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High Myopia (high + myopia)
Selected AbstractsHigh myopia, hypertelorism, iris coloboma, exomphalos, absent corpus callosum, and sensorineural deafness: Report of a case and further evidence for autosomal recessive inheritanceACTA OPHTHALMOLOGICA, Issue 2 2000Avni Murat Avunduk No abstract is available for this article. [source] Knobloch syndrome: Novel mutations in COL18A1, evidence for genetic heterogeneity, and a functionally impaired polymorphism in endostatin,HUMAN MUTATION, Issue 1 2004Olivier Menzel Abstract Knobloch syndrome (KNO) is an autosomal recessive disorder characterized by high myopia, vitreoretinal degeneration with retinal detachment, and congenital encephalocele. Pathogenic mutations in the COL18A1 gene on 21q22.3 were recently identified in KNO families. Analysis of two unrelated KNO families from Hungary and New Zealand allowed us to confirm the involvement of COL18A1 in the pathogenesis of KNO and to demonstrate the existence of genetic heterogeneity. Two COL18A1 mutations were identified in the Hungarian family: a 1-bp insertion causing a frameshift and a premature in-frame stop codon and an amino acid substitution. This missense variant is located in a conserved amino acid of endostatin, a cleavage product of the carboxy-terminal domain of collagen alpha 1 XVIII. D1437N (D104N in endostatin) likely represents a pathogenic mutation, as we show that the endostatin N104 mutant is impaired in its affinity towards laminin. Linkage to the COL18A1 locus was excluded in the New Zealand family, providing evidence for the existence of a second KNO locus. We named the second unmapped locus for Knobloch syndrome KNO2. Mutation analysis excluded COL15A1, a member of the multiplexin collagen subfamily similar to COL18A1, as being responsible for KNO2. Hum Mutat 23:77,84, 2004. © 2003 Wiley-Liss, Inc. [source] A novel genetic variant of BMP2K contributes to high myopiaJOURNAL OF CLINICAL LABORATORY ANALYSIS, Issue 6 2009Hsin-Ping Liu Abstract Loss of eye growth regulation may cause myopia, because modulation of optic globe size is essential for the generation of normal optic power. Evidence has implied variations of BMP2 gene expression mediate ocular development and retinal tissue remodeling. Given BMP2 as a potential regulator involved in myopia development, we investigate whether gene BMP2-inducible kinase (BMP2K, BIKe), whose expression is up-regulated during BMP2-induced osteoblast differentiation, contributes to susceptibility of high myopia. Participants grouped into high myopia had a spherical equivalent greater than ,6.00 D, compared with a control group of spherical equivalent less than ,0.5 D. Genotyping of polymorphisms 1379 G/A (rs2288255) and 3171 C/G (rs12507099), corresponding with 405 Gly/Ser and 1002 Thr/Ser variation in the BMP2K gene were determined by PCR-restriction fragment length polymorphism and associative study performed by comparing high myopic subjects and healthy controls. The frequency of A allele in the BMP2K gene 1379 G/A polymorphism showed a significant difference between cases and controls (P<0.001, OR=2.99, 95% CI=1.62,5.54) and subjects with either AA or AG genotype show higher risk than GG genotype (P<0.001, OR=3.07, 95% CI=1.59,5.92), while 3171 C/G polymorphism was not significant from this survey. These data suggest that BMP2K gene 1379 G/A variant is strongly correlated with high myopia and may contribute to a genetic risk factor for high degrees of myopic pathogenesis. J. Clin. Lab. Anal. 23:362,367, 2009. © 2009 Wiley-Liss, Inc. [source] A review of Donnai-Barrow and facio-oculo-acoustico-renal (DB/FOAR) syndrome: Clinical features and differential diagnosisBIRTH DEFECTS RESEARCH, Issue 1 2009Barbara R. Pober Abstract Mutations in the gene LRP2 have recently been identified as the cause of Donnai-Barrow and Facio-oculo-acoustico-renal (DB/FOAR) syndrome. More than two dozen cases, the first reported more than 30 years ago by Holmes, have been published. Summarizing available information, we highlight the cardinal features of the disorder found in ,90% of published cases. These features include: agenesis of the corpus callosum, developmental delay, enlarged anterior