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The incidence of facial skin cancer increases worldwide, resulting in more surgical resections and reconstructions. Reconstructive surgery aims to approach a normal facial anatomy to optimize the quality of life. Objective automated assessment of the esthetic outcome of facial reconstructions could provide feedback for the improvement of surgical techniques and preoperative patient expectation management. This systematic literature review aimed to assess whether modern technologies can create automated objective measurements of surgical and non-surgical facial interventions outcomes using 3D surface imaging technology. A systematic literature search was conducted in Embase, Medline (Ovid), Web of Science, and Cochrane on May 19, 2021. All English literature was collected on surgical and non-surgical invasive facial interventions in which 3D surface imaging technology was used for objective automated assessment of outcomes. Fourteen articles were included in the systematic review. 3D surface imaging technology and automated assessment techniques were found for skin malignancy, cleft lip repair, rhinoplasty, orthognathic surgery, and injectables. Ten 3D surface imaging technology hardware systems and 12 software systems were described. Four studies compared 3D surface imaging techniques to conventional methods. Ten studies used 3D surface imaging techniques for the evaluation of the surgical outcome, without comparison to 2D photography, validated scores, or a panel. Two studies validated the hardware system. This systematic literature review shows that 3D surface imaging technology has the potential for automated objective assessment of facial intervention outcomes. Future studies are necessary to study and validate these tools for standard clinical use in patients with facial interventions. [ABSTRACT FROM AUTHOR]

Breast volume estimation and implant size are crucial factors to achieve a symmetrical result in esthetic and reconstructive breast surgery. Although three-dimensional surface imaging (3DSI) has allowed for a better understanding of breast shape, size, and asymmetry during patient consultation, its use has been limited regarding intraoperative decision-making. To validate the intraoperative use of a portable hand-held 3D surface imaging device as an objective tool to assess volumetric changes during breast augmentation surgery. Patients receiving bilateral, submuscular breast augmentation were enrolled for this study. Intraoperative 3DSI was conducted using the Sense 3D scanner, allowing for digitalization of the operating field. Intraoperatively gauged volume changes caused by known implant volumes were compared with digital measurements calculated from 3D surface images of the operating field. Digital intraoperative breast volumes were compared to the pre- and postoperative Vectra XT reference system. Eighty individual breasts of 40 patients were successfully 3D imaged before incision and after wound closure. There was no significant difference between digital breast volumes by intraoperative and outpatient 3DSI. Intraoperative pre- to postoperative 3D breast volume change showed no significant difference to the known implant volume (p = 0.124, mean deviation of 5.8 ± 24.3 mL and 2.0 ± 9.0%). Our findings showed a high correlation regarding intraoperative digital breast volumetric changes. Intraoperative use of 3DSI yielded objective data during breast augmentation. This novel technique could beneficially impact future breast implant selection, especially in cases with breast asymmetry and the need for differently sized implants. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) surface-imaging is an increasingly popular and useful tool in surgical planning and evaluation. These systems are used for anthropometric measurements of the face, breast and upper extremity. Its accuracy has, however, not yet been evaluated for the thigh. This could prove useful in the evaluation of autologous breast reconstructions using fasciocutaneous tissue of the thigh, such as the profunda artery perforator (PAP) flap. Thirty-five patients who underwent PAP flap surgery and 35 healthy controls were included. Thigh circumferences were measured using a flexible measuring tape at pre-defined levels. 3D images of the thigh were taken with the Canfield Vectra XT and fused to create 3D reconstructions. 3D circumferences were measured using the Vectra Analysis Module. Measuring tape and 3D circumferences were compared for mutual agreement. Thigh circumference measurements by measuring tape correlated excellently with 3D measurements (r = 0.999). Bland-Altman plots demonstrated good agreement with a mean difference of -1.2 mm between the measuring tape and 3D measurements. The mean relative difference of both methods was −0.24%. Paired t-tests showed no significant statistical differences between the measuring tape and 3D circumference measurements in legs that underwent PAP flap surgery and without. Flexible measuring tape and 3D circumference measurements of the thigh show excellent correlation. Three-dimensional surface imaging can thus be used to measure thigh circumferences in both patients with and without prior surgery of the thigh. [ABSTRACT FROM AUTHOR]

