Apparatus and method for automatically determining a strabismus angle

Apparatus and method for automatically determining a strabismus angle

Schutte, S.
Geukers, E.B.M.
Simonsz, H.J.
Van der Helm, F.C.T.

Mechanical, Maritime and Materials Engineering

Biomechanical Engineering

2011-02-24

Apparatus and method for automatically determining a strabismus angle of the eyes of an individual by performing a reflection test on said eyes, comprising the steps of : -directing at least a first beam of light onto said eyes of the individual; -having the individual focus its eyes; -using at least one imaging device for: measuring the light beam reflected from the eyes for establishing which eye is fixating, and performing a reflex test on both eyes to estimate the strabismus angle, wherein -the reflex test is carried out by applying at least two light sources at known differing positions and measuring the corneal reflections of said light sources in both eyes by monitoring said corneal reflections by an imaging device or devices; -the said corneal reflections are used to derive corneal center coordinates for both eyes individually; -for both eyes individually pupil center coordinates are estimated; -the corneal center coordinates and the pupil center coordinates of both eyes are used to estimate the strabismus angle. For the eye that is fixating an angle kappa is calculated representing an angle between the eyes' optical axis through the corneal center and the pupil center, and the visual axis through the corneal center and the eye's fovea, and the angle kappa is then used for determining the strabismus angle.

http://resolver.tudelft.nl/uuid:d5a6799b-38cf-40e9-803c-f795f35af41d

European Patent Office

http://worldwide.espacenet.com/publicationDetails/biblio?CC=WO&NR=2011021936A1&KC=A1&FT=D&date=20110224&DB=EPODOC&locale=en_EP

WO 2011021936 (A1)

Institutional Repository

patent

(c) 2011 The Author(s)