fontanelle, high myopia, hypertelorism, proteinuria, and sensorineural hearing loss. Congenital diaphragmatic hernia and omphalocele are reported in only half of the patients. There is no evidence for genotype-phenotype correlation, though the sample size is too small to preclude this with certainty. Although several conditions to consider in the differential diagnosis are highlighted, the diagnosis of DB/FOAR syndrome should not be difficult to establish as its constellation of findings is strikingly characteristic. Birth Defects Research (Part A), 2009. © 2008 Wiley-Liss, Inc. [source] Lens opacity and refractive influences on the measurement of retinal vascular fractal dimensionACTA OPHTHALMOLOGICA, Issue 6 2010Haitao Li Acta Ophthalmol. 2010: 88: e234,e240 Abstract. Purpose:, To examine the influence of lens opacity and refraction on the measurement of retinal vascular fractal dimension (Df). Methods:, Optic disc photographs (right eyes) of 3654 baseline Blue Mountains Eye Study participants (aged 49,97 ) were digitized. Retinal vascular Df was quantified using a computer-based program. Summated severity scores for nuclear, cortical and posterior subcapsular (PSC) cataract were assessed from lens photographs. Refraction data were converted to spherical equivalent refraction (SER), as sum spherical plus 0.5 cylinder power. Axial length was measured at 10-year follow-up examinations using an IOL master. Results:, Mean Df of the retinal vasculature was 1.444 ± 0.023 for 2859 eligible participants. Increasing lens opacity scores were associated with significant reduction in Df (, = ,0.0030, p < 0.0001). Both cortical and PSC cataract involving central lens area were associated with reduced Df, after controlling for confounding factors (ptrend , 0.0105). Increasing myopia severity was associated with reduced Df after adjusting for lens opacity scores and other confounders (ptrend < 0.0001). The slope of Df decrease per SER reduction was 0.0040 in eyes with SER , ,4D, compared to ,0.0016 in eyes with SER > ,4D. For axial length quintiles, there were no significant differences in mean Df in all groups except a reduction in the fifth quintile (axial length ,24.15 mm) (all p < 0.05). Conclusion:, Ocular media opacity independently influenced retinal vascular Df measurement, but we found no evidence supporting any refractive axial magnification effect on this measure. Myopic refraction ,,4D was associated with a reduction in Df, suggesting rarefaction of retinal vasculature associated with high myopia. [source] Optic disc appearance and retinal temporal vessel arcade geometry in high myopia, as based on follow-up data over 38 yearsACTA OPHTHALMOLOGICA, Issue 5 2010Hans C. Fledelius Abstract. Purpose:, To discuss (i) optic disc appearance and (ii) the retinal course of the temporal vessel arcade in a longitudinal series of high myopia patients followed between the ages of 16 and 54. Methods:, Thirty-nine individuals from a 1948 Copenhagen birth cohort (n = 9243) who had myopia of ,6 to ,15 D when aged 14 years were invited for current follow-up exams with 7,10-year intervals. Fundus photos were available from up to five occasions over 38 years, and single eye photo collages were studied with respect to posterior pole changes over time. Results:, Fifty-two eyes with high myopia were available. (i) Contrary to the expected predominance of large flat optic discs in long eyes, more than half the eyes in the sample had neurodiscs that were perceived to be small; many were also oval/kinked/tilted and with minimum or absent physiological cups. Among the fellow eyes with unilateral high myopia only one out of the 10 discs appeared as small/tilted. (ii) By age, a more acute angle between upper and lower temporal retinal vessel trunks was found in 12/20 eyes with adult myopia progression (change over time 5,23°) and in 6/24 eyes with stable myopia. In the myopia-progression subgroup, peaking of the angle was correlated with myopia degree, myopia increase and axial elongation. Conclusion:, Contrary to clinical expectation, we found neurodiscs that appeared to be small and dense in eyes with high myopia. We further discussed the eventual peaking of the angle between the temporal vessel