Your report is confusing. You note a previously diagnosed isthmic spondylolisthesis at L5-S1 with a 7mm slip. You then note a cervical MRI with findings. I assume this is for a new pain unrelated to your lumbar disorder.
In regards to your cervical spine, you have an enlarged spinal canal and foramen magnum (hole in the skull where the spinal cord exits). This is associated with Klippel Feil syndrome (see website) a congential fusion of C4-5. Klippel Feil syndrome along with the enlarged canal is typically assocated with some genetic anomolies. As long as the cervical spine is stable, this should lead to no significant concerns in the short term.
Dr. Corenman