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Chemical control trials against Phytophthora capsici (Leon) on pepper cultivations in Morocco. Pepper protection trials against collar and root rot have been undertaken under laboratory and culture conditions using Aliette (80 % of phosethylaluminium) and Ridomil M 58 (10 % of metalaxyl associated to 48 % of maneb). It has been proved that, contrary to Ridomil M 58, Aliette does not protect the hostplant when the Phytophthora capsici (Leon) zoospores are used as inoculum. But both fongicides are active when inoculating with a mycelian suspension. Trials undertaken under plastic glasshouses confirmed the laboratory results both with an artificial inoculation and with a natural one on contaminated soil. Only Ridomil M 58 provides satisfactory protection during the first weeks after the treatment. When disease propagation conditions are particularly favorable (permanent presence of an active inoculum source), the protection given by repeated Ridomil M 58 applications gradually disappears after a few weeks.

Ilicicolins D, E, F, dechloroilicicolin D, ascofuranone and arthrichitin were isolated from the fermentation broth of Nectria sp (HIL Y 90 3333). The ilicicolins showed good fungicidal activity in planta. [ABSTRACT FROM AUTHOR]

Purpose: To determine whether constriction of proximal arterial vessels precedes involution of the distal hyaloid vasculature in the mouse, under normal conditions, and whether this vasoconstriction is less pronounced when the distal hyaloid network persists, as it does in oxygen-induced retinopathy (OIR)., Methods: Photomicrographs of the vasa hyaloidea propria were analysed from pre-term pups (1-2 days prior to birth), and on Days 1-11 post-birth. The OIR model involved exposing pups to approximately 90% O(2) from D1-5, followed by return to ambient air. At sampling times pups were anaesthetised and perfused with india ink. Retinal flatmounts were also incubated with FITC-lectin (BS-1, G. simplicifolia,); this labels all vessels, allowing identification of vessels not patent to the perfusate., Results: Mean diameter of proximal hyaloid vessels in pre-term pups was 25.44 +/- 1.98 microm; +/- 1 SEM). Within 3-12 hrs of birth, significant vasoconstriction was evident (diameter:12.45 +/- 0.88 microm), and normal hyaloid regression subsequently occurred. Similar vasoconstriction occurred in the O(2)-treated group, but this was reversed upon return to room air, with significant dilation of proximal vessels by D7 (diameter: 31.75 +/- 11.99 microm) and distal hyaloid vessels subsequently became enlarged and tortuous., Conclusions: Under normal conditions, vasoconstriction of proximal hyaloid vessels occurs at birth, preceding attenuation of distal hyaloid vessels. Vasoconstriction also occurs in O(2)-treated pups during treatment, but upon return to room air, the remaining hyaloid vessels dilate proximally, and the distal vessels become dilated and tortuous. These observations support the contention that regression of the hyaloid network is dependent, in the first instance, on proximal arterial vasoconstriction.

Background: Amblyopia is a public health problem, usually amenable to treatment if detected early. Photoscreeners are camera-based instruments which can detect risk factors for amblyopia such as squint, refractive errors and media opacities., Objective: To evaluate two commercially available photoscreeners, namely the MTI photoscreener (Medical Technology, Iowa City, IA, USA) and the Fortune Optical VRB-100 (Fortune Optical, Padova, Italy) videophotorefractor, in a selected childhood population, having a high prevalence of amblyopia, before undertaking a full-scale trial in the general population., Subjects and Methods: The study design was a double-masked study. One-hundred and five children aged between 12 and 44 months with either normal vision or known visual disorders were photoscreened without cycloplegia using the Fortune and the MTI photoscreeners. Each child had a full ophthalmic examination either on the day of screening or in the preceding 6 months. Risk factors were: any manifest strabismus (squint), hypermetropia >3.5 D, anisometropia > or =1 D sphere, myopia > or =2 D sphere, astigmatism > or =2 D, media opacity or fundus abnormality affecting vision. The prevalence of risk factors for amblyopia was 60%. Photoscreen images were reviewed by two independent masked observers for indicators of amblyopiogenic risk factors and compared to the full ophthalmological examination to determine sensitivity and specificity for each instrument., Results: Sensitivities and specificities for the detection of risk factors for amblyopia were as follows. Fortune photoscreener: reader 1, sensitivity 60%, specificity 75%; reader 2, sensitivity 68% specificity 86%. MTI photoscreener: reader 1, sensitivity 56%, specificity 79%; reader 2, sensitivity 61%, sensitivity 86%. The results for reader 1 and 2 showed no significant differences for either instrument., Conclusion: Both instruments performed unsatisfactorily in a study population aged 1-4 years with a high prevalence of amblyopiogenic risk factors. Accordingly, we do not believe that either instrument can be recommended to screen for eye disorders in children between the ages of 1 and 4 years because the low prevalence of amblyopia in this population demands very high sensitivity and specificity in order to avoid inappropriate over- or under-referral.

