Does ultrasound-guidance improve the outcome of botulinum toxin injections in cervical dystonia?

Accurate targeting of overactive muscles is fundamental for successful botulinum neurotoxin (BoNT) injections in the treatment of spasticity. The necessity of instrumented guidance and the superiority of one or more guidance techniques are ambiguous. Here, we sought to investigate if guided BoNT injections lead to a better clinical outcome in adults with limb spasticity compared to non-guided injections. We also aimed to elucidate the hierarchy of common guidance techniques including electromyography, electrostimulation, manual needle placement and ultrasound. To this end, we conducted a Bayesian network meta-analysis and systematic review with 245 patients using the MetaInsight software, R and the Cochrane Review Manager. Our study provided, for the first time, quantitative evidence supporting the superiority of guided BoNT injections over the non-guided ones. The hierarchy comprised ultrasound on the first level, electrostimulation on the second, electromyography on the third and manual needle placement on the last level. The difference between ultrasound and electrostimulation was minor and, thus, appropriate contextualization is essential for decision making. Taken together, guided BoNT injections based on ultrasound and electrostimulation performed by experienced practitioners lead to a better clinical outcome within the first month post-injection in adults with limb spasticity. In the present study, ultrasound performed slightly better, but large-scale trials should shed more light on which modality is superior.

Section: Limitationsmentioning

confidence: 89%

Section: Introductionmentioning

confidence: 99%

A Bayesian Network Meta-Analysis and Systematic Review of Guidance Techniques in Botulinum Toxin Injections and Their Hierarchy in the Treatment of Limb Spasticity

Asimakidou

Sidiropoulos

2023

“…Bhidayasiri et al [ 16 ] presented a case series of three patients about whom they conclude the lack of deeply located muscles imaging led to BoNT-A treatment failure. There is only one study comparing directly US-guided and non-guided injections in two different groups of patients which found no difference [ 22 ]. An expert-statement published in 2015 [ 24 ] suggested that US-guided injections should be used especially in cases with specific anatomic conditions, such as pronounced or inaccessible neck muscles, obesity or muscle atrophy, during adverse events following BoNT-A treatment, complex dystonic patterns with involvement of deep cervical muscles, or in secondary non-responders.…”

Section: Discussionmentioning

confidence: 99%

“…Most of the studies have been performed in small groups of patients or were focused on injections into deep cervical muscles only [ 16 , 17 , 18 , 19 , 20 , 21 ]. There is only one recently published study directly comparing the results of US-guided and non-guided BoNT-A injections in two groups of patients [ 22 ]. Nevertheless, there are no randomized, controlled studies proving the higher effectiveness of US-guided versus blinded injections.…”

Section: Introductionmentioning

confidence: 99%

Does Ultrasound Guidance Improve the Effectiveness of Neurotoxin Injections in Patients with Cervical Dystonia? (A Prospective, Partially-Blinded, Clinical Study)

Tyślerowicz

Dulski

Gawryluk

et al. 2022

Aim: The aim of this study was to evaluate the efficacy of ultrasound guidance (US) in the treatment of cervical dystonia (CD) with botulinum neurotoxin type A (BoNT-A) injections in comparison to anatomical landmarks (AL). To date, US is routinely used in many centers, but others deny its usefulness. Materials and Methods: Thirty-five patients (12 males, 23 females) with a clinical diagnosis of CD were included in the study. Intramuscular administration of BoNT-A was performed using either US guidance, or with AL, in two separate therapeutic sessions. The efficacy of BoNT-A administration was assessed with the Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS), Tsui modified scale, Craniocervical Dystonia Questionnaire (CDQ-24) and Clinical Global Impression—Improvement scale (CGI-I). Additionally, patients at therapeutic sessions were digitally recorded and evaluated by two blinded and independent raters. Results: A significant decrease in total TWSTRS, severity subscale TWSTRS, Tsui score, and CDQ-24 was found in both the AL and US group; however, in the TWSTRS disability and pain subscales, a significant decrease was found only in the US group. Moreover, US guided treatment also resulted in a greater decrease in TWSTRS, Tsui score and CDQ-24 compared to anatomical landmarks use only. Conclusions: US guidance might be helpful in improving the results of BoNT-A injections in cervical dystonia, reducing associated pain and disability; however, more studies are needed to evaluate its clinical efficacy.

“…These results broadly mirrored those of a cadaveric study comparing US-guided and anatomically guided injections into cervical muscles, which demonstrated an accuracy of about 95–100% and of about 55–80%, respectively [ 52 ]. Although these findings would support the concept the inaccurate delivery of the BoNT might account for suboptimal or negative outcomes, only two studies have formally tested this hypothesis [ 53 , 54 ]. Thus, by comparing US-guided injections and injections guided by identification of anatomical landmarks, it was shown that Toronto Western Spasmodic Torticollis Rating Scale (TWSTRS) disability and pain subscales significantly decreased only in the former group and that the total TWSTRS and its severity subscale, as well as measures of quality of life, showed a greater reduction with US than in the group assigned to anatomically guided injections [ 53 ].…”

Section: Correct Injections–us/emgmentioning

confidence: 99%

Improving the Efficacy of Botulinum Toxin for Cervical Dystonia: A Scoping Review

Erro

Picillo

Pellecchia

et al. 2023

Cervical dstonia (CD) is a chronic disorder with a significant detrimental impact on quality of life, requiring long-term treatment. Intramuscular injections of botulinum neurotoxin (BoNT) every 12 to 16 weeks have become the first-line option for CD. Despite the remarkable efficacy of BoNT as a treatment for CD, a significantly high proportion of patients report poor outcomes and discontinue the treatment. The reasons that drive sub-optimal response or treatment failure in a proportion of patients include but are not limited to inappropriate muscle targets and/or BoNT dosing, improper method of injections, subjective feeling of inefficacy, and the formation of neutralizing antibodies against the neurotoxin. The current review aims to complement published research focusing on the identification of the factors that might explain the failure of BoNT treatment in CD, highlighting possible solutions to improve its outcomes. Thus, the use of the new phenomenological classification of cervical dystonia known as COL-CAP might improve the identification of the muscle targets, but more sensitive information might come from the use of kinematic or scintigraphic techniques and the use of electromyographic or ultrasound guidance might ensure the accuracy of the injections. Suggestions are made for the development of a patient-centered model for the management of cervical dystonia and to emphasize that unmet needs in the field are to increase awareness about the non-motor spectrum of CD, which might influence the perception of the efficacy from BoNT injections, and the development of dedicated rehabilitation programs for CD that might enhance its effectiveness.