Skin Contour Research Articles

Optical Automatic Contour Tracing (O-ACT) - A novel optical image-guided contour tracing method for electron beam shaping.

Electron therapy, vital for treating skin lesions and superficial tumors, demands precise electron cutouts to ensure accurate dose delivery. Traditional manual tracing methods introduce uncertainties and inefficiencies, necessitating innovative solutions for custom block creation. To introduce and validate the Optical Automatic Contour Tracing (O-ACT) method, enhancing electron cutout generation's accuracy and efficiency through optical imaging and software automation. Utilizing a 3D-printed holder, a centrally-mounted charge-coupled device (CCD) camera on the electron applicator secured two distinct perspective images of the skin's contour at varying heights. Through image binarization and skeletonization, we identified the clinical target contour's region-of-interests (ROIs) in each setup image. Employing distances from each ROI's center, assessed at 5-degree intervals from both images, we reconstructed the target contour on the skin. The magnification factor, set at a 95cm source-to-point distance, determined the final cutout shape. We crafted an in-house software in MATLAB for camera calibration and image processing and juxtaposed our results against the standard clinical cutout from the treatment planning system (TPS) using a correlation coefficient based on masked binary images' mutual information. Additionally, we performed dosimetric evaluations using abstract shapes to compare O-ACT with other methods. Our methodology yielded cutout shapes exhibiting remarkable alignment with the TPS clinical cutout. O-ACT demonstrated superior precision in generating cutout shapes that closely align with the contours in TPS, improving upon other methods in terms of adaptability to patient body shapes and contour accuracy. Dosimetric evaluations showed minimal differences between methods, with O-ACT providing slightly more consistent results. Dose profile analyses in penumbra regions indicated O-ACT's improved accuracy compared to conventional methods. Pushing the boundaries of traditional practices, our O-ACT offers a more accurate, efficient, and reproducible method for custom electron cutout creation from clinical setup images. This innovation promises not only to streamline clinical workflow but also to potentially uplift clinical outcomes in radiation oncology by providing more accurate patient-specific treatment accessary.

A skin-mountable flexible biosensor based on Cu-MOF/PEDOT composites for sweat ascorbic acid monitoring

Continuous monitoring of sweat nutrients offers valuable insights into metabolic cycling and health levels. However, existing methods often lack adaptability and real-time capabilities. Here, we propose a skin-mountable flexible biosensor integrated with metal-organic framework (MOF)-derived composites for real-time monitoring of sweat ascorbic acid (AA) levels. The biosensor features a miniaturized, highly integrated system capable of an imperceptible, stretchable skin patch with dimensions of 16.9 × 9.9 × 0.1 mm3, ensuring conformal integration with curvilinear skin contours. The introduction of a copper-based MOF anchored with poly(3,4-ethylenedioxythiophene) (Cu-MOF/PEDOT) significantly enhances sensing performance toward AA, achieving a detection limit of 0.76 μM and a sensitivity of 725.7 μA/(mM·cm2). Moreover, a miniaturized flexible circuit enables wireless communication, resulting in a lightweight, wearable platform weighing only 1.3 g. Structural and electrochemical analyses confirm the favorable sensitivity, reversibility, and stability of the biosensor, while in-vivo validation in human subjects further reveals the capability to track sweat AA variations during nutrient intake and sustained exercise, showcasing its potential in metabolic cycle assessment and health management. The biosensor presents a promising avenue for scalable health monitoring using adaptable and user-friendly technologies.

Cross‐Institutional Prediction System for Estimating Patient‐Specific Organ Dose from Chest CT Scans without Segmenting Internal Organs

This study aims to establish and validate a cross‐institutional prediction system for estimating patient‐specific organ doses from chest CT scans. By collaborating across multiple institutions, the study seeks to develop models that allow rapid online estimation of organ doses, eliminating the need for complex organ segmentation. Researchers delineate skin outlines from chest CT images obtained from two different institutions. Radiomics features are extracted from the chest CT data and skin contours. Organ doses are computed using Monte Carlo simulations as reference organ doses. Single‐ and cross‐institutional support vector regression (SVR) models are trained with radiomics features to predict organ doses from chest CT scans. Model performance is assessed using metrics like maean absolute percentage error (MAPE) and R‐squared (R2). For chest organs (lungs, heart, spinal cord, trachea, and esophagus), single‐institutional SVR models achieve MAPE values ranging from 4.72% to 15.31% and R2 values from 0.73 to 0.93. Cross‐institutional models have MAPE values in the range of 2.16–7.49% and R2 values from 0.84 to 0.99. SVR models trained with radiomics features from skin outlines can reliably estimate organ doses from chest CT scans. The proposed method is applicable across different institutions, and cross‐institutional models enhance predictive accuracy, generality, and robustness.

