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Glaucoma Patients (glaucoma + patient)
Kinds of Glaucoma Patients Selected AbstractsAutonomic dysfunction in unselected and untreated primary open angle glaucoma patients: a pilot studyOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 4 2007Doina Gherghel Abstract Purpose:, To investigate the presence of silent cardiac ischaemic episodes and the status of autonomic function in consecutive, newly diagnosed and untreated primary open-angle glaucoma patients. Methods:, Twenty-four consecutively diagnosed glaucoma patients and 22 age-matched controls were subjected to ambulatory 24-h blood pressure (BP) and electrocardiogram (ECG) monitoring by using Cardiotens-01 (Meditech Ltd). Based on the ECG recordings, heart rate variability (HRV) frequency domain parameters [low-frequency (LF), high-frequency (HF) and LF/HF ratio] were calculated and analysed in the two study groups. Results:, Glaucoma patients demonstrated higher LF and LF/HF values than normal subjects for both the active period (p = 0.020 and 0.029) and the passive period (p = 0.044 and 0.049 respectively). HRV parameters were similar in patients and controls suffering from silent cardiac ischaemia (p > 0.05); however, glaucoma patients with normal ECG demonstrated higher LF and LF/HF values during the active period of the 24-h measurement period than control subjects characterized by the same cardiac activity (p = 0.010 and 0.021 respectively). Conclusion:, Independent of a history and/or clinical signs of cardiovascular disease, glaucoma patients exhibit abnormal autonomic function. [source] Evaluation of some factors affecting the agreement between the Proview Eye Pressure Monitor and the Goldmann applanation tonometer measurementsCLINICAL AND EXPERIMENTAL OPTOMETRY, Issue 4 2007Pinakin Gunvant BS Optom PhD FAAO Background:, Our aim was to examine whether training level and ocular factors could account for part of the difference in intraocular pressure (IOP) measured using the Goldmann applanation tonometer (GAT) and Proview Eye Pressure Monitor (PPT). Methods:, One hundred and nineteen individuals (238 eyes) were enrolled in the study. The mean age was 35.8 years (range 21 to 79). All study participants obtained IOP measurements using the PPT after hearing instructions on how to perform PPT. Glaucoma patients obtained additional IOP measurements using PPT after viewing an instructional video and after 30 days of home use. IOP was also measured using the GAT at each experimental session. Results:, The difference in IOP measured by the GAT and the PPT was 0.55 ± 3.38 mmHg, 0.17 ± 3.79 mmHg and -1.30 ± 3.79 mmHg for myopic, emmetropic and hypermetropic groups, respectively, which were statistically significant (ANCOVA; p = 0.014). The difference in IOP between GAT and PPT was not significantly different for measurements obtained after verbal instructions, instructional video or after 30 days of home use (Repeated-ANCOVA; p = 0.30). The overall agreement between the GAT and the PPT was poor. Intra-class correlation coefficient was 0.575, and the 95% confidence interval (CI) of agreement was -6.93 to +6.73 mmHg. Conclusion:, There was a small systematic difference in IOP measured by the GAT and PPT when comparing the different refraction groups; however, this level of difference between the groups is unlikely to be of clinical significance. The level of training in using the PPT did not influence its measurements. The limits of agreement between the PPT and the GAT were wide and long-term use of PPT did not improve its agreement. [source] Measuring visual diasability in glaucomaACTA OPHTHALMOLOGICA, Issue 2009A KOTECHA Quantification of the visual disability experienced by the glaucoma patient is currently limited to the use of clinician-based measures of disease status; that is, measurement of retinal nerve fibre layer thickness, visual field sensitivity and intraocular pressure. However, whilst these tests provide information to the clinician regarding patient management requirements, they provide very little information about the patient's ability to function on a day-to-day basis. There have been attempts to measure the glaucoma patient's experience using vision-specific ,quality of life' questionnaires. However, it is apparent that no two patients with the same disease status will report the same quality of life experience. The purpose of this talk is to present new work examining how glaucoma patients perform specific, day-to-day tasks in the presence of the disease, with a view to understanding what specific visual factors might explain the difficulties they encounter at different stages of the disease. [source] Novel mutations in the MYOC/GLC1A gene in a large group of glaucoma patients,,HUMAN MUTATION, Issue 6 2002Karin Michels-Rautenstrauss Abstract Mutations at the myocilin (MYOC) gene within the GLC1A locus have been revealed in 2-4% of patients suffering primary open angle glaucoma (POAG) worldwide. In our ongoing glaucoma study sixhundred eighty two persons have been screend for MYOC mutations. The first group consisted of 453 patients from a long-term clinical study diagnosed either with juvenile OAG (JOAG), POAG, ocular hypertension (OHT) or normal tension glaucoma (NTG) plus 22 cases of secondary glaucoma. This group, and additional 83 healthy controls, is part of a long term study with repeated clinical examinations at the University of Erlangen-Nurnberg. An additional sample of 124 glaucoma patients or at risk persons referred from other sources were included in the mutation screening. Five novel mutations, namely Gly434Ser, Asn450Asp, Val251Ala, Ile345Met and Ser393Asn, could be identified as cause of preperimetric POAG, JOAG, normal tension POAG and POAG. Myocilin mutations were identified similar with previous reports with other ethnic populations at the rate of 11/341 (3.2%) probands. © 2002 Wiley-Liss, Inc. [source] Observer experience improves reproducibility of color doppler sonography of orbital blood vesselsJOURNAL OF CLINICAL ULTRASOUND, Issue 6 2002János Németh MD Abstract Purpose. The study investigated the reproducibility of orbital blood flow measurements with color Doppler imaging (CDI) at different stages