Here's an example:
The five kindnesses and five mights of the right and left eyes discussed in the letter ayin are in fact the dual manifestations of the sefirah of da'at, knowledge, as taught in Kabbalah. Da'at is the power of union and communication. Providence is the power of da'at as revealed by the eyes. The power of da'at as revealed by the mouth - speech - is the more explicit form of contact and communication between individuals. Just as in the verse: "and Adam knew his wife Eve," "knew," the power of da'at, refers to the physical union of man and wife, so is "speech" idiomatically used by our Sages to refer to such union. So are we taught in the Zohar: "[the power of] da'at is concealed in the mouth."
Da'at, contact, at the level of the eyes, is the secret of the written Torah. In reading the written Torah in the synagogue service the reader must see every letter of the Torah scroll. Sometimes a "silver finger" is used to point, direct one's sight, to every word. Contact at the level of the mouth is the secret of the Oral Torah.
So, its in the Zohar and in modern Hassidic works, considered part of KBLH by Rabbi Yisrael Ba'al Shem Tov, Rabbi Yitzchak Ginsburgh's works and a concept taught within Chassidut.
If Keter is the unclosing eye of the Creator, then perhaps its inclusion is questionable. As in Malkuth, as it is the Earthly realm.
Things to ponder.