What is the Sunnybrook Score? How is Facial Paralysis Measured?

Facial paralysis is not only an aesthetic issue; it is a complex neurological condition that can affect many important functions ranging from facial expressions to speech, from eye closure to daily quality of life. Therefore, accurately analyzing the severity of facial paralysis is crucial for the success of treatment methods. But how do doctors measure how well facial muscles are functioning, which areas have weakness, or the level of involuntary muscle movements? Have you ever wondered? If your answer is “yes,” you can explore our article titled “What is the Sunnybrook Score? How is Facial Paralysis Measured?” We wish you healthy days and enjoyable reading.

What is the Sunnybrook Score?

The Sunnybrook Score is an advanced clinical grading system used to evaluate facial muscle function in patients with facial paralysis in detail. Also known as the “Sunnybrook Facial Grading System,” this method aims to measure the severity of facial paralysis more objectively by analyzing facial symmetry at rest, voluntary facial movements, and involuntary movements known as synkinesis.

During this assessment, different facial movements such as eyebrow raising, eye closure, smiling, lip movement, and corner-of-mouth control are evaluated. In addition, synkinesis findings frequently seen after facial paralysis—such as mouth movement while blinking or involuntary neck muscle contraction while smiling—are also included in the scoring. Thus, the Sunnybrook Score is considered one of the most commonly used evaluation systems in modern facial paralysis assessment.

How is the Sunnybrook Score Calculated?

The Sunnybrook Score is calculated through a detailed scoring system designed to objectively evaluate facial muscle function in patients with facial paralysis. In this system, facial symmetry at rest, voluntary facial movements, and involuntary movements known as synkinesis are assessed separately to generate a total score.

During evaluation, facial actions such as eyebrow raising, eye closure, smiling, lip movement, and corner-of-mouth control are analyzed. In addition, synkinesis findings commonly seen after facial paralysis—such as mouth movement during blinking or involuntary neck muscle contraction while smiling—are also included in the scoring. Based on the total score obtained, the severity of facial paralysis can be analyzed in greater detail, allowing a more controlled treatment planning process.

Which Actions are Analyzed in the Sunnybrook Score?

Many parameters are analyzed in the Sunnybrook Score. These include the following:

• Eyebrow Raising is Evaluated: The ability of the patient to actively use the forehead muscles is assessed. Symmetry of eyebrow elevation is examined.
• Eye Closure Strength is Measured: The ability to fully and strongly close the eyes is analyzed. Incomplete eye closure, which is common in facial paralysis, is an important factor in evaluation.
• Smile Movement is Assessed: Symmetry of the mouth corners and coordination of facial muscles during smiling are evaluated. Asymmetry or deviation caused by facial paralysis is analyzed.
• Lip Movements are Evaluated: Lip range of motion, control, and symmetry are examined. Muscle activity during speech and facial expressions is observed.
• Mouth Corner Control is Analyzed: The balance of the mouth corners at rest and during movement is assessed.
• Facial Symmetry at Rest is Examined: Facial asymmetry when the patient is not making any expressions is evaluated. Eyelids, cheeks, and mouth region are carefully analyzed.
• Voluntary Facial Movements are Measured: The strength and coordination of intentional facial expressions are assessed.
• Synkinesis Findings are Evaluated: Involuntary muscle movements are analyzed. For example, mouth movement while blinking or neck muscle contraction while smiling is included in scoring.
• Nasal Region Muscle Activity is Examined: Muscle activity around the nose and midface is evaluated to analyze overall facial coordination.
• Neck Muscle Activity is Observed: Involuntary contractions, especially in the platysma muscle, are assessed in terms of synkinesis.
• Quality of Facial Movements is Analyzed: Not only the presence of movement but also how natural, controlled, and symmetrical it is is evaluated.
• Strength and Control of Muscle Movements is Measured: Whether muscles function weakly, moderately, or strongly is assessed to better determine the severity of facial paralysis.

