Triage dose assessment for partial-body exposure: dicentric analysis.

Area of Science:

• Cytogenetics
• Radiation Biology
• Medical Countermeasures

Background:

• Partial-body radiation exposure necessitates specialized biodosimetry.
• Assessing non-homogeneous exposures requires a combination of clinical signs, biomarkers, and physical signals.
• The dicentric chromosome assay (DCA) is the gold standard for radiation injury biodosimetry.

Purpose of the Study:

• To summarize current knowledge on partial-body cytogenetic dose assessment.
• To propose and validate an approach for triage dose prediction in radiation mass casualties using equivalent whole-body doses.
• To address the technological gaps in dicentric analysis for mass casualty risk stratification.

Main Methods:

• Review of current knowledge on partial-body cytogenetic dose assessment.
• Proposal of a triage dose prediction model based on equivalent whole-body doses for partial-body exposures.
• In vitro simulation of partial-body irradiation by mixing irradiated and unirradiated lymphocytes.

Main Results:

• An initial screening of 20 metaphase spreads can confirm irradiation above 2 Gy.
• Increasing to 50 metaphases improves dose determination for clinical triage.
• The proposed approach shows effectiveness in simulated partial-body exposures, with potential limitations at low doses or small irradiated proportions.

Conclusions:

• The developed approach shows promise for risk-based stratification of mass casualties following partial-body radiation exposure.
• Automation of sample processing and analysis is key to increasing throughput for DCA.
• Further research is needed to fully develop and validate DCA for partial-body exposures.