The Centre has a long history of developing new techniques for medical imaging (particularly in magnetic resonance imaging), transforming them from a primarily diagnostic modality into an interventional and therapeutic platform. This is facilitated by the Centre's strong engineering background in practical imaging and image analysis platform development, as well as advances in minimal access and robotic assisted surgery. Hamlyn has a strong tradition in pursuing basic sciences and theoretical research, with a clear focus on clinical translation.

In response to the current paradigm shift and clinical demand in bringing cellular and molecular imaging modalities to an in vivo – in situ setting during surgical intervention, our recent research has also been focussed on novel biophotonics platforms that can be used for real-time tissue characterisation, functional assessment, and intraoperative guidance during minimally invasive surgery. This includes, for example, SMART confocal laser endomicroscopy, time-resolved fluorescence spectroscopy and flexible FLIM catheters.


Search or filter publications

Filter by type:

Filter by publication type

Filter by year:

to

Results

  • Showing results for:
  • Reset all filters

Search results

  • Journal article
    Constantinescu MAM, Lee S, Navkar NV, Yu W, Al-Rawas S, Abinahed J, Zheng G, Keegan J, Al-Ansari A, Jomaah N, Landreau P, Yang GZet al., 2016,

    Constrained Statistical Modelling of Knee Flexion from Multi-Pose Magnetic Resonance Imaging

    , IEEE Transactions on Medical Imaging, Vol: 35, Pages: 1686-1695, ISSN: 1558-254X

    Reconstruction of the anterior cruciate ligament (ACL) through arthroscopy is one of the most common procedures in orthopaedics. It requires accurate alignment and drilling of the tibial and femoral tunnels through which the ligament graft is attached. Although commercial computer-assisted navigation systems exist to guide the placement of these tunnels, most of them are limited to a fixed pose without due consideration of dynamic factors involved in different knee flexion angles. This paper presents a new model for intraoperative guidance of arthroscopic ACL reconstruction with reduced error particularly in the ligament attachment area. The method uses 3D preoperative data at different flexion angles to build a subject-specific statistical model of knee pose. To circumvent the problem of limited training samples and ensure physically meaningful pose instantiation, homogeneous transformations between different poses and local-deformation finite element modelling are used to enlarge the training set. Subsequently, an anatomical geodesic flexion analysis is performed to extract the subject-specific flexion characteristics. The advantages of the method were also tested by detailed comparison to standard Principal Component Analysis (PCA), nonlinear PCA without training set enlargement, and other state-of-the-art articulated joint modelling methods. The method yielded sub-millimetre accuracy, demonstrating its potential clinical value.

  • Conference paper
    Zhao L, Giannarou S, Lee S, Merrifield R, Yang GZet al., 2016,

    Intra-operative simultaneous catheter and environment modelling for endovascular navigation based on intravascular ultrasound, electromagnetic tracking and pre-operative data

    , The Hamlyn Symposium on Medical Robotics, Publisher: The Hamlyn Symposium on Medical Robotics, Pages: 76-77
  • Conference paper
    Zhou X, Ernst S, Lee S, 2016,

    Path planning for robot-enhanced cardiac radiofrequency catheter ablation

    , IEEE International Conference on Robotics and Automation, Publisher: IEEE

    Radiofrequency Catheter Ablation (RFCA) is aprocedure used to treat cardiac arrhythmias by burning atregions of the endocardial walls to prevent the abnormalelectrical circuits causing the problem. Patients with AdultCongenital Heart Disease (ACHD) who have undergone surgicaltreatments suffer scarring within the heart that can lead to ab-normal cardiac rhythms. However, poor intraoperative cardiacgeometry recovery and incomplete Electrophysiological (EP)mapping due to limited available procedure time and complexanatomy have resulted in difficulty to detect the regions toablate and hence relatively high recurrence rates. In this paper,we present a catheter path planning algorithm to optimisecardiac EP mapping. Firstly, the optimal mapping positions aredetermined by curvature and distance weighted Quadric ErrorMetric Simplification (QEMS) to maximally recover the cardiacchamber geometry and EP mapping. Secondly, an efficient pathis designed that moves along a predetermined axis for a roboticcatheter to pass through and collect EP data at these positions.Validation is performed on retrospectively collected CARTOdata from ACHD patients.

