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1.
AIM: To determine the ocular haemodynamic response to gas perturbations in glaucoma. METHODS: Intraocular pressure (IOP), systemic systolic and diastolic blood pressure (SBP and DBP), and retrobulbar blood flow velocities, measured by colour Doppler imaging (CDI), were recorded at two visits. CDI was used to measure peak systolic and end diastolic velocities (PSV and EDV) and resistance index (RI) in the ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (SPCAs). At the first visit, measurements were taken at baseline (B1: breathing room air) and during isoxic hypercapnia (end tidal PCO(2) increased 15% above baseline) in 16 normal subjects and 12 patients with glaucoma. On another day, measurements were repeated at a second baseline (B2) and during hyperoxia (100% oxygen breathing) for 15 normal subjects and 13 glaucoma patients. Baseline systemic data were compared using paired t tests; REANOVA was performed to compare group differences at baseline and to determine the vessel response to each condition. Fisher's LSD was used for post hoc comparison. RESULTS: Baseline OA PSV was lower for the glaucoma than for the normal group (p = 0.047); the groups were otherwise similar at baseline. IOP demonstrated no response to hypercapnia, but reduced during hyperoxia for both the normal subjects (p<0.0001) and glaucoma patients (p = 0.04). During hypercapnia, SBP increased in normal subjects (p = 0.03) and glaucoma patients (p = 0.01); DBP increased in normal subjects (p = 0.021). There was a corresponding increase in ocular perfusion pressure (OPP) for normal subjects (p = 0.01) and glaucoma subjects (p = 0.028), and as a result OPP was included as a covariate in the REANCOVA model. Hypercapnia resulted in increased PSV in the CRA of normal subjects (p = 0.035) and increased PSV and EDV in the SPCAs of glaucoma patients (p = 0.041 and p = 0.030 respectively). Hyperoxia resulted in reduced PSV and EDV in the ophthalmic arteries of normal subjects only (p = 0.001 and 0.031 respectively). CONCLUSIONS: These findings suggest the presence of relative vasoconstriction in glaucoma patients, which is at least partially reversed by hypercapnia.  相似文献   

2.
Aim The purpose of this study was to investigate the effects of glaucoma surgery on retrobulbar hemodynamics and corneal surface temperature (CST). Methods A total of 22 primary open-angle glaucoma eyes underwent deep sclerectomy, and 19 trabeculectomy. The follow-up was of 3 months. The peak systolic velocity (PSV), end-diastolic velocity (EDV), and resistivity index (RI) were evaluated in the ophthalmic artery (OA), central retinal artery (CRA), and short posterior ciliary arteries (SPCAs) by color Doppler imaging (CDI). CST was measured using infrared thermography. Results At 3 months, EDV was increased in OA (P < 0.001 in deep sclerectomy, P = 0.005 in trabeculectomy), CRA (P = 0.044 and P < 0.001), and SPCAs (P = 0.011 and P = 0.003), and RI decreased in OA, CRA, and SPCAs (P < 0.001 in both groups). CST values were augmented (P < 0.001 in both groups). A negative correlation between the postoperative changes in RI-OA and CST was found (P = 0.023 and P = 0.032, respectively). Conclusions Deep sclerectomy and trabeculectomy seem to be equally effective in improving retrobulbar hemodynamics. Color Doppler imaging and infrared thermography might be useful to evaluate the vascular outcome of glaucoma surgery.  相似文献   

3.
BACKGROUND: Ocular surface temperature (OST) could berelated to retrobulbar haemodynamics in patients with glaucoma. AIMS: To compare OST measurements in patients with glaucoma and healthy controls, and to investigate the correlation between OST, intraocular pressure (IOP) and retrobulbar haemodynamics in patients with glaucoma. METHODS: 32 patients with primary open-angle glaucoma (POAG) and 40 controls were included in the study. The parameters considered both in patients with POAG and in controls were IOP and OST values measured by infrared ocular thermography. Colour Doppler imaging was used to determine haemodynamic parameters in ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (SPCAs) in patients with POAG. RESULTS: OST values were significantly lower in patients with POAG than in controls (p<0.001). OST was negatively related with resistivity index of OA (p<0.001), CRA (p = 0.001) and SPCAs (p<0.001), and positively related with end-diastolic velocity of OA (p = 0.02) and SPCAs (p = 0.05). CONCLUSION: This study suggested that OST could be a marker of impaired retrobulbar haemodynamics in patients with glaucoma.  相似文献   

