Digital curation of formalin-preserved heart specimens via 3D photometric scanning: A report on recent archiving techniques and optimizations

Abstract

Background

Archived cardiac specimens are invaluable for understanding congenital heart defects (CHDs) and acquired heart disease. However, physical deterioration and declining autopsy rates limit ongoing acquisition and use. While micro-CT scanning has been used to digitally archive wax-infiltrated specimens, most cardiac specimens in our collection are wet formalin-preserved hearts, for which micro-CT is suboptimal.

Objectives

This study evaluates photogrammetry as a practical, high-fidelity digital archiving technique for wet cardiac specimens.

Methods

Eighty-four wet cardiac specimens representing a broad spectrum of CHD and other cardiac diseases were digitized using a handheld Artec Space Spider 3D scanner. Specimens were suspended via a custom apparatus to optimize surface coverage. Scan data were processed with Artec Studio and refined in Blender to generate anatomically accurate, textured 3D models. Two experienced cardiac morphologists validated the digital reconstructions against the physical specimens.

Results

Photogrammetry produced high-resolution, color-accurate 3D models closely replicating anatomical details, including complex internal structures. The custom suspension device enhanced visualization, particularly of internal chambers. Challenges included scanning smaller, darker hearts and delicate valve structures, which required manual post-processing. The digital models are accessible via a cloud-based platform for research and education.

Conclusions

Photogrammetry is a practical and effective method for digitally archiving wet cardiac specimens, preserving valuable anatomical data, and mitigating loss due to specimen degradation. This technique facilitates broader accessibility and enhances educational and clinical applications in the study of CHDs and other cardiac diseases.