What Happens in the Other Eye? Blink Reflex Alterations in Contralateral Side After Facial Palsy

Abstract

Alterations in blink reflex excitability may occur in the contralateral side (CLS) and in the symptomatic side after peripheral facial palsy (PFP). In this study, the alterations of blink reflex in CLS were evaluated in cases with PFP who showed "three different types" of recovery. For this purpose, the R2 response area and recovery curve of the blink reflex were evaluated. The study included 51 patients suffering from PFP and 20 age- and sex-matched healthy controls. Cases with PFP were divided into three groups: patients with PFP with partially cured and accompanied by synkinesis (postfacial syndrome), patients with PFP with residual weakness, and patients who suffered from recurrent PFP. All three groups' R2 values of CLS were compared with the values of controls and patients who had synkinesis. The CLS of all three groups' R2 area values were found to be significantly higher when compared with controls. These values were found to be highest in patients who suffered from recurrent PFP. Hyperexcitability occurs in CLS after PFP and this is highest in patients who suffer from recurrent PFP. It suggested that the contralateral reorganization caused by peripheral nerve damage correlates with the severity of the lesion and the recurrence of axon damage enhances the excitability of the reflex cycle, which affects the contralateral facial nucleus.

DeepSmile: Anomaly Detection Software for Facial Movement Assessment

“…However, the model also computed a smaller degree of anomaly on the healthy side of the face. This reflects the phenomenon of compensation of the non-paralyzed side that we observe in clinical practice, but underlines the fact that, depending on the case, this side cannot really be considered as healthy, at least from the point of view of movement ( [62,63]). This data objectively underlines the fact that the management of patients with facial paralysis concerns the whole face.…”

Long‐Term Effect of Prednisolone on Functional Blink Recovery after Transient Peripheral Facial Motor Paralysis

“…11 In addition, the sum of the integrated OO-EMG for both eyelids at each time point for all types of blinks was approximately constant during the study, indicating a central control mechanism for the EMG activity of both eyelids. 12 The effect of prednisolone administration did not immediately interfere with the OO-EMG and the blink kinematics of the palsied eyelid because no differences in the functional blink recovery were seen between the patient groups in the first 20 weeks after the start of the palsy. After 20 weeks, the maximal down-phase amplitude in the prednisolone patient's recordings was significantly larger when compared with the nonmedicated patient's.…”

“…This finding can be attributed to the nonmodulation effect of the EMG, in which a minimally amplified EMG captures the synchronous volley of the reflex amplitude, for example, the start time and not the gain setting 11 . In addition, the sum of the integrated OO‐EMG for both eyelids at each time point for all types of blinks was approximately constant during the study, indicating a central control mechanism for the EMG activity of both eyelids 12 …”

“…11 In addition, the sum of the integrated OO-EMG for both eyelids at each time point for all types of blinks was approximately constant during the study, indicating a central control mechanism for the EMG activity of both eyelids. 12…”

Recent progress in facial paralysis: advances and obstacles

“…Sahin et al [34] reported on their study examining the blink reflex on the contralateral side of 51 patients with peripheral facial paralysis comprising three groups: those with partial improvement and synkinesis, those with persistent weakness, and those with recurrence of facial paralysis. The study used R2, the reflex response following initial motor action potential, and found reflex responses in the contralateral side to be significantly increased when compared with controls, and highest in patients with recurrent paralysis.…”