There is no specific difference between grade 1 and grade 2 meningioma in terms of clinical symptoms, but there is a clear difference at the cellular level. In general, meningioma grade 1 is caused by abnormal proliferation of normal cells, and there is no significant difference in the nucleus, mitochondria, and other conditions from a cellular point of view. In the case of meningioma II, the nucleus and mitochondria microscopic structures are abnormal, such as increased nuclear schizophrenia, which means that the process of proliferation and differentiation is more likely to occur, and differentiation often does not mean that it goes to a good place, but may also go to a worse place. Just like the population, all good people, and some here and there gradually appear one or two bad people, and then more and more bad people, it will form the difference between the first and second level.