Search Results (170)

Background/Objectives: The implementation of tattoo-free radiotherapy (RT) for breast cancer reflects an effort to mitigate the psychological distress of permanent marks through surface-guided techniques, while simultaneously evaluating its utility in meeting setup precision requirements. Methods: In this prospective trial, patients were positioned for breast cancer RT including regional nodal irradiation exclusively using surface-guided RT (SGRT). Cone-beam computed tomography (CBCT) was acquired at each fraction as the ground truth to analyze translational setup deviations. Results: A total of 457 paired SGRT–CBCT data points in 30 patients were acquired. A residual translational setup deviation of ≤6 mm was achieved in 97.6% of all fractions with a median deviation of 2 mm (range: 0–12). Neither age, comorbidities, body mass index, extent of target volumes, choice of breathing technique, nor patient-reported symptoms (pain, dermatitis, anxiety) correlated significantly with setup deviations. The median in-room positioning time was 92 s (range: 20 s–6 min and 37 s) and significantly prolonged in patients with an elevated BMI and higher grades of pain and skin dermatitis, and for chest wall irradiation. Manual assessment of the accuracy of regional nodal CTVs in each CBCT relative to the planning CT showed good-to-minor deviations in 99.7% (Level 1/2), 95.0% (Supra-/infraclavicular), and 90.8% (Internal mammary), respectively, with major deviations in only 0.3% (Level 1/2), 5.0% (Supra-/infraclavicular) and 9.2% (Internal mammary). A forward dose calculation on CBCT geometries (n = 86) revealed high median CTV dose coverage of 100.0% (range: 57.1–107.7%) of the original target dose for all lymph node levels combined. Conclusions: The tattoo-free positioning setup for regional nodal irradiation in breast cancer patients exhibited pronounced robustness, maintaining its accuracy and reliability irrespective of patient-, tumor-, or treatment-specific variables with high clinical efficiency. However, larger cohorts are required to confirm whether these parameters genuinely operate independently of setup accuracy. Full article

Background: Tattooed teachers are increasingly visible in schools, yet the norms governing their professional acceptability remain poorly understood. This study tests whether pluralistic ignorance—private acceptance systematically exceeding the acceptance attributed to others—operates in attitudes toward tattooed teachers, and identifies individual-level predictors of this misperception. Methods: A cross-sectional online survey was conducted with 1226 individuals in Hungary across four groups: physical education (PE) teacher trainees, university students from other disciplines, secondary school students, and in-service teachers. Participants rated their own acceptance of tattooed PE and academic-subject teachers and the acceptance they attributed to other teachers and to parents, and reported tattoo status, gender, and professional background. Results: Own acceptance exceeded attributed acceptance in all four groups and for both reference targets, consistent with pluralistic ignorance; gaps were largest among secondary school students and smallest—though still positive—among in-service teachers. Personal tattoo experience was the strongest individual predictor of acceptance after group membership, and among teachers both age and experience were negatively associated with acceptance. Acceptance was predominantly conditional, structured by a visibility hierarchy in which arm placements were most acceptable and facial or neck placements least so. Conclusions: The apparent disapproval of tattooed teachers reflects collective misperception more than genuine consensus, suggesting that making actual peer attitudes visible could reduce conformity pressure and support more authentic professional self-expression. Full article

In-vivo diabetes detection of glucose was sought using square-wave anodic stripping voltammetry (SW), with bismuth-immobilized carbon nanotube paste electrode (BCE), and skin tattoo painted wearable circuits. The optimum analytical results indicated sensitivity of 0.0781 μg/L peak signals on the BCE. The raw voltammogram was approached within the in vivo detection ranges of 10–90 μg/L, with preconcentration times of 50 s attained. The relative standard deviation was micro ranges under optimum conditions. The analytical detection limit (S/N) was attained at a nano range of 5.5 nM. The handmade microsensor was directly used in vivo on the living fish brain and human urine. The method was applied at real time in vivo, without requiring any pretreatment and other ionic electrolyte solutions. It can be used for medicinal and other materials requiring biological-fluid detection in real time. This study was designed to be suitable for real-time unmanned remote diagnosis and therapeutic drug injection into the body, micro-needle long-term administration, wearable artificial skin tattoo sensor, and real-time control. In addition, the glasses monitor was designed to be suitable for multitasking and multi-user control sensing. Full article

