temples. Four different redistribution patterns were observed: (1) migration of filler within the superficial muscular aponeurotic system (SMAS) on the zygoma into the superficial temporal fascia. Migration of filler from the lateral suborbicularis oculi fat to (2) the deep interfacial plane of the temple or (3) to the superficial temporal fat pad; (4) migration from the supraperiosteal layer of the zygoma to the superficial temporal fat pad. Body donor and patients: filler deposits injected on the zygoma were witnessed to shift during injection into the caudal part of the temple. CONCLUSION: Soft tissue filler aliquots may be redistributed into the temples after injections of the lateral side of the zygomatic arch. The displacement follows a distinct pattern depending on the initial layer of injection.

Volume Redistribution of the Buccal Fat Pad After Reduction Malarplasty.

BACKGROUND: During reduction malarplasty, cheek bulging could be found immediately after zygomatic complex is moved inwards, backwards and upwards. As patient is in the supine position during surgery, the effect of gravity is eliminated, so the only reason for the bulge is the redistribution of the soft tissue in the deep facial spaces. The buccal fat pad, with its main body behind the zygomatic arch and buccal extension in the cheek area, is most likely to be responsible for the bulge. METHODS: 3D buccal extension models were reconstructed from preoperative and long-term follow-up CT images and the volume measured. By comparing the pre- and postoperative 3D models, the shape deviation of the buccal extension and facial soft tissue can be identified. RESULTS: Eleven patients (22 buccal extensions) met the inclusion criteria. Compared with the preoperative buccal extension volume, the postoperative volume increased significantly. By comparing the reconstructed models, the buccal extension volume increase with anteroinferior protrusion can be visually detected, and cheek bulging was clearly identified on the lower face. The bulging area coincided with the projection of the buccal extension on the skin surface. CONCLUSIONS: Reduction malarplasty may cause volume redistribution of the buccal fat pad. Therefore, preoperative assessment of the size of the buccal fat pad based on CT images is recommended. The buccal extension volume increase with anteroinferior protrusion is an important cause of postoperative cheek bulging and should be considered during treatment. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

Analysis of Anatomy and Age-related Changes in Infraorbital Cheek Using Computed Tomography.

BACKGROUND: There is no consensus regarding age-related facial anatomical changes. In this study, aging-related changes in soft and hard cheek tissues were quantitatively analyzed using computed tomography. METHODS: We performed a retrospective study of 90 Asian females who underwent facial computed tomography. Three-dimensional model of soft tissue in apple zone was reconstructed, and age-related changes in fat volume and pyriform aperture area were quantified using Mimics software. RESULTS: The apple zone is an aesthetic unit of the infraorbital cheek, with soft tissue located between the lateral wall of the pyriform aperture and the zygomatic major muscle. The superficial fat volume significantly decreased with age (P < 0.05). In contrast, a significant decrease in total fat volume was only observed between the young and old groups (P < 0.05). In linear regression modeling, age was a significant predictor of pyriform aperture area (R2 = 0.194, P < 0.001). CONCLUSIONS: These results suggest that superficial fat atrophy and bone remodeling in the cheek with age, and both of which combine to contribute to an aging facial appearance. LEVEL OF EVIDENCE IV: This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The influence of different cheek and lip retractors and emissivity on intraoral infrared thermography.

OBJECTIVES: To assess the influence of two conventional and one adapted cheek and lip retractors and three emissivity setting values on intraoral infrared thermography (IT) temperature values. METHODS: The sample was composed by 50 volunteers. Three cheek and lip retractors were tested: Group 1-flex retractor (FR); Group 2-FR adapted with Styrofoam; Group 3-U-type retractor (UR) for cheek and lip. All thermograms were acquired using FLIR T650 infrared camera. A set of three thermograms in frontal norm were acquired for each lip and cheek retractor at 0.91, 0.96, and 0.98ε, with an interval of 15 min between each set of images to avoid thermal interference. All images were assessed by two observers. The ROIs' mean temperature of the four upper incisors was recorded. Two-way ANOVA and Sidak post-test were used for data assessment with a significance level of 5%. RESULTS: Group 3 showed higher mean temperature than Groups 1 and 2 at all emissivity settings for all assessed teeth (P < .05). 0.91ε showed higher temperature than 0.96ε and 0.98ε for all assessed variables (P < .01). Contralateral teeth assessed using Group 3 at 0.91ε showed statistical differences between each other (P < .05). No statistical difference was observed between contralateral teeth assessed using Groups 1 and 2 at 0.96ε and 0.98ε (P > .05). CONCLUSIONS: The choice of cheek and lip retractor and emissivity setting can interfere on intraoral IT temperature values. U-type cheek and lip retractor and 0.91ε setting should not be used for IT image acquisition when assessing dental tissues.

