bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ocular microbiota and polymorphonuclear leucocyte recruitment during overnight contact lens wear
Authors: Stapleton F , Willcox MDP , Sansey N , Holden BA 
Published: November 2007

ABSTRACTBacterial colonization of the ocular surface and contact lens (CL) and recruitment of polymorphonuclear leucocytes (PMN) during overnight CL wear was examined in I I asymptomatic wearers. The ocular surface was more frequently colonized than the CL with commensal bacteria (W0.05). Following sleep, more bacteria were recovered from the CL compared with daily use (P<0.05), and fewer PMN were recruited compared t o sleep without CL wear (Plt;0.05). Overnight CL wear may inhibit physiological PMN recruitment t o the cornea by preventing their access, by modifying the chemotactic signal o r by altering the activation state ofthe recruited cells.
Localization of D, dopamine receptors in the chicken retina
Authors: Firth SI , Morgan IG , Boelen MK 
Published: November 2007

ABSTRACTPurpose:The localization of dopamine D| receptors (DIR) in the chicken retina was examined using an anti‐human DI R. monoclonal antibody and PAP techniques.Results:A clear band of staining was seen in the outer plex‐iform layer; as well as cellular staining in the outer‐most part of the inner nuclear layer probably in a subset of horizontal cells. Many different amacrine cell bodies were labelled in the inner one‐third of the inner nuclear layer. There was also extensive staining in the inner plexiform layer; which showed some striation. Occasional labelled ganglion cells were also detected.Conclusion:Localization of DI‐dopamine receptors has
A fundamental step‐transition in retinal function at low light intensities
Authors: Morgan IG , Boelen MK 
Published: November 2007

ABSTRACTThere appears to be a fundamental step‐transition in retinal function at low light intensities, close to the scotopic‐mesopic transition. This step‐transition is observed for elements of the retinal dark‐light switch, which has been described in the chicken retina. Over the same range of light intensities, there is a step‐transition in photoreceptor retinomotor movements and in the coupling of horizontal and All amacrine cells, which suggests a switch in retinal circuitry from rod‐processing to cone‐processing regimes. A similar step‐transition in pineal function suggests that the retinal step‐transition signals to the central circadian systems. Finally, this step‐transition may also inhibit eye growth, and thus be responsible for the reported diurnal rhythm in eye growth. Disturbances to this step‐transition may be the initial cause of disordered eye growth in the form‐deprivation myopia paradigm.
Retinal control of scleral precursor synthesis
Authors: Devadas M , Morgan I 
Published: November 2007

ABSTRACTThere is a light‐dependent diurnal rhythm in scleral precursor synthesis (SPS). In form‐deprivation myopia (FDM) there is an increase in SPS. Daily periods of normal vision prevent FDM, but light intensities that maintain the retinal dark‐light switch in its dark state do not, implicating melatonin, dopamine, enkephalin, neurotensin and somatostatin in the control of SPS. FDM is also prevented by pirenzepine, a cholinergic muscarinic antagonist. To test if these compounds control the rate of SPS, agonists and antagonists were applied directly to the sclera, but the only effects detected were at very high concentrations, making them physiologically insignificant.
Correlations between observability of the spatial frequency doubled illusion and a multi‐region pattern electroretinogram
Authors: Bedford S , Maddess T , Rose KA , James AC 
Published: November 2007

ABSTRACTA glaucoma screening device based on the visibility of the spatial frequency doubled (FD) illusion will be marketed by Welch Allyn Ltd in the next year (ANU Patents (Australia) 611 585, (USA) 5 065 767 and application PL 3130). An underlying assumption of the method is that retinal processes are being tested. To test this assumption we compared the visibility of the FD illusion over a range of conditions and in the same spatial locations as a multi‐region pattern electroretinogram (PERG). Grating speed and contrast were good predictors of the psychometric functions and PERG amplitude and phase.
Relationship between cup‐disc ratio and optic disc diameter: The Blue Mountains Eye Study
Authors: Healey PR , Mitchell P , Smith W , Wang JJ 
Published: November 2007

