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

Not Applicable

Completed

• Conditions: Myasthenia Gravis
• Interventions: Device: Quantitative measurement of eye movements

• Registration Number: NCT06501794
• Lead Sponsor: University of Liverpool

Brief Summary

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.

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 Timeline

• Study First Submitted: 2016-02-26
• Study Start: 2016-03
• Primary Completion: 2018-03
• Study Completion: 2018-03
• Status Verified: 2024-07
• Study First Submitted QC: 2024-07-09
• Study First Posted: 2024-07-15
• Last Update Submitted: 2024-12-13
• Last Update Posted: 2024-12-18

Recruitment & Eligibility

• Status: COMPLETED
• Sex: All
• Target Recruitment: 20

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 & Design

• Study Type: INTERVENTIONAL
• Study Design: SINGLE_GROUP

Arm && Interventions

Group	Intervention	Description
Myasthenia Gravis	Quantitative measurement of eye movements	Participants with a confirmed diagnosis of Myasthenia Gravis

Primary Outcome Measures

Name	Time	Method
Saccadic Peak Velocity	Measured at first and only contact point within study i.e. day one and then not tested again	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.