4.
OBJECTIVE: To compare the hemodynamic parameters in the retrobulbar vessels in pseudoexfoliative syndrome (PXS), pseudoexfoliative glaucoma (PXG), and age-matched healthy subjects by using color Doppler imaging (CDI). SUBJECTS AND METHODS: 72 eyes from 72 patients with PXS, 70 eyes from 70 patients with PXG, and 66 eyes from 66 age-matched healthy subjects who met the inclusion/exclusion criteria were included in this prospective cross-sectional study. Peak systolic velocity (PSV), end-diastolic velocity (EDV), and Pourcelot resistance index (RI) were assessed in the ophthalmic artery (OA), central retinal artery (CRA), and temporal short-posterior ciliary arteries (SPCA). Visual function was assessed using the 24-2 Swedish Interactive Threshold Algorithm (SITA). The main outcomes of the study were PSV, EDV and RI in the OA, SPCA, and CRA. RESULTS: The EDV in the OA, SPCA and the CRA was decreased significantly (p < 0.001, <0.001, and 0.003 respectively) in the eyes of PXG patients compared with controls and PSX respectively. The RI in the OA, SPCA, and the CRA was significantly higher (p = 0.022, 0.005, and 0.007 respectively) in the eyes of PXG patients compared with healthy controls and PSX patients respectively. The mean difference in mean EDV in the OA between the control group and the PXS was 0.18 cm/s, 95% confidence interval (CI) -0.60 to 0.95, p = 0.661. The mean difference in mean EDV in the SPCA between the control healthy subjects and the pseudoexfoliative subjects was -0.18 cm/s, 95% CI -0.45 to 0.08, p = 0.176. Multivariate regression analysis showed that in the PXG patients the PSV and EDV in the CRA were significantly positively correlated with the mean defect (p = 0.006 and 0.002 respectively). The RI in the CRA was significantly negatively correlated with the mean defect in PXG patients, p = 0.009. CONCLUSION: The results of this study showed that the retrobulbar hemodynamics might be disturbed in patients with PXG, especially in the central retinal artery. Our results have found no significant differences in the retrobulbar hemodynamic parameters between pseudoexfoliative syndrome patients and age-matched healthy subjects.  相似文献   

5.
BACKGROUND: In the pathophysiology of open-angle glaucoma altered perfusion of the optic nerve head is of importance. Up to now these disturbances were presumed to be the chief cause of glaucomatous damage in patients with normal tension glaucoma showing other vascular disturbances like migraine or tinnitus. PATIENTS AND METHODS: Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured and the resistive index (RI) was calculated by colour Doppler imaging (CDI) in the ophthalmic artery (OA), central retinal artery (CRA) and in the short and long posterior ciliary arteries (SPCA, LPCA) in 18 patients with normal tension glaucoma (NTG), in 18 patients with high tension glaucoma (HTG) and in 18 normal control subjects. RESULTS: In an upright sitting position both glaucoma groups showed statistically significant decreases in PSV and EDV in CRA and SPCA compared to the control subjects. HTG when compared to NTG and normal subjects showed statistically significant decreases of EDV and statistically significant increases of RI in LPCA. In addition, compared to normal subjects, HTG patients showed statistically significant increases of RI in both OA and SPCA. DISCUSSION: Both glaucoma groups showed decreased blood flow velocities in the small retrobulbar vessels in an upright sitting position. Normal tension glaucoma patients with symptoms of vasospasms compared to patients with high tension glaucoma showed only small differences in ocular haemodynamics.  相似文献   

