Spontaneous Background and Procedure-Related Microscopic Findings and Common Artifacts in Ocular Tissues of Laboratory Animals in Ocular Studies

Fatal child abuse detected by systematic post-mortem fundus photograph in sudden death in infancy

In living children, the use of a wide field fundus camera such as RetCam is the gold standard practice to document retinal haemorrhages in suspected cases of abusive head trauma (AHT). In case of sudden unexpected death in infancy (SUDI), child abuse must be considered as a possible cause of death and an eye examination is required. However, no example of post-mortem fundus photograph (PMFP) of retinal haemorrhages related to AHT is yet available for clinicians.We report a SUDI case, with no external traumatic lesions or limb fractures, for which prompt PMFP showed retinal haemorrhages typical of AHT: child abuse was subsequently confirmed by the forensic investigation. We discuss why PMFP is a relevant screening test to detect retinal haemorrhages in the case of SUDI and why the use of the RetCam should be further investigated.

Assessing retinal hemorrhages with non-invasive post-mortem fundus photographs in sudden unexpected death in infancy

INTRODUCTION

In the case of sudden unexpected death in infancy (SUDI), eye examination is systematic to detect retinal hemorrhages (RH) that are a crucial hallmark for abusive head trauma (AHT). The aim of this study is to assess the ability of non-invasive post-mortem fundus photographs (PMFP) to detect RH in case of SUDI.

METHODS

Bicentric retrospective analysis of consecutive cases of SUDI under 2 years of age were managed by two French SUDI referral centers with PMFP by RetCam (Clarity Medical Systems USA). PMFP were reviewed randomly, twice, by three independent ophthalmologists blinded for clinical data.

RESULTS

Thirty cases (60 eyes) were included. Median age was 3.5 months (interquartile [1.6; 6.0]). No child died of AHT. Image quality was sufficient to assert presence or absence of RH in 50 eyes (83%). Sufficient quality rate was significantly higher when the post-mortem interval was inferior to 18 h (91%, 42/46) as opposed to over 18 h (57%, 8/14, p=0.0096). RH were found in six eyes (10%), four children (13%), with excellent inter and intra-raters' concordance (Cohen's Kappa from 0.81 [0.56-1.00] to 1.00 [1.00-1.00]).

CONCLUSION

PMFP can detect RH in case of SUDI and is a relevant systematic screening test to be carried out as soon as the deceased child arrives in the hospital. It can decrease the need of eye removal for pathological examination, but further studies are needed to define the best decision algorithm.

Presumed congenital nictitating membrane dysplasia in a Japanese white rabbit

Objective

The present report characterises a spontaneous nictitating membrane abnormality in a Japanese white rabbit.

Animal studied

The animal was a male Japanese white rabbit (Oryctolagus cuniculus, Kbs:JW, 10 weeks old at the time of purchase) that had not received any treatment. A morphological abnormality of the nictitating membrane in the animal's right eye was detected.

Procedures

Ophthalmological examinations, including slit‐lamp biomicroscopy, corneal and conjunctival staining with fluorescein and lissamine green, fundoscopy, blinking rate measurement, Schirmer's tear test, and tonometry were performed. The animal was euthanised at 15 weeks of age, and histopathological examinations of the abnormal nictitating membrane, palpebral conjunctiva, eyelid and eyeball were performed.

Results

The tip of the nictitating membrane adhered to the palpebral conjunctiva of the medial canthus. The eye and periocular tissues showed no abnormalities in the ophthalmological examinations, except for the structure of the nictitating membrane. Histopathological examination revealed that the adhered site of the nictitating membrane and the palpebral conjunctiva consisted of dense fibrous connective tissue that was consecutive to the conjunctiva adjacent to the eyelid margin and lamina propria of the nictitating membrane. The fibrous connective tissue was covered with stratified squamous epithelium.

Conclusion

Based on these results, we diagnosed this abnormal finding as congenital nictitating membrane dysplasia. This paper is the first case report describing a congenital structural abnormality of the nictitating membrane in a Japanese white rabbit.