Showing papers in "British Journal of Ophthalmology in 1986"
TL;DR: The theoretical basis for the calculation of corneal refractive power from anterior curvature is considered and it is shown that the power can be calculated with sufficient accuracy from one simple formula provided the refractive index of the 'cornea' is 1.3315.
Abstract: The theoretical basis for the calculation of corneal refractive power from anterior curvature is considered. It is shown that the power can be calculated with sufficient accuracy from one simple formula provided the refractive index of the 'cornea' is 1.3315. It is suggested that keratometer readings should be calibrated with this value in order to increase the accuracy in intraocular lens calculation.
235 citations
TL;DR: Despite intensive follow-up and treatment, loss of useful visual acuity has occurred in 74% of the eyes six to 10 years after the start of the ocular symptoms.
Abstract: For the last decade we have observed and regularly followed 49 patients with the ocular type of Behcet's disease. Thirty-six patients were males and 13 were females. Regardless of whether the initial ocular presenting symptoms were in the anterior or posterior segment, both segments were involved within two years. Sterile hypopyon was recorded in 17 out of the 49 patients during the process of follow-up. In three of the patients hypopyon was the presenting symptom. Characteristically there was a lack of corneal or scleral involvement in the disease process. All patients responded initially to treatment with steroids, but 42 had a course of treatment with cytotoxic-immunosuppressive drugs for various lengths of time after 'resistance' to steroids developed. Although definitely effective in reducing the intensity of the ocular inflammatory processes, it is not clear yet whether these modes of treatment have any dramatic effect of the visual prognosis of the affected eyes. Despite intensive follow-up and treatment, loss of useful visual acuity has occurred in 74% of the eyes six to 10 years after the start of the ocular symptoms.
199 citations
TL;DR: Beta Ray applicators with 106Ru/106Rh can be recommended as an effective tool and a simple and cheap procedure to cure patients with small and medium sized choroidal melanomas and they save the eye without endangering patients' lives.
Abstract: From 1964 to 1984 309 patients with choroidal melanoma were treated with 106Ru/106Rh beta ray applicators (1000 Gy at the apex of the tumour within 7-14 days) In cases 216 (699%) this treatment was successful for a mean follow-up period of 67 years after irradiation In 53 cases (172%) the eye had to be enucleated, and 40 patients (129%) died from metastases within this period Of the 216 successfully treated patients 114 (528%) developed flat scars and 49 (227%) retained a visual acuity of 15-05 Radiogenic late complications with damage to the retinal capillary system were the main causes of visual deterioration, especially in eyes with tumours close to the posterior pole The survival rate is substantially higher than that for patients whose eyes were primarily enucleated beta Ray applicators with 106Ru/106Rh can be recommended as an effective tool and a simple and cheap procedure to cure patients with small and medium sized choroidal melanomas They save the eye without endangering our patients9 lives
190 citations
TL;DR: Analysis suggests that ablation induced by excimer laser results from highly localised photochemical reactions and that 193 nm is the optimal wavelength for surgery.
Abstract: This paper reviews the potential role of excimer lasers in corneal surgery. The morphology of incisions induced by two wavelengths of excimer laser radiation, 193 nm and 248 nm, are compared with the morphology of incisions produced by diamond and steel knives. Analysis suggests that ablation induced by excimer laser results from highly localised photochemical reactions and that 193 nm is the optimal wavelength for surgery. The only significant complication of laser surgery is loss of endothelial cells when incisions are within 40 micron of Descemet's membrane.
138 citations
TL;DR: In this series amblyopia, uncorrectable by spectacles and occlusion, was highly likely (48%) if a child had +3.50 or more dioptres of meridional hypermetropia at age 1 year, and squint as such was not so accurately predictable.