of observer experience. Methods. The subjects were 31 healthy volunteers and 2 sequential groups of 25 glaucoma patients each. Repeated blood flow measurements (usually 3 sets) in orbital vessels (ophthalmic artery, short posterior ciliary arteries, central retinal artery, and central retinal vein) were performed by the same observer in a single session in each subject. Results. The parameters with the best reproducibility were the resistance index (mean coefficient of variation [COV], 3.3,8.8%), the peak systolic velocity (mean COV, 6.9,13.7%), the time-averaged velocity (mean COV, 7.2,16.0%), and the systolic acceleration time (mean COV, 8.8,12.3%). The mean COV was greater (9.9,20.3%) for the other arterial flow parameters (end-diastolic velocity and systolic acceleration) and for the venous flow velocities (maximum and minimum). The COVs of the parameters were improved by 20,40% as the observer became more experienced in ophthalmic CDI. Conclusions. We confirm the general reliability of CDI measurements in orbital vessels and show that observer experience improves reproducibility. It appears, however, that observer performance in these measurements is vessel specific. © 2002 Wiley Periodicals, Inc. J Clin Ultrasound 30:332,335, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/jcu.10079 [source] How good are we at advising appropriate patients with glaucoma to inform the DVLA?OPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 4 2008A closed audit loop Abstract Purpose:, To establish how good we are as clinicians at advising glaucoma patients with bilateral visual field defects of their legal responsibility to inform the Driver and Vehicle Licensing Agency (DVLA). By using a sticker placed in the patients' notes to highlight driving status and visual fields, we sought to improve our success in providing and documenting this advice. Methods:, We interviewed and examined the notes of two groups of 100 consecutive glaucoma patients before and after the introduction of a ,driver sticker' placed into patients' notes at the time of visual field testing. We examined the documentation of driving status, and the provision and documentation of advice regarding the DVLA. Results:, In the first audit, we found only 9% of patients had driving status documented. Only 20% of drivers with bilateral field defects were advised to inform the DVLA with 11.4% documentation of this advice. After the introduction of the sticker, we succeeded in improving the documentation of driving status to 99%. We advised and documented the advice to inform the DVLA in 97% of drivers with bilateral field defects. Conclusions:, We found that as a unit we were poor at documenting driving status and advising glaucoma patients with bilateral field defects to inform the DVLA. By the simple measure of introducing a sticker into patients' notes, we were able to highlight this critical group and improve our provision and documentation of appropriate advice regarding informing the DVLA. [source] Autonomic dysfunction in unselected and untreated primary open angle glaucoma patients: a pilot studyOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 4 2007Doina Gherghel Abstract Purpose:, To investigate the presence of silent cardiac ischaemic episodes and the status of autonomic function in consecutive, newly diagnosed and untreated primary open-angle glaucoma patients. Methods:, Twenty-four consecutively diagnosed glaucoma patients and 22 age-matched controls were subjected to ambulatory 24-h blood pressure (BP) and electrocardiogram (ECG) monitoring by using Cardiotens-01 (Meditech Ltd). Based on the ECG recordings, heart rate variability (HRV) frequency domain parameters [low-frequency (LF), high-frequency (HF) and LF/HF ratio] were calculated and analysed in the two study groups. Results:, Glaucoma patients demonstrated higher LF and LF/HF values than normal subjects for both the active period (p = 0.020 and 0.029) and the passive period (p = 0.044 and 0.049 respectively). HRV parameters were similar in patients and controls suffering from silent cardiac ischaemia (p > 0.05); however, glaucoma patients with normal ECG demonstrated higher LF and LF/HF values during the active period of the 24-h measurement period than control subjects characterized by the same cardiac activity (p = 0.010 and 0.021 respectively). Conclusion:, Independent of a history and/or clinical signs of cardiovascular disease, glaucoma patients exhibit abnormal autonomic function. [source] A double masked placebo controlled study on the effect of nifedipine on optic nerve blood flow and visual field function in patients with open angle glaucomaBRITISH JOURNAL OF CLINICAL PHARMACOLOGY, Issue 2 2001Georg Rainer Aims, To investigate whether nifedipine affects ocular perfusion or visual fields in open angle glaucoma patients. Methods, In a parallel group study nifedipine or placebo was administered for 3 months (n = 30). Ocular fundus pulsation amplitude (FPA), cup blood flow (Flowcup) and visual field mean deviation (MD) were measured. Results, Five patients receiving nifedipine discontinued due to adverse events. Nifedipine did not affect FPA [difference: 0.3 µm (95% CI ,0.3,0.9); P = 0.70], Flowcup: [difference: ,9 rel.units (95% CI ,133,114); P = 0.99], or MD [difference: 0.2dB (95% CI ,2.2,2.7); P = 0.51]vs placebo. Conclusions, Systemic nifedipine is not well tolerated in glaucoma patients and exerts no effect on visual fields or ocular perfusion. [source] 2224: Oxygenation of the human retinaACTA OPHTHALMOLOGICA, Issue 2010E STEFANSSON Purpose Partial pressure of oxygen in the optic nerve and retina is regulated by the intraocular pressure and systemic blood pressure, the resistance in the blood vessels and oxygen consumption of the tissue. The PO2 is autoregulated and moderate changes in intraocular pressure, blood pressure or tissue oxygen consumption do not affect the retinal and optic nerve oxygen tension. Methods If the intraocular pressure is increased above 40 mmHg or the ocular perfusion pressure decreased below 50 mmHg the autoregulation is overwhelmed and the optic nerve becomes hypoxic. The levels of perfusion pressure that lead to optic nerve hypoxia in the laboratory correspond remarkably well