Ultrasonography in the Assessment of Tumors of the Cheek: Water Mouth Distension Technique.

PURPOSE: To describe a new B-mode ultrasound examination technique to assess cheek tumors. MATERIALS AND METHODS: 30 cheek oral cavity lesions of different histological types (11 benign and 19 malignant) from 23 patients (11 women and 12 men, 7-82 years old, mean age of 49.5 years) were analyzed. Transcutaneous oral B-mode ultrasound (5-12 MHz transducer) was carried out in two stages. Initially it was performed conventionally with an empty mouth. Next, the patient was asked to keep their oral cavity filled with water (like when using a mouthwash) during imaging for the new test examination technique. The anatomical layers of this region and the characteristics of the tumors were evaluated. Lesions were classified as ill defined, partially defined, or defined. Conventional findings were compared to those of the new technique using the Wilcoxon signed-rank test. Ultrasound results were compared to histological findings analyzed by an independent team. RESULTS: The conventional empty mouth technique was able to confidently define lesion extension in only 6 of the 30 lesions, while the water-filled mouth technique was able to confidently define lesion extension in 29 of the 30 lesions (p<0.00001). CONCLUSION: We present a novel technique that dramatically improves ultrasound staging of cheek oral cavity tumors. In addition to the increase in ultrasound accuracy, this technique does not require any special equipment or extra cost, is very well tolerated by patients, and thus should be considered in the evaluation of every patient undergoing transcutaneous cheek ultrasound for oral cavity lesion characterization.

Fat infiltration into dermal layer induces aged facial appearance by decreasing dermal elasticity.

BACKGROUND: Facial morphology changes with aging, producing an aged appearance, but the mechanisms involved are not fully established. We recently showed that subcutaneous fat infiltrates into the dermal layer with aging, but it is not yet clear whether and how this drastic change of the dermal layer influences facial appearance. PURPOSE: We aimed to establish the role of fat infiltration in producing an aged facial appearance and to clarify the mechanism involved. METHODS: We analyzed the severity of fat infiltration in cheek skin of 30 middle-aged female volunteers by means of ultrasonography. Severity of the nasolabial fold, an established age-related morphology, was evaluated based on our photographic grading criteria as a measure of aged appearance. Skin elasticity was measured with a Cutometer. RESULTS: Fat infiltration to the dermal layer was detected at the cheek skin noninvasively by means of ultrasonography. Fat infiltration severity, measured as the minimum depth of the fat inside the dermal layer from the skin surface, was positively correlated with the magnitude of the nasolabial fold. Further, fat infiltration severity was significantly negatively correlated with dermal elasticity. CONCLUSIONS: Our results suggest that fat infiltration into the dermal layer is a critical factor inducing aged appearance of the face. The infiltrated fat decreases the dermal elasticity, which exacerbates nasolabial folds, namely producing an aged facial appearance.

The Importance of Ultrasound in Excision of the Buccal Fat Pad.

Partial excision of the buccal fat pad is a surgery indicated for different functional and aesthetic procedures. Although this surgery offers minimal risks, the ultrasound examination can provide security in performing the surgery, in addition to predicting preoperative anatomical variations and assisting in the treatment of postoperative complications. With the worldwide search for aesthetic procedures, concomitant with the development of imaging tests that help in different diagnoses and treatments, ultrasonography has become an excellent indication for planning oral fat pad surgeries.Level of Evidence V This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266 .

The facultative human oral pathogen Prevotella histicola in equine cheek tooth apical/ periapical infection: a case report.

BACKGROUND: Prevotella histicola is a facultative oral pathogen that under certain conditions causes pathologies such as caries and periodontitis in humans. Prevotella spp. also colonize the oral cavity of horses and can cause disease, but P. histicola has not yet been identified. CASE PRESENTATION: A 12-year-old Tinker mare was referred to the clinic for persistent, malodorous purulent nasal discharge and quidding. Conservative antibiotic (penicillin), antiphlogistic (meloxicam), and mucolytic (dembrexine-hydrochloride) treatment prior to referral was unsuccessful and symptoms worsened. Oral examination, radiography, sino-/ rhinoscopy, and standing computed tomography revealed severe apical/ periapical infection of the upper cheek tooth 209 with accompanying unilateral sinonasal inflammation and conchal necrosis. The tooth exhibited extensive subocclusal mesial infundibular cemental hypoplasia and caries, and an occlusal fissure fracture. After mechanical debridement and thermoplastic resin filling of the spacious subocclusal carious infundibular lesion, the tooth was extracted intraorally. The sinusitis and conchal necrosis were treated transendoscopically. Selective bacteriological swab cultures of affected tooth roots and subsequent matrix-assisted laser desorption ionization-time of flight mass spectrometry showed an infection with the obligate anaerobic, Gram-negative bacterium P. histicola. Surgical intervention and adapted antibiotic therapy led to normal healing without complications. CONCLUSIONS: This study provides the first documented case of dental infection in a horse caused by P. histicola at once indicating necessity of more sufficient microbiological diagnostics and targeted antibiotic treatment in equine dental practice. This finding is also conducive to understand species-specific Prevotella diversity and cross-species distribution.

Open-source, cost-effective, portable, 3D-printed digital lensless holographic microscope.

In this work, the design, construction, and testing of the most cost-effective digital lensless holographic microscope to date are presented. The architecture of digital lensless holographic microscopy (DLHM) is built by means of a 3D-printed setup and utilizing off-the-shelf materials to produce a DLHM microscope costing US$52.82. For the processing of the recorded in-line holograms, an open-source software specifically developed to process this type of recordings is utilized. The presented DLHM setup has all the degrees of freedom needed to achieve different fields of view, levels of spatial resolution, and 2D scanning of the sample. The feasibility of the presented platform is tested by imaging non-bio and bio samples; the resolution test targets, a section of the head of a Drosophila melanogaster fly, red blood cells, and cheek cells are imaged on the built microscope.

Validation of the elastic angle for quantitative and visible evaluation of skin elasticity in vivo.

BACKGROUND: Reduction in skin elasticity due to aging causes skin sagging and wrinkles. Although there are various objective and reliable techniques for measuring skin elasticity, it is difficult to obtain a visual representation of skin elasticity with them. Therefore, we developed a novel device, the Swing anglemeter, and analyzed its effectiveness for measuring skin elasticity of the cheek. MATERIALS AND METHODS: Forty-five healthy Korean women (age, 23-60 years) participated. The Swing anglemeter works by dropping a rubber ball on a subject's cheek, which draws a curve as it collides with the cheek. After recording the movement of the ball using the slow-motion function on a mobile phone, we defined the maximum angle at which the ball bounces off the skin as the elastic angle, using frame-by-frame video analysis. Changes in the elastic angle were assessed according to age, and correlation with the Ballistometer® results (Dia-stron Ltd., Andover, UK) was analyzed for validation. RESULTS: Elastic angles differed significantly (P < .001) according to age. A negative correlation was found between the elastic angle and age (r = -.799, P < .001). Compared with the Ballistometer® measurements, the elastic angle was negatively correlated with alpha (r = -.570, P < .001); it was positively correlated with the mean coefficient of restitution and area (r = .602, P < .001 and r = .535, P < .001, respectively). CONCLUSION: The elastic angle is a useful parameter for reflecting skin elasticity, both quantitatively and visually. Our method can help subjects understand their skin elasticity status. Therefore, we expect the device will be utilized in various fields within the cosmetic industry.

Anatomic Characteristics and Treatment of the Midcheek Groove by Deep Filling.

