Table 1.
ALT—Anterior left temporal, BL—Bilateral left, RF—Right frontal, RT—Right temporal, LO—Left occipital, LF—Left frontal, LP—Left perirolandic, MTS—Mesial temporal sclerosis, CP—complex-partial, CPG—complex partial with secondary generalization, GA—Generalized atonic, SP—Simple partial, NF—No follow-up, NR—No resection.
Fig 1.
Localization results for data-sets I001_P034_D01 to Study_010.
The EOI nodes are marked by a bold annulus, whereas the nodes detected by our proposed algorithm are marked by solid brown circles. (a) (Top left) Localization results for data-set I001_P034_D01. This is a successful localization, with Vp = 0. Note that in in this data-set, even though node 6A–6B are mentioned in the report, their recordings are missing from the data-set. (b) (Top right) Localization results for data-set Study_004-2. This is a successful localization, with Vp = 0. (c) (Bottom left) Localization results for data-set Study_006. This is a successful localization, with Vp = 0.069. (d) (Bottom right) Localization results for data-set Study_010. This is a successful localization, with Vp = 0.071.
Fig 2.
Localization results for data-sets Study_016 to Study_027.
The EOI nodes are marked by a bold annulus, whereas the nodes detected by our proposed algorithm are marked by solid brown circles. (a) (Top left) Localization results for data-set Study_016. This is a successful localization, with Vp = 0.064. (b) (Top right) Localization results for data-set Study_017. This is a successful localization, with Vp = 0. (c) (Middle left) Localization results for data-set Study_020. This is a successful localization, with Vp = 0. (d) (Middle right) Localization results for data-set Study_021. This is a successful localization, with Vp = 0. (e) (Bottom left) Localization results for data-set Study_022. This is a successful localization, with Vp = 0. (f) (Bottom right) Localization results for data-set Study_027. This is a successful localization, with Vp = 0.
Fig 3.
Localization results for data-sets Study_023 to HUP64_phaseII.
The EOI nodes are marked by a bold annulus, whereas the nodes detected by our proposed algorithm are marked by solid brown circles. (a) (Top left) Localization results for data-set Study_023. This is a non-successful localization, with Vp = 0.143. (b) (Top right) Localization results for data-set Study_033. This is a successful localization, with Vp = 0.02. (c) (Bottom left) Localization results for data-set Study_037. This is a successful localization, with Vp = 0.051. (d) (Bottom right) Localization results for data-set HUP64_phaseII. This is a non-successful localization, with Vp = 0.071.
Fig 4.
Localization results for data-sets HUP65_phaseII to HUP78_phaseII.
The EOI nodes are marked by a bold annulus, whereas the nodes detected by our proposed algorithm are marked by solid brown circles. (a) (Top left) Localization results for data-set HUP65_phaseII. This is a successful localization, with Vp = 0. (b) (Top right) Localization results for data-set HUP65_phaseII. This is a successful localization, with Vp = 0. (c) (Bottom left) Localization results for data-set HUP70_phaseII. This is a successful localization, with Vp = 0. (d) (Bottom right) Localization results for data-set HUP78_phaseII. This is a successful localization, with Vp = 0.053.
Fig 5.
Localization results for data-set HUP87_phaseII.
The EOI nodes are marked by a bold annulus, whereas the nodes detected by our proposed algorithm are marked by solid brown circles. This is a successful localization, with Vp = 0.037.
Fig 6.
Heat maps illustrating the estimated causal influence graph for data-sets HUP65_phaseII and HUP70_phaseII.
The left column corresponds to the first 10 seconds in the ictal blocks, while the two right columns correspond to two random 10 seconds rest blocks. (a)-(c) Heat maps of data set HUP65_phaseII. (d)-(f) Heat maps of data set HUP70_phaseII.
Fig 7.
Heat maps illustrating the estimated causal influence graph for data-sets HUP78_phaseII and HUP87_phaseII.
The left column corresponds to the first 10 seconds in the ictal blocks, while the two right columns correspond to two random 10 seconds rest blocks. (a)-(c) Heat maps of data set HUP78_phaseII. (d)-(f) Heat maps of data set HUP87_phaseII.
Table 2.
Summarized localization results for different graph estimation methods.
GC refers to estimating the graph using only Granger causality, DI refers to estimating the graph using only k-NN DI estimation, and Proposed Algorithm refers to the algorithm proposed in the current paper. FPR refers to average false positive detection rate.
Table 3.
Summarized localization results for different inference methods.
Net-flow refers to the inference algorithm used in [16, 17]. Top 5% refers to choosing the nodes with the highest scores (top 5%). In both cases the graph is estimated using the methodology of the proposed algorithm. Proposed Algorithm refers to the algorithm proposed in the current paper. FPR refers to average false positive detection rate.
Fig 8.
Heat maps illustrating the estimated causal influence graph for data-set HUP65_phaseII in different time intervals.
(a) Heat map of the causal influence graph estimated from a rest block. (b) Heat map of the causal influence graph estimated from 10 seconds before a seizure (pre-ictal block). (c) Heat map of the causal influence graph estimated from a 10 seconds at the beginning of a seizure (ictal block). (d) Heat map of the causal influence graph estimated from 10-20 seconds after the beginning of a seizure. (e) Heat map of the causal influence graph estimated from 20-30 seconds after the beginning of a seizure. (f) Heat maps of the causal influence graph estimated from 30-40 seconds after the beginning of a seizure.
Fig 9.
High-level block diagram of the proposed algorithm.
and
are the inferences (set of electrodes) from the DI-Graph and the GC-Graph, respectively; ϕ denotes the empty set; and
is the final set of inferred electrodes.
Table 4.
Summarized localization results for different window lengths.
FPR refers to average false positive detection rate.
Fig 10.
Exemplary recorded signals for data-set Study_016.
The sampling rate is 500 Hz, while the block length is 10 seconds. (a) An ictal block. (b) A (randomly sampled) rest block.
Fig 11.
A block diagram of the procedure for calculating (or
).
is a 10 ⋅ Fs × N matrix of the ECoG recordings;
is a matrix of the pre-processing output;
is the estimated causal-influence graph (of size N × N); s is the vector of scores generated by the (variant of the) PageRank ranking process;
is a 2000 ⋅ Fs × N matrix used to create the empirical distributions; and,
is a set of electrodes inferred to be the SOZ.
Fig 12.
Ilustration of the the procedure for generating the empirical distributions for each node.
, denotes the empirical distribution of the jth node.