Laser ablation tomography: Rapid serial dissections, 3D modeling & quantitative analysis

Introduction

The ability to rapidly dissect, create three-dimensional models and perform morphometric analysis of insects is an indispensable tool for entomologists.   Laser Ablation Tomography, a three-dimensional analysis tool, enables researchers to study an insect’s internal physiology, visualize their interactions with other organisms and discover insights into complex regulatory pathways. 

Method 

LAT acquires three-dimensional structural data with micron resolution in opaque specimens.  The LAT process uses an ultrafast, ultraviolet pulsed laser and a rapidly-swept galvanometer scanner to continuously vaporize a thin surface layer of a sample.  The emitted autofluorescent light is directed through an optical system for filtering and imaging, creating highly contrasted, colorful stacks of images.  Stacks of images are then processed and reconstructed into a high-resolution volume rendering that can be analyzed, segmented, quantified and virtually dissected.  Depending on the sample material and its size, images can be acquired at a rate greater than ten per second. This method allows for data acquisition at unprecedented speed without the need for staining or complex preparatory procedures.

Results and Discussion 

LAT enables high-throughput characterization of morphological and anatomical traits in a wide variety of materials.  CUDA enabled libraries quickly access specimen features from captured images.  Anatomical features can be measured from two-dimensional images or combined to access three-dimensional parameters.  Studies using LAT have shown increased statistical correlations in QTL mapping studies (Burton et al. 2014).  

Conclusion 

LAT was developed to streamline phenotyping.  By automating a precise dissection and imaging process, LAT allows researchers to focus on data analysis rather than time consuming sample processes.  LAT technology stands as the only tool capable of high-speed 3D analysis that is well suited for high-throughput phenotyping, delivering cellular resolution and structural quantification. 

-  Burton AL, JM Johnson, JM Foerster, CN Hirsch, CR Buell,  SM Kaeppler, KM Brown, JP Lynch. 2014. QTL mapping and phenotypic variation for root architectural traits in maize (Zea mays L.).  Theoretical and Applied Genetics.