Structural changes in the crystalline lens as a function of the postmortem interval assessed with two-photon imaging...

Area of Science:

• Forensic Science
• Ophthalmology
• Biophysics

Background:

• Estimating the postmortem interval (PMI) is crucial in forensic investigations.
• Changes in the crystalline lens properties after death have been explored for PMI estimation.
• Objective and reliable methods for PMI determination are needed.

Purpose of the Study:

• To objectively evaluate temporal changes in rabbit crystalline lens organization and texture.
• To assess the potential of two-photon excitation fluorescence (TPEF) imaging microscopy for PMI estimation.
• To correlate lens structural parameters with postmortem interval.

Main Methods:

• Utilized two-photon excitation fluorescence (TPEF) imaging microscopy.
• Quantitatively analyzed lens fiber organization, delineation, and texture.
• Monitored changes in rabbit lenses at various time points postmortem (24h to 96h).

Main Results:

• Lens structure remained organized between 24h and 72h, with progressive loss of fiber delineation.
• At 96h postmortem, the lens exhibited a homogeneous pattern with minimal fiber observation.
• Lens fiber density decreased linearly with increasing PMI, approximately halving from 24h to 96h.
• Tissue texture parameters showed similar temporal changes to structural organization.

Conclusions:

• TPEF microscopy combined with quantitative analysis provides objective monitoring of postmortem lens changes.
• Observed temporal alterations in lens fiber organization and density correlate with PMI.
• This approach shows promise for improving the accuracy and objectivity of postmortem interval estimation in forensic science.