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Introduction: This study compares the outcome and complications of integrated hydroxyapatite implant and non-integrated orbital implants following enucleation in Asian patients., Materials and Methods: This is a retrospective study of enucleated patients with coralline hydroxyapatite implants versus non-integrated implants (acrylic, glass and silicone) at the Singapore National Eye Centre from January 1991 to December 2000. The outcomes measured were implant migration, extrusion, socket infection, conjunctival dehiscence and implant exposure. Statistical analysis was done using the 2-sample t-test., Results: Twenty-one patients had the hydroxyapatite implant and 38 non-integrated implants (27 acrylic, 9 glass and 2 silicone). The mean duration of follow-up was 2.7 years and 4 years for the hydroxyapatite implant and non-integrated implants respectively. Three patients with pre-existing severe socket contracture before enucleation surgeries were excluded from the study. Four cases of implant migration, 4 cases of implant extrusion and 3 cases of socket infection were encountered; all were sockets fitted with non-integrated implants. There was a higher rate of conjunctival dehiscence for sockets with hydroxyapatite implants (6 out of 21) compared to sockets with non-integrated implants (3 out of 35). This was statistically significant (P = 0.048)., Conclusions: Implant complications of migration, extrusion and socket infection were found in non-integrated implants and none in coralline hydroxyapatite implants, which had a significantly higher rate of conjunctival dehiscence. Most of these were easily managed with only a small number progressing to implant exposure.

Purpose: To examine the baseline retina and optic disk characteristics in children., Design: Cross-sectional study., Methods: Subjects included 679 subjects with myopia and 100 with emmetropia, aged 8 to 13 years. Digital retina imaging and cycloplegic autorefraction were conducted to look for signs of retinal degeneration. Other outcome measures were vertical and horizontal cup-to-disk (CD) ratios, CD area ratio, parapapillary atrophy (PPA)-to-disk area ratio, and disk rotational angle., Results: The prevalence of lattice degeneration was 0.15% (95% confidence interval: 0.008-1.00). No other retinal abnormalities were detected. Increased PPA-to-disk area ratio was associated with increased axial length, increased myopia severity, and increasing age. Cup-to-disk ratios were smaller in subjects with myopia compared with those with emmetropia, but this did not correlate with severity of myopia. In subjects with severe myopia, the upper pole of the disk was rotated away from the fovea but to lesser extent than in those with emmetropia or milder myopia., Conclusions: Apart from PPA, degenerative features were not commonly found in this study.

A 35-year-old woman who reported persistent significant vision loss for 3 years after taking the antidepressant nefazodone was referred for electrophysiological assessment of vision. The vision changes included reduced acuities, reduced colour vision and visual field constriction in both eyes and were thought to be associated with the use of nefazodone for 6 - 8 weeks, 3 years earlier. Multifocal electroretinograms and visual evoked potentials were recorded using the Visual Evoked Response Imaging System (VERIS) to investigate the nature and site of the neural deficit. The summed retinal response showed a normal a- and b-wave latency and amplitude, however, the retinal topographic mfERGs showed a severe depression of the macular response in both eyes. The cortical topographic multifocal VEP mapping also showed a central depression in the right eye compared with the left. Two-frame motion and pattern custom mfVEP were also measured to assess different forms of cortical processing and especially of motion as nefazodone has previously been associated with image persistence with moving stimuli. The responses to two frame-motion showed signs of abnormality. Thus these results suggest that the primary locus of neural damage is retinal and is likely to have resulted from neurotoxicity. Other competing hypotheses such as hysterical blindness must be ruled out.

Benzoyl peroxide (BPO) is a commonly used drug in the treatment of acne vulgaris, but it induces unwanted side effects related to stratum corneum (SC) function. Since it has been recently shown to oxidize SC antioxidants, it was hypothesized that antioxidant supplementation may mitigate the BPO-induced SC changes. To test this, 11 subjects were selected to be topically supplemented with alpha-tocotrienol (5% w/vol) for 7 d on defined regions of the upper back, while the contralateral region was used for vehicle-only controls. Starting on day 8, all test sites were also treated with BPO (10%) for 7 d; the alpha-tocotrienol supplementation was continued throughout the study. A single dose of BPO depleted 93.2% of the total vitamin E. While continuing the BPO exposure for 7 d further depleted vitamin E in both vehicle-only and alpha-tocotrienol-treated sites, significantly more vitamin E remained in the alpha-tocotrienol-treated areas. Seven BPO applications increased lipid peroxidation. Alpha-tocotrienol supplementation significantly mitigated the BPO-induced lipid peroxidation. The transepidermal water loss was increased 1.9-fold by seven BPO applications, while there was no difference between alpha-tocotrienol treatment and controls. The data suggest that alpha-tocotrienol supplementation counteracts the lipid peroxidation but not the barrier perturbation in the SC induced by 10% BPO.

