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AIM: To evaluate the accuracy of SRK/T, Haigis, Barrett Universal II and Wang-Koch modified SRK/T formula in the operation of cataract complicated by super-high myopia.METHODS: A total of 44 cases(52 eyes)with super-high myopia complicated with cataract who underwent phacoemulsification with tension ring implantation combined with intraocular lens implantation in our hospital from January 2020 to June 2021 were collected. SRK/T, Haigis, Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula were used to calculate the postoperative reserved diopter before surgery, and the actual diopter was measured by comprehensive optometry at 3mo after surgery. The mean absolute refractive error(MAE)of four formulas was obtained to evaluate the accuracy of the calculation formula.RESULTS: The MAE of SRK/T formula, Haigis formula, Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula were 0.86(0.56, 1.20), 0.79(0.56, 1.16), 0.68(0.30, 0.87), 0.65(0.43, 0.75)D, respectively, and MAE of SRK/T formula and Haigis formula were significantly higher than those of Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula(P<0.01). According to preoperative corneal curvature(K), enrolled patients were divided into K >46D group(12 eyes), 44D< K ≤46D group(24 eyes), and K ≤44D group(16 eyes). The MAE of SRK/T formula and Haigis formula were significantly higher than those of Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula in the three groups(P<0.01). According to preoperative axial length(AL), patients were divided into AL ≤30 mm group(24 eyes)and AL >30mm group(28 eyes). The MAE of SRK/T formula and Haigis formula in two groups were significantly higher than those of Barrett Universal Ⅱ formula and Wang-Koch modified SRK/T formula(P<0.05).CONCLUSIONS: Wang-Koch modified SRK/T formula and Barrett Universal Ⅱ formula are more accurate in predicting the degree of intraocular lens in patients with super-high myopia complicated with cataract.
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AIM: To compare the accuracy of different intraocular lens(IOL)calculation formulas in cataract patients with axial length longer than 28mm and a history of radial keratotomy(RK).METHODS: Retrospective study. The medical records of 19 cataract patients(29 eyes)after RK and with axial length longer than 28mm who underwent cataract surgery from January 2011 to July 2020 in Beijing Tongren Hospital were analyzed. The absolute error(AE)of the difference among three different formulas was calculated. AE refers to the absolute value between the actual spherical equivalent after cataract surgery and the spherical equivalent predicted by the IOL formula. The AE values of the three formulas and the percentages of eyes with AE≤0.5, 0.75, 1.0, and 2.0D were calculated and compared.RESULTS: The AE values of the three formulas were significantly different(χ2=8.759, P=0.013). The Barrett True-K formula had the smallest median AE, which was only 0.62(0.20, 1.15)D, followed by the Haigis formula 0.76(0.34, 1.26)D, and the Holladay 1(D-K)formula had the largest 1.01(0.49, 1.62)D. The percentages of affected eyes with AE ≤0.5, 0.75, 1.0, and 2.0D for the Barrett True-K formula were 48%, 59%, 69%, and 93%, which were equal to or higher than the other two formulas.CONCLUSION: The Barrett True-K formula is more recommended among the three formulas for cataract patients after RK and with axial length longer than 28 mm.
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Glaucoma and cataracts are the leading causes of blindness, and surgery is an important treatment option. Patients with glaucoma have clinical characteristics such as high intraocular pressure, shallow anterior chamber and short axial length, and the ocular structure is often altered after anti-glaucoma surgery like trabeculectomy. These changes also lead to differences in the accuracy of intraocular lens(IOL)refractive calculation between cataract surgery after anti-glaucoma surgery or combined glaucoma and cataract surgery and alone cataract surgery. Meanwhile glaucoma patients' individual clinical characteristics and structural changes caused by anti-glaucoma surgery have shown differences in the impact on the predictive accuracy of IOL diopters and the type of refractive drift. This article reviews the latest research advances in the causes of refractive error(RE), the characteristics of refractive drift, and the selection of the most appropriate IOL formula for glaucoma patients undergoing cataract surgery or cataract surgery after anti-glaucoma surgery or combined glaucoma and cataract surgery.
