Assessing how pupils respond to light in Parkinson's disease patients

Assessment of Pupil Light Reflex in Patients With Parkinson Disease in Comparison to Healthy Subjects.

Observational Sheba Medical Center · NCT04117555

This study is testing how well the pupils of people with Parkinson's disease respond to light to see if it can help spot the disease earlier and track its progress.

Quick facts

Study typeObservational
Enrollment200 (estimated)
Ages30 Years to 75 Years
SexAll
SponsorSheba Medical Center Government
Locations1 site (Tel HaShomer)
Trial IDNCT04117555 on ClinicalTrials.gov

What this trial studies

This observational study aims to evaluate pupil light responses in patients diagnosed with Parkinson's disease and related neurodegenerative conditions. By comparing these responses to those of healthy controls, the study seeks to explore the feasibility of using pupillometry as a diagnostic tool for early detection and monitoring of Parkinson's disease. The research focuses on individuals aged 30-75 years, assessing their pupillary reflex to light stimuli to identify potential biomarkers for the disease. The findings could lead to improved interventions and monitoring strategies for patients with Parkinson's disease.

Who should consider this trial

Good fit: Ideal candidates include individuals aged 30-75 with clinical presentations of Parkinson's disease or related neurodegenerative disorders.

Not a fit: Patients with normal eye examinations and no history of ocular disease or surgery may not benefit from this study.

Why it matters

Potential benefit: If successful, this study could provide a new diagnostic biomarker for early detection and monitoring of Parkinson's disease.

How similar studies have performed: Previous proof of concept studies have indicated significant differences in pupil light responses between Parkinson's disease patients and healthy controls, suggesting potential for this approach.

Eligibility criteria

Show full inclusion / exclusion criteria
Inclusion Criteria:

* General inclusion criteria

  1. Age 30-75 years old
  2. Signed written informed consent
  3. Gender: Both (Male and Female)
  4. Pupillary reflex to light.
  5. Clear ocular media

Patients' Inclusion Criteria:

Patients with clinical presentations of the neurodegenerative forms of parkinsonism (bradykinesia, extrapyramidal rigidity, tremor, postural instability and gait disturbance) including: idiopathic Parkinson disease (PD), Lewy body disease (LBD), progressive supranuclear palsy (PSP), multiple system atrophy (MSA), corticobasal degeneration (CBD) and secondary parkinsonisms.

Control group- inclusion criteria

1. Normal eye examination
2. Best-corrected visual acuity (BCVA) of 20/20
3. Normal color vision test (Farnsworth/Lanthon D-15 Test)
4. No present ocular disease
5. No past ocular disease or surgery within last 6 months
6. No use of any topical or systemic medications that could adversely influence efferent pupil movements
7. Normal 24-2 Humphrey visual field and

   * Short duration (≤10 minutes)
   * Minimal fixation losses, False positive errors and False negative errors (less than 30% for each one of reliability indices)

Exclusion Criteria:

1. Diagnosis of dementia.
2. Cognitive decline that may impair obtaining informed consent.
3. Tremor or dyskinesia that could interfere with ophthalmic evaluation
4. History of past (last 3 months) or present ocular disease or ocular surgery
5. Use of any topical or systemic medications that could adversely influence pupillary reflex
6. Psychiatric illness, active psychosis.
7. Previous neurosurgical interventions, including stereotactic neurosurgical procedures.
8. Past or current strokes or brain injury and other brain disorders (except PD/parkinsonism for patient group)
9. Anti-dopaminergic drugs.
10. Intolerance to gonioscopy, slit lamp examination, Goldmann applanation tomometry or other schedule study procedure.
11. Visual media opacity including cloudy corneas.
12. Any condition preventing accurate measurement or examination of the pupil.

Where this trial is running

Tel HaShomer

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions Parkinson Disease
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.