To conduct a direct comparison regarding the non-coplanar positioning accuracy between the optical surface imaging system Catalyst HDTM and non-coplanar cone-beam computed tomography (NC-CBCT) in intracranial single-isocentre non-coplanar stereotactic radiosurgery (SRS) and hypofractionated stereotactic radiotherapy (HSRT). Twenty patients with between one and five brain metastases who underwent single-isocentre non-coplanar volumetric modulated arc therapy (NC-VMAT) SRS or HSRT were enrolled in this study. For each non-zero couch angle, both Catalyst HDTM and NC-CBCT were used for set-up verification prior to beam delivery. The set-up error reported by Catalyst HDTM was compared with the set-up error derived from NC-CBCT, which was defined as the gold standard. Additionally, the dose delivery accuracy of each non-coplanar field after using Catalyst HDTM and NC-CBCT for set-up correction was measured with SRS MapCHECKTM. The median set-up error differences (absolute values) between the two positioning methods were 0.30 mm, 0.40 mm, 0.50 mm, 0.15°, 0.10° and 0.10° in the vertical, longitudinal, lateral, yaw, pitch and roll directions, respectively. The largest absolute set-up error differences regarding translation and rotation were 1.5 mm and 1.1°, which occurred in the longitudinal and yaw directions, respectively. Only 35.71% of the pairs of measurements were within the tolerance of 0.5 mm and 0.5° simultaneously. In addition, the non-coplanar field with NC-CBCT correction yielded a higher gamma passing rate than that with Catalyst HDTM correction (P < 0.05), especially for evaluation criteria of 1%/1 mm with a median increase of 12.8%. Catalyst HDTM may not replace NC-CBCT for non-coplanar set-up corrections in single-isocentre NC-VMAT SRS and HSRT for single and multiple brain metastases. The potential role of Catalyst HDTM in intracranial SRS/HSRT needs to be further studied in the future. • Focusing on non-coplanar set-up correction in single-isocentre non-coplanar SRS/HSRT. • Direct non-coplanar positioning accuracy comparison between Catalyst HDTM and non-coplanar CBCT. • Only 35.71% of the absolute set-up error difference between Catalyst HDTM and non-coplanar CBCT was within 0.5 mm/0.5°. • Non-coplanar VMAT using non-coplanar CBCT yields higher delivery accuracy than non-coplanar VMAT using Catalyst HDTM. [ABSTRACT FROM AUTHOR]

The use of optical surface imaging systems (OSISs) is increasingly becoming popular in radiotherapy practice, especially during breast cancer treatment. This study reviews the accuracy of the available commercial OSISs for breast radiotherapy. A literature search was conducted and identified the available commercial OSISs from different manufacturers which are integrated into radiotherapy practice for setup verification during breast radiotherapy. Studies that evaluated the accuracy of the OSISs during breast radiotherapy using cone beam computed tomography (CBCT) as a reference were retrieved and analysed. The physics and working principles of the systems from each manufacturer were discussed together with their respective strength and limitations. A total of five (5) different commercially available OSISs from four (4) manufacturers were identified each with a different working principle. Six (6) studies were found to evaluate the accuracy of the systems during breast radiotherapy in conjunction with CBCT as a goal standard. The studies revealed that the accuracy of the systems in terms of mean difference ranges from 0.1 to 2.1 mm. The correlation between CBCT and OSIS ranges between 0.4 and 0.9. The limit of agreements obtained using Bland Altman analysis in the studies was also within acceptable range. The OSISs have an acceptable level of accuracy and could be used safely during breast radiotherapy. The systems are non-invasive, ionising radiation-free free, and provide real-time imaging of the target surface at no extra concomitant imaging dose. However, the system should only be used to complement rather than replace x-ray-based image guidance techniques such as CBCT. [ABSTRACT FROM AUTHOR]