From Phantoms to Patients: Improved Fusion and Voxel-Wise Analysis of Diffusion-Weighted Imaging and FDG-Positron Emission Tomography in Positron Emission Tomography/Magnetic Resonance Imaging for Combined Metabolic-Diffusivity Index (cDMI).

Hybrid positron emission tomography/magnetic resonance imaging (PET/MR) opens new possibilities in multimodal multiparametric (m2p) image analyses. But even the simultaneous acquisition of positron emission tomography (PET) and magnetic resonance imaging (MRI) does not guarantee perfect voxel-by-voxel co-registration due to organs and distortions, especially in diffusion-weighted imaging (DWI), which would be, however, crucial to derive biologically meaningful information. Thus, our aim was to optimize fusion and voxel-wise analyses of DWI and standardized uptake values (SUVs) using a novel software for m2p analyses. Using research software, we evaluated the precision of image co-registration and voxel-wise analyses including the rigid and elastic 3D registration of DWI and [18F]-Fluorodeoxyglucose (FDG)-PET from an integrated PET/MR system. We analyzed DWI distortions with a volume-preserving constraint in three different 3D-printed phantom models. A total of 12 PET/MR-DWI clinical datasets (bronchial carcinoma patients) were referenced to the T1 weighted-DIXON sequence. Back mapping of scatterplots and voxel-wise registration was performed and compared to the non-optimized datasets. Fusion was rated using a 5-point Likert scale. Using the 3D-elastic co-registration algorithm, geometric shapes were restored in phantom measurements; the measured ADC values did not change significantly (F = 1.12, p = 0.34). Reader assessment showed a significant improvement in fusion precision for DWI and morphological landmarks in the 3D-registered datasets (4.3 ± 0.2 vs. 4.6 ± 0.2, p = 0.009). Most pronounced differences were noted for the chest wall (p = 0.006), tumor (p = 0.007), and skin contour (p = 0.014). Co-registration increased the number of plausible ADC and SUV combinations by 25%. The volume-preserving elastic 3D registration of DWI significantly improved the precision of fusion with anatomical sequences in phantom and clinical datasets. The research software allowed for a voxel-wise analysis and visualization of [18F]FDG-PET/MR data as a "combined diffusivity-metabolic index" (cDMI). The clinical value of the optimized PET/MR biomarker can thus be tested in future PET/MR studies.

Optimizing tumor treating fields for blood cancer therapy: Analysis of electric field distribution and dose density.

Blood cancer is a condition in which white blood cells grow uncontrollably. Tumor treating fields (TTF) are a modality of cancer treatment that utilizes electric fields to target malignant cells. To optimize the efficacy of TTF, it is necessary to investigate the distribution of electric field through varying electrode configurations and input parameters. This allows for enhancement of electric field intensity in targeted areas while minimizing intensity in sensitive areas. Analysis of electric field distribution was conducted through simulation of brachial models with varying electrode configurations and input parameters, utilizing the COMSOL Multiphysics 5.4 software. Additionally, investigations were carried out to assess tissue dose density. The dose density value at primary target for all electrode configurations and input parameters do not exceed the threshold value (770 W/m3), whereas the electric field value at the primary target satisfied the threshold value (100 V/m) on the system that used 4 plate-shaped electrodes and arm contour-shaped electrodes with an input voltage of 20 V, and at the input voltage 15 V, only 4 arm contour-shaped electrodes that satisfied the threshold value. An increase in input voltage, electrodes addition, and electrodes adjustment to skin contour shape result in an enhancement of electric field distribution and average electric field value at primary targets.

Management of complications following implant-based breast reconstruction: a narrative review.

Complications associated with implant-based reconstruction have a spectrum of severity with sequelae ranging from mild aesthetic deformities to additional surgery, reconstructive failure and systemic illness. The purpose of this narrative review of the literature is to provide updated evidence-based information on the management of complications in implant-based reconstruction. A systematic search of PubMed, OVID MEDLINE and the Cochrane Library databases was performed to identify common complications associated with implant-based breast reconstruction, incidences of occurrence as well as preventative and management strategies. Pertinent short and long-term complications of implant-based breast reconstruction include hematoma, implant infection, seroma, skin envelope necrosis, capsular contracture, rupture, malposition, animation and contour deformities, implant-associated anaplastic large cell lymphoma, and breast implant illness. Important preventative measures for short term complications include meticulous sterile technique and antibiotic irrigation, adequate drainage and critical evaluation of mastectomy flaps. Management of short-term complications requires early recognition and aggressive treatment to prevent reconstructive failure as well as long-term complications such as capsular contracture. Important technological advances include dual-port expanders for seroma drainage, indocyanine green angiography for mastectomy flap perfusion evaluation, cohesive form-stable implants for treatment of rippling, and various biologic and synthetic mesh products for pocket control and correction. Important principles in management of short-term complications in implant-based reconstruction include aggressive and early intervention to maximize the chance of reconstructive salvage. Contemporary technological advances have played an important role in both prevention and treatment of complications. Over-arching principles in management of implant-based reconstruction complications focus on preventative techniques and preoperative patient counseling on potential risks, their likelihood, and necessary treatments to allow for informed and shared decision-making.

