bluuebunny/crossref_metadata_2025_split huggingface dataset:
Neuromyelitis optica and AQP4 antibodies in consecutive optic neuritis patients
Authors: SIUKO M , TIENARI PJ , KIVELÄ T , SAASTAMOINEN KP , MIETTINEN A , SETÄLÄ K 
Published: November 2010

Abstract Purpose To analyse the frequency of neuromyelitis optica (NMO) among consecutive optic neuritis (ON) patients in Southern Finland and to analyse correlation of Aquaporin‐4 (AQP4) antibody titre with the severity of ON and with the diagnosis of NMO. Methods All patients with symptoms suggestive of acute ON and treated in the Helsinki Eye Hospital have been screened for AQP4 antibodies from May 2008 onwards. Diagnosis of NMO among the ON patients was evaluated prospectively and retrospectively. AQP4 antibodies were measured using Radioimmunoprecipitation assay (Seelig‐lab). Antibody titres >15 were considered pathological, 10‐15 borderline, and <10 were considered normal. Brain magnetic resonance imaging (MRI) was performed in all patients. Results We screened 131 patients who had symptoms suggesting ON. Of the 131 patients 24 (18%) were eventually diagnosed with a condition other than ON. Of the remaining 107 patients classified as ON (77% females), 35 (33%) had multiple sclerosis (MS), 25 (23%) had demyelination by MRI, but did not fulfill the criteria for MS, and 47 (44%) had no MRI evidence of demyelination. The median AQP4 anti‐body titer was 7.3 (range 4.8‐53.5). Pathological AQP4 antibody titres were found in three cases, one with NMO, one with MS and one with a clinically isolated syndrome suggestive of MS fulfilling Barkhof’s MRI criteria. Borderline AQP4 antibody titres were found in 8 cases. Only one patient with NMO was found and he had pathological AQP4 antibody titer. Conclusion In the southern Finnish population, NMO is rare among ON patients. In this cohort the AQP4 antibody test was not specific for NMO.
The effects of stress on nystagmus (INS): acuity vs. time to see
Authors: ERICHSEN JT , WOODHOUSE JM , MARGRAIN TH , ENNIS F , HARRIS CM , JONES PH 
Published: November 2010

Abstract Purpose People with congenital nystagmus (INS) report that stress has a deleterious impact their vision, yet recent research suggests that stress does not affect visual acuity (VA). This study investigated what underlies the perception that stress causes poorer vision in INS. Methods VA was measured using a two alternate forced choice (2AFC) staircase method. Subjects were asked to identify whether the gap in a Landolt C of decreasing size was either left or right. Eye movements and skin conductance (a measure of arousal level) were simultaneously recorded. Stress was induced with the threat of a brief shock from a Transcutaneous Electric Nerve Stimulation (TENS) machine at double the subject’s previously determined threshold, although this was never actually done. Subjects carried out the visual task four time: twice under relaxed conditions, and twice under stressed conditions (i.e. shock linked to performance and shock at random intervals). Results The intensity of eye movements was significantly increased during periods of stress (paired t test, p<0.05), as was skin conductance (p<0.05). Consistent with other studies, VA was not affected (p=0.73), but the time taken for subjects to respond to the stimulus was significantly longer during periods of stress (p<0.05). Conclusion The results suggest that aspects of “vision” other than VA can better reflect the problems experienced by people with INS when under stress. We confirm that VA is unaffected; subjects do take longer to identify the target. We conclude that clinical or experimental measures of VA alone are insufficient to determine the visual problems faced by people with nystagmus. Additional tests such as measurement of the time taken to identify a target are recommended.
Laser and oxygen
Authors: POURNARAS CJ 
Published: November 2010

