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PubMedDate not supplied

Comparison of LASIK outcomes with the Alcon LADARVision4000 and the VISX STAR S2 excimer lasers using optimized nomograms.

PURPOSE: To evaluate the difference in clinical outcomes between LASIK patients treated with the Alcon LADARVision4000 laser and the VISX STAR S2 laser using optimized nomograms. METHODS: Data from 572 LASIK surgeries of two groups that were sequentially performed by one surgeon were retrospectively reviewed. The first group of 286 eyes were the last cases performed with the VISX STAR S2 laser. Following these surgeries, a second group of 286 eyes were the first cases performed with the Alcon LADARVision4000 laser, after an initial 50-eye adaptation period. Treatments were guided by the Refractive Surgery Consultant software. RESULTS: For myopic eyes 3 months postoperatively, the percentage of eyes with uncorrected visual acuity (UCVA) > or = 20/20, accuracy of treatment within +/- 0.5 D, and loss of > or = 2 lines of best spectacle-corrected visual acuity (BSCVA) for the LADARVision4000 and STAR S2, respectively was: 89% vs 63%, 84% vs 80%, and 0.8% vs 3.8%. For hyperopic eyes 3 months postoperatively, the percentage of eyes with UCVA > or = 20/20, accuracy of treatment within +/- 0.5 D, and loss of > or = 2 lines of BSCVA for the LADARVision4000 and STAR S2, respectively was: 74% vs 33%, 69% vs 74%, and 2% vs 18.5%. CONCLUSIONS: Although good results are evident for both platforms, superior results were observed with the Alcon LADARVision4000 laser.

Adolescent↗
PubMed1984

Nomogram for calculation of stenotic cardiac valve areas from cardiac output and mean transvalvular gradient.

In 15 patients (group 1) with isolated mitral stenosis and in 14 patients (group 2) with isolated aortic stenosis the stenotic valve areas were calculated according to: A) Gorlin's formula; B) Hakki's simplified formula, using mean mitral gradient by planimetry or peak-to-peak aortic gradient; C) the three-point simplified formula, using mean gradient calculated by the three-point method for both mitral and aortic valve. The three-point method is definitely easier to use than planimetry. The values (mean +/- SD) of mitral valve areas in group 1 patients were, respectively: 1.56 +/- 0.63 cm2; 1.56 +/- 0.55; 1.51 +/- 0.53. The values of aortic valve areas in group 2 patients were: 0.91 +/- 0.63; 0.77 +/- 0.41; 0.88 +/- 0.52. An excellent correlation was shown between the valve area calculated by Gorlin's formula and both Hakki's simplified formula and the three-point simplified formula. For aortic valve area the correlation is even better if the mean gradient by the three-point method is used instead of the peak-to-peak gradient. On the basis of the simplified formula, a nomogram was constructed which allows an immediate calculation of valve areas from cardiac output and transvalvular gradient.

Adult↗
PubMed1987

Nomograms for the prediction of patient's plasma volume in plasma exchange therapy from height, weight, and hematocrit.

The knowledge of plasma volume (PV) is a basic requirement for the standardization of plasma exchange therapy. PV has to be determined by calculation, as the measurement of PV before every plasma exchange is too cost- and time consuming. A known correlation with measured values results from calculation of plasma volume by means of patient's height and weight. But the present equations are only reliable at normal hematocrit. For this reason we modified the Retzlaff-equations and compared the validity of plasma volume predictions, calculated by these and own equations, with plasma volume measured by the 51Cr-method in 59 patients with pathological hematocrit. The correlation coefficient was 0.82 for men and 0.81 for women (2 0.001) with the modified Retzlaff-equations. On the average the relative error was -1.5% for all and 2.8% for fat and thin men. No significant improvement of accuracy was achieved with other equations. Thus, plasma volume can accurately be calculated from height, weight, and hematocrit with our modified Retzlaff-equations in patients with pathological hematocrit, even if they are very fat or thin. Nomograms for men and women were constructed in order to facilitate the calculation.