Abstract: In this series amblyopia, uncorrectable by spectacles and occlusion, was highly likely (48%) if a child had +3.50 or more dioptres of meridional hypermetropia at age 1 year. 45% of children with this refraction also had a squint. All those who remained with severely defective acuity in spite of treatment had either +3.50 or more dioptres of meridional hypermetropia or 4 or more dioptres of meridional myopia at age 1 year. These children were identifiable in the 3.7% of the population at age 1 year who showed high refractive errors. Squint as such was not so accurately predictable. Of those children with squint 71% had less than +3.50 dioptres of meridional hypermetropia at age 1 year--an incidence of 4.4% of the population. Apart from two 'congenital myopes' only 16% of these had residual amblyopia after treatment, and their last known acuity was never less than 6/12. Astigmatism in infancy or later is not significantly associated with squint or amblyopia.
126 citations
TL;DR: The pattern electroretinogram (PERG) was found to be normal in patients with microaneurysms and a few blot haemorrhages, however, when cotton-wool spots and angiographic evidence of areas of capillary non-perfusion were present, the PERG was reduced below the normal value.
Abstract: The pattern electroretinogram (PERG) and other tests were given to a selected group of patients with diabetes, ranging from those who had no retinopathy or funduscopic changes to those in the preproliferative state. None had visual symptoms. The PERG was found to be normal in patients with microaneurysms and a few blot haemorrhages. However, when cotton-wool spots and angiographic evidence of areas of capillary non-perfusion were present, the PERG was reduced below the normal value. Similar changes occurred with the oscillatory potentials of the ERG evoked by an intense flash, but the results were more variable. So in the individual patient the test is not a reliable indicator of the progress of the retinopathy. The value of the PERG in screening is discussed.
92 citations
TL;DR: The features and clinical significance of retinal macroaneurysm are described, systemic and local associations are noted, and guidelines for treatment by phototherapy are discussed.
Abstract: This report describes the features and clinical significance of retinal macroaneurysm. Two groups can be defined: those with acute aneurysmal decompensation, Group I; and those with chronic aneurysmal decompensation, Group II. Haemorrhage is the main feature of the former group and exudates of the latter. Systemic and local associations are noted, and guidelines for treatment by phototherapy are discussed.
89 citations
TL;DR: Light and electron microscopical changes in the retinal pigment epithelium following treatment with high dose desferrioxamine for systemic iron overload are documented, and Bruch's membrane overlying degenerate RPE cells appeared abnormally thickened.
Abstract: This study documents for the first time light and electron microscopical changes in the retinal pigment epithelium (RPE) following treatment with high dose desferrioxamine for systemic iron overload. The changes include loss of microvilli from the apical surface, patchy depigmentation, vacuolation of the cytoplasm, swelling and calcification of mitochondria, and disorganisation of the plasma membrane. In addition, Bruch9s membrane overlying degenerate RPE cells appeared abnormally thickened owing to the accumulation of large amounts of mature elastic fibres, pre-elastic oxytalan, and long spacing collagen. The specificity of these changes and the mechanism of toxicity are discussed.
81 citations
TL;DR: The quality of life of the surviving patients is good; none reported having a noticeable decrease in vision since 1969, and the mortality rate in patients with neurofibromatosis and those without neurof fibroma was essentially the same.
Abstract: We review the current status of 28 patients with chiasmal glioma who were originally reported on by Hoyt and Baghdassarian in 1969. The median period of follow-up was 20 years. Sixteen patients are now dead, five from chiasmal glioma and the rest from other causes. Four of the five deaths from chiasmal glioma occurred before 1969. The mortality rate in patients with neurofibromatosis and those without neurofibromatosis was essentially the same. Nine of 16 patients with neurofibromatosis are dead, two from chiasmal glioma, one from aspiration, and six from another tumour. Seven of 12 patients without neurofibromatosis are dead, three from chiasmal glioma, two from an operation on their tumour, and two from a medical illness. In general the quality of life of the surviving patients is good; none reported having a noticeable decrease in vision since 1969.
78 citations
TL;DR: It is considered that the conjunctiva of the dry eye, without the lacrimal secretion components of lysozyme and lactoferrin, has an alternative protective antibacterial mechanism which is derived from serum proteins via chronically inflamed vessels.
