Imaging ATUM ultrathin section libraries with WaferMapper: a multi-scale approach to EM reconstruction of neural circuits

TLDR

ATUM can rapidly collect ultrathin sections, producing petabyte‑scale image libraries, yet current imaging throughput remains limited to about 1 TB per day. The authors developed WaferMapper to enable multi‑resolution mapping and selective high‑resolution imaging of regions within an ATUM section library. WaferMapper automatically selects corresponding regions across thousands of sections, directs imaging at chosen resolutions, and supports expansion, re‑imaging, or alternate imaging conditions. With WaferMapper, the entire library can be mapped at low resolution and specific anatomical landmarks can be targeted for high‑resolution imaging.

Abstract

The automated tape-collecting ultramicrotome (ATUM) makes it possible to collect large numbers of ultrathin sections quickly—the equivalent of a petabyte of high resolution images each day. However, even high throughput image acquisition strategies generate images far more slowly (at present ~1 terabyte per day). We therefore developed WaferMapper, a software package that takes a multi-resolution approach to mapping and imaging select regions within a library of ultrathin sections. This automated method selects and directs imaging of corresponding regions within each section of an ultrathin section library that may contain many thousands of sections. Using WaferMapper, it is possible to map all the sections at low resolution and target multiple points of interest for high resolution imaging based on anatomical landmarks. The program can also be used to expand previously imaged regions, acquire data under different imaging conditions, or re-image after additional tissue treatments.