The fluid is produced from the centre of the brain, sits in cavities called ventricles and is carried out via small exit holes. It runs down the spine and over the outer surface of the brain, gets reabsorbed back into the bloodstream and goes back to the heart as part of the blood. Production never stops. It’s like a garden fountain, constantly recycling. It’s a thing of beauty, really. Except when there is a blockage in one of the ventricles.
Hydrocephalus can be triggered by meningitis, tumours and occasionally have a genetic transmission. The majority of common or garden cases, though, come down to good old bad luck, plain and simple.
Everyone is born and for many of us the experience of delivery will prove so traumatic that the brain suffers a small bleed. Usually the blood will get reabsorbed by itself and won’t leave behind any problems. In a small number of births, however, it may cause a clot and block the ventricle.
For all its wonderful potential, the brain can be remarkably unsophisticated at times. Block or no block, it carries on producing fluid like the Magic Porridge Pot, merrily ignorant that it is literally swimming in the stuff. It’s the equivalent of pumping up an inner tube long after the tyre is hard. Hence the swelling. And the danger.
A decade ago, the family’s concerns would have been picked up before the GP was even required to give an opinion. In the UK today, the circumference of a baby’s head is measured at birth and again around the six-to-eight-week mark. It used to be the case that every time the health visitor called round, they’d measure the head and record it in the baby’s ‘little red book’. I don’t know if it was to save money or part of yet another efficiency drive – probably both – but that is no longer standard practice. If it were, the little boy’s condition could have been flagged earlier.
As it was, I had to surmise that his condition had set in after the eight-week reading, but that’s not to say it wasn’t caused at birth. The initial bleed can lead to a bit of scarring, which over time gets progressively worse until the passageway is fully obstructed.
The sad thing was, the clues were there. The baby not being able to lift his own head was the prime medical giveaway. Even before I was told this, there was a more obvious telltale sign. The baby’s little T-shirt had a scissor cut around the neck.
‘Your handiwork?’ I asked the mum.
She nodded. ‘I have to do that to all his tops. Otherwise I can’t get his head through.’
I could have cried.
It’s easy to knock the GP. I mean, babies do have large heads! And new parents do have a tendency to cry ‘doom’ at the sight of a cold. It’s really easy for us specialists in our very rarefied, highly specialized field to be able to go, ‘It’s obvious, isn’t it?’ The truth is, heads and brains happen to be my area. If someone showed me a photo of a baby’s foot and said, ‘What do you reckon to this?’ I’d go, ‘I don’t know, it looks like a foot.’ Unless it was bigger or hairier than mine, or had six toes, I’m not sure I’d know what I was looking for.
Blaming anyone is never productive. All that mattered to that little baby and his parents was whether I could do anything about it.
I’d seen it so many times. Parents besides themselves with fear. The mere fact they’d been fast-tracked to see me after weeks of seeming indifference confirmed their worst nightmares, that things with their baby were serious. But they’d known that for a while. They had been the only ones. I just hoped they weren’t blaming themselves.
‘You’re good parents,’ I told them. ‘You’re experienced parents. You trusted your instincts and you didn’t stop fighting even when you were assured there was nothing wrong. You did everything you could.’
I smiled. I wanted to put them at ease if at all possible. ‘And now,’ I said, ‘it’s my turn.’
Being told that there’s something wrong with your child’s brain must seem monstrously scary. And these two were terrified. It’s not like learning little Johnny has sprained his ankle. The goings-on inside the head are unknown to most people. Beyond their ken. Sometimes it’s beyond mine as well, but not this time. I explained about the probable little bleed, how common it is and how there was nothing they could have done to prevent it.
They took it all in, but then asked the question that everyone asks. ‘Can you help him? Can you do anything? Can you save our baby?’
As I’ve said, one thing I will never do to parents or patients is lie to them. I won’t tell them what they want to hear for the sake of it. It does no one any favours. It’s rarely the easiest path and it certainly doesn’t help me sleep at night. On this occasion, though, my candour wasn’t going to be a problem.