6.
OBJECTIVE: To compare the retrobulbar haemodynamic parameters in the ophthalmic artery (OA) and short posterior ciliary arteries (SPCA) in pseudoexfoliative and primary open-angle glaucoma patients. SUBJECTS AND METHODS: Fourty-three eyes from 43 patients with pseudoexfoliative glaucoma (PXE) and 31 eyes from 31 patients with primary open-angle glaucoma (POAG) who met the inclusion/exclusion criteria were included in this prospective cross-sectional study. Colour Doppler imaging measurements, peak systolic velocity (PSV), and end-diastolic velocity (EDV) were assessed in the OA and posterior ciliary arteries (PCA). Pourcelot resistivity indices (RI) were calculated. Visual function was assessed using the 24-2 Swedish Interactive Threshold Algorithm (SITA). The main outcomes of the study were PSV, EDV, and RI in the OA and SPCA. RESULTS: In POAG patients, PSV and EDV were significantly lower in the OA, P=0.003 and P<0.001 respectively, and in the PCA, P=0.003 and P<0.001 respectively, when compared with the PXE group. The RI was significantly higher, P<0.001, in both vessels, in the POAG group. CONCLUSION: The results of this study have found reduced PSV and EDV and increased RI in the retrobulbar vessels of POAG patients when compared with PXE patients.  相似文献   

7.
AIM: To investigate the relation between blood flow parameters of the retrobulbar vessels measured by means of colour Doppler imaging (CDI) and fluorescein filling defects of the optic nerve head in patients with normal tension glaucoma (NTG) and control subjects. METHODS: 29 patients with NTG and 29 age and sex matched control subjects were included in this study. Blood flow velocities-peak systolic velocity (PSV), end diastolic velocity (EDV), and resistive indices (RI) of the ophthalmic artery (OA), the central retinal artery (CRA), and of the temporal and nasal short posterior ciliary arteries (TPCA, NPCA)-were measured with CDI. Fluorescein angiograms were performed with a scanning laser ophthalmoscope. The extent of absolute fluorescein filling defects of the optic nerve head in relation to the optic nerve head was assessed. RESULTS: The PSV of the OA, the PSV and EDV of the CRA, and of the TPCA and NPCA were significantly reduced in NTG (p<0.05). The RI of the CRA, the TPCA and NPCA were significantly increased in NTG (p<0.01). The optic nerve head fluorescein filling defects were significantly larger in NTG (p<0.01). The filling defects were significantly negatively correlated (p<0.05) with the PSV and EDV of the CRA (PSV(CRA): r = -0.41; EDV(CRA): r = -0.34), with the PSV and EDV of the NPCA (PSV(NPCA): r = -0.34; EDV(NPCA): r = -0.38), and with the EDV of the TPCA (r = -0.29). A significant positive correlation (p<0.05) was found with the RI of both PCAs (RI(NPCA): r = 0.28; RI(TPCA): r = 0.29). CONCLUSION: Patients with NTG had reduced blood flow velocities and higher resistive indices in most retrobulbar vessels. Optic nerve head fluorescein filling defects were larger compared to controls. The filling defects were correlated with end diastolic velocities and resistive indices of the PCAs and with blood flow velocities of the CRA. Capillary loss of the optic nerve head may be related to higher downstream resistance and reduced blood flow velocities of the retrobulbar vessels.  相似文献   

8.
Purpose To investigate interocular differences in retrobulbar flow velocities in patients with asymmetric glaucomatous visual field loss.Methods Twenty-five patients with primary open-angle glaucoma (POAG) and asymmetric visual field loss were included in this study. Asymmetric visual field loss was defined as a difference of the global index mean deviation (MD) >6 dB between the two eyes. Flow velocities (peak systolic velocity PSV and end-diastolic velocity EDV) and resistive indices (RI) of the ophthalmic artery (OA), central retinal artery (CRA), and nasal and temporal posterior ciliary arteries were measured by means of colour Doppler imaging.Results MD of eyes with more severe glaucomatous visual field loss was −18.3±7.8 dB vs −6.8±5.5 dB (p<0.0001) in the less affected eyes. The PSV and the EDV of the CRA and the PSV of the OA were significantly decreased in eyes with more severe glaucomatous visual field loss (CRA PSV: 7.6±2.0 cm/s vs 8.3±1.7 cm/s, p=0.04; CRA EDV: 2.24±0.5 cm/s vs 2.55±0.6 cm/s, p<0.007; OA PSV: 29.7±9.9 cm/s vs 32.7±11.5 cm/s, p<0.02). None of the other differences in velocity or resistive index were significant.Conclusions Patients with asymmetric glaucomatous visual field loss exhibit asymmetric flow velocities of the CRA and OA. Patients with more severe damage display reduced flow velocities in retrobulbar vessels in POAG.  相似文献   

