How Asa sees

We got three new pieces of information this week – about Asa’s vision, the state of the tumours in his eyes, and the genetic basis of his condition.

1. How Asa sees

On Tuesday afternoon, an orthoptist tested Asa’s vision. She waved toys in front of him to assess how well he could track moving targets, and used a set of cards with images of varying clarity printed either on the left or right, or top or bottom, to see whether he could discriminate between image and blank space.

Taken together with what we know from other examinations, the results suggest that Asa’s vision is worse than we’d supposed based on his everyday behavior.

In the right eye he probably has good vision only on the periphery, and in the left eye his vision is probably blurry.

The reason is that the right eye has a centrally located tumour, and in the left eye – while the tumours are located lower down, affording a decent visual field – what he sees is probably blurred on account of retinal detachment.

Squint with your left eye and hold your fist about 6 inches in front of your right eye. That’s probably roughly what Asa can see.

But now imagine that this is all you’ve ever been able to see. That this is what the world has always looked like.

Then this way of seeing ceases to seem so poor.

By combining two deficient signals, and using them to the max, Asa seems to achieve something equivalent to what one good eye could do.

His ability to navigate – walking around, exploring – is good on account of the peripheral vision in his right eye, while his ability to manipulate things directly in front of him, make eye contact and so on, relies mainly on the central vision in his left eye.

He carries this off so well that we’d come to doubt that he was really visually impaired.

2. State of the tumours

The next morning Asa’s eyes were examined under general anaesthetic.

In the left eye, there was no change since last time. But two small tumours in the right eye have shown new growth over the past 6 weeks.

These were treated with cryotherapy – a freezing probe directed precisely at these spots. The cryo needs repeating to be effective, so Asa will be back for more in 3 weeks time.

3. Genetics

Results of the genetic test confirm that Asa has a change in the gene that regulates retina development. It's a strong change – a “fully penetrant mutation” – of the sort that almost always results in bilateral retinoblastoma.

This is what we expected.

The good news is that neighbouring genes are OK.  Asa’s not at risk of any other developmental abnormality.

Blood was also taken from Selam and me for testing, to check whether we have changes in our RB genes that could lead to a risk of retinoblastoma in other children we might have in future. These results will take a couple of months.

Round up

What we’ve learned will take a bit of digesting. But we have a much clearer understanding now of the state of Asa’s eyes. What comes with this is a heightened concern that he should retain what he has.

If there’s deterioration in either the peripheral vision in his right eye or the central vision in his left, he will likely end up much more compromised.

That said, some things we knew already bear repeating:

With the monitoring and treatment that Asa will receive over the coming years, this disease is very unlikely to endanger his life. The worst case scenario is blindness.

The period of the greatest danger in terms of tumour activity is from birth to 3 years. From 4-5 years, there’s a continued risk. After 5 years the risk decreases greatly.

Until that window closes, we won’t know what the long-term prognosis is, in terms of his sight. From month to month there may be changes, and it’s unpredictable. So we have to keep watching, and respond to problems as they arise.

The end of chemo

Asa's last dose of chemo was given 6 weeks ago, and he's now largely recovered from the side effects -- he's comfortable, his appetite has returned, and little hairs are sprouting all over his scalp.

I’ve been remiss in sharing this news, in part because as soon as the chemo finished, Asa developed chicken-pox, and we were thrown back into emergency mode.

He broke out in spots on May 28, and at that point, his immune system was still compromised, and we were afraid the chicken-pox was going to be unusually severe.

On doctors' advice, Asa was kept in hospital for 10 days on IV Aciclovir, a drug that slows the reproduction of the virus. 

In the event, the chicken-pox was mild, and the spots didn't seem to cause him much pain.

There was still some systemic imbalance that needed to be sorted out afterwards: Until last week, his potassium levels were still low, and we continued giving him supplements through his NG tube.

But by last Saturday, he had normalized, and we pulled out the NG tube.

Asa, a few days before his NG tube was removed.

Perhaps that would have been the appropriate time to have thrown a party.

It's difficult to describe what a relief it is not to be giving Asa medicine, after 5 months when he rarely went without at least one or two doses of some drug or another each day.

What next?

Many people would like to know whether the chemo worked. 

We may have partial answers within the next couple of days.  

This afternoon we travel to London, where Asa will have two eye exams -- one a vision test at which he's presented with various stimuli and the doctor tries to evaluate how well he sees; and another, tomorrow, when his eyes are examined while he's under anaesthetic.

We have to think about these tests not as the final exams after chemo, but as the first after chemo. 

The reason is that, even if the tumours appear quiescent, there's still a chance they could reactivate in future.

Asa will need exams under anaesthetic roughly on a monthly basis from now until he's about 5 years old (when the risk of new tumour activity decreases).

The prognosis we'll get tomorrow, then, probably won't be for the long term, but "for now".

Thank you!

This is a good time to acknowledge our gratitude for the people and institutions that have helped us get through the last 5 months.  A short and certainly not exhaustive list must include:

1.    Selam – who first noticed the signs of retinoblastoma, and sounded the alarm, and who has done more than anyone to bring Asa this far

2.     The National Health Service – which has given us access to excellent medical care, from specialists to community nurses who visit our home every week

3.    The grandparents, especially Kay and Clive, who have provided support to us all throughout

4.    Other friends and family who have kept our spirits up through the difficult times.

Thank you all!

A few words from Asa

It’s partly a testament to the contributions of all these people, and partly due to his own resilience, that Asa's been developing normally though all of this.

Right now he has a receptive vocabulary larger than we probably realise. He knows the words -- in Amharic or English or babytalk -- for breast ("tuut"), blender ("Nnnnngggg!"), hand-washing ("water-play"), piggy-back ("che-che"), "up", and "down". 

The comprehensible utterances he produces are limited to daddy ("Adada"), mummy ("Mama", which for some reason he says much less commonly), and "There!"

Beyond this, he is a great mimic, imitating sounds -- the noises of the washing machine, cars, coughs and sneezes, and the melodies of familiar songs ("This old man…" and "Twinkle, twinkle, little star") -- and actions like eating, scrubbing, and sweeping: things he’s seen us do a lot.

For a long time Asa was a slacker in terms of chewing his food, but he's making progress on that front now, and in the last few days he's chewed and swallowed bread and raisins.  Biltong next.