US 11,733,029 B2
Method for estimating shape parameters of the fovea by optical coherence tomography
Alexander Brandt, Wesel (DE); Ella Maria Kadas, Berlin (DE); Sunil Yumar Yadav, Berlin (DE); Seyedamirhosein Motamedi, Berlin (DE); and Paul Friedemann, Berlin (DE)
Assigned to CHARITÉ UNIVERSITÄTSMEDIZIN BERLIN, Berlin (DE)
Appl. No. 16/632,340
Filed by CHARITÉ UNIVERSITÄTSMEDIZIN BERLIN, Berlin (DE)
PCT Filed Jul. 19, 2018, PCT No. PCT/EP2018/069640
§ 371(c)(1), (2) Date Jan. 18, 2020,
PCT Pub. No. WO2019/016319, PCT Pub. Date Jan. 24, 2019.
Claims priority of application No. 17182192 (EP), filed on Jul. 19, 2017.
Prior Publication US 2020/0170503 A1, Jun. 4, 2020
Int. Cl. G01B 9/02091 (2022.01); A61B 3/10 (2006.01); G06T 7/00 (2017.01)
CPC G01B 9/02091 (2013.01) [A61B 3/102 (2013.01); G06T 7/0012 (2013.01); G06T 2207/10101 (2013.01); G06T 2207/30041 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A method for estimating shape parameters of an image data set (1) of a fovea (100), comprising the steps of:
Acquiring an image data set (1) of the macula (50) of an eye, the macula comprising a foveal pit (101) and a foveal rim (102),
Estimating the center of the foveal pit (101) from the image data set (1),
Estimating from the center of the foveal pit (101), radially extending height profiles (c) of the fovea (100),
For each height profile (c), fitting a model-function to the height profile (c),
Estimating for each height profile (c) a set of fit parameters from the fitted model-function, and
Determining from the sets of fit parameters at least one shape parameter of the fovea (100),
wherein the model function is a smooth composite Bézier path comprising cubic Bézier functions, and
wherein each height profile (c) comprises an interior segment (cI) and an exterior segment (cE), wherein the height profiles (c) are fitted with the smooth composite Bézier path, wherein a first Bézier function (QI) is fitted to the interior segment (cI) and wherein a second Bézier function (QE) is fitted to the exterior segment (cE), wherein the interior segment (cI) extends between a first end point (P0I) and a second end point (P3I) of the first Bézier function (QI), and the exterior segment (cE) extends between a first end point (P0E) and a second end point (P3E) of the second Bézier function (QE), wherein the second end point (P3I) of the first Bézier function (QI) is identical or adjoining with the first end point (P0E) of the second Bézier function (QE), wherein the first end point (P0I) of the first Bézier function (QI) is at a first end of the height profile (c), the second end point (P3I) of the first Bézier function (QI) and the first end point (P0E) of the second Bézier function (QE) are identical at a maximum rim height of the height profile (c) and the second end point (P3E) of the second Bézier function (B2) is at a second end of the height profile (c), wherein the first and second Bézier function (QI, QE) have the same slope at the second end point (P3I) of the first Bézier function (QI) and the identical first end point (P0E) of the second Bézier function (QE).