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Field Defects (field + defect)
Kinds of Field Defects Selected AbstractsOcular complications of neurological therapyEUROPEAN JOURNAL OF NEUROLOGY, Issue 7 2005S. Hadjikoutis Treatments used for several neurological conditions may adversely affect the eye. Vigabatrin-related retinal toxicity leads to a visual field defect. Optic neuropathy may result from ethambutol and isoniazid, and from radiation therapy. Posterior subcapsular cataract is associated with systemic corticosteroids. Transient refractive error changes may follow treatment with acetazolamide or topiramate, and corneal deposits and keratitis with amandatine. Intraocular pressure can be elevated in susceptible individuals by anticholinergic drugs, including oxybutynin, tolterodine, benzhexol, propantheline, atropine and amitriptyline, and also by systemic corticosteroids and by topiramate. Nystagmus, diplopia and extraocular muscle palsies can occur with antiepileptic drugs, particularly phenytoin and carbamazepine. Ocular neuromyotonia can follow parasellar radiation. Congenital ocular malformations can result from in utero exposure to maternally prescribed sodium valproate, phenytoin and carbamazepine. Neurologists must be aware of potential ocular toxicity of these drugs, and appropriately monitor for potential adverse events. [source] The detection of small simulated field defects using multifocal VEPsOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2003H. L. Chan Abstract Introduction: The multifocal visual-evoked potential (mfVEP) has been widely investigated in the study of diseases of the visual system. However, the sensitivity of the mfVEP in objective detection of field defects has not been determined. This study investigates the variation of the mfVEP responses whilst simulating field defects by using different sizes of mask on the stimulus pattern. Methods: Simulated field defects of four different sizes (2, 3, 5, and 7 degrees) at two different eccentricities (10 and 16 degrees) were generated on a standard mfVEP dartboard stimulus using opaque masks. These masks were placed at the centre of each dartboard sector and the modified stimuli were used to elicit mfVEPs from 10 normal subjects. The response densities and latencies of N1, P1 of the mfVEP were compared, without and with small simulated field defects. Results: The minimum size of simulated field defect causing significant response density reduction in P1 and N1 was 5 degrees at both retinal eccentricities. N1 showed similar reduction in response density at both retinal eccentricities, but P1 showed larger reduction at the 10-degree location than at the 16-degree location. There was no change in latencies with simulated field defect at either location. Conclusions: The mfVEP is only sensitive to a simulated field defect equal to or larger than 5 degrees in diameter, and mfVEP has greater sensitivity at 10-degree eccentricity than at 16-degree eccentricity. [source] Post dural puncture headache in a pediatric patient with idiopathic intracranial hypertensionPEDIATRIC ANESTHESIA, Issue 9 2005OLUBUKOLA O. NAFIU MD FRCA Summary We describe the occurrence of postdural puncture headache (PPDH) in an adolescent with idiopathic intracranial hypertension (IIH) and its successful management with an epidural blood patch. PPDH is a very rare occurrence in patients with intracranial hypertension and is described as a paradoxical situation in the literature. There are only two previous case reports (in adults) of the possible association. A 15-year-old obese patient with a diagnosis of IIH had an uneventful diagnostic spinal tap using a 22G Quincke needle in the pediatric emergency department but returned 24 h later with PPDH. After a failed trial of conservative management, she had an uneventful but curative epidural blood patch with 15 ml of autologous venous blood and was able to return to school the day after the blood patch. Follow-up review by her neuro-ophthalmologist shows resolution of her headaches, considerable improvement in her visual field defect and resolution of papilledema. This is the first report of PPDH and its successful management with an epidural blood patch in a pediatric patient with IIH. [source] Acute visual loss after spinal surgeryACTA OPHTHALMOLOGICA, Issue 4 2010Jana Midelfart Hoff Abstract. Purpose:, To report visual loss after prone spinal surgery. Methods:, Computed tomography scan, fundus photography, optical coherence tomography (OCT). Results:, A 56-year-old man demonstrated loss of vision in the left eye after cervical spinal surgery. Clinical examination revealed loss of vision to finger counting, severe visual field defect and blurred neural rim area around the optic disc in the left eye. Six weeks later, visual acuity in the left eye was 6/9 and there was inferior visual field defect. Six months after the surgery, significant reduction of retinal nerve fibre layer thickness around the optic nerve head was measured with OCT, consistent with the visual field defect. Conclusion:, Ischemic optic neuropathy is the most common cause of visual loss after spine surgery and special emphasis should be given to protect the eye against possible pressure during the surgery. [source] The role of optical coherence tomography in the detection of pituitary adenomaACTA OPHTHALMOLOGICA, Issue 7 2009Charlotta Johansson Abstract. Purpose:, To analyse retinal nerve fibre layer (RNFL) thickness in eyes with compression of the optic chiasm by a pituitary adenoma. RNFL thickness was analysed with optical coherence tomography (OCT) and compared to visual field measurements using high-pass resolution perimetry (HRP). Methods:, Sixteen eyes from eight patients with pituitary adenoma were studied. All had bitemporal visual field depression caused by compression of the optic chiasm. Patients were submitted to an ophthalmic examination more than 14 months after surgery (seven patients had undergone trans-sphenoidal and one trans-cranial adenomectomy). The examination included HRP, fundus photography and measurement of the peripapillar RNFL thickness using OCT. Results:, In spite of temporal visual field depression, not all eyes showed reduced RNFL thickness by OCT. This was also true for some eyes in which RNFL was judged to be reduced on fundus photographs. Contrary to our expectations, RNFL thickness in the nasal quadrant was normal in nine of the 16 eyes. Corresponding figures for the superior, inferior and temporal quadrants were eight, six and five, respectively. The overall RNFL thickness, as measured by OCT, did not correlate well with neural capacity, which is an index of remaining retino-cortical neural channels in HRP. Conclusion:, RNFL thickness as measured with OCT was reduced in most, but not all, eyes with temporal field depression caused by chiasmal compression. The pattern of RNFL loss did not correlate well with the visual field defect. Sensitivity of RNFL thickness measurement in OCT was low. The method has limited value in the diagnosis of pituitary tumour compression. [source] Noninvasive oximetry and glaucomaACTA OPHTHALMOLOGICA, Issue 2009OB OLAFSDOTTIR Purpose To investigate retinal vessel oxygen saturation in relation to glaucomatous visual field damage. Specifically, we examined whether oxygen saturation in retinal blood vessels differs between regions corresponding to glaucomatous visual field defects compared to regions without visual field defects. Methods A spectrophotometric retinal oximeter (Oxymap ehf, Reykjavík, Iceland) was used to measure oxygen saturation in retinal arterioles and venules. The oximeter consists of a fundus camera, beam splitter, light filters and software that evaluate the oxygen saturation. The glaucomatous defect was estimated from a visual field test using the Octopus 1-2-3 perimeter. One eye in 13 individuals with open angle glaucoma with or without pseudoexfoliation syndrome was examined. Results In retinal areas with no visual field defect, the mean oxygen saturation in arterioles was 102±6% and 65±9%, (mean±SD) in venules. The arteriovenous difference was 37±10%. In retinal areas corresponding to visual field defects, the mean oxygen saturation in arterioles was significantly lower; 98±5% (p=0.04, paired t-test, n=13). The venules were at 68±7% (p=0.3) and the arteriovenous difference was also significantly lower; 30±10% (p=0.04). Conclusion Arteriolar oxygen saturation and arteriovenous difference is statistically lower in areas with visual field defects compared to areas without visual field defects. This data suggests that visual field defects are associated with a reduction in retinal oxygen delivery and metabolism. [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] Toxic effect of vigabatrin on retinal nerve fiber layerACTA OPHTHALMOLOGICA, Issue 2009A MIDELFART Purpose To investigate whether peripheral and central visual field defects detected among epilepsy patients treated with vigabatrin are associated with reduced peripapillary retinal nerve fiber layer thickness as measured with optic coherence tomography (OCT). Methods Nine epilepsy patients with vigabatrin-attributed visual field loss (group 1) and seven patients(age and sex matched) with epilepsy treated with other drugs(control group 2) were regularly examined with automated perimetry up to 60 degrees from fixation point (Humphrey Field Analyser). Peripapillary retinal nerve fiber layer thickness (RNFLT) was quantified by optic coherence tomography (OCT) using Fast RNFLT protocol, Stratus OCT (3.0). Five of the patients in group 1 had peripheral visual field defects, (group 1a), four had a central field defect(group 1b). All patients in control group 2 had normal visual field. Results Patients with vigabatrin-attributed visual field loss had attenuated total RNFLT compared to controls (right eye : mean total RNFLT: group 1: 75.6 µm (SD 12.7); group 2: 103.5 µm (SD 9.7), mean difference 27.9 µm (CI 15.9-39.9;P < 0.001). The nasal and inferior sectors RNFLT were more attenuated in patients with vigabatrin-attributed visual field loss compared to controls, while no difference was detected in the temporal RNFLT. Both individuals with peripheral and central visual field losses had attenuated mean total RNFLT compared to controls (P = 0.006 and P= 0.002, respectively). Conclusion Vigabatrin-attributed visual field defects are associated with reduced RNFLT. Combination of perimetry and OCT can efficiently detect vigabatrin induced retinal nerve fiber damage. [source] Tilted disc syndrome may mimic false visual field deteriorationACTA OPHTHALMOLOGICA, Issue 6 2008Marja-Liisa Vuori Abstract. Purpose:, Tilted disc syndrome is a congenital anomaly of the eye characterized by mostly upper temporal visual field defects. The aim of the present study was to evaluate the effect of gradual myopic correction in the improvement of visual field defects associated with tilted disc syndrome. Methods:, The visual field was examined in 38 eyes of 24 patients using standard Goldmann perimetry. The isoptres IV-4e, I-4e, I-3e and I-2e were plotted. The defective isoptres were tested again with gradually increasing myopic correction until no further change was noted. Results:, The most common type of defect was a relative upper temporal defect (19 eyes). Temporal relative defects were found in five eyes, upper altitudinal