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PubMed1999

An index for human lens transparency related to age and lens layer: comparison between normal volunteers and diabetic patients with still clear lenses.

OBJECTIVE: The light scattering intensity of normal, clear lenses varies with age and with the localization within the lens. Realizing the biometry of single lens areas together with their relevant light scattering intensity one should be able to calculate an index to express the lens transparency properties of normal human lenses in dependence on age. Performing the same procedure in cases of diabetic patients with still clear lenses it should become possible to obtain an index for the lens transparency properties of lenses under the 'risk factor' diabetes. METHODS: 748 eyes with transparent lenses in 383 healthy individuals and 134 eyes with clear lenses in 70 subjects with diabetes were examined. Scheimpflug slit images of the lens were documented by a Nidek EAS-1000 instrument. Biometry for measuring the distance of the single lens layers from the anterior capsule and densitometry for determining the light scattering intensity of six defined lens layers along the (theoretical) optical axis were performed. The index of the lens transparency properties was calculated using the light scattering intensity of a defined lens layer and its distance from the anterior capsule. RESULTS: Lens thickness and light scattering intensities increased linearly with increasing age in the normal population as well as in the diabetic patients. The densitogram pattern of the light scattering intensities in the defined representative six points was similar in both populations, but in the diabetic group the lens thickness was larger and the light scattering intensities were higher at all ages. CONCLUSION: The index of lens transparency properties calculated with the light scattering intensities of a certain lens area and its distance from the anterior capsule is a useful measure of lens clarity in dependence on age. 'Clear' lenses of the diabetic population show significantly higher indices for the lens transparency properties in all age groups.

Adult↗

PubMed1982

Evaluation of various monitoring techniques in late pregnancy to detect poor intrauterine fetal growth.

102 pregnant women, suspected of placental insufficiency, according to their physical findings, were regularly monitored by various techniques which were related to the birth of a small-for-date infant (less than 10th weight percentile), and assessed by calculations of recognition, occurrence, and exclusion probabilities. High reliability was given by ultrasonic biometry, by human placental lactogen (HPL) and estriol both in serum, and placental perfusion measurements (113mIn) if they were within the normal range. Antepartum non-stressed cardiotocogram revealed probability rates similar to HPL in serum. Combination of monitoring methods augmented the prognostic value, nevertheless a problem of relatively high numbers of false-positive findings remained. For large departments all methods are recommended; for smaller ones particularly antepartum cardiotocogram in combination with ultrasonic biometry is recommended.

Electrocardiography↗

PubMed1999

Twin-to-twin transfusion syndrome: a case report. Antepartum prediction of underlying placental vascular pattern in monochorionic twin pregnancies may be possible.

A case of twin-to-twin transfusion syndrome is described. Comparing data of serial antepartum ultrasonography with a haemodynamic model suggests the possibility of predicting the underlying placental vascular anatomy. It is suggested that serial ultrasonography, including full biometry, pulsatility indices of the umbilical arteries, foetal echocardiography, assessment of amniotic fluid indices and foetal bladder filling could serve as ultrasound parameters for pattern recognition of the underlying placental vascular anomaly. Biometry should be plotted serially in a difference/average plot. Future application of such intensive ultrasound monitoring in monochorionic twins, as soon as monochorionicity is established, may distinguish those monochorionic twins who may benefit from treatment from those whom it would be better only to observe.

Adult↗

PubMed2006

Contact lens wear and IOL power calculation before cataract surgery: a cautionary tale.

PURPOSE: To present a case of erroneous corneal measurements, which led to inaccurate predicted intraocular lens (IOL) power. METHODS: A 60-year-old woman underwent preoperative assessment for cataract surgery. The predicted IOL power was 19.5 D. RESULTS: Repeated biometry led to different measurements and an 11.0-D powered IOL was inserted. The predicted IOL power was incorrect, as the patient had worn contact lenses during the preoperative assessment. CONCLUSIONS: This case demonstrates that errors can occur, and it is essential to fully understand the principles of biometry and the refractive issues of cataract surgery to avoid postoperative refractive errors.