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Objective:To explore the types, gene mutation types and constituent ratio of thalassemia in Xiaoshan area of Hangzhou, and to analyze the value of test index of erythrocyte parameter calculation formula (Matos & Carvalho Index, MCI) in differential diagnosis.Methods:Using the method of retrospective analysis, 150 cases of thalassemia and 124 cases of iron deficiency anemia treated in Xiaoshan Hospital Affiliated to Hangzhou Normal University from January 2019 to April 2021 were included in the study to collect the diagnostic results of α and β-thalassemia genes, ferritin and erythrocyte parameters, the test indexes were compared and analyzed, and the value of MCI in differentiating thalassemia from iron deficiency anemia was analyzed.Results:In 150 cases of thalassemia, there were 58 cases of α-thalassemia (38.67%), of which 8 cases (5.33%) were complicated with iron deficiency; there were 88 cases of β-thalassemia (58.67%), of which 3 cases (2.00%) were complicated with iron deficiency; αβ-compound thalassemia occurred in 4 cases (2.67%). The proportion of α-thalassemia was lower than β-thalassemia, the difference was statistically significant (χ 2 = 12.01, P = 0.001) . Four kinds of α-thalassemia allele were detected in 58 cases of α-thalassemia, mainly -- SEA, a total of 48 cases (82.76%); eight gene mutation types were detected in 88 cases of β-thalassemia, of which CD41-42 was the most, a total of 33 cases (37.50%). The basic parameters of β-thalassemia, red blood cell (RBC), hemoglobin (HGB) and red blood cell specific volume (HCT) were lower than those of α-thalassemia ( t = - 2.88, - 3.49, - 4.33, P < 0.05); mean hemoglobin concentration (MCHC) and red cell volume distribution width (RDW) were higher than those of α-thalassemia ( t = 3.22, 2.43, P < 0.05). The MCI value of thalassemia group was significantly higher than that of iron deficiency anemia group (23.14 ± 1.73 vs 20.47 ± 1.45, t = 13.61, P < 0.001). The area under the curve of MCI (AUC) = 0.885. The diagnostic cut-off point was set according to the maximum Jorden index method (0.594). The diagnostic cut-off point in this study was 21.375, with a sensitivity of 82.0% and specificity of 77.4%. Conclusions:The genotyping of thalassemia in Xiaoshan area of Hangzhou indicates that β-thalassemia is dominant, with the most mutations in CD41-42 genotype, followed by α-thalassemia, with -- SEA genotype mutation most. MCI has great screening value in identifying small cell anemia.
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@#AIM:To evaluate the effect of keratometry on the calculation accuracy of intraocular lens(IOL)diopter in patients with normal axial cataract.METHODS:Totally 157 cases(157 eyes)with age related cataract were collected in Kaifeng Central Hospital from June 2020 to June 2021. Patients were divided into 3 groups according to keratometry: group A(53 eyes)(K<42D), group B(55 eyes)(42D≤K≤46D), group C(49 eyes)(K>46D). The IOL diopter was calculated by SRK/T, Hoffer Q, Holladay 2, Haigis, Kane and Barrett Ⅱ formulas respectively. Subjective optometry was performed after 1mo operation. The average refractive prediction error(RPE)and mean absolute error(MAE)were calculated, and their differences were compared and analyzed.RESULTS:There were significant difference between RPE of each formula and 0D in groups A and C(<i>P</i><0.05), and Barrett Ⅱ formula was significantly different with SRK/T, Hoffer Q, Holladay 2 and Haigis formula(<i>P</i><0.01), but was no significantly different with Kane formula in RPE(<i>P</i>>0.01). There was no significant difference in RPE between group B and 0D(<i>P</i>>0.05). The ratio of Barrett Ⅱ formula in MAE≤0.5D in group A was significantly higher than SRK/T, Hoffer Q, Holladay 2 and Haigis formula(all <i>P</i><0.01), but there was no significant difference compared with Kane formula(<i>P</i>>0.01). In group B, there was no significant difference among Barrett Ⅱ formula and the other formulas in the ratio of MAE≤0.5D and ≤1.0D(all <i>P</i> >0.01). In group C, the ratio of SRK/T and Hoff Q formula in MAE≤0.5D was lower than Barrett Ⅱ formula(all <i>P</i><0.01), and there were no significant difference among Barrett Ⅱ formula and the other formulas in the ratio of MAE≤1.0D(<i>P</i> >0.01).CONCLUSION:If K<42D or K>46D before operation, the commonly used formulas will produce refractive error, but the accuracy of Kane and Barrett Ⅱ formulas are still higher than other formulas.