to the levels that increase the risk of glaucomatous optic nerve atrophy in human glaucoma patients. Medical intervention can affect optic nerve PO2. Lowering the intraocular pressure tends to increase the optic nerve PO2, even though this effect may be masked by the autoregulation when the optic nerve PO2 and perfusion pressure is in the normal range. Results Carbonic anhydrase inhibitors increase retinal PO2 through a mechanism of vasodilatation and lowering of the intraocular pressure. Carbonic anhydrase inhibition reduces the removal of CO2 from the tissue and the CO2 accumulation induces vasodilatation resulting in increased blood flow and improved oxygen supply. This effect is inhibited by indomethacin but not other cyclo-oxygenase inhibitors. Conclusion Carbonic anhydrase inhibitors increase retinal blood flow and increase oxygen delivery. Glaucoma drugs and glaucoma surgery lower intraocular pressure, increase ocular perfusion pressure and blood flow. Demand of oxygen by retinal cells may be reduced through apoptosis and tissue atrophy, as well as active destruction of tissue by laser photocoagulation. [source] 2153: Can we treat glaucoma by non-IOP related approaches?ACTA OPHTHALMOLOGICA, Issue 2010I STALMANS Intra-ocular pressure is the main risk factor for the progression of glaucoma. However, intra-ocular pressure lowering is not always sufficient to halt the progressive ganglion cell loss. Indeed, additional risk factors have been identified for glaucoma progression that can explain why some patients progress despite rigourous intra-ocular pressure lowering. Vascular risk factors, such as low perfusion pressure, can be taken into account in the management of our glaucoma patients. The treatment options for these vascular risk factors will be discussed during the lecture. Moreover, neuroprotective strategies might open therapeutic perspectives to directly support the ganglion cells and thus help stabilizing the disease. Possible neuroprotective agents will be highlighted. [source] 3253: Ocular neurovascular coupling in glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2010K GUGLETA Purpose Defining property of glaucoma, cupping of the optic disc in parallel to loss of retinal ganglion cells and their axon, implies tissue remodeling of the optic nerve head which in turns requires involvement of astrocytes. Their malfunction may lead not only to cupping, but also to disturbance in ocular neurovascular coupling. Methods We analyzed 122 glaucoma patients, ocular hypertensives and healthy controls who all received no IOP-lowering therapy at least four weeks prior to the study examination. One eye per subject entered the primary analysis: in the POAG group, an eye with the biggest damage, in the OHT group an eye with the highest average IOP was selected. Relative vessel diameter increase in response to flicker light was used as the measure of neurovascular coupling. Results This response was impaired in untreated POAG patients, affecting both superior and inferior temporal retinal vessels. In general, inferior vessel dilated more than superior ones. The dilation amplitude was inversely correlated to the level of morphological (retinal nerve fiber layer thickness) and functional (visual field mean defect) glaucomatous damage. Despite the relatively high level of inter- and intraocular correlation of vessel responses, in a separate analysis of contralateral eyes, they seem to display higher dilation amplitudes than the more damaged eyes which were included in the original analysis. Conclusion Neurovascular coupling is impaired in untreated glaucoma patients. Prospective studies are underway in an attempt to clarify the cause versus consequence relationship between the glaucomatous damage and disturbance of neurovascular coupling. [source] 3254: Neurovascular coupling in the retrobulbar ciliary circulationACTA OPHTHALMOLOGICA, Issue 2010O ZEITZ Purpose Perfusion of the retina is adapted to the metabolic demand by neurovascular coupling. Neurovascular coupling has shown to be present in the retinal vasculature, but not in vessels supplying the optic nerve. The present study investigated the presence of neurovascular coupling in the anterior part of the optic nerve in healthy and glaucoma subjects. Methods Retrobulbar blood flow velocities were determined by color Doppler imaging (CDI). A Siemens Elegra ultrasound system with a 7.5L40 transducer was used. Peak-systolic and end-diastolic velocities (PSV and EDV) in the central retinal artery (CRA) or the short posterior ciliary artery (SPCA) were the primary readout. CDI measurements were performed shortly before, during, immediately after, 60 s after, and 120 s after a 10-Hz flicker stimulation of the retina. Results Thirty-five glaucoma patients and 44 healthy control subjects were included in the study. In the SPCA of healthy controls, flicker stimulation led to a rise of PSV from 9.7±0.8 to 12.5±0.8 cm/s (P<0.001; N=24) and of EDV from 2.4±0.3 to 3.6±0.3 cm/s (P<0.001; N=24). This effect was not detectable in glaucoma patients. In the CRA, flicker light led to an increase of EDV from 2.1±0.2 to 3.0±0.3 cm/s (P=0.002; N=20) in healthy volunteers and from 1.3±0.2 to 2.0±0.2 cm/s in glaucoma patients (P=0.004; N=15). PSV was affected by flicker stimulation in neither the healthy volunteers nor glaucoma patients. Conclusion The data indicate the presence of neurovascular coupling in the vascular bed supplied by the paraoptic SPCA. The response pattern to the flicker stimulus differs between healthy and glaucoma subjects. [source] 2164: Role of placental growth factor (PIGF) in wound healing after glaucoma filtration surgeryACTA OPHTHALMOLOGICA, Issue 2010T VAN BERGENArticle first published online: 23 SEP 2010 Purpose Failing filtering surgery due to excessive wound healing is a considerable challenge in ophthalmology, and largely contributes to progressive vision loss in glaucoma patients. Anti-VEGF therapy helps to prevent post-surgical scarring by inhibiting angiogenesis and collagen deposition, but does not influence inflammation (which is also an important player in postoperative wound healing). We will check the hypothesis that placental growth factor (PlGF) plays a role in scar formation