title: Ocular rigidity and outflow facility in nonproliferative diabetic retinopathy.
abstract: OBJECTIVE
  To compare ocular rigidity (OR) and outflow facility (C) in patients with nonproliferative diabetic retinopathy (NPDR) and control subjects.
  
  
  METHODS
  Twenty-four patients with NPDR (NPDR group) and 24 controls (control group) undergoing cataract surgery were enrolled. NPDR group was further divided into patients with mild NPDR (NPDR1-group) and patients with moderate and/or severe NPDR (NPDR2-group). After cannulation of the anterior chamber, a computer-controlled device was used to infuse saline and increase the intraocular pressure (IOP) in a stepping procedure from 15 to 40 mmHg. Ocular rigidity and outflow facility coefficients were estimated from IOP and volume recordings.
  
  
  RESULTS
  Ocular rigidity was 0.0205 μL(-1) in NPDR group and 0.0202 μL(-1) in control group (P = 0.942). In NPDR1-group, OR was 0.017 μL(-1) and in NPDR2-group it was 0.025 μL(-1) (P = 0.192). Outflow facility was 0.120 μL/min/mmHg in NPDR-group compared to 0.153 μL/min/mmHg in the control group at an IOP of 35 mmHg (P = 0.151). There was no difference in C between NPDR1-group and NPDR2-group (P = 0.709).
  
  
  CONCLUSIONS
  No statistically significant differences in ocular rigidity and outflow facility could be documented between diabetic patients and controls. No difference in OR and C was detected between mild NPDR and severe NPDR.
authors.affiliation: Department of Ophthalmology, University Hospital of Heraklion, 71110 Heraklion, Greece ; Department of Ophthalmology, Venizeleio General Hospital of Heraklion, 71409 Heraklion, Greece.
authors.forename: Theonitsa
authors.identifier: 0000-0003-3553-1779
authors.initials: T
authors.lastname: Panagiotoglou
authors.affiliation: Department of Ophthalmology, University Hospital of Heraklion, 71110 Heraklion, Greece ; Institute of Vision and Optics, School of Medicine, University of Crete, 71110 Heraklion, Greece.
authors.forename: Miltiadis
authors.identifier: 0000-0002-0130-1150
authors.initials: M
authors.lastname: Tsilimbaris
authors.affiliation: Institute of Vision and Optics, School of Medicine, University of Crete, 71110 Heraklion, Greece.
authors.forename: Harilaos
authors.initials: H
authors.lastname: Ginis
authors.affiliation: Institute of Vision and Optics, School of Medicine, University of Crete, 71110 Heraklion, Greece.
authors.forename: Nikos
authors.initials: N
authors.lastname: Karyotakis
authors.affiliation: Department of Social Medicine, School of Medicine, University of Crete, 71110 Heraklion, Greece.
authors.forename: Vaggelis
authors.initials: V
authors.lastname: Georgiou
authors.affiliation: Department of Ophthalmology, Venizeleio General Hospital of Heraklion, 71409 Heraklion, Greece.
authors.forename: Pavlos
authors.initials: P
authors.lastname: Koutentakis
authors.affiliation: Department of Ophthalmology, University Hospital of Heraklion, 71110 Heraklion, Greece ; Institute of Vision and Optics, School of Medicine, University of Crete, 71110 Heraklion, Greece.
authors.forename: Ioannis
authors.initials: I
authors.lastname: Pallikaris
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D002386:Cataract / Q000150:complications / Q000503:physiopathology; D002387:Cataract Extraction; D003930:Diabetic Retinopathy / Q000150:complications / Q000503:physiopathology*; D005123:Eye / Q000503:physiopathology*; D005260:Female; D006801:Humans; D007429:Intraocular Pressure / Q000502:physiology; D008297:Male; D008875:Middle Aged