title: Evaluation of cystoid change phenotypes in ocular toxoplasmosis using optical coherence tomography.
abstract: OBJECTIVE
  To present unique cystoid changes occurring in patients with ocular toxoplasmosis observed in spectral domain optical coherence tomography (OCT).
  
  
  METHODS
  Forty-six patients (80 eyes) with a diagnosis of ocular toxoplasmosis, who underwent volume OCT examination between January 2005 and October 2012, were retrospectively collected. Review of clinical examination findings, fundus photographs, fluorescein angiograms (FA) and OCT image sets obtained at initial visits and follow-up. Qualitative and quantitative analyses of cystoid space phenotypes visualized using OCT.
  
  
  RESULTS
  Of the 80 eyes included, 17 eyes (15 patients) demonstrated cystoid changes in the macula on OCT. Six eyes (7.5%) had cystoid macular edema (CME), 2 eyes (2.5%) had huge outer retinal cystoid space (HORC), 12 eyes (15%) had cystoid degeneration and additional 3 eyes (3.75%) had outer retinal tubulation due to age related macular degeneration. In one eye with HORC, the lesion was seen in the photoreceptor outer segment, accompanied by photoreceptor elongation and splitting. Three eyes presented with paravascular cystoid degeneration in the inner retina without other macular OCT abnormality.
  
  
  CONCLUSIONS
  In this study, different phenotypes of cystoid spaces seen in eyes with ocular toxoplasmosis using spectral domain OCT (SD-OCT) were demonstrated. CME presented as an uncommon feature, consistently with previous findings. Identification of rare morphological cystoid features (HORC with/without photoreceptor enlongation or splitting) on clinical examination had provided evidence to previous experimental models, which may also expand the clinical spectrum of the disease. Cystoid degeneration in the inner retina next to the retinal vessels in otherwise "normal" looking macula was observed, which may suggest more often clinical evaluation for those patients. Further studies are needed to verify the relevance of cystoid features seen on SD-OCT in assisting with the diagnosis and management of ocular toxoplasmosis.
authors: Charité, University Medicine Berlin, Department of Ophthalmology, Berlin, Germany.
authors: Yanling
authors: Y
authors: Ouyang
authors: Charité, University Medicine Berlin, Department of Ophthalmology, Berlin, Germany.
authors: Uwe
authors: U
authors: Pleyer
authors: Charité, University Medicine Berlin, Department of Ophthalmology, Berlin, Germany.
authors: Qing
authors: Q
authors: Shao
authors: NIHR Biomedical Research Centre for Ophthalmology, Moorfields Eye Hospital NHS Foundation Trust and UCL Institute of Ophthalmology, London, United Kingdom.
authors: Pearse A
authors: PA
authors: Keane
authors: Charité, University Medicine Berlin, Department of Ophthalmology, Berlin, Germany.
authors: Nicole
authors: N
authors: Stübiger
authors: Charité, University Medicine Berlin, Department of Ophthalmology, Berlin, Germany.
authors: Antonia M
authors: AM
authors: Joussen
authors: Doheny Eye Institute and Department of Ophthalmology, Keck School of Medicine of the University of Southern California, Los Angeles, California, United States of America.
authors: Srinivas R
authors: SR
authors: Sadda
authors: Charité, University Medicine Berlin, Department of Ophthalmology, Berlin, Germany.
authors: Florian M
authors: FM
authors: Heussen
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D005260:Female; D006801:Humans; D008266:Macula Lutea / Q000473:pathology* / Q000503:physiopathology; D008268:Macular Degeneration / Q000473:pathology* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D020419:Photoreceptor Cells, Vertebrate / Q000473:pathology*; D012189:Retrospective Studies; D041623:Tomography, Optical Coherence; D014126:Toxoplasmosis, Ocular / Q000473:pathology* / Q000503:physiopathology