after glaucoma filtration surgery, and that it may be a(n) (additional) target for improvement of the outcome of this surgery through its known anti-angiogenic and anti-inflammatory, and possibly anti-fibrotic properties. Methods The effect of an anti-PlGF antibody (ThromboGenics) will be investigated in vitro on the proliferation of endothelial cells (HUVEC), inflammatory cells (Jurkat cells) and of Tenon fibroblasts (TF). The effect of the antibody will also be investigated in vivo in a rabbit model for glaucoma surgery by measuring intra-ocular pressure (IOP), filtration bleb function and survival, and by (immuno-)histological analysis of angiogenesis (CD31), inflammation (CD45) and fibrosis (Sirius Red). Conclusion Our proposed research project will elucidate the potential role of PlGF-inhibition in the improvement of filtration surgery outcome, and will highlight any angiostatic, anti-inflammatory, and/or anti-fibrotic effects. PlGF-inhibition as an adjuvant anti-inflammatory therapy to anti-VEGF treatment in glaucoma surgery might open new perspectives for more efficient surgery. In conclusion, our project opens exciting perspectives for the treatment of the blinding condition of glaucoma, and thus might improve the visual prognosis of glaucoma patients. [source] 2134: Arachnoid cell changes following elevated pressure and oxidative stress: new implications for optic nerve degenerationACTA OPHTHALMOLOGICA, Issue 2010A NEUTZNER Purpose The study of meningothelial cells (MCs) and their connection to optic nerve function. MCs line the arachnoid layer of the meninges and form a barrier between the CSF and the blood circulation. A previous study revealed a significantly increased proliferation of MCs in the arachnoid surrounding the optic nerve glaucoma patients. Methods To explore a possible role of these cells in the pathogenesis of diseases of the optic nerve, we studied the effect of elevated hydrostatic pressure and oxidative stress on MCs using rotenone to inhibit mitochondrial function and compared them to untreated control cells. Cell viability and proliferation were measured using a MTS-based assay. As a measure of barrier function, we assessed the endocytotic activity of MCs by fluorescence and confocal microscopy following fluorescent-latex bead uptake. Results Exposure of MCs to elevated hydrostatic pressure caused significant cellular proliferation and a dramatic decrease in endocytotic activity. Furthermore, mild oxidative stress severely inhibited endocytosis, thus negatively impacting MC barrier function. Conclusion MCs surround the optic nerve, thereby shielding it from but also conditioning the microenvironment of this sensitive area. As elevated pressure and oxidative stress occur in patients with increased intracranial pressure who have papilledema and probably in some cases of normal-tension glaucoma, these phenomena may impact the function of MCs and thus, contribute to the loss of retinal ganglion cells in the course of these and, perhaps, other optic nerve diseases. [source] 2127: Ghrelin concentration in the aqueous humour and plasma in open angle glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2010A KATSANOS Purpose Ghrelin is a peptide hormone that exerts metabolic and smooth muscle-relaxant effects in ocular tissues. The aim of this study was to compare aqueous humor and plasma levels of ghrelin in patients with open angle glaucoma (OAG) and controls. Methods Twenty four OAG, including 7 pseudoexfoliation (PXG) and 17 primary open-angle glaucoma (POAG) patients, and 30 controls were included. All participants were patients scheduled for cataract or glaucoma surgery. Patients with other concomitant ocular disease, previous ocular surgery or diabetes were excluded. Blood samples were collected before cataract surgery. Aqueous humor was aspirated from the anterior chamber through a paracentesis with a 27 G needle under sterile conditions. Ghrelin levels in both samples were measured quantitatively with commercially available Radioimmunoassay (RIA) kits. Results Mean±SD age was 71.0±9.3 and 69.6±6.6 years in the OAG and control groups, respectively (p=0.6). Plasma levels of ghrelin were 495.6±157.7 pg/ml in the OAG and 482.2±125.4 pg/ml in the control group, respectively (Mann-Whitney test, p=0.9). Aqueous humor levels of ghrelin were 85.5±15.4 pg/ml and 123.4 ±25.5 pg/ml in the OAG and control groups, respectively (Mann-Whitney test, p<0.01). The ratio of plasma/aqueous concentration in ghrelin was higher in the OAG versus the control group (5.82± 1.94 versus 4.00±1.04, Mann-Whitney test, p<0.01). There was no difference neither in plasma nor in aqueous humor levels of ghrelin between POAG and PXG patients (p>0.5). Conclusion Aqueous humor levels of ghrelin were significantly lower in OAG patients. This difference may manifest a role of ghrelin in the disease process or a consequence of antiglaucoma treatment. [source] 2352: The influence of central corneal thickness and corneal biomechanics in glaucomaACTA OPHTHALMOLOGICA, Issue 2010FC LAM Purpose To look at the impact that central corneal thickness and corneal biomechanics can have on intraocular pressure (IOP) measurements and their effect on visual fields. Methods Written and informed consent from patients and guidance from the local research ethics committee was obtained. Ocular diagnoses and ocular medications were recorded. IOPs were recorded using Goldmann applanation tonometry (GAT)followed by dynamic contour tonometry with the Pascal tonometer. Central corneal thickness(CCT) was measured using ultrasound. Visual fields were recorded using Humphries perimetry. Bland-Altman plots were used to compare the 2 methods. Results 92 eyes of 46 patients were included. Median CCT 556µm(range:427µm-634µm). Despite a good correlation of the IOP measurements usin the two different techniques(r=0.7; p< 0.01), there was a significant difference in limits of agreement(LOA) of DCT to GAT on the Bland-Altman analysis. The LOA was 8.6mmHg to -4.8mmHg with a mean bias of 1.9mmHg. This persisted even after correction for CCT. Ocular hypertensives had a wider LOA than glaucoma patients. Conclusion DCT IOP measurements can be significantly different from GAT IOPs even after taking