Abstract: The concentrations of tear lysozyme, lactoferrin, ceruloplasmin, IgA, and IgG have been estimated in patients with dry eyes at the same time as semiquantitative bacterial culture was performed of the conjunctivae and lids. Staphylococcal isolations were quantified and biotyped. There was no increased conjunctival colonisation by any particular biotype of Staphylococcus aureus or Staph. epidermidis, and similar numbers of conjunctivae were sterile as in controls (33%); neither were any pathogens such as pneumococci or haemophili isolated. We consider that the conjunctiva of the dry eye, without the lacrimal secretion components of lysozyme and lactoferrin, has an alternative protective antibacterial mechanism which is derived from serum proteins via chronically inflamed vessels.
76 citations
TL;DR: It was found that the tear film stability was significantly increased in eyes treated with sodium hyaluronate, and the symptoms of grittiness and burning were also significantly alleviated in the treated eyes.
Abstract: We evaluated the effect of 0.1% sodium hyaluronate (unpreserved) in 10 patients with dry eyes. The precorneal tear film break-up time was assessed by the non-invasive technique, and the severity of symptoms was recorded before and after treatment on a 0 to +3 scale. It was found that the tear film stability was significantly increased (p less than 0.05) in eyes treated with sodium hyaluronate. The symptoms of grittiness and burning were also significantly alleviated in the treated eyes.
TL;DR: One hundred and eighty-three surgical procedures were conducted on 107 patients over seven years and 91% of the cases of upper lid entropion were corrected satisfactorily with only one operation, postulated that this level of success is achieved by grading the degree of surgical intervention according to the clinical established on systematic examination ofupper lidEntropion.
Abstract: One hundred and eighty-three surgical procedures were conducted on 107 patients over seven years. 91% of the cases of upper lid entropion were corrected satisfactorily with only one operation. It is postulated that this level of success is achieved by grading the degree of surgical intervention according to the clinical established on systematic examination of upper lid entropion.
TL;DR: Retinal blood flow velocity was measured in 24 normal volunteers and compared with the results obtained in 101 diabetics at different stages of retinopathy, which showed that there was a significantly higher capillary flow velocity in those patients with background Retinopathy over the group of normals.
Abstract: Retinal blood flow velocity was measured in 24 normal volunteers and compared with the results obtained in 101 diabetics at different stages of retinopathy. The blue-light entoptic phenomenon was used to measure retinal flow velocity. Results showed that there was a significantly higher capillary flow velocity in those patients with background retinopathy (0.74 +/- 0.32 mms/s) over the group of normals (0.54 +/- 0.19 mm/s) and those diabetics with no retinopathy (0.51 +/- 0.24 mm/s). Retinal flow velocity was reduced at the preproliferative stage of retinopathy to 0.37 +/- 0.2 mm/s. Proliferative retinopathy showed a slightly greater flow velocity (0.56 +/- 0.27 mm/s), which was reduced following photocoagulation (0.42 +/- 0.14 mm/s).
TL;DR: It is concluded that an underlying lesion in ROP may be hypoxic ischaemic damage to the retinal circulation, and this condition was strongly associated with evidence of brain damage, often consistent with hypoxic Ischaemic injury.
Abstract: The eyes of 177 very preterm (less than 33 weeks' gestation) infants, born between 1979 and 1982 and admitted to a neonatal intensive care unit, were examined as part of an ongoing follow-up study of neurodevelopmental outcome. Ocular pathology was diagnosed in 37 (21%) of the 177 infants: 14 (8%) had retinopathy of prematurity (ROP)--progressive in three--and nine (5%) infants had delayed visual maturation (DVM). The ocular pathology was permanent in 26 (15%) of the 177 infants. Refractive errors were the commonest problem and accounted for permanent sequelae in eight of the 14 infants with ROP and two of the nine with DVM. The presence or absence of ROP was related to a wide range of prospectively coded perinatal variables and to the results of routine neonatal ultrasound brain scans and neurodevelopmental follow-up assessments made in the first 18 months of life. As in previous studies, infants with ROP were of shorter gestation, lower birth weight, and required oxygen therapy for longer than unaffected infants, but the condition was only weakly associated with other indices of respiratory illness. In contrast, ROP was strongly associated with evidence of brain damage, often consistent with hypoxic ischaemic injury. We conclude that an underlying lesion in ROP may be hypoxic ischaemic damage to the retinal circulation.
