Meige syndrome secondary to basal ganglia injury: a potential cause of acute respiratory distress

[Secondary blepharospasm, analysis and pathophysiology of blepharospasm. French translation of the article]

PURPOSE

To localize the brain structures involved in blepharospasm.

MATERIALS AND METHODS

This is a retrospective consecutive series of brain MRI's of patients with secondary blepharospasm whose immediate past medical history included cerebrovascular accident or head trauma.

RESULTS

Six patients, including 4 with CVA with ischemic or hemorrhagic lesions of the thalamus and caudate nuclei and 2 with head trauma with contusive sequellae to the tectal plate and frontal cortical and cerebellar atrophy.

CONCLUSION

According to the literature, brain lesions associated with blepharospasm involve mainly the thalamus, head of the caudate nucleus, corpus striatum, globus pallidus, internal capsule, cerebral cortex and cerebellum. This study demonstrates that blepharospasm is associated with a lesion of a complex neural network - cortex-thalamus-globus pallidus-cortex - and does not correspond to a single, unique lesion. This network is connected with ascending and descending sensory-motor pathways and motor nuclei.

Secondary blepharospasm, analysis and pathophysiology of blepharospasm

PURPOSE

To localize the brain structures involved in blepharospasm.

MATERIALS AND METHODS

This is a retrospective consecutive series of brain MRI's of patients with secondary blepharospasm whose immediate past medical history included cerebrovascular accident or head trauma.

RESULTS

Six patients, including 4 with CVA with ischemic or hemorrhagic lesions of the thalamus and caudate nuclei and 2 with head trauma with contusive sequellae to the tectal plate and frontal cortical and cerebellar atrophy.

CONCLUSION

According to the literature, brain lesions associated with blepharospasm involve mainly the thalamus, head of the caudate nucleus, corpus striatum, globus pallidus, internal capsule, cerebral cortex and cerebellum. This study demonstrates that blepharospasm is associated with a lesion of a complex neural network - cortex-thalamus-globus pallidus-cortex - and does not correspond to a single, unique lesion. This network is connected with ascending and descending sensory-motor pathways and motor nuclei.

Network localization of cervical dystonia based on causal brain lesions

Cervical dystonia is a neurological disorder characterized by sustained, involuntary movements of the head and neck. Most cases of cervical dystonia are idiopathic, with no obvious cause, yet some cases are acquired, secondary to focal brain lesions. These latter cases are valuable as they establish a causal link between neuroanatomy and resultant symptoms, lending insight into the brain regions causing cervical dystonia and possible treatment targets. However, lesions causing cervical dystonia can occur in multiple different brain locations, leaving localization unclear. Here, we use a technique termed 'lesion network mapping', which uses connectome data from a large cohort of healthy subjects (resting state functional MRI, n = 1000) to test whether lesion locations causing cervical dystonia map to a common brain network. We then test whether this network, derived from brain lesions, is abnormal in patients with idiopathic cervical dystonia (n = 39) versus matched controls (n = 37). A systematic literature search identified 25 cases of lesion-induced cervical dystonia. Lesion locations were heterogeneous, with lesions scattered throughout the cerebellum, brainstem, and basal ganglia. However, these heterogeneous lesion locations were all part of a single functionally connected brain network. Positive connectivity to the cerebellum and negative connectivity to the somatosensory cortex were specific markers for cervical dystonia compared to lesions causing other neurological symptoms. Connectivity with these two regions defined a single brain network that encompassed the heterogeneous lesion locations causing cervical dystonia. These cerebellar and somatosensory regions also showed abnormal connectivity in patients with idiopathic cervical dystonia. Finally, the most effective deep brain stimulation sites for treating dystonia were connected to these same cerebellar and somatosensory regions identified using lesion network mapping. These results lend insight into the causal neuroanatomical substrate of cervical dystonia, demonstrate convergence across idiopathic and acquired dystonia, and identify a network target for dystonia treatment.

Secondary blepharospasm associated with structural lesions of the brain

BACKGROUND

Blepharospasm is a form of focal dystonia that manifests as repetitive involuntary closure of the eyes. The pathogenesis of blepharospasm and the neuroanatomic substrates involved are not fully understood. Dysfunction of the basal ganglia traditionally is presumed to be the main cause of most forms of dystonia, but a growing body of evidence suggests that a network of additional cortical and subcortical structures may be involved.

METHODS

The medical records of 1114 patients with blepharospasm seen over past 10 years at Emory University were reviewed to identify potentially contributing brain lesions. A systematic review of the published literature was also conducted to identify potentially contributing brain lesions.

RESULTS

Among patients with blepharospasm at Emory University, 18 had focal lesions on imaging studies available for review. The literature review revealed 25 articles describing 30 additional cases of blepharospasm associated with focal lesions. Among all 48 cases, lesions were found in multiple regions including the thalamus (n=12), lower brainstem (n=11), basal ganglia (n=9), cerebellum (n=9), midbrain (n=7), and cortex (n=1).

CONCLUSIONS

These data in combination with functional imaging studies of primary blepharospasm support a model in which a network of different regions plays a role in the pathogenesis of blepharospasm.

Respiratory disorders associated with dystonia

BACKGROUND

Respiratory difficulties are sometimes reported by patients with cranial-cervical and other forms of dystonia, but the nature or mechanisms of the breathing problems have not been well characterized.

CASE REPORT

We review 13 dystonic patients with various respiratory complaints and describe their symptoms and response to treatment, including botulinum toxin (BoNT) injections.

DISCUSSION

Gasping, stridor, interrupted flow of speech, paradoxical breathing, dyspnea on exertion, and other respiratory symptoms reported by patients suggest involvement of the upper airways, chest, and diaphragm. BoNT injections may be, at least partially, beneficial in some patients.

CONCLUSION

This series of patients draws attention to respiratory distress as a potentially serious, even life-threatening, complication of dystonia.

Meige's syndrome and hemichorea associated with hyperthyroidism

Movement disorders are known to be associated with hyperthyroidism. However, the association of Meige's syndrome and hemichorea with hyperthyroidism has not been reported. We describe a young Chinese woman with hyperthyroidism, who presented with a unique combination of Meige's syndrome and hemichorea in the left limbs. Both neurologic manifestations were preceded by symptoms of hyperthyroidism, and resolved following treatment with methimazole for hyperthyroidism. Nevertheless, the neurologic symptoms recurred when she stopped taking methimazole, but abated when she returned to a euthyroid state after additional treatment with methimazole. The evolution of her clinical course indicated that the involuntary movements were in association with hyperthyroidism. This case is the first report of Meige's syndrome and hemichorea in a patient with hyperthyroidism, which raises the likelihood that hyperthyroidism may be a cause of Meige's syndrome and hemichorea. Furthermore, it emphasizes the need for greater attention to thyroid function in those afflicted with involuntary movements in order to optimize clinical management.