‘Hydrocephalus is a very serious condition and, let’s be honest, it can look very unpleasant. However, there are procedures which we have successfully performed hundreds of times. I can’t make any guarantees before we get into theatre, but there is a very strong chance that your son can be treated with this procedure.’
There was silence. There were tears. ‘Thank you, Doctor Jay, thank you.’
Don’t thank me yet – I haven’t done anything.
There are two ways to surgically reverse hydrocephalus. One procedure has been around for sixty years. It’s called a shunt – a tube that goes from head to abdomen, under the skin, and drains the excess fluid. In 50 per cent of cases further surgery is required within a couple of years. It’s also linked to other complications including infection, which brings its own dangers. However, shunts have been used for a long time and, if needed, they work. Indeed, before they were invented, hydrocephalus was very often a death sentence, or at the very least would usually ruin the child’s development.
The other option is newer, just a couple of decades old, and less invasive – if that’s possible, considering you still have to enter the brain. It entails using a small endoscope, or fibre-optic pipe, to enter the ventricle and make a new drainage hole. It’s only viable if the block is in certain locations, which for a lot of patients happens to be the case. In this instance we were fortunate. Scans provided the good news. The block was treatable from the top. We were going in.
Another name for endoscopic treatment is MIS – minimally invasive surgery. At least that is always the hope. Essentially, I’ll be inserting a tiny microscope into the middle of the baby’s brain via a keyhole incision at the top of the head. Compared to a shunt the dangers, although rare, are very real.
I can see from the scans that the blockage is in an ultra-sensitive area. Not the sort of place where one can go poking around. For a start it has exquisite pain centres. It also governs eye control. Not only could an injury here leave the baby with a lifetime of pain or numbness, it could also result in him being unable to focus properly. Destroying the blockage, therefore, is a no-no.
I wait for my anaesthetist, Karen, to give me the nod. Nothing happens until she’s convinced that the baby’s safe. ‘We’re a go,’ she says.
‘Okay,’ I reply. ‘Could we have some music?’ Once again, I have to have music – it helps me to concentrate, to focus. Not just in the operating theatre, but at my desk, in the car, when revising for exams. Basically, I would like music on whenever I am not asleep.
As the angry rhythmic chords of AC/DC’s ‘Thunderstruck’ begin to ring out around the theatre, I incise the skin, line up the drill and enter the top of the baby’s forehead. This is not the same as an adult drill. It’s finer – so fine, in fact, that it would allow me, if I wanted, to remove the shell off an uncooked chicken egg.
I demonstrated this for the start of one of the TV documentaries our department was featured in, mostly because the producers refused to believe we can do this. They brought twelve eggs in a box to give me a real sense of how much they trusted me. Fortunately, I managed to do it on the first attempt – or they would have definitely got a good shot of me covered in egg white – whisked at 75,000 rpm …
It goes to plan. I glance at Karen’s monitors. No change in the patient’s condition. Time for stage two.
The endoscope
is inserted into the expanded ventricle. Looking at my own screens I can make out the area of the blockage and the no-go zone. Just in front is another area surrounded by two really important structures: the pituitary gland (which controls the majority of hormones) and the basilar artery (a key blood-supply axis). It’s also home to the mammillary bodies, which are responsible for memory. Again, not things you want to mess with.
Peter used to say to families: ‘Imagine you’re in a room filling with water. If you can’t open the door, what do you do? Smash a hole in the window.’ I pinched that off him and use it all the time now.
Between these super important structures I can see a 2-mm gap. If I am able to poke a hole through the middle – or ‘smash the window’ – it would give the fluid a new route out of the brain. That’s the priority. Offer a diversion, break the dam and get the pressure down.
