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Objective: To design and validate a clinical diagnostic guideline for aiding physicians in confirming or refuting suspected blepharospasm., Methods: The guideline was developed and validated in a 3-step procedure: 1) identification of clinical items related to the phenomenology of blepharospasm, 2) assessment of the relevance of each item to the diagnosis of blepharospasm, and 3) evaluation of the reliability and diagnostic sensitivity/specificity of the selected clinical items., Results: Of 19 clinical items initially identified, 7 were admitted by content validity analysis to further assessment. Both neurologists and ophthalmologists achieved satisfactory interobserver agreement for all 7 items, including "involuntary eyelid narrowing/closure due to orbicularis oculi spasms," "bilateral spasms," "synchronous spasms," "stereotyped spasm pattern," "sensory trick," "inability to voluntarily suppress the spasms," and "blink count at rest." Each selected item yielded unsatisfactory accuracy in discriminating patients with blepharospasm from healthy subjects and patients with other eyelid disturbances. Combining the selected items, however, improved diagnostic sensitivity/specificity. The best combination, yielding 93% sensitivity and 90% specificity, was an algorithm starting with the item "stereotyped, bilateral, and synchronous orbicularis oculi spasms inducing eyelid narrowing/closure" and followed by recognition of "sensory trick" or, alternatively, "increased blinking.", Conclusion: This study provides an accurate and valid clinical guideline for diagnosing blepharospasm. Use of this guideline would make it easier for providers to recognize dystonia in clinical and research settings.

Objective: The aim of this study was to investigate whether increased blink rate (BR) is part of the clinical spectrum of primary blepharospasm (BSP)., Methods: We enrolled 40 patients (16 patients with an increased BR but without typical orbicularis oculi [OO] spasms, and 24 patients with typical involuntary OO spasms) and 18 healthy subjects. The BR, blink reflex recovery cycle, and somatosensory temporal discrimination threshold (STDT) were tested in patients and controls., Results: Patients who had typical OO spasms had an altered R2 recovery cycle whereas those who had an increased BR alone had a normal blink reflex recovery cycle. STDT values were higher in patients than in healthy subjects and no difference was found in the STDT abnormalities in the 2 groups of patients., Conclusions: Our study shows that, despite the similar STDT abnormalities, the different changes in the R2 recovery cycle in patients with BSP and those with increased BR alone suggest that these disorders arise from different pathologic mechanisms.

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.

Background: Traditionally, benign essential blepharospasm (BEB) is considered a disorder caused by basal ganglia dysfunction. Electrophysiologic and brain imaging studies suggest pathologic changes in excitability in the primary motor cortex (MC), anterior cingulate (AC), and secondary motor areas, such as premotor (PMC) and supplementary motor cortices (SMA)., Methods: In this pilot study of 7 patients with BEB, we experimentally reduced cortical excitability of 4 areas: MC (first dorsal interosseus area), PMC, SMA, and AC, each with 3 noninvasive techniques: low-frequency repetitive transcranial magnetic stimulation (lfrTMS), continuous theta burst stimulation (cTBS), and cathodal transcranial direct current stimulation (tDCS). Primary outcome was the clinical effects on blepharospasm (blink rate observation by an investigator blinded to the intervention and subjective rating by the patient); secondary outcome was the blink reflex recovery curve (BRR)., Results: lfrTMS resulted in a significant improvement over all 4 brain areas for physician rating, patient rating, and BRR, whereas cTBS and tDCS showed only trends for improvement in physician rating, but no improvements for patient rating and BRR. lfrTMS had a significantly higher effect over AC than MC for physician rating, but no differences were seen for other pairwise comparisons of stimulated brain areas., Conclusions: Electrophysiologic and clinical improvements by functional inhibition of the medial frontal areas using low-frequency repetitive transcranial magnetic stimulation suggests that hypersensitivity of the anterior cingulate is directly or indirectly involved in the pathophysiology of benign essential blepharospasm. Inhibition of these areas using low-frequency repetitive transcranial magnetic stimulation could provide a therapeutic tool and is worthy of a larger study.