Topical steroidal anti-inflammatory drugs (SAID) and non-steroidal anti-inflammatory drugs (NSAID) are known to affect fluid balance. The effects of twice daily topical applications of Maxidex (dexamethasone, a SAID), Acular (ketorolac, a NSAID), and saline were examined biometrically on the development of refractive errors and eye growth in chicks raised from days 3-12 wearing either a monocular +10 D, 0 D, or -10 D lens. Biometric analysis showed that neither SAID nor NSAID nor saline affected refractive error compensation but that the anti-inflammatory drugs affected eye growth. In chicks reared with a +10 D lens, dexamethasone induced a decrease in axial length (AL), vitreous chamber (VC) and anterior chamber (AC) depth, while ketorolac only induced a decrease in AC. In -10 D lens chicks dexamethasone again induced a decrease in AL and VC, but did not affect AC depth, whereas ketorolac only induced an increase in AC depth. Taken together, these results suggest that anti-inflammatory drugs can induce changes in ocular size without affecting refractive state and, as such, have implications for the management of progressive myopia.

Aim: To determine the surgical approaches and adjunctive therapy es currently used by Victorian ophthalmologists for the treatment of primary and recurrent pterygia., Method: Ophthalmologists practising in Victoria were asked to complete a written survey relating to their experience with pterygium surgery., Results: Responses were received from 142 of 165 ophthalmologists surveyed (86%). Of these, 107 (75%) had performed at least one pterygium operation during the preceding 2 years. Excision followed by beta irradiation was the most commonly performed procedure for both primary (57%) and recurrent (35%) pterygia. The next most commonly performed procedure for primary pterygia was excision leaving bare sclera (15%) and, for recurrent pterygia, excision with autologous conjunctival transplantation (26%). Considerable variation was observed in surgical technique, choice of adjunctive therapy, postoperative care and in the surgeons' estimates of the frequency of major complications., Conclusion: Although there is little consensus regarding the surgical management of pterygium, beta irradiation remains the most commonly used adjunctive therapy in Victoria.

Objective: This study examined glucose metabolism in the anterior and posterior cingulate cortex in schizophrenia., Method: Fifty unmedicated male schizophrenic patients and 24 normal men were studied with positron emission tomography., Results: Compared with the normal men, the schizophrenic patients had lower relative metabolic rates in the anterior cingulate and higher rates in the posterior cingulate., Conclusions: The findings suggest hypofunction in the anterior cingulate cortex in schizophrenia.

We previously obtained evidence indicating a genetic linkage marker for schizophrenia and related disorders (two-point lod score = 3.72, P = 0.01) on the short arm of chromosome 5(5p14.1-13.1) in one large pedigree. Automated computer algorithms were used to edge the brain and measure the volume of the ventricles, regional sulcal atrophy, and skull size and shape in the original nuclear family members. Of the 11 subjects who underwent computed tomography, six (three schizophrenic, two with schizotypal personality disorder, and one unaffected) carried the marker allele that co-segregated with schizophrenia-related disorders, while five (all unaffected) did not. The family members with the marker allele linked to schizophrenia-related disorders (n = 6) had significantly (P < 0.05) larger ventricle-brain ratios (VBRs) and more fronto-parietal atrophy (controlling for age) than the family members lacking the schizophrenia-related marker allele (n = 5). The three individuals with the largest VBRs all carried the marker, although they received diagnoses of no schizophrenia-related disorder, schizotypal personality disorder, and schizophrenia. Regional cortical values indicative of cerebrospinal fluid content were higher in the frontal and parietal regions of family members carrying the marker. The hypothesis that genetic linkage is associated with structural brain pathology is difficult to test because of all the potential compounding factors. Our findings suggest the possibility that, in this family, relatively enlarged VBR and fronto-parietal atrophy, as determined by computed tomograph, may be associated with a schizophrenia-related gene and present susceptibility to schizophrenia-related disorders. In addition to a replication of these findings in other similarly linked families yet to be identified, further studies using higher resolution structural and functional neuroimaging techniques will be required.