Clinical heterogeneity in patients with idiopathic blepharospasm: A cluster analysis.

BACKGROUND: Idiopathic blepharospasm is a clinically heterogeneous condition. It is not known whether the various manifestations become manifest sequentially during the course of the disease or aggregate in separate clusters identifying subpopulations of patients. METHODS: Eighty-nine patients with idiopathic blepharospasm were assessed using k-means cluster analysis to identify relatively homogeneous groups on the basis of low-intragroup/high-intergroup differences across a set of selected variables. RESULTS: The results suggest that there may be three groups of patients. Group 1 included patients who had prolonged muscle spasms leading to complete rim closure associated with brief and/or prolonged spasms with incomplete rim closure, the most severe blepharospasm, and a greater tendency to spread to adjacent segments. Group 2 included patients characterized by prolonged spasms with partial rim closure, either alone or associated with brief spasms whereas Group 3 included patients with brief spasms with complete rim closure, the least severe blepharospasm, and the lowest tendency to spread. The severity of Group 2 blepharospasm was between that observed in Group 1 and Group 3, while the tendency to spread was similar to Group 3. The three groups did not differ for disease duration, age of onset, sex and other clinical features. The observation that inhibition of the R2 component of the blink reflex recovery cycle was more abnormal in Groups 1/2 2 than in Group 3 at least in part validates our classification. CONCLUSIONS: The present study suggests that blepharospasm patients may be classified in different subtypes according to the type of spasms, severity of the condition and tendency to spread.

[Meige's syndrome or segmental craniocervical dystonia: terminology, history and contemporary view].

The term "Meige's syndrome" or "Breughel's syndrome" is used by specialists for the description of blepharospasm with the involuntary movements in the lower part of the face and/or masseter muscle. These eponyms "Meige's syndrome" and "Breughel's syndrome" make some mess in the terminology. The term "segmental craniocervical dystonia" joins different blepharospam-plus phenotypes and reflects contemporary perceptions about its genetic and pathophysiological community. Botulinotherapy is in fact the only way of symptomathic treatment of craniocervical dystonias.

Botulinum toxin and blink rate in patients with blepharospasm and increased blinking.

OBJECTIVE: The aim of the study was to investigate the effect of botulinum toxin (BoNT) on blink rate (BR) in patients with blepharospasm (BSP) and increased blinking (IB). METHODS: 37 patients with a clinical diagnosis of primary BSP (19 patients had tonic orbicularis oculi (OO) spasms and 18 patients had clonic OO spasms) and 8 patients with IB were included in this case-control study. All subjects underwent a standardised video protocol and clinical evaluation with a validated questionnaire designed to identify eye symptoms and Blepharospasm Disability Index (BSDI) before and 1 month after BoNT injection. BR was measured from the video recording before and after BoNT. BR in BSP and IB patients was compared with that from a group of healthy subjects and from a group of patients with hemifacial spasm (HFS). BR in HFS was also measured before and after BoNT. RESULTS: BR was increased in patients with IB and in BSP patients with clonic spasms but not in BSP patients with tonic spasms. BoNT reduced BR in patients with IB and in patients with clonic spasms, but not in patients with tonic spasms. BoNT left BR in patients with HFS unchanged. Changes in BR after BoNT were also independent of the presence of ocular symptoms. Despite the differential response of BR, BoNT significantly reduced BSDI in patients with BSP and IB. CONCLUSIONS: BoNT differentially modulates BR in patients with BSP and IB depending on the baseline BR. BoNT injection reduces BR only when the blink generator is overactive, possibly influencing tear film retention.

The pallidopyramidal syndromes: nosology, aetiology and pathogenesis.

PURPOSE OF REVIEW: The aims of this review is to suggest a new nomenclature and classification system for the diseases currently categorized as neurodegeneration with brain iron accumulation (NBIA) or dystonia-parkinsonism, and to discuss the mechanisms implicated in the pathogenesis of these diseases. RECENT FINDINGS: NBIA is a disease category encompassing syndromes with iron accumulation and prominent dystonia-parkinsonism. However, as there are many diseases with similar clinical presentations but without iron accumulation and/or known genetic cause, the current classification system and nomenclature remain confusing. The pathogenetic mechanisms of these diseases and the causes of gross iron accumulation and significant burden of neuroaxonal spheroids are also elusive. Recent genetic and functional studies have identified surprising links between NBIA, Parkinson's disease and lysosomal storage disorders (LSD) with the common theme being a combined lysosomal-mitochondrial dysfunction. We hypothesize that mitochondria and lysosomes form a functional continuum with a predominance of mitochondrial and lysosomal pathways in NBIA and LSD, respectively, and with Parkinson's disease representing an intermediate form of disease. SUMMARY: During the past 18 months, important advances have been made towards understanding the genetic and pathological underpinnings of the pallidopyramidal syndromes with important implications for clinical practice and future treatment developments.

Phenotypic overlap in familial and sporadic primary adult-onset extracranial dystonia.

