bluuebunny/crossref_metadata_2025 huggingface dataset:
Choroidal melanoma: A review of the experience of the Sydney Eye Hospital Professorial Unit 1979–1995
Authors: Reader S , Grigg J , Billson FA
Published: November 2007

Purpose:This study examines 90 patients presenting with choroidal or ciliochoroidal melanoma to the Professorial Unit at the Sydney Eye Hospital. The indications for treatment, and the outcome for the eye and vision are presented together with an account of mortality and the incidence of metastases.

Methods:A retrospective analysis of 90 choroidal melanoma patients managed by one surgeon over a 16‐year period was undertaken. Initial findings, investigations performed, incidence of metastatic disease, treatment received and complication rates and mortality, where applicable, were recorded.

Results:The group was followed for an average of 64 months (range, 5–172 months). Primary treatment was with either Iodine125(1251) brachytherapy, local excision or enucleation. Radiation retinopathy was prominent in1251 cases resulting in poor visual acuity when the tumour resided in the posterior pole. Local excision even of large tumours was effective particularly if peripheral. Overall metastatic disease was seen in 11% with 5‐year survival rates for the metastatic group being 10%. Prognosis after diagnosis of metastases was poor.

Conclusions:Specific therapy for choroidal melanoma must relate to the size and location of the tumour at the time of diagnosis. Visual outcome relates directly to the proximity of the tumour to the optic nerve and fovea. Metastatic disease latency can be prolonged; therefore caution about prognosis is required long after therapy is given. The 5‐year survival is encouraging with all forms of therapy. However, as the natural history of ocular melanoma is variable and not fully delineated it is important to monitor the effects of conservative therapy. Further long‐term survival data is required to distinguish whether one form of treatment is advantageous over the others, although case‐control studies are difficult for ethical and practical reasons. In this regard the Collaborative Ocular Melanoma Study (COMS) will provide further evidence for the safety and efficacy of conservative therapy with brachytherapy compared to enucleation.
Orbital decompression for thyroid orbitopathy
Authors: McNab AA
Published: November 2007

Background:

Severe thyroid orbitopathy may result in optic neuropathy, corneal exposure and disfiguring proptosis, Orbital decompression has most commonly been performed for optic neuropathy, but with improved techniques, more patients are undergoing decompression for other indications.

Purpose: This report evaluates the results and morbidity of orbital decompression for thyroid orbitopathy performed by one surgeon.

Methods: The records of 33 patients (53 orbits) undergoing orbital decompression for thyroid orbitopathy were analysed for changes in visual acuity and colour vision (where the indication was optic neuropathy) and reduction in proptosis. Complications were also analysed.

Results: Visual acuity and colour vision improved in all 33 eyes with optic neuropathy in the short term postoperative period (4 weeks), but later deteriorated in five eyes (6.6%) of 4 patients (19%). Proptosis decreased by a mean 5.3 mm (range, 1–10). Diplopia developed or worsened overall in 10 of 33 patients (30%), but only in one of 12 (8%) where the indication was cosmesis or corneal exposure. Diplopia improved in 2 of 33 (6%). All patients with symptomatic diplopia achieved binocular single vision in a useful range after one and sometimes two squint procedures. No patient lost vision as a result of surgery.

Conclusions: Orbital decompression is effective in improving vision in most patients with thyroid optic neuropathy, but induces or worsens diplopia in a high proportion of these patients. Proptosis can be effectively and dramatically improved.
Congenital optic pits and central serous chorioretinopathy
Authors: Chen M‐S , Tsai W‐F
Published: November 2007

Purpose: The reporting of the occurrence of central serous chorioretinopathy in a patient with congenital optic pits.

Methods: A 31‐year‐old man complained of blurred vision in the right eye for 1 week. He had a visual acuity of 20/25 in the right eye. He underwent ophthalmoscopy and fluorescein angiography.

Results: Ophthalmoscopy revealed serous detachment of macula with its margin not adjacent to the margin of optic disc. Fluorescein angiography showed a typical ink blot appearance of dye leakage.

