Abstracts

Functional Shift of Non-Verbal Memory Function After Selective Amygdalohippocampectomy by Magnetic Resonance Imaging-Guided Laser Interstitial Thermal Therapy

Abstract number : 3.451
Submission category : 9. Surgery / 9A. Adult
Year : 2023
Submission ID : 1436
Source : www.aesnet.org
Presentation date : 12/4/2023 12:00:00 AM
Published date :

Authors :
Presenting Author: Oliver Welp, Student – Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke University Magdeburg, Magdeburg, Germany

Hartmut Schütze, Dr. – Institute of Cognitive Neurology and Dementia Research, Otto-von-Guericke University Magdeburg, Magdeburg, Germany; Jörn Kaufmann, Dr. rer. nat. – Department of Medical Physics, Otto-von-Guericke University Magdeburg, Germany; Lars Büntjen, Dr. med. – Department of Stereotactic Neurosurgery, Otto-von-Guericke University Magdeburg, Germany; Jürgen Voges, Prof. Dr. med. – Department of Stereotactic Neurosurgery, Otto-von-Guericke University Magdeburg, Germany; Aiden Haghikia, MD – Department of Neurology, Otto-von-Guericke University Magdeburg, Germany; Emrah Düzel *, Prof. Dr. med. – German Center for Neurodegenerative Diseases (DZNE), Magdeburg, Germany; Friedhelm C. Schmitt *, MD – Department of Neurology, Otto-von-Guericke University Magdeburg, Germany

Rationale:
Magnetic resonance imaging-guided laser interstitial thermal therapy (MRgLITT) is an effective and minimal invasive procedure to treat drug resistant epilepsy.1 It has become a widespread method in the cure of mesial temporal lobe epilepsy (MTLE). Several questions remain open concerning the relationship between ablative brain volume and new cognitive function.4,5 Mapping after ablation enables to determine the functional shift before and after selective amygdalohippocampectomy (SAH) by MRgLITT.2,3 The aim is to display the postoperative changes in non-verbal memory processing. We present the results of an established non-verbal fMRI memory task3,5 after SAH by MRgLITT in a group of 13 patients with MTLE.

Methods:
The patients were measured within two weeks before and after SAH, respectively. The subjects were shown inside and outside pictures in black and white. The first measurement was a learning task in which all 144 pictures were displayed. After 30 minutes, a recall task took place, in which similar pictures from the previous task are mixed with new ones. Goal is to recognize familiar images in a scale from one to five. After preprocessing the data, a full factorial model was created to show with different contrasts the postoperative activations in the hippocampus and amygdala. The result maps were normalized into MNI space.

Results:
Figure 1 shows significant activations (t-test  p< 0.001) in the right hippocampus and amygdala after ablation. Increased activity is emphasized in the hippocampus and amygdala after surgery. The t-test was used to show a directional change with the focus on the postoperative changes. A f-test confirmed the results.
Surgery