Changes in the retrobulbar hemodynamic parameters after decreasing the elevated intraocular pressure in primary open-angle glaucoma patients.

INTRODUCTION: Ocular blood flow (OBF) disturbances could be involved both in the pathogenesis and in progression of glaucomatous damage. OBJECTIVE: The aim of the study was to compare the retrobulbar hemodynamic parameters in the ophthalmic artery (OA), central retinal artery (CRA) and short posterior cilliary arteries (SPCA) after decreasing the elevated intraocular pressure (IOP) in primary open-angle glaucoma (POAG) patients by using color Doppler imaging (CDI). METHODS: We examined 60 patients (21 male and 39 female) with diagnosed and treated POAG. Thirty-nine patients had increased IOP (> 25 mm Hg). Peak-systolic velocity (PSV), end-diastolic velocity (EDV), Pourcelot resistance index (RI), and pulsatility index (PI) were assessed in the OA, CRA, and SPCA. IOP was measured both with the Goldmann Applanation tonometer (GAT) and with the Dynamic Contour tonometer (DCT), three times respectively. Ocular pulse amplitude (OPA) was measured using DCT. RESULTS: The retrobulbar parameters between the baseline and after IOP reduction showed no difference in measurements. After Bonferroni correction (p < or = 0.0056, alpha/9) statistical significance was recorded only in the following retrobulbar hemodynamic parameters; DCT (29.8 +/- 6.2 vs. 15.5 +/- 5.0), GAT (33.8 +/- 9.0 vs. 15.0 +/- 6.6) and OPA measurements (4.3 +/- 1.0 vs. 3.0 +/- 1.6), as compared to the baseline. There was no correlation between the changes in IOP measured with either DCT or GAT and changes in the hemodynamic parameters (p > 0.05 for all). Pearson correlation coefficient (95% CI) showed very good correlation for IOP measurements between DCT and GAT: at baseline 0.83 (0.71 to 0.90) and at the end 0.71 (0.55 to 0.83); p < 0.0001 for both measurements, but without any difference between them (p > 0.05). CONCLUSION: There was a lack of correlation between the changes in IOP measured with either DCT or GAT and the changes in the hemodynamic parameters.

Changes in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure in men and women with primary open angle glaucoma.

INTRODUCTION: An altered perfusion of the optic nerve head has been proposed as a pathogenic factor of glaucoma. OBJECTIVE: The aim of this study was to evaluate the changes of the hemodynamic parameters in the retrobulbar arterial circulation after decrease of the elevated intraocular pressure (IOP) in women and men with primary open angle glaucoma. METHODS: The study included 60 patients (33 males and 27 females) older than 50 years, with diagnosed and treated primary open angle glaucoma (77 eyes of 39 patients had increased IOP, > 25 mm Hg).They were examined at the Clinic of Eye Diseases (complete ophthalmologic exam) and Clinic of Neurology, Clinical Center of Serbia, Belgrade, from December 2009 to December 2010. Imaging of hemodynamic parameters of three retrobulbar arterial vessels: ophthalmic, central retinal and posterior ciliary arteries with color Doppler was performed. RESULTS: Among women, hemodynamic arterial parameter of the peak-systolic velocity was increased in the central retinal artery and decreased in the ophthalmic artery and posterior ciliary arteries; end-diastolic velocity was increased in all three retrobulbar vascular levels; Pourcelot resistivity index was increased, but pulsatility index was decreased in all three vessels. Among men, peak-systolic velocity, end-diastolic velocity and pulsatility index were decreased in all three vessels; resistivity index was increased in the ophthalmic artery, but decreased in the central retinal artery and posterior ciliary arteries. There was a significant change of the ophthalmic artery pulsatility index in women, and the end-diastolic velocity of the ophthalmic artery in men. CONCLUSION: There was a difference of the retrobulbar arterial circulation between women and men with primary open angle glaucoma after decrease of the elevated intraocular pressure.The role of vascular factors in the supply of the optic disc neuroretinal rim is important.

