title: B-mode transorbital ultrasononography for the diagnosis of acute optic neuritis. A systematic review.
abstract: OBJECTIVE
  In patients with acute optic neuritis (AON) transorbital sonography may reveal a thickening of the retrobulbar portion of the optic nerve. Our aim was to systematically review the diagnostic accuracy of ultrasonography of optic nerve diameter (OND) for assessment of AON.
  
  
  METHODS
  MEDLINE, EMBASE (1966-October 2014) was searched to identify studies reporting data on patients with AON (with/without multiple sclerosis) assessed by B-mode transorbital ultrasonography. Thereafter, the studies retrieved were screened based on predefined inclusion and exclusion criteria. Data were extracted and the quality of the included studies was evaluated.
  
  
  RESULTS
  Seven studies (162 patients) were included. The OND was significantly thicker in the affected eye compared with its unaffected fellow or controls. An increased OND was found in 78-100% of patients. Four studies determined papilledema in 6-43% of patients.
  
  
  CONCLUSIONS
  Transorbital sonography is a sensitive, highly accessible and user-friendly technique for the detection of significant optic nerve thickening on the side affected by AON and represents an adjunctive tool for the diagnosis of AON. Compared to visual evoked potentials, TOS may provide different, though complementary, information on the pathophysiology of AON.
  
  
  CONCLUSIONS
  B-mode transorbital ultrasonography provides promising support for the clinical diagnosis of AON.
authors.affiliation: Department of Neurology, Franz Tappeiner Hospital, Merano, Italy; Department of Neurology, University A. Avogadro, Novara, Italy.
authors.forename: Piergiorgio
authors.initials: P
authors.lastname: Lochner
authors.affiliation: Neurology Unit, IRCCS Casa Sollievo Della Sofferenza, San Giovanni Rotondo, Italy; IRCAD, Interdisciplinary Research Center of Autoimmune Diseases, Novara, Italy.
authors.forename: Maurizio A
authors.initials: MA
authors.lastname: Leone
authors.affiliation: Department of Neurology, University A. Avogadro, Novara, Italy.
authors.forename: Lorenzo
authors.initials: L
authors.lastname: Coppo
authors.affiliation: Department of Neurology, Christian Doppler Clinic, Paracelsus Medical University, Salzburg, Austria.
authors.forename: Raffaele
authors.initials: R
authors.lastname: Nardone
authors.affiliation: Neurology Unit, Stroke Unit, IRCCS, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy.
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Zedde
authors.affiliation: Department of Neurology, University A. Avogadro, Novara, Italy.
authors.forename: Roberto
authors.initials: R
authors.lastname: Cantello
authors.affiliation: Department of Neurology, University A. Avogadro, Novara, Italy; Department of Neurological, Neuropsychological, Morphological and Movement Sciences, Section of Clinical Neurology, University of Verona, Italy. Electronic address: dr.francescobrigo@gmail.com.
authors.forename: Francesco
authors.initials: F
authors.lastname: Brigo
mesh_terms: D000208:Acute Disease; D006801:Humans; D009900:Optic Nerve / Q000000981:diagnostic imaging*; D009902:Optic Neuritis / Q000000981:diagnostic imaging*; D009915:Orbit / Q000000981:diagnostic imaging*; D018616:Ultrasonography, Doppler, Duplex / Q000379:methods
keywords: Acute optic neuritis; Optic nerve diameter; Optic nerve sheath; Transorbital sonography