User blog comment:Xilinoc/Ch. 616 - Mimihagi-sama/@comment-24031741-20150219195423/@comment-26091912-20150221062015

I never said Aizen lost his Reiryoku, I said that he lost Kyoka Suigetsu along with his Hogyoku form(s). During his clash with Ichigo, he commented about how their Zanpakuto fused with their right arm, and after he regenerated it faded into nothing. According to Mayuri; a Zanpakuto that's broken in sealed state or shikai can be fixed, as long as the hilt remains intact. Since Kyoka Suigetsu was destroyed completely, it can never return.

Also, perception of time (chronoception) is not based on any sensory organ, it's a psychological phenomena. Aizen said Complete Hypnosis only affects those who can see, therefore someone who is blind (e.g. Tousen) is immune to it. So when Yhwach talked about Aizen "confusing his perception of time", it simply means he lost track of time in the few mintutes the two conversed. Aizen is after all, a master manipulator and tactician.