Thermography mapping patterns in temporal lobe epilepsy surgery

Enrique de Font-Réaulx; Javier Terrazo Lluch; Ramón López López; Paul Shkurovich Bialik; Miguel Ángel Collado Corona; Luis Guillermo Díaz López; Emilio Arch Tirado; Ernesto Ramírez Navarrete; Adalberto González Astiazarán

doi:10.25259/SNI_549_2019

Thermography mapping patterns in temporal lobe epilepsy surgery

Surg Neurol Int. 2020 Feb 28:11:30. doi: 10.25259/SNI_549_2019. eCollection 2020.

Authors

Enrique de Font-Réaulx¹, Javier Terrazo Lluch¹, Ramón López López², Paul Shkurovich Bialik³, Miguel Ángel Collado Corona³, Luis Guillermo Díaz López⁴, Emilio Arch Tirado⁵, Ernesto Ramírez Navarrete⁶, Adalberto González Astiazarán⁶

Affiliations

¹ Departments of Neurosurgery, ABC Medical Center, Mexico.
² Department of Neurorsurgery, La Raza UMAE, Social Security Mexican Institute, Mexico.
³ Departments of Neurophysiology, ABC Medical Center, Mexico.
⁴ Department of Neuroanesthesiology, National Institute of Neurology and Neurorurgery, Mexico City, Mexico.
⁵ Neurological Center, ABC Medical Center, Mexico, Cuidad de Mexico.
⁶ Pediatric Neurology, Epilepsy Clinic, ABC Medical Center, Mexico.

Abstract

Background: In several epilepsy etiologies, the macroscopic appearance of the epileptogenic tissue is identical to the normal, which makes it hard to balance between how much cytoreduction or disconnection and brain tissue preservation must be done. A strategy to tackle this situation is by evaluating brain metabolism during surgery using infrared thermography mapping (IrTM).

Methods: In 12 epilepsy surgery cases that involved the temporal lobe, we correlated the IrTM, electrocorticography, and neuropathology results.

Results: Irritative zones (IZ) had a lower temperature in comparison to the surrounding cortex with normal electric activity (difference in temperature (ΔT) from 1.2 to 7.1, mean 3.40°C standard deviation ± 1.61). The coldest zones correlated exactly with IZ in 9/10 cortical dysplasia (CD) cases. In case 3, the coldest area was at 1 cm away from the IZ. In 10/10 dysplasia cases (cases 1-4, 6-11), there was a radial heating pattern originating from the coldest cortical point. In 2/2 neoplasia cases, the temporal lobe cortical temperature was more homogeneous than in the CD cases, with no radial heating pattern, and there were no IZ detected. In case 8, we found the coldest IrTM recording in the hippocampus, which correlated to the maximal irritative activity recorded by strip electrodes. The ΔT is inversely proportional to epilepsy chronicity.

Conclusion: IrTM could be useful in detecting hypothermic IZ in CD cases. As the ΔT is inversely proportional to epilepsy chronicity, this variable could affect the metabolic thermic patterns of the human brain.

Keywords: Cortical dysplasia; Electrocorticography; Epilepsy surgery; Functional mapping; Hypothermic irritative zone; Infrared thermography brain mapping; Refractory epilepsy; Thermography patterns.