NCT06860360

Brief Summary

Rationale: Myasthenia Gravis (MG) is an autoimmune disorder (AID) with antibodies against the NMJ, resulting in various degrees of muscle fatigability and weakness. All striated muscles can be involved, although the extra-ocular muscles are most commonly affected, giving rise to a fluctuating ptosis and diplopia. Facial muscles are also commonly affected, resulting in eye closure weakness, difficulty chewing and swallowing or speech impairments. Antibodies against the acetylcholine receptor (AChR) are present in over 80% of generalized MG patients. In the pure ocular form, AChR antibodies are detectable in nearly 50% of all patients. In approximately 4%, antibodies against the postsynaptic muscle-specific receptor tyrosine kinase (MuSK) are found and in 15% of the patients with generalized disease, no serum antibodies are detected1-3. Approximately 15% of AChR MG patients has a thymoma, in which case the disease can be classified as a paraneoplastic syndrome2. With a prevalence of 1 to 2 per 10.000, MG is considered a rare disease2. The rarity of MG can make it difficult to diagnose, specifically for general Neurologists who are likely to encounter a patient with MG only a handful of times throughout their career. In addition, the fluctuating nature of the disease makes it difficult to make appropriate treatment decisions, especially as patients throughout the country are usually treated at one specialized center (in the Netherlands, the LUMC). Currently, patients who are in doubt whether they are experiencing an exacerbation have to make an appointment and travel for several hours to undergo assessment by their specialized Neurologist. An objective, reliable biomarker for disease severity that can be used at home would therefore greatly improve quality of life for many MG patients. Emerging possibilities in modern technologies can support doctors with all kinds of medical challenges, like offering diagnostic support, treatment decisions or patient follow-up. A technology of special interest for this study is advanced facial recognition. We aim to study the ability of existing software (FaceReader, Noldus) versus a deep learning model specifically developed for this purpose by the group of Jan van Gemert at the TU Delft to differentiate between healthy controls and patients with MG and between MG patients with different levels of disease severity. Primary objectives: To determine and compare the diagnostic yield of two different methods (FaceReader technology and a deep learning model specifically developed for video data) to analyse facial weakness from video recordings (04:00m) with different standardized facial expressions to:

  1. 1.Differentiate between MG patients and healthy controls.
  2. 2.Differentiate between mild and moderate to severe disease severity.

Trial Health

87
On Track

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Enrollment
90

participants targeted

Target at P50-P75 for all trials

Timeline
Completed

Started Dec 2020

Typical duration for all trials

Geographic Reach
1 country

1 active site

Status
completed

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

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Study Timeline

Key milestones and dates

Study Start

First participant enrolled

December 1, 2020

Completed
1.7 years until next milestone

First Submitted

Initial submission to the registry

August 3, 2022

Completed
5 months until next milestone

Primary Completion

Last participant's last visit for primary outcome

December 31, 2022

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

December 31, 2022

Completed
2.2 years until next milestone

First Posted

Study publicly available on registry

March 6, 2025

Completed
Last Updated

March 6, 2025

Status Verified

March 1, 2025

Enrollment Period

2.1 years

First QC Date

August 3, 2022

Last Update Submit

March 4, 2025

Conditions

Outcome Measures

Primary Outcomes (3)

  • FaceReader

    The primary parameter for the differentiation between healthy controls and MG and between different grades of MG disease severity with FaceReader is the diagnostic yield of individual muscles and combinations of muscles. The diagnostic yield is expressed as sensitivity, specificity and area under the curve of a receiver-operator curve (ROC) of the FaceReader algorithm. For this the quantitative data of facial weakness expressed in Action Units (AU), ranging between 0 (no activation) and +1 (maximal activation) will be used. Raw data from FaceReader provides the results of 20 AU's corresponding with 20 different facial movements of 20 facial muscles based on the Facial Action Coding System (FACS).

    2020-2023

  • Narrow deep learning model

    The primary parameter for the differentiation between healthy controls and MG and between different grades of MG disease severity with a working narrow deep learning model is the diagnostic yield. The diagnostic yield is expressed as sensitivity, specificity and area under the curve of a receiver-operator curve (ROC).

