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At least 181 records · Page 10Linked to original sources

Clinical comparison of automated and manual keratometry in pre-operative ocular biometry.

Corneal measurements, using the manual (Topcon OM-4) and automated (Canon RK-1) keratometers was performed on 104 eyes of 104 patients undergoing cataract and implant surgery to assess the role of automated keratometry in pre-operative ocular biometry. Four eyes of four patients were excluded from statistical analyses for various reasons. The time taken to perform automated keratometry was a mean of 61 (SD 21) seconds compared to 205 (SD 37) seconds for manual keratometry; the difference was statistically significant (p < 0.001). In terms of the various keratometry values compared, mean K (corneal refractive power), flattest K, steepest K, astigmatism and the axis of astigmatism, 65% to 75% of the cases on automated keratometry were within 0.26 dioptres or 11 degrees of manually determined values; the difference was statistically significant (p < 0.001). Although automated keratometry was significantly quicker than manual keratometry, we continue to use manual keratometry values for intraocular lens power calculations as the accuracy demonstrated by automated keratometry was considered inadequate for this purpose.

Aged↗

Ocular biometry in pre-term infants without retinopathy of prematurity.

Serial ocular A-scan ultrasound biometry was performed on 100 pre-term infants (less than 32 weeks gestation and/or less than 1500 g) who did not show features of retinopathy of prematurity (ROP) during a screening programme. Axial length increased from 15.38 +/- 0.25 mm at 33 weeks post-menstrual age to 16.88 +/- 0.59 mm at 41 weeks (rate of growth 0.18 mm/week, r = 0.99). The rate of growth appeared to slow down after 40 weeks (term) to 3 months post-term. Male infants had longer eyes and a greater rate of growth than female infants. Axial length (AL) was significantly correlated with birth weight, biparietal and occipito-frontal diameter in the weeks after birth. Between weeks 33 and 41, the anterior chamber depth (ACD) increased from 1.92 +/- 0.13 mm to 2.43 +/- 0.18 mm, and lens thickness (LT) increased from 3.82 +/- 0.33 mm to 3.90 +/- 0.13 mm. The largest percentage growth between weeks 33 and 41 occurred in ACD (22%), followed by vitreal length (10%), AL (9%) and LT (2%). These data will help in future studies on the role which ROP plays in the development of ocular growth.

Anthropometry↗

Clinical interpretation of ultrasound biometry for dating and for assessment of fetal growth using a wheel and chart: is it sufficiently accurate?

OBJECTIVES: To investigate how accurately practicing obstetricians (experts) can apply dating rules and compare the interpretation of gestation-sensitive ultrasound data with those of a computer system. SUBJECTS: Seventeen practicing obstetricians. Members of the Royal College of Obstetricians and Gynaecologists, from 14 different units throughout the UK. DESIGN: Six cases with menstrual and ultrasound data together with identical ultrasound charts and obstetric wheels. MAIN OUTCOME MEASURES: Concordance between the calculated estimated date of delivery (EDD) and growth assessment provided by the experts and the computer system. RESULTS: The calculation of the EDD by the experts was imprecise (59% within 3 days overall). Concordance with the computer calculation was poorest when the ultrasound measurements lay close to the upper or lower centile lines (average 7% within 3 days of the computer). Interpretation of growth showed good concordance with the computer when gestation was not critical to the interpretation (94%), but very poor when gestation was critical (7%). CONCLUSIONS: Calculation of EDD by means of an obstetric wheel and charts is not precise. Compared with the computer system, these errors have a significant effect on the subsequent interpretation of growth scans when the data are borderline. A computer system provides the more accurate method for interpreting gestation-sensitive ultrasound biometry.

Anthropometry↗

Simultaneous measurements of refraction and A-scan biometry during accommodation in humans.