into account central corneal thickness. Compared to CCT, corneal hysteresis appears to have a greater impact on IOP measurements. This could have important prognostic implications. [source] 2353: The influence of corneal thickness and curvature on IOP measurement by IcareTM rebound tonometer and applanation tonometry in glaucoma patients and normal subjects.ACTA OPHTHALMOLOGICA, Issue 2010P KRZYZANOWSKA-BERKOWSKA Purpose To evaluate the influence of central corneal thickness (CCT) and radius of the corneal curvature (R) on IOP measurements obtained with the ICare rebound tonometer and the Goldmann applanation tonometer (GAT). Methods Eighty four eyes of 48 subjects (65 eyes of glaucoma patients and 19 eyes of healthy volunteers) were examined with ICare and Goldmann tonometers. Central corneal thickness was determined by ultrasound pachymetry. Corneal radius of curvature was determined using corneal topography. Results There was no significant difference between IOP readings with ICare and GAT. Intraocular pressure measurements were found to be higher with the ICare tonometer, both in glaucoma patients (15,3±4,0 mmHg) and normal subjects (14,4±3,0 mmHg). ICare-GAT mean difference was 1.1±3.6mmHg (95% CI, -6.1-8.3mmHg) for glaucoma patients and 1.8±3.2mmHg (95% CI, -4.6-8.2mmHg) for healthy volunteers. Using CCT patients were divided into 2 groups: 1) thinnest corneas - CCT<556 ,m (mean CCT 531±23 ,m), 39 eyes and 2) thickest corneas - CCT >556 ,m (mean CCT 578±17 ,m), 45 eyes. In the group of thinnest corneas there was no correlation between IOP, CCT and R. In thickest corneas there was significant correlation between IOP readings obtained by ICare and CCT (r=-0.4, p<0.01), and mean radius (R) (r=0.5, p<0.001). Conclusion Measurements of IOP using the ICare rebound tonometer are in good agreement with Goldmann applanation tonometer in glaucoma patients and normal subjects, although influenced by CCT. [source] 2356: Diurnal variation of ocular pulse amplitude in primary open angle glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2010LA PINTO Purpose (1) to determine the diurnal behaviour of the ocular pulse amplitude (OPA) in primary open angle glaucoma (POAG) patients. (2) To identify any variables modulating OPA. Methods In this prospective study we included 22 POAG patients under topical intraocular pressure (IOP)-lowering treatment, who underwent contour dynamic tonometry measurements every three hours from 9am to 6pm for IOP and OPA readings. Heart rate (HR) and blood pressure (BP) were simultaneously recorded during the ocular measurements. Only the eye with greater glaucomatous damage was selected per patient. Results Both IOP and OPA did not change during the day (OPA: 3.0±1.3, 3.2±1.4, 2.9±1.5, 3.0±1.3; IOP: 19.3±2.9, 20.0±3.0, 19.1±3.0, 19.8±2.6; multiple comparisons p=0.21, p=0.27 respectively). Systolic, diastolic and did not present significant diurnal variation (p<0.05 all measurements). OPA was significantly correlated at all time-measurements with arterial pulse pressure, but not by IOP, median ocular pulse pressure(MOPP) nor median arterial pressure (p<0.05). Univariate analysis revealed HR to negatively correlate OPA at the 15h and 18h measurements (r= -0,42, p=0.049; r= -0,53, p=0.01; respectively). Multiple linear regression analysis identified blood pressure amplitude as an independent factor contributing to OPA (p<0.05 at all measurements). These observations were more pronounced in patients with high blood pressures. Conclusion OPA readings seem to be influenced by blood pressure amplitude in POAG patients. High blood pressure amplitude values may overcome the eye self-regulation mechanisms, resulting in the OPA becoming dependent on the blood pressure amplitude rather than of the IOP. [source] 2357: Autonomic nervous system and endothelial peripheral dysfunction in normal tension glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2010J WIERZBOWSKA Purpose To define parameters of autonomic nervous system activity and peripheral vascular reactive hyperemia in normal tension glaucoma patients. Methods Ambulatory 24-hour electrocardiogram and blood pressure (BP) monitoring by using Lifecard CF and SpaceLab 90207-30 combined with occlusion provocation test were carried out in 54 NTG patients (44 women, mean age 59.7) and 43 matched control subjects (34 women, mean age 57.0). Heart rate variability (HRV) time and frequency domain parameters [low-frequency (LF), high-frequency (HR) and LF/HF ratio], and blood pressure variability (BPV) were calculated and analyzed for both study groups. Postocclusive hyperemia response parameters (TM - time to peak flow, TH ,half-time hyperaemia, TR ,time to rest flow, BZ-biological zero and MAX , maximum hyperemic response) were compared for patients with a nocturnal fall in mean BP (MPB) of less than 10% (non-dippers), of 10-20% (dippers) and of more than 20% (over-dippers) Results NTG patients demonstrated higher LF and LF/HF values for 24-hour period, day-time and night time than control subjects. There was no difference in BPV between study groups (10.4 ± 1.9 vs. 10.5 ± 2.1, p=0.790). In NTG patients, TH was significantly higher (79.0 ± 80.9 s vs. 51.5 ± 35.3 s, p=0.028) and BZ was significantly lower (2.3 ± 1.0 vs. 3.1 ± 2.0, p=0.009) as compared to the control group. There was statistically significant difference between NTG non-dippers, dippers and over,dippers in the BZ parameter (2.3 ± 0.9 vs. 2.7 ± 1.3 vs. 1.4 ± 0.4 p=0.024). Conclusion NTG patients exhibit abnormal ANS system activity and a different systemic hyperemia response as compared with healthy subjects. [source] 4354: Relationship between flicker FDF perimetry and standard automated perimetryACTA OPHTHALMOLOGICA, Issue 2010P CALVO PEREZ Purpose To compare the main indices of flicker FDF perimetry (FDF, Heidelberg Engineering, Germany) with standard automated perimetry (SAP). Methods Twenty healthy subjects and twenty-three glaucoma patients were prospectively and consecutively selected. Glaucomatous patients had an intraocular pressure higher than 21 mmHg and glaucomatous optic disc appearance. All of them underwent at least one reliable perimetry with each device. SAPs were performed with a FDF perimeter (24-2 