Correlation between ocular pulse amplitude measured by dynamic contour tonometer and colour Doppler flow imaging of the arteric retrobulbar vessels.

INTRODUCTION: An altered perfusion of the optic nerve head has been proposed as a pathogenic factor in glaucoma. OBJECTIVE: The aim of this study was to evaluate the correlation between ocular pulse amplitude (OPA), measured by Dynamic contour tonometer (DCT) and colour Doppler imaging (CDI) of the arteric retrobulbar vessels. METHODS: Twenty patients older than 50 years were examined, and divided into two equal groups. The first group comprised of patients with normal tension glaucoma treated with topical antiglaucomatous therapy, and the second group included patients with ocular hypertension and glaucoma suspicious without any antiglaucomatous therapy. Ocular pulse amplitude (OPA) was measured with DCT. CDI was also performed. We measured haemodynamic parameters of the internal carotid artery (ICA), ophthalmic artery (OA), central retinal artery (CRA), and posterior ciliary arteries (PCA). Peak systolic (PSV), end-diastolic (EDV) velocities were measured, and resistance index (RI) and pulsatility index (PI) were calculated. RESULTS: Correlation with OPA showed indirect servitude in the RI of the ICA, RI and PI of the CRA, in the first group; and in the PSV and EDV of the ICA, in the RI and PI of the OA, EDV and RI of the CRA, and RI of the PCA, in the second group CONCLUSION: Increase of OPA was mostly followed by the increase of the parameters (PSV, EDV, RI, and PI) of the arteric retrobulbar vessels in the first group; in the second group, increase of OPA was in almost 50% of parameters followed by their decrease.

[Prevention of intraocular pressure elevation after argon laser trabeculoplasty in primary open angle glaucoma].

INTRODUCTION: Argon laser trabeculoplasty (ALT) is an intraocular pressure lowering method that is overall safe and powerful, but often complicated by transient postoperative intraocular pressure rises. In prevention of this complication, we frequently use two potent alpha-adrenergic agonists--brimonidine and apraclonidine. OBJECTIVE: The aim of this study was to compare brimonidine 0.2% and apraclonidine 0.5% efficacy and safety in prevention of intraocular pressure elevation after ALT. METHODS: This was a prospective, randomized, double-masked and comparative study. This study included 27 POAG patients, 15 received 0.2% brimonidine, and 12 received 0.5% apraclonidine before laser surgery (22 eyes in both groups). Intraocular pressure readings were taken 1, 2, 3, 24 hours and 7 days after ALT. Student's t-test was used to analyse data between two groups, and chi2 test to compare data within groups. Value p less than 0.05 was considered statistically significant. RESULTS: We found statistically significantly lower IOP in eyes that received 0.2% brimonidine at readings taken 1 hour after ALT (p = 0.001). There were no statistically significant differences in other IOP readings between two groups. CONCLUSION: A single preoperative drop of brimonidine 0.2% had similar efficacy and safety as apraclonidine 0.5% in preventing transient IOP elevations after ALT.

Changes in the retrobulbar arterial circulation after decrease of elevated intraocular pressue in patients with primary open angle glaucoma.

INTRODUCTION: An altered perfusion of the optic nerve head has been proposed as a pathogenic factor in glaucoma. OBJECTIVE: To evaluate changes of haemodynamic parameters in the retrobulbar arterial circulation after a decrease of elevated intraocular pressure (IOP) in patients with primary open angle glaucoma (POAG). METHODS: Twenty-six patients were examined, 14 men and 12 women, 21 up to 50 years old and 5 below, all with previously diagnosed and treated POAG, and all examined at the Eye Clinic, Clinical Centre of Serbia. IOP was measured both with a Goldmann aplanation tonometer and dynamic contour tonometer. Central corneal thickness was measured with ultrasound pachymeter. Imaging of the retrobulbar arterial circulation by colour Doppler was performed at the Neurology Clinic, Clinical Centre of Serbia. It involved measuring of haemodynamic parameters of the ophthalmic artery, central retinal artery, and posterior ciliary arteries. Peak systolic velocity (PSV) and end-diastolic velocity (EDV) were measured, and resistive index (RI) and pulsatility index (PI) were calculated. RESULTS: Haemodynamic arterial parameters PSV and EDV in the ophthalmic and central retinal artery after decrease of IOP were lower, while RI and PI were higher. In the posterior ciliary arteries PSV, EDV and PI were lower, and RI was higher. CONCLUSION: Changes of the retrobulbar arterial circulation after elevated LOP in POAG patients are important for approach and treatment, while the role of vascular factors in the supplement of the optic disc neuroretinal rim could be a key for progression backlash of glaucoma and the radix of neuroprotection.

