2026 Poster Presentations
P352: QUANTITATIVE ANATOMICAL COMPARISON OF THE CONTRA-LATERAL TRANSCALLOSAL IPSILATERAL TRANSCHOROIDAL AND CONTRA-LATERAL TRANSCALLOSAL CONTRA-LATERAL TRANSCHOROIDAL APPROACHES TO THE MEDIAL THALAMUS.
Irakliy Abramov; Kivanc Yangi; Egemen Gok; Mark C Preul; Michael T Lawton; Barrow Neurological Institute
Approach to lesions of the medial thalamus is challenging, and is dependent on lesion characteristics and location. Two approaches, the contra-lateral transcallosal ipsilateral transchoroidal (cTCal-iTChor) and the contra-lateral transcallosal contra-lateral transchoroidal (cTCal-cTChor) were compared in this study with respect to the best exposure of the medial thalamus.
METHODS: Three formalin-fixed human cadaveric heads (6 sides) were examined microsurgically by the aforementioned approaches and compared using the navigation system. Multiple polygons of exposed sections of the medial thalamus were assessed to calculate area of exposure. Surgical freedom at different regions of the medial thalamus, as well as angle of attack to the center of the medial thalamus were compared to study the advantages and drawbacks of the compared approaches.
RESULTS: The exposed areas of the superior (mean [± SD] 80 ± 32 vs 23.5± 13 mm2 , p=0.02), anterior (47.8 ± 27 vs 23 ± 7 mm2 , p=0.03), posterior (59.2 ± 21 vs 33.7 ± 16 mm2 , p=0.04), and total area (188 ± 45 vs 103 ± 33 mm2 , p=0.001) were significantly larger in cTCal-iTChor compared to cTCal-cTChor. Volume of surgical freedom was advantageous via the cTCal-iTChor compared to cTCal-cTChor at the postero-superior and antero-superior regions of the medial thalamus, 38 ± 10 vs 17 ± 12 mm3 , p=0.04 and 39.3 ± 19.3 vs 3 ± 8 mm3 ,p=0.01 respectively. CTCal-cTChor afforded significantly larger angle of attack to the surface of the medial thalamus compared to cTCal-iTChor, 25 ± 6 vs 17 ± 2 degrees, p<0.001, respectively
CONCLUSIONS: The cTCal-iTChor approach is preferable for exposure of medial thalamic lesions located at the velar surface of the thalamus. Both approaches described relatively similar surgical freedom at the medial thalamus. Considering the larger angle of attack to the surface of the thalamus in cTCal-cTChor, it is more advantageous in exposing lesions of the medial thalamus located at the inferior regions of the medial thalamus and extending in the medial-lateral direction.
