case_images: PMC11342832_01
case_images: Reconstruction of DBS electrodes and programming. (A) Coronal and axial sections of the patient's MRI overlayed with the placement of the right and left DBS leads in the cZi, indicated as the red region. (B) Programming of the leads targeting the cZi, with monopolar activation of the right lead consisting of 70% L1 and 30% L2 ring mode contact, and the left lead consisting of 100% L1 contact. cZi caudal Zona incerta, STN subthalamic nucleus.
case_images: tohm-14-1-925-g1.jpg
case_images: PMC11342832_01_tohm-14-1-925-g1.jpg
case_images: F1
case_images: DBS settings. DBS contacts were chosen based on the modeling from the co-registration of post-operative MRI using BrainLab imaging software to precisely target the cZi (Figure 1A). The left lead consisted of 100% monopolar activation at contact L1, and the right lead consisted of 70% monopolar activation at contact L1, with 30% activation in ring mode at contact L2 (Figure 1B).
case_images: Ataxia and tremor assessments. (A) Postural sway area maps using APDM sensors with eyes open and feet apart for all conditions, demonstrating no drastic changes with the low-frequency stimulation as compared to baseline. (B) Similarly, with eyes closed and feet apart condition, no clear differences in sway measures were observed for the low- frequency stimulation conditions. (C-G) Speech audio spectrum for baseline, sham, 10 Hz, 15 Hz and 30 Hz stimulation conditions. (H) Acoustic voice quality index (AVQI) for all DBS stimulation conditions, depicting a reduction in AVQI for 30 Hz stimulation and showing an improvement in speech compared to other conditions. (I) A reduction in tremor amplitude was observed for the 30 Hz condition, as compared to baseline, sham and other low-frequency stimulation conditions. (J) Power spectral density (PSD) analysis also showed a reduction in spectral power at 30 Hz stimulation, indicating tremor reduction. Bsl baseline, Shm sham.
case_images: tohm-14-1-925-g2.jpg
case_images: PMC11342832_01_tohm-14-1-925-g2.jpg
case_images: F2
case_images: Consistently, we did not observe any effects of different low-frequency stimulation in postural sway measurements with eyes-open and eyes-closed while the patient stood on a firm surface (Figure 2A, B). Consistently, his speech analysis showed an improvement of AVQI with 30 Hz stimulation when compared to other stimulation conditions (AVQI scores: baseline: 4.00, sham: 3.91, 10 Hz: 3.97, 15 Hz: 4. 33, and 30 Hz: 3.19; lower number indicating a better speech clarity) (Figure 2C-H). Interestingly, we observed a reduction in hand tremor amplitude and normalized power spectral density for the 30 Hz stimulation condition as compared to baseline, sham and other low-frequency stimulation conditions (Figure 2I, J).