Wearable electroencephalography (EEG) is rapidly evolving toward lightweight, user-friendly systems that enable brain monitoring in naturalistic settings. Traditional multi-channel, gel-based systems provide broad scalp coverage and high signal fidelity but are impractical for unsupervised or long-term use. This review focuses on the emerging generation of smart wearable EEG devices that are easy to wear, require minimal setup, and typically integrate additional physiological sensors such as photoplethysmography (PPG), temperature, or motion sensors. We review wearable EEG systems across four main form factors: head-worn EEG devices, smart EEG patches and tattoos, in-ear and headphone-based EEG, and glasses-integrated EEG. Head-worn systems offer broader signal coverage and support more complex applications such as sleep staging, human–machine interaction, and epilepsy monitoring. Patch-based systems are well suited to comfortable long-term monitoring, particularly in sleep-related applications. Ear-center systems provide high user comfort and stable signal acquisition from non-traditional electrode locations. Glasses-integrated devices represent an emerging option for unobtrusive daytime neurophysiology. Each category is examined in terms of sensor fusion, technical parameters, and embedded algorithms, with particular emphasis on automated signal analysis. We conclude with a discussion on current limitations, regulatory and usability challenges, and future directions toward unobtrusive, AI-powered neurotechnology for home and clinical use. Full article

Background: Precise intraoperative localisation of small colorectal tumours during laparoscopic surgery remains challenging due to absent tactile feedback and subserosal tumour location. Current standard methods, particularly India ink tattooing, demonstrate 15–30% failure rates for lesions less than 10 mm, leading to prolonged operative times, incomplete resections, and re-operations. Multiple emerging technologies promise improved localisation, yet comparative evidence remains fragmented. Objective: To map and characterise the current landscape of intraoperative marking and identification technologies for small colorectal tumour localisation during laparoscopic surgery, with emphasis on radiofrequency-based methods and alternative approaches, and to identify evidence gaps guiding future research. Methods: Following PRISMA-ScR guidelines, we systematically searched PubMed, Web of Science, and Scopus databases from January 2000 through December 2025 for studies evaluating tumour localisation technologies in colorectal cancer surgery, including primary tumour localisation during laparoscopic colectomy and localisation of colorectal liver metastases during hepatic surgery, or transferable anatomical applications with documented translational potential to colorectal surgery. Two independent reviewers screened all records, with discrepancies resolved through discussion and a third senior reviewer consulted for unresolved disagreements; data were extracted on technical performance, safety, feasibility, cost-effectiveness, usability, innovation potential, and evidence quality. Results: We included 89 studies comprising 18 colorectal-specific articles and 71 transferable/GI-adjacent studies. Detection success rates ranged from 71% to 100% across modalities. Near-infrared fluorescence with indocyanine green demonstrated the strongest clinical evidence with 75–100% detection across eight colorectal studies encompassing 2134 procedures and seamless workflow integration. Radiofrequency identification systems achieved 91.9–99% detection in feasibility studies with promising tissue penetration of 15–35 mm but limited colorectal validation. Electromagnetic navigation excelled in rigid organs with 85–98% success but showed degraded performance in mobile bowel at 71–75%. Critical evidence gaps included absent head-to-head comparative trials, non-standardised outcome metrics limiting cross-study comparability, and limited long-term safety data with only 14 studies providing follow-up exceeding six months. Conclusions: ICG fluorescence represents the most clinically mature technology identified, representing a priority candidate for colorectal-specific validation in challenging localisation scenarios. RFID systems demonstrate promising characteristics justifying prioritised research investment through adequately powered comparative trials. Future research must emphasise consortium-based comparative effectiveness studies, standardised outcome metrics, and integration with robotic and AI-assisted surgical platforms to accelerate clinical translation. Full article