Background: Persistent, frequent, nonepileptic paroxysmal eyelid movements were observed in 19 children and adults with well-controlled generalized epilepsy., Methods: Patients were identified from five epilepsy centers., Results: Seventeen patients were female and two male. All had generalized photosensitive epilepsy requiring antiepileptic drugs (AEDs). In two children, paroxysmal eyelid movements began 2 to 4 years before their epilepsy was noted; in the remainder, it was noted when epilepsy was first diagnosed. Age at last follow-up was 8 to 38 years (average 21 years) with average follow-up of 9 years. All patients showed photosensitive generalized spike-wave discharges on EEG. Paroxysmal eyelid movements were a source of diagnostic confusion, but direct examination and video during EEG recording distinguished the attacks from absence seizures. In all cases, the epilepsy is completely or nearly completely controlled with AEDs, but the paroxysmal eyelid movements have not resolved with age. In 12 cases, there was a family history of the eyelid disorder without epilepsy. Videos of patients and an affected parent are available on the Neurology Web site., Conclusion: There is an association between paroxysmal eyelid movements and photosensitive generalized epilepsy, creating diagnostic confusion.

Objective: To investigate brain areas involved in the initiation and execution of eyelid spasm in patients with benign essential blepharospasm., Methods: The authors used fMRI and correlated the blood oxygenation level-dependent (BOLD) signal with epochs of frequent eyelid spasm in six patients and with epochs of voluntary eye blinks in four healthy subjects., Results: Spasm epochs were accompanied by activation in a subregion of the putamen in all patients, whereas voluntary blinking in healthy subjects was not. Other areas of activation common to patients and healthy subjects included frontal and parietal operculum, supplementary motor area, primary sensorimotor cortex, various visual areas, and the cerebellum., Conclusions: The striatum may be involved in the initiation or execution of eyelid spasm. Future studies, possibly including electromyography (EMG) during fMRI, are needed to detect the sequence and role of other concomitantly activated areas.

Benign essential blepharospasm is a common focal dystonia characterized by involuntary eyelid closure. Its etiology, supported by animal models, appears to be multifactorial, representing the influence of a genetic background and an environmental trigger. The genetic background could be responsible for the reduced brain inhibition, identified with physiologic studies that would set up a permissive condition for increased brain plasticity. Reduced D2 receptors identified with PET might be an indicator of this reduced inhibition. The trigger could be repetitive use or local ocular disease. Although symptomatic therapy is available, better approaches are needed and will likely become available as the genetics and pathophysiology become well understood.

Background: Apraxia of lid opening (ALO) is a nonparalytic inability to open the eyes at will in the absence of visible contraction of the orbicularis oculi (OOc) muscle., Objective: To test the hypothesis that sustained activity of the OOc is a major factor in the difficulty in opening the eyes in this condition., Methods: Lid movement detected in an electromagnetic field and electromyogram activity of the septal and pretarsal portions of the OOc were recorded in 12 healthy control subjects and 12 patients with a clinical diagnosis of ALO. The latencies to onset and to complete eye opening and the time during which eye opening was sustained were measured and analyzed in relation to OOc activity., Results: The lid opening latencies and the lid movement duration were significantly increased in patients compared with control values. An abnormal persistence of OOc activity was present in 10 of the 11 patients with a delay in complete lid opening. The complete lid opening delay showed a strong positive correlation with the time it took to inhibit the OOc activity. This relationship fit the same linear regression in both groups., Conclusions: Patients with ALO show significant delays in eye opening. An abnormal persistence of OOc activity, detectable electromyographically but not clinically, could be the main factor contributing to the delay in lid opening in these patients.

Single-volume proton magnetic resonance spectroscopy, localized to basal ganglia, was carried out in 10 patients with primary blepharospasm (PB) to assess the levels of N-acetyl aspartate (NAA), creatine-phosphocreatine, and choline-containing compounds. NAA was reduced significantly in patients compared with control subjects. This result suggests a striatal neuronal loss in PB.