field defects in six eyes, an enlarged blind spot in four eyes, and an inferior field defect in one eye. The visual field defect partly or totally disappeared with increased myopic correction in 18 (50%) eyes. The mean improvement was 17.0 ± 6.2 degrees and the mean additional myopic correction was 3.1 ± 1.5 D. Conclusions:, Even a small change in near correction during visual field examination may imply worsened or improved visual field defects in tilted disc syndrome. To prevent a false interpretation of field deterioration in a patient with tilted disc syndrome and glaucoma, visual field assessment should include examination with the myopic correction that provides the maximal improvement of the defective visual field. [source] Cost-effectiveness analysis in glaucoma: what drives utility?ACTA OPHTHALMOLOGICA, Issue 3 2006Results from a pilot study in Sweden Abstract. Purpose:,To investigate the effect of different levels of visual field defect in glaucoma on utilities and to test if utilities could be assessed using a general questionnaire such as the EQ-5D. Methods:,A cross-sectional study in 199 patients with ocular hypertension or open-angle glaucoma grouped into 5 severity stages according to visual field defects was performed in 4 specialized ophthalmic centres. Descriptive analysis was performed for the sample and by stage, and the effect of vision loss on utility was investigated with multiple step-wise regression analysis. Results:,The mean age of the sample was 70 and the mean MD in the worse eye was ,13.1 dB (SD 10.2). Visual acuity (VA) was 0.63 and 0.87 in the worse and better eye, respectively, and the mean utility was 0.80 (SD 0.23). Utility decreased with increasing glaucomatous damage, ranging from 0.84 for mild disease to 0.72 for severe damage (MD ,2.5 to ,28.1), but the difference between the groups was not statistically significant when controlling for co-morbidity, except for the most severe stage (p < 0.01). In multiple regression analysis, visual field in the better eye was significantly correlated with utility, and there was an indirect correlation between visual field in the worse eye and utility: the effect of total VA on utility was significant, and MD in the worse eye was correlated with total VA. Conclusions:,Utility is strongly correlated with overall vision. Our results suggest a relationship between glaucomatous damage and utility, and patients with severe damage have a significantly lower utility. However, this should be further investigated in larger samples that include more patients with moderate-severe bilateral damage. [source] Craniopharyngioma: a review of long-term visual outcomeCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 3 2003Celia Chen MB BS MPHS Abstract Purpose: To assess the clinical presentation and long-term visual outcome in a series of patients with craniopharyn-gioma. Methods: Retrospective case review. Results: Thirty-six patients were reviewed, comprising 19 female patients and 17 male patients. The age range was 2,77 years with a bimodal distribution of 17 children (mean age 10 years) and 19 adults (mean age 47 years). Blurred vision was the most common visual complaint (23 cases, 64%) and headache the most frequent systemic complaint (19 cases, 53%). The average duration of systemic symptoms was 45 weeks compared to 10 weeks for visual symptoms. Deficits in visual acuity occurred in 13 patients (36%) and showed no significant change from initial presentation to final review. Sixteen patients (44%) had bitemporal hemianopia on presentation and pleomorphism (change from one type of visual field defect to another) occurred in 11 patients. Recurrence of tumour occurred in 15 patients (42%) and was more likely in children (59%) than adults (26%). The mean time period to recurrence was 7 years. The average follow-up period for all cases was 10 years. Conclusion: Patients with craniopharyngioma generally present late, and the visual symptoms are often preceded by a long history of systemic symptoms. Children are more likely to present with systemic symptoms than adults. Visual field pleomorphism is a feature of craniopharyngioma and occurred in one-third of the patients. Local recurrence is common. Although magnetic resonance imaging is the recommended means of follow up, regular neuro-ophthalmic review is useful in the early detection of anterior visual pathway compression by recurrent tumour. [source] Complete unilateral leg duplication with ipsilateral renal agenesisACTA PAEDIATRICA, Issue 3 2007Christian Lilje Abstract A case of a 5-month-old infant with complete duplication of the right leg and ipsilateral renal agenesis is presented. There was also a duplicated scrotum, posterior urethral valves with hydronephrosis, abnormal pelvic bones, and a ventricular septal defect. Complete caudal duplication is exceedingly rare. Associated defects are common. Several aetiological theories have been proposed. Among them, an underlying polytopic (acro-renal) developmental field defect has been suggested. It best explains the specific findings in our patient. However, the aetiology of caudal duplication syndromes may be multifactorial. In the light of twinning theories, associated duplication of hindgut derivates should be suspected in similar cases. Further research is needed. The motor-skeletal functional outcome after leg duplication surgery is mostly favourable. Conclusion: A case of complete unilateral leg duplication with ipsilateral renal agenesis is presented. It appears to support the theory of a polytopic developmental field defect. [source] Detection of glaucomatous damage using multifocal ERGCLINICAL AND EXPERIMENTAL OPTOMETRY, Issue 6 