INTRODUCTION AND STUDY AIM: Natural orifice translumenal endoscopic surgery (NOTES) is an emergin... more INTRODUCTION AND STUDY AIM: Natural orifice translumenal endoscopic surgery (NOTES) is an emerging surgical technique that requires a cautious adoption approach to ensure patient safety. High-fidelity virtual-reality-based simulators allow development of new surgical procedures and tools and train medical personnel without risk to human patients. As part of a project funded by the National Institutes of Health, we are developing the virtual transluminal endoscopic surgery trainer (VTEST™) for this purpose. The objective of this study is to conduct a structured needs analysis to identify the design parameters for such a virtual-reality-based simulator for NOTES. METHODS: A 30-point questionnaire was distributed at the 2011 National Orifice Surgery Consortium for Assessment and Research meeting to obtain responses from experts. Ordinal logistic regression and the Wilcoxon rank-sum test were used for analysis. RESULTS: A total of 22 NOTES experts participated in the study. Cholecystect...
ABSTRACT Probe geometry can significantly influence the performances of functional near-infrared ... more ABSTRACT Probe geometry can significantly influence the performances of functional near-infrared spectroscopy applications. This in silico work presents a novel approach for probe placement optimization based on the minimization of sensitivity curvature.
Studies in health technology and informatics, 2013
This study shows task analysis results for the suturing task in the hybrid rigid scope Natural Or... more This study shows task analysis results for the suturing task in the hybrid rigid scope Natural Orifice Translumenal Endoscopic Surgery (NOTES) cholecystectomy procedure. A hierarchical task analysis tree was constructed from the video recordings of the NOTES procedure and time analysis for the suturing subtask was performed. Results indicate that the "Pull Suture Through" subtask requires the greatest time (25.4 sec) and the "Re-bite" subtask had the highest variation (6.6 sec). Intra-rater reliability test (k = 0.68) also showed consistency of the results obtained from the video motion analysis.
Studies in health technology and informatics, 2014
This study investigates the sensitivity of fiber placement positioning for the purpose of prefron... more This study investigates the sensitivity of fiber placement positioning for the purpose of prefrontal cortex imaging using functional near-infrared spectroscopy (fNIRS). Results indicate that our proposed optode placement has higher scaled-absorption sensitivity than the traditional International 10-20 system for optode placement based on Monte Carlo simulations.
A virtual reality-based simulator for natural orifice translumenal endoscopic surgery (NOTES) pro... more A virtual reality-based simulator for natural orifice translumenal endoscopic surgery (NOTES) procedures may be used for training and discovery of new tools and procedures. Our previous study (Sankaranarayanan et al. in Surg Endosc 27:1607-1616, 2013) shows that developing such a simulator for the transvaginal cholecystectomy procedure using a rigid endoscope will have the most impact on the field. However, prior to developing such a simulator, a thorough task analysis is necessary to determine the most important phases, tasks, and subtasks of this procedure. 19 rigid endoscope transvaginal hybrid NOTES cholecystectomy procedures and 11 traditional laparoscopic procedures have been recorded and de-identified prior to analysis. Hierarchical task analysis was conducted for the rigid endoscope transvaginal NOTES cholecystectomy. A time series analysis was conducted to evaluate the performance of the transvaginal NOTES and laparoscopic cholecystectomy procedures. Finally, a comparison of electrosurgery-based errors was performed by two independent qualified personnel. The most time-consuming tasks for both laparoscopic and NOTES cholecystectomy are removing areolar and connective tissue surrounding the gallbladder, exposing Calot's triangle, and dissecting the gallbladder off the liver bed with electrosurgery. There is a positive correlation of performance time between the removal of areolar and connective tissue and electrosurgery dissection tasks in NOTES (r = 0.415) and laparoscopic cholecystectomy (r = 0.684) with p < 0.10. During the electrosurgery task, the NOTES procedures had fewer errors related to lack of progress in gallbladder removal. Contrarily, laparoscopic procedures had fewer errors due to the instrument being out of the camera view. A thorough task analysis and video-based quantification of NOTES cholecystectomy has identified the most time-consuming tasks. A comparison of the surgical errors during electrosurgery gallbladder dissection establishes that the NOTES procedure, while still new, is not inferior to the established laparoscopic procedure.
Studies in health technology and informatics, 2013
Natural orifice translumenal endoscopic surgery (NOTES) is an experimental surgical technique wit... more Natural orifice translumenal endoscopic surgery (NOTES) is an experimental surgical technique with benefits including reduced pain, post operative recovery period and better cosmesis compared to traditional laparoscopic procedures. In a pure NOTES procedure, a flexible endoscope is used for performing the surgery and visualization. The Virtual Translumenal Endoscopic Surgical Trainer (VTEST(TM)) is being developed as a platform to train for NOTES procedures and innovate NOTES tools and techniques. In this work we report the design specification for the hardware interface to be used for VTEST(TM).
