ILR with a gap of 186 days

Hi
could any one please guide me, i came to UK on student visa in june 2001 and continued living in UK with student visa extensions till feb 2011 then went back to my country because of the heart surgery of my father, and in August i came to UK again in visit visa, after a gap of 186 days, am i still eligible to apply for 10 years long residency rule, and does visit visa counts in 10 years rule. and can my fathers illness count as a sufficient reason to satisfy the visa officer to grant me the ILR.
thanks and waiting for the guidence.