Background/Objectives: This study investigates the hypothesis that transient oxygen depletion is the mechanism of the skin sparing effect of ultra-high dose-rate irradiation, commonly referred to as FLASH irradiation. Methods: Two skin tattoo dots were placed approximately 1.0 cm apart on the thigh of FVB/N mice. The area overlapping the dots was irradiated with a single dose of 27 Gy protons delivered with either FLASH (~120 Gy/s) or 0.5 Gy/s conventional dose-rate (CDR) irradiation. Skin contraction was assessed by measuring the distance between the tattoo dots and complemented by histopathological skin analyses. Mice were placed in a 1.4 L chamber flushed with 5%, 7%, 20.9% or 100% oxygen (balance nitrogen, where applicable) prior to and during irradiation. Skin oxygenation was measured non-invasively using the phosphorescence quenching method. Results: Compared to air-breathing mice, skin contraction increases in mice breathing 100% oxygen and decreases when breathing 7% and 5% oxygen following CDR irradiation, showing that skin is neither fully oxygenated nor hypoxic. FLASH irradiation reduced skin contraction, epidermal thickening, and fibrosis in air-breathing mice compared to CDR irradiation. The difference between FLASH and CDR skin contraction decreases as the inspired gas oxygen content is reduced from 20.9% to 7%. Under 5% oxygen breathing conditions, the FLASH sparing effect is eliminated. Conclusions: Mean normal tissue pO₂ does not reveal the presence of cells at low pO₂ that could become susceptible to FLASH-induced radiobiological hypoxia at doses lower than would be predicted from the mean tissue pO₂ value. In the absence of oxygen, FLASH skin sparing for the late normal tissue effect, skin contraction, is eliminated. Full article

Pigment implantation (semi-permanent make-up, microblading and cosmetic tattooing) introduces complex pigment mixtures into the dermis, resulting in direct exposure of keratinocytes, fibroblasts and resident immune cells to metals, organic dyes and nanoparticles. Within Somatology and Somatic therapy practice, an allied health discipline concerned with evidence-based care of the skin and body, Somatic Therapists operate at the interface of dermal intervention, molecular exposure and occupational health, underscoring the relevance of mechanistic toxicology for risk-informed professional practice. This PRISMA-guided systematic review synthesises molecular toxicology and omics-based evidence, emphasising oxidative stress generation, inflammatory signalling via NF-κB/MAPK pathways, apoptosis and genotoxicity, T-cell-mediated type IV hypersensitivity reactions associated with modern red azo pigments, and dermal-to-lymphatic transport of particulate matter. Transcriptomic and metabolomic studies consistently demonstrate pigment-specific inflammatory responses and wound-healing gene signatures, supporting mechanism-driven biocompatibility profiling. Regulatory frameworks, including EU REACH Annex XVII Entry 75 and recent FDA guidance on microbial contamination, have strengthened compliance requirements; however, surveillance continues to identify mislabelling, restricted pigments and microbial contamination in some inks. For Somatology and Somatic therapy practice, these findings highlight the importance of evidence-based pigment selection, traceable sourcing, aseptic technique, ventilation, personal protective equipment and informed consent addressing pigment migration and delayed adverse reactions. The integration of molecular outcomes with omics technologies and regulatory oversight provides a next-generation risk assessment framework to advance safe cosmetic practice and public health. Full article

This study investigates the composition, morphology and cultural significance of red pigment traces identified on bone pointed tools discovered in the Chalcolithic tell settlement of Pietrele–Măgura Gorgana, attributed to the Kodjadermen–Gumelnița–Karanovo VI cultural complex (4600–4250 BC). The observed use-wear patterns are consistent with repeated contact with soft, non-abrasive materials, including hide working, pigment application on leather or other organic surfaces, fiber manipulation, and perforation of soft substrates. Use-wear analysis revealed polished and flattened distal ends, compatible with repeated use on soft, non-abrasive materials, such as hide, leather, fiber, or other organic substrates. The possibility of pigment application directly on skin, in a practice analogous to tattooing, as previously published, cannot be excluded but remains speculative in the absence of experimental reference data or residue evidence specifically linked to such use. An associated ceramic container was tentatively interpreted as a possible vessel for ochre preparation, suggesting local processing of the pigment. The artifacts were investigated using multi-analytical archaeometric methods: SEM-EDS, AFM, TEM, FTIR, Raman, TGA, CLSM and pseudo-color image segmentation and 3D rendering of porosity distribution. The results consistently identified an iron oxide-based pigment, dominated by hematite and/or goethite, specific to ochre. Pigment particles (50–300 nm) form a well-defined superficial layer on the bone substrate, without Fe–Ca reactions at the interface. The simultaneous presence of Ca, P, Si, Mg and K indicates a silicate matrix with an apatite component, compatible with local and poorly purified raw materials. CIELAB colorimetric analyses revealed significant chromatic variability, suggesting the use of hematite-rich pigments and possible thermal transformations of goethite. The results contribute to the understanding of the pigment technologies of the Chalcolithic communities of the Lower Danube. Full article

The determination of soluble elemental contaminants in tattoo inks is challenged by the lack of standardized extraction procedures, limiting the comparability of analytical results and the assessment of exposure-relevant fractions under the European REACH framework. In this study, artificial sweat extraction was applied as a mild and physiologically relevant approach to evaluate elements potentially released from tattoo inks under sweat-simulated skin-contact conditions. Seventy-eight commercial tattoo inks of different colors were extracted with artificial sweat at 37 °C for 1 h and analyzed by inductively coupled plasma mass spectrometry. Optimization of collision/reaction cell conditions, dilution strategy, and internal standard correction effectively reduced matrix-related interferences caused by the high salt and chloride content of artificial sweat, ensuring reliable quantification. Matrix-matched calibration was required due to significant signal suppression for several analytes. Method accuracy and precision, assessed using NIST 1643f and spiked samples, were generally satisfactory. Elemental release showed marked color-dependent trends, particularly for Cu, Zn, Ba, Al, Ga, Si, Sr, and Zr, reflecting differences in pigment composition and formulation. Soluble Ba, Cu, and Zn remained below EU regulatory limits. While total digestion remains essential for complete characterization, the proposed methodology provides a simple and transferable tool for exposure-oriented assessment of potentially bioaccessible elements in tattoo inks. Full article

Aromatic amines (AAs) are potent carcinogens found in tattoo inks that pose significant health risks. Precise quantitative analysis is essential for safety. In this study, we developed and validated a robust method for the simultaneous quantification of 21 regulated AAs using both gas chromatography–electron ionization (GC-EI)–mass spectrometry (MS) and tandem MS (MS/MS). After optimizing separation conditions, MS-based selected ion monitoring (SIM) and MS/MS-based multiple reaction monitoring (MRM) were evaluated. While both methods were largely sufficient to ensure compliance with international safety thresholds, the MRM-based approach exhibited superior detection capability with comparable analytical accuracy and precision, providing a more effective tool for trace-level hazardous compound analysis. The developed MRM method was applied to eight commercial tattoo inks, identifying five AAs in five products. Notably, o-toluidine, o-anisidine, and 3,3′-dichlorobenzidine significantly exceeded the regulatory limit (5.0 mg/kg), particularly in green and yellow inks. The dual-capability GC-MS platform—combining high-performance MRM quantification with robust spectral confirmation—ensures the high throughput and analytical confidence necessary for regulatory compliance and public health protection. Full article

