Correlation between operative time and crowd-sourced skills assessment for robotic bariatric surgery.

INTRODUCTION: Operative time has been traditionally used as a proxy for surgical skill and is commonly utilized to measure the learning curve, assuming that faster operations indicate a more skilled surgeon. The Global Evaluative Assessment of Robotic Skills (GEARS) rubric is a validated Likert scale for evaluating technical skill. We hypothesize that operative time will not correlate with the GEARS score. METHODS: Patients undergoing elective robotic sleeve gastrectomy at a single bariatric center of excellence hospital from January 2019 to March 2020 were captured in a prospectively maintained database. For step-specific scoring, videos were broken down into three steps: ligation of short gastric vessels, gastric transection, and oversewing the staple line. Overall and step-specific GEARS scores were assigned by crowd-sourced evaluators. Correlation between operative time and GEARS score was assessed with linear regression and calculation of the R2 statistic. RESULTS: Sixty-eight patients were included in the study, with a mean operative time of 112 ± 27.4 min. The mean GEARS score was 20.1 ± 0.81. Mean scores for the GEARS subcomponents were: bimanual dexterity 4.06 ± 0.17; depth perception 3.96 ± 0.24; efficiency 3.82 ± 0.19; force sensitivity 4.06 ± 0.20; robotic control 4.16 ± 0.21. Operative time and overall score showed no correlation (R2 = 0.0146, p = 0.326). Step-specific times and scores showed weak correlation for gastric transection (R2 = 0.0737, p = 0.028) and no correlation for ligation of short gastric vessels (R2 = 0.0262, p = 0.209) or oversewing the staple line (R2 = 0.0142, p = 0.344). CONCLUSIONS: Operative time and crowd-sourced GEARS score were not correlated. Operative time and GEARS scores measure different performance characteristics, and future studies should consider using both a validated skills assessment tool and operative time for a more complete evaluation of skill.

Positioning a multifunctional basic helix-loop-helix transcription factor within the Ciona notochord gene regulatory network.

In a multitude of organisms, transcription factors of the basic helix-loop-helix (bHLH) family control the expression of genes required for organ development and tissue differentiation. The functions of different bHLH transcription factors in the specification of nervous system and paraxial mesoderm have been widely investigated in various model systems. Conversely, the knowledge of the role of these regulators in the development of the axial mesoderm, the embryonic territory that gives rise to the notochord, and the identities of their target genes, remain still fragmentary. Here we investigated the transcriptional regulation and target genes of Bhlh-tun1, a bHLH transcription factor expressed in the developing Ciona notochord as well as in additional embryonic territories that contribute to the formation of both larval and adult structures. We describe its possible role in notochord formation, its relationship with the key notochord transcription factor Brachyury, and suggest molecular mechanisms through which Bhlh-tun1 controls the spatial and temporal expression of its effectors.

Does Surgeon Experience Correlate with Crowd-Sourced Skill Assessment in Robotic Bariatric Surgery?

BACKGROUND: The Global Evaluative Assessment of Robotic Skills (GEARS) rubric provides a measure of skill in robotic surgery. We hypothesize surgery performed by more experienced operators will be associated with higher GEARS scores. METHOD: Patients undergoing sleeve gastrectomy from 2016 to 2020 were analyzed. Three groups were defined by time in practice: less than 5, between 5 and 15, and more than 15 years. Continuous variables were compared with ANOVA and multivariable regression was performed. RESULTS: Fourteen operators performing 154 cases were included. More experienced surgeons had higher GEARS scores and shorter operative times. On multivariable regression, operative time (P = 0.027), efficiency (P = .022), depth perception (P = 0.033), and bimanual dexterity (P = 0.047) were associated with experience. CONCLUSIONS: In our video-based assessment (VBA) model, operative time and several GEARS subcomponent scores were associated with surgical experience. Further studies should determine the association between these metrics and surgical outcomes.

Xbp1 and Brachyury establish an evolutionarily conserved subcircuit of the notochord gene regulatory network.

Gene regulatory networks coordinate the formation of organs and structures that compose the evolving body plans of different organisms. We are using a simple chordate model, the Ciona embryo, to investigate the essential gene regulatory network that orchestrates morphogenesis of the notochord, a structure necessary for the proper development of all chordate embryos. Although numerous transcription factors expressed in the notochord have been identified in different chordates, several of them remain to be positioned within a regulatory framework. Here, we focus on Xbp1, a transcription factor expressed during notochord formation in Ciona and other chordates. Through the identification of Xbp1-downstream notochord genes in Ciona, we found evidence of the early co-option of genes involved in the unfolded protein response to the notochord developmental program. We report the regulatory interplay between Xbp1 and Brachyury, and by extending these results to Xenopus, we show that Brachyury and Xbp1 form a cross-regulatory subcircuit of the notochord gene regulatory network that has been consolidated during chordate evolution.