title: Low endogenous recanalization in embolic central retinal artery occlusion--the retrobulbar "spot sign".
abstract: OBJECTIVE
  Central retinal artery occlusion (CRAO) is most often indirectly diagnosed by lack of retinal perfusion. Direct embolus characterization may help to understand the natural course and low response to treatment. In a previous study we identified a hyperechoic signal within the optic nerve and in the central retinal artery ("spot sign").
  
  
  METHODS
  In this study we performed a follow-up investigation in 7 patients with CRAO and positive spot sign indicating the embolic cause of the occlusion after a median interval of 17 months (range 11-38 months) using a battery of tests (ocular color-coded sonography, optic coherence tomography [OCT], fundoscopy, amongst others).
  
  
  RESULTS
  The spot sign persisted in all patients, none had high-grade internal carotid artery stenosis, stroke or transient ischemic attacks. Four patients were completely blind, 3 patients were able to recognize hand movements. OCT demonstrated retinal atrophy, and fundoscopy revealed only minimal arterial perfusion.
  
  
  CONCLUSIONS
  The hyperechoic spot sign may be an important predictive prognostic marker for persistent loss of vision. Its persistence may indicate calcified or cholesterol emboli and may explain the low therapeutic success rate to thrombolysis. Further studies on their origin and significance in atherosclerotic disease are warranted.
authors.affiliation: Department of Ophthalmology, University Hospital Regensburg, Franz-Josef-Strauss-Allee 11, 93042, Regensburg, Germany.
authors.forename: Mathias
authors.initials: M
authors.lastname: Altmann
authors.affiliation: Department of Neurology, University of Regensburg, Bezirksklinikum Regensburg, Universitätsstraße 84, 93053, Regensburg, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Ertl
authors.affiliation: Department of Ophthalmology, University Hospital Regensburg, Franz-Josef-Strauss-Allee 11, 93042, Regensburg, Germany.
authors.forename: Horst
authors.initials: H
authors.lastname: Helbig
authors.affiliation: Department of Neurology, University of Regensburg, Bezirksklinikum Regensburg, Universitätsstraße 84, 93053, Regensburg, Germany.
authors.forename: Beate
authors.initials: B
authors.lastname: Schömig
authors.affiliation: Department of Neurology, University of Regensburg, Bezirksklinikum Regensburg, Universitätsstraße 84, 93053, Regensburg, Germany.
authors.forename: Ulrich
authors.initials: U
authors.lastname: Bogdahn
authors.affiliation: Department of Ophthalmology, University Hospital Regensburg, Franz-Josef-Strauss-Allee 11, 93042, Regensburg, Germany.
authors.forename: Maria-Andreea
authors.initials: MA
authors.lastname: Gamulescu
authors.affiliation: Department of Neurology, University of Regensburg, Bezirksklinikum Regensburg, Universitätsstraße 84, 93053, Regensburg, Germany.
authors.forename: Felix
authors.initials: F
authors.lastname: Schlachetzki
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D004617:Embolism / Q000150:complications* / Q000175:diagnosis*; D005260:Female; D006801:Humans; D008297:Male; D015203:Reproducibility of Results; D012161:Retinal Artery / Q000473:pathology; D015356:Retinal Artery Occlusion / Q000175:diagnosis* / Q000209:etiology*; D042262:Retinoscopy / Q000379:methods*; D012680:Sensitivity and Specificity; D041623:Tomography, Optical Coherence / Q000379:methods; D014463:Ultrasonography / Q000379:methods
keywords: Retrobulbar sonography; central retinal artery; etiology; retinal stroke