Non-invasive visualisation and volume estimation of maggot masses using computed tomography scanning

Area of Science:

• Forensic Entomology
• Medical Imaging
• Developmental Biology

Background:

• Maggot mass heating significantly impacts insect development, affecting growth rates.
• Accurate maggot mass volume measurement is crucial for forensic entomology, but traditional methods are invasive and difficult.
• Existing maggot growth rate models lack precision due to unquantified thermal effects from maggot masses.

Purpose of the Study:

• To develop and validate a non-invasive method for measuring maggot mass volume using computed tomography (CT) scanning.
• To establish reliable protocols for volumetric analysis of maggot masses from CT data.
• To assess the reliability and applicability of CT-based measurements in forensic casework.

Main Methods:

• Computed tomography (CT) scanning was employed to visualize and measure maggot masses.
• A standardized set of rules was developed for volumetric analysis of maggot masses using CT imaging software.
• Inter-rater reliability was assessed using measurements from four independent observers ('judges') on various maggot masses.

Main Results:

• CT scanning successfully visualized and measured maggot mass volumes non-invasively.
• The established CT volumetric analysis protocol demonstrated excellent inter-rater reliability (Intraclass Correlation Coefficient > 0.95).
• High reliability was consistent across different maggot mass sizes and types, including experimental and naturally occurring masses on human remains.

Conclusions:

• Computed tomography (CT) scanning provides a reliable and non-invasive method for determining maggot mass volume.
• This technique enhances the accuracy of forensic entomology by enabling better estimation of maggot developmental temperatures.
• The routine reporting of entomological features from mortuary CT scans in forensic casework is now feasible and implemented.