Facial Nerve Center Research

The Facial Nerve Center at Massachusetts Eye and Ear is involved in all aspects of research regarding facial paralysis. Our projects range from clinical research studies, which look at the effectiveness of certain kinds of therapy, through basic science projects which examine nerve regeneration in laboratory models. Research is an ever-changing and evolving aspect of what we do at the Infirmary, and we are constantly adding to our research repertoire. Our current research thrusts are listed below. For more information on any of the projects, click on their titles.

Clinical Research

Three Dimensional Dynamic Analysis of Facial Movements

Despite the significant impact that facial paralysis has on quality of life and daily function, there is no reliable, accepted method to quantitatively measure facial movement or synkinesis. To address this problem, we are currently developing a novel three-dimensional video system capable of quantifying disordered facial movement. This objective data will help guide therapeutic decision-making prior to intervention and enable healthcare providers to better assess the efficacy of the varied treatment modalities for facial nerve disorders.

Future research with this technology will be aimed at developing specialized software for the automated tracking of selected facial features, and quantifying incorrect regeneration, also termed synkinesis. Refinement of a 3-D dynamic imaging system will give us a powerful tool to quantitatively assess a patient’s facial function regardless of the severity, cause, or treatment status of the disorder.

Clinical Approaches & Outcomes in Facial Paralysis Management

Our focus here is to examine our everyday clinical approaches to patients with facial nerve disorders, and scrutinize whether interventions actually translate into better facial function and improved quality of life.


With the goal of continuous improvement of the care of our facial nerve patients, we are currently examining the efficacy of a variety of our clinical approaches. Using several validated surveys to assess facial function, we are scrutinizing the translation of interventions into improved facial function and quality of life. Administered by the clinicians, the Facial Grading Scale and the Synkinesis Questionnaire assesses the decreasing amounts of aberrant movement in a patient’s face after receiving physical therapy and botulinum toxin treatment, respectively. The FACE Instrument, completed by the patient, measures quality of life with respect to the face, and can be applied to all of our treatment options. By measuring how each treatment improves specific conditions, we can continue to improve patient care offered at the Facial Nerve Center.

Endoscopic Nerve Harvest

One important way that we can improve the quality of life of our patients is to limit post-operative discomfort and scarring. Therefore, we are constantly searching for new operative techniques and technology to aid us in restoring facial function. Thus, we recently began to employ an endoscopic nerve harvest technique similar to the technique used in cardiac surgery to harvest veins through minimally invasive techniques. In our patients, the endoscopic method improves operative times and minimizes scarring. By applying newly available medical innovations like these, our patients will continue to receive the best care possible.

Basic Science

Surgical Management of Facial Nerve Injury

This project involves rat facial nerve manipulation (cut, crush, or conduit repair), followed by quantitative measurement of recovery of facial function from videographic and electronic recordings. It also includes observations of facial nerve regeneration in mice whose motor axons constitutively express yellow fluorescent proteins, to understand the anatomic correlates of synkinesis.

We are using highly sensitive electronic recordings to give precise facial movement data in these animals. To date, our work has yielded insight into the normal rodent facial function, and has given information regarding the rate and degree of recovery after nerve injury and repair. In the future, we will test potential treatments using this model, and hope to contribute to discoveries of new and better ways to treat our patients who suffer from facial nerve disorders

Advanced Neural Conduit Repair

This study involves the implantation of tubular conduits across rat sciatic nerve defects, and the measurement of recovery via quantitative histologic and functional parameters. Conduits contain Schwann cells, neural stem cells, and other cell types, gels, and substances likely to enhance the regeneration process.

Bionic Facial Pacing

We are excited about recent breakthrough technology developed for bionic control of limb prostheses, because we believe it could be applied to facial movement disorders. By implanting myoelectric sensors and stimulating electrodes into the facial musculature, our goal is to drive movements to paralyzed facial zones. The Facial Nerve Center is currently designing experiments to study the feasibility of such a device.

Our Articles

View a complete list of publications on pubmed.gov.

For full-text downloadable PDF files of our research, please see the select list of links below:

Multimodality Approach to Management of the Paralyzed Face
Tessa A. Hadlock, M.D., Mack L. Cheney, M.D

Facial Reanimation Surgery
Tessa A. Hadlock M.D., Mack L. CheneyM.D., and Michael J. McKenna M.D.

Botulinum Toxin and Quality of Life in Patients With Facial Paralysis

Tessa A. Hadlock, M.D.

Early Temporalis Muscle Transposition for the Management of Facial Paralysis

Mack L. Cheney, M.D. and Michael J. McKenna, M.D.

A New Artificial Nerve Graft Containing Rolled Schwann Cell Monolayers

Tessa A. Hadlock, M.D., Mack L. Cheney, M.D.

A Tissue-Engineered Conduit for Peripheral Nerve Repair

Tessa A. Hadlock, M.D., Mack L. Cheney, M.D

Baiting the Cross-Face Nerve Graft With Temporary Hypoglossal Hookup

Tessa A. Hadlock, M.D., Mack L. Cheney, M.D

Quantification of Functional Recovery Following Rat Sciatic Nerve Transection

Tessa A. Hadlock, M.D.

Validation of the Synkinesis Assessment Questionnaire

Mara Wernick Robinson, P.T., M.S., N.C.S., Tessa A. Hadlock, M.D.