TL;DR: Six patients with abetalipoproteinaemia are described who received large doses of oral vitamin E for between 12 and 18 years in addition to a low fat diet and supplements of the other fat soluble vitamins.
Abstract: Six patients with abetalipoproteinaemia are described who received large doses of oral vitamin E for between 12 and 18 years in addition to a low fat diet and supplements of the other fat soluble vitamins. The progressive retinopathy observed in untreated abetalipoproteinaemia was substantially modified and most probably prevented by this therapy. Angioid streaks were noted in one patient. Treatment with vitamin A alone did not prevent or arrest the progression of the retinal lesion.
TL;DR: Comparison sensitivity testing appeared to be reduced whenever acuity was reduced, so that a distinction could be made between patients having a loss of contrast beyond the expectations for their level of acuity and those in whom a Loss of contrast simply corroborates the reduction of Acuity.
Abstract: A large group of individuals with retinal disease were tested prospectively for contrast sensitivity by means of Arden gratings. A subgroup of 19 were also tested with the Nicolet automated television system. Individuals with macular or peripheral dystrophy showed a general reduction in contrast sensitivity as visual acuity decreased. The loss of contrast sensitivity was more prominent for high spatial frequencies (6.4 cycles per degree) than for low ones (0.2 cycles per degree). Similar results were obtained for patients with achromatopsia and congenital stationary night blindness. Patients with functional complaints, but no organic basis for decreased acuity, showed greater scatter in their test scores. The Nicolet results showed somewhat smoother curves, but were no more specific in separating normality from abnormality. Contrast sensitivity testing was not specific for the retinal disease entities considered, but may be useful in recording a degree of retinal damage and a degree of functional visual disability. Contrast sensitivity appeared to be reduced whenever acuity was reduced, so that a distinction could be made between patients having a loss of contrast beyond the expectations for their level of acuity and those in whom a loss of contrast simply corroborates the reduction of acuity.
TL;DR: Oral administration of acyclovir (400 mg, five times daily) may be an effective alternative to topical therapy in selected patients with simple dendritic corneal ulceration.
Abstract: Sixty patients with simple dendritic corneal ulceration were randomly assigned to double blind treatment with either acyclovir tablets (400 mg) or acyclovir ophthalmic ointment administered five times daily. There was no significant difference in the proportions of patients healed in either treatment group (88.9% on oral acyclovir and 96.6% on acyclovir ointment). The median healing time was five days in both groups. No systemic or significant local side effects were noted in either treatment group. Trough levels of acyclovir in the tear fluid of those who received the oral preparation were within or above the range of mean in-vitro ID50 levels for herpes simplex virus type 1. We conclude that oral administration of acyclovir (400 mg, five times daily) may be an effective alternative to topical therapy in selected patients.
TL;DR: Twenty-three patients with bacterial keratitis had penetrating keratoplasties performed for deep indolent ulceration or descemetoceles, during the acute period, and eleven patients (48%) of those who had an acute graft achieved corrected visual acuities of 6/12 or better.
Abstract: Twenty-three patients with bacterial keratitis had penetrating keratoplasties performed for deep indolent ulceration or descemetoceles, during the acute period. The period in hospital (17.6 days) was significantly lower than for a control group (35.4 days) who were treated medically and had subsequent grafts. The number of grafts remaining clear was similar, 70% and 72% respectively. Eleven patients (48%) of those who had an acute graft achieved corrected visual acuities of 6/12 or better. No cases of reinfection occurred and no eyes were lost.
TL;DR: 1 Reinherz EL, Kung PC, Pesardo JM, Ritz J, Goldstein G, Schlossman SF, and Zola H. Ia determinants on human T-cell subsets defined by monoclonal antibody.
