Hyperspectral Imaging Detects Clitoral Vascular Issues in Gender-Affirming Surgery.

The aim of this study was to assess the efficacy of hyperspectral imaging (HSI) as an intraoperative perfusion imaging modality during gender affirmation surgery (GAS). The hypothesis posited that HSI could quantify perfusion to the clitoral complex, thereby enabling the prediction of either uneventful wound healing or the occurrence of necrosis. In this non-randomised prospective clinical study, we enrolled 30 patients who underwent GAS in the form of vaginoplasty with the preparation of a clitoral complex from 2020 to 2024 and compared patients' characteristics as well as HSI data regarding clitoris necrosis. Individuals demonstrating uneventful wound healing pertaining to the clitoral complex were designated as Group A. Patients with complete necrosis of the neo-clitoris were assigned to Group B. Patient characteristics were collected and subsequently a comparative analysis carried out. No significant difference in patient characteristics was observed between the two groups. Necrosis occurred when both StO2 and NIR PI parameters fell below 40%. For the simultaneous occurrence of StO2 and NIR PI of 40% or less, a sensitivity of 92% and specificity of 72% was calculated. Intraoperatively, the onset of necrosis in the clitoral complex can be reliably predicted with the assistance of HSI.

Diagnostical accuracy of hyperspectral imaging after free flap surgery.

Microsurgical free-tissue transfer has been a safe option for tissue reconstruction. This study aimed to analyze the diagnostic accuracy of hyperspectral imaging (HSI) after free-tissue transfer surgery. From January 2017 to October 2019, 42 consecutive free-flap surgeries were performed, and their outcomes were analyzed via HSI. Clinical examination of free-flap perfusion was initially performed. Clinical examination findings were subsequently compared with those of HSI. Potential venous congestion with subsequent necrosis was defined as a tissue hemoglobin index of ≥53%. Student's t-test was used to compare the results of the analysis. The evaluation of sensitivity and specificity for flap failure detection was time dependent using the Fisher's exact test. A p-value of ≤0.05 was considered statistically significant. Microsurgical tissue transfer success rate was 84%. Seven patients presented with venous congestion that caused total flap necrosis. Overall, 124 assessments were made. HSI accurately identified 12 out of 19 pathological images: four as false positive and seven as false negative. The sensitivity and specificity of HSI were 57 and 94%, respectively, compared to those of clinical examination that were 28 and 100%, respectively, within 24 h following tissue transfer. The sensitivity and specificity of HSI were 63 and 96%, respectively, compared to those of clinical examination that were 63 and 100%, respectively, within the first 72 h. A tissue hemoglobin index of ≥53% could predict venous congestion after free-flap surgery. HSI demonstrated higher sensitivity than clinical examination within the first 24 h; however, it was not superior compared to clinical findings within 72 h.

Pathogens and Shift of Resistance in Early Infections after Operative Fracture Fixation.

Background: Surgical site infections (SSIs) remain a challenge for the healthcare system. During the last 30 years, the literature has shown an increase of gram-negative bacterial strains in multiple infectious sites and that cephalosporins have replaced penicillin as the gold standard in peri-operative antibiotic prophylaxis. This study aims to examine the recent bacterial spectrum in orthopedic early SSIs and to compare it with a historical cohort. Patients and Methods: Patients in a level 1 trauma center with an SSI within six weeks after open fixation of a fracture were analyzed in two adjacent periods from 2007 to 2012 (data pool 1; DP1) and 2013 to 2017 (data pool 2; DP2), retrospectively. The detected microbiologic pathogens and the associated resistograms from both time periods were compared. Results: Six hundred eighty-one smear tests and respective pathogens from the wounds of 463 patients (mean age, 62.6 ± 20 years) with SSIs were analyzed. The following pathogens were found most frequent: Staphylococcus epidermidis (DP1, 20.6%; DP2, 26.3%), Staphylococcus aureus (DP1, 27.1%; DP2, 16.5%), Enterococcus faecalis (DP1, 13.7%; DP2, 11.1%), Bacillus sp. (DP1, 3.0%; DP2, 5.3%), Escherichia coli (DP1, 5.1%; DP2, 4.1%), Pseudomonas aeruginosa (DP1, 3.7%; DP2, 2.5%). In DP2, there were lower primary early infection rates with Staphylococcus aureus than in DP1 (p = 0.002). In DP2, Staphylococcus epidermidis showed an oxacillin resistance in 90.6% and an increased resistance (79.8%; p = 0.069) to several classes of antibiotic agents compared to DP1. Conclusions: No bacterial shift toward gram-negative species was observed in this investigation. However, Staphylococcus epidermidis showed an increased antibiotic resistance in the more recent patient cohort. The incidence of SSIs with Staphylococcus aureus decreased substantially.

