Clinical trial NCT06929026: Retinal Biomarkers in Parkinson´s Disease
Official title: Retinal Biomarkers in Parkinson´s Disease: Retinal Oximetry, Pattern Electroretinography (PERG), Visual Evoked Potentials (VEP) and Optical Coherence Tomography (OCT)
Study type: OBSERVATIONAL
Overall status: ACTIVE_NOT_RECRUITING
Conditions: Parkinson Disease
Keywords: Retinal oximetry
Pattern Electroretinography
Visual Evoked Potentials
Optical Coherence Tomography
Oxyhemoglobin saturation
Lead sponsor: Landspitali University Hospital
Sponsor class: OTHER
Collaborators: name: Reykjalundur Rehabilitation
name: University of Iceland
First posted: 2025-04-15
Enrollment: 60
Sex: ALL
Minimum age (years): 18
Standard ages: ADULT
OLDER_ADULT
Accepts healthy volunteers: yes
Observational model: CASE_CONTROL
Time perspective: CROSS_SECTIONAL
Sampling method: NON_PROBABILITY_SAMPLE
Study population: People with confirmed parkinsons disease Stage 0-3 on the Hohen and Yahr scale

Brief summary: The goal of this observational study is to determine whether oxygen content of the retinal vessels of the eye may serve as a biomarker in Parkinson´s disease. The main questions it aims to answer are:

1. Is retinal vessel oxyhemoglobin saturation and vessel width altered in people with Parkinson´s disease?
2. Is the thickness of the retinal nerve fiber layer altered in people with Parkinson´s disease?
3. Is the response of ganglion cells of the inner retina and the visual cortex altered in people with Parkinson´s disease?

The study procedure is threefold. The participants will:

A. Sit in front of a screen and focus on a red dot of its middle. A simple recording electrodes are applied on the cornea, forehead and scalp for the electrophysiological measurements. Prior to this procedure a topical anesthetic gel is applied to numb the eye to prevent discomfort from placement of the corneal electrodes.

B. Undergo general eye examination and optical coherence tomography (OCT) to measure the retinal tissue thickness. Prior to eye examination,eye drops are applied into the eyes to enlarge the pupils C. Sit in front of a fundus camera for obtaining images of the retinal vessels to measure oxygen saturation and the vessel width

Researchers will compare the obtained measurements with age- and gender matching of healthy controls.


Eligibility criteria: Inclusion Criteria:

* Confirmed Parkinson Disease

Exclusion Criteria:

* Eye disease
* Diabetic Mellitus
* Chronic Obstructive Pulmonary Disease (COPD)
* Other Neurological Disease
* Smoking on a daily basis

Primary outcomes:
measure: Retinal vessels oxyhemoglobin saturation
timeFrame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
Secondary outcomes:
measure: Vessel width of retinal arterioles and venules
timeFrame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
measure: Retinal nerve fiber layer thickness
timeFrame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
measure: Components and waveform of VEPs
timeFrame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
measure: Pattern electroretinograms (PERGs)
timeFrame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
Other outcomes:
Locations:
city: Reykjavik
country: Iceland
facility: Ophthalmic Outpatient Department Landspitali UH
Study officials:
affiliation: University Hospital of Iceland and University of Iceland. Reykjalundur
name: Thorunn S Eliasdottir, PhD, CRNA
role: PRINCIPAL_INVESTIGATOR
affiliation: Landpitali the University Hopital of Iceland
name: Thorunn S Eliasdottir, PhD, CRNA
role: PRINCIPAL_INVESTIGATOR
affiliation: University of Iceland
name: Thorunn S Eliasdottir, PhD, CRNA
role: PRINCIPAL_INVESTIGATOR
affiliation: Reykjalundur
name: Soley Thrainsdottir, MD, PhD
role: PRINCIPAL_INVESTIGATOR
References: