I-STARs
         
Faculty and Staff
Jeffrey H. Siewerdsen, Ph.D.
Professor
Dept. of Biomedical Engineering
Dept. of Computer Science
Russell H. Morgan Dept. of Radiology
Armstrong Institute for Patient Safety and Quality
Johns Hopkins University
Traylor Building, Room 718
720 Rutland Avenue
Baltimore MD 21205

Phone: 443-287-6269
FAX: 410-955-1115
Email: jeff.siewerdsen@jhu.edu
  web J. Webster Stayman, Ph.D.
Research Assistant Professor
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1314
FAX: 410-955-1115
Email: web.stayman@jhu.edu
Dr. Jeff Siewerdsen founded the I-STAR Lab as a collaborative endeavor among technical disciplines (such as engineering and physics) and clinical disciplines, such as radiology, surgery, and radiation therapy. He is primary faculty in Biomedical Engineering and Principal Investigator on topics of image quality and cone-beam CT applications in diagnostic and image-guided procedures. He leads a program of interdisciplinary research spanning projects in medical imaging physics, diagnostic radiology, and image-guided interventions. His core interests include the physics of medical imaging, with a focus on advanced x-ray CT and spectral imaging modalities, the mathematics of image quality, the design of novel imaging systems for new applications, and 3D deformable image registration. Strong collaboration with experts in surgery, radiation therapy, and radiology guides and accelerates the translation of new technologies into early clinical application.

More information: Hopkins BME/~siewerdsen
 
Dr. Web Stayman is faculty in Biomedical Engineering and Principal Investigator on topics of advanced 3D image reconstruction with applications in diagnostic radiology, and image-guided interventions. With over 15 years of experience in tomography and other imaging applications, his expertise includes both emission tomography and transmission tomography (CT, tomosynthesis, and cone-beam CT). He leads research activities in advanced 3D reconstruction, including model-based statistical / iterative reconstruction, regularization methods, and modeling of imaging systems. He leads development of a generalized framework for penalized likelihood (PL) reconstruction combining statistical models of noise and image formation with incorporation of prior information, including patient-specific prior images, atlases, and models of components / devices known to be in the field of view. His research includes algorithm development and physical experimentation for imaging system design and optimization.
wz Wojciech Zbijewski, Ph.D.
Faculty Research Associate
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1305
Email: wzbijewski@jhu.edu
  adam Adam Wang, Ph.D.
Research Scientist
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1329 (I-STAR)
Email: adamwang AT jhu DOT edu
Dr. Wojtek Zbijewski is a physicist whose research interests include x-ray CT image reconstruction, Monte Carlo modeling, and the development and novel imaging systems. He leads activities in imaging system instrumentation throughout the I-STAR Lab, including cone-beam CT, photon counting CT, and and advanced volumetric imaging for extremities imaging in musculoskeletal radiology, orthopaedics, and rheumatology. He obtained his PhD from University of Utrecht, the Netherlands, under the supervision of Dr. F. Beekman. His background includes the development of statistical reconstruction algorithms for x-ray CT and scatter correction methods for cone-beam CT using accelerated Monte Carlo techniques. His experience includes industrial R&D, where his work involved the design of specialized cone-beam CT systems for image-guided surgery, ENT, and dental applications.
 
Dr. Wang is a research scientist with expertise in imaging physics and dual-energy CT. His research involves the development of novel 3D imaging techniques for image-guided surgery for improved image quality and reduced radiation dose. Methods for model-based reconstruction in cone-beam CT offer the capability to image with sparse projections at low dose and with reduced artifacts. Adam also works on the development of new dual-energy CT imaging techniques, including modeling of image quality, the development of low-noise decomposition / reconstruction methods, and application to new platforms for dual-energy and photon-counting CT.
yoshito Yoshito Otake, Ph.D.
Senior Research Scientist
Department of Biomedical Engineering
Department of Computer Science
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1309 (I-STAR)
Phone: 410-516-5396 (CSEB)
FAX: 410-516-4410 (CSEB)
Email: otake AT jhu DOT edu
  alex Alejandro Sisniega, Ph.D.
Research Scientist
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1329 (I-STAR)
Email: asisniega AT jhu DOT edu
Dr. Yoshito Otake is a research fellow in the Department of Computer Science at Johns Hopkins University and recipient of a JSPS Postdoctoral Fellowship for Research Abroad. His work includes the integration of novel surgical navigation and visualization systems for intraoprative guidance. He leads research and mentors students in the development of novel tracking systems, video augmentation techniques, GPU-accelerated (CUDA) algorithms for image registration and reconstruction, and streamlined integration with C-arm cone-beam CT within the TREK software architecture.
 
