Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: EC:2.7.10.2 (focal adhesion kinase)
 44,029 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The refractive results of 43 consecutive triple procedures (transplant, cataract extraction, and lens implant) performed by one surgeon were analyzed. Twenty-one out of 43 eyes achieved refractive errors within 2 diopters (D) of emmetropia. The mean refractive error was -1.79 D, and the mean corneal astigmatic error was 2.75 D. Seventy percent of the eyes achieved 20/40 or better corrected acuity. Forty-four percent had 20/80 or better uncorrected acuity. Using the average postoperative keratometry readings from other recent transplant cases and an updated A constant in the SRK regression formula would have placed 39 of 43 eyes (91%) within 2 D of emmetropia with a mean refractive error of -0.07 D. The use of recent keratometry readings in a multiple regression formula is recommended to improve refractive results with the triple procedure.
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PMID:Intraocular lens powers used in the triple procedure. Effect on visual acuity and refractive error. 390 37

The SRK Regression formula for intraocular lens power calculation was used to predict postoperative emmetropia in two series of routine cataract operations using different posterior chamber lenses. More accurate results were obtained when the intraocular lenses were used in one dioptre steps. Some practical points about the routine use of ultrasound are made.
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PMID:Intraocular lens power calculation using the SRK formula: a clinical study. 390 47

Mathematical error analysis shows that the prognosis of IOL powers on the basis of theoretical optical formulas for calculating lens power is no more accurate than the regression (SRK) formula. The minimum error in a recommended lens power is at present between +/- 0.6 and +/- 1.0 D. As a result of this range of error there is a range of equivalence of the two formulas, and the vast majority of cataract patients (85%) are within this range. However, in hyperopic eyes the SRK formula is clearly superior to the theoretical optical formulas for a clinically useful prognosis.
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PMID:[Equivalency of different methods of measuring lens power]. 406 76

The accuracy of prediction of postoperative refractive error was evaluated in 175 patients with extracapsular cataract extraction and a Shearing-style posterior chamber intraocular lens. The Binkhorst, Colenbrander - Hoffer and SRK formulas were all less accurate in patients with an axial length greater than or equal to 24.5 mm. The standard error of the estimates of the Binkhorst formula was 1.2 diopters, the Colenbrander - Hoffer formula 1.18 diopters and the SRK formula 0.90 diopters. A new intraocular-lens formula for axial myopes was derived by polynomial regression analysis with a standard error of the estimate of 0.85 diopters. This new formula was accurate within 1 diopter in 79% of axial myopes compared to 71% for the SRK , 66% for the Colenbrander - Hoffer and 64% for the Binkhorst formulas. Regression analysis of a surgeon's own patient data can further improve the accuracy of prediction of the post-operative refraction.
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PMID:A new posterior chamber intraocular lens formula for axial myopes. 673 51

The accuracy of intraocular lens (IOL) power calculation was evaluated in a multicenter study of 822 IOL implantations using the Binkhorst II, Sanders/Retzlaff/Kraff (SRK I, SRK II, SRK/T), Holladay, and Olsen formulas. All but the first of these were optimized in retrospect with calculation of the SRK A-constant, the Holladay surgeon factor, and the Olsen pseudophakic anterior chamber depth (ACD) for each lens style. The ACD prediction of the Olsen formula was based on a previously described regression formula incorporating preoperative ACD, corneal height, axial length, and lens thickness. Among the optical IOL power calculation formulas, the highest IOL power prediction error was found with Binkhorst's and the lowest with Olsen's, which was more accurate than the SRK/T and the Holladay formulas (P < .05). The SRK/T formula was significantly more accurate than the original SRK regression formulas (P < .001). When analyzed for axial length dependence, all formulas showed the least error in the normal range. Error of the Olsen formula was lower than that of the others in the axial length interval 20 mm to 26 mm. No differences in accuracy were found between the optical IOL calculation formulas in eyes with an axial length above 26 mm (P < .05). The accuracy of IOL power calculation can be improved with optical formulas using newer-generation ACD-prediction algorithms.
J Cataract Refract Surg 1995 May
PMID:Intraocular lens power calculation with an improved anterior chamber depth prediction algorithm. 767 70

The study included 188 patients, in which a posterior chamber intraocular lens was implanted after extracapsular cataract extraction. After modifications of the intraocular lens constants (SRK formula and SRK II formula) and correction of the axial length measurements (Colenbrander-Hoffer formula) had been made, the mean differences between the actual postoperative spherical equivalent and that predicted by the three formulas were -0.23D, -0.22D and -0.46D, respectively. More than +/-1.0D deviation from the predicted postoperative refraction occurred in about one-third of the cases. Inter-observed discrepancy regarding the accuracy of the preoperative measurement of the ocular axis length is suggested to be the main cause of unpredicted postoperative refractive errors.
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PMID:The refractive error after implantation of a posterior chamber intraocular lens. The accuracy of IOL power calculation in a hospital practice. 788 61