Conclusions: Central serous chorioretinoapthy can occur in the patient with congenital optic pits. Detailed ophthalmoscopic and fluorescein angiographic studies are necessary to establish the diagnosis of optic pits associated with macular detachment. Various mechanisms have been reported to explain the serous macular detachment in patients with optic pits including vitreous and cerebrospinal fluid leakage through the optic pit and from there into the subretinal space. The present case further denotes that central serous chorioretinopathy in the presence of optic pits can be due to leakage from the retinal pigment epithelium.
Nanophthalmos with longstanding choroidal effusion and serous retinal detachment
Authors: Han Lirong , Cairns JD
Published: November 2007

Purpose: To report a typical case of nanophthalmos with uveal effusion and local serous retinal detachment followed for 1 year.

Methods: Clinical ocular examinations included vision, refraction, corneal diameter; anterior chamber depth, intraocular pressure, fundoscopy, A/B scan ultrasonography and gonioscopy.

Results: Both eyes were hypermetropic with small corneas and shallow anterior chambers. Decreased axial length and thickened sclera were also found. There were peripheral choroidal effusions and local serous retinal detachments as well. The patient declined any surgery that was offered. No significant change in either eye was found after I year follow‐up.

Conclusion: This case illustrates that the progress of choroidal effusion and retinal detachment in nanophthalmos may be very slow and even non‐progressive for at least 1 year. In these cases sclerectomy and or sclerotomy may be delayed without undue immediate risk to the vision.
Smooth pursuit development in infants
Authors: Jacobs Mark , Harris Christopher M. , Shawkat Fatima , Taylor David
Published: November 2007

Purpose: We set out to assess the development of pursuit eye movements in normal infants in an objective, longitudinal fashion. We asked whether smooth pursuit (SP) was present under 2 months of age and how the saccade ratio changed with increasing infant age.

Methods: Smooth pursuit was recorded longitudinally from 25 infants aged 1–7 months, using DC electro‐oculography, in a clinically practical manner. Four uninstructed adults acted as controls.

Results: Smooth pursuit was present under 2 months of age. The gain of SP increased with increasing infant age. However, it had still not reached adult levels by 6 months of age. Latency decreased with increasing infant age. Monocular SP asymmetry was present in the younger infants.

Conclusions: Smooth pursuit is present under 2 months of age, but at 6 months SP has still not reached adult levels. The traditional model of SP development is questionable.
Traumatic retinopathy resembling acute macular neuroretinopathy
Authors: Gillies M , Sarks J , Dunlop C , Mitchell P
Published: November 2007

Background: Acute macular neuroretinopathy (AMNR) is an uncommon disease of uncertain aetiology. We report on four males who developed unilateral changes following trauma which closely resembled acute macular retinopathy.

Methods: Retrospective review of selected cases.

Results: Four male patients developed a central or paracentral scotoma immediately or soon after an accident in which they suffered moderately severe bodily injury without direct ocular trauma. Vision was reduced in three patients. All four patients had characteristic well‐circumscribed, dark macular lesions best seen using red‐free light. The lesions cleared slowly in the two cases who returned for review.

Conclusions: A picture that closely resembles AMNR may be seen after trauma. The mechanism may involve a sudden rise in ocular venous pressure. This may be an unrecognized cause of visual loss after non‐ocular trauma which may be regarded as functional. The subtle retinal lesions may be overlooked unless the fundi are examined in red‐free light and the macular dark areas are compared.
Magnocellular and parvocellular visual pathways are both affected in a macaque monkey model of glaucoma
Authors: Vickers JC , Hof PR , Schumer RA , Wang RF , Podos SM , Morrison JH
Published: November 2007

Purpose: Neurochemical changes in nerve cells were investigated in the lateral geniculate nucleus (LGN) and primary visual cortex of macaque monkeys with experimentally induced glaucoma.

Methods: Glaucomatous damage was induced in one eye of experimental animals by elevation of intraocular pressure following laser burns to the trabecular meshwork. Staining for the metabolic marker cytochrome oxidase, as well as immunolabelling for the neuronal markers synaptophysin and neurofilament proteins, was conducted on sections of the LGN and primary visual cortex.

Results: In the LGN, staining for cytochrome oxidase and immunolabelling for synaptophysin were reduced in the parvocellular and magnocellular layers that received input from the glaucomatous eye and neurofilament protein labelling was reduced in the parvocellular layers. Cytochrome oxidase staining demonstrated the presence of denervated ocular dominance columns in layer IVC of the primary visual cortex of experimental animals.