2005Henry Ho-Lung Chan PhD FAAO The first-order kernel analysis in multifocal electroretinogram (mfERG) using low contrast stimulation is suggested as a way to detect the inner retinal responses in animal studies. In this case report, this protocol is applied to human patients with glaucoma to demonstrate the possibility of using mfERG as a tool to detect glaucomatous damage. Two patients with glaucoma were recruited and had mfERG measurements with the 103-scaled hexagonal stimulus pattern at low (50 per cent) contrast. Their responses were analysed and compared with those from normal subjects with the mfERG measured under the same condition. In the normal subjects, there were obvious oscillatory components on the ascending and descending limbs of the first-order kernel response to 50 per cent contrast. In the glaucomatous patients, the oscillatory component on the descending limb was obviously diminished. In addition, this component was significantly diminished in the quadrant with a glaucomatous visual field defect. This suggests that the low-contrast stimulation condition in mERG measurement may provide a good way to detect glaucomatous damage and this may help in clinical diagnosis of glaucoma. [source] CASE REPORT: Clinical application of mfERG/VEP in assessing superior altitudinal hemifield lossCLINICAL AND EXPERIMENTAL OPTOMETRY, Issue 4 2005Dr Henry Ho-lung Chan PhD FAAO Multifocal ERG (mfERG) and multifocal VEP (mfVEP) have been used widely in the investigation of pathological changes or functional variations in the visual system. Altitudinal hemifield loss is a visual field defect that is usually found in patients with ischaemic optic neuropathy (ION). Anterior ischaemic optic neuropathy (AION) is a complex multi-factorial disease and it is difficult to diagnose according to clinical symptoms and signs alone. AION is believed to be caused by an infarction of the optic nerve due to the occlusion of the posterior ciliary arteries. The current report presents a patient diagnosed with non-arteritic AION. In this report, the mfERG findings did not match the results of the visual field test but those of the mfVEP did. After consideration of the visual electrophysiological and visual field results, the defect arises from neither the retina nor the visual pathway behind the optic chiasma. Hence, the optic nerve is the most likely location of the lesion, causing the superior altitudinal hemi-field loss. This report shows that the mfERG and mfVEP techniques can be used for objective visual field assessment to supplement the conventional visual field testing. [source] Plasticity of the visual system after early brain damageDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 10 2010ANDREA GUZZETTA The aim of this review is to discuss the existing evidence supporting different processes of visual brain plasticity after early damage, as opposed to damage that occurs during adulthood. There is initial evidence that some of the neuroplastic mechanisms adopted by the brain after early damage to the visual system are unavailable at a later stage. These are, for example, the ability to differentiate functional tissue within a larger dysplastic cortex during its formation, or to develop new thalamo-cortical connections able to bypass the lesion and reach their cortical destination in the occipital cortex. The young brain also uses the same mechanisms available at later stages of development but in a more efficient way. For example, in people with visual field defects of central origin, the anatomical expansion of the extrastriatal visual network is greater after an early lesion than after a later one, which results in more efficient mechanisms of visual exploration of the blind field. A similar mechanism is likely to support some of the differences found in people with blindsight, the phenomenon of unconscious visual perception in the blind field. In particular, compared with people with late lesions, those with early brain damage appear to have stronger subjective awareness of stimuli hitting the blind visual field, reported as a conscious feeling that something is present in the visual field. Expanding our knowledge of these mechanisms could help the development of early therapeutic interventions aimed at supporting and enhancing visual reorganization at a time of greatest potential brain plasticity. [source] Vigabatrin, but not Gabapentin or Topiramate, Produces Concentration-related Effects on Enzymes and Intermediates of the GABA Shunt in Rat Brain and RetinaEPILEPSIA, Issue 7 2003Graeme J. Sills Summary: Purpose: The antiepileptic drug (AED) vigabatrin (VGB), which exerts its pharmacologic effects on the ,-aminobutyric acid (GABA) system, causes concentric visual field constriction in >40% of exposed adults. This may be a class effect of all agents with GABA-related mechanisms of action. We compared the concentration-related effects of VGB in rat brain and eye with those of gabapentin (GBP) and topiramate (TPM), both of which have been reported to elevate brain GABA concentrations in humans. Methods: Adult male rats (n = 10) were administered 0.9% saline (control), VGB (250, 500, 1,000 mg/kg), GBP (50, 100, 200 mg/kg), or TPM (12.5, 25, 50, 100 mg/kg). At 2 h after dosing, animals were killed, a blood sample obtained, the brain dissected into eight distinct regions, and the retina and vitreous humor isolated from each eye. Samples were analyzed for several GABA-related neurochemical parameters, and serum and tissue drug concentrations determined. Results: VGB treatment produced a significant (p < 0.05) dose-related increase in GABA concentrations and decrease in GABA-transaminase activity in all tissues