To review the latest surgical advances and evolving clinical use of scleral bio-tissue for reinforcement in the eye and review the published literature on novel surgical applications of scleral allograft bio-tissue. Conventional surgical procedures for scleral reinforcement using homologous scleral allograft have been traditionally ab-externo interventions comprising of anterior or posterior reinforcement of the sclera for clinical indications such as trauma, scleromalacia, glaucoma drainage device coverage, scleral perforation, buckle repair as well as posterior reinforcement for pathologic myopia and staphyloma. There have been a few novel ab-interno uses of scleral bio-tissue for reinforcement in both retina and glaucoma. Over the last decade, there has been an increase in peer-reviewed publications on scleral reinforcement, reflecting more interest in its clinical applications. With favorable biological and biomechanical properties, scleral allograft may be an ideal substrate for an array of new applications and surgical uses.

Monte Carlo (MC) simulation for light propagation in scattering and absorbing media is the gold standard for studying the interaction of light with biological tissue and has been used for years in a wide variety of cases. The interaction of photons with the medium is simulated based on its optical properties and the original approximation of the scattering phase function. Over the past decade, with the new measurement geometries and recording techniques invented also the corresponding sophisticated methods for the description of the underlying light-tissue interaction taking into account realistic parameters and settings were developed. Applications, such as multiple scattering, optogenetics, optical coherence tomography, Raman spectroscopy, polarimetry and Mueller matrix measurement have emerged and are still constantly improved. Here, we review the advances and recent applications of MC simulation for the active field of the life sciences and the medicine pointing out the new insights enabled by the theoretical concepts.

The refractive index of blood is a key biophysical parameter, which can reflect the physiological state. We measured the refractive index of whole blood and other components, such as serum, plasma, and hemoglobin, based on internal reflection by using a homemade apparatus in the spectral range of 400 to 750 nm. In addition to the hemoglobin solution, which has a Soret band about 420 nm and two Q-bands between 500 and 600 nm, the measurements of other samples are the normal dispersion curve. The results are approximated by the Cauchy equation and Sellmeier equation, and the correlation coefficients are more than 0.997.

OBJECTIVE: Providing feedback to surgical trainees is a critical component for assessment of technical skills, yet remains costly and time consuming. We hypothesize that statistical selection can identify a homogenous group of nonexpert crowdworkers capable of accurately grading inanimate surgical video.
METHODS: Applicants auditioned by grading 9 training videos using the Objective Structured Assessment of Technical Skills (OSATS) tool and an error-based checklist. The summed OSATS, summed errors, and OSATS summary score were tested for outliers using Cronbach\'s Alpha and single measure intraclass correlation. Accepted crowdworkers then submitted grades for videos in 3 different compositions: full video 1× speed, full video 2× speed, and critical section segmented video. Graders were blinded to this study and a similar statistical analysis was performed.
METHODS: The study was conducted at the University of Pittsburgh Medical Center (Pittsburgh, PA), a tertiary care academic teaching hospital.
METHODS: Thirty-six premedical students participated as crowdworker applicants and 2 surgery experts were compared as the gold-standard.
RESULTS: The selected hire intraclass correlation was 0.717 for Total Errors and 0.794 for Total OSATS for the first hire group and 0.800 for Total OSATS and 0.654 for Total Errors for the second hire group. There was very good correlation between full videos at 1× and 2× speed with an interitem statistic of 0.817 for errors and 0.86 for OSATS. Only moderate correlation was found with critical section segments. In 1 year 275hours of inanimate video was graded costing $22.27/video or $1.03/minute.
CONCLUSIONS: Statistical selection can be used to identify a homogenous cohort of crowdworkers used for grading trainees\' inanimate drills. Crowdworkers can distinguish OSATS metrics and errors in full videos at 2× speed but were less consistent with segmented videos. The program is a comparatively cost-effective way to provide feedback to surgical trainees.

OBJECTIVE: Obtaining the proficiency on the robotic platform necessary to safely perform a robotic pancreatoduodenectomy is particularly challenging. We hypothesize that by instituting a proficiency-based robotic training curriculum we can enhance novice surgeons\' skills outside of the operating room, leading to a shorter learning curve.
METHODS: A biotissue curriculum was designed consisting of sewing artificial organs to simulate a hepaticojejunostomy (HJ), gastrojejunostomy (GJ), and pancreaticojejunostomy (PJ). Three master robotic surgeons performed each biotissue anastomosis to assess validity. Using video review, trainee performance on biotissue drills was evaluated for time, errors and objective structured assessment of technical skills (OSATS) by 2 blinded graders.
METHODS: This study is conducted at the University of Pittsburgh Medical Center (Pittsburgh, PA), a tertiary care academic teaching hospital.
METHODS: In total, 14 surgical oncology fellows completed the biotissue curriculum.
RESULTS: Fourteen fellows performed 196 anastomotic drills during the first year: 66 (HJ), 64 (GJ), and 66 (PJ). The fellows\' performances were analyzed as a group by attempt. The attendings\' first attempt outperformed the fellows\' first attempt in all metrics for every drill (all p < 0.05). More than 5 analyzed attempts of the HJ, there was improvement in time, errors, and OSATS (all p < 0.01); however, no metric reached attending performance. For the GJ, time, errors, and OSATS all improved more than 5 attempts (all p < 0.01), whereas only errors and OSATS reached proficiency. For the PJ, errors and OSATS both improved over attempts (p < 0.01) and reached proficiency; however, time did not statistically improve nor reach proficiency. The graders scoring correlated for errors and OSATS (p < 0.0001).
CONCLUSIONS: A pancreatoduodenectomy biotissue curriculum has face and construct validity. The curriculum is feasible and improves errors and technical performance. Time is the most difficult technical parameter to improve. This curriculum is a valid tool for teaching robotic pancreatoduodenectomies with established milestones for reaching optimum performance.