Conclusions: Pre‐ and post‐synaptic neurochemical alterations in the magnocellular and parvocellular visual pathways of the brain are associated with experimentally induced glaucoma in macaque monkeys.
Knowledge and beliefs about common eye diseases
Authors: Attebo Karin , Mitchell Paul , Cumming Robert , BMath Wayne Smith
Published: November 2007

Purpose: To ascertain the level of knowledge of common causes of blindness in an adult Australian population and to relate this to use of eye care services.

Methods: A population‐based study of common eye diseases in an urban population aged 49 years or older was conducted. The questions were concerned with the awareness and knowledge of and the ability to describe three common eye diseases, namely cataract, glaucoma and agerelated macular degeneration (AMD).

Results: Awareness of cataract (98%) and glaucoma (93%) were high in this population, but awareness of AMD was low (20%). Among people who were aware of the target eye disease, only 29% showed some knowledge of glaucoma, 26% showed some knowledge of AMD and 20% showed some knowledge of cataract; this was also low in people who had previous eye treatment, such as cataract surgery. Knowledge was related to education level, occupational prestige and knowledge of other eye diseases. After excluding people with a previous eye disease diagnosis, those people who were aware and had some knowledge of eye disease accessed eyecare services more frequently.

Conclusions: Knowledge of common eye diseases is generally lacking. Age‐related macular degeneration is the leading cause of blindness in Australia, yet only 20% of the present study population had heard of it. As there are often no early symptoms for glaucoma, community awareness of this disease and the need for screening of people at risk may allow timely diagnosis and more effective therapy before advanced visual field loss has occurred. An informed public is more likely to present earlier with visual symptoms before irreversible visual loss has occurred and is more likely to comply better with recommended therapy.
Aeromonas sobria endophthalmitis
Authors: Lee Lawrence R , O'Hagan Stephen , Pra Mark Dal
Published: November 2007

Background:
Aeromonas sobria causes a rare Gram‐negative bacterial water‐borne infection. It has been found in waters of North Queensland and South‐east Asia. Of all Aeromonas species, A. sobria is the most virulent and invasive and has been reported to cause soft tissue infection and corneal ulcer.

Methods: A 14‐year‐old Caucasian male from North Queensland presented following a penetrating eye injury in which a water bird (cormorant species) had pecked his eye while he was fishing. A fulminant endophthalmitis developed despite treatment with intravenous, intravitreal and topical antibiotics and initial wound repair. Enucleation was performed.

Results:
Aeromonas sobria was isolated from the vitreous aspirate.

Conclusion:
Aeromonas sobria infection should be suspected in water‐contaminated penetrating eye injuries. The prognosis in this case was poor.
Growth of Gram‐negative bacteria in a simulated ocular environment
Authors: Cowell BA , Willcox MDP , Schneider RP
Published: November 2007

Purpose:

Gram‐negative bacteria are major pathogens in the ocular environment, especially when contact lenses are worn. The source of many of these organisms, including Pseudomonas aeruginosa, is thought to be environmental.

Methods:

A defined medium is described here that resembles both tear fluid and the environment they are derived from.

Results:

Gram‐negative ocular bacteria were found to grow successfully in this medium. Bactericidal tear proteins were added to this medium and pathogenic strains were not only able to resist their effects but were able to use them for growth.

Conclusion:

Utilizaton of tear proteins for growth may be an important virulence factor of pathogenic bacteria in the ocular environment.
Role of tear fluid in the growth of Gram‐negative bacteria on contact lenses
Authors: Williams TJ , Willcox MDP , Schneider RP
Published: November 2007

Incidents of CLARE (contact lens induced acute red eye) are associated with high numbers of Gram‐negative bacteria on the lens surface. This study found that most strains of bacteria implicated in CLARE adhere poorly to the lens surface regardless of whether the lens surface was clean or had been worn in the eye. The high numbers of bacteria on the lens surface result from bacterial growth on the lens surface after adhesion has occurred. Using an artificial tear formulation and real tears, this study demonstrated that the tear fluid provides the necessary nutrients required for bacterial growth.
Ocular microbiota and polymorphonuclear leucocyte recruitment during overnight contact lens wear
Authors: Stapleton F , Willcox MDP , Sansey N , Holden BA
Published: November 2007