investigated. This effect was most pronounced in the retina, where VGB concentrations were 18.5-fold higher than those in brain. In contrast, GBP and TPM were without effect on any of the neurochemical parameters investigated and did not accumulate appreciably in the retina. Conclusions: These findings corroborate a previously reported accumulation of VGB in the retina, which may be responsible for the visual field constriction observed clinically. This phenomenon does not appear to extend to other GABAergic drugs, suggesting that these agents might not cause visual field defects. [source] The Role of Vigabatrin in Childhood Seizure Disorders: Results from a Clinical AuditEPILEPSIA, Issue 1 2001Asuri N. Prasad Summary: ,Purpose: The emergence of visual field defects attributed to vigabatrin (VGB) treatment and intramyelinic edema in animal experiments has raised concerns about its future role in the treatment of childhood seizures. Methods: We evaluated our experience with this antiepileptic agent with retrospective analysis of database and chart audit. Results: Of 73 patients, 43 girls and 33 boys were treated with VGB over a 7-year period. The mean age of patients at the introduction of VGB was 87 months (range, 5,257 months). In 12 of 73 cases, VGB was used as monotherapy; in 61 of 73 cases, it was used as an add-on drug. Seizure types included secondarily generalized seizures (21), mixed seizures (21), partial seizures (18), and generalized seizures (13). Seizure etiology was idiopathic/cryptogenic in 22 patients, symptomatic in 50, and undetermined in a single patient. The mean duration of therapy was 16 months (median, 10 months; range, 1,144 months). VGB was effective in 30 (seven seizure free, 23 with >90% reduction in seizures), partially effective in four (50,90% reduction in seizures), and ineffective in 38 (<50% reduction in seizures). Nearly 50% of patients with infantile spasms responded to VGB. All patients underwent ophthalmic evaluation; two (16%) of 12 patients who could undergo static threshold perimetry were demonstrated to have the characteristic visual field constriction. Conclusions: VGB is effective in producing a significant reduction in seizure frequency in nearly half the patients with childhood seizures, including refractory epilepsy. Despite emerging concerns regarding visual side effects, this drug retains an important role in the medical management of childhood epilepsy. [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] Chronic open angle glaucoma: patient awareness of the nature of the disease, topical medication, compliance and the prevalence of systemic symptomsOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 1 2004Sunil Deokule Abstract Purpose:, To study the awareness of the nature of the disease, compliance with treatment, and prevalence of systemic symptoms in a group of patients with chronic open angle glaucoma (COAG). Method:, A structured questionnaire was designed and given to 260 consecutive COAG patients attending a general ophthalmology clinic. Questions related to the increased risk of COAG amongst family members, screening of family members, nature of field defects, variation in IOP, topical treatment and availability of a free eye test for a COAG patient in the UK were asked. Compliance and systemic symptoms were also assessed. Results:, Forty-one per cent (107 of 260) of patients in the study group were aware of the increased risk of COAG in family members and 45.5% (118 of 260) of patient's family members had undergone screening for COAG. Seventy-three per cent (191 of 260) of the patients were aware of their own and their family members' entitlement to a free eye test. Seventy-seven per cent of patients claimed full compliance. Thirty per cent of patients were noted to have systemic symptoms. Conclusions:, The awareness of the nature of COAG in this population was low and incidence of perceived drug related systemic symptoms very high. Both of these may contribute to poor compliance. [source] The detection of small simulated field defects using multifocal VEPsOPHTHALMIC AND PHYSIOLOGICAL OPTICS, Issue 3 2003H. L. Chan Abstract Introduction: The multifocal visual-evoked potential (mfVEP) has been widely investigated in the study of diseases of the visual system. However, the sensitivity of the mfVEP in objective detection of field defects has not been determined. This study investigates the variation of the mfVEP responses whilst simulating field defects by using different sizes of mask on the stimulus pattern. Methods: Simulated field defects of four different sizes (2, 3, 5, and 7 degrees) at two different eccentricities (10 and 16 degrees) were generated on a standard mfVEP dartboard stimulus using opaque masks. These masks were placed at the centre of each dartboard sector and the modified stimuli were used to elicit mfVEPs from 10 normal subjects. The response densities and latencies of N1, P1 of the mfVEP were compared, without and with small simulated field defects. Results: The minimum size of simulated field defect causing significant response density reduction in P1 and N1 was 5 degrees at both retinal eccentricities. N1 showed similar reduction in response density at both retinal eccentricities, but P1 showed larger reduction at the 10-degree location than at the 16-degree location. There was no change in latencies with simulated field defect at either location. Conclusions: The mfVEP is only sensitive to a simulated field defect equal to or larger than 5 degrees in diameter, and mfVEP has greater sensitivity at 10-degree eccentricity than at 16-degree eccentricity. [source] A multicenter, prospective pilot study of gamma knife radiosurgery