It sounds dangerous, and indeed it can be. So many things can go wrong. But I have the equipment and the experience. This operation was a huge deal back when I was a trainee and the procedure was in its relative infancy. My boss in Glasgow would set aside quite a long time and it was a bit of a palaver. As experience increased, hints and tips were collated worldwide and equipment was improved. It is now classed as ‘routine’ and can be done, from start to finish, in less than twenty minutes. Medical progress is amazing – it takes money, collegiate working around the world and often a pioneer to try what has never been tried before – but the outlook for patients just gets better and better for it.
As it is, the operation goes well, we make a small exit hole and get closed up with no worries. When I walk into the waiting room afterwards, I can see the torture behind the parents’ eyes.
‘We won’t know for certain until up to six months have passed,’ I say, ‘but all indications are that the treatment has been successful.’
‘Can we see him?’
‘Of course. Follow me.’
Five years later, that little baby is now a little boy. A little boy with a proportionate-sized head and who gets cuter every time I see him. The pressure alleviation worked. The block is still there, but so is the diversion. I see him once a year for a check-up and he’s never looked back, despite the best attempts of the Magic Porridge Pot.
If I had to guess, it’s unlikely that we’ll ever need to treat him again. The same can’t be said for the other type of hydrocephalus treatment. That’s not to say that we don’t have an extremely high rate of success, it’s just that in many cases it’s not a permanent fix. Considering what’s involved, perhaps it’s not surprising.
One of my first cases of hydrocephalus was caught during the baby girl’s six-week circumference check. In this instance, the parents had been completely unaware. They were first-timers, so everything was new and mysterious and rather frightening for them. The fact they’d suspected nothing made the diagnosis that little bit more painful to hear. The parents of the other child, as sad as they were about their baby’s condition, were expecting worse news than we actually gave them. For these guys, it came out of the blue.
Still, the baby was in no obvious discomfort and appeared to be developing well. Very quickly, though, the scans showed that there was a problem with the final point of absorption of the fluid, and not a blockage along the pathway that could be circumvented. I could smash all the windows I liked, but the fluid wouldn’t be absorbed. Which meant going to Plan B.
To say that the shunt operation is twice the procedure is quite literally true. For a start it ideally uses two surgeons. While I’m concentrating on the top end, my colleague is prepping the tummy. Between us and the nurse we have to ensure the baby is positioned in such a way that I can reach the back of her head and the registrar has access to her abdomen.
With the all-clear from the anaesthetic end of the room we begin. Firstly, I have to get through the scalp. It’s a standard ‘horseshoe’ cut – a large letter ‘U’ carved around the area I need – then carefully I peel back the skin. It’s such a small flap of a thing even compared to a ten-year-old’s, let alone to that of an adult. What’s inside is even smaller.
I drill a small hole in the bone and open up the dura – the fibrous bag around the brain. Now for the tricky part. I feed a very fine silicone tube into the fluid space in the middle of the brain. That, if you like, is the pipe that’s going to drain out the excess CSF. It needs to go straight in for 8 cm.
To aim the tube with the greatest accuracy, I have looked at the scans. These are 2D slices which I use to build up into a 3D model in my head. I then look for external landmarks – the entry into the ear, the inner and outer angles of the eye, the bridge and tip of the nose, and plot them on my internal model. With these pointers, I think about where I will place the initial incision, the entry hole in the skull and the opening onto the brain surface. Then I plot what precise direction I need to angle the tube at so that it goes through the least important brain structures possible and into the fluid spaces. Even then, it must go into the correct part of the ventricles, so that it is less likely to get blocked further down the line. It is one of the commonest procedures we do in neurosurgery, but also one that is fraught with difficulty. The list of potential problems with putting this tube into the fluid spaces is huge.
