title: Extent of asymmetry and unilaterality among juvenile onset primary open angle glaucoma patients.
abstract: BACKGROUND
  Juvenile onset open angle glaucoma (JOAG) due to its rarity is not well characterized. We aimed to assess the extent of interocular asymmetry of baseline intraocular pressure (IOP), disc morphometry and visual field defects at presentation in patients with primary JOAG.
  
  
  METHODS
  Retrospective, single-centre, hospital-based study.
  
  
  METHODS
  Fifty-two consecutive JOAG patients who presented with glaucomatous optic neuropathy in at least one eye, without any secondary causes of glaucoma.
  
  
  METHODS
  Participants were evaluated for baseline clinical features. The optic disc parameters were measured using scanning laser ophthalmoscopy (Heidelberg Retina Tomograph). Reliable and reproducible visual field tests using standard 30-2 Humphrey automated perimetry were analysed.
  
  
  METHODS
  Interocular asymmetry of baseline IOP, vertical cup:disc ratio and mean deviation.
  
  
  RESULTS
  Fourteen patients (27%) had glaucomatous optic neuropathy in only one eye at initial presentation; the fellow eyes of which had IOP <21 mmHg in eight whereas six had IOP >21 mmHg. In 20 out of 52 patients (39%) one eye remained perimetrically unaffected. Patients presenting with bilateral optic neuropathy were found to be significantly younger (24.4 ± 10.6 years) in age compared to those with unilateral optic neuropathy (32 ± 8.2 years) (P = 0.02).
  
  
  CONCLUSIONS
  One-fourth of primary JOAG patients present as a unilateral optic neuropathy with 60% of these having normal IOP in the fellow eyes. Primary JOAG may present with considerable asymmetry with a small proportion presenting as a unilateral disease.
authors.affiliation: Dr. Rajendra Prasad Centre for Ophthalmic Sciences             Department of Biostatistics, All India Institute of Medical Sciences, New Delhi, India.
authors.forename: Viney
authors.initials: V
authors.lastname: Gupta
authors.forename: Shikha
authors.initials: S
authors.lastname: Gupta
authors.forename: Munish
authors.initials: M
authors.lastname: Dhawan
authors.forename: Ajay
authors.initials: A
authors.lastname: Sharma
authors.forename: Kulwant S
authors.initials: KS
authors.lastname: Kapoor
authors.forename: Ramanjit
authors.initials: R
authors.lastname: Sihota
mesh_terms: D000293:Adolescent; D000328:Adult; D002648:Child; D005260:Female; D005902:Glaucoma, Open-Angle / Q000175:diagnosis* / Q000503:physiopathology; D006801:Humans; D007429:Intraocular Pressure; D008297:Male; D009887:Ophthalmoscopy; D009898:Optic Disk / Q000473:pathology*; D009901:Optic Nerve Diseases / Q000175:diagnosis* / Q000503:physiopathology; D012189:Retrospective Studies; D014786:Vision Disorders / Q000175:diagnosis* / Q000503:physiopathology; D058609:Visual Field Tests; D014794:Visual Fields; D055815:Young Adult