for mesial temporal lobe epilepsy: Seizure response, adverse events, and verbal memory,ANNALS OF NEUROLOGY, Issue 2 2009Nicholas M. Barbaro MD Objective The safety, efficacy, and morbidity of radiosurgery (RS) must be established before it can be offered as an alternative to open surgery for unilateral mesial temporal lobe epilepsy. We report the 3-year outcomes of a multicenter, prospective pilot study of RS. Methods RS was randomized to 20 or 24Gy targeting the amygdala, hippocampus, and parahippocampal gyrus. Seizure diaries evaluated the final seizure remission between months 24 and 36. Verbal memory was evaluated at baseline and 24m with the Wechsler Memory Scale,Revised (WMS-R) and California Verbal Learning Test (CVLT). Patients were classified as having "significant improvement," "no change," and "significant impairment" based on relative change indices. Results Thirteen high-dose and 17 low-dose patients were treated. Both groups showed significant reductions in seizures by 1 year after treatment. At the 36-month follow-up evaluation, 67% of patients were free of seizures for the prior 12 months (high dose: 10/13, 76.9%; low dose: 10/17, 58.8%). Use of steroids, headaches, and visual field defects did not differ by dose or seizure remission. The prevalence of verbal memory impairment was 15% (4/26 patients); none declined on more than one measure. The prevalence of significant verbal memory improvements was 12% (3/26). Interpretation RS for unilateral mesial temporal lobe epilepsy offers seizure remission rates comparable with those reported previously for open surgery. There were no major safety concerns with high-dose RS compared with low-dose RS. Additional research is required to determine whether RS may be a treatment option for some patients with mesial temporal lobe epilepsy. Ann Neurol 2009 [source] Anatomical and functional outcome in brilliant blue G assisted chromovitrectomyACTA OPHTHALMOLOGICA, Issue 5 2010Paul B. Henrich Abstract. Purpose:, To evaluate the potential of brilliant blue G (BBG) for intraoperative staining of the inner limiting membrane (ILM) with respect to staining properties and surgical outcome. Methods:, In a retrospective, non-comparative clinical case series, we analysed 17 consecutive chromovitrectomy interventions for surgery of macular holes, ERMs, vitreoretinal traction syndromes and cystoid macular oedema. Following complete posterior vitreous detachment, BBG was injected into the vitreous cavity at a concentration of 0.25 mg/ml, followed by immediate washout. Main outcome measures were staining properties, visual acuity, central visual field testing and optical coherence tomography (OCT) measurements over a mean follow-up period of 3 months. Results:, ILM staining was somewhat less intensive for BBG than for average indocyanine green (ICG) chromovitrectomy. However, the ILM was removed successfully without additional ICG in 15/17 patients. Postoperative visual acuity was improved in 16/17 patients and remained unchanged in one patient. Central retinal OCT thickness showed a postoperative reduction, with values ranging from +7 to ,295 ,m (median ,89 ,m). Neither visual field defects nor any other adverse events were recorded. Conclusion:, BBG permits sufficient staining for safe ILM removal. In this short-term study, good anatomical and functional results were achieved and no adverse events were observed. [source] Temporal visual field defects are associated with monocular inattention in chiasmal pathologyACTA OPHTHALMOLOGICA, Issue 7 2009Hans C. FledeliusArticle first published online: 24 OCT 200 Abstract. Purpose:, Chiasmal lesions have been shown to give rise occasionally to uni-ocular temporal inattention, which cannot be compensated for by volitional eye movement. This article describes the assessments of 46 such patients with chiasmal pathology. It aims to determine the clinical spectrum of this disorder, including interference with reading. Methods:, Retrospective consecutive observational clinical case study over a 7-year period comprising 46 patients with chiasmal field loss of varying degrees. Observation of reading behaviour during monocular visual acuity testing ascertained from consecutive patients who appeared unable to read optotypes on the temporal side of the chart. Visual fields were evaluated by kinetic (Goldmann) and static (Octopus) techniques. Five patients who clearly manifested this condition are presented in more detail. The results of visual field testing were related to absence or presence of uni-ocular visual inattentive behaviour for distance visual acuity testing and/or reading printed text. Results:, Despite normal eye movements, the 46 patients making up the clinical series perceived only optotypes in the nasal part of the chart, in one eye or in both, when tested for each eye in turn. The temporal optotypes were ignored, and this behaviour persisted despite instruction to search for any additional letters temporal to those, which had been seen. This phenomenon of unilateral visual inattention held for both eyes in 18 and was unilateral in the remaining 28 patients. Partial or full reversibility after treatment was recorded in 21 of the 39 for whom reliable follow-up data were available. Reading a text was affected in 24 individuals, and permanently so in six. Conclusion:, A neglect-like spatial unawareness and a lack of cognitive compensation for varying degrees of temporal visual field loss were present in all the patients observed. Not only is visual field loss a feature of chiasmal pathology, but the higher visual function of affording attention within the temporal visual field by means of using conscious thought to invoke