Non-invasive Measurement of Hemoglobin in Retinal Arteries

Non- Invasive Measurement of the Absolute Hemoglobin Value in the Retinal Arteries of Anemic and Healthy Subjects Using a New Approach

The purpose of this study is to test a new non-invasive tool to measure hemoglobin in retinal arteries.

To our knowledge no tool exists that allows for direct collection of hemoglobin data in the eye. In many eye diseases (especially diabetic and hypertensive retinopathy as well as in retinal vessel occlusions) retinal circulation is modified. Knowing hemoglobin concentration on the site of the pathology will give us further information about the pathogenesis of this diseases and may provide a new possibility in therapy.

The purpose of this study is to test a new non-invasive tool to measure hemoglobin in retinal arteries. Healthy volunteers from the eye clinic and pregnant otherwise healthy patients of the gynecological department of the Triemli Hospital, Zurich, as well as anemic gynecological patients that show up for a check-up are included.

Hemoglobin will be quantified by a blood draw of a cubital vein. Using a Fundus Camera (Nidek AFC-230) pictures of the fundus will be taken from each study patient. Afterwards the study investigator selects a retinal artery of interest which will be used for measuring the hemoglobin concentration. Intensity of the green channel of the camera chip is determined with the aid of the law of Lambert-Beer.

Absolute Hemoglobin concentration is calculated in relation to the vessel volume.

Inclusion Criteria:

• healthy volunteers
• pregnant patients from the Triemli Hospital that came for a routine check up
• anemic patients of the same dept with various gynecological tumors

Exclusion Criteria:

• any known retinal eye disease
• poor fundus picture quality due to fixtion problems or too small pupil or media intransparency
• not willing to participate in a study