PURPOSE: Accommodation is a dioptric change in power of the crystalline lens resulting from ciliary muscle contraction that leads to an increase in lens surface curvatures and thickness and changes in the position of lens surfaces. Previous studies have used A-scan ultrasound to measure changes in the position of lens surfaces with voluntary accommodation, but have not simultaneously measured the change in refraction. The goal of this study is to simultaneously measure and correlate refractive and biometric changes in the lens during voluntary accommodation in humans. METHODS: Refraction was measured off-axis in the right eye and biometry on-axis in the left eye simultaneously during voluntary accommodation in 22 human subjects between the ages of 21 and 30 years (mean +/- standard deviation: 25.8 +/- 2.3 years). Subjects viewed a distant target and four near targets spanning the full accommodative range available to evaluate refraction and lens surface position at each accommodative state. RESULTS: Maximum objectively measured accommodative amplitude of all subjects was 5.64 +/- 0.21 D (mean +/- standard error of mean). Biometric and refractive changes during accommodation were linearly correlated. The mean +/- standard error of mean decrease in anterior chamber depth was 0.051 +/- 0.008 mm/D, increase in lens thickness was 0.067 +/- 0.008 mm/D, and increase in anterior segment length was 0.017 +/- 0.005 mm/D during accommodation. There was a net anterior movement of the lens center of 0.017 +/- 0.005 mm/D. CONCLUSION: Anterior chamber depth, lens thickness, and anterior segment length change linearly with refraction during accommodation. Per-diopter changes in the lens were greater in the current study compared with previous studies in which only accommodative demand was measured, which overestimates the accommodative response.

Accommodation, Ocular↗

[Fetal ultrasound biometry and amniotic fluid insulin concentration in pregnant diabetic patients].

OBJECTIVE: The aim of the study was to prove the sensitivity of sonographic measurements for the presence of a fetal hyperinsulinism. METHODS: In a longitudinal examination of 102 insulin-dependent diabetics we show the correlation between the amniotic fluid insulin level and the biparietal diameter, abdominal diameter and femur length in the third trimester. The control of the maternal metabolic state was done by measuring the glycosylated hemoglobin and fructosamine at the time of the amniocentesis. RESULTS: The sensitivity, specificity, positive and negative predictive value of sonographic measurements > 75th percentile in fetal hyperinsulinism was for the biparietal diameter 21, 96, 81 and 62%, for the abdominal diameter 48, 82, 69 und 66%, and for the femur length 22, 90, 67 and 57%. The maternal glycoproteins did not show any correlation with the amniotic fluid insulin level. CONCLUSIONS: The results demonstrate that fetal hyperinsulinism cannot be proved by fetal biometry or evaluation of the maternal metabolic state.

Adult↗

Public Health Service--Privacy Act of 1974. Notification of new system of records: "clinical research; records of subjects in intramural research, epidemiology, demography, and biometry studies on aging.".

In accordance with the requirements of the Privacy Act, the Public Health Service (PHS) is publishing notice of a proposal to adopt a new system of records. "Clinical Research: Records of Subjects in Intramural Research, Epidemiology, Demography, and Biometry Studies on Aging." DHHS/NIH/NIA, 09-25-0142. These records will be used to accomplish scientific research conducted by intramural scientists employed by the National Institute on Aging (NIA), and by hospitals, universities, research centers and research foundation under contract with NIA. These research activities aim at determining the health status of individuals and changes in health status over time, the incidence and prevalence of certain diseases and problems of the aged in certain populations, and changes that take place as the individuals age who are under study.

Aging↗

Charts of Thai fetal biometries: 2. Biparietal diameter.

A cross-sectional study was conducted in order to construct a new reference chart for Thai fetal biparietal diameter (BPD). A total of 621 normal pregnant women between 12-41 weeks of gestation and their fetuses were recruited. Measurements were made once at a randomly assigned gestational age specifically for the purpose of this study only. Due to unfavorable fetal position in some cases, BPD data were available in 613 measurements. Linear regression models were fitted separately to estimate the mean and standard deviation as functions of gestational age. Reference centiles were constructed from both equations, assuming the data were normally distributed. A new reference centiles chart for BPD is presented and compared with previously published data. Our derived centiles were clearly lower than those from Western studies showing the importance of racial differences between populations. This elucidates the need to develop fetal biometries charts specifically for each region.

Anthropometry↗

[Biometry and structure of the left internal thoracic and radial coronary arteries].

