An observational study in Parkinson Disease, sponsored by Landspitali University Hospital. Active, not recruiting at 1 site in Iceland. Open to participants aged 18 Years and older, including healthy volunteers. Per ClinicalTrials.gov, last updated 2025-04-15.
Sponsored by Landspitali University Hospital · Observational
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:
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.
4,583 studies on the registry are indexed under Parkinson Disease; 1,097 are open to participants now.
This study's planned enrollment of 60 is below the median of 97 across 1,081 observational studies indexed under Parkinson Disease.
Browse Parkinson Disease studies →Landspitali University Hospital is the lead sponsor of 21 studies on the registry; 6 are open to participants now.
Counted across the registry records on this site, refreshed daily.
People with confirmed parkinsons disease Stage 0-3 on the Hohen and Yahr scale
Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Retinal vessels oxyhemoglobin saturation
Obtained by retinal oximetry
Time frame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
Vessel width of retinal arterioles and venules
Obtained by retinal oximetry
Time frame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
Retinal nerve fiber layer thickness
Obtained by cross-sectional imaging of the retinal tissue (OCT)
Time frame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
Components and waveform of VEPs
Pattern electroretinogram (PERG)
Time frame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
Pattern electroretinograms (PERGs)
Amplitude of the visual evoked potential response
Time frame: Baseline. On the visit to the ambulatory Opthalamic department at Landspitali
Started Mar 2023 (actual). Primary completion is estimated for Dec 2026, 45 months after the start.
How these figures are worked out, and which studies are left out of them.
This study is active, not recruiting, as verified in Apr 2025. You cannot join it, but the record below documents what was studied.
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Landspitali University Hospital