Background/Objectives: Accurate intraoperative tumour localisation remains challenging in minimally invasive colorectal surgery, where conventional tattooing methods suffer from marker migration, tissue diffusion, and potential allergic reactions. Radio frequency identification (RFID) technology offers a promising alternative through implantable passive transponders detectable via electromagnetic coupling, eliminating ionising radiation exposure. Methods: This preclinical feasibility study evaluated three RFID frequency bands for surgical tumour marking: 134 kHz (low frequency, LF), 13.56 MHz (high frequency, HF), and 868 MHz (ultra-high frequency, UHF). Finite element electromagnetic simulations characterised antenna field distributions, while experimental validation employed glass-encapsulated transponders in air and tissue-simulating saline (0.9% NaCl, σ ≈ 1.5 S/m). Detection ranges were measured across 28 angular configurations with expanded measurement uncertainty (k = 2) ranging from ±0.9 to ±3.2 mm. Results: Maximum detection distances in air were 25.0 ± 0.9 mm (LF), 23.0 ± 1.1 mm (HF), and 68.0 ± 2.3 mm (UHF). In saline, ranges decreased to 22.5 ± 1.0 mm, 20.7 ± 1.2 mm, and 18.0 ± 1.4 mm, respectively, demonstrating tissue attenuation of 10% at LF/HF vs. 74% at UHF. Angular characterisation revealed 64–70% range reduction at orthogonal orientation for LF/HF systems. Computational–experimental correlation yielded r² = 0.975 across 154 paired observations. Conclusions: The 13.56 MHz HF band emerges as the optimal candidate for clinical translation, offering adequate tissue penetration (20.7 mm), superior antenna miniaturisation potential (5 mm diameter), established biocompatibility pathways, and mature near-field communication ecosystem support. Future development should address angular sensitivity through multi-axis antenna configurations and validation in anatomically realistic tissue phantoms. This study establishes the electromagnetic evidence base for clinical system development; translation to clinical practice requires sequential preclinical and clinical evaluation. Full article

Conventional gel electrodes are the gold standard for surface electromyography (sEMG), yet their bulkiness, stiffness, and limited gel lifetime prevents seamless day-long integration with wearable robots. We integrated ultrathin skin-conformal temporary tattoo electrodes with a powered unilateral hip exoskeleton and compared signal quality during treadmill walking against gel. In this pilot study, five healthy participants completed three consecutive walking blocks at fixed speed: (1) using gel electrodes; (2) using tattoo electrodes to compare signal quality; and (3) using the same tattoo electrodes (not repositioned) after eight hours of wear to simulate a full day of typical device use and to evaluate potential degradation in signal quality over time. Electrodes were positioned on muscles not covered by the exoskeleton interface (tibialis anterior and gastrocnemius medialis), as well as on muscles located beneath the exoskeleton cuff, which were potentially subject to motion artifacts due to the application of external forces by the exoskeleton (rectus femoris and biceps femoris, BF). Across all muscles, for both gel and tattoo electrodes, the root mean square error (RMSE) between normalized sEMG envelopes and biological activation profile was 0.069 ± 0.048, and Pearson’s correlation coefficient (ρ) was 0.844 ± 0.091. Re-testing the same tattoo electrode pair after eight hours confirmed day-long stability without the need for recalibration. Statistical analysis revealed no significant differences in signal quality, also when applying assistive forces, between the two electrode types and across all muscles (RMSE, all p ≥ 0.3125; ρ, all p ≥ 0.1250), as well as no degradation after eight hours (RMSE and ρ: all p ≥ 0.0626, uncorrected). Finally, in a proof-of-concept session, BF activity measured with tattoo electrodes was found reliable to drive hip-extension assistance in real time. Collectively, these results show that tattoo electrodes deliver signal quality comparable to gel electrodes while offering a low-profile skin-conformal interface and day-long usability, making them a promising option for enhancing EMG-based control in wearable robots. Full article