• Study of surface and diaphragm motion during deep inspiration breath hold (DIBH). • Diaphragm tracking on kV projections. • Limited surface and diaphragm motion association, with noted study constraints. Surface-guided imaging (SGI) is increasingly utilized to monitor patient motion during deep inspiration breath hold (DIBH) in radiotherapy. Understanding the association between surface and internal motion is crucial for effective monitoring. To investigate the relation between motion detected by SGI using surface-guided radiotherapy (SGRT) and internal motion measured through diaphragm tracking on kV projections acquired with DIBH for online CBCT. Both SGI and kV were simultaneously acquired for ten patients over a total of 200 breath holds (BH). Diaphragm tracking was performed using second-degree polynomial curve fitting on the derivative images for each kV projection and high-pass filtering at 1/30 Hz to remove rotational effects. The superior-inferior (SI) and anterior-posterior (AP) motions of SGI were then compared to kV tracking using various statistical measures. The correlation (individuals' median: −0.07 to 0.73) was a suboptimal metric for the BH data. The median and 95th percentile absolute differences between SGI-SI and kV were 0.73 mm and 3.46 mm, respectively, during DIBH. For SGI-AP, the corresponding values were 0.55 mm and 2.80 mm. For inter-BH measurements, the contingency table based on a 3 mm threshold indicated surface/diaphragm motion agreement for SGI-SI/kV and SGI-AP/kV was 61 % and 56 %, respectively. Both intra- and inter-BH measurements indicated a limited association between surface and diaphragm motion, with certain constraints noted due to kV tracking and DIBH data. These findings warrant further investigation into the association between surface and internal motion. [ABSTRACT FROM AUTHOR]

To evaluate the impact of Varian Identify, a novel combined radiofrequency identification, biometric and surface-matching technology, on its potential for patient safety and prevention of radiation therapy treatment deviations. One hundred eight radiation therapy treatment deviation reports at our facility over the past 8 years were analyzed. Three major categories were defined based on the time point of occurrence: physician order deviations (19.4%), treatment-planning deviations (24.1%), and machine treatment deviations (56.5%). The impact of Identify on potential prevention of machine treatment deviations was analyzed. A failure mode and effects analysis was performed on the 5 most frequently occurring errors preventable with Identify. Safety analysis of the Identify system was reported based on 3.5 years of clinical data post-Identify system installation on 3 treatment vaults. Of the 61 machine treatment deviations, 47 (77%) were interpreted as being preventable by using Identify. Our failure mode and effects analysis showed reductions in all risk priority numbers post-Identify application. Safety analysis of the Identify system from our direct observation that for approximately 7 cumulative years of Identify use in 3 different treatment vaults, where 9 deviations would have been expected to occur over this combined period, zero machine treatment events occurred. The combination of Identify biometric, radiofrequency identification, and surface-matching technologies was observed to enable an effective process for enhancing safety and efficiency of radiation therapy treatment. A significant reduction in machine-related deviations was observed. [ABSTRACT FROM AUTHOR]

To evaluate pectus excavatum, 3-dimensional surface imaging is a promising radiation-free alternative to computed tomography and plain radiographs. Given that 3-dimensional images concern the external surface, the conventional Haller index, and correction index are not applicable as these are based on internal diameters. Therefore, external equivalents have been introduced for 3-dimensional images. However, cut-off values to help determine surgical candidacy using external indices are lacking. A prospective cohort study was conducted. Consecutive patients referred for suspected pectus excavatum received a computed tomography (≥18 years) or plain radiographs (<18 years). The external Haller index and external correction index were calculated from additionally acquired 3-dimensional images. Cut-off values for the 3-dimensional image derived indices were obtained by receiver-operating characteristic curve analyses, using a conventional Haller index ≥3.25, and computed tomography derived correction index ≥28.0% as indicative for surgery. Sixty-one and 63 patients were included in the computed tomography and radiograph group, respectively. To determine potential surgical candidacy, receiver-operating characteristic analyses found an optimum cut-off of ≥1.83 for the external Haller index in both the computed tomography and radiograph group with a positive predictive value between 0.90 and 0.97 and a negative predictive value between 0.72 and 0.81. The optimal cut-off for the external correction index was ≥15.2% with a positive predictive value of 0.86 and negative predictive value of 0.93. The 3-dimensional image derived external Haller index and external correction index are accurate radiation-free alternatives to facilitate surgical decision-making among patients suspected of pectus excavatum with values of ≥1.83 and ≥15.2% indicative for surgery. [ABSTRACT FROM AUTHOR]