arcades that is sometimes observed in high myopia. Occasionally, literature on myopia reports the presence of small and tilted discs whereas no mention was found of the issue of temporal vessel arcade peaking. [source] Eye shape and peripheral visual field recording in high myopia at approximately 54 years of age, as based on ultrasonography and Goldmann kinetic perimetryACTA OPHTHALMOLOGICA, Issue 5 2010Hans C. Fledelius Abstract. Purpose:, This study describes the posterior pole contour and visual field (VF) findings in an unselected series of adults (aged approximately 54 years) with high myopia. Methods:, In 1962, 39 14-year-old teenagers with myopia of , 6 D, in one or both eyes, were identified in a 1948 Copenhagen birth cohort (n = 9243). At a follow-up in 2002, 61 eyes (52 with high myopia and nine fellow eyes; n = 31 subjects) were examined by ultrasound B-scan, to allow: (a) measurement of the axial vitreous length supplementary to the customary axial A-scan, and (b) assessment of the posterior pole contour of the eye. Further, the large-object (V, 4e) kinetic Goldmann perimetry isoptre was recorded to outline the ambulatory VF. Results:, An irregular posterior pole contour was observed in 15 eyes, unilaterally in 11 eyes and bilaterally in four (two subjects). Nasal fundus ectasia was suggested in six and other deviations from the sphere in seven subjects. Kinetic Goldmann perimetry showed marginal restriction in 14 eyes (12 subjects). Larger defects were found in four eyes (three subjects); the corresponding axial lengths exceeded 32 mm in the two subjects with unilateral defects, and symmetrical inferior binasal defects, probably unrelated to the myopia, were found in the bilateral subject. Conclusions:, Unselected adult-age high myopia mainly presented with a regular eye shape that was close to spherical. An irregular shape suggesting posterior staphyloma was seen in 13 of the 32 subjects under study, mainly unilaterally. No subjects were restricted in everyday activities by VF defects. Marginal Goldmann perimetry restrictions were described in 12 and significant defects in three subjects. Generally, longer eyes more often tended to show irregular posterior eye contours and/or VF defects. [source] Oculometry findings in high myopia at adult age: considerations based on oculometric follow-up data over 28 years in a cohort-based Danish high-myopia seriesACTA OPHTHALMOLOGICA, Issue 4 2010Hans C. Fledelius Abstract. Purpose:, To present and discuss oculometry data in a series of adults with high myopia followed between the ages of 26 and 54 years. Emphasis is on axial length (AL) findings and corneal curvature radius (Crad). Methods:, Thirty-four out of the 39 individuals recruited as teenagers from a Copenhagen 1948 birth cohort with myopia of at least 6 D have had current follow-up exams, to include AL measurements (by ultrasound, 1974,2002; the latter year also with the Zeiss IOLMaster) and keratometry. The cross-sectional and longitudinal analyses are based primarily on the eyes with high myopia; however, the fellow eye is also assessed in unilateral cases. Results:, At age 54 years, the maximum myopia in the series was ,26 D; the highest AL value was 35.4 mm. The myopia had increased in most, with an increase from the 26-year oculometry baseline averaging 1.0 D [standard deviation (SD) 1.84]. Ultrasound measurements over the 28 years gave a significant correlation between axial eye elongation and myopia progression of adult age (r = 0.65). The regression line was y = 0.43 + 0.36x, with myopia increase on the x-axis. Throughout sessions, the association between AL and refraction was given by correlation coefficients numerically above 0.8, whereas AL and Crad had r -values of 0.3,0.5. However, a mean Crad in the sample of 7.66 (SD 0.28) mm meant that the more general expectancy of rather flat corneas in high myopia was not fulfilled. Our data further suggested a reduction in lens power over the study period. Conclusion:, In relation to refraction, AL and Crad remain the two main oculometry parameters. Apparently the correlation patterns regarding the cornea that are broadly valid for axial ametropia in the population cannot be extended to the marginal high myopia