Ventralis intermedius thalamotomy with focused ultrasound for patients with low skull density ratio

Yamamoto, Kazuaki; Itô, Hisashi; Fukutake, Shigeru; Kamei, Tetsumasa; Yamaguchi, Toshio; Taira, Takaomi

doi:10.1002/mds.27726

Cited by 18 publications

(16 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This relationship has been previously defined in the literature. [12][13][14][15][16][17][18] This same association was observed regarding aborted sonication because of unbearable headaches. Patients with a lower SDR and a higher ST could benefit from a more aggressive analgesic prophylaxis, including opioids.…”

Section: Discussionsupporting

confidence: 66%

Factors Associated with Headache and Nausea During Magnetic Resonance–Guided Focused Ultrasound for Tremor

Cacho‐Asenjo

Honorato‐Cia

Núñez‐Córdoba

et al. 2021

Movement Disord Clin Pract

View full text Add to dashboard Cite

BackgroundBackground: During magnetic resonance-guided focused ultrasound for essential or parkinsonian tremor, adverse events (headache, nausea/vomiting, or anxiety) may alter the outcome of the procedure despite being mostly transient and mild. Objectives Objectives: Our aim was to analyze the relationship between demographic, procedural, and anesthetic characteristics with magnetic resonance/ultrasound-related events. Methods Methods: This was a retrospective study at the Clinica Universidad de Navarra of patients undergoing thalamotomy with magnetic resonance-guided focused ultrasound between September 2018 and October 2019. The anesthesia protocol included headache and nausea/vomiting prophylaxis and rescue therapy. Dexmedetomidine was used for anxiolysis in some patients after thorough multidisciplinary assessment. Results Results: A total of 123 patients were included. Headache was directly related to skull density ratio (P < 0.001) and skull thickness (P = 0.02). Patients with a skull density ratio less than 0.48 had 3 times the odds of experiencing moderate or severe headache (odds ratio [OR], 3.08; 95% confidence interval [CI], 1.21-7.82) and had a higher odds of aborting sonication due to pain. Sex was associated with increased nausea (P = 0.007). Women had 4 times the odds of nausea than men (OR, 4.4; 95% CI, 1.61-12.11). Dexmedetomidine did not reduce headache or nausea incidence. Patients who received dexmedetomidine had a higher number (P = 0.01) and total minutes of sonication (P = 0.01). Conclusions Conclusions: Patients with lower skull density ratios and higher skull thicknesses could benefit from an aggressive analgesic prophylaxis. Women are more likely to experience nausea. Dexmedetomidine did not reduce headache and nausea, but increased the number and duration of sonications. Its exact effect on tremor is still unclear.

show abstract

Section: Discussionsupporting

confidence: 66%

Factors Associated with Headache and Nausea During Magnetic Resonance–Guided Focused Ultrasound for Tremor

Cacho‐Asenjo

Honorato‐Cia

Núñez‐Córdoba

et al. 2021

Movement Disord Clin Pract

View full text Add to dashboard Cite

show abstract

“…However, this study had shown that there were no significant differences in terms of clinical outcome and safety profile between patients with a low SDR (0.3-0.4) and those with a high SDR (>0.4). Similar reports of Japan and Korea also showed that patients with low SDR can be successfully treated (Chang et al, 2019;Yamamoto et al, 2019). As reported previously, 50% of Chinese and 78.6% of Japanese patients had SDRs of 0.40 or less (Yamamoto et al, 2019;Tsai et al, 2021).…”

Section: Discussionsupporting

confidence: 86%

Focused Ultrasound Thalamotomy for the Treatment of Essential Tremor: A 2-Year Outcome Study of Chinese People

Lin

et al. 2021

Front. Aging Neurosci.