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Objective:To compare the accuracy of IOLMaster 700 and IOLMaster 500 in intraocular lens (IOL) power calculation.Methods:A cross-sectional study was conducted.Two hundred and sixty-two eyes of 262 patients who underwent phacoemulsification combined with IOL implantation at the Eye Hospital of Wenzhou Medical University from November 2018 to November 2019 were enrolled.Preoperative biometry for cataract surgery was performed using IOLMaster 700 and IOLMaster 500.IOL power was calculated through the built-in formulas, Haigis, Holladay Ⅰ, Hoffer Q and SRK/T of the two devices.The difference in IOL power calculation between the two devices was analyzed through the prediction error of IOL power calculation using different formulas across different axial length (AL) ranges.This study complied with the Declaration of Helsinki.The study protocol was approved by the Ethics Committee of the Eye Hospital of Wenzhou Medical University (No.2020-038-K-33). Written informed consent was obtained from each patient before the surgery.Results:There was no significant difference in mean absolute error (MAE) between IOLMaster 700 and IOLMaster 500 using Haigis, Hoffer Q and SRK/T over the entire AL range (all at P >0.05). The MAE of IOLMaster 500 was 0.47 (0.24, 0.90) D, which was significantly lower than 0.50 (0.28, 0.99) D of IOLMaster 700 using Holladay Ⅰ formula ( Z=-3.120, P=0.002). When AL was <22.0 mm and ≥24.5 mm-<26.0 mm, there was no significant difference in MAE between the two devices using the four formulas (all at P >0.05). When AL was ≥22.0 mm-24.5 mm, there was no significant difference in the MAE between the two devices using Haigis, Hoffer Q and SRK/T (all at P >0.05), but 0.42 (0.18, 0.75) D from IOLMaster 500 was smaller than 0.45 (0.25, 0.79) D from IOLMaster 700 using Holladay Ⅰ, showing a statistically significant difference ( Z=-3.487, P <0.001). But the difference was negligible and therefore was of no clinical significance.When AL was ≥26.0 mm, there was no statistically significant difference in the MAE between the two devices using Haigis, Holladay Ⅰ and SRK/T, but 0.66 (0.38, 1.00) D from IOLMaster 500 was significantly smaller than 0.98 (0.62, 1.32) D from IOLMaster 700 using Hoffer Q ( Z=-3.046, P=0.002). Conclusions:The refractive prediction accuracy of IOLMaster 700 and IOLMaster 500 using Haigis, Hoffer Q and SRK/T is similar over the entire AL range.For patient with long AL, the IOL calculation from IOLMaster 700 using Hoffer Q is significantly larger than that from IOLMaster 500, which requires extra caution in clinical practice.The accuracy of IOLMaster 700 and IOLMaster 500 for IOL prediction is very similar.
