Diagnosing Subtle Brain Injury

The recent personal injury case of van Wees v (1) Karkour (2) Walsh, contains some interesting discussion of the medicine behind claims for subtle brain injuries. The issue arose as follows: the Claimant argued that her injury consisted of organic brain damage therefore it was likely to be permanent (leading to a claim for ongoing losses). The Defendant argued either that she was consciously exaggerating her symptoms or that her continuing injury was down to psychological factors from which she was likely to recover.

A particularly interesting feature of the case was that the Claimant was and remained highly intelligent. The effect of the accident (if anything) was that it had taken her edge off. She was more easily fatigued and found it harder to concentrate. The case stands as testament to the fact that a minor brain injury that reduces a Claimant’s intellectual capacity slightly can found a substantial claim in damages.

The key diagnostic indicator in subtle brain injury cases is Post Traumatic Amnesia (PTA). In van Wees the Judge carefully defined PTA. The crucial point is that it is not a total lack of memory. Rather, it is characterised by “islands of memory, punctuating periods of loss of memory”. It begins at the accident and lasts until the return of normal complete memory.

Medical experts use the duration of PTA as a guide to the severity of a head injury: PTA of less than one hour indicates mild head injury; PTA of less than one day equals moderate head injury; more than one day indicates severe head injury and more than one week being very severe. The categorisation is important because only a severe head injury is likely to lead to ongoing symptoms. The Judge accepted these guidelines as the product of medical experience. However, he described them as “an estimation (no more than that)”. Thus they were regarded as a relevant factor in assessing the severity of injury, but not conclusive.

The only way of assessing PTA is by medical experts taking a history from the Claimant. It is particularly important to distinguish genuine recall from reconstruction (things the Claimant knows happened because others have told them). The Claimant emphasised that the history needed to be taken carefully and sensitively. The Judge held that there is no magic in the process of obtaining a PTA history. Indeed he refused to criticise the Defendant’s expert for only taking ten minutes over it.

The Judge found that the Claimant had suffered post traumatic amnesia for around 24 hours. He reached this conclusion by scrutinising the Claimant’s various accounts of the accident. She consistently said that she had no recollection of the accident. She remembered: vomiting in the ambulance; being moved around the hospital on a trolley; being checked upon once in hospital and flagging down a taxi outside hospital (but not her actual discharge). This suggested she was still suffering PTA at the time of her discharge from hospital. Accordingly, the Judge found that the Claimant had suffered an injury of moderate severity which caused ongoing brain damage.

AIDAN ELLIS