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Purpose: Accurate refraction is arguably the most important parameter for a successful laser vision correction surgery and is based on a combination of manifest and cycloplegic refraction. Wavefront?based objective refraction may be useful in the evaluation of patients. So far, the reliability of objective refraction as measured using the Pentacam® AXL Wave has not been published in the literature. Methods: This was a prospective study including a total of 168 eyes belonging to 84 young non?presbyopic patients evaluated for refractive surgery. Pentacam® AXL Wave full sequence was taken for all patients. Then, a clinician who was unaware of the objective refraction results performed a full physical examination, including manifest refraction starting from an autorefractometer value. All refraction values were transferred to astigmatic power vectors as per the Thibos method. Reliability of the different vectors and a unifying blur value were compared using Spearman correlation, Bland–Altman plot, and intraclass correlation coefficient. Results: The mean age was 28.8 ± 5.4 years, with a female preponderance (60.7%). The correlation between both eyes was high. The difference in M vector between subjective and objective refraction was 0.16 D, while the difference was 0.04 and 0.01 D for the J0 and J45 vectors, respectively. Paired samples Student t was non?significant for all comparisons. Spearman rho correlations were high (0.666–0.924, all P < 0.001). Intraclass correlation coefficients were also high (0.890–0.966). Bland–Altman plots did not demonstrate any systematic errors. Conclusion: Wavefront?based refractive refraction obtained using the Pentacam® AXL Wave is highly agreeable and correlated with measurements obtained by manifest subjective refraction.
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Abstract Purpose: To evaluate six different premium IOLs retrospectively in respect to both subjective and objective refraction after cataract operation. Methods: Five hundreds and seventy eyes of 285 patients with bilateral cataract who had undergone phacoemulsification and IOL implantation operation between February 2017 and September 2018 were enrolled in this study. The mean age of the patients was 57.78 ± 7.49 (41-71) years. Out of 285 patients 137 were male (48.07%) and 148 were female (51.93%). TheIOLsusedare: RayOne Trifocal (Rayner, Worthing, UK), Lucidis (Swiss Advanced Vision, Neuchâtel, Switzerland), PanOptix (Alcon, Fort Worth, USA), LentisMplus (Oculentis, Berlin, Germany), TecnisSymfony (Abbott, Illinois, USA) and Acriva Trinova (VSY Biotechnology, Istanbul, Turkey). Results: There were no significant differences among the groups regarding age, sex, axial length, the mean preoperative and postoperative uncorrected visual acuity (UCVA), best-corrected visual acuity (BCVA), the mean preoperative spherical equivalent (SE) and the mean postoperative SE (subjective measurement) (P> .05). The postoperative refractions measured with autorefractometer were more myopic than subjective refractions in all patients except the patients who had PanOptix IOL. In postoperative twelfth month, the mean UCVA arrived 0.00 logMAR in 405 eyes (78.48%) , however, the mean autorefractometric measurement was -1.28 ± 1.02 (0.00_-2.75) D. Conclusion: The autorefractometer measurements of all patients who had premium IOLs except PanOptix IOL were not coherent with their visual acuities postoperatively. The ophthalmologists and/or optometrists should be careful while examining these types of patients.
Resumo Objetivo: Avaliar retrospectivamente seis diferentes LIOs premium em relação à refração subjetiva e objetiva após operação de catarata. Métodos: Quinhentos e setenta (570) olhos de 285 pacientes com catarata bilateral submetidos a facoemulsificação e operação de implantação de LIO entre fevereiro de 2017 e setembro de 2018 foram incluídos neste estudo. A média de idade dos pacientes foi de 57,78 ± 7,49 (41-71) anos. Dos 285 pacientes, 137 eram do sexo masculino (48,07%) e 148, do sexo feminino (51,93%). As seguintes IOLs foram utilizadas: RayOne Trifocal (Rayner, Worthing, Reino Unido), Lucidis (Swiss Advanced Vision, Neuchâtel, Suíça), PanOptix (Alcon, Fort Worth, EUA), LentisMplus (Oculentis, Berlim, Alemanha), TecnisSymfony (Abbott, Illinois, EUA) e Acriva Trinova (VSY Biotechnology, Istambul, Turquia). Resultados: Não houve diferenças significativas entre os grupos em relação à idade, sexo, comprimento axial, média da acuidade visual não corrigida pré e pós-operatória (AVNC), melhor acuidade visual corrigida (MAVC), equivalente esférico pré-operatório médio (EE) e EE pós-operatório médio (medição subjetiva) (P > 0,05). As refrações pós-operatórias medidas com autorefratômetro foram mais míopes do que as refrações subjetivas em todos os pacientes, exceto naqueles que usavam LIO PanOptix. No décimo segundo mês pós-operatório, a AVNC média chegou a 0,00 logMAR em 405 olhos (78,48%); no entanto, a medição autorefractométrica média foi de -1,28 ± 1,02 (0,00_-2,75) D. Conclusão: As medições autorefractométricas de todos os pacientes que usavam LIOs premium, exceto LIO PanOptix, não foram coerentes com suas acuidades visuais no pós-operatório. Oftalmologistas e/ou optometristas devem ter cuidado ao examinar pacientes com esses perfis.