tail of the distribution. A significant proportion of eyes with high myopia thus had steeper corneas than expected, as a so-called index contribution (albeit a small one) to the marginal refractive error. [source] Retinal detachment in phakic patientsACTA OPHTHALMOLOGICA, Issue 2009C CHIQUET Purpose this review aims to summarize risk factors, preoperative evaluation and principles of operative methods of retinal detachment of phakic eyes Methods Preoperative evaluation includes detailed examination of the retina, the identification of retinal breaks and classification of proliferative retinopathy. Main operative methods will be presented with ab externo or ab interno techniques. Results after a detailed characterization of the retinal detachment, the more appropriate surgical methods will be explained for the search, the treatment (laser or cryotherapy), closure (scleral buckling materials) of retinal breaks, management of subretinal fluid (drainage) and the choice of the intraocular tamponnade (gas or silicone). Conclusion this review will discuss the main advantages of each surgical technique and examples of management will be presented (simple phakic detachment, associated cataract, giant tears, high myopia). [source] Comparison of two partial coherence interferometers for corneal pachymetry in high myopia and after LASIKACTA OPHTHALMOLOGICA, Issue 4 2009Anders Ivarsen Abstract. Purpose:, We aimed to compare the Haag-Streit optical low-coherence reflectometry (OLCR) pachymeter and the Zeiss Anterior Chamber Master (ACMaster) for measuring central corneal thickness (CCT) in high myopes and after laser in situ keratomileusis (LASIK) for myopia. Methods:, Central corneal thickness was measured in 55 eyes of 30 myopic subjects (spherical equivalent refraction of , 5.25 D to , 10.75 D, maximal astigmatism of , 2 D), and in 37 eyes of 21 patients 3 months after LASIK for myopia (preoperative spherical equivalent refraction of , 6.0 D to , 10.75 D, maximal astigmatism of , 2 D). All measurements were performed with the Haag-Streit OLCR pachymeter and the Zeiss ACMaster, using group refractive indices of 1.376 and 1.3851, respectively. Thickness measurements were compared using paired t -tests, Pearson's correlation, linear regression and Bland,Altman plots. Results:, In myopic subjects, CCT measured 531 ± 28 ,m and 533 ± 27 ,m with the OLCR pachymeter and the ACMaster, respectively (p < 0.01); all measurements correlated closely (r = 0.99, p < 0.01). In LASIK-treated eyes, CCT measured 472 ± 24 ,m using the OLCR pachymeter and 475 ± 23 ,m using the ACMaster (p < 0.01), again with close correlation between the two instruments (r = 0.99, p < 0.01). Conclusions:, Measurements of CCT in high myopes and after myopic LASIK were very similar with the Haag-Streit OLCR pachymeter and the Zeiss ACMaster. Using the current group refractive indices, the observed difference between the two instruments of < 3 ,m is of little clinical importance. Thus, it would seem safe to use the OLCR pachymeter and the ACMaster interchangeably for CCT measurements in myopia as well as after myopic LASIK. [source] Computer-assisted dosage calculation for strabismus therapy in myopic patientsACTA OPHTHALMOLOGICA, Issue 1 2008Martina Koch Abstract. Purpose:, The published dosage recommendations for the surgical correction of horizontal strabismus in non-myopic patients show large, unexplained differences. For patients with high myopia, the situation becomes even more complex because the increase in the size of the bulb also affects the geometry of the oculomotor muscles. In this study, we wanted to investigate whether computer simulations of the oculomotor plant can be used to find accurate surgical parameters. Methods:, In a retrospective study, we investigated pre- and postoperative strabismus patterns in 13 patients affected by convergent (seven patients) or divergent (six patients) strabismus and high myopia. Postoperative checks were made 1 day, 1 week, 3 months and 1,6 years after the operation. For each patient, we simulated the presurgical strabismus pattern with SEE++ (see ,Further Information' for manufacturer details), a biomechanical simulation program of the oculomotor plant. The individual