Retinal Oxygen Function After Radiation Therapy

A History of Radiation Therapy for a Tumor in the Vicinity of the Retina(s) Clinical Trial

Official title:

Changes in Regional Retinal Oxygen Extraction and Function After Radiation Therapy

Clinical Trial Details — Status: Completed

Administrative data

• NCT number: NCT02043470
• Other study ID #: LCCC 1019
• Status: Completed
• Start date: March 2011
• Est. completion date: May 4, 2017

Study information

• Verified date: May 2017
• Source: UNC Lineberger Comprehensive Cancer Center
• Contact: n/a
• Is FDA regulated: No
• Study type: Observational

Clinical Trial Summary

The investigators propose using retinal oximetry to assess for abnormalities in regional retinal oxygen consumption in previously- irradiated patients, and relate these abnormalities to changes in regional retinal function (i.e. visual field abnormalities). Since different regions of retina receive different radiation doses, the investigators will assess for a dose response as well.

Description:

Radiation therapy (RT) is a common treatment for patients with cancers of the sinonasal area, orbit, skull base, nasopharynx, and brain. Because of the close proximity of these targets to the eyes, the retina is often incidentally and unavoidably irradiated. As a result, some patients develop radiation retinopathy and possibly vision loss. Clinicopathologic studies suggest similar microvascular mechanisms for both radiation- and diabetic retinopathy: small vessel occlusion and ischemia that can lead to neovascularization, increased capillary permeability, and visual loss in the regions of retina perfused by damaged vasculature. UNC has a novel, non-invasive retinal imaging technology called a Retinal Oximeter which measures hemoglobin oxygen saturation of retinal vessels. The difference in oxygen saturation between a retinal arteriole and venule pair reflects the oxygen consumption of the retinal region supplied by that vessel pair.

Recruitment information / eligibility

• Status: Completed
• Enrollment: 32
• Est. completion date: May 4, 2017
• Est. primary completion date: July 2015
• Accepts healthy volunteers: No
• Gender: All
• Age group: 18 Years to 99 Years

Eligibility

Inclusion Criteria:

1. = 18 years of age at the time of radiation therapy (no upper age limit)

2. History of radiation therapy delivered at UNC-CH or Rex Hospital to the vicinity of the retina(s) = 2 months prior to enrollment

3. Estimated average dose to at least one quadrant of one retina = 30 Gy

Exclusion Criteria:

1. History of diabetes, retinal vascular occlusions, glaucoma, retinitis pigmentosa, occipital stroke or any other ophthalmologic or systemic problem that may confound visual field results.

2. Residual tumor within the visual pathway: retina, optic nerves, optic chiasm, optic radiations and brain.

Related Conditions & MeSH terms

• A History of Radiation Therapy for a Tumor in the Vicinity of the Retina(s)

Locations

Country	Name	City	State
United States	Department of Radiation Oncology Clinic	Chapel Hill	North Carolina

Sponsors (2)

Lead Sponsor	Collaborator
UNC Lineberger Comprehensive Cancer Center	UNC Translational and Clinical Sciences (Tracs)

Country where clinical trial is conducted

United States, 

Outcome

Type	Measure	Description	Time frame	Safety issue
Primary	Abnormalities in regional retinal oxygen extraction after incidental irradiation of the retina.	To identify abnormalities in regional retinal oxygen extraction in patients who have had previous incidental irradiation of the retina.	2 months
Primary	Prevalence of vision loss in patients with previous incidental irradiation of the retina	To determine the prevalence of regional retinal dysfunction (i.e. vision loss) in patients with previous incidental irradiation of the retina.	2 months
Secondary	Changes in retinal oxygen extraction compared to radiation dose	To correlate changes in retinal oxygen extraction to radiation dose.	2 months
Secondary	Vision loss amount versus radiation dose.	To correlate retinal dysfunction (i.e. vision loss) to radiation dose.	2 months
Secondary	Changes in retinal oxygen extraction as compared to vision loss.	To correlate changes in retinal oxygen extraction to retinal dysfunction (i.e. vision loss).	2 months