  • Journal article
    Lee S, Aguib H, Chapron J, Bahmanyar R, Borghi A, Murphy O, McLeod C, ElGuindy A, Yacoub Met al., 2016,

    Spatial Orientation and Morphology of the Pulmonary Artery: Relevance to Optimising Design and Positioning of a Continuous Pressure Monitoring Device

    , Journal of Cardiovascular Translational Research, Vol: 9, Pages: 239-248, ISSN: 1937-5387

    Personalised treatment of heart disease requires an understanding of the patient-specific characteristics,which can vary over time. A newly developed implantable surface acoustic wave pressure sensor, capable ofcontinuous monitoring of the left ventricle filling pressure, is a novel device for personalised management ofpatients with heart disease. However, a one-size-fits-all approach to device sizing will affect its positioningwithin the pulmonary artery and its relationship to the interrogating device on the chest wall on a patientspecificlevel. In this paper, we analyse the spatial orientation and morphology of the pulmonary artery and itsmain branches in patients who could benefit from the device and normal controls. The results could optimisethe design of the sensor, its stent, and importantly its placement, ensuring long-term monitoring in patientgroups.

  • Journal article
    Giannarou S, Ye M, Gras G, Leibrandt K, Marcus HJ, Yang GZet al., 2016,

    Vision-based deformation recovery for intraoperative force estimation of tool–tissue interaction for neurosurgery

    , International Journal of Computer Assisted Radiology and Surgery, Vol: 11, Pages: 929-936, ISSN: 1861-6410

    Purpose In microsurgery, accurate recovery of the deformationof the surgical environment is important for mitigatingthe risk of inadvertent tissue damage and avoiding instrumentmaneuvers that may cause injury. The analysis of intraoperativemicroscopic data can allow the estimation of tissuedeformation and provide to the surgeon useful feedbackon the instrument forces exerted on the tissue. In practice,vision-based recovery of tissue deformation during tool–tissue interaction can be challenging due to tissue elasticityand unpredictable motion.Methods The aim of this work is to propose an approachfor deformation recovery based on quasi-dense 3D stereoreconstruction. The proposed framework incorporates a newstereo correspondence method for estimating the underlying3D structure. Probabilistic tracking and surface mapping areused to estimate 3D point correspondences across time andrecover localized tissue deformations in the surgical site.Results We demonstrate the application of this method toestimating forces exerted on tissue surfaces. A clinically relevantexperimental setup was used to validate the proposedframework on phantom data. The quantitative and qualitativeperformance evaluation results show that the proposed3D stereo reconstruction and deformation recovery methodsachieve submillimeter accuracy. The force–displacementmodel also provides accurate estimates of the exerted forces.Conclusions A novel approach for tissue deformationrecovery has been proposed based on reliable quasi-densestereo correspondences. The proposed framework does notrely on additional equipment, allowing seamless integration with the existing surgical workflow. The performanceevaluation analysis shows the potential clinical value of thetechnique.

This data is extracted from the Web of Science and reproduced under a licence from Thomson Reuters. You may not copy or re-distribute this data in whole or in part without the written consent of the Science business of Thomson Reuters.

Request URL: http://wlsprd.imperial.ac.uk:80/respub/WEB-INF/jsp/search-t4-html.jsp Request URI: /respub/WEB-INF/jsp/search-t4-html.jsp Query String: id=757&limit=5&page=2&respub-action=search.html Current Millis: 1590538367548 Current Time: Wed May 27 01:12:47 BST 2020