results of the simulations were then compared to the measured postoperative strabismus patterns. Results:, We found a trend of under-correction in the postoperative situation, resulting in four patients having a large remaining strabismus angle of more than 5 degrees. The computer simulations were able to reproduce this under-correction, and suggested an increase in dosage. Conclusion:, We conclude that realistic biomechanical simulations of the oculomotor plant can predict the postoperative result for myopic patients accurately. The results of the computer simulation correlate well with the postoperative outcome of the patient. [source] Comparison of visual acuity measurements and Purkinje's vessel shadow perception for prediction of postoperative visual acuity in different ophthalmological diseasesACTA OPHTHALMOLOGICA, Issue 2 2007Stephan Schulze Abstract. Purpose:, Prediction of postoperative visual acuity (VA) is extremely important to the patient and highly relevant to the surgeon. However, objective evaluation of the macula is frequently impossible in cases such as mature cataract, cataract in high myopia or vitreous haemorrhage. This study compares different preoperative examination techniques used to predict postoperative VA. Methods:, We retrospectively evaluated the charts of all patients who underwent any of the following procedures at our hospital in 2004: phacoemulsification for mature cataract or cataract in high myopia; vitrectomy for diabetic vitreous haemorrhage; macular pucker, and macular hole. The following methods were evaluated: preoperative distance and reading VA; laser interferential VA; Purkinje's vessel shadow perception, and postoperative distance VA. Results:, Complete documentation was available for 136 patients (29 mature cataracts, 25 immature cataracts in high myopia, 42 vitreous haemorrhages, 19 macular puckers, 21 macular holes). In cases of preoperative mature cataract, a positive Purkinje's vessel shadow perception predicted a postoperative VA , 20/50 (odds ratio 11.2). In cases of high myopia, interferential VA correlated best with visual outcome (p < 0.05). In macular surgery laser interferential VA predicted postoperative VA to be better and preoperative reading VA predicted it to be worse than it actually turned out after surgery. Laser interferential VA and last known VA prior to vitreous haemorrhage (mean of 20 months previously) correlated best with postoperative VA (p < 0.05) in cases of vitreous haemorrhage. Purkinje's vessel shadow perception , if positive , predicted a postoperative VA , 20/300 in these cases (odds ratio 15.0). Conclusions:, Postoperative VA after vitrectomy for macular pucker or macular hole and in cases of cataract in high myopia is best predicted by laser interferential VA. Postoperative VA after vitrectomy for diabetic vitreous haemorrhage is best predicted by prehaemorrhage VA or laser interferential VA, especially when prehaemorrhage VA is unknown. Positive Purkinje's vessel shadow perception is an excellent method of predicting postoperative VA , 20/300 in cases of vitreous haemorrhage and VA = 20/50 in mature cataract. [source] The key role of electrophysiology in the diagnosis of visually impaired childrenACTA OPHTHALMOLOGICA, Issue 6 2006Maria Van Genderen Abstract. Purpose:, To describe the outcome of specialized electrophysiology in visually impaired children. Methods:, We carried out a retrospective evaluation of 340 electrophysiological examinations performed in 298 children over a 3-year period (2001,2003), with regard to demographic data, referral pattern, degree of compliance, and diagnostic results. Electrophysiology was performed without sedation or anaesthesia. In electroretinograms, DTL electrodes were used in combination with online selection of responses. Visual evoked potentials testing was performed with seven active occipital electrodes. Results:, The mean age of the children was 7 ± 5 years; 72 (24%) of the children were mentally as well as visually impaired. Main reasons for referral were suspected posterior segment disease, abnormal visual development, unexplained low vision, high myopia, and suspected albinism. Compliance was good in 302/340 (88%), partial in 24/340 (7%), and