Hello Marijke,
If you're outside the Buckinghamshire NHS PCT area then Mr. McLaren usually ensures that 'out of area' patients are seen by him personally, tested and scanned on one visit and then operated on on the next visit. He recognises that people who live 'out of area' can't afford the time or the money involved in multiple trips and so he keeps it down to a minimum of 2. If I remember rightly, I had two letters - one for the ultrasound appointment and one for the sestamibi scan. I was told by Mr. McLaren to call his secretary to ensure that I was pencilled in for a consult with him on the day so we could discus the scans/bloods and surgery. I didn't have a fixed time for the consult with him as it was a busy day with scans and all, so it's a case of fitting him in between scans.
It might be best just to give Mr. McLaren's secretary a call and ensure everything is in place for the day, she will tell you how to go on. His secretary is very pleasant to deal with and she'll help you all she can and if she can't she'll check with Mr. Mc about what to do.
Just to put your mind at rest, nothing to worry about on the scans/pre-op tests etc, everyone is extremely helpful and pleasant and the scans themselves are not in the slightest bit scary. The sestamibi scan can be boring as you have to lay there for 40min (twice) but I just drifted off in a daydream, my only gripe was the sestamibi scan room and in fact the whole hospital was very warm!

If you need Mr. McLaren's secretaries number just let me know. All the best for the 10th give my regards to Mr. McLaren.
Best wishes,
Simon