Abstract: 1 Reinherz EL, Kung PC, Pesardo JM, Ritz J, Goldstein G, Schlossman SF. Ia determinants on human T-cell subsets defined by monoclonal antibody. Activation stimuli required for expression. J Exp Med 1979; 150: 1472. 2 Schwartz BD, Paul WE, Shevach EM. Guinea pig la antigens: functional significance and chemical characterization. Transplant Rev. 1976; 30: 174. 3 Bodmer JG. Ia antigens. Definition of the HLA-/DRw specificities. Br Med Bull 1978; 34: 233. 4 Beckman IGR, Bradley J, Brooks D and Zola H. Debreation of sciologically distinct monomorphic determinants of human MHC class II antigens: evidence of heterogeneity in their topographical distribution. Mol Immunol 1984; 21: 205.
TL;DR: A range of morphological changes were observed by phase contrast microscopy, and these became more atypical with increasing concentration, indicating a relationship between cellular lytic activity and the capacity of the particle to degrade.
Abstract: Cultures of human retinal pigment epithelial cells have been challenged with a number of biological (lipofuscin, melanin, and rod outer segments) and non-biological (latex microspheres) particles at a variety of concentrations. The particles were chosen to include examples of both degradable and non-degradable systems. A range of morphological changes were observed by phase contrast microscopy, and these became more atypical with increasing concentration. At the highest concentration cells had ingested so many particles that many had died and others had ruptured. The time course of these changes indicated a relationship between cellular lytic activity and the capacity of the particle to degrade. The potential of this system as a model for studying senescence is discussed.
TL;DR: It is found that there is a considerable risk of sudden loss of visual field after operation on patients with primary open-angle glaucoma and small residual visual fields undergoing trabeculectomy.
Abstract: We studied the postoperative course of two groups of patients with primary open-angle glaucoma and small residual visual fields undergoing trabeculectomy. We found that there is a considerable risk of sudden loss of visual field after operation on these patients.
TL;DR: There is no evidence to support the suggestion that a widespread programme of vision screening at age 3 1/2 should be instituted, and some of the practical problems and defects of such a programme are outlined.
Abstract: There is no evidence to support the suggestion that a widespread programme of vision screening at age 3 1/2 should be instituted. Some of the practical problems and defects of such a programme are outlined. If the issues raised are to be resolved by further research, identification of preschoolchildren who have visual problems will be facilitated by a screening procedure involving refraction and possibly a cover test.
TL;DR: Three patients presented to us with disciform keratitis, peripheral corneal ring, and stromal infiltration following the topical use of oxybuprocaine, and all three patients developed marked decrease in vision secondary toCorneal scarring.
Abstract: Topically applied anaesthetics may lead to a serious keratopathy. Three patients presented to us with disciform keratitis, peripheral corneal ring, and stromal infiltration following the topical use of oxybuprocaine. All three patients developed marked decrease in vision secondary to corneal scarring. In all three patients oxybuprocaine was dispensed over the counter by a pharmacist. Legislation for the restriction of over-the-counter sale of topical anaesthetics, steroids, and antibiotics is essential in the prevention of many of the self-induced ocular disorders seen in developing countries.
TL;DR: The study shows that the definite diagnosis of ocular toxoplasmosis or its exclusion by serological means only is not yet feasible and the possible superiority of the ELISA test to the dye test warrants further investigation.
Abstract: The diagnostic value of toxoplasma serology in ocular disease was evaluated in the following groups of patients: (I) uveitis cases of various causes (n = 291); (II) consecutive posterior and panuveitis patients (n = 60); (III) patients with definite congenital and ocular toxoplasmosis (n = 8); (IV) cases of clinical ocular toxoplasmosis (n = 25); and control patients with uveitis of non-toxoplasma origin (n = 12). No relation was observed between the level of the dye test titres and the diagnosis of ocular toxoplasmosis (groups I and II). During the active stages of the disease no typical change of the titres occurred in several longitudinally studied patients with toxoplasmosis. In group III one case was discovered to be negative by the dye test despite active ocular disease; however, IgG antibodies against toxoplasma were detected by the ELISA technique. In group IV, which was investigated by the ELISA technique, 100% of the toxoplasmosis patients were positive for IgG versus 58% of the control patients. Circulating immune complexes containing IgG and toxoplasma antigen were detected in seven of 25 toxoplasmosis patients (28%) and in two of 12 control patients (16%). Our study shows that the definite diagnosis of ocular toxoplasmosis or its exclusion by serological means only is not yet feasible. The possible superiority of the ELISA test to the dye test warrants further investigation.