Dr. Sisniega is a postdoctoral research fellow in the Department of Biomedical Engineering at Johns Hopkins University and an expert in 3D imaging, models, and simulation. His research includes the development of high-performance Monte Carlo simulation methods for 3D imaging, including GPU implementations for high-fidelity, high-speed x-ray scatter simulation, dose calculation, and dual-energy imaging. His background includes the development of novel 3D imaging systems for preclinical imaging and integration of multiple imaging modalities, including molecular imaging and cone-beam CT.
grace Grace Jianan Gang
Graduate Research Assistant
Institute of Biomaterials and Biomedical Engineering (University of Toronto)
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1319
Email: grace.j.gang AT jhu.edu
  job POSITION OPEN!
Ph.D.
Research Scientist

Department of Biomedical Engineering
Johns Hopkins University
Grace Gang is a PhD student working on the development of mathematical models of image quality for advanced x-ray imaging systems. Her graduate work involves cascaded systems analysis of tomosynthesis and cone-beam CT - theoretical models combining 3D Fourier metrics (noise-equivalent quanta) with mathematical descriptions of anatomical background and imaging task. Her undergraduate work included deformable registration using mutual information in a dual-energy chest radiography. Her groundbreaking work: demonstrating agreement of theoretical models for 3D detectability with real observer preformance in tomosynthesis and cone-beam CT.
 
Full-time position as a Research Scientist in the Department of Biomedical Engineering at Johns Hopkins University. Utilize advanced scientific knowledge toward research in medical imaging and image-guided interventions. Develop, design, and manage substantial research projects, coordinate objectives and work alongside team members. Oversee data collection and analysis. Use advanced knowledge base to formulate research method and author/co-author publications, speak at conferences, assist with grant proposals, and independently develop experimental protocols. This is a full-time position with continuation and advancement contingent on performance and the availability of extramural grant funding.

Qualifications: PhD in physics, engineering, or related field with experience in medical imaging . Technical knowledge CT imaging, experimentation, and image reconstruction.

Contact Dr. Jeff Siewerdsen (jeff.siewerdsen@jhu.edu).edu for details.
         
Students
Hao Dang
Graduate Research Assistant
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1309
Email: hao.dang AT jhu.edu
  ali Ali Uneri
Graduate Research Assistant
Department of Computer Science
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1309
Email:ali.uneri@jhu.edu
Hao Dang is a PhD student in the Department of Biomedical Engineering at Johns Hopkins University and a research assistant in the I-STAR Lab. His research includes development of advanced 3D image reconstruction methods for image-guided interventions. His past research includes automatic image-world registration in surgical navigation, integrating C-Arm cone-beam CT with real-time tracking in seamless workflow. Other work includes intraoperative registration update methods for robotic skull drilling and novel similarity metrics and saliency-based hierarchy models for accurate 3D-3D image registration.
 
Ali Uneri in a PhD student in Computer Science at Hopkins and works on the development and integration of new surgical navigation tools for use in image-guided procedures. His thesis includes the the design and development of the TREK software architecture for intraoperative imaging and surgical guidance, combining open-source 3D Slicer and CISST libraries for surgical navigation based on intraoperative cone-beam CT. His core research includes the development of fast 3D-2D registration and high-quality 3D image reconstruction methods for surgical guidance. He also works on novel surgical tracker configurations, real-time thoracoscopic video augmentation, and methods for deformable image registration in thoracic surgery. His previous experience includes the development of surgical robotics for knee and hip replacement procedures.
sureerat Sureerat (Ja) Reaungamornrat
Graduate Research Assistant
Department of Computer Science
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1309
Email: sreaung1@jhu.edu
  steve Steven Tilley II
Graduate Research Assistant
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1309
Email:ali.stilley2@jhmi.edu
Sureerat ("Ja") Reaungamornrat is a Ph.D. student in the Department of Computer Science at John Hopkins University and a recipient of the Royal Thai Government Scholarship. Her current research involves the development of piecewise-rigid deformable image registration for image-guided spine surgery.  Her previous work at Hopkins included the development of the registration framework for cone-beam CT (CBCT)-guided transoral robotic surgery, integrating Gaussian mixture and Demons deformable registration. She received her M.Sc degree from the Department of Computer Science at John Hopkins University in 2011 on the topic of surgical guidance using CBCT. She received her B.Eng degree from King Monkut’s Institute of Technology, Bangkok, Thailand in 2007, and she worked as a research assistant at the Department of Biomedical Engineering, Mahidol University, Bangkok, Thailand in 2008, where her research included surgical navigation and autonomous rescue robots.
 
