Orphaned disks in vSphere 5.5 - ESXi 5.1

Hi

I am trying to find the root cause of resolving this orphaned disks in my environment.

my environment consists of VC 5.5 with ESXi 5.1 Hosts and running vCheck report everyday is showing lots of Orphaned disks. so far, i checked on different forums and nothing is related to my situation, as those orphaned disks are not due to any vmware snapshots and there are no delta files / vmdks but looks like they are all left over VMDKs of different sizes and some are of 0 KB sizes as well. i also checked that most of these are not in use at all and there is no locks for these VMDKs / VMs related to these.

Please advise where to check and how do i identify the root cause of this.

Thanks