Computer Graphics and Visualization • Publications

J Neurosci Methods

Stability metrics for optic radiation tractography: Towards damage prediction after resective surgery

Stephan Meesters, P.P.W. Ossenblok, L. Wagner, Olaf Schijns, Paul Boon, L.M.J. Florack, Anna Vilanova, and R. Duits

Left: An example of the reconstruction result of the OR using probabilistic tractography from an axial view. As inserts, close-ups are shown of the anterior tips of the reconstructions of the OR from a coronal view. Right: The tracking results are shown for the same volunteer in a composite image along with other brain structures such as the ventricular system. The ML-TP distance measurement is indicated.

An accurate delineation of the optic radiation (OR) using diffusion MR tractography may reduce the risk of a visual field deficit after temporal lobe resection. However, tractography is prone to generate spurious streamlines, which deviate strongly from neighboring streamlines and hinder a reliable distance measurement between the temporal pole and the Meyer's loop (ML-TP distance). Stability metrics are introduced for the automated removal of spurious streamlines near the Meyer's loop. Firstly, fiber-to-bundle coherence (FBC) measures can identify spurious streamlines by estimating their alignment with the surrounding streamline bundle. Secondly, robust threshold selection removes spurious streamlines while preventing an underestimation of the extent of the Meyer's loop. Standardized parameter selection is realized through test-retest evaluation of the variability in ML-TP distance. The variability in ML-TP distance after parameter selection was below 2 mm for each of the healthy volunteers studied (N = 8). The importance of the stability metrics is illustrated for epilepsy surgery candidates (N = 3) for whom the damage to the Meyer's loop was evaluated by comparing the pre- and post-operative OR reconstruction. The difference between predicted and observed damage is in the order of a few millimeters, which is the error in measured ML-TP distance. Comparison with existing method(s) The stability metrics are a novel method for the robust estimate of the ML-TP distance. The stability metrics are a promising tool for clinical trial studies, in which the damage to the OR can be related to the visual field deficit that may occur after epilepsy surgery.

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Citation

Stephan Meesters, P.P.W. Ossenblok, L. Wagner, Olaf Schijns, Paul Boon, L.M.J. Florack, Anna Vilanova, and R. Duits, Stability metrics for optic radiation tractography: Towards damage prediction after resective surgery, J Neurosci Methods, 288, pp. 34–44, 2017.

BibTex

@article{bib:meesters:2017,
    author       = { Meesters, Stephan and Ossenblok, P.P.W. and Wagner, L. and Schijns, Olaf and Boon, Paul and Florack, L.M.J. and Vilanova, Anna and Duits, R. },    
    title        = { Stability metrics for optic radiation tractography: Towards damage prediction after resective surgery },
    journal      = { J Neurosci Methods },
    volume       = { 288 },
    year         = { 2017 },
    pages        = { 34--44 },
    doi          = { 10.1016/j.jneumeth.2017.05.029 },
    pubmedid     = { 28648721 },
    url          = { https://publications.graphics.tudelft.nl/papers/250 },
}