Steve Tilley is a PhD student Biomedical Engineering at Hopkins working on the development of novel 3D imaging systems.His research includes development of photon counting detectors for high-quality spectral CT and the development of novel 3D image reconstruction methods, including the Known-Component Reconstruction (KCR) method for model-based reconstruction. His previous experience in Biological Engineering at Cornel Unviersity includes work in 2-photon fluorescence microscopy and hyperspectral imaging using a 16-channel fluoroescence detector system.
jen Jennifer Xu
Graduate Research Assistant
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1309
Email: jennifexu AT gmail DOT com
  student Ph.D. Student
(position open)
 
Jen Xu is a PhD student in Biomedical Engineering at Hopkins. Her PhD project involves the development, characterization, and modeling of photon counting detectors and new methods for photon counting spectral (dual-energy) CT. She previously worked on the technical assessment of a new cone-beam CT scanning system for ENT and maxillofacial imaging undergoing trials at Johns Hopkins Hospital. Her work includes modeling and expermientation of single-energy and spectral cone-beam CT image quality on both the flat-panel CBCT Imaging Bench and photon counting CT bench, helping to standardize methods for characterization of the CBCT noise-power spectrum (NPS), noise-equivalent quanta (NEQ), and dosimetry for volumetric beams.
 
Project
Research in 3D image reconstruction and image-guided surgery suitable to a PhD project. Topics include the development and translation of high-quality cone-beam CT for surgical guidance, novel 3D image reconstruction techniques, and deformable image registration.

Contact Dr. Jeff Siewerdsen (jeff.siewerdsen@jhu.edu) for details.
         
I-STAR COLLABORATORS
john John Carrino, M.D.
Associate Professor
Departments of Radiology
and Orthopaedic Surgery
Johns Hopkins University
JHOC 5165
601 N. Caroline Street
Baltimore MD 21287

Phone: 443-287-6032 (admin)
Email: jcarrin2 AT jhmi DOT edu
  gary Gary Gallia, M.D.
Assistant Professor
Department of Neurosurgery
The Johns Hopkins Hospital
Phipps Bldg, Rm 118
600 N. Wolfe Street
Baltimore, MD 21287

Phone: 410-614-0585
Email: ggallia1 AT jhmi DOT edu
Dr. John Carrino is Section Chief of Musculoskeletal Radiology at Johns Hopkins University. He received his MD from Geoge Washington University and MPH from the Harvard School of Public Health. His core interests include spine imaging, novel MR imaging techniques, health services research, and radiology informatics. He is involved in a number of collaborative projects, notably in the field of musculoskeletal diagnostic imaging. He collaborates closely with the I-STAR Lab in the development of a dedicated cone-beam CT system for extremities imaging, a system for high-quality portable dual-energy imaging for the ICU, and in image quality analysis, ROC studies, and CT dosimetry.

More information: Hopkins Radiology/~carrino
 
Dr. Gary Gallia is an Assistant Professor of Neurosurgery and Oncology and the Director of Endoscopic and Minimally Invasive Neurosurgery at Johns Hopkins University, focusing on neurosurgical oncology. He utilizes state-of-the-art techniques for computer-assisted surgical navigation in minimally invasive and neuroendoscopic approaches in the management of patients with skull base tumors. He collaborates closely with the I-STAR Lab in the translation of high-performance C-arm cone-beam CT and surgical guidance systems from the laboratory to preclinical application in skull base surgery.

More information: Hopkins Neurosurgery/~gallia
greg Gregory Hager, Ph.D.
Professor and Chair
Dept. of Computer Science
Computational Sciences and Engineering Bldg, Room 12
Johns Hopkins University
3400 N. Charles St.
Baltimore, MD 21218-2686

Phone: (410) 516-5521
Fax: (410) 516-5553
  jay A. Jay Khanna, M.D.
Associate Professor
Dept. of Orthopaedic Surgery
Johns Hopkins University
Good Samaritan Hospital
5601 Loch Raven Blvd, Rm G-1
Baltimore, MD USA 21239

Phone: 443-444-4538
Email: akhanna1@jhmi.edu
Dr. Gregory Hager is Professor and Chair of the Department of Computer Science at Johns Hopkins University. His principal areas of research are computer vision and robotics, and his application interests are in the area of medical devices and human-machine systems. He directs the Computational Interaction and Robotics Lab (CIRL). He is also the Deputy Director of the NSF Engineering Research Center for Computer-Integrated Surgical Systems and Technology (ERC-CISST). He was elected a Fellow of the IEEE in 2006 for his contributions to computer vision and robotics. He collaborates with the I-STAR Lab in the development of high-precision video-CT registration for C-arm cone-beam CT-guided head and neck / skull base surgery.