Background: Retinoblastoma is the commonest intraocular tumour of childhood with the majority of cases being diagnosed before 5 years of age. Late presentation of retinoblastoma is rare., Case History: A healthy 16-year-old Caucasian girl presented with a 1-day history of blurred vision in the left eye. Examination revealed an inferonasal mass in the left retina with an overlying haemorrhage and vitreous seeding. Imaging studies revealed a 5-mm densely calcified opacity. Other investigations, including cerebral spinal fluid examination, bone marrow aspirate trephine, toxocara serology and serum protein studies, were normal. After considering the differential diagnoses such as toxocariasis and Coat's disease, a diagnosis of late-presenting retinoblastoma was made. The patient subsequently underwent enucleation with a primary orbital implant. The diagnosis was confirmed histopathologically., Conclusion: Late presentation of retinoblastoma is uncommon but can be a cause of acute visual impairment in the non-paediatric age group. Retinoblastoma should be considered in the differential diagnosis of a fundal mass in any age group.

Peters anomaly is a congenital corneal opacity with underlying defects in the posterior stroma, Descemets membrane and corneal endothelium. It is a disorder resulting from abnormal migration or function of neural crest cells and may include abnormalities of other anterior segment structures, such as the lens and iris. We report a family in which anterior segment abnormalities, including Peters anomaly and cataracts, were inherited in an autosomal dominant fashion. Although the PAX6 gene on chromosome 11 has been shown to be involved in some cases of anterior segment developmental defects, we found no evidence that the condition in this family is linked to the PAX6 gene. Identification of this gene will indicate another gene with major involvement in the development of the anterior segment of the eye.

Laser photocoagulation has become the standard for treatment of retinopathy of prematurity. In general, it has been found to be a safe and effective means of retinal ablation. We report a case of angle-closure glaucoma in an infant after diode laser treatment for retinopathy of prematurity, which required bilateral surgical peripheral iridectomies.

Purpose: To report the results of treatment of a series of patients with superior oblique overaction using the superior oblique silicone tendon-expander technique., Methods: A chart review of 17 patients with superior oblique overaction who had a total of 26 silicone tendon-expander procedures was conducted., Results: Mean preoperative degree of superior oblique overaction was +2.7. 92% of eyes had mild (+1) or no residual overaction at last postoperative assessment (follow-up range: 6 to 59 months). Of 15 patients with preoperative A-pattern of 10 prism diopter (delta) or more, only two patients (13%) had A-pattern of 10 delta or more at last assessment. Of 13 patients with preoperative hypotropia in primary position, five patients (38%) had no vertical deviation in primary position, and seven patients (54%) had persistent, but less vertical deviation in primary position at last assessment (mean reduced from 11 delta to 4 delta). No patient manifested superior oblique palsy at their last postoperative assessment., Conclusions: We believe that the superior oblique tendon-expander technique should be strongly considered for the treatment of superior oblique overaction associated with A-pattern or hypotropia in primary position, because it has a high success rate and a low incidence of postoperative complications. Consecutive superior oblique underaction did not occur in this series.

