Rashi's second interpretation of Braishis 27 (1) (based on the Medrash Rabbah 65 (10)) is that Isaac's eyes were weakened by the tears of the angels at the Akeidah.
Rashi speaking about the angels who visited Avrohom Braishis 18 (8) comments on the the word ויאכלו (and they ate), “they appeared as if they ate”. By this I understood that angels being spiritual beings do not eat nor shed tears.
I assume therefore that that we are not to understand the shedding of tears literally. In what figurative way are we then to understand it?