Abstract Objective Three dimensional (3D) surface imaging is a viable alternative to traditional body morphology measures, but the feasibility of using this technique with people with obesity has not been fully established. Therefore, the aim of this study was to investigate the validity, repeatability and acceptability of a consumer depth camera 3D surface imaging system in imaging people with obesity. Methods The concurrent validity of the depth camera based system was investigated by comparing measures of mid-trunk volume to a gold-standard. The repeatability and acceptability of the depth camera system was assessed in people with obesity at a clinic. Results There was evidence of a fixed systematic difference between the depth camera system and the gold standard but excellent correlation between volume estimates (r2 = 0.997), with little evidence of proportional bias. The depth camera system was highly repeatable – low typical error (0.192 L), high intraclass correlation coefficient (>0.999) and low technical error of measurement (0.64%). Depth camera based 3D surface imaging was also acceptable to people with obesity. Conclusion It is feasible (valid, repeatable and acceptable) to use a low cost, flexible 3D surface imaging system to monitor the body size and shape of people with obesity in a clinical setting. [ABSTRACT FROM AUTHOR]

Optical surface imaging is a nonradiographic, noninvasive technology for continuous localization of patients during radiation therapy. Surface-guided radiation therapy (SGRT) has been applied to many treatment sites including breast, intracranial, head and neck, and extremities. SGRT enables a reduction of initial setup variability, provides verification of immobilization continuously during treatment including at noncoplanar linac gantry angles, and provides dynamic surface information for use in gated and breath-hold treatment techniques, all of which can permit reductions in the margins required to account for target localization uncertainty. Ancillary benefits from surface imaging include the ability to use immobilization techniques that confer greater comfort to patients, a reduction in imaging dose through reduced radiographic localization requirements, and improvements to the speed, efficiency, and safety of clinical workflows. This review will describe the objectives of SGRT, review the commercially available surface imaging systems, and provide an overview of SGRT applications by treatment site. Limitations and future applications of surfacing imaging systems are also discussed. [ABSTRACT FROM AUTHOR]

Optical coherence tomography (OCT) is an imaging technique which can provide sub-surface evaluation of defects in optically compliant components such as those manufactured by polymeric selective laser sintering. In OCT systems, achieving lateral imaging resolutions of <10 µm means that full-depth imaging requires multiple scans due to the limited depth of focus (DOF). We present a study on the application of 'non-diffracting' Bessel beams to extend system DOF and enable deeper imaging with a single scan. Such capability expands the potential for OCT as a rapid tool for sub-surface assessment, either in-line or in-process, by greatly reducing acquisition times. [ABSTRACT FROM AUTHOR]

Combining WO 3 with suitable materials to form heterojunction is essential to overcome the limitations of WO 3 to enhance its photoelectrochemical (PEC) water splitting activity. Moreover, a clear understanding of photo-response and charge behavior of materials could lead to the rational design of efficient photoelectrodes. Given this, an efficient strategy is applied to fabricate WO 3 heterojunction with nitrogen-doped carbon dots (NCDs) and in-depth characterization to investigate the surface charge dynamics using nano imaging in a relation to the enhanced PEC water splitting activity. The optimized NCDs loading to the WO 3 NRs exhibited the enhanced photocurrent density of 1.54 mA cm−2 at 1.23V vs RHE under AM 1.5 G illumination, highest IPCE of ~82 % (at 308.32 nm). The Kelvin probe force microscopy and electrostatic force microscopy reveal that after loading NCDs to the WO 3 , a relatively smooth charge transport has been observed, which improves the PEC. Furthermore, this work demonstrates the effect of photogenerated charges caused by the NCDs that assist in enhancing the increased photocurrent, hydrogen production efficiency, and stability of the PEC water splitting system. Significantly, the nano imaging characterization utilized in this work could be extended to various photoanodes to study the surface charge dynamics. [Display omitted] • WO 3 NRs/NCDs heterojunction was proposed for water splitting applications. • NCD on WO 3 suppresses charge recombination and decreases charge transfer resistance. • Enhanced photocurrent, IPCE, and H 2 production was achieved upon NCD sensitization. • Nanoscale surface imaging was performed to understand insights of carrier dynamics. [ABSTRACT FROM AUTHOR]