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@#AIM: To compare and study the differences of eyeball biometric measurements among Han, Hani and Yi nationality in Honghe Hani and Yi Autonomous Prefecture(Honghe Prefecture), and prediction accuracy of the intraocular lens(IOL)degree by SRK-T and Haigis formulas in the different eye axes, to provide further objective clinical evidence for the majority of basic-level hospitals and the blind prevention and treatment projects in minority areas.<p>METHODS: Selected 186 cases(200 eyes)cataract patients in our department, divided them into three groups according to different nations, get their eyeball biometric measurements(ocular axial length, anterior chamber depth and corneal curvature)by A-ultrasound combined with corneal curvature meter and corneal topography, and then compared the differences. According to the different eye axes, they were divided into three groups and then randomly divided into two groups. SRK-T and Haigis formulas were used to predict the IOL degree, and collected postoperative optometry results, calculated the absolute prediction error, then conducted statistical analysis. <p>RESULTS: There were no difference in the mean axial length, mean anterior chamber depth and mean corneal curvature(measured respectively by corneal topography and corneal keratometer)in the different ethnic groups(<i>P</i>>0.05), and the mean corneal curvature measured by the two methods had no difference(<i>P</i>>0.05). There were no difference of the mean corneal curvature measured by the two methods in the three axial eye groups(<i>P</i>>0.05)and in the same axial eye group(<i>P</i>>0.05). There were no difference in the absolute error of the two IOL measurement formulas in the three eye axis groups(<i>P</i>>0.05). The absolute error calculated by SRK-T formula for the short and the middle eye axis groups were smaller, while it calculated by Haigis formula for long eye axis group was smaller.<p>CONCLUSION: In our department, there are no statistical difference in the eye biometrics of Han, Yi and Hani nationality. Corneal curvature measured by corneal topography and corneal keratometer have no significant difference. SRK-T and Haigis formula both have high predictive value for IOL degree, SRK-T formula has smaller predictive error for patients which with short and middle eye axis, and Haigis formula has better predictive value for the long ones.
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@#AIM: To evaluate the predictability of Olsen formula for postoperative refractive power in patients with high myopia complicated with cataract.<p>METHODS: This retrospective study reviewed 65 patients(101 eyes)with high myopia and who had phacoemulsification combined with intraocular lens implantation from October 10th 2016 to August 20th 2019 in our hospital. They were divided into three groups according to the axis length: group A(26mm <AL≤28mm)17 cases(29 eyes), group B(28mm<AL≤30mm)26 cases(41 eyes), group C(AL>30mm)22 cases(31 eyes). The postoperative theoretical diopter(that is, the preoperative predictive diopter of each formula corresponding to the degree of IOL implanted)of intraocular lens was calculated by SRK/T, Haigis and Olsen formulas of IOL-master. The actual postoperative 3mo diopter was recorded and the absolute refractive error(MAE)was calculated.<p>RESULTS: The postoperative 3mo MAE in the three groups calculated with Olsen formula was 0.15(0.04, 0.22), 0.19(0.14, 0.27), 0.26(0.115, 0.455)D respectively(<i>P</i>>0.05). For patients with the same axial length, the postoperative 3mo MAE of Olsen formula was the smallest. The Bland-Altman method was used to analyze the consistency between the postoperative theoretical diopter and the postoperative 3mo actual diopter. The results showed that the postoperative 3mo actual diopter was the closest to the postoperative theoretical diopter of the Olsen formula, while the postoperative theoretical diopter of the SRK/T formula was the worst.<p>CONCLUSION: For patients with high myopia and cataract, the accuracy and stability of Olsen formula is better than that of SRK/T and Haigis formula, and Olsen formula is least affected by eye axis length.
