Method of tracking a plurality of objects

Patent metadata

Field	Value
Publication number	US-11295546-B2
Application number	US-201916978656-A
Country	US
Kind code	B2
Filing date	Mar 7, 2019
Priority date	Mar 8, 2018
Publication date	Apr 5, 2022
Grant date	Apr 5, 2022

Abstract

Method of tracking a plurality of objects comprising: focusing an image of the objects on an imaging element using an optical system; capturing the image of the objects using an imaging element comprising a plurality of pixels; measuring at least one characteristic of the objects from the captured image using an image processor; wherein the field of view is set be the widest field of view for which the image processor is able to measure the at least one characteristic.

First claim

The invention claimed is:

1. A method of tracking a plurality of objects, wherein the objects are nematode worms, comprising:
focusing an image of the objects on an imaging element using an optical system;
capturing image frames of the objects using the imaging element comprising a plurality of pixels;
measuring at least one characteristic of the objects from the captured image using an image processor;
wherein a field of view of the optical system is set to be the widest field of view for which the image processor is able to measure the at least one characteristic, and the field of view is determined based on the average size of the objects and a predefined minimum resolution required for the image processor to measure the at least one characteristic; and
wherein the at least one characteristic comprises one or more of: bends per minute, bending amplitude, length, translational speed and paralysis rate.

2. The method of claim 1 , wherein the at least one characteristic comprises bends per minute.

3. The method of claim 1 , wherein the at least one characteristic comprises length and/or translational speed and the predefined resolution is the resolution at which the objects are still detectable by the image processor.

4. The method of claim 1 , wherein the at least one characteristic comprises bending amplitude and/or bends per minute and the bending is calculated based on an eccentricity of the objects, and the predefined resolution is the resolution at which the total error in the characteristic is at a minimum.

5. The method of claim 4 , wherein the error minimum is determined based on the error on eccentricity caused by pixelisation of the object by the image processor.

6. The method of claim 1 , wherein the predefined resolution corresponds to a smallest dimension of the object having a length between 0.5 pixels and 1.5 pixels.

7. The method of claim 1 , wherein the predefined resolution corresponds to a smallest dimension of the object having a length of 1 pixel.

8. The method of claim 1 wherein the objects are Caenorhabditis elegans.

9. The method of claim 1 further comprising preparing a sample of nematode worms:
by spraying a liquid comprising a pharmaceutical agent onto a plate comprising the nematode worms.

10. The method of claim 9 , wherein the liquid is sprayed using an aerosol nebuliser.

11. The method of claim 1 , wherein the at least one characteristic comprises bending amplitude.

12. The method of claim 1 , wherein the at least one characteristic comprises length.

13. The method of claim 1 , wherein the at least one characteristic comprises translational speed.

14. The method of claim 1 , wherein the at least one characteristic comprises paralysis rate.

15. The method of claim 1 , wherein measuring at least one characteristic comprises:
removing a background signal from captured images;
detecting the objects; and
tracking the objects across frames.

16. The method of claim 1 , wherein the imaging element has a resolution of about 9.1 Mpx, the optical system has a focal length of about 16 mm, and the field of view has a width of about 20 cm.

17. The method of claim 1 , wherein the nematode worms are provided on a 20 cm Petri dish or similar size sample holder.

18. The method of claim 1 , wherein data for around 1000-5000 nematode worms is obtained in a single screening.

Assignees

• Wren Therapeutics Ltd
• Cambridge Entpr Ltd

Inventors

• Perni Michele
• Peter Quentin Alexis Eric
• Challa Pavan Kumar
• Kartanas Tadas
• Sormanni Pietro
• Kirkegaard Julius Bier
• Vendruscolo Michele
• Dobson Christopher Martin
• Knowles Tuomas Pertti Jonathan

Classifications

• G06V20/69 Primary

  Microscopic objects, e.g. biological cells or cellular parts · CPC title

• G06V20/693 Primary

  Acquisition · CPC title

• G06V10/147

  Details of sensors, e.g. sensor lenses (fingerprint or palmprint sensors G06V40/13; vascular sensors G06V40/145; eye sensors G06V40/19) · CPC title

• G06V10/435

  Computation of moments · CPC title

• G06V20/695

  Preprocessing, e.g. image segmentation · CPC title