1. Are there distinguishing retinal features for abusive and non-abusive head injuries in children?
C. Morris, S. Maguire, A. M. Kemp, D. M. Farewell, P.O. Watts
Cardiff University
Presenter: Charlotte Morris
BIPOSA conference, Bournemouth 2012.
Hello my name is charlotte morris, I am a 4th yr medical student at CU. I am here to present to you my BSC dissertation project – title.
I have not yet completed my ophthalmology module so please forgive me for any lapses in knowledge in this area. Mr P. Watts is present, and will be happy to answer any ophthalmology related questions.

2. background
Abusive head trauma (AHT) is the most common cause of death in abused children
Diagnosis is difficult
Maguire et al. proposed a statistical model to estimate the probability of AHT using 6 features (head and neck bruising, long bone fracture, rib fracture, seizure, apnoea and retinal haemorrhage)
This study aimed to validate the model and further refine retinal features associated with AHT.
This presentation discusses the further refined retinal features
Aht is the most common cause of death in children who are abused, and its prevalence is estimated at 20-24/100,000. Evidence suggests that AHT is a difficult diagnosis for a clinical team to reach, up to 80% of cases may be missed. Certain features are recognised as being significantly associated with AHT, and a statistical model proposed by Maguier et al aimed to use these features to create a valid estimate of probability to underpin a clinical diagnosis of AHT. Retinal haemorrhage has been associated with AHT in several widescale studies, this study aimed to validate the statistical model on a novel dataset and further refine the retinal features associated with AHT. This talk concentrates on the retinal features.

3. Ascertainment of cases
Neuroimaging database every child aged <36 months who underwent neuroimaging at University Hospital of Wales from Jan Jan 2012.
Cases were included if:
Aged less than 36 months
Intracranial Injury (Subdural Haemorrhage, Sub Arachnoid Haemorrhage, Cerebral Oedema, Hypoxic Ischaemic Injury, Skull Fracture, Diffuse Axonal Injury, Extra-Dural Haemorrhage, Focal Parenchymal Injury) present at neuroimagaing*
*Congenital abnormalities, space occupying lesions, infective cause and hydrocephalus cases were excluded
The nuroimaging database from UHW was obtained for children aged less than 36 months, who underwent neuroimaging between jan 2007-jan Those children who had positive neuroimaging were included in the study, unless this was due to congenital abnormalites, sol, infective cause or hydrocepahlus. The NHS number was noted and these case-notes were obtained t extract further data. Every effort was made to ensure all possible cases were captured, as well as the neuroimaging database, the paedicatric ICU database was checked, a list of all children with investigated head injuries was obtained from the child protection nurse, and the weekly paediatric clinical meeting was attended.

4. Ophthalmological methods
Indirect ophthalmology by ophthalmologist at SpR Grade or above*
RETCAM images identified where possible
Dilation recorded in notes
THIS SLIDE REQUIRES MR WATTS INPUT:
WHAT TYPE OF RETCAM?

5. results 78 potential cases identified 14 notes unobtainable
3 elsewhere in Wales, 7 in legal department, 4 RIP-with coroner
Total included
64 cases
(82%)
AHT 21cases
nAHT
(accidental)
43 cases
64 cases
21AHT
Examined by specialist ophthalomologist 20
(98%)
No eye examination 1
(2%)
43 nAHT
Examined by specialist ophthalmologist 27
(64%)
No eye examination recorded 16
(37%)
This slide does not look like this on the screen. The first flow chart fades into the second!
From the database 78 cases were identified, 14 sets of notes were unavailable leaving 64 for analysis. Of these 21 were abusive head injuries. For cases to be deemed “abuse” a strategy meeting, case conference or legal proceedings must have deemed the injury abusive. This is the highest level of proof worked to in this area of research. The remaining 43 cases were deemed accidental as they were witnessed by an independent observer, were a motor vehicle collision, or were deemed accidental after strategy meeting with the clinical team.
Looking now at the ophthalmological examinations received:
For the AHT group 98% were examined by a ophthalmologist at SpR grade or above, using indirect methods. Compare this to the nAHT group, where 65% were examined by a specialist ophthalmologist at SpR grade or above.

6. Graph Showing number of Children in Each Group with specific retinal features
Of those who had eye examination, 19 of the 21 abuse cases had retinal haemorrhage, compared to 2/43 for the nAHT cases. Bilaterality and retinoschisis were not significant indicators of whether an injury was AHT or nAHT. However tntc rh was significsantly associated with AHT with a p value of <0.04. other investigated features were location and layer of retinal haemorrhage with posterior pole being strogly but not significantyl associated, and multilayered not being associated.

7. limitations Small study sample size Retrospective Detection bias
Type II error
Retrospective
Detection bias
nAHT less likely to be examined
This study was conducted on a small sample of children, due to the fairly low prevalence of AHT in children. However, despite this there are some significant results, and there are other studies in the field of comparable size.
The retrospective nature of the study inevitably led to difficulties in data collection, meaning that missing data was a problem. This was more of an issue with the other fields of data, such as fractures, rather than the ophthalmological features.
As is common in this field of research detection bias may have been an issue – those with AHT were more likely to be examined than those with nAHT meaning rh may have been found more commonly in this group.

8. conclusions Results should be interpreted with caution
Well described association of retinal haemorrhage with AHT supported by this data
Too Numerous to Count RH was significantly associated with AHT
Retinoschisis, bilaterality, location at posterior pole or multilayer were not significantly associated with AHT
Further retinal haemorrhage detail could be useful for identifying cases of AHT.
DR MAGUIRE SUGGESTED YOUR INPUT FOR THE CONCLUSIONS: WHICH AREA IS BEST TO FOCUS ON?

9. acknowledgements Mrs Diane Nuttall,
Research Nurse Cardiff and Vale UHB