Calibration of imaging system with combined optical coherence tomography and visualization module

Patent metadata

Field	Value
Publication number	US-12422247-B2
Application number	US-202318354096-A
Country	US
Kind code	B2
Filing date	Jul 18, 2023
Priority date	Jul 21, 2022
Publication date	Sep 23, 2025
Grant date	Sep 23, 2025

Abstract

An imaging system includes a housing assembly having a head unit configured to be at least partially directed towards a target site. An optical coherence tomography (OCT) module and a visualization module are located in the housing assembly and configured to respectively obtain OCT data and visualization data of the target site. The system includes a controller configured to generate a scanning pattern for a region of calibration selected in a calibration target. OCT data of the region of calibration is synchronously acquired. The controller is configured to obtain a projected two-dimensional OCT image of the region of calibration based on the OCT data, as an inverse mean-intensity projection. The controller is configured to register the projected two-dimensional OCT image to a corresponding view extracted from the visualization data, via a cascaded image registration process having a coarse registration stage and a fine registration stage.

First claim

What is claimed is:

1. An imaging system comprising:
a housing assembly having a head unit configured to be at least partially directed towards a target site;
an optical coherence tomography (OCT) module and a visualization module located in the housing assembly and configured to respectively obtain OCT data and visualization data of the target site;
a controller in communication with the OCT module and the visualization module, the controller having a processor and tangible, non-transitory memory on which instructions are recorded for a method of calibration;
wherein the controller is configured to:
generate a scanning pattern for a region of calibration selected in a calibration target in visualization space;
synchronously acquire the OCT data of the region of calibration with the scanning pattern;
obtain a projected two-dimensional OCT image of the region of calibration based on the OCT data, the projected two-dimensional OCT image being an inverse mean-intensity projection on an en face viewing plane;
overlay the projected two-dimensional OCT image with a corresponding view extracted from the visualization data; and
register the projected two-dimensional OCT image to the corresponding view, via a cascaded image registration process having a coarse registration stage and a fine registration stage.

2. The imaging system of claim 1 , wherein the visualization module is a stereoscopic camera, the visualization data including first and second views of the target site.

3. The imaging system of claim 1 , wherein the visualization module is a surgical microscope.

4. The imaging system of claim 1 , wherein the scanning pattern is an orthogonal raster scanning pattern.

5. The imaging system of claim 1 , wherein the target site is an eye.

6. The imaging system of claim 1 , wherein prior to registering the projected two-dimensional OCT image with the corresponding view extracted from the visualization data, the controller is configured to perform automatic image resizing.

7. The imaging system of claim 1 , wherein the controller is adapted to calculate respective transformation parameters in the coarse registration stage based on a translation transformation matrix that compensates for mismatches in shift.

8. The imaging system of claim 1 , wherein:
the controller is adapted to calculate respective transformation parameters in the fine registration stage based on an affine diffusion tensor image (DTI) registration; and
the respective transformation parameters are based in part on a rotation matrix, a shear matrix and a scaling matrix.

9. The imaging system of claim 8 , wherein the controller is adapted to compensate for relatively small mismatches in shift introduced during operation of at least one of rotation, shear and scaling alignment.

10. The imaging system of claim 8 , wherein the rotation matrix is expressed as

[

cos
⁡
(
θ
)

-

sin
⁡
(
θ
)

sin
⁡
(
θ
)

cos
⁡
(
θ
)

]

,

where θ is the respective transformation parameter for rotation.

11. The imaging system of claim 8 , wherein the shear matrix is expressed as

[

1

Shx

Shy

1

]

,

where Shx and Shy are shear parameters along a first transverse direction and a second transverse direction.

12. The imaging system of claim 8 , wherein the scaling matrix is expressed as

[

Cx

0

0

Cy

]

,

where Cx and Cy are scaling parameters along a first transverse direction and a second transverse direction.

13. The imaging system of claim 1 , wherein the controller is adapted to selectively execute a validation procedure, the controller being adapted to:
select a region of interest in the visualization space;
obtain respective voltages for OCT scanning based in part on the region of interest and respective transformation parameters;
obtain acquired OCT image based on the respective voltages; and
compare the acquired OCT image with the region of interest.

14. The imaging system of claim 13 , wherein the region of interest is a line in the visualization space that corresponds to a cross-sectional B-frame in OCT space.

15. The imaging system of claim 13 , wherein the region of interest is a quadrilateral in the visualization space that corresponds to a three-dimensional volume in OCT space.

16. The imaging system of claim 1 , further comprising:
a robotic arm operatively connected to and configured to selectively move the head unit; and
wherein the robotic arm is selectively operable to extend a viewing range of the OCT module in three dimensions.

17. An imaging system comprising:
a housing assembly having a head unit configured to be at least partially directed towards a target site;
an optical coherence tomography (OCT) module and a visualization module located in the housing assembly and configured to respectively obtain OCT data and visualization data of the target site;
a controller in communication with the OCT module and the visualization module, the controller having a processor and tangible, non-transitory memory on which instructions are recorded for a method of calibration;
wherein the controller is configured to:
generate a scanning pattern for a region of calibration selected in a calibration target in visualization space;
synchronously acquire the OCT data of the

Assignees

• Alcon Inc

Inventors

• Wei Wei
• Rabbani Parisa
• Hosseinzadeh Kassani Sahar
• Li Qiang
• Noller Lance

Classifications

• G01B9/02091

  Tomographic interferometers, e.g. based on optical coherence · CPC title

• A61B3/102

  for optical coherence tomography [OCT] · CPC title

• A61B90/20

  Surgical microscopes characterised by non-optical aspects · CPC title

• A61B3/132

  in binocular arrangement · CPC title

• A61B3/12

  for looking at the eye fundus, e.g. ophthalmoscopes (A61B3/13 takes precedence) · CPC title