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.

Download full-text PDF

Source
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3053342PMC
http://dx.doi.org/10.1212/WNL.0b013e31820c3074DOI Listing

Publication Analysis

Top Keywords

recovery cycle
28
blink reflex
20
reflex recovery
20
psychogenic blepharospasm
16
patients beb
12
beb patients
12
recovery
10
patients
10
presumed psychogenic
8
blepharospasm beb
8

Similar Publications

PIWI-interacting RNAs (piRNAs) are a class of small noncoding RNAs associated with PIWI proteins within the male germline, and they play significant roles in maintaining genome stability via the modulation of gene expression. The piRNAs are implicated in the progression of various cancers, but the simultaneous monitoring of multiple piRNAs remains a challenge. Herein, we construct a single-molecule biosensor based on polymerization-transcription-mediated target regeneration for the simultaneous one-pot detection of multiple piRNAs.

View Article and Find Full Text PDF

The products of an advanced sewage sludge fermentation process can be used to generate polyhydroxyalkanoates (PHAs), precursors of bioplastics considered excellent candidates for replacing petroleum-derived plastics. The aerobic feast-anoxic famine cycling strategy has proven to be an efficient method for enriching sewage sludge microbiota with PHA-producing microorganisms. This work evaluated the effect of different carbon to nitrogen ratios (C/N) of 3.

View Article and Find Full Text PDF

Groundwater plays a key role in the water cycle and is used to meet industrial, agricultural, and domestic water demands. High-resolution modeling of groundwater storage is often challenging due to the limitations of observation techniques and mathematical methods. In this study, two machine learning (ML) algorithms, namely random forest (RF) and artificial neural networks (ANNs), were employed to estimate groundwater level anomaly (GWLA) and groundwater storage anomaly (GWSA) with a 0.

View Article and Find Full Text PDF

This study investigates steam washing (SW) as an innovative pretreatment for municipal solid waste incineration fly ash (MSWI-FA) dechlorination, useful for a more effective stabilization in cementitious matrix. By using a detailed analytical approach (XRPD, XRF, ICP-MS, IRMS, SEM) and geochemical modeling, great focus is dedicated on pollutant leaching reduction and changes in ash physicochemical characteristics as a function of exposure time. The research demonstrates that SW removes up to 70 % cadmium, 17 % zinc, and 10 % lead, primarily by dissolving the soluble and carbonate/hydroxide fractions and promoting the reprecipitation and adsorption of heavy metals into more stable compounds.

View Article and Find Full Text PDF

We present direct differential phase recovery-an open-loop phasemeter topology for differential optical interferometric measurements. The technique aims to remove common mode signal dynamics prior to phase-tracking, which reduces the dynamic range requirements of the phasemeter tracking optical phase differences. A phase difference measurement is experimentally demonstrated with this technique, achieving a phase sensitivity of 1 × 10rad/Hz with a common-mode noise rejection of 141 dB.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!