[Change of Gaze Pattern depending on the Stage of DIEP Flap Breast Reconstruction: a Preliminary Eye-Tracking Investigation]. / Veränderung des Blickmusters in Abhängigkeit des Stadiums der Brustrekonstruktion mittels DIEP Lappenplastik ­ erste Daten einer Eye-Tracking-Analyse.

BACKGROUND: Breast reconstruction using autologous tissue is an integral part of breast cancer treatment. While many studies have elucidated the impact of breast reconstruction on patients' quality of life, self-esteem, sexuality and more, there is a lack of objective data regarding the effects on external observers. Aim of this study was to investigate the change in gaze pattern of independent observers depending on the stage of DIEP-flap breast reconstruction. MATERIALS AND METHODS: Eye-tracking technology was utilized to analyze the eye movements of 58 study participants while viewing 2 D photographs of a patient after mastectomy and different stages of DIEP-flap breast reconstruction. Time until first fixation and total time of fixation were recorded and con- secutively analyzed for the right and left breast on each image. RESULTS: Overall, the total time of fixation of the operated breast decreased significantly over the different stages of breast reconstruction, with p<0.001. At the same time, there was no statistically significant change in total time of fixation of the non-operated breast, with p=0.174. The time until first fixation showed a significant increase over the different stages of reconstruction for the reconstructed breast, with p<0.001, while no significant differences were found for the opposite breast, with p=0.344. CONCLUSION: Mastectomy and the individual steps of breast reconstruction alter the perception of breast cancer patients. Over the course of breast reconstruction, the deviation of gaze in the direction of the affected breast is reversed.

3D Anthropometric Facial Imaging - A comparison of different 3D scanners.

Facial measurements serve as a valuable tool in the treatment planning of facial plastic surgery. The aim of this study was to evaluate the accuracy and reliability of standard 3D anthropometric measurements of the face made with one low-cost handheld 3D scanner and one industrial-type mobile 3D scanner. There are clear potential benefits of using 3D measurements by means of new handheld mobile scanners. However, the Sense scanner from the class of inexpensive scanners showed significant limitations in more complex areas such as the lip and nose, whereas proportions could be measured satisfactorily.

Anatomic Differences Between the Asian and Caucasian Nose and Their Implications for Liquid Rhinoplasties.

The demand for surgical and nonsurgical esthetic procedures in the nasal region has increased sharply in the past. Anatomic differences of the nose between different ethnicities need to be investigated thoroughly. The objective of this article is to analyze and compare morphometric features of the nose in a mixed Asian-Caucasian study population. The nasal length in Asians was statistically significantly greater than in Caucasians, also after having adjusted for facial height. The nasal dorsal bridge and the nasal base showed statistically significant differences. By keeping these anatomic differences in mind while treating patients, greater efficacy and safety can be achieved.

Effect of Surgical versus Nonsurgical Rhinoplasty on Perception of the Patient: An Eye-Tracking-Based Investigation.

Because of its central location in the face, the nose plays an important role in the aesthetic perception of the face. To improve the appearance of the nose, surgical and nonsurgical rhinoplasty techniques have been described, although it still remains elusive if both options show comparable results in their aesthetic perception. This study assesses the fixation pattern and duration when looking at postinterventional images compared with baseline images for surgical and nonsurgical rhinoplasty procedures. According to this study, the nasal appearance, especially in a lateral view, is more fundamentally altered when surgical rhinoplasty is performed, compared with nonsurgical rhinoplasty.

Facial Recognition Pattern before and after Lower Eyelid Blepharoplasty: An Eye Tracking Analysis.

This study investigated eye movement patterns using eye tracking technology when looking at preoperative and postoperative images of patients that underwent bilateral periorbital cosmetic surgery. The sequence of facial recognition before surgery was periorbital-nose-perioral, whereas following surgery it was nose-periorbital-perioral. This study revealed that the sequence of facial feature recognition is influenced by the aesthetic liking of the observer and that alteration to facial features influences the sequence of facial feature recognition. The eye movement pattern, however, seems to follow the internal representation of beauty where aesthetically pleasing facial features are observed later during first image exposure and are viewed shorter.

Reliability of 3-dimensional surface imaging of the face using a whole-body surface scanner.

