Sakti Srivastava

All Publications

• Collaborative Networked Virtual Surgical Simulators (CNVSS) Implementing Hybrid Client-Server Architecture: Factors Affecting Collaborative Performance PRESENCE-TELEOPERATORS AND VIRTUAL ENVIRONMENTS Diaz, C., Trefftz, H., Quintero, L., Acosta, D. A., Srivastava, S. 2015; 23 (4): 393-409

  View details for DOI 10.1162/PRES_a_00208

  View details for Web of Science ID 000351287300006

• Collaborative Networked Virtual Surgical Simulators (CNVSS): Factors Affecting Collaborative Performance PRESENCE-TELEOPERATORS AND VIRTUAL ENVIRONMENTS Diaz, C., Trefftz, H., Quintero, L., Acosta, D. A., Srivastava, S. 2013; 22 (1): 54-66

  View details for DOI 10.1162/PRES_a_00133

  View details for Web of Science ID 000318352600004

• Design, Development, and Evaluation of an Online Virtual Emergency Department for Training Trauma Teams SIMULATION IN HEALTHCARE Youngblood, P., Harter, P. M., Srivastava, S., Moffett, S., Heinrichs, W. L., Dev, P. 2008; 3 (3): 146-153

  Abstract

  Training interdisciplinary trauma teams to work effectively together using simulation technology has led to a reduction in medical errors in emergency department, operating room, and delivery room contexts. High-fidelity patient simulators (PSs)-the predominant method for training healthcare teams-are expensive to develop and implement and require that trainees be present in the same place at the same time. In contrast, online computer-based simulators are more cost effective and allow simultaneous participation by students in different locations and time zones. In this pilot study, the researchers created an online virtual emergency department (Virtual ED) for team training in crisis management, and compared the effectiveness of the Virtual ED with the PS. We hypothesized that there would be no difference in learning outcomes for graduating medical students trained with each method.In this pilot study, we used a pretest-posttest control group, experimental design in which 30 subjects were randomly assigned to either the Virtual ED or the PS system. In the Virtual ED each subject logged into the online environment and took the role of a team member. Four-person teams worked together in the Virtual ED, communicating in real time with live voice over Internet protocol, to manage computer-controlled patients who exhibited signs and symptoms of physical trauma. Each subject had the opportunity to be the team leader. The subjects' leadership behavior as demonstrated in both a pretest case and a posttest case was assessed by 3 raters, using a behaviorally anchored scale. In the PS environment, 4-person teams followed the same research protocol, using the same clinical scenarios in a Simulation Center. Guided by the Emergency Medicine Crisis Resource Management curriculum, both the Virtual ED and the PS groups applied the basic principles of team leadership and trauma management (Advanced Trauma Life Support) to manage 6 trauma cases-a pretest case, 4 training cases, and a posttest case. The subjects in each group were assessed individually with the same simulation method that they used for the training cases.Subjects who used either the Virtual ED or the PS showed significant improvement in performance between pretest and posttest cases (P < 0.05). In addition, there was no significant difference in subjects' performance between the 2 types of simulation, suggesting that the online Virtual ED may be as effective for learning team skills as the PS, the method widely used in Simulation Centers. Data on usability and attitudes toward both simulation methods as learning tools were equally positive.This study shows the potential value of using virtual learning environments for developing medical students' and resident physicians' team leadership and crisis management skills.

  View details for DOI 10.1097/SIH.0b013e31817bedf7

  View details for Web of Science ID 000207536200004

  View details for PubMedID 19088658

• Virtual Worlds for Teaching the New CPR to High School Students 15th Conference on Medicine Meets Virtual Reality Youngblood, P., Hedman, L., Creutzfeld, J., Fellander-Tsai, L., Stengard, K., Hansen, K., Dev, P., Srivastava, S., Kusumoto, L., Hendrick, A., Heinrichs, W. L. I O S PRESS. 2007: 515–519

  Abstract

  In this study we created a virtual 3D world for learning to manage medical emergencies and evaluated it with 24 high school students in the USA and Sweden. We found that students in both groups felt immersed and found the online simulation easy to use. Scores for flow and self-assessed flow were significantly higher for the RHS group as compared to the HG group (p=.001 and .023 respectively; Mann Whitney U test). Self-efficacy scores for the HG group were significantly higher after training (p=.016 Mann Whitney U test). Males in the RHS group scored significantly higher on flow and self assessed flow than females (p=.006 and p=.023 respectively; Mann Whitney U test). This study demonstrates the potential value of using MMOS for learning to respond to medical emergencies.