INTRODUCTION AND STUDY AIM: Natural orifice translumenal endoscopic surgery (NOTES) is an emergin... more INTRODUCTION AND STUDY AIM: Natural orifice translumenal endoscopic surgery (NOTES) is an emerging surgical technique that requires a cautious adoption approach to ensure patient safety. High-fidelity virtual-reality-based simulators allow development of new surgical procedures and tools and train medical personnel without risk to human patients. As part of a project funded by the National Institutes of Health, we are developing the virtual transluminal endoscopic surgery trainer (VTEST™) for this purpose. The objective of this study is to conduct a structured needs analysis to identify the design parameters for such a virtual-reality-based simulator for NOTES. METHODS: A 30-point questionnaire was distributed at the 2011 National Orifice Surgery Consortium for Assessment and Research meeting to obtain responses from experts. Ordinal logistic regression and the Wilcoxon rank-sum test were used for analysis. RESULTS: A total of 22 NOTES experts participated in the study. Cholecystect...
ABSTRACT Probe geometry can significantly influence the performances of functional near-infrared ... more ABSTRACT Probe geometry can significantly influence the performances of functional near-infrared spectroscopy applications. This in silico work presents a novel approach for probe placement optimization based on the minimization of sensitivity curvature.
Studies in health technology and informatics, 2013
This study shows task analysis results for the suturing task in the hybrid rigid scope Natural Or... more This study shows task analysis results for the suturing task in the hybrid rigid scope Natural Orifice Translumenal Endoscopic Surgery (NOTES) cholecystectomy procedure. A hierarchical task analysis tree was constructed from the video recordings of the NOTES procedure and time analysis for the suturing subtask was performed. Results indicate that the "Pull Suture Through" subtask requires the greatest time (25.4 sec) and the "Re-bite" subtask had the highest variation (6.6 sec). Intra-rater reliability test (k = 0.68) also showed consistency of the results obtained from the video motion analysis.
Studies in health technology and informatics, 2014
This study investigates the sensitivity of fiber placement positioning for the purpose of prefron... more This study investigates the sensitivity of fiber placement positioning for the purpose of prefrontal cortex imaging using functional near-infrared spectroscopy (fNIRS). Results indicate that our proposed optode placement has higher scaled-absorption sensitivity than the traditional International 10-20 system for optode placement based on Monte Carlo simulations.
A virtual reality-based simulator for natural orifice translumenal endoscopic surgery (NOTES) pro... more A virtual reality-based simulator for natural orifice translumenal endoscopic surgery (NOTES) procedures may be used for training and discovery of new tools and procedures. Our previous study (Sankaranarayanan et al. in Surg Endosc 27:1607-1616, 2013) shows that developing such a simulator for the transvaginal cholecystectomy procedure using a rigid endoscope will have the most impact on the field. However, prior to developing such a simulator, a thorough task analysis is necessary to determine the most important phases, tasks, and subtasks of this procedure. 19 rigid endoscope transvaginal hybrid NOTES cholecystectomy procedures and 11 traditional laparoscopic procedures have been recorded and de-identified prior to analysis. Hierarchical task analysis was conducted for the rigid endoscope transvaginal NOTES cholecystectomy. A time series analysis was conducted to evaluate the performance of the transvaginal NOTES and laparoscopic cholecystectomy procedures. Finally, a comparison of electrosurgery-based errors was performed by two independent qualified personnel. The most time-consuming tasks for both laparoscopic and NOTES cholecystectomy are removing areolar and connective tissue surrounding the gallbladder, exposing Calot's triangle, and dissecting the gallbladder off the liver bed with electrosurgery. There is a positive correlation of performance time between the removal of areolar and connective tissue and electrosurgery dissection tasks in NOTES (r = 0.415) and laparoscopic cholecystectomy (r = 0.684) with p < 0.10. During the electrosurgery task, the NOTES procedures had fewer errors related to lack of progress in gallbladder removal. Contrarily, laparoscopic procedures had fewer errors due to the instrument being out of the camera view. A thorough task analysis and video-based quantification of NOTES cholecystectomy has identified the most time-consuming tasks. A comparison of the surgical errors during electrosurgery gallbladder dissection establishes that the NOTES procedure, while still new, is not inferior to the established laparoscopic procedure.
Studies in health technology and informatics, 2013
Natural orifice translumenal endoscopic surgery (NOTES) is an experimental surgical technique wit... more Natural orifice translumenal endoscopic surgery (NOTES) is an experimental surgical technique with benefits including reduced pain, post operative recovery period and better cosmesis compared to traditional laparoscopic procedures. In a pure NOTES procedure, a flexible endoscope is used for performing the surgery and visualization. The Virtual Translumenal Endoscopic Surgical Trainer (VTEST(TM)) is being developed as a platform to train for NOTES procedures and innovate NOTES tools and techniques. In this work we report the design specification for the hardware interface to be used for VTEST(TM).
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Papers by Arun Nemani