Pilot Study: Use of the Saccadometer to Detect Characteristic Saccadic Peak Velocity in Myasthenia Gravis Patients

Fast eye movements have been shown to demonstrate characteristics that are specific to myasthenia gravis that are not present in other eye movement disorders. It is possible to measure these eye movements and potentially identify these characteristics using new portable eye movement testing equipment. The aim of this pilot study is to discover if these characteristics can be identified using portable eye movement testing equipment in patients with a confirmed diagnosis of myasthenia gravis.

Study Overview

• Status: Completed
• Conditions: Myasthenia Gravis
• Intervention / Treatment: Device: Quantitative measurement of eye movements

Detailed Description

The diagnosis of Myasthenia Gravis (MG) can be challenging, particularly in its ocular manifestation with current clinical procedures. Previous research has shown that fast eye movements in patients suffering with MG have quite specific characteristics that can be used to correctly diagnose the condition. The Saccadometer is a portable eye movement testing device that may provide the ability to detect the characteristics of fast eye movements that Myasthenia patients alone demonstrate - specifically these are hyperfast movements that are present when slower eye movements are impaired by the disease process. These fast movement characteristics are not present in defects of eye movements due to other aetiologies.

Saccadic properties of a small group of patients with a confirmed diagnosis of MG will be measured to identify if characteristic hyperfast saccades are present.

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: Yes

Description

Inclusion Criteria:

Patient participants

• Confirmed diagnosis of Myasthenia Gravis by either a positive acetylcholine antibody serum test (AChR) and/or a positive single fibre electromyograph (SFEMG) test.
• Patient participants must have also had at least one episode of diplopia and/or eye movement abnormality attributed to their diagnosis of MG.

Healthy participants:

• Must have no history of eye movement abnormality
• No have no history of other auto-immune disease (specifically diabetes, Thyroid Eye Disease and Chronic External Ophthalmoplegia).

Exclusion Criteria:

• Patients without confirmed Myasthenia Gravis diagnosis by means of either a positive AChR serum test and/or a positive SFEMG test.
• Patients with confirmed Myasthenia Gravis who have not had at least one episode of diplopia and or ptosis.
• Patients with current or previous episodes of ocular motility dysfunction that have a confirmed diagnosis other than Myasthenia Gravis.
• Any healthy participant found to have an abnormality of vision or eye movement upon screening or a history of auto-immune disease.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Health Services Research
• Allocation: N/A
• Interventional Model: Single Group Assignment
• Masking: None (Open Label)

Number of Arms

1

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Other: Myasthenia Gravis; Participants with a confirmed diagnosis of Myasthenia Gravis	Device: Quantitative measurement of eye movements; Saccadometer © - diagnostic device: non-invasive quantitative assessment of eye movement

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Saccadic Peak Velocity	Participants will be recruited, consented and tested at a single visit during their routine clinical visit, up to one year after being recruited. Quantitative assessment of their eye movements using the Saccadometer will be assessed at that point of contact and the outcome measure recorded.	Measured at first and only contact point within study i.e. day one and then not tested again

Collaborators and Investigators

• Sponsor: University of Liverpool
• Collaborators: Liverpool University Hospitals NHS Foundation Trust
• Investigators: Principal Investigator: Craig Murray, MRes, University of Liverpool

Study record dates

Study Major Dates

• Study Start (Actual): March 1, 2016
• Primary Completion (Actual): March 1, 2018
• Study Completion (Actual): March 1, 2018

Study Registration Dates

• First Submitted: February 26, 2016
• First Submitted That Met QC Criteria: July 9, 2024
• First Posted (Actual): July 15, 2024

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: December 13, 2024
• Last Verified: July 1, 2024

More Information

Terms related to this study

• Keywords: Saccades
• Additional Relevant MeSH Terms: Neurologic Manifestations; Musculoskeletal Diseases; Nervous System Diseases; Muscular Diseases; Neuromuscular Manifestations; Pathologic Processes; Neoplasms by Site; Neoplasms; Neuromuscular Diseases; Autoimmune Diseases; Immune System Diseases; Autoimmune Diseases of the Nervous System; Neurodegenerative Diseases; Paraneoplastic Syndromes, Nervous System; Nervous System Neoplasms; Paraneoplastic Syndromes; Neuromuscular Junction Diseases; Muscle Weakness; Myasthenia Gravis
• Other Study ID Numbers: UoL001162

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No