ABSTRACTPurpose:To determine the effects of optic disc size on vertical cup‐disc ratio in subjects free of glaucoma and other optic nerve disease.Methods:Data were collected from 3654 people, 49 years of age or older; living in the Blue Mountains, west of Sydney (NSW, Australia). Examinations performed included subjective refraction and Zeiss colour stereo optic disc photographs. Eye and camera magnification effects were corrected.Results:Mean vertical disc diameter was 1.51 mm (95% confidence interval (CI) 1.504‐1.516 mm) and the mean vertical cup‐disc ratio was 0.43 (95% CI 0.425‐0.435). Both parameters were distributed unimodally. The cup‐disc ratio was strongly associated with disc diameter Controlling for other variables, cup‐disc ratio increased 0.270 (95% CI 0.250‐0.290) per mm increase in disc diameterConclusions:Vertical optic disc diameter and cup‐disc ratio are distributed near normally in older Australians. Optic discs with larger vertical diameters have considerably greater vertical cup‐disc ratios.
Lymphatic sinusoids exist in chick but not in rabbit choroid
Authors: Junghans BM , Crewther SG , Crewther DP , Pirie B 
Published: November 2007

ABSTRACTPurpose:Although it is generally thought that lymphatics do not exist in the choroid, there is mounting evidence that lymphatic‐like structures do exist in primates and fowl.Methods/Results:Our comparison of the ultrastructure of chick and rabbit outer choroid indicates that major differences exist in the non‐vascular areas of the choroid: notably, the chick has large lymphatic sinusoids, whereas the rabbit only has a system of large vacuoles contained within the processes of individual fibroblasts.Conclusions:These results raise questions regarding the similarities or otherwise between species of the management of retinal metabolites, excess tissue fluid and choroidal homeostasis, especially during conditions of overload.
An in‐service investigation of the additive effect of topical adrenergic agonists and beta‐blockers
Authors: Gillies WE , Brooks AMV 
Published: November 2007

Abstract Background: We assessed the long‐term additive effect of topical adrenaline or adrenaline precursor and betablockers because of doubts as to the presence and persistence of such an effect. Methods: In 43 patients (20 males and 23 females; mean (± SD) age 68.4 ± 11.5 years, range 24–84 years) on combined therapy for a mean 4.6 ± 4.4 years (range 3 months to 17 years) for chronic open‐angle glaucoma, the adrenaline or adrenaline precursor drop was stopped for 4 weeks in both eyes of 27 patients and in one eye of 16 patients. Results: There was a mean rise in intra‐ocular pressure (IOP) for the whole group from 17.5 ± 4.0 to 18.7 ± 4.9 mmHg (range 10–28 and 9–31 mmHg, respectively) on stopping adrenergic agonist drops. Three different responses were identified: (i) a rise in IOP < 2 mmHg (mean 5.8 ± 3.2 mmHg; range 3–14 mmHg) in 20 eyes of 15 patients; (ii) no rise or fall <2 mmHg in 43 eyes of 23 patients, with a mean rise of 0.2 ± 1.1 mmHg; and (iii) a fall in IOP of < 2 mmHg (mean 5.6 ± 3.2 mmHg; range 3‐1 1 mmHg) in seven eyes of five patients. Conclusions: The effect of adrenergic agonist and betablocker drops is variable, but an additive effect may be strong and persistent in some eyes, suggesting considerable variation in the distribution and density of adrenoceptors in different eyes. Therefore, there may be some variation in the effect of new α2‐adrenoceptor agonists, but such effects should be additive to those of beta‐blockers.
Acanthamoeba keratitis in New Zealand, including two cases with in vivo resistance to polyhexamethylene biguanide
Authors: Murdoch David , Gray Trevor B , Cursons Ray , Parr Dinah 
Published: November 2007