• A novel high-speed 3D surface imaging technique using deep learning is proposed. • The phase can be extracted from a single fringe image accurately. • In contrast to Fourier-transform methods, phase accuracy can be improved by near 50. • 3D results of this method can be comparable to the one with phase-shifting methods. How to obtain object information as rich as possible, with the highest possible speed and accuracy from recorded optical signals, has been a crucial issue to the pursuit of powerful imaging technologies. Nowadays, the speed of ultra-fast photography can exceed one quadrillion. However, it can record only two-dimensional images which lack the depth information, greatly limiting our ability to perceive and to understand the complex real-world objects. Inspired by recent successes of deep learning methods in computer vision, we present a novel high-speed three-dimensional (3D) surface imaging approach named micro deep learning profilometry (μ DLP) using the structured light illumination. With a properly trained deep neural network, the phase information is predicted from a single fringe image and then can be converted into the 3D shape. Our experiments demonstrate that μ DLP can faithfully retrieve the geometry of dynamic objects at 20,000 frames per second. Moreover, comparative results show that μ DLP has superior performance in terms of the phase accuracy, reconstruction efficiency, and the ease of implementation over widely used Fourier-transform-based fast 3D imaging techniques, verifying that μ DLP is a powerful high-speed 3D surface imaging approach. [ABSTRACT FROM AUTHOR]

We demonstrate the effectiveness of total focusing methods (TFM) using Rayleigh waves for surface and sub-surface nondestructive inspection of different metals. The relatively low velocity of Rayleigh waves leads to sub-100 μm resolution imaging, with a penetration depth approximately equal to its wavelength. This allows for imaging and sizing sub-millimetric holes, possibly on coated material, as well as cracks, segregations, and other defects. The waves can propagate over long distances and works with curved surfaces or very close to edges. This shows potential for a new type of real-time surface inspection of large surfaces, with excellent spatial resolution. The process is free of chemical preparation and cleaning, and can be fully automated, from acquisition to decision or for making surface digital twin. [ABSTRACT FROM AUTHOR]

• First clinical evaluation of Identify system. • Large pool of 201 patients. • Detailed workflow design. • SGRT system accuracy. To evaluate and characterize the overall clinical functionality and workflow of the newly released Varian Identify system (version 2.3). Three technologies included in the Varian Identify system were evaluated: patient biometric authentication, treatment accessory device identification, and surface-guided radiation therapy (SGRT) function. Biometric authentication employs a palm vein reader. Treatment accessory device verification utilizes two technologies: device presence via Radio Frequency Identification (RFID) and position via optical markers. Surface-guidance was evaluated on both patient orthopedic setup at loading position and surface matching and tracking at treatment isocenter. A phantom evaluation of the consistency and accuracy for Identify SGRT function was performed, including a system consistency test, a translational shift and rotational accuracy test, a pitch and roll accuracy test, a continuous recording test, and an SGRT vs Cone-Beam CT (CBCT) agreement test. 201 patient authentications were verified successfully with palm reader. All patient treatment devices were successfully verified for their presences and positions (indexable devices). The patient real-time orthopedic pose was successfully adjusted to match the reference surface captured at simulation. SGRT-reported shift consistency against couch readout was within (0.1 mm, 0.030). The shift accuracy was within (0.3 mm, 0.10). In continuous recording mode, the maximum variation was 0.2 ± 0.12 mm, 0.030 ± 0.020. The difference between Identify SGRT offset and CBCT was within (1 mm, 10). This clinical evaluation confirms that Identify accurately functions for patient palm identification and patient treatment device presence and position verification. Overall SGRT consistency and accuracy was within (1 mm, 10), within the 2 mm criteria of AAPM TG302. [ABSTRACT FROM AUTHOR]

3D digital surface imaging (digital stereophotogrammetry or “3D photography”) is becoming an increasingly popular tool for quantification of the face, in clinical contexts as well as for research. The modality is easy to apply and is free from motion artifacts and harmful radiation. It is an obvious choice for comprehensive documentation and analysis of facial development and treatment progression and outcome in individuals with juvenile idiopathic arthritis (JIA). An acquisition protocol for 3D digital surface imaging of children and adolescents with JIA using a 3dMDtrio stereophotogrammetric system is presented. Methodology for processing and analysis of the acquired surfaces is presented and applied to two patient cases in order to illustrate quantification of facial development and asymmetry progression. It is concluded that surface imaging is a powerful technique for monitoring of facial development and treatment outcome, and it is proposed that the method would be suitable for multi-center comparisons of treatment outcomes. [ABSTRACT FROM AUTHOR]

