Evaluation of a Novel Method for Increasing Intraocular Pressure in Healthy Subjects

NCT ID: NCT04044274

Last Updated: 2022-04-07

Basic Information

• Recruitment Status: COMPLETED
• Clinical Phase: NA
• Total Enrollment: 13 participants
• Study Classification: INTERVENTIONAL
• Study Start Date: 2019-07-24
• Study Completion Date: 2021-02-02

Brief Summary

Adequate perfusion is necessary for maintaining tissue function. This applies also for the eye, in which ocular perfusion pressure (OPP) is generally estimated as the difference between mean arterial pressure (MAP) and intraocular pressure (IOP). In the latter formula, IOP substitutes for central retinal venous pressure (CRVP), which is assumed to be slightly higher than IOP to allow blood flow to exit the eye. It has, however, been found that in some patients CRVP is elevated and significantly higher than IOP, which would lead to a decrease in OPP which is not taken in account with the proposed formula. Therefore, techniques for measurement of CRVP are warranted. Recently, a new, method for measurement of this parameter without corneal contact has been introduced. Briefly, with this method, IOP is elevated until the vein collapses, which then equals CRVP. In the present study this technique will be applied in 12 healthy subjects to validate whether the values that are preset by the device correlate to measurements obtained with standard Goldmann applanation tonometry. For this purpose, IOP will be experimentally increased in steps of approximately 5mmHg until it reaches 40mmHg as measured by applanation tonometry. After a resting period of 30 minutes, IOP will be again increased stepwise to 40 mmHg while retinal vessel diameters will be monitored using dynamic vessel analyzer. During this session CRVP will be measured. After another resting period of 30 minutes IOP will be stepwise increased a third time and after each step OCT, OCT-A and OCT EDI will be performed.

Conditions

Intraocular Pressure

Study Design

• Allocation Method: NA
• Intervention Model: SINGLE_GROUP
• Primary Study Purpose: BASIC_SCIENCE
• Blinding Strategy: NONE

Study Groups

IOPstim

Group Type: EXPERIMENTAL

IOPstim

Intervention Type: DEVICE

IOPstim (IMEDOS, Jena, Germany) is a device exerting defined pressure to the sclera and hence increasing IOP.

Suction Cup

Intervention Type: DEVICE

Suction Cup is a device exerting defined suction to the clear and hence increasing IOP

Interventions

IOPstim

IOPstim (IMEDOS, Jena, Germany) is a device exerting defined pressure to the sclera and hence increasing IOP.

Intervention Type: DEVICE

Suction Cup

Suction Cup is a device exerting defined suction to the clear and hence increasing IOP

Intervention Type: DEVICE

Eligibility Criteria

Inclusion Criteria

• Men and women aged between 18 and 35 years
• Non-smokers
• Normal findings in the medical history unless the investigator considers an abnormality to be clinically irrelevant
• Normal ophthalmic findings, ametropia < 1 Dpt.

Exclusion Criteria

• Regular use of medication, abuse of alcoholic beverages, participation in a clinical trial in the 3 weeks preceding the study
• Treatment in the previous 3 weeks with any drug (except contraceptives)
• Symptoms of a clinically relevant illness in the 3 weeks before the first study day
• Blood donation during the previous 3 weeks
• Pregnancy, planned pregnancy or lactating

• Minimum Eligible Age: 18 Years
• Maximum Eligible Age: 35 Years
• Eligible Sex: ALL
• Accepts Healthy Volunteers: Yes

Sponsors

Medical University of Vienna

OTHER

Sponsor Role: lead

Responsible Party

Gerhard Garhofer

Assoc. Prof. Priv.-Doz. 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

Countries

Austria

Other Identifiers

OPHT-120219

Identifier Type: -

Identifier Source: org_study_id