• A multimodal image guiding system for Navigated Ultrasound Bronchoscopy (EBUS): A human feasibility study 

      Sorger, Hanne; Hofstad, Erlend Fagertun; Amundsen, Tore; Langø, Thomas; Bakeng, Janne Beate Lervik; Leira, Håkon Olav (Journal article; Peer reviewed, 2017)
      Background Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) is the endoscopic method of choice for confirming lung cancer metastasis to mediastinal lymph nodes. Precision is crucial for correct staging ...
    • Accuracy of electromagnetic tracking with a prototype field generator in an interventional OR setting 

      Bø, Lars Eirik; Leira, Håkon Olav; Tangen, Geir Arne; Hofstad, Erlend Fagertun; Amundsen, Tore; Langø, Thomas (Journal article; Peer reviewed, 2012)
      Purpose: The authors have studied the accuracy and robustness of a prototype electromagnetic window field generator (WFG) in an interventional radiology suite with a robotic C-arm. The overall purpose is the development ...
    • Airway segmentation and centerline extraction from thoracic CT - Comparison of a new method to state of the art commercialized methods 

      Reynisson, Pall Jens; Scali, Marta; Smistad, Erik; Hofstad, Erlend Fagertun; Leira, Håkon Olav; Lindseth, Frank; Hernes, Toril A. Nagelhus; Amundsen, Tore; Sorger, Hanne; Langø, Thomas (Peer reviewed; Journal article, 2015)
      Introduction Our motivation is increased bronchoscopic diagnostic yield and optimized preparation, for navigated bronchoscopy. In navigated bronchoscopy, virtual 3D airway visualization is often used to guide a bronchoscopic ...
    • Anthropomorphic liver phantom with flow for multimodal image-guided liver therapy research and training 

      Rethy, Anna; Sæternes, Jørn Ove; Halgunset, Jostein; Mårvik, Ronald; Hofstad, Erlend Fagertun; Sanchez-Margallo, Juan A.; Langø, Thomas (Journal article; Peer reviewed, 2017)
      Purpose The objective of this study was to develop a multimodal, permanent liver phantom displaying functional vasculature and common pathologies, for teaching, training and equipment development in laparoscopic ultrasound ...
    • Intraoperative localized constrained registration in navigated bronchoscopy 

      Hofstad, Erlend Fagertun; Sorger, Hanne; Bakeng, Janne Beate Lervik; Gruionu, Lucian; Leira, Håkon Olav; Amundsen, Tore; Langø, Thomas (Journal article; Peer reviewed, 2017)
      Purpose One of the major challenges in electromagnetic navigated bronchoscopy is the navigation accuracy. An initial rigid image-to-patient registration may not be optimal for the entire lung volume, as the lung tissue ...
    • Laboratory test of Single Landmark registration method for ultrasound-based navigation in laparoscopy using an open-source platform 

      Perez de Frutos, Javier; Hofstad, Erlend Fagertun; Solberg, Ole Vegard; Tangen, Geir Arne; Lindseth, Frank; Langø, Thomas; Elle, Ole Jacob; Mårvik, Ronald (Journal article; Peer reviewed, 2018)
      Purpose Test the feasibility of the novel Single Landmark image-to-patient registration method for use in the operating room for future clinical trials. The algorithm is implemented in the open-source platform CustusX, a ...
    • Lack of transfer of skills after virtual reality simulator training with haptic feedback 

      Våpenstad, Cecilie; Hofstad, Erlend Fagertun; Bø, Lars Eirik; Kuhry, Esther; Johnsen, Gjermund; Mårvik, Ronald; Langø, Thomas; Hernes, Toril A. Nagelhus (Journal article; Peer reviewed, 2017)
      Background and objective: Virtual reality (VR) simulators enrich surgical training and offer training possibilities outside of the operating room (OR). In this study, we created a criterion-based training program on a VR ...
    • Optimal timing of assessment tasks depending on experience level of surgical trainees 

