title: Outer retinal microstructure in a case of acute idiopathic blind spot enlargement syndrome.
abstract: OBJECTIVE
  To present a patient with acute idiopathic blind spot enlargement syndrome who had abnormal changes in the outer retinal microstructure limited to areas with reduced responses on multifocal electroretinograms as well as to the area involving a scotoma.
  
  
  RESULTS
  We report the case of a 44-year-old man who developed an arcuate scotoma which was associated with a physiological blind spot in the left eye. The ophthalmoscopic, fluorescein angiographic, and full-field electroretinogram findings were normal. The amplitudes of the multifocal electroretinograms were reduced in the area of the scotoma. Optical coherence tomography showed that both the external limiting membrane and the inner and outer segment (IS/OS) line were intact, but that the middle cone outer segment tip line between the IS/OS line and the retinal pigment epithelium was absent in the nasal macular area of the left eye.
  
  
  CONCLUSIONS
  These findings indicate that the integrity of not only the external limiting membrane and IS/OS line but also the cone outer segment tip line is important for the function of the retina.
authors.affiliation: Department of Ophthalmology, Inoue Ganka Clinic, University Hospital Itabashi, Tokyo, Japan.
authors.forename: Michitaka
authors.initials: M
authors.lastname: Sugahara
authors.forename: Kei
authors.initials: K
authors.lastname: Shinoda
authors.forename: Soiti Celso
authors.initials: SC
authors.lastname: Matsumoto
authors.forename: Shingo
authors.initials: S
authors.lastname: Satofuka
authors.forename: Gen
authors.initials: G
authors.lastname: Hanazono
authors.forename: Yutaka
authors.initials: Y
authors.lastname: Imamura
authors.forename: Atsushi
authors.initials: A
authors.lastname: Mizota