More information: http://www.cs.jhu.edu/~hager
 
Dr. Jay Khanna is an Associate Professor of Orthopaedic Surgery and Biomedical Engineering at the Johns Hopkins University. He is a spine surgeon with felllowship training in both orthopaedic and neurologic spine surgery. His clinical practice includes all aspects of spine surgery although his clinical and research areas of interest lie in the sub-field of minimally invasive spine surgery. In addition to his clinical expertise and leadership in the field of spine surgery, he leads research and entrepreneurial partnerships throughout Johns Hopkins, including his role as Clinical Director of the CBID (Center for Bioengineering, Innovation and Design) Program. He works closely with the I-STAR Lab in the development of C-arm cone-beam CT for image-guided spine surgery, evaluation of surgical workflow, minimization of radiation dose, and translation to clinical application in orthopaedic surgeries.

More information: Hopkins Orthopaedic Surgery/~khanna
junghoon Junghoon Lee, Ph.D.
Associate Research Faculty
Department of Electrical and Computer Engineering
Johns Hopkins University
Traylor Building, Room 726
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-1305 (I-STAR)
Phone: 410-516-6820 (ECE)
Email: junghoon@jhu.edu
  mahesh Mahadevappa Mahesh, Ph.D.
Associate Professor
Chief Physicist
Department of Radiology
Johns Hopkins University
JHOC Suite 4235
601 N. Caroline Street
Baltimore, MD 21287-0856

Phone: 410-955-5115
Email: mmahesh@ jhmi.edu
Dr. Junghoon ('Daniel') Lee is faculty in the Department of Electrical and Computer Engineering (ECE) and the Engineering Research Center for Computer-Integrated Surgical Systems and Technology (ERC-CISST) at Hopkins. His interests include statistical signal/image processing and computer-assisted interventions. His work includes modeling of 3D image quality in tomosynthesis and cone-beam CT and the development of novel 3D image reconstruction techniques, particularly incorporating prior information (e.g., preoperative image and/or statistical atlas models) in 3D reconstruction from sparse and/or short-scan data. His background includes research in image-guided neurosurgery, virtual simulation in cardiac surgery, simultaneous 3-D reconstruction and classification of viruses in electron microscopy, ASIC design, and telemetry for the total artifical heart.
 
Dr. Mahadevappa Mahesh, MS, PhD, FAAPM, FACR, is Associate Professor of Radiology in the Division of Cardiology at the Johns Hopkins University School of Medicine. As Chief Physicist at the Johns Hopkins Hospital, he oversees the quality assurance program for Diagnostic Radiology, including compliance with state and federal regulations and ensuring safe use of radiation to patients. He is a recognized expert in the field of radiation dosimetry and regularly provides counsel to patients regarding radiation exposure concerns. His research interests include multiple-detector computed tomography (MDCT), interventional fluoroscopy, and digital mammography. He collaborates closely with the I-STAR Lab in the development of advanced 3D imaging systems, dual-energy radiography systems, novel imaging phantoms, and the minimization of radiation dose.

More information: Hopkins Radiology/~mahesh
jerry Jerry L. Prince, Ph.D.
Professor
Department of Electrical and Computer Engineering
201B Clark Hall
3400 North Charles St.
Baltimore MD 21218

Phone: 410-516-5192
Fax: 410-516-5566
Email: prince AT jhu DOT edu
  doug Douglas Reh, M.D.
Assistant Professor
Department of Otolaryngology - Head and Neck Surgery
Division of Rhinology and Sinus Surgery
Johns Hopkins University
JHOC, 6th Floor
601 N. Caroline Street
Baltimore MD 21287-0910

Phone: 410-955-2307
Email: dreh1 AT jhmi DOT edu
Dr. Jerry Prince joined the faculty at Johns Hopkins University in 1989, where he is the William B. Kouwenhoven Professor of Electrical and Computer Engineering. He holds joint appointments in the Departments of Radiology and Biomedical Engineering and a secondary appointment in Applied Mathematics and Statistics. He is also Associate Director for Research of the Engineering Research Center for Computer Integrated Surgical Systems and Technology (ERC-CISST). His research interests are in image processing and computer vision with application to medical imaging. He collaborates with the I-STAR Lab on image quality models, observer performance, image registration, and advanced reconstruction techniques.

