Map spatial index table to base table?

I've got a segment that has grown unexpectedly large.  One segment has 7086 extents in the a single data file. 

Select owner, segment_name, sum(1)
  From dba_extents
Where file_id=202
   And segment_name=’SYS_LOB0022735055C00002$$’
Group by owner, segment_name;

OWNER  SEGMENT_NAME  SUM(1)
proj1  SYS_LOB0022735055C00002$$ 7086

Select table_name, column_name
  From dba_lobs
Where owner=’proj1’
   and segment_name=’SYS_LOB0022735055C00002$$’;

TABLE_NAME  COLUMN_NAME
MDXT_46D32F$BKTS  MBRCOORDS

I know the segment and table are part of a spatial index.  But, how do I find out what data table they apply to?  (This database has thousands of tables with spatial columns.  I can’t just browse for it.)