title: Microcystic macular edema: retrograde maculopathy caused by optic neuropathy.
abstract: OBJECTIVE
  To investigate retrograde axonal degeneration for its potential to cause microcystic macular edema (MME), a maculopathy that has been previously described in patients with demyelinating disease. To identify risk factors for MME and to expand the anatomic knowledge on MME.
  
  
  METHODS
  Retrospective case series.
  
  
  METHODS
  We included 117 consecutive patients and 180 eyes with confirmed optic neuropathy of variable etiology. Patients with glaucoma were excluded.
  
  
  METHODS
  We determined age, sex, visual acuity, etiology of optic neuropathy, and the temporal and spatial characteristics of MME. Eyes with MME were compared with eyes with optic neuropathy alone and to healthy fellow eyes. With retinal layer segmentation we quantitatively measured the intraretinal anatomy.
  
  
  METHODS
  Demographic data, distribution of MME in the retina, and thickness of retinal layers were analyzed.
  
  
  RESULTS
  We found MME in 16 eyes (8.8%) from 9 patients, none of whom had multiple sclerosis or neuromyelitis optica. The MME was restricted to the inner nuclear layer (INL) and had a characteristic perifoveal circular distribution. Compared with healthy controls, MME was associated with significant thinning of the ganglion cell layer and nerve fiber layer, as well as a thickening of the INL and the deeper retinal layers. Youth is a significant risk factor for MME.
  
  
  CONCLUSIONS
  Microcystic macular edema is not specific for demyelinating disease. It is a sign of optic neuropathy irrespective of its etiology. The distinctive intraretinal anatomy suggests that MME is caused by retrograde degeneration of the inner retinal layers, resulting in impaired fluid resorption in the macula.
authors.affiliation: Department of Ophthalmology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland. Electronic address: mathias.abegg@insel.ch.
authors.forename: Mathias
authors.initials: M
authors.lastname: Abegg
authors.affiliation: Department of Ophthalmology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland.
authors.forename: Muriel
authors.initials: M
authors.lastname: Dysli
authors.affiliation: Department of Ophthalmology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Wolf
authors.affiliation: ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland.
authors.forename: Jens
authors.initials: J
authors.lastname: Kowal
authors.affiliation: ARTORG Center for Biomedical Engineering Research, University of Bern, Bern, Switzerland.
authors.forename: Pascal
authors.initials: P
authors.lastname: Dufour
authors.affiliation: Department of Ophthalmology, Inselspital, Bern University Hospital, and University of Bern, Bern, Switzerland.
authors.forename: Martin
authors.initials: M
authors.lastname: Zinkernagel
mesh_terms: D001369:Axons / Q000473:pathology*; D005260:Female; D006801:Humans; D008269:Macular Edema / Q000175:diagnosis / Q000209:etiology*; D008279:Magnetic Resonance Imaging; D008297:Male; D009410:Nerve Degeneration / Q000473:pathology; D009901:Optic Nerve Diseases / Q000150:complications*; D012165:Retinal Ganglion Cells / Q000473:pathology; D012189:Retrospective Studies; D012307:Risk Factors; D013997:Time Factors; D041623:Tomography, Optical Coherence; D014792:Visual Acuity / Q000502:physiology