A deep learning (DL)-based, deformable registration-driven liver tumor localization technique was developed for onboard deformable motion tracking. The technique (Surf-X360-Bio) uses in-room optical surface imaging and an x-ray projection at an arbitrary scan angle to solve volumetric liver and liver tumor motion in real-time. Surf-X360-Bio solves the volumetric motion of the liver and localizes the liver tumor, through deforming liver and liver tumor meshes segmented on prior 4D-CTs/CBCTs. It uses real-time onboard information from an optical surface image and a simultaneously-acquired x-ray projection (from an arbitrary scan angle). Surf-X360-Bio localizes tumors via two steps: liver boundary motion estimation and intra-liver motion derivation. Surf-X360-Bio first estimates liver boundary motion by a patient-specific surface imaging model (Surf), utilizing the correlation between the external body surface motion and the internal liver boundary motion. As the correlation can be imperfect, the residual motion estimation errors were corrected by a patient-specific, angle-agnostic x-ray imaging model (X360). X360 deformed the liver boundary to match motion-related imaging features encoded in an arbitrarily-angled x-ray projection, using the Surf output for initialization. X360 adopted a geometry-aware learning module to extract and adapt to angle-varying features of arbitrarily-angled x-ray images, by calculating the projection system matrix of each x-ray image on-the-fly during model training and inference. After the liver boundary motion estimation by Surf and X360 , intra-liver deformation was solved by a biomechanical model (Bio) to propagate the liver boundary motion inside to localize the tumors. The DL-based Bio model used domain knowledge of tissue biomechanics and finite element analysis (FEA) to solve intra-liver motion, with a much faster speed than conventional FEA methods to meet the real-time constraint. Surf-X360-Bio was evaluated using a dataset of 34 liver patients. Liver tumor localization accuracy was evaluated by the Dice similarity coefficient (DSC), the 95-percentile Hausdorff distance (HD95), and the center-of-mass error (COME). Using 3,306 motion scenarios spanning the 360 degree x-ray scan angles for each testing patient, Surf-X360-Bio localized the liver tumors to 0.81 (mean) ± 0.16 (s.d.) in DSC, 2.5 ± 1.7 mm in HD95, and 2.1 ± 1.8 mm in COME. In comparison, the prior reference image without deformable registration-driven localization yielded 0.42 ± 0.29 in DSC, 8.1 ± 5.2 mm in HD95, and 8.5 ± 5.2 mm in COME. Via Surf-X360-Bio , the overall inference time was below 230 ms for each case. Combining optical surface imaging and x-ray imaging, Surf-X360-Bio achieved fast (<250 ms inference time), accurate (mean error < 2.1 mm), and robust liver tumor localizations at arbitrary x-ray scan angles for real-time, marker-less 3D deformable motion tracking. [ABSTRACT FROM AUTHOR]

Three-dimensional surface imaging (3D-SI) is being marketed as a tool in aesthetic breast surgery. It has recently also been studied in the objective evaluation of cosmetic outcome of oncological procedures. The aim of this review is to summarise the use of 3D-SI in oncoplastic, reconstructive and aesthetic breast surgery. An extensive literature review was undertaken to identify published studies. Two reviewers independently screened all abstracts and selected relevant articles using specific inclusion criteria. Seventy two articles relating to 3D-SI for breast surgery were identified. These covered endpoints such as image acquisition, calculations and data obtainable, comparison of 3D and 2D imaging and clinical research applications of 3D-SI. The literature provides a favourable view of 3D-SI. However, evidence of its superiority over current methods of clinical decision making, surgical planning, communication and evaluation of outcome is required before it can be accepted into mainstream practice. [ABSTRACT FROM AUTHOR]

