Endoscopic Injection of the Longus Capiti Muscle in the Treatment of Dystonic Head Flexion

Breathing dystonia in Meige syndrome

Background

Dyspnoea is rarely mentioned in the clinical description of adult-onset isolated dystonia. In this study, we present the clinical features of 13 patients with Meige syndrome (cranio-cervical dystonia) with breathing difficulties.

Methods

A retrospective case note review was performed of patients presenting with Meige syndrome and shortness of breath, to a neuro-laryngology MDT clinic.

Results

Some patients were severely limited by their breathlessness, but others did not volunteer these symptoms. The majority of patients were referred with the assumption that the larynx was the cause of the problem; however half the patients did not have evidence of laryngeal involvement. Of the patients who had laryngeal involvement, injecting the larynx alone did not always relieve the dyspnoea. The majority of our patients responded to injection of the suprahyoid muscles, including genioglossus, digastric and mylohyoid.

Conclusion

We recommend routinely establishing if the patient with Meige syndrome has signs or symptoms of breathlessness, and establishing the level of the problem, as this can be treated successfully.

Botulinum toxin treatment of dystonic anterocollis: What to inject

BACKGROUND

Anterocollis (AC) is a rare form of cervical dystonia, which responds poorly to botulinum toxin treatment.

OBJECTIVES

To recognise the different clinical phenotypes of AC and to detail the selection of muscles from the results of treating a cohort of 15 AC patients with Botulinum Toxin.

METHODS

The study was performed using prospectively collected data. We included 15 patients with cervical dystonia and AC posture, treated between 2016 and 2019 in our joint Neuro-ENT clinic. We excluded patients with posterior cervical muscle weakness and patients with Parkinsonism. We characterised the primary dystonic posture of every AC patient as posterior sagittal shift, head flexion or neck flexion, or a combination of the three.

RESULTS

All AC patients had a more widespread dystonic picture with a majority having Meige syndrome, but AC was the most problematic feature. Treatment with botulinum toxin required the injection not only of the deep cervical flexor (DCF), but also the sterno-cleido-mastoid (SCM) and moreover the supra-hyoid (SH) muscles. The choice between the longus capiti and the longus colli depended on the AC posture. Half of the patients had a dramatic improvement with 90% satisfaction or above.

CONCLUSION

AC posture is a complex but treatable type of CD. A joint Neuro-ENT clinic is an ideal setting in which to target all the dystonic muscles. This allows the injection of the longus capiti (under nasal endoscopic approach) as well as the supra-hyoid and SCM muscles in the same session.

A methodological approach for botulinum neurotoxin injections to the longus colli muscle in dystonic anterocollis: A case series of 4 patients and a literature review

We review the current approaches and their feasibility to treat dystonic anterocollis by injecting longus colli muscle (LCo) with botulinum neurotoxin (BoNT) as well as present our personal experiences in this field compared with the findings from previously published studies. First, we searched the PubMed database for the publications reporting patients who received LCo injections for anterocollis; we also thoroughly examined the references included in each of the found publications. Second, we present and analyze our own experiences in injecting LCo under EMG guidance in patients with dystonic anterocollis due to heredodegenerative disorders. We found 11 publications describing administration of LCo injections for the treatment of dystonic anterocollis in a total of 28 patients with primary dystonia aged between 21 and 80 years. The mean age of our patients was 44.8 years with the mean anterocollis duration being 15 months. OnabotulinumtoxinA in a dose of up to 35 U per LCo muscle was not associated with the development of transient dysphagia. The mean percentage of patient satisfaction was 36.3%, and the mean duration of the beneficial effect was 2.5 months. All patients agreed to receive a repeat injection. We provide a set of empirically based suggestions on the current use of BoNT injections to LCo for managing anterocollis in outpatient clinics, including pretreatment work-up, injection technique, and dose range.

Ultrasound Study to Validate the Anterior Cervical Approach to the Longus Colli Muscle Using Electromyography Control Alone

Background:

One of the main difficulties in the treatment of dystonic anterocollis is the injection of the deep flexor muscles of the neck such as Longus Colli (LCo). The injection of the LCo has been regarded as difficult and potentially dangerous; since we published our anterior median approach, a number of questions about the precision and the safety of our technique have been raised by colleagues.

Methods:

7 patients with anterocollis were injected, using our injection technique and when the needle was deemed to be in place, we used the ultrasound probe to determine what the needle had passed through, the depth of the tip of the needle and if the identified muscle was indeed LCo.

Results:

On the ultrasound section the LCo muscle is between 24 and 28 mm deep in the patients examined in this study. The location of the needle was confirmed by ultrasound and in most cases the needle was placed in the right axis but sometimes not deep enough. The EMG control made it possible to correct the depth in all cases. In most of the injections the needle traversed the thyroid. No acute incident occurred by this route of injection. Injections were performed between 22 and 28 mm deep.

Discussion:

From this study and based on a review of complications over 9 years experience with injecting LCo under EMG control using an anterior approach, we conclude that this technique is precise, safe and well tolerated.

Summary (Highlights):

The injection of the Longus Coli muscle for anterocollis has been regarded as difficult and potentially dangerous. This study showed, using ultrasound to determine the needle trajectory, that the anterior approach using EMG control is a precise, safe and well tolerated technique.