Objective: To evaluate two photoscreeners in a childhood population., Study Design: Double-masked study., Subjects and Method: One hundred and thirteen children aged between 11 and 44 months with either normal vision or known visual disorders were photoscreened without cycloplegia by the Otago and Dortmans (prototype) photoscreeners. Each child had a full ophthalmological examination either on the day of screening or in the proceeding six months. Photoscreen images were reviewed by an independent observer for indicators of amblyopiogenic risk factors, and compared to the full ophthalmological examination to determine sensitivity and specificity for each instrument., Results: The Otago photoscreener returned a sensitivity of 70% and specificity of 82% for the detection of amblyopiogenic risk factors. The Dortmans photoscreener returned a sensitivity of 70% and specificity of 90%. Both photoscreeners were portable and easily operated., Conclusion: Children can be screened successfully for amblyopiogenic risk factors with these photoscreening systems. Further evaluation is required to determine specificity in a normal population. This would also provide information on the potential usefulness of photoscreeners in a cost effective childhood vision screening program.

Purpose: We present the results of anterior transposition of the inferior oblique in a series of patients with inferior oblique overaction and dissociated vertical deviation (DVD)., Patients and Methods: We performed a retrospective study of 37 procedures on 21 patients who had unilateral or bilateral inferior oblique anterior transpositions. Before surgery, patients had +1 to +3 inferior oblique overaction and +1 (< 10 PD) or +2 (10 PD-20 PD) degree of DVD. The inferior oblique insertion was transposed to between 2 mm posterior to and 2 mm anterior to the temporal border of the inferior rectus insertion. Mean follow-up period was 27 months., Results: Incidence of inferior oblique overaction of +2 or more was reduced from 84% before surgery to 16% at last postoperative assessments. Some 43% of eyes had no inferior oblique overaction and 86% had an improvement in the degree of inferior oblique overaction. At last assessments, 57% of eyes had no evidence of DVD and 68% of eyes had no evidence of DVD or an improvement in the degree of DVD. No patient who had unilateral anterior transposition developed hypotropia in primary position and there was no evidence of inferior oblique underaction in any patient at last assessment. Three patients requiring repeat inferior oblique surgery are discussed, including one patient who developed a large Y-pattern exotropia after bilateral anterior transposition of the inferior obliques., Conclusions: Inferior oblique anterior transposition has a place in the treatment of coexistent inferior oblique overaction and dissociated vertical deviation.

Purpose: To establish the sensitivity and specificity of the Bruckner reflex (comparison of the fundus red reflexes) in the detection of amblyopia or its risk factors., Methods: A single masked study using a medical student's diagnostic ability against the gold standard of a full clinical examination by a paediatric ophthalmologist., Setting: A university teaching hospital outpatient facility., Patients: Three hundred and one patients consecutively referred for ophthalmic assessment., Results: The sensitivity of the test for the detection of children with amblyopia risk factors was 86% and the specificity was 65%. Of 70 children with a definite diagnosis of amblyopia, the sensitivity of the test was 95%., Conclusions: The Bruckner reflex is a useful screening test for primary eye care personnel. However, there is a significant false-positive rate which will result in unnecessary referrals. We recommend that it form part of a battery of tests, including, for example, the modified base down prism test, which are useful in assessing the vision of preverbal children.

Many techniques have been described for the detection of functional visual loss. We report four cases in which Ishihara pseudo-isochromatic colour plates gave objective evidence of functional vision loss. In all cases the patients were able to read the first test pattern (No. 12), but could not distinguish any of the following pseudo-isochromatic numbers (plates 2-17). However, they experienced no difficulty in tracing the winding lines (plates 18-24), demonstrating that they in fact had normal colour vision.