We highlight the impact of Ultrahigh Vacuum (UHV)-born surface science on modern electrocatalysis. The microscopic, atomic level picture of surface adsorption and reaction, which was developed in the surface science community in decades of systematic research on single crystals in UHV, has meanwhile become state-of-the-art also in electrochemistry. For the example of CO on Pt(111) single crystals, which has been extensively studied at the solid/gas and the solid/liquid interface using atomic resolution scanning tunnelling microscopy (STM), we highlight how both interfaces may have even more in common than often assumed. We then illustrate how planar model surfaces such as mono- and bimetallic single crystals and surface alloys, prepared and thoroughly analysed in UHV, enabled a systematic search for improved electrocatalysts. Surface alloys, thermodynamically more stable than foreign metal islands, are a particularly important sub-group of model surfaces, which so far have only been fabricated in UHV. We also flag that model surfaces may not always assume the structure anticipated for the respective experiment, regardless of their preparation in UHV or by electrochemical methods. “Accidental” surface alloying may be more common than often assumed, leading to misinterpretations of the structure-property relationships targeted in many model studies. We highlight that controlled surface alloy formation should be a key step in any model study looking at bimetallic systems in order to get an idea what the effect of unintended alloying could possibly be, and to cross-check whether alloyed surfaces may potentially be the better electrocatalysts in the first place. [ABSTRACT FROM AUTHOR]

Summary: Background: In recent decades, three-dimensional (3D) surface-imaging technologies have gained popularity worldwide, but because most published articles that mention them are technical, clinicians often have difficulties gaining a proper understanding of them. This article aims to provide the reader with relevant information on 3D surface-imaging systems. In it, we compare the most recent technologies to reveal their differences. Methods: We have accessed five international companies with the latest technologies in 3D surface-imaging systems: 3dMD, Axisthree, Canfield, Crisalix and Dimensional Imaging (Di3D; in alphabetical order). We evaluated their technical equipment, independent validation studies and corporate backgrounds. Results: The fastest capturing devices are the 3dMD and Di3D systems, capable of capturing images within 1.5 and 1 ms, respectively. All companies provide software for tissue modifications. Additionally, 3dMD, Canfield and Di3D can fuse computed tomography (CT)/cone-beam computed tomography (CBCT) images into their 3D surface-imaging data. 3dMD and Di3D provide 4D capture systems, which allow capturing the movement of a 3D surface over time. Crisalix greatly differs from the other four systems as it is purely web based and realised via cloud computing. Conclusion: 3D surface-imaging systems are becoming important in today's plastic surgical set-ups, taking surgeons to a new level of communication with patients, surgical planning and outcome evaluation. Technologies used in 3D surface-imaging systems and their intended field of application vary within the companies evaluated. Potential users should define their requirements and assignment of 3D surface-imaging systems in their clinical as research environment before making the final decision for purchase. [Copyright &y& Elsevier]

Abstract: Purpose: To evaluate the impact of 3-dimensional (3D) surface imaging on daily patient setup for breast radiotherapy. Materials and Methods: Fifty patients undergoing treatment for whole breast radiotherapy were setup daily using an AlignRT system (VisionRT, London, UK) for 3D surface-based alignment. Daily alignments were performed against a reference surface topogram and shifts from skin marks were recorded daily. This investigation evaluated the following: (1) the performance of the surface-based imaging system for daily breast alignment; (2) the absolute displacements between setup with skin marks and setup with the surface-based imaging system; and (3) the dosimetric effect of daily alignments with skin marks versus surface-based alignments. Results: Displacements from 1258 treatment fractions were analyzed. Sixty percent of those fractions (749) were reviewed against MV portal imaging in order to assess the performance of the AlignRT system. Daily setup errors were given as absolute displacements, comparing setup marks against shifts determined using the surface-based imaging system. Averaged over all patients, the mean displacements were 4.1 ± 2.6 mm, 2.7 ± 1.4 mm, and 2.6 ± 1.2 mm in the anteroposterior (AP), superoinferior (S/I), and left-right (L/R) directions, respectively. Furthermore, the standard deviation of the random error (σ) was 3.2 mm, 2.2 mm, and 2.2 mm in the A/P, S/I, and L/R directions, respectively. Conclusions: Daily alignment with 3D surface imaging was found to be valuable for reducing setup errors when comparing with patient alignment from skin marks. The result of the surface-based alignments specifically showed that alignment with skin marks was noticeably poor in the anteroposterior directions. The overall dosimetric effect of the interfractional variations was small, but these variations showed a potential for increased dose deposition to both the heart and lung tissues. Although these interfractional variations would not negatively affect the quality of patient care for whole breast radiotherapy, it may require an increase in PTV margin, especially in cases of partial breast irradiation. [Copyright &y& Elsevier]