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Objective Sixteen common blood osmotic pressure calculation formulas were investigated to evaluate the calculation formula of the plasma osmotic pressure formula and the freezing point depression method.The collected data were used to simulate a formula that was consistent with the patient′s plasma osmotic pressure.Methods The osmotic pressure of plasma was measured by the freezing point descent method.Plasma sodium (Na), potassium (K), chloride (Cl), glucose (Glu), and urea (Urea) concentrations were measured by using a Vitros 5.1dry chemistry analyzer.Sixteen formulas were used to calculate the corresponding plasma osmotic pressure.The Passing-Bablok regression was used to determine the goodness of fit and paired t test was performed with the measured values.A multiple linear regression and paired t test method was used to fit a formula that most closely matched the measured values.Results The formula of plasma osmotic pressure and the measured value was the most consistent with the formula 1.86 (CNa+CK) +CGlu+CUrea+10;the regression formula using multiple linear regression was 1.86CNa+2.75CK+1.16CGlu+0.92CUrea+5.77.Conclusion It is tentatively concluded that the formula 1.86CNa+2.75CK+1.16CGlu+0.92CUrea+5.77can be used as the formula for calculating plasma osmolality.
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Objective To observe the difference of the human body surface area (BSA) formula based on three-dimensional measurement in practical application. Methods The data of 1249 college students (639 males, 610 females) from physical health examination in 2018 were selected. Using the one-way factorial analysis of variance (ANOVA), correlation analysis and Bland-Altman comparative analysis, comparisons between the BSA values using four BSA calculation formulas based on three-dimensional measurement and with the traditional formula measurement by Yongmei Hu's were made as well. Results There were significant statistical differenes between the BSA values of the formulas (P 0. 985) were also rather high. Results from Hu Yong-mei's formula were higher than the other four 3D formulas in both genders, with the BSA of males 7. 32%-12. 11% higher than the mean while female BSA values were 5. 53%-11.72% above the average. It has been shown from the Bland-Altman analysis that the formula from ChiYuang Yu had the highest consistency score (95 % CI 1.021-1.034) among the selected four 3D measurement formulas. Conclusion Within the four BSA formulas based on 3D measurement principle, ChiYuang Yu's formula is relatively more suitable to estimate the BSA values of both Chinese males and females.
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Objective:To explore the role of clinical pharmacists in the development of individualized drug treatment regimens for the osteosarcoma children with irregular body weight .Methods:Clinical pharmacists involved in the calculation of body weight surface area increased to that of adult for one case of osteosarcoma child during the chemotherapy , comparatively analyzed the suitable calcula-tion formula of surface area for the children in our country and helped clinicians make accurate dose of chemotherapy drugs .Mean-while, according to the pathological and physiological characteristics of the child , clinical pharmacist also provided advice on adjuvant drug use such as antiemetic regimen etc .Results:Physicians adopted the suggestions of clinical pharmacists and the chemotherapy was successfully completed .Overdose adverse reactions were avoided without the use of foreign general calculation formula of body surface area for the overweight child , and inadequate dose was also avoided for the conservative treatment , which could lower the risk of re-duced potential anticancer efficacy .Conclusion:Clinical pharmacists can help doctors perform safer and more effective drug treatment program and reduce adverse drug reactions in the treatment of special patients through participation in the development of individualized medication for cancer children to obtain maximum profit .
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PURPOSE: To assess the refractive change and prediction error after temporary intraocular lens (IOL) removal in temporary polypseudophakic eyes using IOL power calculation formulas and Gills' formula. METHODS: Four consecutive patients (7 eyes) who underwent temporary IOL explantation were enrolled. Postoperative refractions calculated using IOL power calculation formulas (SRK-II, SRK-T, Hoffer-Q, Holladay, and the modified Gills' formula for residual myopia and residual hyperopia) were compared to the manifest spherical equivalents checked at 1 month postoperatively. RESULTS: The mean ages of temporary piggyback IOL implantation and IOL removal were 6.71 +/- 3.68 months (range, 3 to 12 months) and 51.14 +/- 18.38 months (range, 29 to 74 months), respectively. The average refractive error was -13.11 +/- 3.10 diopters (D) just before IOL removal, and improved to -1.99 +/- 1.04 D after surgery. SRK-T showed the best prediction error of 1.17 +/- 1.00 D. The modified Gills' formula for myopia yielded a relatively good result of 1.47 +/- 1.27 D, with only the variable being axial length. CONCLUSIONS: Formulas to predict refractive change after temporary IOL removal in pediatric polypseudophakia were not as accurate as those used for single IOL implantation in adult eyes. Nonetheless, this study will be helpful in predicting postoperative refraction after temporary IOL removal.
