Development of Parkinson's disease in patients with blepharospasm

Dystonia and Parkinson's disease: Do they have a shared biology?

Parkinsonism and dystonia co-occur across many movement disorders and are most encountered in the setting of Parkinson's disease. Here we aim to explore the shared neurobiological underpinnings of dystonia and parkinsonism through the clinical lens of the conditions in which these movement disorders can be seen together. Foregrounding the discussion, we briefly review the circuits of the motor system and the neuroanatomical and neurophysiological aspects of motor control and highlight their relevance to the proposed pathophysiology of parkinsonism and dystonia. Insight into shared biology is then sought from dystonia occurring in PD and other forms of parkinsonism including those disorders in which both can be co-expressed simultaneously. We organize these within a biological schema along with important questions to be addressed in this space.

Case report: Blepharospasm in peak-dose dyskinesia may benefit from amantadine in Parkinson's disease

Introduction

Blepharospasm is uncommon in Parkinson's disease, especially in the peak-dose dyskinesia period.

Case presentation

We herein present the case of a patient with PD who developed blepharospasm in the peak-dose dyskinesia period. The symptom was improved by taking amantadine.

Conclusion

The current report expands the phenomenology of peak-dose dykinesia in PD to include dystonic blepharospasm. This complication of levodopa therapy may respond to amantadine despite the dystonic appearance of movements.

Development of parkinsonism after long-standing cervical dystonia - A cohort

INTRODUCTION

Dystonia occurring in the context of parkinsonism is well-known, e.g. as foot dystonia in young-onset Parkinson's disease (PD), anterocollis in multisystem atrophy (MSA) or blepharospasm (levator inhibition) in progressive supranuclear palsy. We have, however, encountered a series of patients whose phenotype differed from the above described entities.

METHODS

We describe a cohort of patients in whom typical idiopathic isolated (primary) late-onset focal or segmental (predominantly cervical) dystonia preceded the development of parkinsonism by several years, sometimes decades.

RESULTS

In a cohort of 450 patients followed in our botulinum toxin injections clinic, we identified 11 (2.4%; 7 women) who developed parkinsonism at a median of 14 years after the onset of dystonia. Median age at onset of parkinsonism was 70 years (range 59-87), usually manifesting with a new tremor or a change of tremor pattern, complaints of 'slowing down' or new walking difficulties. Parkinsonism resembled PD in 5 (one pathologically confirmed); the remainder had atypical parkinsonism of MSA (n = 3) or indeterminate phenotype (n = 3).

CONCLUSION

The relatively frequent occurrence of parkinsonism after long-standing dystonia would suggest a link between the two, in line with evidence from other clinical reports, imaging studies, animal models and genetics. It appears that in some cases of dystonia this could be an antecedent manifestation of a syndrome with parkinsonism developing later, or be a risk factor for parkinsonism. In practice, it is important for clinicians to be alert to new symptoms/signs in patients with long-standing dystonia. From a research point of view, longitudinal case-control studies would be required to further investigate the link between long-standing dystonia and subsequent parkinsonism.

Treatment of Blepharospasm and Oromandibular Dystonia with Botulinum Toxins

Blepharospasm and oromandibular dystonia are focal dystonias characterized by involuntary and often patterned, repetitive muscle contractions. There is a long history of medical and surgical therapies, with the current first-line therapy, botulinum neurotoxin (BoNT), becoming standard of care in 1989. This comprehensive review utilized MEDLINE and PubMed and provides an overview of the history of these focal dystonias, BoNT, and the use of toxin to treat them. We present the levels of clinical evidence for each toxin for both, focal dystonias and offer guidance for muscle and site selection as well as dosing.

Influence of coffee drinking and cigarette smoking on the risk of primary late onset blepharospasm: evidence from a multicentre case control study

Prior coffee and smoking habits were investigated in a multicentre case control study involving 166 patients presenting with primary late onset blepharospasm (BSP), 228 hospital control patients with primary hemifacial spasm and 187 population control subjects from five Italian centres. Information on age at disease onset, smoking and coffee drinking status at the reference age and average number of cups of coffee drunk/cigarettes smoked per day reached high and similar test-retest reproducibility in case and control patients. Unadjusted logistic regression analysis yielded a significant inverse association of prior coffee drinking and cigarette smoking with case status for the control groups. After adjustment for age, sex, referral centre, disease duration, years of schooling and ever coffee drinking/cigarette smoking, as appropriate, the smoking estimate lacked significance whereas the association of coffee intake and BSP did not (cases vs hospital control patients: OR 0.37 (95% CI 0.20 to 0.67); cases vs population control subjects: OR 0.44 (95% CI 0.23 to 0.85)). The strength of the inverse association between BSP and coffee intake tended to increase with the average number of cups drunk per day. There was a significant correlation between age of BSP onset and number of cups per day (adjusted regression coefficient 1.73; p = 0.001) whereas no correlation was found with number of packs of cigarettes per day. Coffee drinking may be inversely associated with the development of primary BSP and this association may partly depend on the amount consumed.

Botulinum toxin in blepharospasm and oromandibular dystonia: comparing different botulinum toxin preparations

Amongst all regions of the body, the craniocervical region is the one most frequently affected by dystonia. Whilst blepharospasm--involuntary bilateral eye closure--is produced by spasmodic contractions of the orbicularis oculi muscles, oromandibular dystonia may cause jaw closure with trismus and bruxism, or involuntary jaw opening or deviation, interfering with speaking and chewing. Both forms of dystonia can be effectively treated with botulinum toxin injection. This article summarizes injection techniques in both forms of dystonia and compares doses, potency and efficacy of different commercially available toxins, including Botox, Dysport, Xeomin and Myobloc/NeuroBloc.