More information: http://www.iacl.ece.jhu.edu/Prince
 
Dr. Doug Reh is a surgeon in the Department of Otolaryngology - Head and Neck Surgery at Johns Hopkins Hospital. His clinical expertise includes a broad spectrum of head and neck interventions, including: complex and revision endoscopic sinus surgery,endoscopic skull base surgery, management of chronic sinusitis with polyps, revision frontal sinus surgery, sinonasal and anterior skull base tumors, sinonasal cerebrospinal fluid leaks, and endoscopic management of nasolacrimal duct obstruction and Grave's orbitopathy. He collaborates with the I-STAR Lab closely in the development of C-arm cone-beam CT and video-CT registration for surgical guidance in head and neck / skull-base surgery.

More information: Hopkins Otolaryngology-HNS/~reh
jeremy Jeremy Richmon, M.D.
Assistant Professor
Department of Otolaryngology - Head and Neck Surgery
Johns Hopkins University

Phone: 410-955-6420
Email: jrichmo7 AT jhmi DOT edu
  ken Katsuyuki (Ken) Taguchi, Ph.D.
Associate Professor
Department of Radiology
Johns Hopkins University

Phone: 433-287-2974
Email: ktaguchi AT jhmi DOT edu
Dr. Jeremy Richmon is head and neck surgeon and expert in robotic-assisted surgery. He has helped to pioneer new approaches in minimally invasive, robotic-assisted thyroidectomy and base of tongue surgery. His clinical expertise includes head and neck cancer, microsvascular reconstruction, and tumors of the oral cavity, salivary glands, pharynx, larynx, sinuses, and skull base. Collaboration with I-STAR includes the development of advanced image-guidance and image registration techniques for integration in trans-oral robotic-assisted surgery.

More information: Hopkins Otolaryngology-HNS
 
Dr. Ken Taguchi is recognized leader in the field of CT image science, 3D / 4D image reconstruction, CT data acquisition, photon counting, and spectral CT. He is among the pioneers of multi-detector CT (MDCT) in the 1990s and leads a vibrant program of research in advanced CT imaging technologies. Dr. Taguchi's collaboration with I-STAR includes the development of new photon counting detector systems for CT and spectral CT, including the development of new experimental systems for photon counting CT and new algorithms for high-quality dual-energy CT decomposition.

More information: Division of Medical Imaging Physics (DMIP)
russ Russell H. Taylor, Ph.D.
Professor
Dept. of Computer Science
127 Computational Sciences and Engineering Building
Johns Hopkins University
3400 North Charles Street
Baltimore, Maryland 21218 USA

Phone: 410-516-6299
Email: rht AT jhu DOT edu
  Gaurav Thawait, M.D.
Research Fellow
Department of Radiology
Johns Hopkins University

Phone: 443-287-6032
Email: gthawai1 AT jhmi DOT edu
Dr. Russ Taylor is the Director of the NSF Engineering Research Center for Computer-Integrated Surgical Systems and Technology (ERC-CISST). His work focuses on robotics in medicine, image-guided interventions, medical imaging and modeling, and integration of advanced interventional systems. The theme underlying a broad spectrum of research in his laboratories is the basic insight that information-based technologies can have similar impact in computer-integrated medicine as they have had on computer-integrated manufacturing techniques. He collaborates closely with the I-STAR Lab on topics of image-guided interventions and advanced image reconstruction and modeling techniques.

More information: http://www.cs.jhu.edu/~rht/
 
Dr. Gaurav Kumar Thawait, M.D. is a Research Fellow in the Department of Radiology at the Johns Hopkins Medical Institution. His key interests are in Musculoskeletal Radiology, with emphasis on advanced functional imaging applications, dual-energy CT, minimization of radiation dose and MR neurography. He collaborates with the I-STAR Lab in the development of a dedicated extremity musculoskeletal CBCT scanner, advanced dual-energy CBCT imaging techniques, as well as novel 3D and 4D imaging phantoms.
         
Research Administration
tom Tom Judy
Senior Research Service Analyst
Department of Biomedical Engineering
Johns Hopkins University
Traylor Building, Room 606
720 Rutland Avenue
Baltimore MD 21205

Phone: 410-955-3277
FAX: 410-955-9826
Email: tom.judy@jhu.edu
Tom Judy is a research administrator for the Department of Biomedical Engineering and primary point of contact for the I-STAR Lab on matters pertaining to budget, purchasing, and general administration. An administrator and research manager by day, Tom is also the Captain of the Baltimore Ravens cheerleaders stunt team! Go Ravens!
I-STAR HOME
The I-STAR Laboratory
Department of Biomedical Engineering | Johns Hopkins University
Traylor Building, Room 726 | 720 Rutland Avenue | Baltimore, MD 21205