Original Article Keep an eye out: A rare case of acute-onset Charles Bonnet Syndrome after Stanford type A aortic dissection repair surgery Fabian Cook 1 , Scott Dougherty 2 , Robert Moreton 1 and Maziar Khorsandi 1 Abstract Charles Bonnet Syndrome describes the triad of complex visual hallucinations secondary to ophthalmic pathology in psychologically normal people. We present a rare case of acute-onset Charles Bonnet Syndrome following cardiac surgery that resulted in profound loss of visual acuity in both eyes with characteristic visual hallucinations that were initially mistaken for delirium. Computed tomography of the brain revealed bilateral occipital infarcts, providing the substrate for Charles Bonnet Syndrome. A high index of suspicion should be maintained in cognitively intact patients with visual loss who are also experiencing visual hallucinations to ensure prompt diagnosis and management of this often overlooked condition. Keywords Aortic dissection, Charles Bonnet Syndrome Introduction Acute Stanford type A aortic dissection is the most common life-threatening disorder that affects the aorta. By definition, it must involve the ascending aorta, although the flap may extend to the aortic arch, the descending aorta and beyond. 1 It is a dramatic medical and surgical emergency with a high mortality rate (1%–2% per hour for the first 24 h). 1,2 Instantaneous onset of severe chest (85%) and/or back pain (46%) are characteristic presenting symp- toms (and may be described as ‘tearing’, ‘heart break- ing’ or ‘crucifying’), but abdominal pain (22%) (due to extension of the dissection flap to the abdominal aorta causing abdominal visceral ischaemia), syncope (13%) and stroke (6%) are also common sequelae. 3 A diastolic murmur from aortic regurgitation is common if the aortic annulus is involved (40%–50% of Stanford type A) and pulsus paradoxus (tamponade), cardio- genic shock (tamponade, aortic regurgitation, coronary ostium occlusion) or hypovolaemic shock (aortic rup- ture) may also be evident. 4 Women with aortic dissec- tion are more likely to present with atypical symptoms which often delays diagnosis and may lead to higher mortality. 4 Annual incidence is 3 per 100,000 in the UK. 5 Risk factors include hypertension, genetic dis- orders (e.g. Marfan’s Syndrome) and previous cardiac surgery (e.g. aortic valve replacement). 6 The precise trigger for aortic dissection remains unknown. Intimal tearing with propagation of blood into the media forcing the intima and adventitia apart, or rupture of the vasa vasorum (the small vessels that supply the aortic wall) which then weakens the aortic wall 3,7 have both been suggested. Initial manage- ment involves close monitoring of pain, cardiac 1 Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, UK 2 Department of Internal Medicine, Belau National Hospital, Republic of Palau Corresponding author: Maziar Khorsandi, Department of Cardiothoracic Surgery, Royal Infirmary of Edinburgh, 51 Little France Crescent, Edinburgh EH16 4SA, UK. Email: maziarkhorsandi@doctors.org.uk Scottish Medical Journal 0(0) 1–4 ! The Author(s) 2017 Reprints and permissions: sagepub.co.uk/journalsPermissions.nav DOI: 10.1177/0036933017696661 journals.sagepub.com/home/scm