We recently demonstrated that familial and sporadic blepharospasms share several phenotypic features (including age of dystonia onset, sex, and tendency to spread) believed to reflect the etiology of a blepharospasm. To investigate whether familial and sporadic forms of primary adult-onset dystonia other than the blepharospasm also share phenotypic features, we studied the families of 98 probands with primary adult-onset dystonia other than blepharospasms using a validated two-step procedure (questionnaire and clinical examination) that yields 95 % sensitivity and 100 % specificity when used to identify dystonia among relatives. The 98 probands provided a population of 402 living first-degree relatives aged 20 years or more, 336 of whom (83 %, 111 parents, 152 siblings, and 73 children) were screened for dystonia. The screening procedure identified 26 affected relatives (five parents, 16 siblings, and five children; 11 men/15 women; age at dystonia onset, 51 ± 11.7 years) from 24/98 families (25 %). No causes of secondary dystonia were found in the relatives who suffered from various forms of dystonia. When familial and sporadic patients were compared, no significant differences emerged in age, education, family size, sex distribution, age at dystonia onset, or tendency to spread. The phenotypic overlap we observed between the study groups suggests that familial and sporadic patients with primary adult-onset dystonia other than blepharospasm probably share a common etiological background.

The blink reflex recovery cycle differs between essential and presumed psychogenic blepharospasm.

BACKGROUND: Psychogenic blepharospasm is difficult to distinguish clinically from benign essential blepharospasm (BEB). The blink reflex recovery cycle measures the excitability of human brainstem interneurons and is abnormal in BEB. We wished to study the blink reflex recovery cycle in patients with atypical (presumed psychogenic) blepharospasm (AB). METHODS: This was a prospective data collection study investigating the R2 blink reflex recovery cycle at interstimulus intervals (ISI) of 200, 300, 500, 1,000, and 3,000 msec in 10 patients with BEB, 9 patients with AB, and 9 healthy controls. All patients had spasm of the orbicularis oculi muscles. To compare individual patients, an R2 recovery index was calculated as average of the recovery values at ISIs of 200, 300, and 500 msec, with the upper limit of normal defined as mean (control group) + 2 SD. RESULTS: The R2 recovery cycle was significantly disinhibited in patients with BEB, whereas patients with AB did not differ from controls on a group level. The upper limit of normal for the R2 recovery index was 61%. The R2 index was abnormal in 9 out of 10 patients with BEB and in none of the patients with AB. CONCLUSIONS: A normal blink reflex recovery cycle indicates normal brainstem interneuron excitability. Assessment of the R2 recovery cycle may provide a useful diagnostic tool to distinguish patients with psychogenic blepharospasm from BEB and is worthy of further study.

The blepharospasm disability scale: an instrument for the assessment of functional health in blepharospasm.

Assessment of the functional status in patients with blepharospasm is of major importance for clinical practice and outcome studies. The Blepharospasm Disability Scale (BDS) is specifically directed to measure the disability in these patients. The metric properties of this instrument were evaluated. Reliability, validity, and responsiveness to within-patient health changes over time of the BDS were assessed in 40 patients with essential blepharospasm treated with botulinum toxin injections. The reliability of the scale was sufficient for use on group level (Cronbach's alpha coefficient, 0.69). Evidence of discriminant validity was provided by the difference in median score on the BDS between 21 newly admitted patients and 19 patients already under treatment (p < 0.001). Convergent validity was supported by correlations between BDS and neurological impairment scores (range, Spearman correlation coefficients, 0.65-0.79). Responsiveness to health changes was demonstrated by a significant difference between median BDS scores before treatment and 2 weeks after treatment with botulinum toxin (p < 0.01). The BDS is a useful disease-specific instrument to assess disability. Completion of the questionnaire is easy and takes only a few minutes. The instrument is suitable for use in patient care, descriptive outcome studies, and should be considered in controlled clinical trials.

Prevalence of focal dystonias in the western area of Tottori Prefecture in Japan.

We evaluated the prevalence of focal dystonias in the western area of Tottori Prefecture in Japan. The population of the area was 244,935 on October 1, 1992. Because four patients with blepharospasm and three patients with writer's cramp did not visit any hospitals or clinics in 1993 and did not reply to our question letter, we could not confirm their present condition: with or without focal dystonia in 1993. Four patients with facial dystonia including blepharospasm and oromandibular dystonia, seven with spasmodic torticollis, and four with writer's cramp were observed. The prevalence of focal dystonias was 6.12 per 100,000 persons, which may be lower than that in western countries. Although the reasons for this difference are still unclear, a genetic factor may be one implication.

Reliability among neurologists in the severity assessment of blepharospasm and oromandibular dystonia: a multicenter study.

The reliability of a scale of 0 to 4 (where 0 is normal) in rating the severity of blepharospasm (BS) and oromandibular dystonia (OMD) was evaluated by the concordance among six neurologists from different neurological institutions. As expressed by k index, interobserver agreement was moderate either for BS or for OMD according to the Landis classification. Neurologists showed different rating attitude toward BS and OMD. In fact, the category analysis showed that raters were inclined to overestimate BS and to underestimate OMD. The familiarity with dystonia influenced reliability more than the length of professional experience in neurology. In fact, when examiners were subdivided into subgroups (each of three raters) according to the former criteria, the level of interobserver agreement increased significantly. Almost perfect agreement was obtained in intrarater comparisons. These results may be of value with regard to the conduct of multicenter epidemiologic and clinical studies on focal dystonias.

Signs of essential blepharospasm: a motion-picture analysis.

Motion pictures of 15 patients with essential blepharospasm were studied. Previously unrecognized signs indicated multiple cranial nerve involvement. These signs include impersistence of gaze, lid retraction, tongue thrust, head tilts, head jerks, vertical gaze spasms, and asymmetry. The sugns were also observed in a patient with bilateral blepharospasm who had a history of Bell's palsy suggesting facial nerve injury as a possible factor in blepharospasm. The presence of these signs can be explained by known neural pathways, but the site, or sites, of the lesion remains obscure. These signs may be important in assessing severity and in treatment evaluation.