Abstract Purpose To evaluate the changes in the retinal oxygen partial pressure (PO2) following photocoagulation as well as the resulting effect of the laser induced improved oxygenation, on the retinal vessels hemodynamics. Methods Measurements of the partial pressure of oxygen (PO2) distribution within the retina in various animal species using oxygen sensitive microelectrodes and evaluation of changes on the retinal vessels reactivity, following laser treatment, gave additional insights concerning photocoagulation mechanisms. Results Preretinal intervascular PO2 , far away from vessels, remain constant in all retinal areas. Intervascular intraretinal PO2 gradually decreases from both the vitreo‐retinal interface and the choroid towards the mid‐retina. Close to the pigment epithelium, it is significantly higher than at the vitreoretinal interface due to the much higher O2 supply provided by choroidal compaires to retinal circulation. Laser photocoagulation reduces the outer retina O2 consumption and allows O2 diffusion into the inner retina from the choroid raising the PO2 in the inner healthy retinal layers and in the preretinal intervascular normal areas. In this way, laser treatment relieves retinal hypoxia in experimental branch vein occlusion (BRVO). In patients with diabetic retinopathy (DR), the retinal PO2 is also higher in areas previously treated with laser. Following photocoagulation, the resulting reversal of hypoxia, the down‐regulation of the VEGF expression, the retinal vasculature constriction and the improvement of the auto‐regulatory response to physiological stimuli, all affect favorably both the retinal neovascularisation and macular edema. Conclusion Photocoagulation induces an increase of the inner retinal oxygenation resulting to an improvement of the autoregulatory retinal vessels response.
Mesopic visual function as a prognostic indicator of early age‐related maculopathy
Authors: PEREZ CARRASCO MJ , PUELL MC , BARRIO AR , PALOMO‐ALVAREZ C , GOMEZ‐SANZ FJ , CLEMENT‐CORRAL A 
Published: November 2010

Abstract Purpose Rod photoreceptors, which mediate night vision, are vulnerable early in age‐related maculopathy (ARM) pathogenesis. This study was performed to analyze mesopic visual function of early ARM subjects. Methods The samples were 40 early ARM eyes of adults (65 ± 7 years), and 34 age‐matched healthy control eyes (67 ± 6 years). The selected criteria in both samples were: Best‐corrected VA of at least 0.9 decimal. Under photopic (80 cd/m2) and mesopic (0.1 to 0.2 cd/m2) luminance conditions and with the best‐optical correction, the logMAR VA was measured using high‐contrast (HC‐96%) and low‐contrast (LC‐10%) logMAR Bailey‐Lovie letter charts, and the mesopic contrast sensitivity (CS) was assessed with Pelli‐Robson Test Results Photopic high and low‐contrast VA showed no statistically differences between the two groups. Under mesopic conditions, the HC logMAR VA was 0.54 ± 0.13 in ARM group and 0.46 ± 0.10 in Control group. The ARM LC logMAR VA was 0.72 ± 0.11 and the Control LC logMAR VA was 0.99 ± 0.13. Differences in mesopic high and low contrast logMAR VA between the Control and ARM group were statistically significant; the Control group showing best logMAR VA at high and low contrast (p< 0.00). The mesopic ARM logCS was 0.99 ± 0.21 and the mesopic Control logCS was 1.19 ± 0.14. In ARM group, the mean mesopic log CS was 0.2 ± 0.08 log units lower (p< 0.00) than in the Control group. Conclusion The results indicated that assessment of the mesopic high and low contrast logMAR VA and log CS might potentially predict the mesopic visual function and the first night‐vision problems of the early ARM disease process
Compartment syndrome in glaucoma damage, a new hypothesis?
Authors: ORGUL S 
Published: November 2010

Abstract Purpose To evaluate the potential similarities in pathophysiology between non‐arteritic anterior ischemic optic neuropathy (AION) and primary open‐angle glaucoma (POAG). Methods The currently accepted views of the pathophysiology of AION and general understanding of the clinical picture of this ischemic condition were reviewed. Based on the hypothesis of the group in Wisconsin, who postulated a compartment syndrome of the anterior optic nerve within the tight anatomical structures of the lamina cribrosa, parallels were drawn for glaucomatous optic neuropathy, and a new hypothesis for the pathogenesis of the latter condition was suggested. Results The tight structures around, but also within the “disk at risk” observed in a majority of patients with AION are well compatible with the hypothesis of a compartment syndrome. Similar conditions may result from the restructuring process within the lamina cribrosa in POAG and lead to locally limited, but repeated "AION‐like" processes, explaining why some patients progress despite reduced intraocular pressure. Conclusion The pathophysiology of POAG, especially in advanced cases, and AION seem to present similarities, which need to be better understood.
Pulsatile haemodynamics: potential for end‐organ damage?
Authors: HUDSON C 
Published: November 2010

