Man presents with right-sided headaches, ocular pain and vesicular rash

A 64-year-old man presented to the emergency department at Lahey Hospital with a 6-day history of right-sided headaches, right ocular pain and vesicular rash.
He had a medical history of psoriatic arthritis on Humira (adalimumab, AbbVie), diabetes type 2 with peripheral neuropathy and left toe amputation, cirrhosis secondary to hepatitis C, lumbar disc degeneration with multiple surgeries, obesity, hyperlipidemia, and polysubstance abuse and active tobacco use (10-pack years). He attributed the pain to a recent decrease in oxycodone for his chronic back pain, which subjectively improved with