In an attempt to elucidate the causes of occlusion of radial arteries for coronary artery bypass grafts, we studied the biometry and histology of the coronary, radial and left internal thoracic arteries of 20 anatomical subjects (13 males and 7 females). These specimens were calibrated to the various bypass graft sites using coronary calibrators, and were then submitted to histological examination to determine the structure of the vessel wall. Our preliminary results show no correlation between the internal calibres of these various arteries. Like the coronary arteries and their branches, the radial artery is a muscular artery. In contrast, the left internal thoracic artery like the aorta, is an elastic artery.

Aged↗

Recommendations of the German Association for Medical Informatics, Biometry and Epidemiology for education and training in medical informatics.

In the fields of health care and medicine there is an immense demand for a systematic application of methods of information processing and for the use of computers. Obviously, to that end well-trained scientists and qualified personnel must be available. With the present recommendations on education and training in medical informatics the German Association for Medical Informatics, Biometry and Epidemiology (GMDS) proposes structure and contents of medical informatics curricula and courses. The recommendations describe a 2-dimensional educational framework with different education levels in one dimension and various types of educational needs and orientation in the other one. The recommendations comprise at the university level education as well specialized curricula covering the total spectrum of medical informatics as well as informatics curricula with medical informatics as integrated applied subject or subsidiary subject, respectively. Besides these informatics-oriented approaches medical-oriented programs of education in medical informatics are recommended, e.g., post-graduate education in medical informatics for physicians based on foundations in medical informatics as part of their initial training in medicine. At the level of polytechnical schools curricula of medical documentation and informatics and at the level of professional schools training in medical documentation are recommended. This report is a translation of its German original. Although considered by the GMDS as recommendations for the Federal Republic of Germany, the text may also contribute to the development of an international, especially European framework of training in medical informatics.

Germany↗

[Sonographic biometry of fetal organs].

Over a period of 18 months measurements of fetal Organs (cornu anterius of the lateral ventricle, medium diameter of the four-chamber-view of the heart, transverse diameter of lungs, stomach, gall bladder, colon and urinary bladder) were carried out in a population of 223 normal pregnancies. The measurements were correlated to the age of pregnancy and sonographic growth parameters (biparietal diameter--BPD, mean cephalic diameter--MCD, mean abdominal diameter--MAD). The results show different growth velocities of the particular organs, obviously depending on physiological function. The variability is increasing with fetal growth. We found no fundamental difference as far as correlation of organ measurements to age of pregnancy, to BPD, MCD or MAD. In summary the imaging and biometries of the fetal organs appear to be possible in relatively little time and such is a valuable method for the detection of fetal anomalies.

Cerebral Ventricles↗

[Biometry of the inferior vena cava (subrenal segment): dissection of 100 recently deceased subjects].

The vena cava inferior in its infra-renal part is a selective place to set on anti-thrombosis devices. The biometry of 100 fresh, adult cadavers interested the useful and real lengths, the diameters on several levels and on the corresponding part of the aorta, the end of the iliac venae and the origin of the iliac arteriae . The useful length of the vena cava inferior is 96 mm in mean, and its real diameter is 17 mm, on the middle of the infra-renal part.

Adolescent↗

[Fetal cardiac biometry. Evaluation of the growth of the right and left ventricles using bidimensional echocardiography in normal pregnancies].

Two-dimensional echography makes it possible to study the fetal heart in a routine obstetrical setting. It is easy to see the four cavities of the heart from the long axis. The speed of growth of the internal diameters of the right and left ventricles have been studied at different stages of normal pregnancy. In this way it has been possible to show the morphometric equilibrium between the right and the left side at different stages of the pregnancy by cardiac ventricular biometry. These measurement are the first step in screening for intra-uterine cardiac abnormalities.

Echocardiography↗

[Biometry, hematology, plasma biochemistry and plasma and tissues enzymology of the red partridge (Alectoris rufa) (author's transl].