The use of tinted lenses as a method to improve reading skills in children with dyslexia has been a controversial issue in recent years. The purpose of the present study was to determine if tinted lenses cause a measurable improvement in the reading performance of dyslexic children. Twenty-four children aged 8 to 12 years participated in the study. Dyslexia was diagnosed in all children by psychological evaluation, and these children underwent an ophthalmic evaluation for inclusion into the study. Participants were graded for speed and accuracy as they read through spectacle frames that contained red-, blue-, yellow-, and green-tinted lenses, a neutral-density lens, and empty frames. All lenses for each subject were of the same density level, with subjects alternately distributed to one of two densities tested (0.12 or 0.30 log units). Each child was asked to select the lens condition that subjectively improved reading ability at the conclusion of testing. One-way analysis of variance of reading performance showed neither improvement nor deterioration attributable to lens color or density when applied to error rates (F = 1.73, P = .14 for a density of 0.12; F = 0.28, P = .92 for a density of 0.30) or to reading rates (F = 0.98, P = .44 for a density of 0.12; F = 0.81, P = .55 for a density of 0.30). In addition, the lens condition that was subjectively preferred by each child did not correlate with actual reading performance (chi 2 = 3.83, not significant; 11.07 needed for significance at P = .05).

Newborn mice exposed to high (greater than 98%) ambient oxygen during the newborn period and subsequently removed to room air will develop a proliferative retinopathy which mimics the neovascular component of acute retinopathy of prematurity. In this paper, we report preliminary ultrastructural findings on the vitreous new vessels in the mouse model of oxygen-induced retinopathy, and argue that the model is appropriate for research on non surgical treatments for ROP in particular and angiogenesis in general.

We have carried out a randomised prospective controlled trial of the effect of tinted lenses on the reading ability of 24 non-asthmatic dyslexic children aged between nine and twelve years. Reading ability was assessed using the Neale Analysis of Reading. After one school term, there was no significant difference in the change in reading age between treatment and control groups. After two school terms (approximately six months), only 11 children (44%) were still wearing the glasses. Of 381 suitable subjects for entry into the study, 208 were excluded because of a diagnosis of asthma (to avoid effects of medication on cerebral function). As a result, we may have excluded subjects who would have responded favourably to tinted lenses.

A number of chemically unrelated substances have been compared for their neovasculogenic activity by two different in vivo tests, and for their ability to induce cultured endothelial cell migration and proliferation. Formyl methionyl leucyl phenylalanine, copper ions, heparin, adenosine diphosphate, and low-molecular-weight bovine endothelium stimulating factor were all neovasculogenic by the corneal pocket assay. By the chorioallantoic membrane assay, copper ions and formyl methionyl leucyl phenylalanine were not detectably neovasculogenic. By the same assay it has been possible to demonstrate angiogenic activity in bovine endothelium stimulating factor that is distinguishable from copper ions. This bovine factor, in contrast to the other agents, induced marked endothelial cell migration and also proliferation and may belong to a special class of agents which represents direct acting angiogenic activity.

Combined hamartoma of the retina and retinal pigment epithelium (RPE), is a rare, benign, congenital fundal lesion which contains a mixture of glial tissue, blood vessels and pigment epithelium. Such tumours are variably pigmented and may be wrongly diagnosed as malignant melanoma or retinoblastoma. We report two cases which were located in the periphery of the fundus and which produced a dragged disc appearance.

Eccentric photorefraction (EPR) is a simple photographic technique for detecting amblyopiogenic conditions. Previous EPR studies to detect refractive errors (RE) have demonstrated high sensitivity but poor predictive value. We have established new criteria for detecting RE involving quantifying retinoscopic reflex crescent widths, thereby achieving 67% predictive value with 100% sensitivity for detecting RE greater than or equal to +3.5 D in a clinical study of 69 children. Optical analysis of EPR shows that anticrescent width (light crescent-free portion of the pupil) is independent of pupil diameter. Quantifying anticrescent widths in the above clinical trial increased the predictive value to 85%. Schematic eye and human eye EPR studies verify the theoretical prediction that similar ability to detect refractive errors is maintained when the working distance and eccentricity (distance of light source from lens edge) are reduced. These improvements in EPR reduce its cost and improve its yield; both are essential for its introduction as an acceptable community screening tool.