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Humans , Male , Female , Adult , Middle Aged , Aged , Refraction, Ocular , Visual Acuity , Phacoemulsification/methods , Lenses, Intraocular , Retrospective StudiesABSTRACT
@#AIM: To evaluate the effect of red-green duochrome test in subjective refraction.<p>METHODS: A randomly-selected sample size of 60 new patients with myopia were measured twice using subjective refraction with and without the red-green duochrome test. Assessments on the effectiveness were made based on comprehensive optometry analysis, accommodation response, accommodation sensitivity, positive and negative relative accommodation.<p>RESULTS: Application of red-green duochrome test on the targeted population did not show any statistical significance to the subjective refraction results. No difference was observed on patients with dilated pupils(<i>P</i>=0.686)and non-dilated pupils(<i>P</i>=0.655). Bland-Altman analysis of displayed good consistency between both subjective refraction measurements on each patient. Multivariate linear regression analysis shows that the results of subjective refraction were independent of age, obliquity, regulation lag, positive relative adjustment, and negative relative adjustment effect(<i>P</i>>0.05).<p>CONCLUSION: The red-green duochrome test does not affect optometric results.
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Objective To compare subjective refraction based on power vectors and conventional subjective refraction in different degrees of astigmatism.Methods A total of 143 subjects (143 right eyes) were divided into two groups according to astigmatism degree:low astigmatism group (0-1.50 D) and high astigmatism group (1.50 -3.00 D).Subjects were then examined by both methods to fetch refraction data,and then the equivalent spherical M component,J0 component,J45 component and the duration of refraction procedures were compared and analyzed.Results There was no statistically difference in age,gender,M component,J45 component and time consuming of subjective refraction between the high and low astigmatism groups (all P ＞ 0.05),but intergroup comparison of J0 component from subjective refraction based on power vectors and conventional subjective refraction was significantly different (all P =0.00).In the low astigmatism group,the agreement of M,J0 and J45 measured by the two methods was tmified,and the mean absolute value of M,J0 and J45 difference was 0.04 D,0.02 D and 0.02 D,respectively;moreover,within the limits of consistency,the maximum absolute value of the difference was 0.37 D,0.13 D and 0.17 D,respectively,and there was no statistically difference in time consuming of the two methods (P =0.72).In the high astigmatism group,the agreement of M,J0 and J45 measured by the two methods was poor,and the mean absolute value of M,J0 and J45 difference was 0.43 D,0.21 D and 0.00 D,respectively;moreover,within the limits of consistency,the maximum absolute value of the difference was 0.75 D,0.50 D and 0.30 D,respectively,and the difference in time consuming of the two methods approached statistical significance (P =0.00),suggesting time consuming of subjective refraction based on power vectors was longer.Conclusion Subjective refraction based on power vectors has good effect on low astigmatism,and it needs to be further improved for clinical practices.
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Introduction: Refractive error is the most common visual impairment seen worldwide. This is one of the main cause for which patients come to ophthalmologist. This can occur at any age of the patient. Automated refractometer has become popularised method for doing refraction because of the busy practise of ophthalmologist and due to heavy patients load in screening camps. It is an easy method to learn, to operate and also time saving procedure. Patients are also very comfortable with it because of this easy procedure done in short time. But Streak retinoscopy which is considered as a Gold standard technique for refraction, has some difficulties like time consuming, dilatation of pupil and discomfort to the patient. Aim: Comparing the effect of the conventional method of refraction with computerized automated refraction in various refractive error patients. Materials and methods: It was an observational, cross-sectional study done in a 50 refractive error patients who attend Department of Ophthalmology OPD. Results: According to the statistical analysis done to compare the refraction values of the auto refractometer and streak retinoscopy with the patient's acceptance value, results came as streak Deepikadevi SN, Sundararajan D, Namitha Bhuvaneshwari K, Murali Krishnan. Comparing the effect of conventional method of retinoscopic refraction with computerized automated refraction in various refractive error patients. IAIM, 2017; 4(10): 105-110. Page 106 retinoscopy values had no significant difference with the patient's acceptance value. This study also shows males were more affected by refractive errors than females and the mean age of affection in myopia was 19- 20 years and hypermetropia is 33-36 years. Conclusion: Since reteak retinoscopy values are accepted well by the patients, it is the better method for refrection than auto refractometer
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AIM:To compare the refractive errors measured by the VISX WaveScan, OPD - Scan Ⅲ and the subjective refraction. METHODS: Seventy - six patients ( 152 eyes ) were recruited from January 2013 to December 2013. All patients were measured with subjective refraction by the phoropter (NIDEK, RT-5100), objective refraction by the WaveScan ( AMO Company, USA) , OPD-ScanⅢ ( Nidek Technologies, Japan). The sphere, cylinder, axis of the three methods were compared and analyzed. RESULTS: The sphere measured by WaveScan was lower than that by subjective refraction, the difference was 0. 13±0. 30D (t=3. 753, P0. 05). The value of the difference between WaveScan and subjective refraction was 5. 87o±6. 19o for the axis and the difference between OPD-Scan Ⅲ and subjective refraction was 3. 82o±3. 95o. There was statistic significance (t=2. 817, P=0. 006). CONCLUSION: For sphere and cylinder, WaveScan generated some deviation relative to subjective refraction. The Nidek OPD-ScanⅢ gives more accurate measures of objective refraction when compared with subjective refraction.