Self Cite

View full text Add to dashboard Cite

Background: Essential tremor (ET) is a common movement disorder among elderly individuals worldwide and is occasionally associated with a high risk for mild cognitive impairment and dementia. This retrospective study aimed to determine the clinical outcome of unilateral magnetic resonance-guided focused ultrasound (MRgFUS) thalamotomy in Chinese patients with ET.Methods: In total, 31 male and 17 female patients with drug-refractory ET were enrolled in this research study from January 2017 to September 2019. The severity of tremor and disability were assessed using the Clinical Rating Scale for Tremor (CRST) within a 2-year follow-up period.Results: The mean age of the participants was 59.14 ± 13.5 years. The mean skull density ratio (SDR) was 0.5 ± 0.1. The mean highest temperature was 57.0 ± 2.4°C. The mean number of sonications was 10.0 ± 2.6. The average maximum energy was 19,710.5 ± 8,624.9 J. The total CRST scores and sub-scores after MRgFUS thalamotomy significantly reduced during each follow-up (p < 0.001). All but four (8.3%) of the patients had reversible adverse events (AEs) after the procedure.Conclusions: MRgFUS had sustained clinical efficacy 2 years after treatment for intractable ET. Only few patients presented with thalamotomy-related AEs including numbness, weakness, and ataxia for an extended period. Most Chinese patients were treated safely and effectively despite their low SDR.

show abstract

“…For this reason, the US Food and Drug Administration recommends an SDR of 0.45 or less as a contraindication for FUS treatment. 9,10) As reported previously, 78.6% of the study patients had SDRs of ≤0.40, 11) which makes maximization of heating efficiency a critical clinical issue. However, a strategy to maximize heating efficiency in FUS remains to be established.…”

Section: Introductionmentioning

confidence: 51%

“…[16][17][18] Because approximately 80% of the patients had SDRs of ≤0.40, efficient strategies were needed for achieving the highest possible temperature in the target. 11) Despite the documented difficulties, a study previously reported that FUS can be performed successfully for patients with ET and TDPD having low-SDR. 11) A later report on skull factors further suggested that patients with low SDR can be successfully treated.…”

Section: Discussionmentioning

confidence: 99%

See 1 more Smart Citation

Factors Associated with Heating Efficiency in Transcranial Focused Ultrasound Therapy

Yamamoto

Itô

Fukutake

et al. 2020

Neurol. Med. Chir.(Tokyo)

Self Cite

View full text Add to dashboard Cite

Transcranial magnetic resonance-guided focused ultrasound (FUS) therapy is a less invasive stereotactic treatment for tremor and other movement disorders. A sufficiently high temperature in the target brain tissue is crucial during ablation procedures for good outcomes. Therefore, maximizing the heating efficiency is critical in cases where high temperature cannot be achieved because of patient-related characteristics. However, a strategy to achieve the desired therapeutic temperature with FUS has not yet been established. This study aimed to investigate the procedural factors associated with heating efficiency in FUS. We retrospectively reviewed and analyzed data from patients who underwent FUS for ventralis intermedius (VIM) nucleus thalamotomy. In all, 30 consecutive patients were enrolled. 18 with essential tremor (ET), 11 with tremor-dominant Parkinson's disease (TDPD), and 1 with Holmes tremor. Multivariate regression analysis showed that decline in heating efficiency was associated with lower skull density ratio (SDR) and a greater subtotal rise in temperature until the previous sonication. To maximize heating efficiency, the temperature increase should be set to the least value in the target alignment and verification phases, and subsequently should be increased sufficiently in the treatment phase. This strategy may be particularly beneficial in cases where high ablation temperatures cannot be achieved because of patient-related characteristics. Importantly, a broad patient population would benefit from this strategy as it could reduce the need for high energy to achieve therapeutic temperatures, thereby decreasing the risks of adverse events.

show abstract

Ventralis intermedius thalamotomy with focused ultrasound for patients with low skull density ratio

Cited by 18 publications

References 3 publications

Factors Associated with Headache and Nausea During Magnetic Resonance–Guided Focused Ultrasound for Tremor

Factors Associated with Headache and Nausea During Magnetic Resonance–Guided Focused Ultrasound for Tremor

Focused Ultrasound Thalamotomy for the Treatment of Essential Tremor: A 2-Year Outcome Study of Chinese People

Factors Associated with Heating Efficiency in Transcranial Focused Ultrasound Therapy

Contact Info

Product

Resources

About