  View details for Web of Science ID 000270613800119

  View details for PubMedID 17377340

• Collaborative learning using Internet2 and remote collections of stereo dissection images CLINICAL ANATOMY Dev, P., Srivastava, S., Senger, S. 2006; 19 (3): 275-283

  Abstract

  We have investigated collaborative learning of anatomy over Internet2, using an application called remote stereo viewer (RSV). This application offers a unique method of teaching anatomy, using high-resolution stereoscopic images, in a client-server architecture. Rotated sequences of stereo image pairs were produced by volumetric rendering of the Visible female and by dissecting and photographing a cadaveric hand. A client-server application (RSV) was created to provide access to these image sets, using a highly interactive interface. The RSV system was used to provide a "virtual anatomy" session for students in the Stanford Medical School Gross Anatomy course. The RSV application allows both independent and collaborative modes of viewing. The most appealing aspects of the RSV application were the capacity for stereoscopic viewing and the potential to access the content remotely within a flexible temporal framework. The RSV technology, used over Internet2, thus serves as an effective complement to traditional methods of teaching gross anatomy.

  View details for DOI 10.1002/ca.20313

  View details for Web of Science ID 000237004100011

  View details for PubMedID 16506216

• The effect of arthroscopic sectioning of the lateral ligament complex of the elbow on posterolateral rotatory stability JOURNAL OF SHOULDER AND ELBOW SURGERY McAdams, T. R., Masters, G. W., Srivastava, S. 2005; 14 (3): 298-301

  Abstract

  This study evaluates the relative roles of the radial collateral ligament, the lateral ulnar collateral ligament, and the overlying musculature in posterolateral rotatory instability of the elbow. Fourteen cadaveric upper limbs underwent sequential arthroscopic sectioning of the lateral collateral ligament complex. After sectioning, arthroscopic and fluoroscopic evaluation of a lateral pivot shift test was done. Minimal instability was noted after the first section, but no difference between radial collateral or lateral ulnar collateral ligament sectioning was found. A greater degree of instability was seen between the first and second cut ( P = .0001), but no significant difference was seen between sectioning the 2 groups ( P = .61). Complete instability occurred only after sectioning the overlying musculature. On the basis of this study, injury to both the radial collateral and lateral ulnar collateral ligaments is necessary to cause significant posterolateral rotatory instability of the elbow. Furthermore, the overlying musculature plays an important role in overall stability.

  View details for DOI 10.1016/j.jse.2004.08.003

  View details for Web of Science ID 000229244200011

  View details for PubMedID 15889029

• Comparison of training on two laparoscopic simulators and assessment of skills transfer to surgical performance JOURNAL OF THE AMERICAN COLLEGE OF SURGEONS Youngblood, P. L., Srivastava, S., Curet, M., Heinrichs, W. L., Dev, P., Wren, S. M. 2005; 200 (4): 546-551

  Abstract

  Several studies have investigated the transfer of surgical trainees' skills acquired on surgical simulators to the operating room setting. The purpose of this study was to compare the effectiveness of two laparoscopic surgery simulators by assessing the transfer of skills learned on simulators to closely matched surgical tasks in the animal laboratory.In this post-test-only Control group study design, 46 surgically naive medical student volunteers were randomly assigned to one of three groups: Tower Trainer group (n = 16), LapSim group (n = 17), and Control group (n = 13). Outcomes measures included both time and accuracy scores on three laparoscopic tasks (Task 1: Grasp and Place; Task 2: Run the Bowel; Task 3: Clip and Cut) performed on live anesthetized pigs, and a global rating of overall performance as judged by four experienced surgeons.The Tower Trainer group performed significantly better than the Control group on 1 of 7 outcomes measures-Task 3: Time (p < 0.032), although the LapSim group performed significantly better than the Control group on 2 of 7 measures-Task 3: Time (p < 0.008) and Global score (p < 0.005). In comparing the two simulators, the LapSim group performed significantly better than the Tower Trainer group on 3 of 7 outcomes measures-Task 2: Time (p < 0.032), Task 2: Accuracy (p < 0.030) and Global score (p < 0.005), although the Tower Trainer group did not perform significantly better than the LapSim group on any measure.This study demonstrated that naive subjects trained on a virtual-reality part-task trainer performed better on live surgical tasks in a porcine model as compared with those trained with a traditional box trainer. These findings could aid in selection of appropriate training methodologies.

