Dr. Hossein Mohamadipanah joined Stanford in March 2018 and his work focuses on data analysis and machine leaning in surgical education.
Current Role at Stanford
Education & Certifications
Postdoctoral, University of Wisconsin Madison, Data Analysis and Machine Learning (2017)
Postdoctoral, Oklahoma State Univesity, Machine Leaning (2015)
PhD in Mechanical Engineering, Oklahoma State University, Medical Robotics, Machine Learning, and Computer Vision (2014)
MSc in Mechanical Engineering, Sharif University of Technology, Robotics (2010)
Robotics, Machine Learning, Computer Vision, Manipulator Design.
Instructor, Oklahoma State University (June 1, 2015 - July 31, 2015)
Measurements and Instrumentation (MAE 3113)
Dynamic Visual Feedback During Junctional Tourniquet Training.
The Journal of surgical research
2019; 233: 444–52
BACKGROUND: This project involved the development and evaluation of a new visual bleeding feedback (VBF) system for tourniquet training. We hypothesized that dynamic VBF during junctional tourniquet training would be helpful and well received by trainees.MATERIALS AND METHODS: We designed the VBF to simulate femoral bleeding. Medical students (n=15) and emergency medical service (EMS) members (n=4) were randomized in a single-blind, crossover study to the VBF or without feedback groups. Poststudy surveys assessing VBF usefulness and recommendations were conducted along with participants' reported confidence using a 7-point Likert scale. Data from the different groups were compared using Wilcoxon signed-rank and rank-sum tests.RESULTS: Participants rated the helpfulness of the VBF highly (6.53/7.00) and indicated they were very likely to recommend the VBF simulator to others (6.80/7.00). Pre- and post-VBF confidence were not statistically different (P=0.59). Likewise, tourniquet application times for VBF and without feedback before crossover were not statistically different (P=0.63). Although participant confidence did not change significantly from beginning to end of the study (P=0.46), application time was significantly reduced (P=0.001).CONCLUSIONS: New tourniquet learners liked our VBF prototype and found it useful. Although confidence did not change over the course of the study for any group, application times improved. Future studies using outcomes of this study will allow us to continue VBF development as well as incorporate other quantitative measures of task performance to elucidate VBF's true benefit and help trainees achieve mastery in junctional tourniquet skills.
View details for PubMedID 30502284
Combining metrics from clinical simulators and sensorimotor tasks can reveal the training background of surgeons.
IEEE transactions on bio-medical engineering
Skill assessment in surgery traditionally has relied on expert observation and qualitative scoring. Our novel study design demonstrates how analysis of performance in sensorimotor tasks and bench-top surgical simulators can provide inferences about the technical proficiency as well as the training history of surgeons.Our unique study design examined metrics for basic sensorimotor tasks in a virtual reality interface as well as motion metrics in clinical scenario simulations. As indicators of training level, we considered survey responses from surgery residents, including the number of years post-graduation (PGY, four levels), research years (RY, three levels), and clinical years (CY, three levels). Next, we performed a linear discriminant analysis with cross-validation (90% training, 10% testing) to relate the training levels to the selected metrics.Using combined metrics from all stations, we found greater than chance predictions for each survey category, with an overall accuracy of 43.4±2.9% for identifying the level for post-graduate years, 79.1±1.0% accuracy for research training years, and 64.2±1.0% for clinical training years. Our main finding was that combining metrics from all stations resulted in more accurate predictions than using only sensorimotor or clinical scenario tasks. In addition, our analysis indicates that metrics related to the ability to cope with changes in the task environment were the most important predictors of training level.These results suggest that each simulator type provided crucial information for evaluating surgical proficiency. The methods developed in this study could improve evaluations of a surgeon's clinical proficiency as well as training potential in terms of basic sensorimotor ability.
View details for DOI 10.1109/TBME.2019.2892342
View details for PubMedID 30629489
Shortcut assessment: Can residents' operative performance be determined in the first five minutes of an operative task?
2018; 163 (6): 1207–12
BACKGROUND: The aim was to validate the potential use of a single, early procedure, operative task as a predictive metric for overall performance. The authors hypothesized that a shortcut psychomotor assessment would be as informative as a total procedural psychomotor assessment when evaluating laparoscopic ventral hernia repair performance on a simulator.METHODS: Using electromagnetic sensors, hand motion data were collected from 38 surgery residents during a simulated laparoscopic ventral hernia repair procedure. Three time-based phases of the procedure were defined: Early Phase (start time through completion of first anchoring suture), Mid Phase (start time through completion of second anchoring suture), and Total Operative Time. Correlations were calculated comparing time and motion metrics for each phase with the final laparoscopic ventral hernia repair score.RESULTS: Analyses revealed that execution time and motion, for the first anchoring suture, predicted procedural outcomes. Greater execution times and path lengths correlated to lesser laparoscopic ventral hernia repair scores (r = -0.56, P = .0008 and r = -0.51, P = .0025, respectively). Greater bimanual dexterity measures correlated to Greater LVH repair scores (r = + 0.47, P = .0058).CONCLUSIONS: This study provides validity evidence for use of a single, early operative task as a shortcut assessment to predict resident performance during a simulated laparoscopic ventral hernia repair procedure. With the continued development and decreasing costs of motion technology, faculty should be well-versed in the use of motion metrics for performance measurements. The results strongly support the use of dexterity and economy of motion (path length + execution time) metrics as early predictors of operative performance.