OBJECTIVE: To the knowledge of the authors, no data about the reproducibility and accuracy of 3-dimensional surface imaging of the face using a whole-body scanner are available. Thus, the objective of this investigation was to assess the reproducibility of facial scans acquired using a whole-body imaging device. MATERIAL AND METHODS: This investigation investigated 220 3-D scans of a total of 22 healthy volunteers (with a mean age of 29.36 years). Two consecutive 3-D images using a Vectra WB360 of the volunteers were obtained utilizing a whole-body imaging device. Predefined distances in the face were performed in each scan and compared. Furthermore, surface deviation between two consecutively captured scans was assessed. RESULTS: The distance with the smallest statistical significance was found to be at the nose with p = 0.998, while the biggest statistical significance was found in the midface with p = 0.658. The area with the biggest surface deviation between the superimposed scans was the neck with a root mean square (RMS) of 1.62 ± 1.71, and the area with the smallest surface deviation was the forehead with a RMS of 0.17 ± 0.05. CONCLUSION: The whole-body imaging device investigated in this study can be utilized to capture the face and provides enough accuracy to compare scans. Even though not directly investigated, it can be hypothesized that the error caused by repositioning the patient between a baseline and a follow-up scan will not be too big to consider measurements performed with the whole-body imaging device as impractical.

Identifying the most attractive umbilical position - an eye tracking- and survey-based investigation.

Abdominoplasty is a popular procedure in plastic surgery providing aesthetic, functional and psychological relief for patients suffering from excess abdominal tissue. Correct umbilical positioning is crucial for a successful aesthetic surgical outcome. This study aims to assess the most attractive position of the umbilicus by means of subjective and objective outcome measures. 58 Caucasian study participants with a mean age of 36.87 (15.6) years rated eight different umbilical positions. The various positions were determined based on the ratio of the distance between the xiphoid process and the umbilicus and the distance between the umbilicus and the infra-umbilical crease: 1:1, 1.25:1, 1.5:1, 1.75:1, 2:1, 2.5:1, 3:1 and 5.5:1. Semi-quantitative scoring of attractiveness based on a 5-point Likert scale and eye tracking analyses were utilized. The results revealed that the volunteers perceived as most attractive the ratio of 2:1 with 4.32 (out of possible 5.0). The ratio of 5.5:1 received the lowest rating with 1.8. The results of the objective eye tracking analyses confirmed the subjective rating as the 2:1 ratio was fixated last amongst all other displayed ratios with 1.85 s whereas the 5.5:1 ratio had the shortest interval between image display and first stable eye fixation with 0.94 s. The study confirms the concept of 'internal representation of beauty'. Abdominoplasty procedures could rely on this easy to perform ratio by dividing the distance into thirds and using the boundary between the inferior and middle third as a clinically reliable landmark.

The Impact of Breast Symmetry on Eye Movement and Gaze Pattern: An Eye-Tracking Investigation.

BACKGROUND: The objective assessment of beauty remains challenging despite ongoing research efforts. A new method of objectively determining the aesthetic appeal of body features by analyzing gaze patterns and eye movements has recently been investigated. OBJECTIVES: The objective of this study was to assess, by means of objective eye-tracking technology, differences in the gaze patterns of observers presented with standardized 3-dimensional images showing different degrees of breast asymmetry. METHODS: A total of 83 Caucasian study participants with a mean age of 38.60 (19.8) years were presented with 5 images depicting varying degrees of breast asymmetry. In addition to the assessment of eye movements, participants were asked to rate the aesthetic appeal and the asymmetry of the breasts on a 5-point Likert scale. RESULTS: Overall, the data showed that participants' rating of the breasts' aesthetic appeal was inversely related to the level of asymmetry. The mean [standard deviation] time until fixation was shortest for the image depicting the greatest breast asymmetry (50 cc) at 0.77 [0.7] seconds (P < 0.001). In addition, the mammary region was also viewed longest in this image at 3.76 [0.5] seconds (P < 0.001). A volume difference of 35 cc between breasts deflected the observers' gaze significantly toward the larger of the asymmetric breasts (P < 0.001). CONCLUSIONS: Surgeons should focus on achieving symmetric breast volume (ie, differences <35 cc between breasts) to avoid noticeable asymmetry with regard to breast size.

Hyperspectral Imaging (HSI) as a new diagnostic tool in free flap monitoring for soft tissue reconstruction: a proof of concept study.

