title: Macular retinal ganglion cell-inner plexiform layer thickness in patients on hydroxychloroquine therapy.
abstract: OBJECTIVE
  We evaluated macular ganglion cell-inner plexiform layer (GC-IPL) thickness using spectral-domain optical coherence tomography (SD-OCT) in patients with chronic exposure to hydroxychloroquine (HCQ).
  
  
  METHODS
  This study included 130 subjects, who were divided into three groups: Group 1A, 55 patients with HCQ use ≥5 years; Group 1B, 46 patients with HCQ use <5 years; and Group 2, 29 normal controls. In all patients with exposure to HCQ, fundus examination, automated threshold perimetry, fundus autofluorescence photography, SD-OCT, and GC-IPL thickness measurement using the Cirrus HD-OCT ganglion cell analysis algorithm were performed. Average and minimum macular GC-IPL thickness were compared between subjects groups, and correlations between GC-IPL thickness and duration or total dose of HCQ use were analyzed.
  
  
  RESULTS
  Among the 101 patients of Group 1, six patients who showed clinically evident HCQ retinopathy also showed markedly thin macular GC-IPL. In addition, weak but significant negative correlations were observed between the average and minimum GC-IPL thickness of Group 1 patients and cumulative dose of HCQ, even when analyzing without the six patients with HCQ retinopathy. However, when analyzing after exclusion of patients with high cumulative doses (>1000 g), significant correlations were not observed.
  
  
  CONCLUSIONS
  This study revealed that macular GC-IPL thickness did not show definite correlations with HCQ use. However, some patients, especially with HCQ retinopathy or high cumulative doses, showed thin GC-IPL.
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Min Gyu
authors.initials: MG
authors.lastname: Lee
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Sang Jin
authors.initials: SJ
authors.lastname: Kim
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Don-Il
authors.initials: DI
authors.lastname: Ham
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Se Woong
authors.initials: SW
authors.lastname: Kang
authors.affiliation: Department of Ophthalmology, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Changwon
authors.initials: C
authors.lastname: Kee
authors.affiliation: Division of Rheumatology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Jaejoon
authors.initials: J
authors.lastname: Lee
authors.affiliation: Division of Rheumatology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Hoon-Suk
authors.initials: HS
authors.lastname: Cha
authors.affiliation: Division of Rheumatology, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea.
authors.forename: Eun-Mi
authors.initials: EM
authors.lastname: Koh
mesh_terms: D000328:Adult; D018501:Antirheumatic Agents / Q000009:adverse effects / Q000627:therapeutic use; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D006886:Hydroxychloroquine / Q000009:adverse effects* / Q000627:therapeutic use; D008297:Male; D009412:Nerve Fibers / Q000187:drug effects / Q000473:pathology*; D012164:Retinal Diseases / Q000139:chemically induced / Q000175:diagnosis*; D012165:Retinal Ganglion Cells / Q000187:drug effects / Q000473:pathology*; D012189:Retrospective Studies; D012216:Rheumatic Diseases / Q000188:drug therapy; D041623:Tomography, Optical Coherence / Q000379:methods*
chemical_list: D018501:Antirheumatic Agents; D006886:Hydroxychloroquine
keywords: hydroxychloroquine; hydroxychloroquine retinopathy; retinal ganglion cell