Retinal Neuro-vascular Coupling in Patients With Neurodegenerative Disease

NCT ID: NCT02663531

Last Updated: 2022-04-07

Basic Information

• Recruitment Status: UNKNOWN
• Clinical Phase: NA
• Total Enrollment: 150 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2016-09-27
• Study Completion Date: 2023-09-30

Brief Summary

Alzheimer´s disease (AD) in one of the most important causes of dementia and poses a considerable challenge in health care. Today, criteria for the diagnosis and the follow up of patients with AD mainly rely either on subjective tests or invasive methods. This limits the general applicability of the latter test for population screening and underlines the need for the identification of easily accessible tools for the identification of high-risk subjects. Because of its unique optical properties, the eye offers the possibility of the non-invasive assessment of both structural and functional alterations in neuronal tissue. As the neuro-retina is part of the brain, it does not come as a surprise that neuro-degenerative changes in the brain are accompanied by structural and possibly also functional changes in the neuro-retina and the ocular vasculature. The current study seeks to test the hypothesis that beside the known anatomical changes, also functional changes can be detected in the retina of patients with AD. For this purpose, flicker light induced hyperemia will be measured in the retina as a functional test to assess the coupling between neural activity and blood flow. Further, structural parameters such as retinal nerve fiber layer thickness and function parameters such as ocular blood flow and retinal oxygenation will be assessed and compared to age and sex matched controls.

Conditions

Mild Cognitive Impairment; Alzheimer Disease; Healthy

Study Design

• Allocation Method: RANDOMIZED
• Intervention Model: PARALLEL
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

Mild cognitive impairment

Patients with mild cognitive impairment

Group Type: EXPERIMENTAL

DVA

Intervention Type: DEVICE

FDOCT

Intervention Type: DEVICE

Pattern ERG

Intervention Type: DEVICE

Optical Coherence Tomography

Intervention Type: DEVICE

Alzheimer Disease

Patients with Alzheimer Disease

Group Type: EXPERIMENTAL

DVA

Intervention Type: DEVICE

FDOCT

Intervention Type: DEVICE

Pattern ERG

Intervention Type: DEVICE

Optical Coherence Tomography

Intervention Type: DEVICE

Healthy

Healthy volunteers

Group Type: EXPERIMENTAL

DVA

Intervention Type: DEVICE

FDOCT

Intervention Type: DEVICE

Pattern ERG

Intervention Type: DEVICE

Optical Coherence Tomography

Intervention Type: DEVICE

Interventions

DVA

Intervention Type: DEVICE

FDOCT

Intervention Type: DEVICE

Pattern ERG

Intervention Type: DEVICE

Optical Coherence Tomography

Intervention Type: DEVICE

Other Intervention Names

Dynamic Vessel Analyzer; Fourier Domain Color Doppler Optical Coherence Tomography

Eligibility Criteria

Inclusion Criteria

• Men and women aged over 50 years
• Non-smokers
• Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
• Normal ophthalmic findings, ametropia < 6 Dpt

• Men and women aged over 50 years
• Normal ophthalmic findings, ametropia < 6 Dpt.
• Confirmed diagnosis of probable AD of mild to moderate degree defined as:

1. Diagnosis of probable Alzheimer's disease based on the NINCDS/ADRDA criteria

2. Assessing the severity of Alzheimer's disease of mild to moderate degree by the Mini Mental State Examination (MMSE). AD of mild to moderate degree has been confirmed if the MMSE score is in the range of 20 to 26 inclusive

• Hachinski Ischemia Scale is used to try and distinguish AD from multi-infarct dementia. A score of ≤ 4 suggests AD Informed consent capability
• Adequate visual and auditory acuity to allow neuropsychological testing and participation in the ocular blood flow measurements
• A potential participant has to be on stable doses of all medications he/she is taking because of consisting illnesses according to medical history (except AD therapy itself which will be recorded separately) for at least 30 days prior inclusion, if considered relevant by the investigator.

• Men and women aged over 50 years
• Normal ophthalmic findings, ametropia < 6 Dpt.
• Diagnosis of probable mild cognitive impairment (MCI) defined as:

1. memory complaint, corroborated by an informant

2. abnormal memory function, documented by delayed recall of one paragraph from the Logical Memory II subtest of the Wechsler Memory Scale-Revised (cutoff scores: ≤8 for ≥16 years of education; ≤4 for 8 to 15 years of education; and ≤2 for 0 to 7 years of education [the maximum number of paragraph items possible to correctly recall is 25])

3. normal general cognitive function, as determined by a clinician's judgment based on a structured interview with the patient and an informant (Clinical Dementia Rating [CDR]) and a Mini-Mental State Examination (MMSE) score greater than 26

4. no or minimal impairment in activities of daily living (ADLs), as determined by a clinical interview with the patient and informant

5. not sufficiently impaired, cognitively and functionally, to meet the NINCDS/ADRDA criteria, as judged by an experienced AD research clinician

• Hachinski Ischemia Scale is used to try and distinguish MCI from multi-infarct dementia. A score of ≤ 4 suggests MCI Informed consent capability
• Adequate visual and auditory acuity to allow neuropsychological testing and participation in the ocular blood flow measurements
• A potential participant has to be on stable doses of all medications he/she is taking because of consisting illnesses according to medical for at least 30 days prior inclusion, if considered relevant by the investigator.

Exclusion Criteria

• Presence or history of a severe medical condition other than cognitive impairment as judged by the clinical investigator
• Untreated Arterial hypertension
• History or family history of epilepsy
• Presence of any abnormalities preventing reliable measurements in the study eye as judged by the investigator
• Best corrected visual acuity < 0.5 Snellen
• Ametropia greater than 6 Dpt
• pregnancy or planned pregnancy
• Major psychiatric disorder (e.g. schizophrenia), if considered relevant by the investigator
• Significant neurological disease other than AD or MCI, if considered relevant by the investigator
• Alcoholism or substance abuse

• Presence or history of a severe medical condition as judged by the clinical investigator
• Untreated Arterial hypertension
• History or family history of epilepsy
• Presence of any abnormalities preventing reliable measurements in the study eye as judged by the investigator
• Family history of AD
• Best corrected visual acuity < 0.5 Snellen
• Ametropia 6 Dpt
• Pregnancy or planned pregnancy

• Minimum Eligible Age: 50 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Medical University of Vienna

OTHER

Sponsor Role: lead

Responsible Party

Gerhard Garhofer

Assoc. Prof. PD Dr.

Responsibility Role: PRINCIPAL_INVESTIGATOR

Principal Investigators

Gerhard Garhöfer, MD

Role: PRINCIPAL_INVESTIGATOR

Department of Clinical Pharmacology, Medical University of Vienna

Locations

Department of Clinical Pharmacology, Medical University of Vienna

Vienna, , Austria

Site Status: RECRUITING

Countries

Austria

Central Contacts

Gerhard Garhöfer, MD

Role: CONTACT

gerhard.garhoefer@medunwien.ac.at

0043140400 ext. 29810

Facility Contacts

Gerhard Garhöfer, MD

Role: primary

gerhard.garhoefer@meduniwien.ac.at

+43 (1) 40400 ext. 29810

Other Identifiers

OPHT-180515

Identifier Type: -

Identifier Source: org_study_id