BACKGROUND: Because the anatomic mechanisms underlying the formation of the midcheek groove are unclear, treatments to date have resulted in unsatisfactory outcomes. OBJECTIVE: This study investigated the anatomical foundation of the midcheek groove and evaluated appropriate treatment methods. MATERIALS AND METHODS: Six cadaver hemifacial specimens were subjected to gross anatomic dissection and 6 to P45 sheet plastination. Based on the anatomic results, the area under the orbicularis oculi muscle (OOM) was selected for deep filling. Patients were evaluated by measuring 3D depth, regrading, and self-assessment. RESULTS: The medial band was observed to be an important structure of the OOM, with the facial projection overlapping the midcheek groove trace. Two of the 6 P45 specimens were found to have compact fibroelastic bundles (CFBs) between the medial band and the dermis. Deep filling of the area under the OOM significantly reduced the depth of each section in all 34 patients (p < .001). Grades 3 and 4 midcheek grooves were downgraded distinctively. Most subjects expressed satisfaction with outcomes. CONCLUSION: Formation of the midcheek groove is associated with the passage of CFBs. Deep filling of the area under the OOM effectively improves the midcheek grooves.

Quantitative evaluation of atrophic acne scars using 3D image analysis with reflected LED light.

BACKGROUND: Methods for objective evaluation of acne scars have not been established yet. In this study, the capability of three-dimensional image analysis of acne scarring was examined. METHODS: Two dermatologists evaluated the severity and counted the number of atrophic acne scars in a defined evaluation area of each cheek (3.5 cm × 3.5 cm) of 22 subjects (age, 21-38 years). Images of the evaluation area were obtained with an Antera 3D® (Miravex Limited, Ireland) camera three times, and three parameters (affected area, volume, and max depth) were measured. Three different filters (small, medium, and large), which limit measurement targets based on the diameters of concavities, were used for measurement. The relationships between each parameter and the evaluation results of scars by dermatologists were analyzed using Spearman's correlation coefficients. RESULTS: The correlations between the evaluation results of scars by dermatologists and each parameter measured were the highest when the large filter was used. The correlation coefficients between the severity of scars by dermatologists and each of affected area, volume, and max depth were 0.736, 0.728, and 0.722, respectively, and those between scar counts and each of affected area and volume were 0.783 and 0.770, respectively. The correlations, scatter plots, and regression lines among three measurements of parameters suggested high repeatability. CONCLUSIONS: Three-dimensional image analysis has the capability to evaluate changes in the shape of scars before and after treatment quantitatively.

Vertical Midface Lifting: An Improved Technique for Asians.

BACKGROUND: Treatment of the aging midface is increasingly deemed a key part of facial and periorbital rejuvenation. Compared with Westerners, Asians tend to have a relatively prominent zygoma and mandibular angle, thicker dermis, and greater propensity for scar formation. OBJECTIVE: This study was performed to review our surgical method of vertical midface lifting in Asian patients and evaluate the clinical outcomes. METHODS AND MATERIALS: This retrospective observational study involved 116 Asian women who complained of an aged midface. All patients underwent midface rejuvenation surgery with one lower eyelid incision and 2 small frontal-temporal incisions. Clinical results were assessed objectively using photographs and subjectively by a patient satisfaction survey. RESULTS: All patients recovered well without major complications. High patient satisfaction (94%) was attained. The improvement scores as evaluated by the panel demonstrated a higher level of improvement for the malar eminence (8.3 ± 0.6), nasojugal groove (8.0 ± 0.8), and nasolabial fold (7.9 ± 0.7) than for the lower face (6.2 ± 1.0). CONCLUSION: Our vertical midface lift technique is safe and effective for older Asian patients with a midface aging appearance. LEVEL OF EVIDENCE: Therapeutic IV.

Filler Migration and Florid Granulomatous Reaction to Hyaluronic Acid Mimicking a Buccal Tumor.

Hyaluronic acid is among the most commonly used cosmetic fillers. Although considered biocompatible and safe, it may rarely cause a wide range of complications. The authors report a case of migration of hyaluronic acid concomitant with granulomatous inflammatory response that mimicked a buccal tumor. A 52-year-old female presented with a solid painless mass of the right buccal area. The patient denied any history of trauma and cosmetic procedures of the affected area. Skin and mucosal membrane were intact and the lesion was firm and well fixed in the deep plane. Due to worrisome clinical presentation and the patient's history of breast cancer, the lesion was excised radically. Histopathological examination revealed multiple granulomas surrounding amorphous lakes of hyaluronic acid. During repeated, thorough anamnesis the patient admitted having underwent lip augmentation and nasolabial fold correction with HA two years before, after which the filler must have migrated posteriorly. Physicians need to be aware of various complications associated with cosmetic fillers as they may mimic severe clinical conditions.

Deep Cheek Fat Volumes and Midfacial Aging.

