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Unaffected Eyes (unaffected + eye)

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Medical Sciences	100%

Selected Abstracts

Colour Doppler imaging evaluation of blood flow parameters in the ophthalmic artery in acute and chronic phases of optic neuritis in multiple sclerosis

ACTA OPHTHALMOLOGICA, Issue 1 2009
Pavel Hradílek
Abstract. Purpose:, Optic neuritis (ON) is a common manifestation of multiple sclerosis (MS). It is caused by the immune-mediated inflammation of the optic nerve. Some vascular factors that may influence blood flow in the ophthalmic artery (OA) have also been suggested as factors in the pathogenesis of ON. The purpose of our study was to evaluate blood flow velocities and resistance (RI) and pulsatile (PI) indices in the OA in both orbits in patients in the acute and chronic phases of unilateral ON and to compare these with equivalent findings in healthy control subjects. Methods:, Orbital colour Doppler imaging (CDI) was performed in 40 consecutive MS patients during acute unilateral ON prior to corticosteroid treatment. Optic neuritis was diagnosed on the basis of clinical presentation and facultative assessment of visual evoked potentials (VEPs). The peak systolic (PSV) and end-diastolic (EDV) velocities and RI and PI were measured in the OA in both eyes. We compared results from affected and unaffected orbits using the paired t -test. The same measurements were performed in 114 MS patients with a history of acute unilateral ON that occurred > 1 year prior to ultrasound examination. We also measured the same parameters in the middle cerebral arteries (MCAs) on both sides in all subjects in both groups. The same measurements were obtained in healthy controls. Results:, The PSV (p < 0.0001), RI (p < 0.0001) and PI (p < 0.0001) in the OA in the eye affected with acute ON were significantly higher than in the unaffected eye. There was no difference in EDV in the OA between affected and unaffected eyes (p > 0.05) in the group with acute ON. We did not observe any significant differences between eyes in either blood flow velocities or the RI or PI (p > 0.05) in the group in the chronic phase of ON or in the control group. All the parameters in the MCAs on both sides were normal in both the acute and chronic groups, as well as in the control group. Conclusions:, Pathophysiological changes during acute unilateral ON influence orbital haemodynamics, as is indicated by increased PSV, RI and PI in the OA in eyes affected with ON. However, these changes do not persist over longer periods. [source]

Toward a practical protocol for human optic nerve DTI with EPI geometric distortion correction

JOURNAL OF MAGNETIC RESONANCE IMAGING, Issue 4 2009
Udomchai Techavipoo PhD
Abstract Purpose To develop a practical protocol for diffusion tensor imaging (DTI) of the human optic nerve with echo planar imaging (EPI) geometric distortion correction. Materials and Methods A conventional DTI protocol was modified to acquire images with fat and cerebrospinal fluid (CSF) suppression and field inhomogeneity maps of contiguous coronal slices covering the whole brain. The technique was applied to healthy volunteers and multiple sclerosis patients with and without a history of unilateral optic neuritis. DTI measures and optic nerve tractography before and after geometric distortion correction were compared. Diffusion measures from left and right or from affected and unaffected eyes in different subject cohorts were reported. Results The image geometry after correction closely resembled reference anatomical images. Optic nerve tractography became feasible after distortion correction. The diffusion measures from the healthy volunteers were in good agreement with the literature. Statistically significant differences were found in the fractional anisotropy and orthogonal eigenvalues between affected and unaffected eyes in optic neuritis patients with poor recovery. The diffusion measures before and after geometric distortion correction were not significantly different. For cohorts without optic neuritis, the difference between diffusion measures from left and right eyes was not statistically significant. Conclusion The proposed technique could provide a practical DTI protocol to study the human optic nerve. J. Magn. Reson. Imaging 2009;30:699,707. © 2009 Wiley-Liss, Inc. [source]

Reaction time during semi-automated kinetic perimetry (SKP) in patients with advanced visual field loss

ACTA OPHTHALMOLOGICA, Issue 1 2010
Katarzyna Nowomiejska
Abstract. Purpose:, This study aimed to evaluate reaction time (RT) in patients with advanced visual field (VF) loss using semi-automated kinetic perimetry (SKP). Methods:, Seventy-eight patients with advanced VF loss caused by glaucoma (31) or retinitis pigmentosa (19), homonymous VF loss caused by post-chiasmal lesions (18) and unilateral anterior ischaemic optic neuropathy (AION) (10) were examined with SKP (Octopus 101 perimeter). One eye in each patient was enrolled. Additionally, VFs in the 10 healthy fellow eyes of the patients with AION were compared with those in the 10 affected eyes. Reaction time was assessed during the SKP session by presenting kinetic stimuli (III4e) with constant angular velocities of 3 °/second moving linearly along so-called ,RT vectors' at four different locations inside the III4e isoptre. Each stimulus presentation was repeated four times in randomized order. Results:, The geometric mean RT was 794 ms (95% reference interval [RI] 391,1615 ms) in patients with glaucoma, 702 ms (95% RI 306,1608 ms) in patients with retinitis pigmentosa and 675 ms (95% RI 312,1460 ms) in patients with hemianopia. Increases in RT for every 1 ° of eccentricity were 1%, 0.9% and 0.4%, respectively. The geometric mean RT in the 10 patients with unilateral optic neuropathy was 644 ms in affected eyes and 435 ms in unaffected eyes, reflecting an increase of 51% (95% confidence interval 42,62%). Conclusions:, We found substantial inter-subject variability in RT in patients with advanced VF loss. It is possible to correct the position of the isoptres by assessing individual RT. There were no relevant differences in RT between the disease groups. Reaction time increases with eccentricity. In monocular disease (AION), RT is prolonged, compared with in healthy fellow eyes. However, in clinical routine the RT-related displacement of isoptres is negligible in the vast majority of cases. [source]

