Measurement of the Effect of Gingko Biloba Extract on Ocular and Nailfold Blood-flow in NTG

Normal Tension Glaucoma Clinical Trial

Official title:

Measurement of the Effect of Gingko Biloba Extract on Ocular and Nailfold Blood-flow in Normaltension Glaucoma by Ocular Coherence Tomography Angiography and Nailfold Capillaroscopy

Clinical Trial Details — Status: Recruiting

Administrative data

• NCT number: NCT03761992
• Other study ID #: NFC Gingko
• Status: Recruiting
• Phase: N/A
• Start date: November 19, 2018
• Est. completion date: December 2020

Study information

• Verified date: March 2020
• Source: Robert Ritch, MD, LLC.
• Contact: Robert Ritch, MD
• Phone: 212-477-7540
• Email: rritch[@]nyee.edu
• Is FDA regulated: No
• Study type: Interventional

Clinical Trial Summary

The purpose of this study is to evaluate the effect of Ginkgo biloba extract (GBE) on the number of blood vessels in the back of the eye as well as the amount of blood flow at the nailfold(where the fingernail meets the skin) of the 4th finger in the hand.This finger, along with the 5th finger, has the most transparent skin, which makes imaging a little easier. GBE is an over-the-counter pill, made from a natural powder taken from the Gingko (Maidenhair) tree, that is widely used. A technique called Optical Coherence Tomography Angiography (OCTA),will be used to measure the small blood vessels at the back of the eye, the macula (the area of sharpest vision), and the optic disc (the point at which the nerve fibers from the retina enter to form the optic nerve, which transmits visual impulses to the brain).

Description:

GBE has been reported to improve blood flow to the brain, eye, and extremeties(hands, feet,etc.). .As with most supplements, GBE is neither regulated nor FDA approved.

A technique called Optical Coherence Tomography Angiography (OCTA),will be used to measure the small blood vessels at the back of the eye, the macula (the area of sharpest vision), and the optic disc (the point at which the nerve fibers from the retina enter to form the optic nerve, which transmits visual impulses to the brain). This technique uses a camera, capable of imaging the smallest vessels, so that their density (number) can be calculated by a computer. This is being done to determine if there is disease causing increasing loss of these vessels. The imaging is done by a widely used camera which does not contact the eye. It simply uses visible light to measure the amount of blood vessels present in a determined area in the back of the eye. Blood flow at the 4th finger nailfold (nailfold capillaroscopy; NFC) is a standard technique, especially in rheumatology, performed by using a commercially available light microscope which glides over the base of the fingernail and can image the tiny capillaries in the nailfold. These images are recorded as videos from which the blood flow can be analyzed by freely available software for the purpose of quantitative measurements (amount of blood flow and blood flow velocity).

Recruitment information / eligibility

• Status: Recruiting
• Enrollment: 40
• Est. completion date: December 2020
• Est. primary completion date: November 2020
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years and older

Eligibility

Inclusion Criteria:

Male or female of any race, at least 18 years of age

• Has provided verbal and written informed consent.

• Able and willing to follow instructions, including participation in all study assessments and visits.

• Eyes with NTG will be enrolled.

• Glaucoma severity will be graded using the WHO (World Health Organization)staging system.

NTG diagnosis will be based on the following:

1. Glaucomatous optic disc on slit-lamp biomicroscopy defined as cup-to-disc ratio greater than 0.7, inter-eye asymmetry in cup-to-disc ration greater than 0.2 or neuroretinal rim notching, focal thinning, disc hemorrhage or vertical elongation of optic disc.

2. Glaucomatous visual field defects on at least three reliable visual field examinations as measured by a glaucoma hemifield test (GHT) result outside normal limits and/or the appearance of at least three consecutive test points on the pattern deviation plot with p<1% and at least one at p<0.05%, not including points on the edge of the field.

3. NTG will be defined as those subjects with a history of untreated peak IOP =21 mmHg.

• Both eyes will be enrolled

Exclusion Criteria:

• Best-corrected visual acuity less than 20/40

• Age younger than 18 years or older than 85 years

• Refractive error greater than +3.00 diopters (D) or less than -7.00 diopters (D)

• Previous intraocular surgery except for uncomplicated cataract extraction with posterior chamber intraocular lens implantation

• Any other diseases that may cause visual field loss or optic disc abnormalities

• Inability to perform reliably on automated visual field testing.

• Subjects taking any GBE product will be washed out for 2 weeks prior to enrollment.

• Diabetes.

• Seizure disorder.

• Taking any drugs that may interact with GBE (as listed).

Related Conditions & MeSH terms

• Glaucoma
• Low Tension Glaucoma
• Normal Tension Glaucoma

Intervention

Dietary Supplement:
• Gingko Baloba
Tablets

Other:
• Placebo
Tablets

Locations

Country	Name	City	State
United States	New York Eye and Ear Infirmary of Mount Sinai	New York	New York

Sponsors (1)

Lead Sponsor	Collaborator
Robert Ritch, MD, LLC.

Country where clinical trial is conducted

United States, 

References & Publications (4)

Flammer J, Konieczka K, Flammer AJ. The primary vascular dysregulation syndrome: implications for eye diseases. EPMA J. 2013 Jun 7;4(1):14. doi: 10.1186/1878-5085-4-14. — View Citation

Kim KE, Park KH. Update on the Prevalence, Etiology, Diagnosis, and Monitoring of Normal-Tension Glaucoma. Asia Pac J Ophthalmol (Phila). 2016 Jan-Feb;5(1):23-31. doi: 10.1097/APO.0000000000000177. Review. — View Citation

Pasquale LR. Vascular and autonomic dysregulation in primary open-angle glaucoma. Curr Opin Ophthalmol. 2016 Mar;27(2):94-101. doi: 10.1097/ICU.0000000000000245. Review. — View Citation

Quigley HA, Broman AT. The number of people with glaucoma worldwide in 2010 and 2020. Br J Ophthalmol. 2006 Mar;90(3):262-7. — View Citation

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Primary Outcome - Measure of Blood Vessel by Optical Cohrence Tomography Angiography (OCTA)	The investigators plan to evaluate the density of the small blood vessels at the back of the eye. This will be measured by a OCTA. A camera capable of imaging the smallest vessels so that their density (number) can be calculated by a computer, the purpose being to determine if there is disease causing progressive loss of these vessels.	4 weeks
Secondary	Secondary Outcome - Measure of Blood Flow and Velocity by Nailfold Capillaroscopy (NFC)	Measuring blood flow at the 4th finger nailfold by NFC is a standard technique, especially in rheumatology, in which a commercially available light microscope glides over the base of the fingernail to image the tiny capillaries in the nailfold. These images are recorded as videos from which the blood flow can be analyzed quantitatively by freely available software to measure blood flow and velocity.	4 weeks