appropriate compensatory eye movement was also absent. This suggests the possibility of ,trans-synaptic dysfunction' caused by loss of visual input to higher visual centres. When inattention to the temporal side is manifest on monocular visual testing it should raise the suspicion of chiasmal pathology. [source] Noninvasive oximetry and glaucomaACTA OPHTHALMOLOGICA, Issue 2009OB OLAFSDOTTIR Purpose To investigate retinal vessel oxygen saturation in relation to glaucomatous visual field damage. Specifically, we examined whether oxygen saturation in retinal blood vessels differs between regions corresponding to glaucomatous visual field defects compared to regions without visual field defects. Methods A spectrophotometric retinal oximeter (Oxymap ehf, Reykjavík, Iceland) was used to measure oxygen saturation in retinal arterioles and venules. The oximeter consists of a fundus camera, beam splitter, light filters and software that evaluate the oxygen saturation. The glaucomatous defect was estimated from a visual field test using the Octopus 1-2-3 perimeter. One eye in 13 individuals with open angle glaucoma with or without pseudoexfoliation syndrome was examined. Results In retinal areas with no visual field defect, the mean oxygen saturation in arterioles was 102±6% and 65±9%, (mean±SD) in venules. The arteriovenous difference was 37±10%. In retinal areas corresponding to visual field defects, the mean oxygen saturation in arterioles was significantly lower; 98±5% (p=0.04, paired t-test, n=13). The venules were at 68±7% (p=0.3) and the arteriovenous difference was also significantly lower; 30±10% (p=0.04). Conclusion Arteriolar oxygen saturation and arteriovenous difference is statistically lower in areas with visual field defects compared to areas without visual field defects. This data suggests that visual field defects are associated with a reduction in retinal oxygen delivery and metabolism. [source] Relationship between standard automated perimetry and high-resolution optical coherence tomography in glaucoma patientsACTA OPHTHALMOLOGICA, Issue 2009P CALVO PEREZ Purpose To determine the relationship between the main indices of standard automated perimetry (SAP) and the peripapillary retinal nerve fiber layer (RNFL) thickness measured with spectral-domain optical coherence tomography (OCT) in patients with glaucomatous visual field defects. Methods 47 consecutive patients with open-angle glaucoma were included in the study. Only one eye per subject was randomly selected. SAPs were performed with a Humphrey perimeter and the 24-2 SITA standard algorithm. All of them underwent imaging with the Spectralis OCT (Heidelberg Engineering, Heidelberg, Germany). Left eye data were converted to a right eye format. The Kolmogorov Smirnov test was applied to check that the data were normally distributed. Pearson correlations were calculated between SAP indices (mean deviation, pattern standard deviation, and visual field index) and OCT parameters Results The average visual field mean deviation was -6.50 dB. Mild to moderate correlations were observed between SAP indices and most OCT parameters. The strongest correlations were found between the inferior quadrant thickness and pattern standard deviation (-0.544). Conclusion The RNFL thicknesses measured with high-resolution OCT showed moderate correlations with SAP indices in glaucoma patients. These results may help to understand the relationship between structural and functional changes in open-angle glaucoma. [source] Toxic effect of vigabatrin on retinal nerve fiber layerACTA OPHTHALMOLOGICA, Issue 2009A MIDELFART Purpose To investigate whether peripheral and central visual field defects detected among epilepsy patients treated with vigabatrin are associated with reduced peripapillary retinal nerve fiber layer thickness as measured with optic coherence tomography (OCT). Methods Nine epilepsy patients with vigabatrin-attributed visual field loss (group 1) and seven patients(age and sex matched) with epilepsy treated with other drugs(control group 2) were regularly examined with automated perimetry up to 60 degrees from fixation point (Humphrey Field Analyser). Peripapillary retinal nerve fiber layer thickness (RNFLT) was quantified by optic coherence tomography (OCT) using Fast RNFLT protocol, Stratus OCT (3.0). Five of the patients in group 1 had peripheral visual field defects, (group 1a), four had a central field defect(group 1b). All patients in control group 2 had normal visual field. Results Patients with vigabatrin-attributed visual field loss had attenuated total RNFLT compared to controls (right eye : mean total RNFLT: group 1: 75.6 µm (SD 12.7); group 2: 103.5 µm (SD 9.7), mean difference 27.9 µm (CI 15.9-39.9;P < 0.001). The nasal and inferior sectors RNFLT were more attenuated in patients with vigabatrin-attributed visual field loss compared to controls, while no difference was detected in the temporal RNFLT. Both individuals with peripheral and central visual field losses had attenuated mean total RNFLT compared to controls (P = 0.006 and P= 0.002, respectively). Conclusion Vigabatrin-attributed visual field defects are associated with reduced RNFLT. Combination of perimetry and OCT can efficiently detect vigabatrin induced retinal nerve fiber damage. [source] The Beijing Eye StudyACTA OPHTHALMOLOGICA, Issue 3 2009Jost B. Jonas Abstract. Purpose:, This review presents and summarizes the findings of the Beijing Eye Study. Methods:, The Beijing Eye Study is a population-based study which included 4439 of 5324 subjects (aged , 40 years) who were initially examined in 2001. The study was repeated in 2006, when 3251 (73.2% of 4439, or 61.1% of 5324) of the