Pupil sizes of bodies with variant post-mortem intervals.

Abstract

Objective : To determine the relationship between the pupil sizes and the post- mortem intervals in order to estimate the time of death.

Setting : Chulalongkorn Forensics Center, Faculty of Medicine, Chulalongkorn University

Research design : Prospective descriptive study

Materials and Methods : The pupil sizes of the bodies are measured by using pupil gauge with 2, 3, 4, 5, 6, 7, 8 and 9 millimeters scale.

Results : Pupils of 171 bodies (141 males and 30 females) with age ranging from 20 to 70 years old are measured by using pupil gauge in particular post-mortem intervals. The average pupil size at the time of death of less than 2 hours, 2 to 4 hours, 4 to 8 hours, 8 to 12 hours and 12 to 24 hours are 4.8, 5.6, 4.8, 4.3 and 4.0 millimeters, respectively. A statistically significant (p < 0.05) between pupil sizes at variant post-mortem intervals are observed, except the pupil size in the time of death that was less than 2 hours and 4 to 8 hours.

Conclusions : The estimation of post-mortem intervals by measurement of the pupil diameters can be done easily at the crime scene, it takes low cost and does not disturb the body. A combination of these methods with examinations of rigor mortis and livor mortis will help the physicians estimate the time of death more precisely.