Opening the scalp
10.05pm
Paul has already marked out the area for the craniotomy. Now he cuts through Peter's skin and retracts Peter's scalp on either side of the incision, using small clips.
10.11pm
Paul continues to cut through the skin and fat layers down to the skull bone, using an electric knife that cauterises as it cuts. When he reaches the skull he clears all the blood and tissue away to prepare the site for the drilling.
10.21pm
Paul checks the tumour location against the neuronavigation system to ensure he is operating in the correct place.
Removing the skull bone disc
10.24pm
Paul starts drilling into Peter's skull. He drills two small holes in the bone either end of the section to be removed. He then slices through the bone between the two holes. This creates a neat disc that can be easily replaced after the surgery.
10.35pm
Paul removes the last few bits of tissue attached to the bone and then lifts the disc clear to reveal the white-grey dura beneath.
He then places oxidised cellulose and swabs around the edge of the exposed area to stop bleeding.
Exposing the brain
10.41pm
Crispin, the anaesthetist, explains that they are giving Peter drugs for sedation and pain relief. When they map the surface of the brain to see whether there are areas that are vulnerable to speech, he will reduce the sedation so that Peter will be more alert and able to respond to questions.
10.48pm
Paul opens the dura, the protective membrane covering the brain, by carefully cutting the tissue with surgical scissors. He places some stitches through the flap of dura tissue to keep it out of the way.
Mapping the region
10.54pm
Paul is about to start stimulating Peter's brain. As there is a risk of a seizure, they keep cold saline solution to hand. They would pour this over the brain to stop a seizure, should it occur.
10.55pm
Paul uses an electrical probe to stimulate different parts of the brain, so that they can determine whether any of the areas where the tumour is situated are involved with speech. Crispin instructs Peter to count while they stimulate. They repeat the test at different electric currents.
10.56pm
Paul detects an area where Peter's speech arrests. They test this several times. From this they determine that the right hemisphere is the dominant side of the brain controlling Peter's speech.
10.59pm
Crucially, Paul has established that there is no speech arrest over the whole area they need to operate on.
Cutting into the temporal lobe
11.02pm
Paul makes the first incision in the back of Peter's temporal lobe and prepares to dissect the tumour tissue.
Crispin keeps Peter talking all the time so that they will know immediately if his speech changes. Peter tells him that the process is quite painless.
Dissecting tumour while testing speech
11.11pm
Crispin shows Peter some images and asks him to describe them as Paul starts to delicately dissect the tumour in the upper part of the temporal lobe. Paul carefully separates tumour tissue from the surrounding normal tissue.
11.17pm
Paul uses the neuronavigation system to indicate exactly where he is working in the brain. He relies heavily on this system because he can't clearly see what is tumour tissue and what is normal brain tissue.
11.19pm
Paul explains that the tumour is about three to four centimetres in diameter. He takes it out slowly and carefully.
11.27pm
Paul frees a large section of the tumour and removes it with some forceps, leaving a large hole behind.
Completing the dissection
11.31pm
There is still quite a bit of tumour tissue deep inside the temporal lobe and Paul will try to remove as much of this as possible. He is working so deep inside the brain that the white floor of the skull is visible. Crispin continues to talk to Peter throughout the dissection.
11.47pm
Paul removes another section of tumour and completes the dissection. They can now start to close up. Paul covers the exposed sections of the brain with Surgicel to prevent bleeding.
Replacing the skull bone disc
12.01pm
Paul begins to carefully stitch the dura back together, soaking up any excess blood as he works.
12.19pm
Paul replaces the disc of skull bone and screws it back into position. Next he stitches the periosteum (the layer of tissue that covers the skull) back together.
12.26pm
Finally, Paul hands over to his registrar, Ryan, to close up Peter's scalp.
Closing up
12.35pm
The final stage of the operation is the careful stitching together of Peter's skin over his skull. This is carried out by Ryan, Paul's registrar.
