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At least 55 records · Page 3Linked to original sources
PubMed1979

[Ultrasonic biometry of the fetal crown-rump length between 7 and 20 weeks gestation (author's transl)].

In 370 examinations on 258 patients with known gestational age crown-rump length (CRL) of the fetus was determined by sonar between 7 and 20 weeks. From the results the mean and "2 SD" limits of CRL were derived by means of a non linear regression analysis. The measurements were further analysed to determine gestational age for a given CRL. Besides a velocity curve of CRL growth was calculated. It showed a maximum of 1.8 mm per day at 14 weeks. It was confirmated that sonar measurements of crown-rump length are very useful to estimate maturity of the fetus. The accuracy was found to be best in early measurements (+/-6 days at 7 weeks -+/-11 days at 20 weeks). In regard to clinical decisions reading errors have to be taken into consideration. To avoid them control examinations should be carried out.

Anthropometry↗
PubMed1979

Foetal twin ultrasound biometry.

Biparietal diameter growth differs considerably in the twin gestation compared to the singleton gestation; thus the use of a specific standard is recommended. A shift toward lower values is noticed in monochorial twins. In the case of the abdominal diameter growth, instead, no significant difference is found between twins and singletons.

Cephalometry↗
PubMed1975

[The place of ultrasound diagnosis in obstetrics].

A review is presented of the diagnostic applications of the ultrasonic scan technique in obsterics. In the 1st trimester of pregnancy the demonstration of the gestational sac and of an embryo is most important. During the further course of pregnancy the growth of the gestational sac and motions of the fetus can be observed. A disturbance in the development of the pregnancy can be deduced from these parameters. The various types of abortion can be differentiated by means of the scan. In the 2nd trimester the biometry of the fetus is most important. The motion behaviour of the fetus seems to be a good indicator of its well-being. The location of the placenta and the evidence of twins are easily demonstrable. In the 3rd trimester the biometry of the fetus is a good parameter of its maturity. The diagnosis of the fetal position is important for the management of delivery. Apart from these applications of ultrasound in obstetrics, the procedure is of great value in the diagnosis of tumours and the measurement of the true pelvis in pregnancy.

Abortion, Threatened↗
PubMed1992

Myopia following penetrating keratoplasty for keratoconus.

The frequent occurrence of spherical myopia after penetrating keratoplasty for keratoconus is partly the result of the excessive dioptric power of the grafted cornea which occurs when the diameter selected for the donor button is greater than the diameter of the host incision. This excessive power could be reduced by eliminating disparity between the diameters of the graft and host. To determine what proportion of the myopia in these eyes would persist as a result of axial myopia the axial lengths of 60 patients grafted for keratoconus and 25 emmetropic controls were compared. A keratometry, objective refraction, and contact probe ultrasonic biometry were performed on all eyes. A comparison of the results with a representational schematic eye indicated that the mean spherical refractive error of the grafted keratoconic eyes (-4.83 dioptres) was the combined effect of steepness of the corneal graft (mean radius of curvature 7.46 mm) and an abnormally great axial length (mean 24.84 mm). The increased axial length was mainly the result of elongation of the posterior segment of the globe with a small contribution from an increased anterior chamber depth. Though axial myopia is common in keratoconus, a further study of 70 keratoconic eyes that had not been grafted showed no statistically significant correlation between the posterior segment length and the severity of corneal ectasia. These data suggest that even if excessive corneal power is eliminated after penetrating keratoplasty for keratoconus the associated axial myopia would still produce a mean spherical refractive error of at least -2.8 dioptres.

Adult↗
PubMed1976

[Stages of development and growth of the thyroid gland and adenohypophysis of the dogfish embryo (Scillium canicula Cuv.), a chondrichthyan fish].

The thyroid morphology, histology, biometry and its anatomical connections are studied during the whole embryonic life in the small spotted dogfish (Scyllium canicula Cuv.). The first differentiation of the gland appears as a thickening of the pharyngeal floor, containing PAS inclusions, at stage 10 mm. The first follicles are apparent at stage 30 mm. The thyroid volumetric relative growth is studied during the whole development and is compared with the absolute embryonic length growth. Volumetric variations of the hypophysis upper parts and ventral lobe are also studied during the whole embryonic life.

Animals↗
PubMed1976

Pilocarpine therapy in glaucoma: effects on anterior chamber depth and lens thickness in patients receiving long-term therapy.

The effect of pilocarpine hydrochloride on the anterior chamber depth and lens thickness was measured in 20 eyes of patients with chronic open-angle glucoma who were receiving long-term glaucoma therapy with pilocarpine. Measurements were made with high-resolution ultrasonic biometry. This study demonstrated that regardless of their age (58.4 years, average) and the fact that they had been regularly using pilocarpine from two to four times a day, 85% of these patients demonstrated narrowing of the anterior chamber (AC) depth (average, 0.19 mm) and thickening of the lens (average, 0.21 mm) with each instillation of pilocarpine. In approximately 15% of eyes, a repeatable deepening of the AC depth and flattening of the lens was noted.

