title: Binarization of enhanced depth imaging optical coherence tomographic images of an eye with Wyburn-Mason syndrome: a case report.
abstract: BACKGROUND
  To report a thicker choroid and larger choroidal luminal area in an eye with Wyburn-Mason syndrome. To the best of our knowledge, this is the first report demonstrating an increase in the choroidal thickness and the luminal area in a case of Wyburn-Mason syndrome. In addition, we report the changing appearance of retinal arteriovenous malformations over a 16-year period.
  
  
  METHODS
  A 27-year-old woman, who was diagnosed with Wyburn-Mason syndrome at age 11 years, visited our clinic. Her best-corrected visual acuity was 20/12.5 in the right eye and light perception in the left eye. Severely dilated, tortuous vascular loops were distributed from the optic disc over all four quadrants of the left fundus. The vascular loops in some areas were more dilated and tortuous than 16 years earlier. Optical coherence tomography (OCT) showed retinal edema with cystic changes and enlarged choroidal vessel lumens in the left eye. The subfoveal choroidal thickness was manually measured by the caliper function in the enhanced depth imaging OCT (EDI-OCT) images. Binarization of the EDI-OCT images was performed with publicly accessible ImageJ software. The examined area of the subfoveal choroid was 1,500 μm wide, and the dark areas representing the luminal areas were traced by the Niblack method. After determining the distance of each pixel, the luminal area was automatically calculated. The subfoveal choroidal thickness was 250 μm in the right eye and 462 μm in the left eye. The luminal area of the 1,500-μm-wide subfoveal choroid was computed to be 307,165.6 μm(2) in the right eye and 545,780.7 μm(2) in the left eye.
  
  
  CONCLUSIONS
  The EDI-OCT images showed a thicker choroid, and binarization of the EDI-OCT images showed that the luminal areas were significantly larger in the affected eye, suggesting a dilatation of the choroidal vessels. The results demonstrated that conversion of EDI-OCT images to binary images was a useful method to quantify the choroidal structure.
authors.affiliation: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15, Kuramoto-cho, Tokushima, 770-8503, Japan. rtpgg803@yahoo.co.jp.
authors.forename: Akiko
authors.initials: A
authors.lastname: Iwata
authors.affiliation: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15, Kuramoto-cho, Tokushima, 770-8503, Japan. ymitaymitaymita@yahoo.co.jp.
authors.forename: Yoshinori
authors.initials: Y
authors.lastname: Mitamura
authors.affiliation: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15, Kuramoto-cho, Tokushima, 770-8503, Japan. niki_6cameo@yahoo.co.jp.
authors.forename: Masanori
authors.initials: M
authors.lastname: Niki
authors.affiliation: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15, Kuramoto-cho, Tokushima, 770-8503, Japan. banho0317@yahoo.co.jp.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Semba
authors.affiliation: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15, Kuramoto-cho, Tokushima, 770-8503, Japan. egawa.m@tokushima-u.ac.jp.
authors.forename: Mariko
authors.initials: M
authors.lastname: Egawa
authors.affiliation: Department of Ophthalmology, Institute of Health Biosciences, The University of Tokushima Graduate School, 3-18-15, Kuramoto-cho, Tokushima, 770-8503, Japan. katome@tokushima-u.ac.jp.
authors.forename: Takashi
authors.initials: T
authors.lastname: Katome
authors.affiliation: Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima, 890-8520, Japan. shou@m3.kufm.kagoshima-u.ac.jp.
authors.forename: Shozo
authors.initials: S
authors.lastname: Sonoda
authors.affiliation: Department of Ophthalmology, Kagoshima University Graduate School of Medical and Dental Sciences, 8-35-1 Sakuragaoka, Kagoshima, 890-8520, Japan. tsakamot@m3.kufm.kagoshima-u.ac.jp.
authors.forename: Taiji
authors.initials: T
authors.lastname: Sakamoto
mesh_terms: D000328:Adult; D001164:Arteriovenous Fistula / Q000175:diagnosis*; D001165:Arteriovenous Malformations / Q000175:diagnosis*; D002829:Choroid / Q000473:pathology*; D015862:Choroid Diseases / Q000175:diagnosis*; D005260:Female; D005451:Fluorescein Angiography; D006801:Humans; D020752:Neurocutaneous Syndromes / Q000175:diagnosis*; D009929:Organ Size; D012161:Retinal Artery / Q000002:abnormalities*; D012169:Retinal Vein / Q000002:abnormalities*; D041623:Tomography, Optical Coherence; D014792:Visual Acuity