title: Diurnal Curve of the Ocular Perfusion Pressure.
abstract: OBJECTIVE
  To describe the diurnal variation of the ocular perfusion pressure (OPP) in normal, suspects and glaucoma patients.
  
  
  METHODS
  Seventy-nine subjects were enrolled in a prospective study. The diurnal curve of intraocular pressure (IOP) was performed and blood pressure measurements were obtained. Each participant was grouped into one of the following based upon the clinical evaluation of the optic disk, IOP and standard achromatic perimetry (SAP): 18 eyes were classified as normal (normal SAP, normal optic disk evaluation and IOP < 21 mm Hg in two different measurements), 30 eyes as glaucoma suspect (GS) (normal SAP and mean deviation (MD), C/D ration > 0.5 or asymmetry > 0.2 and/or ocular hypertension), 31 eyes as early glaucoma (MD < -6 dB, glaucomatous optic neuropathy and SAP and MDs on SAP. Standard achromatic perimetry was performed with the Octopus 3.1.1 Dynamic 24-2 program. Intraocular pressure and blood pressure measurements were taken at 6 am, 9 am, 12, 3 and 6 pm. The patients stayed in the seated position for 5 minutes prior to blood pressure measurements.
  
  
  RESULTS
  The mean IOP values in all groups did not follow any regular pattern. The peak IOP was found to be greater in suspect [18.70 ± 3.31 (mm Hg ± SD)] and glaucoma (18.77 ± 4.30 mm Hg) patients as compared to normal subjects (16.11 ± 2.27 mm Hg). In studying the diurnal variation of the OPP, we found lower values at 3 pm in normals (34.21 ± 2.07 mm Hg), at 9 am in suspects (54.35 ± 3.32 mm Hg) and at 12 pm in glaucoma patients (34.84 ± 1.44 mm Hg).
  
  
  CONCLUSIONS
  Each group has a specific OPP variation during the day with the most homogeneous group being the suspect one. It is important to keep studying the IOP and OPP variation for increased comprehension of the pathophysiology of glaucomatous optic neuropathy. How to cite this article: Kanadani FN, Moreira TCA, Bezerra BSP, Vianello MP, Corradi J, Dorairaj SK, Prata TS. Diurnal Curve of the Ocular Perfusion Pressure. J Curr Glaucoma Pract 2016;10(1):4-6.
authors.affiliation: Chief, Department of Glaucoma, Medical Science University Hospital, Belo Horizonte, Brazil.
authors.forename: Fabio N
authors.initials: FN
authors.lastname: Kanadani
authors.affiliation: Assistant Professor, Department of Retina, Medical Science University Hospital, Belo Horizonte, Brazil.
authors.forename: Tca
authors.initials: T
authors.lastname: Moreira
authors.affiliation: Assistant Professor, Department of Glaucoma, Medical Science University Hospital, Belo Horizonte, Brazil.
authors.forename: Bsp
authors.initials: B
authors.lastname: Bezerra
authors.affiliation: Assistant Professor, Department of Glaucoma, Medical Science University Hospital, Belo Horizonte, Brazil.
authors.forename: M P
authors.initials: MP
authors.lastname: Vianello
authors.affiliation: Assistant Professor, Department of Glaucoma, Medical Science University Hospital, Belo Horizonte, Brazil.
authors.forename: J
authors.initials: J
authors.lastname: Corradi
authors.affiliation: Assistant Professor, Department of Ophthalmology/Glaucoma, Mayo Clinic, Jacksonville, Florida, USA.
authors.forename: S K
authors.initials: SK
authors.lastname: Dorairaj
authors.affiliation: Assistant Professor, Department of Glaucoma, Federal University of Sao Paulo Sao Paulo, Brazil.
authors.forename: T S
authors.initials: TS
authors.lastname: Prata
keywords: Diurnal curve; Glaucoma; Ocular perfusion pressure.