Abstract Purpose Increases in velocity pulse wave amplitude, or max:min velocity ratio, represent early haemodynamic disturbances associated with diabetic retinopathy (DR) and age‐related macular degeneration. This change reflects an increase in vessel wall rigidity that is generally accepted to occur in the central vasculature but the peripheral vasculature is also implicated in this process. This presentation will highlight the implications of these changes in terms of end‐organ damage in DR. Methods The sample comprised 4 groups: Group 1: 50 non‐diabetic control subjects. Group 2: 56 diabetic patients without clinically visible DR. Group 3: 54 diabetic patients with micro‐aneurysms and / or hard exudates within 2 disc diameters of the fovea in the absence of clinically manifest diabetic macular edema (DME). Group 4: 40 patients with clinically manifest DME. The diabetic patients were predominantly type 2. Retinal hemodynamics were assessed in the superior temporal retinal arteriole using the Canon Laser Blood Flowmeter. Intraocular pressure, blood pressure and relevant systemic markers of diabetes control and complications were also assessed. Results The velocity pulse wave amplitude was elevated with increasing risk of DME (p<0.0001). No significant differences were found between the groups with respect to diameter, velocity or flow. Pulse wave amplitude was correlated to age, duration of diabetes, blood pressure, pulse rate, IOP and serum potassium levels. Conclusion The increase in velocity pulse wave amplitude will induce excessive pressure pulsatility in the retinal arterioles and capillaries, changes in vascular function (e.g. loss of vascular regulation) and changes in vessel structure.
Commercial interest
Alterations of the lid wiper zone in ocular surface disease
Authors: NEPP J 
Published: November 2010

Abstract Purpose The marginal part of the tarsal conjunctiva forms a lid wiper structure that wipes the ocular surface and distributes the tear film during the blink. It was attempted to investigate whether this region of the upper and lower lid shows specific changes in several kinds of ocular surface diseases. Methods 44 eyes of patients from the outdoor department of the university eye clinic Vienna were observed by slit lamp investigation of the ocular surface, vital staining with fluorescein and lissamin green. It was focused on evaluation of the tarsal conjunctiva including the lid margin and the wiper. Vessel dilatation, teleangiectatic changes and vital staining were each designed in three stages. The patients suffered from inflammation or affections of the lid, the conjunctiva and the cornea including chemical burns, graft versus host disease and injuries Results Compared to normal eyes dilatation of vessels and staining was observed more in patents with inflammations but although in serious affections like chemical burn or injuries. Even in corneal affections changes of vessels were observed. Conclusion Changes of the wiper can be observed in several diseases of the ocular surface and may be a sign of strain in this region.
A critical look at meibometry as a means to monitor Meibomian gland function
Authors: VERSURA P , PROFAZIO V , CAMPOS EC 
Published: November 2010

Abstract Purpose To evaluate the diagnostic performance of meibometry in classifying and quantifying Meibomian gland dysfunction(MGD) Methods Ninety‐six patients with MGD (138 eyes, 62 women, 34 men) and 30 normal control subjects(55 eyes)were enrolled. Eighty six eyes were classified as high delivery (HD)‐MGD (meibomian seborrhea/hypersecretory MGD), 52 as low delivery (LD)‐MGD on the basis of expression quality scores and morphological signs. Direct Meibometry (DM) measurements were made with an MB550 Meibometer (Courage‐Khazaka GmbH). Standard curves were constructed relating arbitrary Meibometer optical density units (AU). Integrated Meibometry (IM) was performed on scanned images of the lipid blots. Symptoms were scored by OSDI,Schirmer test I, Break Up Time (BUT), tear osmolarity (Tearlab, Ocusense), conjunctival scraping cytology were performed. Statistical analysis used SPSS 14.0 and MedCalc 5.0 Results AU values plotted on a log scale correlated highly with the lipid equivalent values (R2= 0.913). Significant differences were found between control subjects vs all MGD patients and between HD vs LD‐MGD patients for all the parameters evaluated. In particular: controls: 300+/‐121 AU (0.04+/‐0.015 microliter), LD‐MGD: 218+/‐122 AU (0.03+/‐0.015) and HD‐MGD: 564+/‐115 AU (0.07+0.015) (median+/‐SD). Significant correlation was found DM vs IM (r=0.691,p<0.0001) and DM was shown to be correlated with BUT, OSDI score, scraping score and tear osmolarity, especially in LD‐MGD patients. The selected DM diagnostic cut off for LD‐MGD was <275 AU (sens 73, spec 60, PPV 63) and for HD‐MGD was >450 AU; (sens 86, spec 87, PPV 91) Conclusion Meibometry is confirmed to be a reliable method to distinguish normal subjects from MGD subgroups with a good degree of accuracy
Can cytology differentiate Norrie's disease from Retinoblastoma?
Authors: TODOROVA M , BUBENDORF L , PRüNTE CH , FLAMMER J , MEYER P 
Published: November 2010

