[NTG-context] How to add entire chapter's page ranger for index entry?

I am adding items to an index simply using `\index{word}`. There are a few cases where instead of printing just the page number where `\index{word}` is placed, I need the entire page range for that chapter to be displayed. For instance, if Chapter 3 spans page 22-50, and I place `\index{word}` in Chapter 3, I need the index to display "word 22-50", but only for that entry...not for all index entries. How to add entire chapter's page ranger for index entry? --Joel