ASTA-Standard test) and Humphrey perimeter (Carl Zeiss (24-2 SITA standard algorithm). The Kolmogorov Smirnov test was applied to check that the data were normally distributed. Only one eye per subject was included in the study. Pearson correlations were calculated between both devices : mean deviation (MD), pattern standard deviation (PSD), and visual field index (VFI). Results Mean age was 58.41±12,4 years. MD of SAP was -2.82 ± 4.8 dB, and MD of FDF was -4.47 ± 4.8 dB (p=0.123); PSD of SAP was 3.11 ± 3.1, and PSD of FDF was 3.14 ± 1.4 (p = 0.953). The correlations between MDs were 0.521 (p<0.001) and between PSDs were 0.350 (p<0.001) Conclusion Moderate correlations were found between main visual field indices both devices. Altough no differences were found, FDF tends to present MD values lower than Humphrey. [source] The effect of deep sclerectomy on intraocular pressure of normal-tension glaucoma patients: 1-year resultsACTA OPHTHALMOLOGICA, Issue 1 2010Sakari Suominen Abstract. Purpose:, To study the intraocular pressure (IOP)-reducing effect of deep sclerectomy on normal-tension glaucoma (NTG) patients. Methods:, We retrospectively analysed 21 eyes of 18 consecutive NTG patients who had undergone deep sclerectomy with mitomycin-C and a collagen implant. Results:, Median (range) preoperative IOP was 15.1 mmHg (9.3,20.8) and median follow-up time 13 months (12,18). At the 1-year follow-up visit, median IOP was significantly (P < 0.001) reduced to 10.5 mmHg (4,15) with median IOP reduction from preoperative values of 37% (12,78). Laser goniopuncture was performed in 10 eyes (48%) 1,16 months postoperatively. After 13 months' follow-up, a complete success at 20%, 25% and 30% IOP reduction levels was achieved in 67%, 62% and 52% of eyes, respectively. Few complications were encountered, but these included reduced visual acuity, problems with conjunctiva, microperforation, hyphaema, Dellen formation and encapsulated bleb. We encountered no complications related to postoperative hypotony. Conclusion:, Deep sclerectomy with a collagen implant and mitomycin-C was a safe and effective method for reducing IOP in NTG patients during 1-year follow-up. [source] Machine learning classifiers for glaucoma diagnosis based on classification of retinal nerve fibre layer thickness parameters measured by Stratus OCTACTA OPHTHALMOLOGICA, Issue 1 2010Dimitrios Bizios Abstract. Purpose:, To compare the performance of two machine learning classifiers (MLCs), artificial neural networks (ANNs) and support vector machines (SVMs), with input based on retinal nerve fibre layer thickness (RNFLT) measurements by optical coherence tomography (OCT), on the diagnosis of glaucoma, and to assess the effects of different input parameters. Methods:, We analysed Stratus OCT data from 90 healthy persons and 62 glaucoma patients. Performance of MLCs was compared using conventional OCT RNFLT parameters plus novel parameters such as minimum RNFLT values, 10th and 90th percentiles of measured RNFLT, and transformations of A-scan measurements. For each input parameter and MLC, the area under the receiver operating characteristic curve (AROC) was calculated. Results:, There were no statistically significant differences between ANNs and SVMs. The best AROCs for both ANN (0.982, 95%CI: 0.966,0.999) and SVM (0.989, 95% CI: 0.979,1.0) were based on input of transformed A-scan measurements. Our SVM trained on this input performed better than ANNs or SVMs trained on any of the single RNFLT parameters (p , 0.038). The performance of ANNs and SVMs trained on minimum thickness values and the 10th and 90th percentiles were at least as good as ANNs and SVMs with input based on the conventional RNFLT parameters. Conclusion:, No differences between ANN and SVM were observed in this study. Both MLCs performed very well, with similar diagnostic performance. Input parameters have a larger impact on diagnostic performance than the type of machine classifier. Our results suggest that parameters based on transformed A-scan thickness measurements of the RNFL processed by machine classifiers can improve OCT-based glaucoma diagnosis. [source] Ocular blood flow and oxygen delivery to the retina in primary open-angle glaucoma patients: the addition of dorzolamide to timolol monotherapyACTA OPHTHALMOLOGICA, Issue 1 2010Brent Siesky Abstract Purpose:, To assess the effects of adding dorzolamide to timolol monotherapy on ocular haemodynamics and retinal oxygen saturation in patients with primary open-angle glaucoma (POAG). Methods:, Twenty-four patients (12 healthy, 12 with POAG) were treated with dorzolamide/timolol combination (DT) versus timolol maleate 0.5% twice daily in a randomized, crossover, double-blind study conducted over a period of 18 months. Patients received each treatment for 8 months then crossed over to the other treatment after a 1-month washout and second baseline. Goldmann applanation tonometry, Heidelberg retinal flowmetry (HRF), colour Doppler imaging (CDI) and retinal photographic oximetry were performed at each visit. Results:, DT significantly reduced intraocular pressure (IOP) in both glaucomatous [right eye (OD) ,13.15%, left eye (OS) ,14.43%; p < 0.036] and non-glaucomatous (OD ,12.4%, OS ,13.88%; p < 0.039) patients compared to timolol after 8 months of treatment. DT significantly reduced the number of zero blood flow pixels in the superior (,39.72%; p < 0.014) and inferior (,51.44%; p < 0.008) retina in the non-glaucomatous group and inferior retina in the glaucomatous group (,55.38%, p < 0.006). The continuation of timolol monotherapy from baseline did not change (p < 0.05) any measured parameter and neither treatment had a significant effect (p < 0.05) on retinal oximetry or CDI parameters. Conclusion:, The addition of dorzolamide to timolol monotherapy decreases IOP and increases retinal blood flow in the superficial retinal vasculature in both glaucomatous and healthy patients following 8 months of treatment. The combination of increased retinal blood flow with consistent oxygen saturation may potentially increase oxygen delivery to the retina. [source] The need and total cost of Finnish eyecare services: a simulation model for 2005,2040ACTA OPHTHALMOLOGICA, Issue 8 2009Anja Tuulonen