Blood Volume Determination↗
PubMed2004

Nomograms of sonographic measurements throughout gestation of the fetal hard palate width, length and area.

OBJECTIVE: To assess the feasibility of sonographic depiction of the fetal hard palate and secondarily to create nomograms throughout gestation of its sonographic width, length and area. METHODS: This was a cross-sectional study of pregnant patients between 15 and 41 weeks' gestation. Inclusion criteria consisted of well-established dates (confirmed by early ultrasound), and singleton, non-anomalous fetuses. Sonographic measurements obtained included biparietal diameter, head circumference, abdominal circumference and femur length. Fetal hard palate measurements included maximum width, maximum length and the calculated area. Tables were prepared depicting the estimated mean +/- SD and 5(th), 50(th) and 95(th) centiles at each gestational week between 15 and 41 weeks. Pearson's correlation coefficient and associated P-values for the relationships between fetal hard palate measurements and other sonographic measurements and coefficients of variation for each of the fetal hard palate measurements were calculated. RESULTS: The study included 602 consecutive patients. The mean maternal age was 28.7 +/- 6.3 years, with median gravidity of 2 (range, 1-12) and parity 1 (range, 0-8). All attempts at obtaining fetal hard palate ultrasound measurements were successful. Mean fetal hard palate width (cm) = -0.73579345 + 0.11370432 x GA - 0.00083919 x GA(2) and SD = -0.017842055 + 0.005142475 x GA, where GA is gestational age in weeks. Mean fetal hard palate length (cm) = -0.82020463 + 0.11767777 x GA - 0.00092801 x GA(2) and SD = -0.043064317 + 0.006378869 x GA. Mean fetal hard palate area (cm(2)) = -2.40090641 + 0.17136556 x GA + 0.00097308 x GA(2) and SD = -0.603647741 + 0.040740282 x GA. Sonographic measurements of the fetal hard palate width, length and area correlated significantly and strongly with gestational age (all P < 0.001) and significantly but less strongly with femur length (P = 0.004). CONCLUSION: The fetal hard palate may be depicted sonographically with relative ease between 15 and 41 weeks' gestation and measurements of the fetal hard palate width, length and area correlate well with gestational age, biparietal diameter, abdominal circumference, sonographic estimated fetal weight, and femur length.

Adult↗
PubMedDate not supplied

Ultrasonographic fetal nomograms of anterior ventricular hemisphere ratio (AVHR) and posterior ventricular hemisphere ratio (PVHR) for early prenatal diagnosis of hydrocephalus.

Serial ultrasound scans were done in 150 fetuses between 14th to 22nd week of gestation to establish the nomograms of anterior ventricular hemisphere ratio (AVHR) and posterior ventricular hemisphere ratio (PVHR). Of 150 fetuses, 100 were in the high risk group for neural tube defect and 50 were in the control group. The study indicates that the value of AVHR decreases from 0.62 to 0.50 and PVHR from 0.60 to 0.50 between 14th to 22nd week of gestation. No statistical difference was observed in the values of AVHR and PVHR in high risk and low risk (control) cases (p > .001). The value of AVHR or PVHR greater than 0.5 after 18 weeks of gestation or more was considered pathological for hydrocephalus. In 2, out of 3 cases of hydrocephalus detected in our series, the value of AVHR and PVHR was 0.7 at 20 weeks and in the third case it was 0.6 at 18 weeks. All of these values were 3 SD above the normal for the period of gestation.

Cephalometry↗
PubMed2000

Experiences with a compound method for estimating the time since death. I. Rectal temperature nomogram for time since death.

The temperature-based nomogram method for estimation of the time period since death was used at the scene of death as the primary method within a compound method in 72 consecutive cases. The situation and cooling conditions inspected and evaluated by the forensic pathologist at the scene are described as far as necessary to enable handling of the method. A comparison of the estimated period since death with the period determined by the police investigations demonstrates the reliability of the method. There were no contradictions in any of the 60 cases between the period of death estimated by this method and that determined by the police investigations. The criminal investigations were effectively supported in the earliest stages in 11 cases despite the fact that the period estimated was of considerable duration.