Objectives: The study aimed to comprehensively assess the impact of tattoos on the structural and functional properties of the skin in healthy women. Methods: The investigation included 22 female participants aged 19–41 years, covering a total of 88 tattoos. Various diagnostic tools were employed: a Tewameter TM300 to evaluate transepidermal water loss (TEWL), a Corneometer and Cutometer to measure skin hydration, elasticity, and firmness, and high-frequency ultrasonography (HFUS) to assess epidermal thickness and skin echogenicity. The results showed that the presence of tattoos did not significantly influence TEWL values. Although regional differences in TEWL were observed in non-tattooed skin, tattooed skin showed no such variability, suggesting a consistent barrier function regardless of tattoo location. Corneometric and cutometric assessments revealed no significant differences in hydration, elasticity, or firmness between tattooed and non-tattooed skin. These parameters were also not influenced by tattoo age, although a physiological decline in mechanical skin properties was observed with increasing participant age. HFUS indicated a significantly thinner epidermis in tattooed areas compared to their non-tattooed counterparts. Additionally, tattooed skin demonstrated a higher percentage of low-echogenicity pixels in the lower dermis, suggesting localized structural changes. However, neither the age of the tattoo nor the age of the participant significantly affected the ultrasound parameters. Conclusions: Tattoos did not impair key skin functions such as hydration, elasticity, or barrier integrity, but were associated with structural changes observable via high-frequency ultrasonography. Full article

Background: This study aims to characterize the clinical features and outcomes of tattoo-associated sarcoid-like uveitis using a multicenter uveitis registry given the limited existing data. Design: This is a retrospective study. Participants: Ten patients (20 eyes) diagnosed with tattoo-associated sarcoid-like uveitis took part in the study. Methods: The data of patients newly evaluated at participating registry centers from January 2000 to June 2025 were reviewed. Demographic data, treatments, visual acuity, recurrence, glaucoma/intraocular pressure (IOP)-lowering therapy, extraocular involvement, and histologic confirmation were extracted when available. Main Outcome Measures: Recurrence, glaucoma/IOP-lowering therapy, extraocular involvement, and change in logarithm of the minimum angle of resolution (logMAR) from presentation to final follow-up were measured. Results: Seven (70%) patients were male, and the patients’ mean age was 35.1 ± 7.8 years. All patients exhibited bilateral ocular involvement. Histologic confirmation at the tattoo site was documented in five (50%) patients. The mean logMAR visual acuity was 0.12 ± 0.31 at presentation and 0.16 ± 0.42 at the final follow-up (median follow-up: 20 months). All patients received topical corticosteroids; periocular steroids were administered in seven cases (70%), oral systemic steroids in four (40%), adalimumab in two (20%), and cyclosporin in one (10%). Seven cases (70%) developed uveitis recurrence, and eight received glaucoma/IOP-lowering therapy (80%). Extraocular inflammation affected the skin/tattoo in seven patients (70%) and the axillary lymph nodes in one (10%). This finding is definitive; however, this is also true even when the organ/body part is plural (e.g., lungs). Conclusions: Tattoo-associated sarcoid-like uveitis often follows a chronic course with frequent recurrence and uveitic glaucoma. Thus, close ophthalmic monitoring and coordinated systemic evaluation may be warranted. Full article

Flexible skin electronics are increasingly sought after for their potential in sensing and drug delivery within wearable human–machine interfaces. However, developing multifunctional applications that maintain biocompatibility and stable electrical performance under various mechanical deformations remains a challenge. Here, we introduce tattoo paper-based graphene–gold conductors that are approximately 0.04 mm thick and feature a dual conductive pathway within the graphene–gold film. By integrating a folding structure with this dual conductive pathway, we can mitigate the strain effects on the electrical resistance of film-based conductors, resulting in wider areas of stable resistance. In addition, we have designed film conductors with a kirigami structure, which achieves a high initial conductivity of 1.5 × 10³ S cm⁻¹ and exhibits negligible resistance changes across a broad strain range of 0 to 130%. We utilize these conductors to develop waterproof on-skin patches that incorporate electrically and optically active heaters for body heating and drug delivery. Furthermore, we have created an on-skin dialing interface using these conductors, which enables users to make telephone calls based on triboelectric nanogenerators. Full article