The following parameters have been estimated in 15 red partridges (young adults of both sexes): 1. Biometry: relative weight of 10 organs (liver, kidneys, heart, brain, spleen, lungs, small gut, coecum, stomach, gizzard). 2. Hematology (mean +/- S.D.): Erythrocytes, 3.4 X 10(6) +/- 0.3 X 10(6) cells/mm3; packed cell volume 0.46 +/- 0.17; haemoglobin 103 +/- 27 g/l; mean red blood cell volume, 135.6 +/- 10.4 micrometer3; haemoglobin per red blood cell, 32.2 +/- 5,2 pg; haemoglobin concentration in red blood cells, 24.0 +/- 2.9 %; leukocytes, 36.9 X 10(3) +/- 7.8 X 10(3) cells/mm3; heterophilic, 32.3 +/- 8.3 %; basophilic, 5.3 +/- 1.5 %; eosinophilic, 1.4 +/- 1.5 %; lymphocytes, 56.1 +/- 7.3 %; monocytes, 4.6 +/- 1.4 %. 3. Blood biochemistry: Na +, 155 +/- 6 mEq/l; K +, 6.5 +/- 1.2 MEq/l; Cl--, 107 +/- 4 mEq/l; Pi, 53.3 +/- 14.4 mg/l; urea, 0.19 +/- 0.05 g/l; uric acid, 33.2 +/- mg/l; creatinin, 14.7 +/- 0.9 mg/l; glucose, 2.77 +/- 0.35 g/l; cholesterol, 1.38 +/- 0.36 g/l; total proteins, 44.1 +/- 5.9 g/l; albumin, 50.0 +/- 8.7 %; alpha globulins, 3.9 +/- 1.5 %; beta globulins, 7.5 +/- 2.2 %; gamma1 globulins, 31.5 +/- 5.6 %; gamma2 globulins 8.0 +/- 3.5 %. 4. Serum enzymology: Alkaline phosphatase, 8177 +/- 5078 u/l; SGOT, 356 +/- 138 u/l; SGTP 28.3 +/- 12.5 m/l; LDH, 955 +/- 570 m/l; GLD 12.6 +/- 12.4 u/l; CPD, 136 +/- 77 u/l; choline esterase, 2181 +/- 506 u/l. 5. Tissue enzymology: the 7 preceding enzymes have been estimated in 10 tissues listed in 1.

Alkaline Phosphatase↗

Computed-tomographical biometry of the cervical spine on horizontal cross-sections every 6 mm.

Biometry was performed on the computed tomographical cross-sections of one human cervical spine. The entire spine was removed with the head and neck from a fresh cadaver of an adult man. Horizontal cross-sections were performed with a C. T. scan from the base of the skull to the thoracic level. The measurements concerned the diameters of the vertebrae, spinal canal and spinal cord; the depth of the posterior and anterior walls, and of the para-vertebral muscles. Clinical and fundamental applications are underlined.

Aged↗

[Biometry of the thoracic spine using scanography].

Biometry was performed on CT scan of a human thoracic spine. The entire spine was removed from the fresh corpse of an adult man. Horizontal cross-sections were performed, every 6 mm from C7 to L1. Measurements involved the main diameters of the vertebrae, spinal canal and spinal cord, muscular depth and punctures. Several density measurements were noted.

Aged↗

[Biometry of the lumbar spine using scanography].

Biometry of one human lumbar spine was performed on a series of computed tomographic cross-sections every six millimetres. Linear and density measurements were multiplied on each level. Biometrical results confirm date of the litterature, but are more numerous by means of CT scan. Effectiveness on the living is acquired by whole body apparatus.

Anthropometry↗

[Ocular biometry in neonates (author's transl)].

Ocular biometry tests were conducted in approximately 100 full-term neonates (of both sexes) during the first five days following birth. Measured parameters included the dimensions and shape of the ocular globe, and optic component refractions. For the first time, individual values were determined for the corneal curvature radius, corneal refraction, and the transverse diameter and shape of the globe. Results are analyzed statistically, and the most important correlations calculated.

Anthropometry↗

[Biometry of the cervical spine using tomodensitometry].

Biometry was performed on the computed tomographical cross-sections of one human cervical spine. The entire spine was removed with the head and neck from a fresh cadaver of an adult man. Horizontal cross-sections were performed with a C.T. scan from the base of the skull to the thoracic level. The measurements concerned the diameters of the vertebrae, spinal canal and spinal cord: the density of the posterior and anterior walls, and of the para-vertebral muscles. Clinical and fundamental applications are underlined.

Aged↗