Adolescent↗
PubMed2000

Prediction of creatinine clearance from serum creatinine in patients with rheumatoid arthritis: comparison of six formulae and one nomogram.

The estimation of glomerular filtration rate is important for the medical treatment of patients with rheumatoid arthritis (RA). However, the determination of endogenous creatinine clearance (Clcr) from a 24-h urine collection is an unreliable and time-consuming procedure. We therefore tested the accuracy of six equations and one nomogram for the prediction of Clcr from serum creatinine (Scr) in 38 patients with RA and 20 controls. A positive correlation was found for all methods in the controls (r = 0.83-0.94) and RA patients (r = 0.51-0.69). The methods did not overestimate Clcr in RA. In the RA group the simple formula published by Cockcroft [Clcr = ((140 - age) x body weight)/(72 x Scr), x 0.85 for females] showed the best correlation with the measured Clcr. In RA the Cockroft formula can reliably be used to predict Clcr from Scr.

Adult↗
PubMed1983

Nomograms for the assessment of Farnsworth-Munsell 100-hue test scores.

Although the Farnsworth-Munsell 100-hue test is a sensitive means of evaluating congenital and acquired color vision deficiencies, using the data it provides involves complex calculations. We have developed two nomograms that permit the clinician to determine quickly and easily whether a given score is normal for the patient's age and whether the difference between fellow eyes is within the normal range.

Adult↗
PubMed1983

On the use of nomograms to determine the elastic property ratios of orthodontic arch wires.

With an 0.012 inch stainless steel arch wire as the base line, a series of calculating charts which express the strength, stiffness, and range ratios of orthodontic arch wires is introduced. In each case, both the bending and the torsional stress states are computed over a broad range of wire sizes. Three distinct situations are addressed: the over-all spectrum of elastic property ratios among stainless steel, nickel-titanium, and beta titanium wires; the intra- and interproperty relationships of these wire compositions; and the role which elastic property ratios play in the selection of the right arch wire. Via these nomograms, clinicians will have another means available by which the plethora of wire compositions and cross sections may be assessed.

Dental Alloys↗
PubMed1975

Biochemical typing of hyperlipoproteinemia. The development of a nomogram.

The accurate biochemical typing of hyperlipoproteinemia would require quantification of lipoprotein fractions. At present, typing is frequently based on the lipoprotein electrophoresis pattern together with serum lipid analyses. Lack of facilities for lipoprotein electrophoresis has however focused the clinical interest for classification of hyperlipoproteinemia into other means of a simple biochemical typing. In the present study a nomogram was developed to allow biochemical typing of hyperlipoproteinemia from serum cholesterol and triglyceride values. Serum cholesterol was determined according to a Liebermann-Burchard reaction by the method of Cramer and Isaksson [1], serum triglycerides by the determination of glyceride glycerol according to Carlson [2], and serum lipoprotein electrophoresis was performed on agarose gel [3]. Cholesterol content [4] of alpha-lipoproteins ("alpha-LP cholesterol") was obtained in serum after the precipitation of very-low-density lipoproteins(VLDL) and low-density lipoproteins(LDL) by manganese chloride and heparin [5]. Preparative ultracentrifugation was performed in a one-step, gradient procedure [6] isolating VLDL, d less than 1.006, LDL, d 1.006--1.063 g/ml and high-density lipoprotein (HDL) including very-high-density lipoproteins, d greater than 1.063 g/ml, or alternatively at d 1.006 g/ml according to the procedure by Gustafson et al. [7].

Cholesterol↗
PubMed1980

A temperature conversion nomogram for glycosylated hemoglobin analysis.

Analysis of glycosylated hemoglobins by commercial mini-column methods was shown to vary linearly with the ambient temperature. However, the slopes of the temperature dependence lines for diabetic and healthy individuals was different. A method for temperature correction and a nomogram is proposed.

Chromatography↗
PubMed1988

A blood-gas nomogram of the chick fetus: blood flow distribution between the chorioallantois and fetus.