BACKGROUND: Midfacial volumizing procedures are increasingly common in facial rejuvenation. However, the changes that occur in midfacial fat with aging are poorly understood. OBJECTIVES: The aim of this study was to determine how deep cheek fat volume is predicted by age. METHODS: We conducted retrospective cross-sectional and longitudinal studies of patients based on facial computed tomography (CT) scans. In the cross-sectional cohort, multiple linear regression analysis was performed to model the relations between age and deep cheek fat volumes. In the longitudinal analysis, changes to deep cheek fat volumes were tracked among subjects who underwent multiple facial CT scans. RESULTS: The cross-sectional cohort comprised 109 patients. The mean (SD) age of the subjects was 59.7 (15.0) years (range, 21.7-91.1 years). A linear regression analysis showed that increasing age was associated with increasing deep cheek fat volume (ß = 0.015, P < 0.001). Additional regression analyses showed that the gain of fat with aging was more pronounced in the caudal aspect of the cheek (ß = 0.007, P < 0.001) than in the cephalad (ß = 0.005, P < 0.001). Twenty-three subjects were identified for longitudinal analysis. The mean (SD) ages at initial and final imaging time points were 50.0 (5.8) and 60.3 (5.2) years. In the deep fat compartment, there was an average gain of 0.23 mL over 10.3 years (P = 0.03). CONCLUSIONS: Age is an important predictor of midfacial deep cheek fat volume. In this study, there is no evidence of adipose volume loss in the deep cheek compartment. Rather, aging was associated with an increase in deep cheek fat, possibly reflecting pseudoherniation of buccal fat.

Use of Raman spectroscopy in the assessment of skin after CO2 ablative fractional laser surgery on acne scars.

BACKGROUND: Ablative fractional laser surgery is a common technique for treating acne scars. However, an in vivo and noninvasive analysis of the histologic variations between acne skin and the resulting resurfaced skin is needed in order to evaluate the wound healing process of the scars induced by the ablative fractional laser surgery. MATERIALS AND METHODS: Nine patients with acne scars underwent a single treatment with a CO2 ablative fractional laser surgery. Collagen presence on the resurfaced skin was noninvasively assessed by means of Raman spectroscopy and principal component analysis. RESULTS: Principal component analysis shows that all the patients presented a collagen regeneration on the resurfaced skin after the laser treatment. CONCLUSION: Collagen plays a crucial role in the wound healing process. By assessing the collagen presence on the skin, it was possible to quantify the regenerative effects of the ablative fractional laser in a noninvasive way.

Age estimation based on visual parameters of the skin of cadavers.

BACKGROUND: Previous studies have reported relationships between various visual parameters of the skin and changes due to aging. Due to an increase in the discovery of unidentified bodies, the field of forensic medicine anticipates the development of a rapid method for estimating age. The present study measured various visual parameters of the skin in human remains and investigated the correlation between these parameters and age. MATERIALS AND METHODS: Skin images were taken of four body parts (cheek, chin, brachium, and thigh) of 414 forensic cases. We interpreted eight visual parameters of the skin (smoothness, roughness, texture, dullness, brightness, erythema, color phase, and sagging) from skin photograph images, and constructed three age-prediction models, categorized by sex, postmortem interval, and age. RESULTS: Significant correlations were observed in the erythema of the cheek and chin, the roughness of the brachium, and the texture of the brachium and thigh among the visual parameters calculated in four body parts, using the three models. The root-mean-square errors, which indicate the precision of the three prediction models, were 13.06, 13.80, and 13.77. The only model that demonstrated a correlation with the visual parameters was sex (but not age or postmortem interval). CONCLUSION: Similar to living subjects, we observed a correlation with age for a number of visual parameters. The parameters that correlate with age depend on whether the site being measured was exposed to sunlight. Age estimation based on visual parameters requires measurement of visual parameters for skin both exposed and not exposed to sunlight.

Indocyanine Green Sentinel Node in Merkel Cell Carcinoma of the Cheek.

Merkel cell carcinoma (MCC) is a rare malignant tumor with a neuroendocrine phenotype. The authors report a case of MCC of the left cheek region in an 85-year-old Caucasian woman who also received sentinel node biopsy using both Technectium-99m-labeled (99mTc) lymphoscintigraphy and indocyanine green lymphography.