A novel 3D-vision–based collaborative robot as a scope holding system for port surgery: a technical feasibility study

OBJECTIVE A clear, stable, suitably located vision field is essential for port surgery. A scope is usually held by hand or a fixing device. The former yields fatigue and requires lengthy training, while the latter increases inconvenience because of needing to adjust the scope. Thus, the authors innovated a novel robotic system that can recognize the port and automatically place the scope in an optimized position. In this study, the authors executed a preliminary experiment to test this system’s technical feasibility and accuracy in vitro. METHODS A collaborative robotic (CoBot) system consisting of a mechatronic arm and a 3D camera was developed. With the 3D camera and programmed machine vision, CoBot can search a marker attached to the opening of the surgical port, followed by automatic alignment of the scope’s axis with the port’s longitudinal axis so that optimal illumination and visual observation can be achieved. Three tests were conducted. In test 1, the robot positioned a laser range finder attached to the robot’s arm to align the sheath’s center axis. The laser successfully passing through two holes in the port sheath’s central axis defined successful positioning. Researchers recorded the finder’s readings, demonstrating the actual distance between the finder and the sheath. In test 2, the robot held a high-definition exoscope and relocated it to the setting position. Test 3 was similar to test 2, but a metal holder substituted the robot. Trained neurosurgeons manually adjusted the holder. The manipulation time was recorded. Additionally, a grading system was designed to score each image captured by the exoscope at the setting position, and the scores in the two tests were compared using the rank-sum test. RESULTS The CoBot system positioned the finder successfully in all rounds in test 1; the mean height errors ± SD were 1.14 mm ± 0.38 mm (downward) and 1.60 mm ± 0.89 mm (upward). The grading scores of images in tests 2 and 3 were significantly different. Regarding the total score and four subgroups, test 2 showed a more precise, better-positioned, and more stable vision field. The total manipulation time in test 2 was 20 minutes, and for test 3 it was 52 minutes. CONCLUSIONS The CoBot system successfully acted as a robust scope holding system to provide a stable and optimized surgical view during simulated port surgery, providing further evidence for the substitution of human hands, and leading to a more efficient, user-friendly, and precise operation.

Application of 3D cameras to assess the quality of soil cultivation in agriculture

Currently, electronic devices are widely used in modern precision farming technology. Soil surface measurement is solved with single-purpose handheld instruments that are placed in the field before passing a tillage machine such as a plow or harrow and after tilling the soil. Laser, photogravimetric and synthetic aperture radar systems are used for non-contact measurement of soil roughness and uniformity. Measurements to calibrate the camera output were carried out at three height levels: 500 mm, 1000 mm and 1500 mm. The indicated measuring heights have been selected for possible applications in agricultural soil research, for example when determining the quality of the treated soil during plowing after passing the tillage machine. Measurements can be used to determine the condition of the soil before and after treatment. The system is easy to use and does not require special and additional expensive software. The use of 3D cameras is effective for determining the state of soil cultivation and a promising direction for adjusting the parameters of the tillage machine. Keywords: 3D CAMERA; MODEL; UNEVENNESS OF THE SOIL, TILLAGE MACHINE

Therapeutic Effects of Tranexamic Acid Cream in Comparison to Hydroquinone 4% Cream in Treatment of Melasma: A Split Face Comparative Study

Background Melasma is a chronic, acquired pigmentary disorder characterized by gray-brown macules and patches affecting photodistributed part of the face such as the bridge of the nose, cheek, upper lip, forehead, and mandible. It is seen mostly in women of reproductive age group and has an onset usually after pregnancy. However, in around 10% of the cases, males are also affected. Objectives The aim of our study was to assess and compare the therapeutic effects of tranexamic acid cream versus hydroquinone 4% cream in treating patients with melasma. Patients and Methods This prospective split face comparative study included thirty three patients with their age ranging from 18 to 40 years, participated for treatment of different types of melasma, recruited from outpatient clinic of Dermatology department Ain Shams University Hospitals during the period from January to June 2019. The study was approved by the Research Ethical Committee, Faculty of Medicine, Ain Shams University and fulfilled all the ethical aspects required in human research. All patients received full information about description of the procedure of treatment, possible side effects, photo documentation and they all provided informed consent. Results Both topical TA and HQ 4% cream were efficient in treatment of different types of melasma as shown by significant decrease in Hemi MASI score, patient satisfaction score, significant decrease in average level of melanin measured by Antera 3D camera and significant decrease in area % of melanin by histopathological evaluation after 3 months of treatment, although slight recurrence of melasma was observed one month after stopping both treatments. Meanwhile, no significant difference was observed in treatment response of TA and HQ regarding Hemi MASI score, patient satisfaction score, average level of melanin (Antera 3D camera). This could be attributed to the small number of included patients. Conclusion We concluded that the TA appears to be a promising therapeutic option in the treatment of melasma. TA has fewer adverse effects, same or even better results in comparison with other melasma targeting therapies as hydroquinone cream.