Correlation between central corneal thickness and intraocular pressure in various age groups.

INTRODUCTION: The Pascal Dynamic Contour Tonometer (DCT) is an ophthalmic investigational device which directly calculates the dynamic pulsatile fluctuations in intraocular pressure (IOP) using a piezoelectric pressure sensor embedded in the devices tip. OBJECTIVE: The aim of this study was to compare IOP results obtained with Goldmann applanation tonometer (GAT), and their correlation with central corneal thickness (CCT) in patients of various age groups. METHODS: We studied 37 patients (17 male and 20 female), divided into three age groups: younger than 40 years; 40-60 years old, and older than 60 years. In the first and second group there were patients rarely and in the third mostly diagnosed and medicamentously compensated glaucoma. In topical anaesthesia, first we measured CCT, with ultrasound pachimeter, then IOP with DCT and GAT. RESULTS: Statistically significant difference between measurements of IOP with the DCT and GAT appeared in all groups: I mean diff. -1.71 +/- 1.27 mm; p < 0.0001; II mean diff. -1.19 +/- 1.06 mm; p < 0.0001; III mean diff. -1.69 +/- 1.67 mm; p < 0.0001. CCT was in indirect correlation with the values of IOP measured both with the DCT and GAT in the first and third, while it was in the direct correlation with these values in the second group. CONCLUSION: CCT had no influence on IOP measurements both with the DCT and GAT in none of the groups. The DCT cannot replace GAT, but it is a reliable device for the measurement of IOP particularly in corneal deformations (keratoconus, after corneal refractive surgery, corneal scars, etc.).

Topographic changes at the optic disc in 33 patients with primary open angle glaucoma / 国际眼科杂志(Guoji Yanke Zazhi)

AIM: To show frequency of progression and progres-sion at the optic disc in primary open angle glaucoma (POAG).METHODS: A total of 33 patients (66 eyes), 14 male and 19 female, aged 14 to 79 with POAG were imaged using the Heidelberg Retina Tomography II (HRT II) three or more times during follow-up periods of 6 years (2000-2006). Disc progression was determined by regression analysis of global and segmental changes in optic disc parameters. Every patient was tested by Octopus G1 once a year. Imaged optic disc parameters with scanning laser tomography were: rim area (ra), cup/disc (C/D), rim volume (rv), mean RNFL thickness (mRNFL). Imaged segments of the optic disc were: global (G), temporal (T), temporal superior (TS), temporal inferior (TI), nasal (N), nasal superior (NS) and nasal inferior (NI).RESULTS: Global frequency of progression according to c/d ratio existed in 34 eyes (51%), but 32 eyes (48%) were without frequency of progression. Progression existed in 12 eyes (18%) in temporal, 7 eyes (10.6%) in temporal superior (TS), 14 eyes (21%) in temporal inferior (TI), 8 eyes (12%) in nasal (N), 7 eyes (10.6%) in nasal superior (NS), and 13 eyes (20%) in nasal inferior (NI) segment. Without progression were 5 eyes (8%).CONCLUSION: Disc progression in our study was mostly in nasal (N) and temporal inferior (TI) segments. Most frequently were stricken temporal inferior (TI) and nasal inferior (NI), but most infrequently nasal superior (NS) segment. Most sensitive parameter was c/d ratio. Segmental scanning is of importance in POAG progression analysis.