How can mri on brain miss a brain tumor when two eye docs,2 neruo, and 2neruosurgeon all say can't see tumor but there could be one starting and now have one avm in oct last year and one this june.

MRI scans: To see a tumor or AVM with MRI depends on many factors, including the size, shape, location, enhancement and secondary signs such as edema and changes in normal anatomy. A very small tumor in the right location can be easily seen, but even larger tumors cannot be seen until they change the anatomy of the rest of the brain or enhance. And very small tumors at times are not seen. Same for AVM.

Dr A Freisleben-Cook and another doctor agreed

No one: can stay completely still during an MRI. Movement artifact often masks very small findings. Some tyhings that can cause big problems are very very small and not on the "slices" of data imaged. If your symptoms are consistent with a tumor and all of the doctors treating you agree, then the real person overrules the imaging study.