Abstract. Purpose:, The aims of this study were: (i) to create a structural simulation model capable of predicting the future need and cost of eyecare services in Finland; and (ii) to test and rank different policy alternatives for access to care and the required physician workforce. Methods:, Using the system dynamics approach, the number and cost of patients with cataract, glaucoma, diabetic retinopathy and age-related macular degeneration (AMD) were described with causal-loop diagrams and were then translated into a set of mathematical equations to build a computer simulation model. Mathematically, the problem was formulated as a set of differential equations that were solved numerically with specialized software. The validity of the model was tested against prevalence and administrative historical data. The costs covered by the public sector in Finland were obtained from 2003 from the Finnish Hospital Discharge Register (including outpatient care), the Finnish Social Insurance Institution and a survey of hospital price lists. Different levels of access to public care were then simulated in four eye diseases, for which the model estimated the need for services and resources and their costs in the years 2005,2040. Results:, The model forecasted that the adoption of the 2005 national ,access to care' criteria for cataract surgery would shorten waiting lists. If the workload of Finnish ophthalmologists were kept at the 2003 level, the graduation rate of new ophthalmologists would have to increase by 75% from the current level. If all glaucoma patients were followed in the public sector in future, even this increase in training would not meet the demand for physician workforce. The current model indicated that the screening frequency of diabetes can be increased without large sacrifices in terms of costs. AMD therapy has a significant role in the allocation of future resources in eyecare. The modelling study predicted that ageing alone will increase the costs of eyecare during the next four decades in Finland by about 1% per year in real terms (undiscounted and without inflation of unit costs). The increases in total yearly costs were on average 8.6% between 2001 and 2003. Conclusions:, The results of this modelling study indicate that policy initiatives, such as defining criteria for access to care, can have substantial implications on the demand for care and waiting times whereas the effect of ageing alone was relatively small. Measures to control several other factors , such as the adoption and price level of new technologies, treatments and practice patterns , will be at least equally important in order to restrain healthcare costs effectively. [source] Association between corneal hysteresis and central corneal thickness in glaucomatous and non-glaucomatous eyesACTA OPHTHALMOLOGICA, Issue 8 2009George Mangouritsas Abstract. Purpose:, We aimed to determine corneal hysteresis values (CH) using the ocular response analyser (ORA) in non-glaucomatous and glaucomatous eyes and their relationship with central corneal thickness (CCT). Methods:, Corneal hysteresis, intraocular pressure (IOP) as measured by Goldmann applanation tonometry (GAT) and CCT were prospectively evaluated in 74 non-glaucoma subjects with IOP < 21 mmHg and in 108 patients with treated primary open-angle glaucoma (POAG). One eye in each subject was randomly selected for inclusion in the analysis. Results:, Mean (± standard deviation [SD]) age was 59.2 ± 14.2 years in the non-glaucoma group and 62.4 ± 9.8 years in the glaucoma group. Mean (± SD) GAT IOP was 15.7 ± 2.65 mmHg and 16.38 ± 2.73 mmHg in the non-glaucoma and glaucoma groups, respectively. There was no statistically significant difference between the two groups in mean age (p = 0.396) or mean GAT IOP (p = 0.098). Mean (± SD) CH was 10.97 ± 1.59 mmHg in the non-glaucoma and 8.95 ± 1.27 mmHg in the glaucoma groups, respectively. The difference in mean CH between the two groups was statistically significant (p < 0.0001). There was a strong positive correlation between CH and CCT in the non-glaucoma group (r = 0.743) and a significantly (p = 0.001) weaker correlation (r = 0.426) in the glaucoma group. Conclusions:, Corneal hysteresis was significantly lower in eyes with treated POAG than in non-glaucomatous eyes. The corneal biomechanical response was strongly associated with CCT in non-glaucoma subjects, but only moderately so in glaucoma patients. It can be assumed that diverse structural factors, in addition to thickness, determine the differences in the corneal biomechanical profile between non-glaucomatous and glaucomatous eyes. Corneal hysteresis could be a useful tool in the diagnosis of glaucoma. [source] Measuring visual diasability in glaucomaACTA OPHTHALMOLOGICA, Issue 2009A KOTECHA Quantification of the visual disability experienced by the glaucoma patient is currently limited to the use of clinician-based measures of disease status; that is, measurement of retinal nerve fibre layer thickness, visual field sensitivity and intraocular pressure. However, whilst these tests provide information to the clinician regarding patient management requirements, they provide very little information about the patient's ability to function on a day-to-day basis. There have been attempts to measure the glaucoma patient's experience using vision-specific ,quality of life' questionnaires. However, it is apparent that no two patients with the same disease status will report the same quality of life experience. The purpose of this talk is to present new work examining how glaucoma patients perform specific, day-to-day tasks in the presence of the disease, with a view to understanding what specific visual factors might explain the difficulties they encounter at different stages of the disease. [source] What do patients with glaucoma do when they search and look at everyday scenes?ACTA OPHTHALMOLOGICA, Issue 2009ND SMITH Purpose To test the hypothesis that patients with bilateral glaucoma exhibit different eye movements compared to normally-sighted subjects when viewing computer displayed photographs, or searching for features or items within them. Methods Thirteen glaucoma patients and 17 age-matched subjects with normal vision viewed 28 