Administration, Topical↗
PubMed1976

Interactive editing of biomedical data.

Editing options of an interactive graphical-biometry statistical system are described. A method for screening using a highly reduced data file is illustrated. By utilizing properties of sample Fourier coefficients, the problem of component overlap can be resolved. This, in turn, tends to free edited statistical information from the contamination or truncation inherent in the usual screening process.

Data Display↗
PubMed1992

Correlation of subjective assessment of amniotic fluid with amniotic fluid index.

We assessed the correlation between abnormal amniotic fluid volumes as defined by the two techniques of (1) subjective evaluation and (2) the amniotic fluid index. Ultrasound evaluation of amniotic fluid volume was conducted on 420 pregnant women with known gestational age greater than twenty weeks but less than 42 weeks. Amniotic fluid was evaluated subjectively and placed into one of three categories: normal, oligohydramnios or polyhydramnios. After fetal biometry was performed, the amniotic fluid volume was assessed semi-quantitatively by the amniotic fluid index technique and assigned to similar categories. We analyzed the data with 2 x 2 contingency tables, using amniotic fluid index as the 'gold standard test'. Our study demonstrates that there was moderate agreement (kappa.5) between both amniotic fluid techniques in the identification of oligohydramnios. However, agreement between the techniques was poor for the identification of polyhydramnios (kappa.16).

Amniotic Fluid↗
PubMed1975

The emmetropic and the iseikonic implant lens: computer calculation of the refractive power and its accuracy.

The preoperative calculation of the power of a lens prosthesis and the resulting aniseikonia is given, as well as diagrams for reading the emmetropizing and the iseikonizing power of the lens. The consequences of an inaccuracy in the measurement of the dimensional and refractive properties of the eyes are calculated. It can be concluded that the main determinant for an accurate prediction of the power of the intraocular lens prosthesis is the axial length measurement. Since this measurement is carried out by means of ultrasound biometry, it is necessary to emphasize the adequate application of this technique. The problem as to whether an emmetropizing, or an iseikonizing lens should be implanted may be solved with the data supplied by the computer program. A flow chart for this program is given in an appendix.

Anterior Chamber↗
PubMedDate not supplied

The WHO multinational study of vascular disease in diabetes: 2. Macrovascular disease prevalence.

14 national groups have collaborated under WHO auspices to select, from local defined populations of individuals with clinical diabetes, groups of approximately 500 within the age range 35--55 yr stratified by age, sex, and known duration of diabetes. In each center, the selected patients were submitted to a standardized study protocol, which included systematic inquiry (WHO questionnaire) for the presence of symptoms of angina pectoris, history of myocardial infarction, presence of intermittent claudication, and cigarette smoking history. Examination included standard biometry, blood pressure measurement, 12-lead (centrally Minnesota coded) electrocardiography, and central laboratory measurement of serum cholesterol and creatine. Ophthalmoscopic and urinary examinations were also included. The prevalence of arterial disease symptoms and electrocardiographic abnormalities show very large variation between countries, the lowest rates generally being found in the Oriental samples and the highest in the European. "Risk factors" for arterial disease (blood pressure, serum cholesterol, and cigarette smoking) also vary widely between diabetic groups. Although data are not yet complete, these differences appear unlikely to explain the variation in the atherosclerotic morbidity observed. Diabetic women were at least as vulnerable to arterial disease as diabetic men. A high prevalence of nonspecific abnormalities of the repolarization phase of the ECG was found, even in groups where ischemic abnormalities were rare. The origin of these is uncertain; they may represent variable local changes or possibly diabetic cardiomyopathy. This preliminary report confirms and quantifies previous indications that the impact of atherosclerotic disease on persons with diabetes varies considerably between national groups, in broad terms, running parallel with the variations in prevalence in the populations in general and suggesting that cultural and/or ethnic factors are more important determinants of atherosclerosis in diabetic individuals than is the diabetic state per se.

Adult↗
PubMed1992

Autosomal dominant congenital miosis with megalocornea.

A family with AD congenital miosis is presented. The ocular symptoms were: megalocornea, iris translucency, microcoria with poor pupillary dilatation and goniodysgenesis with anterior insertion of the iris. This observation confirms that in congenital miosis abnormal development of the whole anterior eye segment may occur. The patients have an increased risk to develop glaucoma. If retinoscopy is impossible due to pin-point pupils, ultrasonic biometry to determine the axial length is recommended. An optical iridectomy could improve visual performance at low illumination; the complaints of photophobia, which are related to the iris translucency, persist.

Adolescent↗