An Investigation of High-Z Material for Bolus in Electron Beam Therapy

Electron beams are frequently used for superficial tumors including: primary skin cancers, surgical scars, cutaneous lymphomas and benign conditions like keloids. However, due to electron beam characteristics the surface dose is 75-95% of the prescribed dose depending on beam energy thus requiring placement of bolus to augment surface dose. Various types of boluses; wet gauge/towel, superflab, superstuff, aquaplast, 3D printed plastics, customized dot-decimal bolus, thermoshield, brass and tantalum wire mesh are commonly used in clinics with variable difficulties that are not perfect. As majority of these devices do not snug to the skin contour and create air-gap that is known to produce significant dose perturbations creating hot and cold spot. The variable dosimetry has cosmetic implications and potentially increased risk of recurrence. A new cloth-like high-Z materials; Tungsten, (Z = 74) and Bismuth, (Z = 83) impregnated with silicone gel are now commercially available which is investigated in this study for bolus purpose. Commercially available, super soft silicone-gel based submillimeter thin Tungsten and Bismuth sheets were investigated for bolus properties in electron beams in the range of 6-12 MeV using 10x10 cm2 applicator. These materials were tested on various body contour for perfect snug without any air traps. Using parallel plate ion chamber measurements were performed in a solid water phantom on a medical linear accelerator machine. Depth dose characteristics were measured to optimize the thickness for surface dose to be 100% for selected electron therapy. Surface dose for a 10x10 cm2 cone for 6, 9, 12 MeV beams were measured to be 75.1%, 80.1% and 86.2%, respectively. Silicone-gel Tungsten and Bismuth sheets produce significant electrons thus increasing surface dose. Based on measured depth dose, our data showed that Tungsten sheets of 0.14 mm, 0.18 mm and 0.2 mm and Bismuth sheets of 0.42 mm, 0.18 mm and 0.2 mm provide 100% surface dose for 6, 9 and 12 MeV beams, respectively without any changes in depth dose except increasing surface dose. The new Tungsten and Bismuth based silicone-gel clothlike sheets are extremely soft but high tensile metallic bolus materials that can fit flawlessly on any skin contour without any air trap or variable thickness or spillage of the water as in conventionally used wet gauge. Only 0.2 mm thick sheets are needed for 100% surface dose without degradation of the depth dose characteristics. These materials are reusable and ideal for bolus in electron beam treatment. This investigation opens a new frontier in designing new bolus materials optimum for patient treatment.

Dose Volume Thresholds Associated with Acute Skin Toxicities in Proton Beam Therapy

The depth-dose characteristics of proton beam therapy (PBT) mean that the skin-sparing effect is reduced with PBT, potentially leading to an increased incidence and severity of acute radiotherapy induced skin toxicities (RIST). Predictive factors of acute RIST in patients treated with PBT remain largely undefined. In this study, we retrospectively reviewed the acute RIST of patients treated with pencil beam scanning (PBS) PBT to identify dose-volume thresholds which are predictive of acute RIST. All patients treated with PBS-PBT at a single institution between December 2018-October 2022 were included in this study. Acute RIST were recorded as per RTOG grading scale and dichotomized to Grade (G) <2 vs ≥2. Anonymized demographics, clinical and dosimetric data were extracted from electronic patient records and a treatment planning system. Skin structure is defined as 5mm rind grown as an inner margin from the patient contour. The following skin dose-volume statistics were collected: Dmax (maximum dose to any pixel inside the skin contour) and dose to skin volumes in 5Gy increments (V5Gy, V10Gy etc.). Preliminary analyses of dosimetric data of patients with G0, G1 vs ≥G2 acute RIST are presented, with significance assessed at the 5% level using t-tests and univariate logistic regression models, and risk thresholds determined using receiver operating characteristic (ROC) curves. We report the data for 582 patients with extracted dosimetric data. The pediatric, teenage and young adult (TYA) and adult populations were 38%, 19% and 43% respectively. The three most common indications for PBT were head and neck cancers (HNC) (23%), sarcoma (21%), and chordoma (15%). Increasing age, HNC and sarcoma were associated with an increased risk of grade 2+ acute RIST. For patients who developed acute RIST of G2+, the median volume receiving 10Gy, 20Gy, 30Gy, 40Gy and 50Gy were significantly higher (P<0.0001) than patients with G0 and G1. The dose volume effect of acute RIST is greater at 30Gy and above. Similarly, median Dmax was significantly higher in the G2+ acute RIST group compared to G0 and G1 (P<0.0001) for all age groups. Using the ROC curve, we observed threshold volumes (in cm3) for V10Gy, V20Gy, V30Gy, V40Gy and V50Gy (Table 1). The volume of irradiated skin and Dmax are associated with the risk of developing acute RIST in patients treated with PBS PBT. Further work is being done to develop a model predictive of acute RIST in clinical setting.