absent in 14/340 (4%) of the examinations. Of the 326 successful procedures, 215 (66%) showed abnormal results. Tapetoretinal dystrophy (22%), opticopathy (16%), congenital stationary night blindness (13%), and cone dystrophy (11%) were the most frequently established diagnoses. Albinism was confirmed in 14 of 24 suspected patients; additionally, unsuspected misrouting was found in six. In 26 (9%) of the patients, a previously established diagnosis was changed. Conclusions:, In a specialized setting, electrophysiological examinations can be performed successfully in visually impaired children. The results are essential for the final ophthalmological diagnosis and have important consequences for rehabilitation. [source] Myopisation: The refractive tendency in teenagers.ACTA OPHTHALMOLOGICA, Issue 2 2000Prevalence of myopia among young teenagers in Sweden ABSTRACT. Purpose: 1045 children between 12 and 13 years old were examined in a field study in the Göteborg area (Sweden). The aim of this study was to report the prevalence of refractive errors, with special attention to myopia, since there are no previous reports in Sweden about this age group. Methods: The examination included visual acuity testing and refraction under cycloplegia. Results: We found a prevalence of myopia (,,0.5D) of 49.7% and a prevalence of bilateral myopia of 39%. In the whole population, 23.3% were considered to need glasses (,,0.75D). We also found a prevalence of high myopia (,,5D) in 2.5% of the children. Discussion: No statistically significant difference in myopia with respect to gender was found. The proportion of children needing glasses is considered the best indicator of the prevalence of myopia in this sample. The results confirm that this tendency towards myopisation in a teenage population in Göteborg is similar to the prevalence found in other parts of the world. [source] Subthreshold transpupillary thermotherapy in Chinese patients with myopic choroidal neovascularization: one- and two-year follow upCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 5 2008Pei-Chang Wu MD Abstract Background:, To perform a safety and efficacy study of subthreshold transpupillary thermotherapy (TTT) in Chinese patients with choroidal neovascularization (CNV) secondary to pathologic myopia. Methods:, In a prospective study, patients with subfoveal or juxtafoveal CNV secondary to high myopia underwent subthrehold TTT with fixed treatment and follow-up protocols. From October 2002 to July 2005, 12 and 24 months of follow up were completed for 21 eyes and 13 eyes respectively. Results:, The mean best-corrected visual acuities (BCVA) were maintained at the baseline level at 1 and 2 years. Seventy-two per cent of eyes and 63% of eyes had stable or improved BCVA at 12 and 24 months. Thirty-four per cent and 39% of eyes had a moderate gain in vision (improved by three or more lines) at 12 and 24 months respectively. The average number of subthreshold TTT treatments was 1.7. The major complication of subthreshold TTT included laser-related low-grade retinal pigment epithelium atrophy in two eyes of young patients with clear lenses. The final VA was significantly associated with pretreated VA (r = 0.614, P = 0.003). The final VA improvement was significantly associated with pretreatment VA in negative correlation (r = ,0.731, P = 0.0002, Person correlation test). Conclusions:, Subthreshold TTT in Chinese patients with pathologic myopia and subfoveal or juxtafoveal CNV generally maintained vision at 1- and 2-year follow up. Using decreased power of subthreshold TTT, especially in the younger patients with a clear lens, is suggested. [source] Marked discordance for myopia in female monozygotic twinsCLINICAL & EXPERIMENTAL OPHTHALMOLOGY, Issue 3 2006Mohamed Dirani BOrth & OphthSc(Hons) Abstract Female monozygotic twins aged 54 years discordant for myopia are reported. One twin presented with bilateral high myopia (right eye = ,6.00/+0.50 × 5°, left eye = ,6.00/+0.50 × 45°) and her identical twin had no significant refractive error (right eye = ,0.50/plano, left eye = ,0.50/+0.75 × 40°). An explanation for the striking refractive discordance seen in this case report is yet to be determined. [source] | |||||||||||||