I have caused weakness on one side of the body when I missed some very small ventricles and ended up in the movement control centre. I have also caused small loss of visual field to a patient when my entry point created a small bleed. The passing of the tube, once through the outer surface of the brain that I can see, is essentially blind – there is simply no way of knowing if the tube will catch a small vessel on its way towards the ventricles. If that leads to bleeding in the brain, it can cause a stroke. If it bleeds into the ventricles, it can enable the shunt to block very rapidly or force the operation to be abandoned.
I call shunt insertion the great leveller – any neurosurgeon, of even the highest seniority, can have really major problems while inserting a shunt, though seemingly one of the simplest operations we do. It underlies the simple fact that we tell families when requesting their consent that there is no simple neurosurgery – it’s all fraught with danger and risk. ‘Now sign here, please.’
I cut a pocket under the skin I’ve peeled back. With care I can feed a metal tube into the tissue layer between the skin and the rest of the body down the baby. Think of the layer when a butcher is skinning a rabbit – there are no major vessels or structures that can be damaged, as long as I stay in the right place. It’s all done by touch and instinct. I feed with one hand and feel the impression of the tube beneath the surface. Down the back of the neck, round the side, over the shoulder bone and over the ribcage. To anyone watching it’s like a little mole burrowing just beneath the surface.
There are no maps, but I know where I mustn’t go. I have to navigate over the sheath that contains the carotid artery and the jugular vein in the neck, and the lung in the chest. One snick of those could cause more problems than I’m attempting to solve.
The ultimate destination is the abdomen, which is where my colleague has been working. He seems on track. The small incision has been made in the tummy, so he’s got access to the abdominal cavity.
‘Everything okay?’ I ask.
‘Ready when you are.’
We can both see I’m close. Even so, when the breakthrough comes, when we see the end of the tube pop out where the tummy incision has been made, it’s still a relief. It’s not a long distance in real terms – less than 30 cm – but such a journey.
The plan is for the brain fluid to be reabsorbed by the bowel. What we mustn’t do, however, is damage it in any way. The last thing we want is to open up a shuttle system for the baby’s poo to reach the brain. The infection risk would be huge. The bowel, with all its lovely contents, sits in a bag. It’s the bag we need to breach. Once the tube is inside, all the superfluous brain fluid can be fed in and dispersed naturally.
The tube I’m threading through is actually two tubes, one inside the othe
r. I remove the inner one and the actual shunt is pushed, cajoled and occasionally suctioned down through the tunnel we’ve made. When it reaches the abdomen, we remove the outer tube. We’re nearly there.
The shunt is connected to a valve. This is a mechanism of balls and springs – and precious jewels. At a certain pressure the valve will open to let the fluid escape. It’s crucial that the little door never sticks or becomes infected or causes irritation. I don’t know who discovered this, but it turns out that rubies make the ideal gateway for some designs, which is why, for many decades, most of the shunts for the world were made in Switzerland. The manufacturing companies poached lots of watchmakers to help build their shunts – almost everything was done by hand.
My colleague stitches the tummy. I make good the scalp. We’re two hours into our day and, if I say so myself, it’s been a good one so far.
I go out to meet the parents. I hate the idea of keeping people waiting for news. A single second in a hospital waiting room can seem like an eternity – as I know all too well.
The pipe inside baby Julia almost certainly saved her life. Apart from a tiny bump on her neck, which you’d really have to search for to notice it, you’d never guess there was a tube running down inside her. Today, she no longer has the original one. Man-made objects just weren’t meant to sit inside the human body forever. There’s always a risk of infection, decay and irritation from the pipe. Sometimes they just go wrong – they can block or stop working properly, just like a TV or a car. But the good news is that they’re fixable.
Julia and those like her will never be ‘cured’. They’ll always carry a little piece of silicone around inside them. But many will never really notice it. The shunt quietly works away, letting our patients live as near normal a life as possible.
CHAPTER FIFTEEN
WHAT WOULD YOU DO?
I recognized the obstetrician’s voice as soon as I picked up the phone. It was rarely good news when he called, but I couldn’t hold that against him.
Everything That Makes Us Human Page 16