      Våpenstad, Cecilie; Hofstad, Erlend Fagertun; Bernstein, Tor Eivind; Aadahl, Petter; Johnsen, Gjermund; Mårvik, Ronald (Peer reviewed; Journal article, 2019)
      Introduction: Box trainers with motion analysis are important add-ons to surgical training and skills assessment outside the operating room, given that they exhibit construct validity. Material and methods: Four different ...
    • Peripheral tumour targeting using open-source virtual bronchoscopy with electromagnetic tracking: a multi-user pre-clinical study 

      Jaeger, Herman Alexander; Trauzettel, Fabian; Nardelli, Pietro; Daverieux, Federico; Hofstad, Erlend Fagertun; Leira, Håkon Olav; Kennedy, Marcus P; Langø, Thomas; Cantillon-Murphy, Pádraig (Journal article; Peer reviewed, 2018)
      Objectives: The goal was to demonstrate the utility of open-source tracking and visualisation tools in the targeting of lung cancer. Material and methods: The study demonstrates the first deployment of the Anser electromagnetic ...
    • Psychomotor skills assessment by motion analysis in minimally invasive surgery on an animal organ 

      Hofstad, Erlend Fagertun; Våpenstad, Cecilie; Bø, Lars Eirik; Langø, Thomas; Kuhry, Esther; Mårvik, Ronald (Journal article; Peer reviewed, 2017)
      Background: A high level of psychomotor skills is required to perform minimally invasive surgery (MIS) safely. To be able to measure these skills is important in the assessment of surgeons, as it enables constructive ...
    • Pulmonologist evaluation on new CT visualization for guidance to lung lesions during bronchoscopy 

      Reynisson, Pall Jens; Leira, Håkon Olav; Langø, Thomas; Tangen, Geir Arne; Hatlen, Peter; Amundsen, Tore; Hofstad, Erlend Fagertun (Journal article; Peer reviewed, 2018)
      Objective: Endoluminal visualization in virtual and video bronchoscopy lacks information about the surrounding structures, and the traditional 2 D axial, coronal and sagittal CT views can be difficult to interpret. To ...
    • Ultrasound Contrast Imaging - Improved Tissue Suppression in Amplitude Modulation 

      Hofstad, Erlend Fagertun (Master thesis, 2006)
      The ability to image myocardial perfusion is very important in order to detect coronary diseases. GE Vingmed Ultrasound uses contrast agent in combination with a pulse inversion (PI) technique to do the imaging. But this ...
    • Ultrasound Contrast Imaging - Improved Tissue Suppression in Amplitude Modulation 

      Hofstad, Erlend Fagertun (Master thesis, 2006)
      The ability to image myocardial perfusion is very important in order to detect coronary diseases. GE Vingmed Ultrasound uses contrast agent in combination with a pulse inversion (PI) technique to do the imaging. But this ...
    • Using the CustusX toolkit to create an image guided bronchoscopy application: Fraxinus 

      Bakeng, Janne Beate Lervik; Hofstad, Erlend Fagertun; Solberg, Ole Vegard; Eiesland, Jon Wostryck; Tangen, Geir Arne; Amundsen, Tore; Langø, Thomas; Reinertsen, Ingerid; Selbekk, Tormod; Leira, Håkon Olav (Journal article; Peer reviewed, 2019)
      Purpose The aim of this paper is to show how a specialized planning and guidance application called Fraxinus, can be built on top of the CustusX platform (www.custusx.org), which is an open source image-guided intervention ...
    • Versatile robotic probe calibration for position tracking in ultrasound imaging 

      Bø, Lars Eirik; Hofstad, Erlend Fagertun; Lindseth, Frank; Hernes, Toril A. Nagelhus (Journal article; Peer reviewed, 2015)
      Within the field of ultrasound-guided procedures, there are a number of methods for ultrasound probe calibration. While these methods are usually developed for a specific probe, they are in principle easily adapted to other ...