Abstract Background: Acanthamoeba keratitis is an uncommon corneal infection that can run a protracted course with, at times, serious visual results. Eighty‐five per cent of cases occur in soft contact lens wearers. The first New Zealand case occurred in 1990 and only seven cases have been identified in New Zealand to the end of 1996. Methods: We surveyed the ophthalmologists looking after these seven cases of acanthamoeba keratitis as to time to diagnosis, treatment and outcome. Results: New Zealand has a low incidence of this disease. All cases were soft contact lens wearers with defective care in every instance. After an initial two late‐diagnosed cases, the time to diagnosis for four of the five other cases has been within 2 weeks. Medical treatment has varied over this series, but since the introduction of the cationic antiseptics polyhexamethylene biguanide (PHMB) and chlorhexidine in 1992, the last five cases were all treated with PHMB. One case diagnosed within 2 weeks ran a devastating course, despite intensive PHMB, and a second case remained culture positive after I year of PHMB and the late addition of chlorhexidine. Debridement, 0. 1% PHMB and hexamidine eventually settled this eye. Conclusions: For treatment PHMB, hexamidine rather than propamidine and surgical debridement are favoured. While all Acanthamoeba isolates show good in vitro sensitivity to PHMB, the in vivo response is not always proportionate. A bacterial endosymbiont may have been a factor in the favourable outcome of one protracted case.
Trabeculectomy survival with and without intra‐operative 5‐fluorouracil application in an Asian population
Authors: Wong Jun Shyan , Yip Leonard , Tan Clement , Chew Paul 
Published: November 2007

Abstract Purpose: To define and compare the trabeculectomy survival with regard to intra‐ocular pressure (IOP) control without further surgery or anti‐glaucoma medication in an Asian population. Methods: A retrospective review of two consecutive groups of patients who had trabeculectomy surgery in a university eye department setting. The first group of patients (group A) did not receive any adjunctive 5‐fluorouracil (5‐FU), while the second group (group B) had intra‐operative sponge application of 5‐FU. Only the first trabeculectomy of patients who had bilateral trabeculectomy and the first trabeculectomy performed in patients who had repeated surgery was analysed. Combined procedures were excluded. Survival analysis was performed using the Kaplan‐Meier product limit method. Results: Eighty‐nine patients (51 in group A and 38 in group B) were studied, with a mean follow up of 37.5 and 27.0 months, respectively (P= 0.014). There were no statistical differences in age, gender, mean pretreatment IOP, pre‐operative medication, proportion of patients with previous ocular surgery, or proportion of primary compared with secondary glaucoma between the two groups. The probability of trabeculectomy survival (IOP < 22 mmHg without additional medication/surgery) at 12 and 36 months was 54.3 and 36.4%, respectively, in group A and 75.8 and 65.8%, respectively, in group B. The differences in survival were significant (P= 0.006, log rank test). Conclusions: Our experience with trabeculectomy survival in the Asian population showed poorer success when compared with Caucasian populations reported by other investigators. The survival of trabeculectomy surgery was improved significantly with intra‐operative 5‐FU. There may be justification for advocating a more liberal use of intra‐operative 5‐FU in such a population.
Post‐penetrating keratoplasty glaucoma: Risk factors, management and visual outcome
Authors: Sihota Ramanjit , Sharma Namrata , Panda Anita , Aggarwal Harish C , Singh Rajvir 
Published: November 2007

Abstract Purpose: To evaluate the incidence, associated risk factors, graft status and treatment modalities in patients with post‐penetrating keratoplasty glaucoma. Methods: A retrospective analysis of 747 consecutive penetrating keratoplasties was undertaken at a tertiary eye care centre. The frequency of post‐penetrating keratoplasty glaucoma was determined and correlated with the pre‐operative corneal diagnosis, lens status and associated surgeries performed during penetrating keratoplasty. The response to antiglaucoma therapy (i. e. medical, surgical or cyclo‐destructive procedures) and graft outcome was also evaluated. Results: The incidence of post‐penetrating keratoplasty glaucoma was 10.6% (79/747). Pre‐operative corneal diagnosis of adherent leucomas was significantly associated with the development of postoperative glaucoma. Post‐penetrating keratoplasty glaucoma was significantly higher in aphakes (odds ratio (OR) 6.6; confidence interval (CI) 3.81–11.69) compared with phakic or pseudophakic eyes. Associated vitrectomy (OR 2.32; CI 1.16–4.73) and anterior segment reconstruction (OR 3.31; CI 1.43–7.72) were other high‐risk factors. Most patients responded to medical therapy (41/79; 51.9%), whereas filtering surgery and cyclodestructive procedures were performed in 29.1 (23/79) and 19% (15/79) of eyes, respectively. Despite clear grafts in 39 eyes (49.4%), visual acuity of 6/18 or better was achieved in 15 eyes (18.9%). Conclusions: A high incidence of post‐penetrating keratoplasty glaucoma occurs in eyes with adherent leucomas. Anterior vitrectomy and associated surgeries further accentuate the risk. Anti‐glaucoma threrapy may not achieve optimum visual outcome, despite a clear graft.
Optic disc swelling in Crohn's disease
Authors: Walker JC , Selva D , Pietris G , Crompton JL 
Published: November 2007