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Objective To evaluate the influence of black dots,isolated line above the best correct visual acuity and multiple lines containing the best correct visual acuity in the accuracy of Jackson cross cylinder examination.Methods Forty students were chosen(11 males,29 females,between 24 to 29 years old).Routine examination of phoropter was used to check under the maximum plus to maximum visual acuity(MPMVA) status.The sequence of three fixation targets was chosen randomly.Astigmatism chart was used to judge the best one when the different results were obtained.Results Among the 80 eyes of 40 students,12 eyes were spherical(the cylinder degree below 0.25 DC).The response of three fixation targets was the same in 19 eyes(27.9%),23 eyes(33.8%)were sensitive to the black dots target,14 eyes(20.6%)were sensitive to the isolated line above the best correct visual acuity,12 eyes(17.6%) were sensitive to multiple lines containing the best correct visual acuity.Kruska Wallis Test was used to detect the difference among three groups.No significant difference was found(?2 =4.026,P=0.134).Conclusion According to the efficiency of examination,communication and judgment,black dots target is recommended although no difference is detected among three fixation targets.
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PURPOSE: To evaluate correlations with refractive error, astigmatism and uncorrected visual acuity after Ortho-K LKTM lens wear. METHODS: Sixty-one eyes of 32 patients who had been wearing reverse geometry lenses for over 5 weeks were recruited. Uncorrected visual acuity, subjective refraction on retinoscopy, objective refraction measured by an autorefractometer, and corneal astigmatism were measured by corneal topography before, at 2 days, and 1, 3, and 5 weeks after lenses fitting. RESULTS: Uncorrected visual acuity improved from 0.12+/-0.10 to 0.95+/-0.15 after 5 weeks. Subjective refraction on retinoscopy and objective refraction measures with the autorefractometer were -3.52+/-1.65D and -4.06+/-1.73D, respectively before wearing the lenses. These decreased to -0.08+/-0.40D and -1.98+/-2.04D, respectively after 5 weeks. The astigmatism detected by corneal topography improved from 0.93+/-0.49 to 1.20+/-1.03 after 5 weeks. Uncorrected visual acuity was correlated with the refractive error measured by subjective refraction with retinoscopy rather than that by objective refraction with the autorefractometer. Corneal astigmatism measured by corneal topography correlated with the refraction detected by the autorefractometer. CONCLUSIONS: Subjective refraction by retinoscopy rather than refraction found objectively using the autorefractometer, was highly correlated with uncorrected visual acuity (r=0.77~0.87) which seems to be useful in evaluating myopia patients. The astigmatism determined by autorefractometer examination had high correlation with that determined by corneal topography (r=0.51~0.76). This result appears useful in decisions related to the decentering of lenses.
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Humans , Astigmatism , Corneal Topography , Myopia , Refractive Errors , Retinoscopy , Visual AcuityABSTRACT
Authors decided to test whether differences occurred in automated and subjective refraction in untreated, PRK, and LASIK-treated eyes. Ninety six eyes of 50 patients(96 eyes) who underwent PRK(57 eyes) or LASIK(39 eyes) for myopia and myopic astigmatism were routinely autorefracted with the CANON RK-3 before subjective refraction was done, using several parameters. This two procedures were done preoperation and 3 months after operation. In comparing the postoperative(PRK, LASIK) results, automated refraction showed more myopia and higher cylinder power, without significant difference in refractive axis, than those of subjective measurement. The difference of cylinder power were found in the cases of large ablation depth(above 100micrometer), high degree of eccentric ablation(above 0.25 mm), LASIK operation. The significant differences of cylinder power and axis were found in the cases of high degree of eccentric ablation(above 0.25 mm). So we recommend the method of subjective refraction before PRK and LASIK operation instead of using automated refraction. Postoperatvely, we also should evaluate the postoperative status of the patient by subjective refraction. And we should decide the amount of ablation in case of retreatment by subjective refraction, instead of autorefraction. We have to be cautious of evaluating the automated refraction results after operation, especially in cases of large ablation depth, high degree of eccentric ablation, and LASIK.