Short-term efficacy of digitally-assisted traditional Chinese medicine manual reduction combined with 3D printed splint in the treatment of AO type-A distal radius fractures

Objective To explore the short-term efficacy of digitally-assisted traditional Chinese medicine manual reduction combined with 3D printed splint in the treatment of AO type-A distal radius fractures, and explore the quantification of traditional Chinese medicine manual reduction and personalized improvement of splinting. Methods The clinical data of 50 patients with AO type-A distal radius fractures, who received treatment at the outpatient department of Cangzhou Integrated Traditional Chinese and Western Medicine Hospital in Hebei Province, were retrospective analyzed. The patient cohort included 22 females and 28 males, with ages ranging from 25 to 75 years old. Among them, 27 cases presented with distal radius fractures on the left side, and 24 cases on the right side. The patients were categorized into two groups: treatment group (n=25) and control group(n=25). There were 13 males and 12 females in the treatment group, with an average age of (56.2±5.5) years old. Treatment approach for this group involved several steps. Initially, Mimics Research software was used to conduct comprehensive analysis of complete CT data from the affected limb, resulting in the creation of a three-dimensional model. Subsequently, 3D models of the bones and skin contours, stored as STL format files, were imported into the Materialise Magics 23.0 software for model processing and repair. This facilitated the simulation of reduction and recording of displacement data, effectively generating a "digital prescription" to guide and quantify traditional Chinese medicine manipulation procedures. Finally, a personalized 3D printed splint was applied for fixation treatment. There were 15 males and 10 females in the control group, with an average age of (53.32±5.28) years old. These patients were treated with manualreduction combined with traditional splinting. The clinical efficacy of the two groups was assessed in terms of fracture reduction quality, fracture healing time, Gartland-Werley wrist joint score and X-ray parameters (palminclination angle, ulnar deviation angle, radius height) at 6 weeks post-operatively. Results The treatment group exhibited a shorter duration for achieving clinical healing compared to the control group (P<0.05). Six weeks post-operatively, the treatment group demonstrated higher wrist joint function scores, and a higher proportion of excellent and good outcomes than the control group(P<0.05). The treatment group was superior to the control group in terms of imaging parameters 6 weeks post-operatively (P<0.05). Conclusion By quantifying skin contours through digital simulation prescription reduction, a personalized 3D printed splint is developed to effectively stabilize fractures, enhancing localized fixation while ensuring greater adherence, stability, and comfort. This innovative approach offers personalized treatment for AO type-A distal radius fractures and presents a novel, precise treatment strategy for consideration.

Contouring variation affects estimates of normal tissue complication probability for breast fibrosis after radiotherapy

BackgroundNormal tissue complication probability (NTCP) models can be useful to estimate the risk of fibrosis after breast-conserving surgery (BCS) and radiotherapy (RT) to the breast. However, they are subject to uncertainties. We present the impact of contouring variation on the prediction of fibrosis. Materials and methods280 breast cancer patients treated BCS-RT were included. Nine Clinical Target Volume (CTV) contours were created for each patient: i) CTV_crop (reference), cropped 5 mm from the skin and ii) CTV_skin, uncropped and including the skin, iii) segmenting the 95% isodose (Iso95%) and iv) 3 different auto-contouring atlases generating uncropped and cropped contours (Atlas_skin/Atlas_crop). To illustrate the impact of contour variation on NTCP estimates, we applied two equations predicting fibrosis grade ≥ 2 at 5 years, based on Lyman-Kutcher-Burman (LKB) and Relative Seriality (RS) models, respectively, to each contour. Differences were evaluated using repeated-measures ANOVA. For completeness, the association between observed fibrosis events and NTCP estimates was also evaluated using logistic regression. ResultsThere were minimal differences between contours when the same contouring approach was followed (cropped and uncropped). CTV_skin and Atlas_skin contours had lower NTCP estimates (−3.92%, IQR 4.00, p < 0.05) compared to CTV_crop. No significant difference was observed for Atlas_crop and Iso95% contours compared to CTV_crop. For the whole cohort, NTCP estimates varied between 5.3% and 49.5% (LKB) or 2.2% and 49.6% (RS) depending on the choice of contours. NTCP estimates for individual patients varied by up to a factor of 4. Estimates from “skin” contours showed higher agreement with observed events. ConclusionContour variations can lead to significantly different NTCP estimates for breast fibrosis, highlighting the importance of standardising breast contours before developing and/or applying NTCP models.

