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72. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC)
Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgie

Deutsche Gesellschaft für Neurochirurgie (DGNC) e. V.

06.06. - 09.06.2021

The frontal aslant tract – is it resectable?

Der Frontal Aslant Tract – ist er resektabel?

Meeting Abstract

  • presenting/speaker Katharina Faust - Charité Universitätsmedizin, Klinik für Neurochirurgie, Berlin, Deutschland
  • presenting/speaker Ina Bährend - Charité Universitätsmedizin, Klinik für Neurochirurgie, Berlin, Deutschland
  • Peter Vajkoczy - Charité Universitätsmedizin, Klinik für Neurochirurgie, Berlin, Deutschland
  • Max Münch - Charité Universitätsmedizin, Klinik für Neurochirurgie, Berlin, Deutschland
  • Georg Bohner - Charité Universitätsmedizin, Klinik für Neurochirurgie, Berlin, Deutschland

Deutsche Gesellschaft für Neurochirurgie. 72. Jahrestagung der Deutschen Gesellschaft für Neurochirurgie (DGNC), Joint Meeting mit der Polnischen Gesellschaft für Neurochirurgie. sine loco [digital], 06.-09.06.2021. Düsseldorf: German Medical Science GMS Publishing House; 2021. DocP202

doi: 10.3205/21dgnc483, urn:nbn:de:0183-21dgnc4831

Veröffentlicht: 4. Juni 2021

© 2021 Faust et al.
Dieser Artikel ist ein Open-Access-Artikel und steht unter den Lizenzbedingungen der Creative Commons Attribution 4.0 License (Namensnennung). Lizenz-Angaben siehe http://creativecommons.org/licenses/by/4.0/.


Gliederung

Text

Objective: The Frontal Aslant Tract (FAT) has not been described until recently. It connects the inferior frontal gyrus with the supplementary- and pre-supplementary motor areas. Its functions have not been entirely elucidated yet, however, there is evidence that the left FAT may play a role in language function.

The aim of our study was to evaluate neurological outcomes after partial or total resection of the FAT, as well as the functional connectivity of the FAT to language positive cortical areas.

Methods: 23 patients, in which a partial resection of the left FAT was performed, were evaluated regarding their neurological outcomes. Out of those, 14 patients were operated awake and 9 under general anesthesia. In all patients, the FAT was visualized in both the pre-and postoperative MRIs, and the percentaged volume of FAT-resection was documented. Secondly, all patients were evaluated as regards their language function with the Aachen Aphasia Score (AAS) at 3 given time points: (1.) preoperatively, (2.) postoperatively and (3.) 3 months postoperatively. In addition, in 28 patients with tumors in the left perisylvian region, who were operated awake with direct electrical stimulation (DES), DTI fibertracing was performed from all DES postive language spots to visualize their potential integration into the FAT.

Results: Resection of the FAT had no immediate impact on the postoperative speech outcome in 87% of the patients. 13% showed a transient postoperative speech deterioration, which was associated with either semantic or dysarthric errors in the AAT. After 3 months, however, all FAT-resected patients showed a complete remission of their postoperative speech deficits.

Out of all 188 intraoperatively registered positive cortical language sites, only 15 sites integrated into the FAT. Those all originated from the frontal operculum. 11 originated from the pars triangularis, of which all consistently connected to pre-SMA; while 4 originated from the pars opercularis, of which all connected to SMA. As concerns the error categories connecting into the FAT, 47% were semantic errors, 27% anomias and 27% dysarthric errors.

Conclusion: While we did observe fiber-connections of language positive DES sites into the FAT, resection of the FAT did not result in permanent language deficits in any of the patients. It may thus be hypothesized that, while the FAT may play a contributory role within the language connectome, its role may not be essential for language function.