|Year : 1979 | Volume
| Issue : 4 | Page : 208-209
Estimation of the time of death by papillary behaviour at different temperatures
DB Chandra, TN Agarwal, Vipin Bihari
M.D. Eye Hospital, Allahabad, India
D B Chandra
State Institute of Ophthalmology, Allahabad
Source of Support: None, Conflict of Interest: None
|How to cite this article:|
Chandra D B, Agarwal T N, Bihari V. Estimation of the time of death by papillary behaviour at different temperatures. Indian J Ophthalmol 1979;27:208-9
|How to cite this URL:|
Chandra D B, Agarwal T N, Bihari V. Estimation of the time of death by papillary behaviour at different temperatures. Indian J Ophthalmol [serial online] 1979 [cited 2020 Aug 13];27:208-9. Available from: http://www.ijo.in/text.asp?1979/27/4/208/32632
Supravital reactions which occur during the period called intermediate life i.e. from moment of clinical death (state of the body showing complete cessation of the functions of the brain, heart and lungs) to biological death (death of the tissues and cells individually, which take place sometime after the stoppage of the vital functions), has been established of medicolegal importance by various workers. The eye ball is specially suitable for the observation of such phenomenon. However, the role of environmental factorse, specially the temperature in determing the psot mortem pupillary phenomena during this period has not be clearly understood.
The present study entails the role of different temperature in the post mortem phenomenon of continued papillary movement, as well as the duration of intermediate life.
| Materials and Methods|| |
In the present study, 18 random bred pigmented rabbits with 36 eyes weighing between 2 to 2.5 Kgs. were studied. In all rabbits euthanaesia was induced by intracardiac injection of 8 ml. saturated magnesium sulphate solution so that immediately after cessation of respiratory and circulatory (heart) sounds, the phase of clinical death ensued. For different temperature assessments, the experimental animals were categorised in three groups, as follows:
Size of the pupils were measured by a special callipers at one hourly interval till maximal dilatation was noticed.
Miotic used was 0.5% prostagmine solution (eserine). The miotic was injected into the anterior chamber to assess the stage of irreversible maximal dilatation. During the period of continued viablity of the pupillary phenomenon, miotic injection caused temporary miosis of variable sizes. The stage of irreversibility was confirmed by lack of any pupillary response to miotic. For introducing the miotic into anterior chamber of the eye insulin syringe with a very fine needle was used. The needle was inserted at limbus, parallel to anterior plane of the surface of iris to avoid any injury. The quantity of miotic injected was 0.1 ml.
| Observations and Comments|| |
Premortem pupillary size under experimental illumination measured to an average of 3 mm. in diameter.
Immediately after sacrificing the animal the pupils dilated to an average of 12 mm. diameter in size. After an interval of 2 to 3 minutes pupil constricted back to 2 to 2.5 mm. in size.
During assessment of pupillary size at different intervals under different temperatures, pupils were found vertically oval initially and became spherical in shape later.
Environmental temperature had a definite effect on the maximum size of the pupil. The time when this size was attained and the duration of the response to miotics are shown in [Table - 1].
Pupillary dilatation of rabbits in different groups varied by not more than ±0.5 mm. in size. At 4°C maximum dilatation of pupil reached 9 mm in 26 hours. At 25° C it was 8.5 mm in 22 hours and at 40° C it was 10 mm in 16 hours. [Table - 2]. It was observed that shape of pupils were vertically oval i.e. vertical diameter was greater than the horizontal diameter but later the shape became spherical. In contrast one rabbit in group III `A' showed horizontally oval shape initially later becoming spherical.
The papillary reaction after introducing miotics was observed in subgroup `B' of all the groups. Miotics was introduced only after full dilatation of pupils were achieved in rabbits at different temperatures. All the rabbits showed response to miotic except one in group III `B'.
In most of the eyes, the response to miotic was quicker. Only sometimes, it occured after 15 to 20 seconds. On an average, the pupil constriction induced by the miotic was 3-4 mm. Occasionally the constriction was very marked (pin point pupils.)
In the present study, we observed supravital reaction of pupils at different temperatures revealing interesting results. We find the post mortem interval to be 26 hrs. at 4°C, 22 hrs. at 25°C and 16 hours at 40°C, maximal periods in which positive reactions of pupils can be obtained in experimental rabbits. It will thus be seen that temperature has a very important role in prolonging or decreasing the period of Intermediate life.
1) Examination of supravital reactions of the pupils may be useful in medicolegal practice. For more accurate estimates further analysis on a large sample of human deaths is needed.
2) A post-mortem interval of 26 hours at 4° C, 22 hrs. at 25°C and 16 hrs at 40° C seems to be the maximal period in which positive reactions of pupils can be obtained in experimental rabbits.
3) Temperature has an important role in prolonging or decreasing intermediate life.
[Table - 1], [Table - 2]