24. Improving Re-epithelization after Burn Injuries: The Role of Pixel-grafting and Wet Wound Healing

PURPOSE: Complex facial and extremity burns present a difficult challenge affecting skin contour, mobility, and appearance. Management requires consideration not only to the skin, but to a patient’s quality of life. Interventions often require stage-reconstruction, revision for increasingly unsatisfactory results and a burdensome dressing during healing. This standard is costly, limited by donor-site availability, and often morbid. Currently, there are no single-stage interventions with simple dressings to address complex, full thickness burns. Our team has formerly shown the advantage of adipose-first reconstruction. Here we aim to provide a complete approach by demonstrating the efficacy of single-staged minced skin grafting plus adipose in an incubator-like microenvironment with a platform wound device (PWD) to achieve rapid reconstruction after burns. METHODS: A customized burn device was used to induce sixteen standardized full-thickness burns on Female Yorkshire swine. Delayed escharectomies were performed to the level of fascia. One group received standard of care skin grafting with either bolster or PWD. In another group, autologous split-thickness skin was cut into pixel size (0.3x0.3 mm) grafts, combined with or without adipose, and followed by application of either bolster or PWD. Wounds were followed for 4-weeks with weekly photography, ultrasound, histology, and tension measurements. RESULTS: The PWDs provided an optimized environment and protected the wounds from graft displacement despite no limitations in mobility. As early as one week, epithelialization started in the pixel with PWD group with visible epithelioid islands on the wound bed granulation tissue. This progressed with a similar trend throughout the 4-week period eventually leading to near-complete epithelization and keratinization. Immunofluorescence staining demonstrated reconstruction of trilaminar cutaneous architecture and viability of adipose. Distinct differences in contour were noted between the bolster and PWD groups. CONCLUSION: In both the bolstered and moist PWD-environment, pixel-grafts survived to form a viable basal layer. Use of positive-pressure (bolster) vs. negative-pressure PWD demonstrated distinct differences in the convexity/concavity and topography of the single-stage skin graft with critical implications for aesthetic reconstruction. Additionally, minced grafting minimized donor burden and alleviated the need for graft orientation. This study demonstrates the efficacy of a single-staged approach and the use of a sustainable dressing that both provides enhanced reconstruction and decreased burden.

A Suture Tips Applied to Rotating Flaps in Reconstructing Facial Defects to Optimize Scarring: A Retrospective Study

Background: Local flap reconstruction is the most common method to repair facial defects. In this study, authors have explored and introduced a modified suture technique with rotation flap to repair facial defects that makes scarring more discreet and easier to perform. Methods: Patients with facial defects who underwent surgical treatment of the rotation flaps reconstructions and were admitted to our department between October 2014 and October 2019 were included in this retrospective study. The rotating flap is designed along the Relaxed Skin Tension Line (RSTLs) and contour lines, parts of patients received modified suture depending on the shape and size of the defect. Observe the flaps’ survival and complications. Assessments of the scars with Vancouver Scar Scale (VSS) regularly and follow-ups. Results: This five-year retrospective study evaluated a total of 56 patients; of these, 45 patients underwent modified suture surgery, the average defects were 19.7±4.5×25.5±5.2mm, and the average duration of follow-up was 13.8±5.0 months. Scar appearance was evaluated using the VSS score, range from 0-5, with an average of 1.6±1.1, and mainly reflected in pigmentation and vascularity. Postsurgical scar concealment is made afterward, and all flaps survive. No hemodynamic disorder or necrosis was found. Conclusion: The rotation flap was designed based on RSTLs/ contour lines to repair the facial defect and make the scarring well concealed. The modified suture method makes the flap line consistent with the RSTLs/ contour line of the facial skin to the maximum extent and leads to better facial aesthetics results.