Abstract Purpose: To provide a review of the causes of optic disc swelling in patients suffering from inflammatory bowel disease. Methods: Two illustrative cases of bilateral optic disc swelling are presented: one in a patient known to have Crohn's disease and the other in a patient whose investigations revealed the disease. The possible causes of optic disc swelling in inflammatory bowel disease, based on a literature review, are tabulated and discussed with reference to the presented cases. Results/Conclusions: Optic disc swelling is a rare complication of inflammatory bowel disease. Previously reported cases have been attributed to peripapillary inflammation, optic disc ischaemia or intracranial hypertension. Postulated causes of optic nerve ischaemia include a local vasculitis or general hypercoagulability. The underlying aetiology of intracranial hypertension is often elusive. Older studies suggest a relationship between corticosteroid treatment and/or iron deficiency anaemia, while modern imaging emphasises the need to exclude dural venous sinus thrombosis.
Effects of peripheral flicker masking on M‐ and P‐pathway response
Authors: Reynolds CH , Crewther DP , Crewther SG , BSc(Hons) SJ West 
Published: November 2007

Abstract Purpose: The effects of metahue and metacontrast masking on the responses of the M‐ and P‐pathways of the human visual system were investigated using temporal analysis of the multifocal flash visually evoked potential (VEP) (VERIS system). Methods: The experiments were carried out at three achromatic luminance contrasts, 24,70 and 96%, with three peripheral masks: a steady 65% grey mask, a grey flicker mask and an isoluminant red/green flicker mask. The stimuli were viewed monocularly and the mask and VERIS stimuli superposed with a mirror‐aperture system. Results/Conclusions: The masks had no significant effect on the behaviour of the M‐pathway as stimulus contrast increased. The amplitude of the P‐pathway was found to be approximately level at all contrasts of the stimulus and with all three masks rather than showing the expected steady increase in activity with increasing stimulus contrast.
Effect of lens opacity on the glaucomatous field of vision
Authors: Gillies WE , Brooks AMV 
Published: November 2007

Abstract Purpose: To assess the effect of cataract on the glaucomatous visual field. Methods: We prospectively assessed the visual field indices of mean deviation (MD), pattern standard deviation (PSD), short‐term fluctuation (SF) and corrected pattern standard deviation (CPSD) before and after cataract extraction with posterior chamber intra‐ocular lens in a consecutive series of 40 patients (51 eyes) age 75.0 ± 6.0 years with varying degrees of field loss or suspect field loss. Results: After cataract operation, statistical analysis showed a very significant fall in the absolute magnitude of MD and a significant rise in PSD. There was considerable individual variation in results. Conclusion: Taking these changes into account, the indices gave a good prediction of the glaucomatous field status following cataract operation, which itself results in some increase in the underlying field defect.
Reproducibility of automatic standard digital analysis of lens opacities
Authors: Garrett SKM , Robman LD , McCarty CA , Thomas AP , McNeil JJ , Taylor HR 
Published: November 2007

Abstract Purpose: This study was designed to assess the repeatability of the standard analysis of images taken with the Nidek EAS‐1000 anterior segment analysis system (Nidek Co, Ltd, Japan). Methods: Participants in a large clinical trial (the vitamin E, cataract and age‐related maculopathy study) were asked to undergo two independent examinations to assess the repeatability of primary outcome measures. After pupil dilatation to at least 6.5 mm, 104 eyes were photographed using the retro‐illumination method and the slit‐beam method. Results: Intra‐class correlation coefficients were: slit images, R= 0.982; retro‐illumination images, R= 0.978. Conclusion: Repeatability of measurement of lens opacity from EAS‐1000 images using automated standard analysis was high.
Effects of surface topography on corneal epithelialization in vivo: A preliminary study
Authors: Xie Ruo Zhong , Sweeney Deborah F , Griesser Hans J , Steele Jack G 
Published: November 2007