The Difference Between Sunnybrook Score and House-Brackmann Score

Although Sunnybrook Score and House-Brackmann Score are sometimes thought to be the same system, they are actually different grading methods. The differences include:

• The Sunnybrook system provides a more detailed analysis, while the House-Brackmann system offers a more general classification.
• Sunnybrook evaluates different facial regions separately, whereas House-Brackmann evaluates the face as a whole.
• Synkinesis (involuntary movements) is assessed in detail in Sunnybrook, while it is more limited in House-Brackmann.
• Sunnybrook provides more detailed facial symmetry analysis, while House-Brackmann is more basic.
• Sunnybrook is more sensitive for tracking small changes during treatment, while House-Brackmann is used for broader staging.
• Sunnybrook analyzes specific facial expressions such as eyebrow raising, eye closure, and smiling separately, while House-Brackmann focuses on overall facial movement.
• Sunnybrook is scored out of 100 points, while House-Brackmann typically uses a 1–6 grading system.
• In Sunnybrook, higher scores indicate better facial function, while in House-Brackmann lower grades indicate better function.
• Sunnybrook provides more detailed data for rehabilitation and botulinum toxin planning, while House-Brackmann is mainly used for clinical classification.
• Sunnybrook evaluates both voluntary and involuntary movements together, whereas House-Brackmann focuses more on overall paralysis severity.
• Sunnybrook is considered a more comprehensive modern assessment tool, while House-Brackmann is simpler and faster to use.

In Which Patients is the Sunnybrook Score Used?

Although the Sunnybrook Score is generally used in patients with facial paralysis, it is not applied to every case. The relevant patient groups include:

• Patients with Bell’s palsy
• Individuals with traumatic facial paralysis
• Patients with Ramsay Hunt syndrome
• Individuals who have undergone facial nerve surgery
• Patients with advanced facial paralysis and synkinesis
• Chronic facial paralysis cases
• Congenital facial paralysis cases
• Tumor-related facial paralysis cases
• Patients undergoing facial reanimation procedures
• Patients planned for botulinum toxin treatment
• Patients receiving physical therapy and facial rehabilitation
• Individuals with partial or complete facial paralysis
• Pediatric patients
• Patients planned for revision or additional treatment

Is the Sunnybrook Score Enough on Its Own?

Although the Sunnybrook Score is a highly detailed and widely used measurement system in facial paralysis assessment, it is often not sufficient on its own. Facial paralysis is a multifactorial condition that includes not only loss of muscle movement but also nerve damage severity, daily functional limitations, eye protection issues, speech difficulties, aesthetic concerns, and psychological effects. Therefore, while the Sunnybrook system provides valuable clinical data by analyzing facial symmetry, voluntary movements, and involuntary synkinesis in detail, it is usually interpreted alongside physical examination, patient history, and additional diagnostic tools.

Methods such as EMG (electromyography), video analysis, nerve conduction studies, and functional facial assessments help provide a more comprehensive understanding of nerve damage. In addition, factors such as aesthetic expectations, eye closure function, speech quality, and synkinesis severity are all considered in treatment planning. As a result, while the Sunnybrook Score is a valuable tool in modern facial paralysis evaluation, the most accurate outcomes are achieved through a multidisciplinary and comprehensive clinical approach.

What Does Improvement in the Sunnybrook Score Mean?

An improvement in the Sunnybrook Score indicates that facial muscle function in a patient with facial paralysis is recovering and that symmetry and control of facial movements are improving. This improvement may reflect stronger and more coordinated voluntary movements such as eyebrow raising, eye closure, smiling, lip movement, and mouth corner control. At the same time, a reduction in facial asymmetry at rest and better control of synkinesis (involuntary movements) are also important contributors to an increased score.

In addition, a decrease in synkinesis findings—such as mouth movement during blinking or involuntary neck muscle contraction while smiling—may indicate healthier nerve recovery. However, the degree of improvement varies from patient to patient, as factors such as the cause of facial paralysis, severity of nerve damage, timing of treatment, and individual healing capacity all play important roles. Overall, an increase in the Sunnybrook Score is generally considered a positive sign of improved, more natural, balanced, and controlled facial function.

If you would like to learn more about the Sunnybrook Score and receive high-quality treatment, you may schedule a consultation with Dr. Berke Özücer; this can help you achieve excellent outcomes in facial paralysis treatment.