Evaluation of the Efficacy of Intense Pulsed Light in Skin Rejuvenation

Background The pathology of skin aging is a very complex process. There are extrinsic and intrinsic factors which contribute to the pathogenesis of skin aging. Intrinsic (chronological) aging is caused by inherited genes, and extrinsic aging caused by many external factors such as exposure to the sun. With increasing age, more people are seeking to maintain the health of their skin and the demand for treatment of aged skin has raised.(1) Aim of the Work To evaluate the efficacy of Intense Pulsed Light in skin rejuvenation with assessment by antera 3D camera. Patients and Methods This study is a single arm interventional study which included 21adult housewives female patients complaining of different signs of facial photodamage, their age ranged between 30 -40 years, recruited from outpatient dermatology clinic of Ain Shams University Hospital, from June 2018 to January 2019. Patients were subjected to 4 sessions of IPL treatments 2 weeks apart for skin rejuvenation. Evaluation of treatment response was done through Global Aesthetic Improvement Scale (GAIS), Antera 3D camera and patient satisfaction score. Results There was highly significant decrease in indentation index of wrinkles, roughness index of skin and average level of melanin (average of whole face) measured by Antera 3D camera after last IPL treatment session (p value=0.001). Conclusion IPL is proven to be safe and elicited a significant skin rejuvenating effect without prolonged downtime.It is effective in treating various manifestations of photodamaged skin, as consistently enchoed by patient satisfaction scores, GAIS and Antera 3D camera results.

Card3DFace—An Application to Enhance 3D Visual Validation in ID Cards and Travel Documents

The identification of a person is a natural way to gain access to information or places. A face image is an essential element of visual validation. In this paper, we present the Card3DFace application, which captures a single-shot image of a person’s face. After reconstructing the 3D model of the head, the application generates several images from different perspectives, which, when printed on a card with a layer of lenticular lenses, produce a 3D visualization effect of the face. The image acquisition is achieved with a regular consumer 3D camera, either using plenoptic, stereo or time-of-flight technologies. This procedure aims to assist and improve the human visual recognition of ID cards and travel documents through an affordable and fast process while simultaneously increasing their security level. The whole system pipeline is analyzed and detailed in this paper. The results of the experiments performed with polycarbonate ID cards show that this end-to-end system is able to produce cards with realistic 3D visualization effects for humans.

LiDAR/ToF Sensor System Based Various Applications: A Review

Abstract— The review article will first introduce the basic concept of LiDAR/ToF (Light detection and ranging based on time of flight) sensor system. Then, numerous applications based on LiDAR/ToF sensor are given in specific fields such as consumer electronics, industrial, smart-city, autonomous vehicles, and space & military. In addition, the technology trends and road map of those products are also discussed in detail. This review will be great references for sales, marketing, and researchers whom plan to work on LiDAR technology. Keywords—Self-driving car, Light distance and ranging, Time of flight, 3D camera.

Influence of breathing state on the accuracy of automated patient positioning in thoracic CT using a 3D camera for body contour detection

Objective To assess the influence of breathing state on the accuracy of a 3D camera for body contour detection and patient positioning in thoracic CT. Materials and methods Patients who underwent CT of the thorax with both an inspiratory and expiratory scan were prospectively included for analysis of differences in the ideal table height at different breathing states. For a subgroup, an ideal table height suggestion based on 3D camera images at both breathing states was available to assess their influence on patient positioning accuracy. Ideal patient positioning was defined as the table height at which the scanner isocenter coincides with the patient’s isocenter. Results The mean (SD) difference of the ideal table height between the inspiratory and the expiratory breathing state among the 64 included patients was 10.6 mm (4.5) (p < 0.05). The mean (SD) positioning accuracy, i.e., absolute deviation from the ideal table height, within the subgroup (n = 43) was 4.6 mm (7.0) for inspiratory scans and 7.1 mm (7.7) for expiratory scans (p < 0.05) when using corresponding 3D camera images. The mean (SD) accuracy was 14.7 mm (7.4) (p < 0.05) when using inspiratory camera images on expiratory scans; vice versa, the accuracy was 3.1 mm (9.5) (p < 0.05). Conclusion A 3D camera allows for accurate and precise patient positioning if the camera image and the subsequent CT scan are acquired in the same breathing state. It is recommended to perform an expiratory planning image when acquiring a thoracic CT scan in both the inspiratory and expiratory breathing state. Key Points • A 3D camera for body contour detection allows for accurate and precise patient positioning if the camera image and the subsequent CT scan are acquired in the same breathing state. • It is recommended to perform an expiratory planning image when acquiring a thoracic CT scan in both the inspiratory and expiratory breathing state.

Validation of a 3D Camera System for Cycling Analysis

Background: Kinematic analysis aimed toward scientific investigation or professional purposes is commonly unaffordable and complex to use. Objective: The purpose of this study was to verify concurrent validation between a cycling-specific 3D camera and the gold-standard 3D general camera systems. Methods: Overall, 11 healthy amateur male triathletes were filmed riding their bicycles with Vicon 3D cameras and the Retul 3D cameras for bike fitting analysis simultaneously. All 18 kinematic measurements given by the bike fitting system were compared with the same data given by Vicon cameras through Pearson correlation (r), intraclass correlation coefficients (ICC), standard error measurements (SEM), and Bland–Altman (BA) analysis. Confidence intervals of 95% are given. Results: A very high correlation between cameras was found on six of 18 measurements. All other presented a high correlation between cameras (between 0.7 and 0.9). In total, six variables indicate a SEM of less than one degree between systems. Only two variables indicate a SEM higher than two degrees between camera systems. Overall, four measures indicate bias tendency according to BA. Conclusions: The cycling-specific led-emitting 3D camera system tested revealed a high or very high degree of correlation with the gold-standard 3D camera system used in laboratory motion capture. In total, 14 measurements of this equipment could be used in sports medicine clinical practice and even by researchers of cycling studies.