Abstract Purpose: In this study we investigated the relationship between surface topography and initial epithelialization of synthetic lenticules in vivo. Methods: Millipore ultrafiltration membranes of three different pore sizes were used as model lenticule materials. The nominal membrane pore sizes were 0.1 μm, 0.45 μm, and 3 μm; the surface roughness increased in the same order. The membranes were coated with a thin layer of collagen I and implanted in a circular pocket of the anterior cornea of adult cats, and were clinically evaluated for the extent of epithelialization and the persistence of epithelial attachment. Results/Conclusions: It was demonstrated that a smooth surface appears more attractive for initial epithelialization than a rough surface in vivo.
Morphological variants in keratoconus: Anatomical observation or aetiologically significant?
Authors: Armitage JA , Bruce AS , Phillips AJ , Lindsay RG 
Published: November 2007

Abstract Purpose: Two morphological cone variants are identified in keratoconus: nipple and oval. The present study was designed to assess the impact of aetiological factors on cone morphology. Methods: As part of a prospective controlled study, keratoconic subjects from a suburban practice (n= 89) underwent videokeratograph examination and completed a questionnaire detailing aetiological factors. Results: Comparison of 95% confidence limits (CL: bootstrap method) for apical power between the two cone morphology groups showed no statistical significance. Oval cones were located at a greater eccentricity than nipple cones, as their definitions suggest. Associations between aetiological factors examined and the morphology of the cone were not significant (bootstrapped 95% CL). Conclusion: Despite the suggestion of morphological variants in keratoconus, the results of the present study suggest a common cone aetiology.
Culture and characterization of smooth muscle cells from porcine retinal microvessels
Authors: Mortimer B‐C , Yu D‐Y , Morgan WH , Alder VA 
Published: November 2007

Abstract Purpose: To establish long‐term cultures of retinal vascular smooth muscle cells for future studies of their functions under normal and diseased conditions. Methods: Smooth muscle cells (SMC) from porcine retinal microvessels were isolated and cultured. Results: Cells in culture retained the common biochemical characteristics of SMC propagated from other sources. The cells were large, polygonal, spindle shaped and demonstrated the presence of smooth muscle‐specific α‐actin. Post‐confluent cultures showed the ‘hill and valley’ multilayer growth characteristics. However, the growth rate was lower and the population doubling time was significantly larger than those reported for SMC propagated from big vessels. Conclusion: Retinal vascular SMC could be cultured separately from other cell types. The availability of this culture provides a unique model for functional and metabolic studies of the retinal vessels.
Attentional blink in global versus local attentional modes
Authors: Lawson ML , Crewther DP , Duke CC , Henry L , Kiely PM , West SJ , Crewther SG 
Published: November 2007

Abstract Purpose: Brain imaging studies have shown that global and local attention activate different areas of the brain, with implication for dependence of perception on attentional state. The aim of the present experiment was to investigate the duration of the attentional blink in global versus local attention. Methods: Rapid Serial Visual Presentation (RSVP) sequences of global/local stimuli were presented to 34 adult subjects who had to identify a target red figure followed by a determination of whether a certain probe letter, ‘X’ (specified to be either the global or local form), was present in the subsequent string of letters. Results: Attentional blinks were longer than any previously reported (1.67 s global; 2.97 s local) and were significantly different. Thus, the length of the attentional blink is dependent on the attentional state of the subject. Conclusion: This pattern of results is consistent with the hypothesis that global attention mechanisms receive predominantly M‐pathway input.
The Craik‐O'Brien‐Cornsweet effect and brightness induction both proceed by the spreading of brightness information
Authors: Maddess T , Davey MP , Srinivasan MV , James AC 
Published: November 2007

Abstract Background: The Craik‐O'Brien‐Cornsweet effect (COCE) is a visual illusion where the luminance of image boundaries sets the apparent brightness of enclosed regions. The COCE may be produced by the cortex constructing the observed brightness through a lateral ‘filling‐in’ process: propagating brightness information from the edges of the enclosed regions towards their centres. Any such filling‐in process would imply a speed of propagation. Methods: Data on the propagation speed of brightness information in two different brightness induction effects are compared using a multivariate regression analysis. Results/Conclusion: We demonstrate similar non‐zero speeds for the COCE and for a brightness contrast effect.