Bacterial 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

Purpose:

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

There 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

There 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

A 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

Purpose:

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 diameter

Conclusions:

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

Purpose:

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

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

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

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

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

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

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

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

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

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

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

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

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

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.
Electrophysiology: A review of signal origins and applications to investigating glaucoma
Authors: Graham Stuart L , Klistorner Alexander
Published: November 2007

Because different electrophysiological responses can be isolated to different retinal and cortical cell types and levels, the proportion in which the different signals are reduced can reflect the primary areas of damage. The knowledge of electrophysiology component sources can thus be applied when examining ophthalmic disorders. The present review covers the proposed origins and the usefulness of the conventional electrophysiological responses. Their application to glaucoma is discussed, with particular reference to the pattern electroretinogram. In the second part of the current review, we present some recent developments that relate to the use of multifocal pseudorandomly stimulated recording. This technique enables a new approach to the electrical assessment of visual responses. Analysis for temporal non‐linearities and spatial distribution of the response throughout the visual field can be implemented. This type of recording has the potential to provide a method of objective visual field assessment in glaucoma and other disorders of the visual system.
Screening for diabetic retinopathy using a non‐mydriatic retinal camera in rural Victoria
Authors: Harper C Alex , Livingston Patricia M. , Wood Carolyn , Jin Cara , Lee Sue J. , Keeffe Jill E. , McCarty Cathy A. , Taylor Hugh R.
Published: November 2007

Purpose: To develop a screening programme for the early detection of diabetic retinopathy using non‐mydriatic retinal photography.

Methods: A community based screening service was offered to all people with known diabetes mellitus in selected townships in the LaTrobe and Goulburn Valleys in Victoria. At the local examination centre, basic sociodemographic information was collected as well as details of previous use of eye care services for the early detection of diabetic retinopathy. The examination included visual acuity (VA), glycosylated haemoglobin level and Polaroid photographs of each fundus using a Canon CR5‐45NM non‐mydriatic retinal camera (Canon, Tochigiken, Japan). Dilating drops were not used. Photographs were subsequently reviewed and letters were sent to all participants (with copies to their general practitioners) with recommendations for appropriate follow up.

Results: A total of I 177 people with diabetes attended the screening service, which is estimated to be 40% of the total population with known diabetes in the study area. The mean age was 65 years (range 20–94 years); 559 (48%) people reported not having a dilated fundus examination within the past 2 years; 345 (29%) people had never had a dilated fundus examination. Of the 2354 eyes, 2126 (90%) of the photographs were gradable. A total of 704 people (60%) had normal VA and no evidence of diabetic retinopathy, 209 people (18%) had diabetic retinopathy, 101 people (9%) had evidence of other fundus pathology, 42 people (3%) had reduced acuity (< 6/18) in one or both eyes (with no fundus pathology evident) and 121 people (10%) had ungradable photographs in one or both eyes.

Conclusions: The present study demonstrates the usefulness of a screening programme with non‐mydriatic retinal photography as an adjunct to current eye care services for the early detection of diabetic retinopathy.
Horner's syndrome resulting from a prolonged abnormal posture during a coma
Authors: Thompson CG
Published: November 2007

Background: Horner's syndrome results from the impairment of the sympathetic nerve supply to the eye and orbit. Other nerve palsies from prolonged unchanged posture are well described, but Horner's syndrome following prolonged lateral flexion has only twice been seen previously and these cases were in association with anaesthesia.

Methods/Results: A case is described of Horner's syndrome resulting from a prolonged period of unchanged posture from an alcohol‐induced coma. A review of the anatomy of Horner's syndrome is presented.

Conclusion: To my knowledge, this is the first reported case of Horner's syndrome resulting from a coma.
A Cognitive Perspective on Entrepreneurship and the Firm
Authors: Loasby Brian J.
Published: November 2007

abstract  I propose to examine the theme of this Special Issue from the perspective of its treatment – and, of especial significance, its lack of treatment – within economics. In the course of this examination we shall observe that the concepts of entrepreneurship and the firm are generally kept separate, and attempt to explain why. I shall avoid any discussion of recent work, which is more productively left to my fellow contributors, choosing instead to devote the first half of my contribution to providing an analytical basis for the second half by exploring the problem of knowledge in economic systems, and relating this problem to the evolved nature of human beings and their relationship with their environment. In this exploration I shall rely almost entirely on the work of economists, though much of it was not directed to conventional economic issues.
Role Expectations and Middle Manager Strategic Agency
Authors: Mantere Saku
Published: November 2007