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Female , Humans , Infant , Male , Cataract/congenital , Cataract Extraction , Device Removal , Hyperopia/etiology , Lens Implantation, Intraocular/methods , Lenses, Intraocular , Myopia/etiology , Prospective StudiesABSTRACT
PURPOSE: To assess the refractive change and prediction error after temporary intraocular lens (IOL) removal in temporary polypseudophakic eyes using IOL power calculation formulas and Gills' formula. METHODS: Four consecutive patients (7 eyes) who underwent temporary IOL explantation were enrolled. Postoperative refractions calculated using IOL power calculation formulas (SRK-II, SRK-T, Hoffer-Q, Holladay, and the modified Gills' formula for residual myopia and residual hyperopia) were compared to the manifest spherical equivalents checked at 1 month postoperatively. RESULTS: The mean ages of temporary piggyback IOL implantation and IOL removal were 6.71 +/- 3.68 months (range, 3 to 12 months) and 51.14 +/- 18.38 months (range, 29 to 74 months), respectively. The average refractive error was -13.11 +/- 3.10 diopters (D) just before IOL removal, and improved to -1.99 +/- 1.04 D after surgery. SRK-T showed the best prediction error of 1.17 +/- 1.00 D. The modified Gills' formula for myopia yielded a relatively good result of 1.47 +/- 1.27 D, with only the variable being axial length. CONCLUSIONS: Formulas to predict refractive change after temporary IOL removal in pediatric polypseudophakia were not as accurate as those used for single IOL implantation in adult eyes. Nonetheless, this study will be helpful in predicting postoperative refraction after temporary IOL removal.
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Female , Humans , Infant , Male , Cataract/congenital , Cataract Extraction , Device Removal , Hyperopia/etiology , Lens Implantation, Intraocular/methods , Lenses, Intraocular , Myopia/etiology , Prospective StudiesABSTRACT
PURPOSE: To evaluate the accuracy of various formulas installed in IOLMaster software which uses partial coherence interferometry for axial length measurement. METHODS: This retrospective comparative study included 81 eyes of consecutive patients who had uneventful cataract surgery with implantation of Acrysof single piece (SA60AT) IOL. Axial length was measured with IOLMaster and IOL power was calculated using various formulas, including SRK II, SRK/T, Holladay 1, Haigis, and Hoffer Q. Subjects were stratified by axial length into Groups A (axial length or = 25.00 mm). Target refractions of the five formulas were compared to the postoperative manifest refraction at 1 month. RESULTS: The five formulas showed no difference in predicting postoperative refractive errors among all of the groups. CONCLUSIONS: Five formulas installed in IOLMaster software provided equivalent predictions of postoperative refractive error regardless of axial length.
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Humans , Cataract , Eye , Interferometry , Lenses, Intraocular , Refractive Errors , Retrospective StudiesABSTRACT
Although most available IOL power calculation formulas perform accurately for eyes of average axial length, they have been shown to be inaccurate for eyes that have unusually short and long axial length. To compare the prediction accuracy of new Hoffer Q with SRK-II formula, we reviewed, retrospectively, a series of 225 ECCE with PCL implantation cases, including 106 Hoffer Q group and 119 SRK-II group, each of which was further divided into subgroups based on axial length. The Hoffer Q formula overestimated the refraction and resulted in more myopic shift and was less accurate than SRK-II in all length eyes, except short length eyes. In short length eyes, both formulas had similar mean error and mean absolute error but Hoffer Q formula was more accurate than the SRK-II in +/- 0.5D prediction proportion.