OBJECTIVES: Free flap surgery is an essential procedure in soft tissue reconstruction. Complications due to vascular compromise often require revision surgery or flap removal. We present hyperspectral imaging (HSI) as a new tool in flap monitoring to improve sensitivity compared to established monitoring tools. METHODS: We performed a prospective observational cohort study including 22 patients. Flap perfusion was assessed by standard clinical parameters, Doppler ultrasound, and HSI on t0 (0 h), t1 (16-28 h postoperatively), and t2 (39-77 h postoperatively). HSI records light spectra from 500 to 1000 nm and provides information on tissue morphology, composition, and physiology. These parameters contain tissue oxygenation (StO2), near-infrared perfusion- (NIR PI), tissue hemoglobin- (THI), and tissue water index (TWI). RESULTS: Total flap loss was seen in n = 4 and partial loss in n = 2 cases. Every patient with StO2 or NIR PI below 40 at t1 had to be revised. No single patient with StO2 or NIR PI above 40 at t1 had to be revised. Significant differences between feasable (StO2 = 49; NIR PI = 45; THI = 16; TWI = 56) and flaps with revision surgery [StO2 = 28 (p < 0.001); NIR PI = 26 (p = 0.002); THI = 56 (p = 0.002); TWI = 47 (p = 0.045)] were present in all HSI parameters at t1 and even more significant at t2 (p < 0.0001). CONCLUSION: HSI provides valuable data in free flap monitoring. The technique seems to be superior to the gold standard of flap monitoring. StO2 and NIR PI deliver the most valuable data and 40 could be used as a future threshold in surgical decision making. Clinical Trial Register This study is registered at the German Clinical Trials Register (DRKS) under the registration number DRKS00020926.

Scar quality examination comparing titanium-coated suture material and non-coated suture material on flap donor sites in reconstructive surgery.

BACKGROUND: Wound healing and scar quality after trauma are subject to impairment through excessive wound healing, chronic wound or even surgical site infections. Optimizing the process of scar formation and skin healing is crucial in virtually all fields of medicine. In this regard, we tested the possible usage and advantages of titanium coated suture material. METHODS: We performed a prospective observational cohort study including 30 patients who underwent soft tissue reconstruction. One half of the donor flap site was sutured with titanium coated suture material, while the other half was closed with non-coated sutures. Scar quality of the donor flap site was assessed by photographs and POSAS scores on days 2-5, 14, 42, 72 and 180 postoperatively. RESULTS: No difference between the titanium coated sutures and non-coated sutures was seen in the POSAS assessment, neither for the patient scale at 14, 42, 72 and 180 days, nor for the observer scale on the same dates. Comorbidities like diabetes, chronic renal failure and smoking as well as the BMI of each patient affected the wound healing process to an equal degree on both sides of the suture. CONCLUSIONS: No difference between the titanium coated and non-titanium-coated suture material was seen in the POSAS assessment in regard to scar quality and wound healing. The titanium-coated suture material can be considered to be equally as effective and safe in all qualities as the non-titanium-coated suture material, even in patients with comorbidities. Clinical trial register This study is registered at the German Clinical Trials Register (DRKS) under the registration number DRKS00021767. ( https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00021767 ).

A Baseline Wander Tracking System for Artifact Rejection in Long-Term Electrocardiography.

Long-term electrocardiogram (ECG) signals might suffer from relevant baseline disturbances during physical activity. Motion artifacts in particular are more pronounced with dry surface or esophageal electrodes which are dedicated to prolonged ECG recording. In this paper we present a method called baseline wander tracking (BWT) that tracks and rejects strong baseline disturbances and avoids concurrent saturation of the analog front-end. The proposed algorithm shifts the baseline level of the ECG signal to the middle of the dynamic input range. Due to the fast offset shifts, that produce much steeper signal portions than the normal ECG waves, the true ECG signal can be reconstructed offline and filtered using computationally intensive algorithms. Based on Monte Carlo simulations we observed reconstruction errors mainly caused by the non-linearity inaccuracies of the DAC. However, the signal to error ratio of the BWT is higher compared to an analog front-end featuring a dynamic input ranges above 15 mV if a synthetic ECG signal was used. The BWT is additionally able to suppress (electrode) offset potentials without introducing long transients. Due to its structural simplicity, memory efficiency and the DC coupling capability, the BWT is dedicated to high integration required in long-term and low-power ECG recording systems.

Diagnostic and prognostic impact of desmocollins in human lung cancer.

