title: Modelling dynamic fronto-parietal behaviour during minimally invasive surgery--a Markovian trip distribution approach.
abstract: Learning to perform Minimally Invasive Surgery (MIS) requires considerable attention, concentration and spatial ability. Theoretically, this leads to activation in executive control (prefrontal) and visuospatial (parietal) centres of the brain. A novel approach is presented in this paper for analysing the flow of fronto-parietal haemodynamic behaviour and the associated variability between subjects. Serially acquired functional Near Infrared Spectroscopy (fNIRS) data from fourteen laparoscopic novices at different stages of learning is projected into a low-dimensional 'geospace', where sequentially acquired data is mapped to different locations. A trip distribution matrix based on consecutive directed trips between locations in the geospace reveals confluent fronto-parietal haemodynamic changes and a gravity model is applied to populate this matrix. To model global convergence in haemodynamic behaviour, a Markov chain is constructed and by comparing sequential haemodynamic distributions to the Markov's stationary distribution, inter-subject variability in learning an MIS task can be identified.
authors.affiliation: Royal Society/Wolfson Medical Image Computing Laboratory, Department of Biosurgery and Surgical Technology, Imperial College London, United Kingdom. d.leff@imperial.ac.uk
authors.forename: Daniel Richard
authors.initials: DR
authors.lastname: Leff
authors.forename: Felipe
authors.initials: F
authors.lastname: Orihuela-Espina
authors.forename: Julian
authors.initials: J
authors.lastname: Leong
authors.forename: Ara
authors.initials: A
authors.lastname: Darzi
authors.forename: Guang-Zhong
authors.initials: GZ
authors.lastname: Yang
mesh_terms: D001931:Brain Mapping / Q000379:methods*; D003198:Computer Simulation; D005625:Frontal Lobe / Q000503:physiopathology / Q000601:surgery*; D006801:Humans; D008390:Markov Chains; D019060:Minimally Invasive Surgical Procedures / Q000379:methods*; D008959:Models, Neurological; D015233:Models, Statistical; D010296:Parietal Lobe / Q000503:physiopathology / Q000601:surgery*; D019265:Spectroscopy, Near-Infrared / Q000379:methods*; D025321:Surgery, Computer-Assisted / Q000379:methods*