RT Journal Article SR Electronic T1 Acute visual loss without concurrent headaches due to ultrasound-negative, biopsy-proven giant cell arteritis JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP s58 OP s58 DO 10.7861/clinmed.20-2-s58 VO 20 IS Suppl 2 A1 Ruchir Singh A1 Tharshini Rajakulenthiran A1 Sethuge Silva A1 Roshan Amarasena YR 2020 UL http://www.rcpjournals.org/content/20/Suppl_2/s58.abstract