A 32-year-old man presents with a 6 week history of headaches. He states that the headaches started after he lifted a heavy object in his yard and felt a minor pop in his mid back. The headaches are worse with standing and somewhat relieved with bedrest. He denies other symptoms. His primary care physician ordered an MRI of the brain, which revealed a pituitary mass. The patient was referred for surgical resection of the pituitary mass.

His general physical and neurological examinations are normal. Neuroendocrine lab work is entirely normal.

What is the likely diagnosis? What (if any) additional diagnostic test would you perform? What treatment would you recommend?