Postural studies in pulsatile ocular blood flow: II. Chronic open angle glaucoma.

The intra-ocular pressure rises when body position is changed from sitting to supine. This phenomenon occurs to the same extent in healthy people and glaucoma patients. The purpose of this preliminary study was to determine the effect of posture on the visual field. Visual fields of 15 eyes of 12 normal-tension glaucoma (NTG) patients, 16 eyes of 11 high-tension glaucoma (HTG) patients and 30 eyes of 26 healthy controls were measured in the upright and supine positions with program GIX on an Octopus swivel-arm perimeter. The delta mean defect (ΔMD), that is MDupright–MDsupine, was calculated for each patient and compared among study groups. Whereas visual fields improved in healthy controls (ΔMD = +0.45 dB), glaucoma patients showed a slight deterioration of the visual field after changing position from supine to upright (HTG: ΔMD = ––0.25 dB, NTG: ΔMD = ––0.24 dB). The difference between HTG and controls, as well as between NTG and controls, was statistically significant (p < 0.002, Student’s t test). These findings indicate that in some glaucoma patients the regulatory mechanisms for blood supply in the optic nerve head are insufficient.

Section: Introductionmentioning

confidence: 91%

Influence of Posture on the Visual Field in Glaucoma Patients and Controls

Lietz

Kaiser²,

Stümpfig³

1995

“…Trew und Smith [24] stellten keine Steigerung des pulsatilen okulären Blutflusses nach Gabe von Timolol 0,25% bei HDG-Patienten fest, während Boles Carenini et al [25] nach Gabe von Timolol 0,5% eine signifikante Reduktion des pulsatilen okulären Blutflusses feststellten; Martin und Rabineau [26] fanden eine Reduktion des mittleren Durchmessers der Netzhautarterien. Nach Gabe von Pilokarpin 2 und 4% fanden Boles Carenini et al [27] eine Steigerung des pulsatilen okulären Blutflusses.…”

Section: Diskussionunclassified

Okuläre Pulsamplitude bei okulärer Hypertension und verschiedenen Glaukomformen

Rückmann²,

Mittag³

1997

The present study was designed to investigate choroidal perfusion in primary open-angle glaucoma patients with statistically elevated (HPG) and statistically normal (NPG) intraocular pressure (IOP) and in ocular hypertensive volunteers (OHT) before and after application of topical antiglaucomatous drugs. When compared to age-matched healthy controls, ocular pulse amplitude (OPA) and IOP were significantly increased in OHT and unchanged in HPG; in NPG, the IOP was unchanged, and the OPA was significantly reduced. The topical antiglaucomatous drugs used in this study reduced IOP, but did not increase OPA. When compared to HPG and NPG, OHT subjects showed increased choroidal perfusion which may help to prevent glaucomatous optic nerve damage.

“…The ‘OBF system’ calculates the pulsatile component of the OBF from the pulsatile intraocular pressure (IOP) changes; a significant pulsatile OBF reduction has been reported in primary open-angle glaucoma (POAG) and in normal-tension glaucoma (NTG) [14, 15]. Besides that, in glaucomatous patients prolonged dye transit times have been found on fluorescein videoangiography [16, 17]while laser Doppler velocimetry (measuring blood cell velocity in retinal vessels) showed decreased optic nerve head blood flow velocity in glaucoma [9].…”

Section: Introductionmentioning

confidence: 99%

Effects of Timolol and Dorzolamide on Retrobulbar Hemodynamics in Patients with Newly Diagnosed Primary Open-Angle Glaucoma

Galassi¹,

Sodi²,

Renieri³

et al. 2002

The authors considered a group of patients with newly diagnosed primary open-angle glaucoma studying the effects of a 4-week treatment with timolol or dorzolamide on retrobulbar vessels. Ocular hemodynamics were assessed by means of color Doppler imaging of the ophthalmic artery, the temporal short posterior ciliary arteries (SPCAs) and the central retinal artery. For each vessel, systolic and diastolic blood flow velocities were measured, and the resistivity index (RI) was calculated. The only significant result was a reduction of temporal SPCA RI after dorzolamide treatment in comparison with baseline (p = 0.011). In the same group, dorzolamide treatment had a slight and nonsignificant increase in temporal SPCA diastolic velocity. The resistance decrease observed after dorzolamide treatment in the ciliary circulation may be due to the decrease in intraocular pressure or a possible direct vasodilating effect of the drug.