Medical Eponyms Letter O

282. Occam’s razor is described in 14th century - “plurality must not be posited without necessity -” in other words - parsimony in diagnosis.
283. Oliver’s sign is in aortic aneurysm - pulsation of aorta felt through cricoid cartilage when chin is elevated.
284. Oppenheim’s sign is involuntary dorsiflexion of the toes when stroking the medial/anterior tibial surface superiorly to inferiorly - indicating upper motor neuron defect.
285. Ortner’s syndrome is hoarseness from compression of left recurrent laryngeal nerve by a greatly dilated left atrium (e.g. - in mitral stenosis) - enlarged tracheobronchial lymph nodes - and dilated pulmonary artery.
286. Osler’s nodes is tender to painful - purplish - split pea-sized - subcutaneous nodules in the pulp of the fingers and/or toes and thenar and hypothenar eminences; transient - disappearing within several days (5% of patients); in acute bacterial endocarditis - associated with minute infective emboli; aspiration may reveal the causative organism; in subacute bacterial endocarditis - associated with immune complexes and small-vessel arteritis of skin.
287. Osler-Weber-Rendu disease is hereditary hemorrhagic telangiectasia - larger lesions can be a source of chronic blood loss - systemic emboli - hypoxemia - hepatic dysfunction - and a high-output cardiac failure; important risk factor for brain abscess - especially in affected patients with clubbing - cyanosis - and/or polycythemia; use e--aminocaproic acid (an antifibrinolytic agent).