Clinical evaluation of cylindrical regional suppression in dynamic contrast-enhanced breast MRI: An intra-individual comparison study on image quality and lesion conspicuity

PurposeTo evaluate the effect of a cylindrical regional-suppression technique (CREST) on image quality and lesion conspicuity in dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) of the breast. MethodThis was a comparative study of 67 women with 44 lesions who underwent breast DCE-MRI with CREST (CREST-DCE) and had a previous DCE-MRI without CREST (conv-DCE) available. Two radiologists assessed image quality parameters and lesion conspicuity using five-point Likert scales. In an intra-individual comparison, the effects of CREST on image quality (strong degradation to strong improvement) were assessed. Moreover, both radiologists identified the post-contrast phase, which benefited the most from using CREST in direct comparison. The statistical analysis included the Wilcoxon signed-rank test. ResultsCardiac motion-rated artefacts were significantly reduced in CREST-DCE compared to conv-DCE (3.6 ± 1.2 [CREST-DCE] vs 2.1 ± 0.8 [conv-DCE], p < 0.001). At the axilla, the visualisation of anatomical structures (3.9 ± 1.0 vs 2.3 ± 1.2, p < 0.001) and the skin contour (4.3 ± 0.8 vs 3.0 ± 1.1, p < 0.001) were significantly improved in CREST-DCE, whereas ghosting artefacts were significantly less pronounced (3.8 ± 1.1 vs 2.4 ± 1.0, p < 0.001). The parasternal region was similarly assessable using both techniques (4.3 ± 1.1 vs 4.2 ± 1.2, p = 0.47). In direct comparison, CREST-DCE images were classified as “improved” in 54/67 and “equivalent” in 13/67 exams. The effects of CREST were found to be most pronounced in the very early post-contrast phase (32/67). The lesion conspicuity was rated similar for CREST and conv-DCE (4.7 ± 0.7 vs 4.8 ± 0.2, p = 0.18). ConclusionsCREST appears to be an effective tool to reduce cardiac motion-related artefacts and, therefore, may improve image quality in breast DCE-MRI without impairing lesion conspicuity.

BEST (Bolster Equalization Suture Technique) Neck: Optimization of Skin Redraping Following Necklift Surgery.

Skin laxity of the neck is a primary concern of patients seeking facial rejuvenation. Traditional methods for redraping neck skin have well-described shortcomings. To optimize skin redraping after necklift surgery while reducing risk, the BEST (Bolster Equalization Suture Technique) was developed as described. At the conclusion of the facelift and necklift, 3 external quilting sutures are placed with protective bolsters. The first suture is placed at the midline, advancing the skin posteriorly toward the hyoid and anchoring the skin to the platysma. The second and third are placed in the cervicomandibular groove over the sternocleidomastoid muscle, advancing the skin posteriorly. Complications such as skin necrosis, skin ischemia, dimpling, hypopigmentation, hyperpigmentation, and scarring were documented. A control group of 20 patients who underwent the same surgery without the BEST was compared to the next 20 patients using the technique. Preoperative and postoperative photographs were blindly reviewed by two plastic surgeons. The photographs were analyzed for residual central neck skin laxity and cervicomental angle improvement and surveyed using the pertinent sections of the FACE-Q. In necklift patients who received the BEST, cervicomental angle improvement and decreased central skin laxity were statistically significant. Patient perceived age on the visual analogue scale was 2.5 years younger in the BEST group. The BEST is a safe and efficient method which can be used to improve cervical skin redraping and contour. The BEST creates a more defined cervicomental angle while reducing central skin neck laxity with minimal complications.

Skin Contour Sutures in Rhinoplasty.

The skin-soft tissue envelope (STE) is a critical component of rhinoplasty and can have a significant impact on the final result. Skin contour sutures (SCSs) can be used to prevent potential complications related to skin detachment and to improve rhinoplasty results. The aim of this study was to assess the efficiency of SCSs for nasal skin approximation. SCSs involve the use of external sutures to stabilize the STE flap based on the principle that the pressure of the sutures helps to approximate the STE to the underlying nasal skeleton. The first study group demonstrated the utilization of SCSs in 459 consecutive rhinoplasty cases between December 2016 and April 2022 which were retrospectively reviewed. The second study group consisted of 30 patients with thick skin who had insertion of SCSs with ultrasonic evaluation both preoperatively and postoperatively. The average postoperative follow-up period in the first study group was 41 months (range, 12-64 months). Any suture site that was visible after removal of the suture disappeared completely after 6 weeks in most patients. No complications were reported. In the second group the ultrasound data indicated that STE healing was faster as its thickness returns to its preoperative state earlier in the healing process when SCSs were used. SCSs appear to help to decrease severe nasal edema, hematomas, loss of tip definition, fibrosis, and pollybeak deformity, thereby improving the results and predictability of rhinoplasty surgery.

