title: Macular Microcysts in Mitochondrial Optic Neuropathies: Prevalence and Retinal Layer Thickness Measurements.
abstract: OBJECTIVE
  To investigate the thickness of the retinal layers and to assess the prevalence of macular microcysts (MM) in the inner nuclear layer (INL) of patients with mitochondrial optic neuropathies (MON).
  
  
  METHODS
  All patients with molecularly confirmed MON, i.e. Leber's Hereditary Optic Neuropathy (LHON) and Dominant Optic Atrophy (DOA), referred between 2010 and 2012 were enrolled. Eight patients with MM were compared with two control groups: MON patients without MM matched by age, peripapillary retinal nerve fiber layer (RNFL) thickness, and visual acuity, as well as age-matched controls. Retinal segmentation was performed using specific Optical coherence tomography (OCT) software (Carl Zeiss Meditec). Macular segmentation thickness values of the three groups were compared by one-way analysis of variance with Bonferroni post hoc corrections.
  
  
  RESULTS
  MM were identified in 5/90 (5.6%) patients with LHON and 3/58 (5.2%) with DOA. The INL was thicker in patients with MON compared to controls regardless of the presence of MM [133.1±7μm vs 122.3±9μm in MM patients (p<0.01) and 128.5±8μm vs. 122.3±9μm in no-MM patients (p<0.05)], however the outer nuclear layer (ONL) was thicker in patients with MM (101.4±1mμ) compared to patients without MM [77.5±8mμ (p<0.001)] and controls [78.4±7mμ (p<0.001)]. ONL thickness did not significantly differ between patients without MM and controls.
  
  
  CONCLUSIONS
  The prevalence of MM in MON is low (5-6%), but associated with ONL thickening. We speculate that in MON patients with MM, vitreo-retinal traction contributes to the thickening of ONL as well as to the production of cystic spaces.
authors.affiliation: IRCCS, Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, Bologna, Italy.
authors.forename: Michele
authors.initials: M
authors.lastname: Carbonelli
authors.affiliation: IRCCS, Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, Bologna, Italy; Neurology Unit, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: La Morgia
authors.affiliation: G.B. Bietti Foundation, IRCCS, Rome, Italy.
authors.forename: Giacomo
authors.initials: G
authors.lastname: Savini
authors.affiliation: San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Maria Lucia
authors.initials: ML
authors.lastname: Cascavilla
authors.affiliation: San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Enrico
authors.initials: E
authors.lastname: Borrelli
authors.affiliation: Department of Ophthalmology, Federal University of São Paulo, UNIFESP, São Paulo, Brazil.
authors.forename: Filipe
authors.initials: F
authors.lastname: Chicani
authors.affiliation: Department of Ophthalmology, Federal University of São Paulo, UNIFESP, São Paulo, Brazil.
authors.forename: Carolina
authors.initials: C
authors.lastname: do V F Ramos
authors.affiliation: Department of Ophthalmology, Federal University of São Paulo, UNIFESP, São Paulo, Brazil.
authors.forename: Solange R
authors.initials: SR
authors.lastname: Salomao
authors.affiliation: G.B. Bietti Foundation, IRCCS, Rome, Italy.
authors.forename: Vincenzo
authors.initials: V
authors.lastname: Parisi
authors.affiliation: Doheny Eye Institute, Los Angeles, University of California Los Angeles, Los Angeles, California, United States of America; VMR Institute for Vitreous Macula Retina, Huntington Beach, California, United States of America.
authors.forename: Jerry
authors.initials: J
authors.lastname: Sebag
authors.affiliation: San Raffaele Scientific Institute, Milan, Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Bandello
authors.affiliation: Doheny Eye Institute, Los Angeles, University of California Los Angeles, Los Angeles, California, United States of America.
authors.forename: Alfredo A
authors.initials: AA
authors.lastname: Sadun
authors.affiliation: IRCCS, Istituto delle Scienze Neurologiche di Bologna, Bellaria Hospital, Bologna, Italy; Neurology Unit, Department of Biomedical and Neuromotor Sciences (DIBINEM), University of Bologna, Bologna, Italy.
authors.forename: Valerio
authors.initials: V
authors.lastname: Carelli
authors.affiliation: San Raffaele Scientific Institute, Milan, Italy; Studio Oculistico d'Azeglio, Bologna, Italy.
authors.forename: Piero
authors.initials: P
authors.lastname: Barboni
mesh_terms: D000328:Adult; D000465:Algorithms; D016022:Case-Control Studies; D003710:Demography; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009412:Nerve Fibers / Q000502:physiology; D029241:Optic Atrophy, Autosomal Dominant / Q000453:epidemiology / Q000473:pathology; D029242:Optic Atrophy, Hereditary, Leber / Q000453:epidemiology / Q000473:pathology*; D009900:Optic Nerve / Q000502:physiology; D015995:Prevalence; D011859:Radiography; D012160:Retina / Q000000981:diagnostic imaging / Q000503:physiopathology*; D041623:Tomography, Optical Coherence; D014792:Visual Acuity