Phacoemulsification with capsulorhexis reduces the surgical variability and may result in a more predictable refractive outcome. To evaluate the prediction accuracy with current IOL power prediction formulas, we reviewed a retrospective series of 628 phacoemulsification cases, including 148 short (< 22 mm) and 80 long (> 25 mm) eyes. Using the Binkhorst II formula and the manufacturer's recommended anterior chamber depth (ACD) values, the mean absolute refractive prediction error was 0.56 diopters (D). This error could be reduced to 0.51 D by retrospectively optimizing the ACD values for each lens type. Under similar least error conditions, the mean error was 0.51 D with the SRK/T formula and 0.47 D with the Olsen formula (P < .01). The Binkhorst formula overestimated the refraction in short eyes and underestimated the refraction in long eyes. The SRK/T and the Olsen formula were unbiased with the axial length. We hypothesize that the high prediction accuracy may be partially explained by a more predictable pseudophakic ACD with the current surgical technique.
J Cataract Refract Surg 1993 Nov
PMID:Phacoemulsification, capsulorhexis, and intraocular lens power prediction accuracy. 827 Nov 64

A new formula, the Hoffer Q, was developed to predict the pseudophakic anterior chamber depth (ACD) for theoretic intraocular lens (IOL) power formulas. It relies on a personalized ACD, axial length, and corneal curvature. In 180 eyes, the Q formula proved more accurate than those using a constant ACD (P < .0001) and equal (P = .63) to those using the actual postoperative measured ACD (which is not possible clinically). In 450 eyes of one style IOL implanted by one surgeon, the Hoffer Q formula was equal to the Holladay (P = .65) and SRK/T (P = .63) and more accurate than the SRK (P < .0001) and SRK II (P = .004) regression formulas using optimized personalization constants. The Hoffer Q formula may be clinically more accurate than the Holladay and SRK/T formulas in eyes shorter than 22.0 mm. Even the original nonpersonalized constant ACD Hoffer formula compared with SRK I (using the most valid possible optimized personal A-constant) has a better mean absolute error (0.56 versus 0.59) and a significantly better range of IOL prediction error (3.44 diopters [D] versus 7.31 D). The range of error of the Hoffer Q formula (3.59 D) was half that of SRK I (7.31 D). The highest IOL power errors in the 450 eyes were in the SRK II (3.14 D) and SRK I (6.14 D); the power error was 2.08 D using the Hoffer Q formula. The series using overall personalized ACD was more accurate than using an axial length subgroup personalized ACD in each axial length subgroup. The results strongly support replacing regression formulas with third-generation personalized theoretic formulas and carefully evaluating the Holladay, SRK/T, and Hoffer Q formulas.
J Cataract Refract Surg 1993 Nov
PMID:The Hoffer Q formula: a comparison of theoretic and regression formulas. 1718 72

Although available empirically derived and theoretical formulas perform adequately for eyes of average axial length, both have been shown to be deficient for eyes that have unusually short and long axial lengths. I developed a formula based on a theoretical model eye in which anterior chamber depth is related to axial length and keratometry. A relationship between the A-constant and a "lens factor" is also used to determine anterior chamber depth. The location of the intraocular lens' principle planes of refraction is retained as a relevant variable in the formula, and the user need not know the material and construction of the lens and or its constant. I compared the new formula with the SRK II, Holladay, and SRK/T formulas in a group of 100 unselected patients and in selected subgroups of patients with average, short, and long axial lengths. The new formula was significantly more accurate than the other third-generation formulas and maintained its accuracy in the subgroups. The formula can be described as universal because it can be used for different lens styles and for eyes with short, medium, and long axial lengths.
J Cataract Refract Surg 1993 Nov
PMID:An improved universal theoretical formula for intraocular lens power prediction. 827 Nov 66

The oculometric features have been analysed in two groups of cataract patients, each comprising 30 subjects. All had undergone ECCE and insertion of biconvex Rayner 2 Superflex posterior chamber IOL. Using Binkhorst and SRK II routinely, the groups were given by a good fit between methods (discrepancy between emmetropia predictions numerically < 1 D) and a poor fit (actual discrepancy range 1.6-4.1 D, all with the same sign, the lower values being predicted by Binkhorst). A certain overlapping between groups was found regarding axial length and corneal curvature radius, the ranges being 21.5-25.1/22.7-29.9 mm and 7.3-8.5/7.2-8.1 mm, respectively. In contrast there was no overlapping regarding the ratio between axial length and corneal curvature radius; the ranges were 2.80-3.05 and 3.06-3.90 in the two groups. Evaluating the actual prediction errors by the two methods (follow-up after at least 4 months), they did not primarily pertain to very short or very long eyes, as usually advanced. Skew ratios between axial length and corneal curvature appeared more decisive. Possible implications for the current IOL prediction formulas, including the newer generations, are discussed.
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PMID:Intraocular lens prediction and oculometric harmony. With special reference to skew ratios between axial length and corneal curvature radius. 836 45


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