35320 Pilot evaluation of safety and efficacy in diverse skin types of a novel topical hyaluronidase-polysaccharide formulation for contour irregularities following filler injection

Injectable hyaluronidase is used off-label for skin contour irregularities, nodules or ischemia following hyaluronic acid (HA) fillers, and sometimes for non-HA filler nodules. However, hyaluronidase injections are associated with local allergic reactions (incidence 0.05-0.69% rising to 31.3% with 200,000 IU) and rare urticaria and angioedema (incidence < 0.1%). Availability and use of injectable hyaluronidase are limited by country-specific regulations, Some patients decline injections to address filler complications. After ethical board approval, 17 females aged 23 to 54 (six having skin phototypes IV-VI) with chronic post-filler contour irregularities received 1 to 3 topical treatments with a new formulation of hyaluronidase enzymatically complexed with botanical polysaccharides. Treated areas were infraorbital (10), lips (5), and malar festoons (2). Post-application massage was performed in office and at home. Two to 4 weeks after final treatment, physician-assessed contour improvement was 8-10/10 for 7 patients, 5-7/10 for 6, 1-4/10 for 3, and 0/10 for 1 patient. Fifteen patients evaluated their skin as more uniform (5/10 to 10/10). Satisfaction scores were 7-10/10 for 13 patients, 6/10 for 2, and 0-1/10 for 2. All evaluated treatment as Comfortable to Extremely Comfortable. The topical hyaluronidase-polysaccharide formulation has regulatory classification as a cosmetic. Based on this pilot evaluation, it may be of value in countries that prohibit injectable hyaluronidase, and for patients who decline injections. Larger, controlled studies will raise the evidence level for safety, efficacy and tolerability. It may be appropriate to evaluate nonaesthetic applications including granulomatous foreign body reactions and adjunctive acceleration of subcutaneous drug absorption and dispersion.

Lipoabdominoplasty: Comparing Ultrasound-Assisted and Power-Assisted Techniques

Introduction: Optimizing the abdomen aesthetic appearance may combine liposculpture, abdominoplasty, and postsurgical noninvasive body sculpting. The abdominoplasty traditional technique highlights abdominal flap undermining. The Avelar or Saldana lipoabdominoplasty’s technique modifications use liposuction and the absence of undermining of the abdominal wall flap. This method maintains abdominal wall vascularization and lessens complications. Two commonly employed liposuction techniques are power-assisted and ultrasound-assisted liposuction. Combining power-assisted technology with the Separation, Aspiration, Fat Equalization (SAFE) liposuction process has improved aesthetic results and reduced complications. Separation, Aspiration, Fat Equalization liposuction process enrolls separation, aspiration, and fat equalization steps. Ultrasound-assisted liposuction advantages include high-definition body sculpting through maximum fat removal and skin tightening with less blood loss and viable fat for grafting. This clinical study evaluated a comprehensive surgical protocol for lipoabdominoplasty designed to minimize complications. In addition, the study assessed aesthetic outcome and complication differences comparing the use of ultrasound-assisted versus power-assisted liposuction. Materials and Methods: This is a retrospective study in a single surgeon’s private cosmetic practice in 2 practice locations in patients undergoing a modified lipoabdominoplasty technique over a 2-year period. Results: Modified lipoabdominoplasty combining power-assisted technology with SAFE liposuction (n = 30) compared to those using ultrasound-assisted liposuction (n = 20) revealed similar complication rates. Surgeon observation revealed better skin contour smoothness, more abdominal definition and skin tightening with less bruising when using ultrasound liposuction. The comprehensive surgical protocol designed to minimize perioperative complications was implemented on each patient and resulted in no medical errors and a low major and minor complication rate. Conclusions: The lipoabdominoplasty surgical protocol provides surgeon’s comprehensive preoperative, intraoperative, and postoperative guidelines to minimize complications. Higher body mass index increased the complication rate. The aesthetic outcome using ultrasound-assisted liposuction appeared to yield better aesthetic sculpted appearance with less bruising compared to power-assisted technology.

Initial clinical experience of surface guided stereotactic radiation therapy with open-face mask immobilization for improving setup accuracy: a retrospective study