  View details for DOI 10.1016/j.jamcollsurg.2004.11.011

  View details for Web of Science ID 000228085200007

  View details for PubMedID 15804468

• The fundamental manipulations of surgery: A structural vocabulary for designing surgical curricula and simulators JOURNAL OF THE AMERICAN ASSOCIATION OF GYNECOLOGIC LAPAROSCOPISTS Heinrichs, W. L., Srivastava, S., Montgomery, K., Dev, P. 2004; 11 (4): 450-456

  Abstract

  A structured vocabulary is proposed for supporting the design and development of advanced surgical simulators. Nine fundamental surgical instrument-tissue actions or manipulations are defined and common synonyms provided. The vocabulary focuses on "target skills" that are familiar to surgeons, in comparison with "enabling skills" from the lexicon of instructional designers and psychometricians. The adoption of this vocabulary can facilitate communication among surgeons and bioengineers developing "high-fidelity" surgical simulators.

  View details for Web of Science ID 000225326500004

  View details for PubMedID 15701184

• LUCY: A 3-D pelvic model for surgical simulation JOURNAL OF THE AMERICAN ASSOCIATION OF GYNECOLOGIC LAPAROSCOPISTS Heinrichs, W. L., Srivastava, S., Dev, P., Chase, R. A. 2004; 11 (3): 326-331

  Abstract

  Development of 3-D models of human anatomy for use in virtual reality simulators is anticipated to enhance surgical training. These models may be a valuable resource for gaining mastery of minimal-access procedures. The pelvis portion (hip to upper-thigh) of a 32-year-old female cadaver was frozen and sectioned axially in approximately 2-mm increments as the first step in producing an accurately representative 3-D model of the human female pelvis. Photographic exposures of the entire series of 95 sections were then converted to digital format. Adobe PhotoShop masks for each structure were created and converted into wire-frame and surface-textured models; this aggregate model set was named "LUCY." To date, 3-D representations of 40 pelvic structures (over 2200 individual masks) have been modeled In conjunction with haptic technology, these virtual anatomic models will enable users to practice fundamental surgical manipulations and procedures such as tubal ligation and ovariectomy. The deployment of surgical-simulation models such as LUCY may facilitate technical-performance aspects of surgical training, particularly those associated with minimal-access procedures. Manipulations and procedures can be practiced over the Internet, providing a host of flexible options to enhance the surgical curricula.

  View details for Web of Science ID 000223752600008

  View details for PubMedID 15559342

• Evaluation of a surgical simulator for learning clinical anatomy MEDICAL EDUCATION Hariri, S., Rawn, C., Srivastava, S., Youngblood, P., Ladd, A. 2004; 38 (8): 896-902

  Abstract

  New techniques in imaging and surgery have made 3-dimensional anatomical knowledge an increasingly important goal of medical education. This study compared the efficacy of 2 supplemental, self-study methods for learning shoulder joint anatomy to determine which method provides for greater transfer of learning to the clinical setting.Two groups of medical students studied shoulder joint anatomy using either a second-generation virtual reality surgical simulator or images from a textbook. They were then asked to identify anatomical structures of the shoulder joint as they appeared in a videotape of a live arthroscopic procedure.The mean identification scores, out of a possible score of 7, were 3.1 +/- 1.3 for the simulator group and 2.9 +/- 1.5 for the textbook group (P = 0.70). Student ratings of the 2 methods on a 5-point Likert scale were significantly different. The simulator group rated the simulator more highly as an effective learning tool than the textbook group rated the textbook (means of 3.2 +/- 0.7 and 2.6 +/- 0.5, respectively, P = 0.02). Furthermore, the simulator group indicated that they were more likely to use the simulator as a learning tool if it were available to them than the textbook group was willing to use the textbook (means of 4.0 +/- 1.2 and 3.0 +/- 0.9, respectively, P = 0.02).Our results show that this surgical simulator is at least as effective as textbook images for learning anatomy and could enhance student learning through increased motivation. These findings provide insight into simulator development and strategies for learning anatomy. Possible explanations and future research directions are discussed.