OBJECTIVE: Desmosomes are intercellular junctions that confer strong cell-cell adhesion. Two main members of desmosomal cadherins, desmogleins (DSGs) and desmocollins (DSCs), are involved in carcinogenesis. However, their role in human lung cancer remained elusive. The aims of this study were to analyse the expression of DSCs and to evaluate their clinical application in lung cancer. METHODS: The expression of DSC1-3 mRNAs was analysed by RT-PCR. The methylation status of DSCs was analysed by demethylation tests and bisulphite sequencing. Protein expression of DSCs in primary lung cancer was evaluated by immunohistochemistry on tissue microarrays. RESULTS: DSC1-3 mRNAs were downregulated in lung cancer cells, and the expression was restored in four out of seven cell lines, respectively, after 5-aza-2'-deoxycytidine treatment. A heterogeneous methylation pattern was detected by bisulphite sequencing in exon 1 of DSC2 and DSC3. In 199 patients with primary lung cancer, we found that lower protein expression of DSC1 was significantly linked to worse tumour differentiation (p=0.017), DSC3 proteins were more expressed in squamous cell carcinoma (SCC) compared with adenocarcinoma (ADC) (p<0.001), and reduced expression of DSC1 and DSC3 was significantly correlated with poor clinical outcome (p=0.045 and p=0.007, respectively). CONCLUSIONS: Our data suggest that downregulation of DSC1-3 may be explained by DNA methylation, DSC1 may be a marker for tumour differentiation, DSC3 has a potential diagnostic value in subclassification of non-small cell lung carcinoma into SCC and ADC, and furthermore, DSC1 and DSC3 may be prognostic markers for lung cancer.

FGFR1 expression and gene copy numbers in human lung cancer.

FGFR1 is a receptor tyrosine kinase of which the ligands belong to the fibroblast growth factor family. To evaluate the significance of FGFR1 in lung cancer, we analysed tumours by immunohistochemistry (IHC) and fluorescence in situ hybridization (FISH). Tissue microarrays were constructed containing 380 lung cancer samples including squamous cell carcinomas (SCC), adenocarcinomas (ADC), non-small cell lung cancer not otherwise specified, metastases, neuroendocrine tumours, large cell lung cancer and small cell lung cancer. FGFR1 expression was analysed by IHC and scored semi-quantitatively by a four-tier approach (0, 1, 2, 3). Using dual-colour interphase FISH with probes specific for the locus on 8p12 and the centromere of chromosome 8 (CEN8), copy numbers of FGFR1 were determined. High expression of FGFR1 was associated with increased FGFR1 gene copy numbers in squamous cell carcinoma (p < 0.001). The FGFR1 locus was equally affected by copy number losses and gains. The higher FGFR1 gene copy numbers in SCC compared to ADC did not reach statistical significance. High copy number amplification of FGFR1 was a very rare event, the FGFR1/CEN8 signal ratio reaching a maximum value of 2.75. There were no significant associations between FGFR1 and clinicopathological parameters. Fibroblast growth factor signalling represents an interesting therapeutic target in lung cancer. However, the pathways are complex with potential oncogenic and anti-oncogenic activities. Our data may help to define criteria for selecting patients that may benefit from these new therapeutic options.

Effects of lattice expansion on the reactivity of a one-dimensional oxide.

By means of scanning tunneling microscopy (STM) and density functional theory (DFT) calculations, we characterize at the single-atom level the mechanism of the water formation reaction on the (10 x 2)-O/Rh(110) surface, a prototype of a one-dimensional (1D) oxide where the lattice expansion and the segmentation of the surface play a fundamental role. When the reaction is imaged in the 238-263 K temperature range (35 s/image acquisition time), a peculiar comblike propagation mechanism for the reaction front is found. Fast STM measurements (33 ms/image) prove that this mechanism holds also at room temperature, being therefore an intrinsic characteristic of the reaction on the 1D oxide. DFT calculations explain the observed behavior as due to the interplay between the lattice expansion in the initial surface and its relaxation during the reaction that leads to varying configurations for the reactants. At low temperatures, the reaction produces, in its final stages, a low-coverage, ordered patterning of the surface with residual oxygen. The pattern formation is related to the segmentation of the oxide phase.

Structure of the ultrathin aluminum oxide film on NiAl(110).

The well-ordered aluminum oxide film formed by oxidation of the NiAl(110) surface is the most intensely studied metal surface oxide, but its structure was previously unknown. We determined the structure by extensive ab initio modeling and scanning tunneling microscopy experiments. Because the topmost aluminum atoms are pyramidally and tetrahedrally coordinated, the surface is different from all Al2O3 bulk phases. The film is a wide-gap insulator, although the overall stoichiometry of the film is not Al2O3 but Al10O13. We propose that the same building blocks can be found on the surfaces of bulk oxides, such as the reduced corundum (0001) surface.