Page CTR - Clicks Turnover Rate (May be), Means percentage of clicks you got on total page impressions. For Example you got 30 clicks out of 1000 page impressions means your CTR - 3.00%.
Page eCPM - Means earnings for 1000 page impressions. If you got $ 1.50/- earnings out of 1000 impressions (what ever may be the clicks), your Page eCPM = $ 1.50/-
I think I have clarified your doubts.
RK - Some thing special