  View details for DOI 10.1111/j.1365-2929.2004.01897.x

  View details for Web of Science ID 000223249000017

  View details for PubMedID 15271051

• Initial evaluation of a shoulder arthroscopy simulator: Establishing construct validity JOURNAL OF SHOULDER AND ELBOW SURGERY Srivastava, S., Youngblood, P. L., Rawn, C., Hariri, S., Heinrichs, W. L., Ladd, A. L. 2004; 13 (2): 196-205

  Abstract

  Formal evaluation of surgical simulators is essential before their introduction into training programs. We report our assessment of the Mentice Corp Procedicus shoulder arthroscopy simulator. This study tests the hypothesis of construct validity that experienced surgeons will score better on the simulator than individuals with minimal to no experience with the technique. Thirty-five subjects were stratified into three groups (novice, intermediate, and expert) based on their past 5 years' experience with shoulder arthroscopies. Each subject had an identical session on the simulator and completed anatomic identification, hook manipulations, and scope navigation exercises. We found statistically significant differences among the three groups in hook manipulation and scope navigation exercises, with the expert group performing the exercises more quickly (P =.013) and more accurately (P =.002) than the other two groups. No statistically significant differences were found among the groups in the identification of anatomic landmarks. Experts rated the simulator as an effective teaching tool, giving it a mean score of 4.22 and 4.44 (maximum, 5) for teaching instrument control and triangulation, respectively.

  View details for DOI 10.1016/j.jse.2003.12.009

  View details for Web of Science ID 000220272700014

  View details for PubMedID 14997099

• Arthroscopic evaluation of scaphoid waist fracture stability and the role of the radioscaphocapitate ligament ARTHROSCOPY-THE JOURNAL OF ARTHROSCOPIC AND RELATED SURGERY McAdams, T. R., Srivastava, S. 2004; 20 (2): 152-157

  Abstract

  The purpose of this article is to arthroscopically evaluate the effect of forearm rotation on scaphoid fracture displacement and the impact of intra-articular ligament sectioning.Controlled laboratory study.Scaphoid fracture stability is studied arthroscopically in 10 cadaveric upper limbs. Displacement of the osteotomized scaphoid with and without forearm rotation is arthroscopically evaluated before and after radioscaphocapitate (RSC) ligament sectioning.No rotation at the fracture site was identified in full pronation and full supination with the wrist immobilized. With the RSC ligament intact, no immobilization, and the wrist fully pronated, 25% of scaphoid fractures rotated less than 1 mm, 62.5% rotated 1 to 2 mm, and 12.5% rotated more than 2 mm. After sectioning the RSC ligament, the fully pronated wrist resulted in rotation of less than 1 mm in 75% and 1 to 2 mm in 25%. No rotation at the fracture site was seen with supination, with or without immobilization. No difference was found between loaded and unloaded trials.Based on this observational data, it appears safe to use a below-elbow thumb spica cast in the treatment of minimally displaced scaphoid waist fractures. Sectioning of the RSC ligament resulted in reduced amount of rotation at the scaphoid waist fracture; thus the RSC ligament may be a deforming force rather than a stabilizing force in scaphoid waist fractures. Arthroscopy may be a valuable tool in the study of the effect of ligament sectioning on fracture stability.

