Restoration of eye closure in facial paralysis using implantable electromagnetic actuator

Acceptance and willingness of patients with chronic facial nerve palsy for an implantable device that assists with eye closure

BACKGROUND

Patients with facial nerve palsy often experience lagophthalmos (incomplete eye closure), which can lead to exposure keratitis. The Bionic Lid Implant for Natural Eye Closure (BLINC) is a medical device designed to mimic the more natural blink kinetics than traditional lid loading techniques.

AIMS

This study aimed to evaluate potential factors that might influence the design of the BLINC device and willingness of participant to undergo the implant placement surgery.

METHODS

Patients attending a multidisciplinary facial nerve clinic were invited to complete a survey addressing patient acceptance of the BLINC device implantation.

RESULTS

Seventy-two patients were mailed the survey, of which 50 returned completed surveys (69%). The most important factor identified by participants was the device function (81% ranked as very important) and the least important factor was cost (16% ranked as very important). Median acceptable device function time was 5 years (range 1-10 years). Ten participants (20%) indicated willingness to be the first to trial BLINC. Women were more likely to rate visual appearance as important (OR 3.32, CI 1.14-9.62, p = 0.028), and less likely to rate user friendliness as important (OR 0.16, CI 0.04-0.52, p = 0.0021). Older participants were more likely to rate the length of recovery period as important (OR 1.04, CI 1.01-1.08, p = 0.006). Participants with complete eye closure were less likely to be willing to trial the implant (OR 0.08, CI 0.00-0.53, p = 0.006, whilst patients with eye irritation were more willing to trial the implant (OR 7.20, CI 1.12-142, p = 0.036).

CONCLUSION

Certain patient demographics impact patient aesthetic and functional preferences and the willingness to trial the BLINC device.

Dynamic eyelid reconstruction in facial nerve palsy

The consequences of facial nerve palsy and the secondary inability of eyelid closure and blink may lead to devastating complications for the patient, including blindness. Reconstruction techniques to improve eyelid position and function can be broadly classified into 'static' and 'dynamic' techniques. Generally, ophthalmologists have been familiar with static procedures such as upper eyelid loading, tarsorrhaphy, canthoplasty, and lower eyelid suspension. Recently, dynamic techniques are being increasingly described for patients who require definitive strategies to improve eyelid function, once the initial critical goals of corneal protection and vision preservation have been achieved. The choice of technique(s) is dependent upon the status of the main protractor of the eyelid region, as well as the age of the patient, the patient's morbidities and expectations, and surgeon preference. This review shall first describe the clinical and surgical anatomy relevant to the ophthalmic consequences of facial paralysis and discuss methods of defining function and outcomes. A comprehensive review of dynamic eyelid reconstruction is then presented with a discussion of the literature. These various techniques may not be familiar to all clinicians. It is important that ophthalmic surgeons are aware of all options available for their patients. Furthermore, eye care providers must have an understanding of when referral may be appropriate to provide timely intervention and optimal chances of recovery.

Development of an implantable bionic for dynamic eye closure in facial nerve paralysis: Evolution of the design

Facial nerve paralysis (FNP) presents with a constellation of clinical problems but its most concerning consequence is corneal exposure from lack of blinking. Bionic lid implant for natural closure (BLINC) is an implantable solution for dynamic eye closure in FNP. It uses an electromagnetic actuator to mobilise the dysfunctional eyelid by means of an eyelid sling. This study highlights issues relating to device biocompatibility and describes its evolution to overcome some of these issues. The essential components of the device are the actuator, the electronics including energy storage, and an induction link for wireless power transfer. Effective arrangement of these components within the anatomical confines and their integration is achieved through a series of prototypes. The response of each prototype is tested in a synthetic or cadaveric model for eye closure with the final prototype designed for acute and chronic animal trials.

The impact of radical parotidectomy with immediate facial nerve reconstruction: a quality-of-life measure

OBJECTIVE

Immediate facial nerve reconstruction is the standard of care following radical parotidectomy; however, quality of life comparisons with those undergoing limited superficial parotidectomy without facial nerve sacrifice is lacking.

METHOD

Patients who underwent parotidectomy were contacted to determine quality of life using the University of Washington Quality of Life and Parotidectomy Specific Quality of Life questionnaires. A total of 29 patients (15 in the radical parotidectomy and 14 in the limited superficial parotidectomy groups) completed and returned questionnaires.

RESULTS

Using the University of Washington Quality of Life Questionnaire, similar quality of life was noted in both groups, with the radical parotidectomy group having significantly worse speech and taste scores. Using the Parotidectomy Specific Quality of Life Questionnaire, the radical parotidectomy group reported significantly worse speech, eye symptoms and eating issues.

CONCLUSION

Those undergoing radical parotidectomy with reconstruction had comparable overall quality of life with the limited superficial parotidectomy group. The Parotidectomy Specific Quality of Life Questionnaire better identified subtle quality of life complaints. Eye and oral symptoms remain problematic, necessitating better rehabilitation and more focused reconstructive efforts.

Design of Soft Robotic Actuation for Supporting Eyelid Closure Movement

We have been developing a facial wearable robot to support the eyelid movements of patients with facial paralysis, especially on one side of the face [1]. This robot has a mechanism for supporting eyelid movements, made from a soft material, which is called the eyelid gating mechanism (ELGM). The ELGM deforms by simple rotational actuation inputs and its deformation is customized to the eyelid movements. Therefore, this robot can provide non-invasive and gentle support for eyelid movements. We herein describe the design rule of the ELGM, and based on this, we conducted a deformation analysis with a non-linear finite element method. We verified the deformation trend from the results, and developed three prototypes based on this trend. Using these prototypes, we conducted a clinical study with facial paralysis patients to evaluate if the ELGM is capable of assisting in closing the eyelid.

Facial Paralysis Discussion and Debate

This article examines 6 questions about facial paralysis answered by 3 experts in their field of facial plastic surgery. The topics covered include routine assessment, neuromuscular training, nonsurgical management, and the future of this field. All the authors answered these questions in a "How I do it" manner to provide the reader with a true understanding of their thoughts and techniques. This article provides a practical resource to all physicians and practitioners treating patients with facial paralysis on some of the most common questions and issues.