9.
BACKGROUND/AIMS: Autoregulation of blood flow during posture change is important to ensure consistent organ circulation. The purpose of this study was to compare the change in retrobulbar ocular blood flow in glaucoma patients with normal subjects during supine and upright posture. METHODS: 20 open angle glaucoma patients and 20 normal subjects, similar in age and sex distribution, were evaluated. Blood pressure, intraocular pressure, and retrobulbar blood velocity were tested after 30 minutes of sitting and again after 30 minutes of lying. Retrobulbar haemodynamic measures of peak systolic velocity (PSV), end diastolic velocity (EDV), and resistance index (RI) were obtained in the ophthalmic and central retinal arteries using colour Doppler imaging (CDI). RESULTS: When changing from the upright to supine posture, normal subjects demonstrated a significant increase in OA EDV (p = 0.016) and significant decrease in OA RI (p = 0.0006) and CRA RI (p = 0.016). Glaucoma patients demonstrated similar changes in OA measures of EDV (p = 0.02) and RI (p = 0.04), but no change in CRA measures. CONCLUSION: Glaucoma patients exhibit faulty autoregulation of central retinal artery blood flow during posture change.  相似文献   

10.
Purpose: To evaluate the ocular blood flow velocities and haemorheological parameters in patients with primary open‐angle glaucoma (POAG), exfoliative glaucoma (XFG) and exfoliation syndrome (XFS) and to compare their results with those of healthy controls. Methods: Twenty‐five patients with POAG (group 1), 25 patients with XFG (group 2), 25 patients with XFS (group 3) and 25 healthy controls (group 4) were included in the study. Ocular blood flow velocities of ophthalmic artery (OA), central retinal artery (CRA) and short posterior ciliary arteries (SPCAs) were measured using colour Doppler imaging (CDI). Haemorheological parameters (erythrocyte elongation and aggregation index, aggregation amplitude, aggregation half‐life, plasma viscosity, haematocrit) were measured in venous blood samples of all patients. Results: The peak systolic velocity (PSV) and end‐diastolic velocity (EDV) values were lower and resistive indices (RI) were higher for the OA, CRA and SPCA of glaucomatous (groups 1 and 2) patients compared with those of controls (group 4) (PSV: OA, 40.4 ± 11.3 versus 52.6 ± 12.8 cm/second, p < 0.001; CRA, 12.9 ± 2.9 versus 15.3 ± 4.2 cm/second, p = 0.02; SPCA, 21.7 ± 6.6 versus 26.6 ± 8.3 cm/second, p = 0.013) (EDV: OA, 10.3 ± 4.3 versus 14.2 ± 5.1 cm/second, p < 0.001; CRA, 3.7 ± 1.1 versus 4.5 ± 1.3 cm/second, p = 0.025; SPCA, 5.2 ± 1.8 versus 7.7 ± 3.2 cm/second, p = 0.001) (RI: OA, 0.75 ± 0.05 versus 0.66 ± 0.07, p < 0.001; CRA, 0.73 ± 0.08 versus 0.68 ± 0.10, p = 0.223; SPCA, 0.70 ± 0.10 versus 0.63 ± 0.11, p = 0.004). There were no statistically significant differences between the haemorheological parameters of glaucomatous and non‐glaucomatous patients. The reduction in ocular blood flow velocities in groups 1, 2 and 3 were not associated with changes in haemorheological parameters. Conclusion: Our results suggest that impairment of the retrobulbar blood flow in POAG and XFG is not associated with alterations in haemorheological parameters.  相似文献   

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