PurposeTo propose a specific surface guided stereotactic radiotherapy (SRT) treatment procedure with open-face mask immobilization and evaluate the initial clinical experience in improving setup accuracy.Methods and materialsThe treatment records of 48 SRT patients with head lesions were retrospectively analyzed. For each patient, head immobilization was achieved with a double-shell open-face mask. The anterior shell was left open to expose the forehead, nose, eyes and cheekbones. The exposed facial area was used as region-of-interest for surface tracking by AlignRT (VisionRT Inc, UK). The posterior shell provided a sturdy and personalized headrest. Patient initial setup was guided by 6DoF real-time deltas (RTD) using the reference surface obtained from the skin contour delineated on the planning CT images. The endpoint of initial setup was 1 mm in translational RTD and 1 degree in rotational RTD. CBCT guidance was performed to derive the initial setup errors, and couch shifts for setup correction were applied prior to treatment delivery. CBCT couch shifts, AlignRT RTD values, repositioning rate and setup time were analyzed.ResultsThe absolute values of median (maximal) CBCT couch shifts were 0.4 (1.3) mm in VRT, 0.1 (2.5) mm in LNG, 0.2 (1.6) mm in LAT, 0.1(1.2) degree in YAW, 0.2 (1.4) degree in PITCH and 0.1(1.3) degree in ROLL. The couch shifts and AlignRT RTD values exhibited highly agreement except in VRT and PITCH (p value < 0.01), of which the differences were as small as negligible. We did not find any case of patient repositioning that was due to out-of-tolerance setup errors, i.e., 3 mm and 2 degree. The surface guided setup time ranged from 52 to 174 s, and the mean and median time was 97.72 s and 94 s respectively.ConclusionsThe proposed surface guided SRT procedure with open-face mask immobilization is a step forward in improving patient comfort and positioning accuracy in the same process. Minimized initial setup errors and repositioning rate had been achieved with reasonably efficiency for routine clinical practice.

A Comprehensive Approach To Alloplastic Cranioplasty: Novel Implant Design And Refinement of Soft Tissue Management

Background: Large scale craniectomy defects are commonly reconstructed with alloplastic implants, which can restore brain protection and promote cosmesis. However, esthetic outcomes can be subpar due to skin contour abnormalities and temporal hollowing. Herein we describe a senior craniofacial surgeon’s experience using a custom composite polyetheretherketone (PEEK) and porous polyethylene (Medpor) implant for alloplastic cranioplasty. Methods: A retrospective review was conducted of all PEEK-Medpor cranioplasty cases performed over the past 2 years. Patient characteristics, intraoperative information, surgical outcomes, and cosmetic outcomes were reviewed. Results: Sixteen patients (18-70 years of age) underwent surgery. Indications for cranioplasty included craniectomy due to trauma, stroke, or tumor, and bone resorption after a prior autologous cranioplasty. Augmentation of the temporalis area using alloderm or a muscle graft was performed in 7 cases. There were no intraoperative complications. Ultimately, all implants were maintained. One implant was temporarily removed due to infection, but successfully replaced. Three minor complications occurred. At an average follow-up of 9 months, 93.8% of surgical sites showed no significant temporal hollow. Conclusion: We describe a series of 16 implants using a composite PEEK Medpor implant for alloplastic cranioplasty, which resulted in a low infection rate and improved postoperative regional contour. Use of this implant with suspension of the temporalis muscle is a new technique that may allow for better adherence of the temporalis muscle to its anatomic position, while still providing good brain protection.

Geometrical imaging accuracy, image quality and plan quality for prostate cancer treatments on a 1.5 T MRLinac in patients with a unilateral hip implant

Purpose. To assess the feasibility of prostate cancer radiotherapy for patients with a hip implant on an 1.5 T MRI-Linac (MRL) in terms of geometrical image accuracy, image quality, and plan quality. Methods. Pretreatment MRI images on a 1.5 T MRL and 3 T MRI consisting of a T2-weighted 3D delineation scan and main magnetic field homogeneity (B 0) scan were performed in six patients with a unilateral hip implant. System specific geometrical errors due to gradient nonlinearity were determined for the MRL. Within the prostate and skin contour, B 0 inhomogeneity, gradient nonlinearity error and the total geometrical error (vector summation of the prior two) was determined. Image quality was determined by visually scoring the extent of implant-born image artifacts. A treatment planning study was performed on five patients to quantify the impact of the implant on plan quality, in which conventional MRL IMRT plans were created, as well as plans which avoid radiation through the left or right femur. Results. The total maximum geometrical error in the prostate was <1 mm and the skin contour <1.7 mm; in all cases the machine-specific gradient error was most dominant. The B 0 error for the MRlinac MRI could partly be predicted based on the pre-treatment 3 T scan. Image quality for all patients was sufficient at 1.5 T MRL. Plan comparison showed that, even with avoidance of the hips, in all cases sufficient target coverage could be obtained with similar D1cc and D5cc to rectum and bladder, while V28Gy was slightly poorer in only the rectum for femur avoidance. Conclusion. We showed that geometrical accuracy, image quality and plan quality for six prostate patients with a hip implant or hip fixation treated on a 1.5 T MRL did not show relevant deterioration for the used image settings, which allowed safe treatment.