This paper presents equations for quantifying the relationships between the O2 and CO2 concentrations and tensions in the blood of the 18-day chick fetus. A blood-gas nomogram showing these relationships is presented. Starting with the reported chorioallantoic artery and vein gas tensions and using the blood-gas equations, the range of embryonic arterial and venous gas tensions as well as the distribution of the cardiac output and the degree of mixing between the chorioallantoic and embryonic circulations are explored. It is concluded that at least 65% of the blood in the chorioallantoic artery consists of blood of embryonic mixed venous composition. A model of the blood flow distribution is proposed in which chorioallantoic and embryonic flows are equal, with 70% of the blood returning from the tissues of the embryo going to the chorioallantois and vice versa.

Allantois↗
PubMed1996

Nomograms to help inform women considering Down's syndrome screening.

OBJECTIVE: To derive graphical information for use in counselling women considering whether or not to have maternal serum screening for Down's syndrome. DESIGN: Statistical modelling of the frequency distribution of estimated Down's syndrome risk for four marker combinations. RESULTS: Nomograms are provided showing for each maternal age: (a) the detection and false-positive rates, and (b) the proportion of pregnancies with different estimated risks. CONCLUSION: When screening is offered, clinicians need to have information readily available on test accuracy and the likely result, which is specific to the individual.

Chorionic Gonadotropin↗
PubMed1992

Rectal temperature time of death nomogram: dependence of corrective factors on the body weight under stronger thermic insulation conditions.

Ninety-eight test coolings were made under various cooling conditions (moving air, two types of both clothing and covering) on dummies of real masses of 1, 3.3, 9.9, 24.5 and 33.4 kg, respectively, which cool under standard conditions (unclothed, uncovered, still air) like human bodies of 14, 33, 41, 83 and 104 kg, respectively. The results provide evidence of a non-linear dependence of corrective factors of body weight upon the body weight. The dynamics of the dependence increases with the thickness of thermic insulation. Transferred to the use of the nomogram method on bodies, cooling conditions requiring corrective factors between 0.75 (moving air) and 1.3 (rather thin clothing/covering), known from experience on bodies of an average weight, can be used as in the past, independent of the body weight. According to experience the dependence of corrective factors on the body weight must be taken into account in bodies of a very high or low body weight. For that purpose both a simplified table and a formula for computing is given.

Bedding and Linens↗
PubMed2003

Use of nomograms for predicting survival in patients with castrate prostate cancer.

Given the heterogeneity of prognoses in patients with castrate metastatic prostate cancer, the ability to accurately predict survival is vital for optimal patient counseling, selection of treatments, clinical trial design, and interpretation of clinical data. Over the past 20 years, several prognostic models have been developed in an attempt to refine the clinician's predictive ability. Early models were based on patients with more advanced disease. They included variables that are no longer regularly encountered today and involved cumbersome calculations that were not practical for everyday use in the clinic. Recently, 2 point-based nomograms have been developed based on pretreatment variables measured on a routine basis. These models provide a user-friendly format in which to make sophisticated predictions of survival. These models have improved our ability to predict the outcomes of patients with castrate metastatic disease. However, further work to identify novel prognostic markers to improve the accuracy of these predictions is needed.

Adenocarcinoma↗
PubMed1982

Fetal respiratory movements: a nomogram for fetal thoracic and abdominal respiratory movements.

A nomogram for fetal thoracic and abdominal amplitudes during respiration is presented. The correlation coefficient between the thoracic amplitude and gestational age was 0.973, and that for the abdominal amplitude was 0.920, thus suggesting a strong correlation between gestational age and respiratory amplitude (p less than 0.001), whereas no correlation was found between respiratory amplitude and fetal weight. The respiratory amplitudes were not influenced by intake of meals or time of the day when examination was carried out. The respiratory amplitudes were found to be very reproducible (SEM=0.1 mm, N=42). This new noninvasive method to predict the respiratory distress syndrome seems to be very promising.

Abdomen↗