The document describes a new tomographic imaging technique called Light-CT that allows for fast, non-invasive 3D imaging of the C. Elegans worm. Worms are anesthetized, encapsulated in a gel, and placed between a slide and coverslip before being imaged with the Light-CT scanner at a resolution of 1um. The full 3D imaging of the worm can be acquired in about 2 minutes, allowing identification of internal anatomy like the pharynx, isthmus, and gonad arms. Light-CT provides optical sectioning and volumetric imaging capabilities superior to standard microscopy.

1. Tomographic non-invasive imaging of C. Elegans worm: LLTech Light-CT™ scannerSample preparation: worms are anesthetized and encapsulated in a gel

2. a gel layer is placed between slide and coverslip

3. the sample is imaged using standard Light-CT scanner procedureImaging:3Dtomographic resolution: ≈ 1µm, non invasive, non destructive

4. 3D acquisition of whole worm: 2minutes (about 60 images, thickness 1µm), allowing fast 3D optical biopsycoverslipEncapsulated wormsMicroscope slide

5. Light-CT allows fast identification of anatomy – worm 1Image plane 1 @ 15µm depthImage plane 2 @ 30µm depth800µm800µmCorpuspharynxIsthmusPosterior bulbExcretory canalspermatheca1vulvaeggsovocytesspermatheca2gonad armintestineovocytes

6. Light-CT allows fast identification of anatomy – worm 2Image plane 1 @ 15µm depthImage plane 2 @ 30µm depth800µm800µmovocytesintestineBody wall - cuticlegonad armuterus

7. Light-CT allows full volumetric imaging in a few minutesLight-CT image: allows fine separation of structuresStandard microscope imageOptical sectioning:1µm thickness imageLight-CT images at different depths reveal fine structural details

8. Light-CT allows fast, precise 3D rendering and volume exploration

9. Images with 40x objectiveMuch higherresolution