Abstract Purpose Objective: To describe the cytology characteristics in a case of Norrie’s disease. Methods This is a retrospective case report of a 3‐weeks‐old boy. Diagnosis was based on findings at the initial and follow‐up examinations, cytology of the pseudotumor mass and the retina of both eyes and genetic work up. Results The excised material was rich of cells with dense structures of small, round and blue nuclei. The cells stained positive for synaptophysin and displayed a proliferation rate of less than 5%. DNA sequence analysis revealed a heterozygosity of the mother and a hemizygosity of the child for the Norrie's disease associated NDP gene c.1A>G (p.M1V) sequence variant. Conclusion The small proportion of proliferating cells as well as the synoptophysin positive phenotype of the retina point towards dysplastic retina and argue against retinoblastoma. Taken the cytological results together with the genetic analysis into account a X‐linked Norrie’s disease could be confirmed. Thus, cytology complemented by immunocytochemistry seems to be a useful tool to promptly differentiate patients with Norrie’s syndrome from those with retinoblastoma.
OCT evaluation of progression in dry forms of age‐related macular degeneration
Authors: CORTES MORA N , PASTOR IDOATE S , LOPEZ MI 
Published: November 2010

Abstract Purpose To determine if OCT measure of the central mean macular thickness (CMMT) is a usefull parameter in the assesment of progression in dry forms of age related macular degeneration (d‐AMD) Methods Retrospective, comparative cohort study. Patients with initial diagnosis of Age Related Maculopathy (ARM) and follow up of at least 2 years were included. Exclussion criteria were stablished geographic atrophy and wet forms of AMD. Clinical recordings were reviewed to collect data about age, sex, tabaco and alcohol habit, HTA, DM, ETDRS visual acuity, atrophy area measured by autofluorescence and follow up. CMMT was assesed through SDOCT, that calculates the mean thickness of a central disc of 1,5mm, in order to obtain an objetive messure of the retinal atrophy. CMMT and the signal noise index (SNI) of the OCT were calculated at the begining and at the end of the follow up. Univariate analisys was performed to detect relationship between clinical variables and CMMT. Results 14 patients and 17 eyes with diagnosis of ARM were included. Mean Follow up was 20 months (SD=6). CMMT decreased from 235um to 210um in the follow up (p=0,043). There was a linear correlation between the CMMT and atrophy area measured by autofluorescence (R=0,621, p=0,031) and between CMMT and visual acuity (R=‐0,62, p=0,008). There wasn’t a diference in the SNI during the follow up. There weren’t relations between the other studied clinical variables and the CMMT. Conclusion Central mean macular thickness is an objetive, easy and usefull parameter in order to asses the progression of dry AMD.
Patients in the DARC: drops revealing retinal ganglion cells in vivo
Authors: CORDEIRO MF 
Published: November 2010