Colour Doppler imaging evaluation of blood flow parameters in the ophthalmic artery in acute and chronic phases of optic neuritis in multiple sclerosis

Ultrasound biomicroscopy of zonular anatomy in clinically unilateral exfoliation syndrome

ACTA OPHTHALMOLOGICA, Issue 5 2008
Zaher Sbeity
Abstract. Purpose:, To evaluate the ability of ultrasound biomicroscopy (UBM) to detect abnormalities in the zonular apparatus in unaffected eyes of patients with clinically unilateral exfoliation syndrome (XFS) using a standardized grading system. Methods:, The affected and unaffected eyes of 17 patients with clinically unilateral XFS and 17 eyes of 17 control subjects underwent UBM. Radial sections detailing the lens and zonules at 12:00, 1:30, 3:00, 4:30, 6:00, 7:30, 9:00 and 10:30 clock hours were obtained. The images were graded by a masked, experienced UBM observer using a standardized scoring system based on the zonular appearance (0, none; 1 and 2, uneven or disrupted zonules with or without patchy deposits; 3, diffuse granulation, thick zonules or both; 4, total zonular disruption). Affected meridians were compared by the Friedman test, while distributions of unaffected and affected eyes were compared using the Student t -test. Results:, In the control group, 15/17 eyes showed normal zonules; the remaining two eyes showed grade 1 changes in some meridians. The mean grade score was 0.33 [standard deviation (SD) 0.84]. Eyes with XFS had a higher score than control eyes, with a mean score of 14.35 (SD 7.14, P < 0.001, Student t -test). In clinically unaffected fellow eyes, the mean score was 10.53 (SD 7.44), and was less than that of XFS eyes (P = 0.008, Student t -test). Twelve XFS eyes (71%) and six unaffected fellow eyes (35%) had grade 3 or 4 in at least one meridian (P = 0.07, Friedman test). Conclusion:, Bilateral zonular involvement is present in subjects with clinically unilateral XFS. These zonular changes may be extensive in fellow eyes without clinically evident exfoliation material. UBM assessment of zonular status in fellow eyes prior to cataract extraction may aid in surgical planning. [source]

Retinal nerve fibre layer of perimetrically unaffected eyes of glaucoma patients: an optical coherence tomography study

CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 2 2009
Stefano Da Pozzo MD PhD
Abstract Purpose:, The aim of this study is to evaluate whether optical coherence tomography (StratusOCT) may detect early changes in perimetrically unaffected (PU) fellow eyes of glaucomatous patients by assessing retinal nerve fibre layer (RNFL) thickness parameters. Methods:, Thirty-seven glaucomatous patients with unilateral field loss and 34 age-matched controls were recruited. In glaucoma patients, PU and perimetrically affected fellow eyes were analysed separately. For each group, mean values (±SD) of RNFL thickness parameters were calculated and comparisons between fellow eyes of glaucoma patients and between healthy and PU eyes of glaucoma patients conducted with paired t -test and Mann,Whitney U -test, respectively. Proportion of clock-hour sectors flagged with probability <5% or <1% was collected and differences between healthy and PU eyes were evaluated on Fisher exact test. Results:, Global (Average Thickness) and sectoral parameters (Inferior and Nasal Average), Maximum thickness,minimum thickness (Max-min), as well as 2-o'clock (nasal side) and 6-o'clock sectors resulted significantly thinner in PU eyes than in control group. Proportion of eyes with clock-hour position flagged with probability <5% or <1% was not significantly different between healthy and PU eyes. Conclusion:, Despite a standard automated perimetry within normal limits, the StratusOCT detected both localized and diffuse RNFL thinning in PU eyes of glaucoma patients. These eyes should be considered at risk of developing functional damage over time and consequently require thorough monitoring for detecting any sign of progression. [source]

Multifocal objective perimetry compared with Humphrey full-threshold perimetry in patients with optic neuritis

CLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 6 2006
Nima Pakrou MBBS(Hons)
Abstract Background:, The aim of the study is to compare multifocal visual evoked potential (mfVEP) objective perimetry with Humphrey full-threshold visual field (HVF) perimetry, in the assessment of patients with optic neuritis (ON). Methods:, We assessed 16 patients with clinically diagnosed ON. A comparison was made between the HVF and mfVEP, based on the global severity indices of both tests and number and topography of significant abnormalities detected. The latency data and inter-eye asymmetry findings on the mfVEP were also evaluated. Results:, From a total of 128 quadrants analysed in the 16 patients (100 affected, 28 unaffected eyes), HVF perimetry identified a scotoma in 39/128 (30.5%) quadrants, all of which were in affected eyes; the mfVEP detected a scotoma in 68/128 (53.1%) quadrants using amplitude and/or asymmetry data (XV2 = 7.2485, P = 0.0071). Latency plots on the mfVEP identified a significant latency deviation cluster in 20/25 (80%) affected eyes. Abnormalities were also detected in 4/7 (57%) unaffected eyes. The global severity indices in the affected eyes showed a high correlation between the two tests (r = 0.73). Conclusions:, The mfVEP detected more abnormalities in patients with ON than HVF perimetry. The use of latency recordings as well as combined amplitude and asymmetry plots is advantageous and has the potential to detect abnormalities not otherwise detected on HVF perimetry. [source]