randomised digital photographs of various everyday scenes displayed on a computer screen for 3 seconds each. Subjects were instructed to view the images as they would when looking at a slideshow. The subjects then viewed another set of images, but were timed to find a feature or item in the scene. Eye movements were simultaneously recorded using an Eyetracking system. Results In the passive viewing experiment, there was a significant reduction in the average number of saccades for glaucoma patients compared to controls (p<0.0001). In addition, average fixation duration was longer and the average area scanned was more restricted in patients compared to controls. In the search task glaucoma patients took, on average, longer to find the objects (p<0.0001) compared to controls. For this task, saccades were still reduced in number. In some cases, individual scanning patterns appeared related to the type and nature of the binocular visual field defect. Conclusion Eye movement behaviour in patients with glaucomatous defects in both eyes differ from normal-sighted subjects when viewing images and photographs. These patients with glaucoma find it more difficult to locate items within scenes compared to normally sighted subjects. Acknowledgements: This work is generously supported by an unrestricted grant from the Special Trustees of Moorfields Eye Hospital. [source] Fitness to drive in glaucoma patients- Preliminary study resultsACTA OPHTHALMOLOGICA, Issue 2009AM STEVENS Purpose To develop a useful binocular 30° visual field criterion to predict safe driving behaviour in glaucoma patients by comparing perimetric data with an actual driving test on the road. Methods The sample will consist of 200 driving glaucoma patients, recruited in 2 university based glaucoma clinics (Ghent and Leuven, Belgium). Inclusion criteria are glaucomatous optic disc damage and/or glaucomatous field defects. Exclusion criteria are concomitant ocular disease, cataract > LOCS 2, systemic disease or medication affecting the visual field. Data collection will include demographic and medical data, driving habits, and Mini Mental Status. A complete ophthalmic examination wil be done including Goldmann, SAP and Esterman visual field testing. In addition, UFOV test, stereopsis and contrast sensitivity testing will be performed. All subjects will perform an on the road driving test with a driving expert of the Belgian Institute for Traffic Safety. Subjects can pass, fail, or pass the test with limitations. An attempt will be made to develop an algorithm of visual field abnormalities that predict as accurately as possible the outcome of the practical driving test. Results Preliminary results of the first 50 included patients will be presented. [source] Evidence for altered ocular rigidity in glaucomaACTA OPHTHALMOLOGICA, Issue 2009L SCHMETTERER Purpose Based on theoretical models and animal studies altered biomechanical properties of the optic nerve head and the sclera have been implicated in the pathophysiology of glaucoma. Only few data have, however, demonstrated such biomechanical alterations in vivo. We tested the hypothesis that patients with primary open angle glaucoma (POAG) have an abnormal structural stiffness based on measurements of intraocular pressure amplitude and ocular fundus pulsation amplitude. Methods Seventy patients with POAG and 70 healthy control subjects matched for age, gender, intraocular pressure and systemic blood pressure were included in this study. The ocular pulse amplitude (PA) was assessed with pneumotonometry. The fundus pulsation amplitude (FPA) was measured using laser interferometry. Based on the Friedenwald equation a coefficient of structural stiffness (E1) was calculated relating PA to FPA. Results Systemic blood pressure, intraocular pressure, and ocular perfusion pressure was comparable between glaucoma patients and healthy control subjects. FPA as well as PA was lower in patients with glaucoma than in healthy controls. The calculated factor E1 was significantly higher in patients with POAG (0.0454 ± 0.0085 a.u.) than in healthy control subjects (0.0427 ± 0.0058 a.u., p = 0.03). Conclusion This study is indicative of increased structural stiffness of the sclera in patients with POAG. This is in agreement with a number of previous animal experiments and supports the idea that the biomechanical properties of ocular tissues play a role in the process of glaucomatous ONH damage. [source] Ocular pulse amplitude under pressure: what happens to OPA in glaucoma before and after surgery?ACTA OPHTHALMOLOGICA, Issue 2009I STALMANS Purpose To investigate whether trabeculectomy, besides its intraocular pressure (IOP) - lowering effect, has an effect on the ocular pulse amplitude (OPA). To determine if OPA changes are influenced by IOP changes. Methods Forty-eight glaucoma patients (48 eyes) scheduled for unilateral first-time trabeculectomy were prospectively enrolled from October 2007 to April 2008. The eye undergoing trabeculectomy was considered as study eye, whereas the non-operated fellow eye was used as control eye. OPA, IOP, blood pressure and heart rate were measured prior to and 4 weeks following trabeculectomy by means of Pascal dynamic contour tonometry (DCT), Goldmann applanation tonometry (GAT) and sphygmomanometry. A regression model for repeated measures was used. Results Preoperative GAT, DCT and OPA were 20.92 ±8.55 mmHg, 21.33 ±7.06 mmHg and 3.23 ±1.58 mmHg, respectively. One month following trabeculectomy, GAT, DCT and OPA were 11.23 ±5.03 mmHg, 14.45 ±4.79 mmHg and 2.12 ±1.07 mmHg, respectively. There was a significant decrease in OPA after filtering surgery in the study eye compared to the control eye (P<0.0001). Changes in OPA were correlated with changes in IOP (Spearman rho = 0.49, P=0.0004). When the IOP change caused by filtering surgery was taken into account, no significant difference in effect on the OPA following trabeculectomy could be demonstrated in the study eye compared to the control eye (P=0.18). Conclusion OPA changes were strongly correlated with IOP changes. There was no evidence for an effect of filtering surgery on the OPA when the concomitant IOP decrease after trabeculectomy was taken into account. [source] | ||||||||||