Retinal Haemorrhages.

NOTE:- All names and dates have been changed apart from in extracts from medical literature.

RETINAL HAEMORRHAGES.

Consider this extract from ‘CLINICAL EXAMINATION’, page 384. “ The use of the ophthalmoscope is dealt with in Chapter 11. The difficulties of this examination in children are often considerable. To maintain the young child’s gaze in a fixed direction it is usually necessary for a second person to arrange some diversion which for the child has an element of expectancy about it. The examiner, after positioning the patient may say ,’Tell me when the torch flashes’, the torch being held in an appropriate position by a helper who may be mother or nurse, or ‘Tell me how many fingers nurse has up – how many now?,’ the nurse changing the numbers of fingers and thus maintaining the child’s attention. With younger children sedation may be necessary and in certain circumstances even a general anaesthetic may be required.

Extract from Medical Literature.

“They [Retinal haemorrages] are also reported to occur in a percentage of new born infants e.g. 14% in a study by Sezen:(……) and 20% Small(…) who found evidence of retinal haemorrhages but no evidence of intracranial injury on Magnetic Resonance Scanning subsequently. These retinal haemorrhages resolve within a short time after birth e.g. 10 days…….”.

Here is an argument stating that there is evidence of  ‘spontaneous’ retinal haemorrhages’ in a significant number of the newly born, but that these normally clear in 10 days.

It is evident from the above extract that retinal haemorrhages are commonly caused by extremely minor ‘trauma’ and are not particularly indicative of a shaking injury.

One should remember that blood circulates by surges in pressure. Restriction of the veins leading away from any part of the body cause excessive pressure surges in that part of the body.

Place an elastic band on a finger or around your wrist and this excessive pressure can be clearly felt in the extremity. This is because the elastic band only restricts the veins carrying blood away from the affected part, but the arterial blood flowing into the hand or finger is not restricted. If the restriction is long lasting then serious damage can be caused to that part of the body. If one considers a blood pressure cuff being gradually inflated over a period of weeks or months, the pressure in the veins will gradually build up until the pressure exerted by the cuff is sufficient to stop the blood flowing. If then left in this state serious damage would be caused.

In regard to retinal haemorrhages, if the veins leading from the eye are restricted, as can happen in hydrocephalus, there can be either a rapid or a gradual reduction in the blood flow. As the veins themselves require blood to sustain themselves in good working order, lack of blood flow weakens them. The areas of the eye being served by the capillaries are also damaged due to lack of blood flow. The increased pressure pulses remain but no fresh blood is being supplied. After a while the weakest veins, i.e. the capillaries in the eye, or the part being supplied, break down due to the increased pressure pulses and the poor condition.

It is evident therefore that there can be no precise time scale for the development of retinal haemorrhages.

My Own Retinal Haemorrhage.

The year following this court case I suffered a retinal haemorrhage.

I was driving out of a city centre when a black spot appeared in my right eye. This quickly changed into a black snakelike shape and then into multiple treelike branches, and finally a deep red haze that completely closed all vision in my right eye.

Luckily, having worked on the above case I immediately understood what had happened. I asked a passer-by for the location of a doctor, and within 20 minutes I was on my way to hospital by ambulance. A week later I had the first laser treatment.

Discussing the problem with the surgeon, she said that I must have an infection or I must have had a bang to my head in the last couple of days. Tests showed no signs of infections, and I certainly had no bangs to my head in the last few days.

However, I did have a severe bang to my head 6 weeks before, when I bent down to stroke our  labrador dog who jumped up to lick me at the same time, causing a collision of heads. Both of us ended up on the floor stunned for a few minutes.

For the weeks following, from dusk onwards I was aware of flashing lights in front of my right eye. These continued for the 6 weeks until the retinal haemorrhage occured. I went into hospital for laser treatment for the retinal haemorrhage about a week to 10 days later.

The surgeon was adamant that the dog incident was too early to have caused my retinal haemorrhage, but could not suggest an alternative hypothesis.

Author – Brian Williams