  View details for DOI 10.1016/j.arthro.2003.11.023

  View details for Web of Science ID 000220090600006

  View details for PubMedID 14760347

• Educational tools in support of the Stanford MediaServer Joint Conference on Digital Libraries Stevenson, D., Chao, C. C., Srivastava, S., Durack, J. C., Ladd, A., Montgomery, K., Dev, P. IEEE COMPUTER SOC. 2003: 377–377

  View details for Web of Science ID 000183728000055

• Simulated medical learning environments on the Internet JOURNAL OF THE AMERICAN MEDICAL INFORMATICS ASSOCIATION Dev, P., Montgomery, K., Senger, S., Heinrichs, W. L., Srivastava, S., Waldron, K. 2002; 9 (5): 437-447

  Abstract

  Learning anatomy and surgical procedures requires both a conceptual understanding of three-dimensional anatomy and a hands-on manipulation of tools and tissue. Such virtual resources are not available widely, are expensive, and may be culturally disallowed. Simulation technology, using high-performance computers and graphics, permits realistic real-time display of anatomy. Haptics technology supports the ability to probe and feel this virtual anatomy through the use of virtual tools. The Internet permits world-wide access to resources. We have brought together high-performance servers and high-bandwidth communication using the Next Generation Internet and complex bimanual haptics to simulate a tool-based learning environment for wide use. This article presents the technologic basis of this environment and some evaluation of its use in the gross anatomy course at Stanford University.

  View details for DOI 10.1197/jamia.M1089

  View details for Web of Science ID 000178205000002

  View details for PubMedID 12223496

  View details for PubMedCentralID PMC346631

• Visual representations of physical abilities: Reverse haptic technology? 10th Annual Medicine Meets Virtual Reality Conference Pugh, C. M., Srivastava, S., Heinrichs, M. L. I O S PRESS. 2002: 380–381

  View details for Web of Science ID 000176591900068

  View details for PubMedID 15458118

• Interactive simulation of the human hand 16th International Congress and Exhibition on Computer Assisted Radiology and Surgery Sibille, L., Teschner, M., Srivastava, S., Latombe, J. C. SPRINGER-VERLAG BERLIN. 2002: 7–12

  View details for Web of Science ID 000178013900002

• Simulated learning environments in anatomy and surgery delivered via the Next Generation Internet 10th World Congress on Medical Informatics (MEDINFO 2001) Dev, P., Heinrichs, W. L., Srivastava, S., Montgomery, K. N., Senger, S., Temkin, B., Hasser, C., Latombe, J. C., HEEGAARD, J., Youngblood, P., Friedman, C. P., Waldron, K. I O S PRESS. 2001: 1014–1018

  Abstract

  The Next Generation Internet (NGI) will provide high bandwidth, guaranteed Quality of Service, collaboration and security, features that are not available in today's Internet. Applications that take advantage of these features will need to build them into their pedagogic requirements. We present the Anatomy Workbench and the Surgery Workbench, two applications that require most of these features of the NGI. We used pedagogic need and NGI features to define a set of applications that would be difficult to operate on the current Internet, and that would require the features of the NGI. These applications require rich graphics and visualization, and extensive haptic interaction with biomechanical models that represent bony and soft tissue. We are in the process of implementing these applications, and some examples are presented here. An additional feature that we required was that the applications be scalable such that they could run on either on a low-end desktop device with minimal manipulation tools or on a fully outfitted high-end graphic computer with a realistic set of surgical tools. The Anatomy and Surgery Workbenches will be used to test the features of the NGI, and to show the importance of these new features for innovative educational applications.

  View details for Web of Science ID 000172901700272

  View details for PubMedID 11604884

• The effect of simulator use on learning and self-assessment: The case of Stanford University's E-Pelvis simulator Conference on Medicine Meets Virtual Reality 2001 Pugh, C. M., Srivastava, S., SHAVELSON, R., Walker, D., Cotner, T., Scarloss, B., Kuo, M., Rawn, C., Dev, P., Krummel, T. H., Heinrichs, L. H. I O S PRESS. 2001: 396–400

  View details for Web of Science ID 000169103300074

  View details for PubMedID 11317776

• Visual language to interface users of educational surgical simulators for fundamental surgical manipulations 14th International Congress and Exhibition on Computer Assisted Radiology and Surgery (CARS 2000) Heinrichs, W. L., Srivastava, S., Pugh, C., Rakhlin, L., Montgomery, K., PICHUMANI, R., Rao, S., Dev, P. ELSEVIER SCIENCE BV. 2000: 29–34

  View details for Web of Science ID 000165685600005