View details for PubMedID 29728259
- Residents' response to bleeding during a simulated robotic surgery task JOURNAL OF SURGICAL RESEARCH 2017; 220: 385–90
Residents' surgical performance during the laboratory years: an analysis of rule-based errors
JOURNAL OF SURGICAL RESEARCH
2017; 219: 226–31
Nearly one-third of surgical residents will enter into academic development during their surgical residency by dedicating time to a research fellowship for 1-3 y. Major interest lies in understanding how laboratory residents' surgical skills are affected by minimal clinical exposure during academic development. A widely held concern is that the time away from clinical exposure results in surgical skills decay. This study examines the impact of the academic development years on residents' operative performance. We hypothesize that the use of repeated, annual assessments may result in learning even without individual feedback on participants simulated performance.Surgical performance data were collected from laboratory residents (postgraduate years 2-5) during the summers of 2014, 2015, and 2016. Residents had 15 min to complete a shortened, simulated laparoscopic ventral hernia repair procedure. Final hernia repair skins from all participants were scored using a previously validated checklist. An analysis of variance test compared the mean performance scores of repeat participants to those of first time participants.Twenty-seven (37% female) laboratory residents provided 2-year assessment data over the 3-year span of the study. Second time performance revealed improvement from a mean score of 14 (standard error = 1.0) in the first year to 17.2 (SD = 0.9) in the second year, (F[1, 52] = 5.6, P = 0.022). Detailed analysis demonstrated improvement in performance for 3 grading criteria that were considered to be rule-based errors. There was no improvement in operative strategy errors.Analysis of longitudinal performance of laboratory residents shows higher scores for repeat participants in the category of rule-based errors. These findings suggest that laboratory residents can learn from rule-based mistakes when provided with annual performance-based assessments. This benefit was not seen with operative strategy errors and has important implications for using assessments not only for performance analysis but also as a learning experience.
View details for DOI 10.1016/j.jss.2017.05.129
View details for Web of Science ID 000413775200034
View details for PubMedID 29078886
- Robust Automatic Feature Tracking on Beating Human Hearts for Minimally Invasive CABG Surgery JOURNAL OF MEDICAL DEVICES-TRANSACTIONS OF THE ASME 2016; 10 (4)
Can a virtual reality assessment of fine motor skill predict successful central line insertion?
AMERICAN JOURNAL OF SURGERY
2016; 212 (4): 573-+
Due to the increased use of peripherally inserted central catheter lines, central lines are not performed as frequently. The aim of this study is to evaluate whether a virtual reality (VR)-based assessment of fine motor skills can be used as a valid and objective assessment of central line skills.Surgical residents (N = 43) from 7 general surgery programs performed a subclavian central line in a simulated setting. Then, they participated in a force discrimination task in a VR environment. Hand movements from the subclavian central line simulation were tracked by electromagnetic sensors. Gross movements as monitored by the electromagnetic sensors were compared with the fine motor metrics calculated from the force discrimination tasks in the VR environment.Long periods of inactivity (idle time) during needle insertion and lack of smooth movements, as detected by the electromagnetic sensors, showed a significant correlation with poor force discrimination in the VR environment. Also, long periods of needle insertion time correlated to the poor performance in force discrimination in the VR environment.This study shows that force discrimination in a defined VR environment correlates to needle insertion time, idle time, and hand smoothness when performing subclavian central line placement. Fine motor force discrimination may serve as a valid and objective assessment of the skills required for successful needle insertion when placing central lines.
View details for DOI 10.1016/j.amjsurg.2016.06.023
View details for Web of Science ID 000385925900003
View details for PubMedID 27649977
Predictive Model Reference Adaptive Controller to Compensate Heart Motion in Minimally Invasive CABG Surgery
CARDIOVASCULAR ENGINEERING AND TECHNOLOGY
2015; 6 (3): 329–39
Heart beating is a major challenge in minimally invasive coronary artery surgery. A promising solution is to develop a motion compensation robotic system that gives the surgeon an impression of operating on motionless tissue by synchronizing the surgical tool automatically with the heart tissue motion. To achieve higher control accuracy, an intelligent controller called Predictive Model Reference Adaptive Controller is presented herein, which is adapted not only by observed reference signals but, also by unknown reference signals that are not observed by a camera but could be predicted by a state space estimator. To develop such a system, first the heart surface motion is tracked by the Lucas-Kanade tracking algorithm and validated by human observation. The results of implementing this control algorithm on a real human heart data set show capability of achieving a motion compensation system with high control accuracy.
View details for DOI 10.1007/s13239-015-0225-y
View details for Web of Science ID 000380356800011
View details for PubMedID 26577364
- Effects of texture addition on optical flow performance in images with poor texture IMAGE AND VISION COMPUTING 2015; 40: 1–15