title: 24-Hour Intraocular Pressure Rhythm in Patients With Untreated Primary Open Angle Glaucoma and Effects of Selective Laser Trabeculoplasty.
abstract: OBJECTIVE
  The purpose of the study was to evaluate the 24-hour nyctohemeral rhythm of intraocular pressure (IOP) in patients with untreated primary open angle glaucoma using a contact lens sensor. To evaluate the effect of selective laser trabeculoplasty (SLT) on the 24-hour rhythm of IOP.
  
  
  METHODS
  Prospective study conducted in a chronobiology center. Fourteen patients with primary open angle glaucoma underwent three 24-hour IOP measurement sessions after a complete wash-out of the medical treatment: before SLT and 1 and 6 months after, using the contact lens sensor Triggerfish (SENSIMED, Lausanne, Switzerland). IOP and the main parameters of nyctohemeral rhythm (existence of a rhythm, acrophase, bathyphase, midline estimating statistic of rhythm, amplitude, and range) before SLT were compared with the same parameters measured 1 and 6 months later.
  
  
  RESULTS
  IOP increased from 16.3±3.7 to 22.1±8.4 mm Hg (5.8 mm Hg; 95% confidence interval (CI), 2.41-12.71; P=0.009) after the wash-out procedure. After SLT, IOP significantly decreased by 3.4 mm Hg (95% CI, 0.09-7.89; P=0.041) (14.9%) at 1 month and 1.9 mm Hg (95% CI 0.10-3.84; P=0.044) (8.1%) at 6 months. After medication wash-out, 100% of the subjects had a nyctohemeral IOP rhythm with nocturnal acrophase (01:57±3:32 AM, 01:22±3:01 AM, and 03:17±2:12 AM at inclusion, 1 and 6 mo, respectively). SLT did not significantly change the characteristics of the 24-hour IOP pattern, notably the amplitude and the type of rhythm (persistence of nocturnal acrophase).
  
  
  CONCLUSIONS
  After medical treatment wash-out, patients with open angle glaucoma consistently had a significant 24-hour IOP rhythm with nocturnal acrophase. SLT reduces the absolute IOP value but does not modify the nyctohemeral IOP rhythm.
authors.affiliation: *Université Grenoble Alpes †Department of Ophthalmology, University Hospital of Grenoble ‡INSERM U1042, Lab Hypoxia and Physiopathology, Joseph Fourier University, Grenoble, France.
authors.forename: Florent
authors.initials: F
authors.lastname: Aptel
authors.forename: Cécile
authors.initials: C
authors.lastname: Musson
authors.forename: Thierry
authors.initials: T
authors.lastname: Zhou
authors.forename: Antoine
authors.initials: A
authors.lastname: Lesoin
authors.forename: Christophe
authors.initials: C
authors.lastname: Chiquet
mesh_terms: D000368:Aged; D002940:Circadian Rhythm / Q000502:physiology*; D005260:Female; D005902:Glaucoma, Open-Angle / Q000503:physiopathology*; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology*; D053685:Laser Therapy / Q000379:methods*; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014065:Tonometry, Ocular; D014130:Trabeculectomy / Q000379:methods*