abstract Based on an analysis of 262 interviews, I argue that role expectations have the potential to both enable and constrain middle manager strategic agency. To explain why the same role expectations have contradictory effects on agency, I analyse enabling conditions corresponding to four strategic role expectations, based on Floyd and Wooldridge's work on middle manager roles. After presenting eight enabling conditions for strategic agency, specific to the four role expectations, I argue that the dominant functionalist view of strategic roles should be augmented from a middle manager viewpoint. I suggest a reciprocal view of strategic role expectations, which elucidates the tensions between dialogue, legitimacy and rationality within a set of strategic roles.
The geographic impact of ‘open skies’ policies on Trans‐Tasman air passenger service
Authors: Vowles Timothy M. , Tierney Sean
Published: November 2007

Abstract:  The goal of this paper is to examine the various geographic shifts occurring in New Zealand air passenger service as a result of the liberal aviation policies pursued by the country. A brief history of New Zealand air passenger travel both domestically and internationally will be followed by a more in‐depth investigation into the impacts of the single aviation market between New Zealand and Australia, first negotiated in 1992, subsequently altered in 1996 and, in its present form, agreed to in 2000. Particular attention is given to the increased competition that has arisen in the Trans‐Tasman market, making it one of the most heavily contested routes in global aviation. The Trans‐Tasman is analysed at a variety of levels, including airline competition, market growth, and fare changes that have occurred in the five years since the ‘full open skies’ agreement came into effect.
Workers, Workplaces and Working Hours
Authors: Bryan Mark L
Published: November 2007

This article uses the British Workplace Employee Relations Survey 1998 dataset to evaluate the importance of firm‐level factors in determining weekly hours of work in Britain, to analyse the amount of variation of hours within firms, and to assess whether workers are sorted into firms on the basis of hours. Nearly a third of the explained variation in weekly hours of work can be ascribed to firm‐level differences, which are unrelated to any observed worker characteristics. Firm‐level ‘policies’ are especially important in the private‐services sector. A further 40 per cent of variance can be attributed to the effect within firms of different occupation, skills and family characteristics. Finally, about a quarter of the explained variation in working hours is due to a sorting process of workers to firms, especially on the basis of skill and occupation.
Side by Side We Battle Onward? Representing Workers in Contemporary America
Authors: Givan Rebecca Kolins
Published: November 2007

As collective bargaining in the United States declines, diverse forms of worker representation are proliferating. Strategic dilemmas of representation are central to the diverse organizations and coalitions representing disparate aspects of workers' interests. Unions continue to bargain collectively, while forming alliances with other groups and providing an array of services to members. Other organizations and loose associations represent specific aspects of workers' interests and advocate on their behalf while stopping short of collective bargaining. This article compares the scope, objectives and methods of worker representation by unions and non‐bargaining actors. It argues that the key dilemmas of which workers to represent, over what issues and through which organizational forms, apply both to unions and to non‐bargaining actors, such as community organizations, and advocacy groups, which represent select interests of particular workers. These non‐bargaining actors are key strategic allies for unions. While these organizations do not take on collective bargaining, they are sometimes better positioned to represent other key needs and interests of workers. The legal‐political and mutual insurance needs of workers are sometimes well met by these emergent groups. However, these organizations do not, and cannot, provide the advantages of traditional collective bargaining.
Similarities and Differences between Leadership and Management: High‐Performance Competencies in the British Royal Navy
Authors: Young Mike , Dulewicz Victor
Published: November 2007

This paper describes the research, analysis and development of a model clarifying the similarities and differences in competencies and personality factors1 associated with effective Leadership and Management in the Royal Navy. A questionnaire study was conducted on a sample of 261 Officers and Ratings (Sailors). Their performance was rated through the organization's rigorous appraisal process, whilst competency and personality data were gathered through the Occupational Personality Questionnaire and the Leadership Dimensions Questionnaire. The results identify the common and unique relevance of specific competencies and personality factors and so provide an illuminating insight into the differences between the constructs of leadership and management. The critical factors related to effective leadership and management performance are also identified.