TL;DR: Squash, association football, badminton, and tennis were the main offenders, and the severest injury was from a golf ball, involving a fractured zygoma.
Abstract: To assess the prevalence of sports eye injuries in our area a register was kept over the 18 months from October 1982 to March 1984. Squash, association football, badminton, and tennis were the main offenders. The severest injury was from a golf ball, involving a fractured zygoma. There was one retinal dialysis, and one lens dislocation requiring extraction. Spectacles were broken in six cases and a contact lens in one. Glass fragments needed operative removal in one case, but there were no penetrating injuries. The value of eye protection, not worn by any of our patients, is emphasised.
TL;DR: periodic examinations by ophthalmoscopy and by functional tests such as EOG and visual fields should be continued in patients at risk of delayed-onset chloroquine retinopathy after discontinuance of the drug.
Abstract: Delayed-onset chloroquine retinopathy was diagnosed in a patient seven years after cessation of treatment by a total dose of 730 g of chloroquine for rheumatoid arthritis. Visual functions continued to deteriorate after the diagnosis. Periodic examinations by ophthalmoscopy and by functional tests such as EOG and visual fields should be continued in patients at risk of delayed-onset chloroquine retinopathy after discontinuance of the drug.
TL;DR: Preliminary results of the 34 degrees C and 4 degrees C closed Minnesota corneal preservation system using chondroitin sulphate show that it is safe and efficacious and allows intermediate to long-term maintenance of sterile thin tissue prior toCorneal transplantation.
Abstract: The clinical and laboratory results with a modified Minnesota system of organ culture corneal preservation are presented. A refinement of our preservation technique using a closed system, as well as the addition of chondroitin sulphate to the medium is presented. Laboratory results show preservation of corneal endothelial integrity for at least 21 days with maintenance of normal corneal thickness. In addition, a 10-day quarantine system reduces the risk of donor contamination and secondary endophthalmitis. Preliminary results of the 34 degrees C and 4 degrees C closed Minnesota corneal preservation system using chondroitin sulphate show that it is safe and efficacious and allows intermediate to long-term maintenance of sterile thin tissue prior to corneal transplantation.
TL;DR: It is concluded that in experienced hands the Dunlop test is a useful indicator of the development of vergence control and that immaturity ofVergence control may contribute to children's reading problems.
Abstract: Using the Dunlop synoptophore test we have examined the reliability of vergence control for small fusion targets in 753 primary school children aged 7-11, and we have compared these results with the reading performance of 451 of them. 30% of the total sample of children had unstable responses in the Dunlop test. The proportion decreased with age, ranging from 49% of 5-year-olds to only 11% of 10-year-olds. The reading of children who had developed accurate vergence control was on average 6.3 months in advance of those who had not. Those with unstable Dunlop test responses were much more likely to be backward or low normal readers than children with stable responses. We conclude that in experienced hands the Dunlop test is a useful indicator of the development of vergence control and that immaturity of vergence control may contribute to children's reading problems.
TL;DR: A cross sectional, prevalence survey of eye disease in the population over 75 years old of Melton Mowbray has been used to examine the accuracy and completeness of the Blind and Partially Sighted Registers.
Abstract: A cross sectional, prevalence survey of eye disease in the population over 75 years old of Melton Mowbray has been used to examine the accuracy and completeness of the Blind and Partially Sighted Registers. The Blind Register had high sensitivity and specificity but was found to underestimate the prevalence of blindness by a factor of 1.1. The Partially Sighted Register had high specificity, but the sensitivity was only 50% and it underestimated the prevalence of partial sight by a factor of 1.5. Seven persons eligible for registration, but previously not registered, were found, two as blind and five as partially sighted. This represented 21% of the registrable visually impaired population.