On Wednesday the 1st of May we returned to Melbourne again for Isla’s 16th EUA. The EUA went well, there were no new tumours and everything looked the same as last month. They showed us the retcam images again today and compared them to previous months. They showed us how the tumour mainly looks inert and ‘coral like’, but there is a small ‘smooth, fleshy cap’ on top of it, which still looks active and has a good blood supply. The doctors will continue to keep a close eye on it, with the view to attempt intra-arterial chemo again at some stage in the future. However, they did mentioned if things are still looking the same in the next 2-4 months we may be able to stretch our EUAs out to every 2 months.
We had a meeting the following morning with one of the interventional radiologists to discuss the intra-arterial chemo alternative route options in more detail. This meeting came about from my question in April regarding the risks of attempting intra-arterial chemo using the vertebral route. Since the carotid route wasn’t working and there are clear risks with ballooning off the internal carotid artery, I basically saw no reason not to attempt the vertebral artery route and wasn’t sure if there were some risks associated with this method that we weren’t aware of. The Dr explained the anatomy again, which we knew (sharp angles, difficult to catheterise) and I asked him about the risks of this route and basically, why hadn’t they tried it already.
As I suspected/was hoping, it was basically just that they had never done it this way before and were not as confident in doing it a way that they weren’t familiar with. The posterior (vertebral) route is favoured by the French (and I think also the Japanese) and the anterior (carotid) route is favoured by the British. The Australian radiologists performing the procedure were trained by the British, so that’s the method they know. Each method has its pros and cons, but basically it’s just what they are more confident and familiar with. He said the main reason the British like the anterior route is because it is slightly shorter and straighter, therefore generally more simple to catheterise. However, in Isla’s case it was obviously not simple to catheterise, and they were more than happy to attempt the posterior route in the hope that it may work better for her.
However, he did also mention that the issue was not solely surrounding the sharp angle to get IN to the ophthalmic artery; once in the ophthalmic artery there are bones in the way, which make that artery itself very difficult to navigate. So even if the posterior route helps with getting into the ophthalmic artery, it’s not necessarily smooth sailing from there. We weren’t aware of that difficulty and that slightly deflated our hope that the posterior route would be successful for Isla, but the chat with him was certainly interesting and useful.
Since that meeting took all of about 10 minutes and we had a flight scheduled for the afternoon, we had half a day to kill, so it was zoo time!
Melbourne Zoo
© Alison Davey 2021