Abstract Purpose To provide a review of current & future DARC imaging technologies and their application to neuroprotection Methods Currently, lowering IOP remains the only clinical therapy available in the treatment of glaucoma, despite the evidence that vision loss can continue in the presence of “significant” IOP reduction. Neuroprotection has been increasingly recognized as an important alternative treatment approach, but its emergence has also highlighted the need for both better defined end‐points in clinical glaucoma research, as well as earlier and better detection and measures of progression. This could have been a factor in the recent memantine trial. A recent FDA/NEI meeting on end‐points in glaucoma emphasized the need for new measurements. As the RGC is the primary injured neuron in this disease, it would seem logical that any modality that could directly measure RGC dysfunction and disease would be ideal. Perhaps the greatest changes that we have encountered recently are in the field of imaging technologies, which have only relatively recently been applied to the eye. Results Advances in this area have allowed unprecedented in vivo access to the retinal layers, using many different properties of light to differentiate cellular structures. DARC is a technology shortly to enter clinical trials which allows the visualization of “sick” RGCs. Conclusion Over the next few years, developments in therapy & diagnostic using DARC should offer great potential in glaucoma and other neurodegenerative conditions.
Commercial interest
Optic disc in the picture: novel imaging techniques
Authors: DREXLER W 
Published: November 2010

Abstract Purpose Advances in light sources and detection technologies enabled a paradigm shift in retinal OCT imaging performance. ‘Snap‐shot OCT’ enabling isotropic sampling over 512x512x1024 voxels with 600 frames/second in less than a second is now possible. Methods The resolution advantage in conjunction with full volumetric sampling has enabled the development of more informative indices of axonal damage in glaucoma compared with measurements of RNFL thickness and cup to disc ratio provided by other devices. A novel mapping method was developed, the three‐dimensional minimal distance (3D‐MDM) as the optical correlate of true retinal nerve fiber layer thickness around the optic nerve head region. In a preliminary study relation between the cross‐sectional areas of the retinal nerve fiber layer and the optic nerve was found to be a sensitive measure of axon loss. Results In addition to all the major layers of the retina, the entire choroid down to the lamina cribrosa and sclera can now be visualized. This enables unprecedented information about choroidal vasculature without any contrast agents, choroidal thickness and will enable quantification of choroidal blood flow in the near future. Furthermore this technique allows tissue to be imaged in vitro with an image resolution better than 1‐2 µm, allowing to image single cells and detect pre‐apoptotic signatures using OCT. RGC‐5 cells were imaged using a sampling rate 1024x512x1024 voxel at 800 nm central wavelength and a bandwidth of 230 nm, enabling the detection of optical signatures at different pre‐stages of programmed cell death. Conclusion Significantly increased OCT imaging speed and tissue penetration might enable novel insights and diagnostic opportunities in the diagnosis and therapy monitoring of glaucoma.
Commercial interest
Distribution of light on the retina over extended periods
Authors: BONE R , GIBERT J 
Published: November 2010

Abstract Purpose Implicated in the etiology of age‐related macular degeneration (AMD) is photooxidative damage. Our purpose was to measure light distribution on the retina integrated over extended periods. Our hypothesis was that such distributions would peak in the macula where AMD is most evident. Methods Using an eye‐tracker, the subject's field of view, gaze position and pupil size were continuously recorded. 5 subjects familiar with the study formed a control group; 10 naïve subjects formed a test group. In phase 1, subjects viewed photographic images projected on a screen. In phase 2, they were seated before a monitor and asked to perform typical computer tasks. In phase 3, they moved freely around the lab. The control group was asked to gaze at bright objects in the field of view and, in a second test, at dark objects. The test subjects were allowed to gaze freely. Based on the subject’s gaze position and pupil size over 5 to 15 min periods, the cumulative light distribution on the retina was calculated Results For the control group, retinal illuminance peaked or dipped in the fovea for the tests in which subjects gazed at bright or dark objects respectively, thereby validating the experimental procedure. The retinal illuminace obtained from the test group in phase 2, but not in phase 1, consistently peaked at the fovea. In phase 3, such peaking occurred in 2 subjects. Conclusion Our data indicate that there may be specific tasks (e.g. computer usage) that expose the macula to increased illuminance compared with the surrounding retina, and that there may be some individuals for whom this is true under general viewing conditions. In these cases, higher illuminance in the macular region could result in increased photooxidative damage with implications for development of AMD.