And thank you for making your first post on the ANA Forums!
I am not sure if I understood your question. Were you asking why there are so many repeat MRIs for GK and CK patients? If so, unlike surgery where the neurosurgeon can physically remove the tumor, the only way to know if the CK or GK was successful is by doing repeat MRIs. Often with radiation, the acoustic neuroma initially swells which may indicate that the CK or GK is making a difference. Some specialists may not want to do an MRI soon after the procedure as it may not be helpful initially as the tumor grows because of the swelling. But MRIs taken later can show that the tumor has stopped growing. In some cases, the tumor may even shrink a little. So, repeat MRIs can provide evidence that the radiation, indeed, worked.
Occasionally, the radiation did not do what it was supposed to do. Then, repeat MRIs can show that the tumors have continued to grow. At that point, the question is whether to repeat the CK or GK, or more commonly, to have surgery and physically remove the tumor. Every once in a while, the GK or CK can harden the tumor without actually killing it.
Surgery is not always successful on the first attempt, either. Sometimes the neurosurgeon is hesitant to remove the complete acoustic neuroma because it has attached itself firmly to an auditory or facial nerve. So, the neurosurgeon may elect to leave part of the tumor in place and treat it later with CK or GK rather than to completely remove the tumor and create significant issues for the pt. It is a little tricky sometimes.
What is so strange about acoustic neuromas is that everyone's journey is a little different. Some people can have an acoustic neuroma that does not grow in many years. So, they can have MRIs for several years, and there is no growth. Others can have significant growth in six months. And usually the best way to determine the growth is by repeat MRIs, not by symptoms. Symptoms can become considerably worse without a change in the size of the AN. So, repeat MRIs continue to monitor the growth or non-growth of the AN.
I am not sure that I answered your question. And I am just sharing my understanding of it. I certainly am not a physician or a specialist. I continue to try to learn more about it, just as you do, Ann.