original subjects participated. Participants underwent a series of examinations including: refractometry; pneumotonometry; biomicroscopy assisted by slit-lamp; optical coherence tomography of the anterior segment; photography of the cornea, lens, optic disc, macula and fundus; blood sampling for laboratory tests; blood pressure measurements, and determinations of anthropomorphic parameters. They were also asked to complete a questionnaire which included questions on socioeconomic parameters, and awareness and treatment of ocular and general diseases. Results:, We present normative data for refractive error, anterior segment measurements, intraocular pressure and optic disc structures and their associations, frequency and causes of visual impairment, blindness and visual field defects, prevalences of trachoma, pterygia, open-angle glaucoma and angle-closure glaucoma, cortical, nuclear and posterior subcapsular cataract, age-related macular degeneration, retinal vein occlusions, diabetes mellitus and diabetic retinopathy, myelinated nerve fibres, and retinitis pigmentosa, and associated and risk factors. Discussion:, These data may be helpful for dealing with public health issues in China and for assessing associated and risk factors of ocular and general diseases in general. [source] Prevalence of optic disc drusen in an adult Chinese population: the Beijing Eye StudyACTA OPHTHALMOLOGICA, Issue 2 2009Qi Sheng You Abstract. Purpose:, This study aimed to determine the prevalence of optic disc drusen and their associations with ocular and general parameters. Methods:, The Beijing Eye Study included 4439 of 5324 subjects invited to participate (response rate 83.4%). All subjects were aged , 40 years. The present investigation involved 8594 (96.8%) eyes of 4324 (97.4%) subjects from whom readable fundus photographs of at least one eye were available. The main outcome parameter was the presence of optic disc drusen defined as round, whitish bodies. Results:, Optic disc drusen were detected in nine (0.1 ± 0.05%) eyes of eight subjects (five women). The prevalence rate was 0.2 ± 0.07% (95% confidence interval 0.07,0.33%) per subject. Optic disc drusen were significantly associated with small optic discs (p < 0.001). They were not statistically associated with age (p = 0.90), gender (p = 0.73), intraocular pressure (p = 0.97), refractive error (p = 0.71), visual field defects (p = 0.47) or corrected visual acuity (p = 0.84). Conclusions:, Optic disc drusen are present in about two in 1000 adult Chinese people in Northern China. The main associated factor is a small optic disc. [source] Tilted disc syndrome may mimic false visual field deteriorationACTA OPHTHALMOLOGICA, Issue 6 2008Marja-Liisa Vuori Abstract. Purpose:, Tilted disc syndrome is a congenital anomaly of the eye characterized by mostly upper temporal visual field defects. The aim of the present study was to evaluate the effect of gradual myopic correction in the improvement of visual field defects associated with tilted disc syndrome. Methods:, The visual field was examined in 38 eyes of 24 patients using standard Goldmann perimetry. The isoptres IV-4e, I-4e, I-3e and I-2e were plotted. The defective isoptres were tested again with gradually increasing myopic correction until no further change was noted. Results:, The most common type of defect was a relative upper temporal defect (19 eyes). Temporal relative defects were found in five eyes, upper altitudinal field defects in six eyes, an enlarged blind spot in four eyes, and an inferior field defect in one eye. The visual field defect partly or totally disappeared with increased myopic correction in 18 (50%) eyes. The mean improvement was 17.0 ± 6.2 degrees and the mean additional myopic correction was 3.1 ± 1.5 D. Conclusions:, Even a small change in near correction during visual field examination may imply worsened or improved visual field defects in tilted disc syndrome. To prevent a false interpretation of field deterioration in a patient with tilted disc syndrome and glaucoma, visual field assessment should include examination with the myopic correction that provides the maximal improvement of the defective visual field. [source] Is AZOOR an autoimmune disease?ACTA OPHTHALMOLOGICA, Issue 2007SF SEIDOVA Purpose: Acute zonal occult outer retinopathy (AZOOR) is one of the "white dot syndromes" a clinically heterogeneous group of inflammatory chorioretinopathies. The etiology is not yet clear. Methods: We present a 50 years female patient with a prior history of migraine. She experienced progressive visual loss and visual field defects in the last 3 years. Preceding each episode she experienced blue flickering photopsias. Results: Visual acuity was 0,3 in the right eye and 0,6 in the left eye. Biomicroscopy showed a normal anterior segment, fundus exam revealed pigment epithelial atrophy more pronounced in the worse eye. Electrophysiology showed a marked reduction in the photopic ERG in the more affected eye. MRI demonstrated multiple white matter lesions including a corpus callosum location. Lumbar puncture showed oligoclonal bands. Further tests demonstrated hearing impairment. Therapy was instituted during the three years course of the disease with steroids, immune suppressants and plasmapheresis with visual loss being progressive. New photopsia is currently present. Conclusions: The etiology of AZOOR remains unclear. With our patient being one of the few described in the literature with concomitant multiple sclerosis, the question remains on whether there is an underlying common process of inflammatory autoimmune reactions. Whether treatment is possible, remains to be evaluated. [source] | ||||||||||