    2020-2023

  • Disease severity

    For comparison between different levels of disease severity the QMG score will serve as the gold standard. Groups based on disease severity are composed as following: mild QMG 0-9, moderate QMG 10-16 and severe QMG \>16. For the home recording we will use the MG-Activities of Daily Living (MG-ADL) to measure disease severity since the QMG requires the physical presence of the patient. This is a commonly used tool in clinical trials. Groups based on disease severity are composed as following: mild MG-ADL 0-4, moderate-severe MG-ADL ≥5.

    2020-2023

Secondary Outcomes (3)

  • Longitudinal changes

    2020-2023

  • FaceReader vs deep learning model

    2020-2023

  • site versus home recording

    2020-2023

Study Arms (2)

myasthenia gravis

healthy controls

Eligibility Criteria

Age18 Years+
Sexall
Healthy VolunteersYes
Age GroupsAdult (18-64), Older Adult (65+)
Sampling MethodNon-Probability Sample
Study Population

To answer the main objectives we will obtain a 04:00 min standardized facial video recording of MG patients in the outpatient clinic and Neurology ward, recorded at the LUMC. For the webcam recordings we will recruit participants from the Dutch-Belgian MG registry (P15.287). Informed consent forms of the MG registry with permission to be approached for future research are available. We will ask spouses and family to enrol as healthy controls, as well as employees of our department. The healthy control group will be age- and gender matched. Healthy controls are defined as subjects without medical conditions or medication which may influence the facial muscles, e.g. Graves thyroid disease, previous facial palsy due to a stroke or prednisone use. For the webcam recordings we will ask MG patients to introduce a healthy control of the same age.

You may qualify if:

  • Male or female participants aged ≥ 18 years
  • Subjects must understand the requirements of the study and provide written informed consent.
  • Clinical signs or symptoms suggestive of MG and at least one of the following:
  • A serologic test for AChR antibodies or MuSK antibodies or
  • A diagnostic electrophysiological investigation supportive of the diagnosis MG or
  • A positive neostigmine test Healthy control group
  • Volunteers from spouses, friends and family accompanying patient or employees from our department
  • No medical conditions affecting the facial muscles, e.g. Graves' disease, previous stroke with a facial palsy
  • No use of medication affecting the facial features, e.g. prednisone

You may not qualify if:

  • Inability to give written informed consent
  • Inability to read Dutch/ English video-instructions
  • Participants with active Graves' disease or unilateral facial paralysis

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Leiden University Medical Center

Leiden, South Holland, 2333ZA, Netherlands

Location

MeSH Terms

Conditions

Myasthenia Gravis

Condition Hierarchy (Ancestors)

Paraneoplastic Syndromes, Nervous SystemNervous System NeoplasmsNeoplasms by SiteNeoplasmsParaneoplastic SyndromesAutoimmune Diseases of the Nervous SystemNervous System DiseasesNeurodegenerative DiseasesNeuromuscular Junction DiseasesNeuromuscular DiseasesAutoimmune DiseasesImmune System Diseases

Study Officials

  • Martijn Tannemaat, MD, PhD

    Leiden University Medical Center

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
observational
Observational Model
CASE CONTROL
Time Perspective
PROSPECTIVE
Sponsor Type
OTHER
Responsible Party
PRINCIPAL INVESTIGATOR
PI Title
MD PhD

Study Record Dates

First Submitted

August 3, 2022

First Posted

March 6, 2025

Study Start

December 1, 2020

Primary Completion

December 31, 2022

Study Completion

December 31, 2022

Last Updated

March 6, 2025

Record last verified: 2025-03

Data Sharing

IPD Sharing
Will share

Raw data, including de-identified individual participants' data, that support the findings of this study are available from the corresponding author, upon reasonable request. Privacy laws preclude the sharing of facial videos of individual study participants.

Shared Documents
STUDY PROTOCOL, SAP, ICF, CSR

Locations