Cataract Extraction↗

PubMed2000

Management of pregnancies with suspected intrauterine growth retardation in Sweden. Results of a questionnaire.

BACKGROUND: Diagnosis and management of intrauterine growth retardation during pregnancy remain a major challenge in obstetric care. The objective of this survey was to evaluate the routine clinical management of pregnancies with suspected intrauterine growth retardation at obstetric departments in Sweden. METHODS: In 1997, a questionnaire was sent to all 59 obstetric departments in Sweden. Forty-two departments, caring for 83% of all deliveries in Sweden, replied. Four major topics were addressed: definition and diagnosis of intrauterine growth retardation; magnitude of the problem; clinical management; use of Doppler ultrasound in clinical decision-making. RESULTS: Intrauterine growth retardation is diagnosed by a combination of serial fundal height measurements and ultrasonic fetal biometry at 40 departments, two departments perform routine fetal biometry at 32 weeks. The diagnosis is most often made at 32-36 gestational weeks. Five departments use 1.5 s.d. below the mean as cut-off point for diagnosis of small for gestational age fetuses; 35 departments use mean - 2 s.d. and two departments mean - 2.5 s.d. Intrauterine growth retardation is suspected in 1.6-6.3% pregnancies. About 19% of patients with suspected intrauterine growth retardation are hospitalized. On average, 63% of all small-for-gestational age babies are diagnosed prenatally. Thirty-nine out of 42 obstetric departments use formalized management protocols. All departments use cardiotocography, repeat ultrasound scans and Doppler ultrasound for antenatal surveillance. CONCLUSIONS: In Swedish obstetric units, the diagnostic procedures and methods of fetal surveillance in pregnancies suspected of intrauterine growth retardation are more or less uniform. Doppler examination of umbilical artery is used at all responding departments and is considered a valuable asset in clinical decision-making.

Cardiotocography↗

PubMed2000

[The measurement of normal values of exophthalmos, interpupillary distance and interorbital distance of children and adolescence in Xiamen and the rule of their development].

OBJECTIVE: To investigate the developing rhythm of children and adolescent exophthalmos, interorbital distance (IOD) and interpupillary distance (IPD) and their mutual relationships. The study will provide biometry data for formulating juvenile criteria of correcting spectacles. METHODS: Random sampling was performed among children and adolescence aged 5 - 17 years in Xiamen. Adopting epidemic survey, we measured the biometry values of IOD, IPD and exophthalmos with a sliding gauge and exophthalmometer. RESULTS: The average value of exophthalmos was (14.48 +/- 1.71) mm. For the 5 - 8 years old children, the value of exophthalmos trended to increase with the increase of age, meanwhile the value of exophthalmos of adolescence aged 9 - 17 years old tended to be stabilized. The average value of IOD was (95.55 +/- 5.32) mm and the average value of IPD was (56.99 +/- 3.93) mm. Both the values of the IOD and IPD of the male were higher than that of the female. The results of the IOD and IDP distance increased with the increase of age and it trended to be periodic. There was positive correlation between the development of IOD and that of IPD, and it could be described by a linear equation. CONCLUSIONS: There is only one rush-increase stage of ocular development which is before the 8 years old in children. The rule of its development is in accordance with the growing and developing mode of neurological system.

Adolescent↗

PubMed2002

Postpartum X-ray pelvimetry. Its use in calculating the fetal-pelvic index and predicting fetal-pelvic disproportion.

OBJECTIVE: To determine whether postpartum x-ray pelvimetry can be used to calculate the fetal-pelvic index (FPI) in future pregnancies. STUDY DESIGN: In stage I of the study, 10 gravid women, after 36 completed weeks' gestation, underwent x-ray pelvimetry before delivery. Pelvimetry was repeated within two days after delivery. Comparisons between antepartum and postpartum measurements were made using paired t tests and correlation coefficients. In stage II, 25 gravid women, after 36 completed weeks' gestation, underwent fetal ultrasound for biometry. X-ray pelvimetry was performed within two days after delivery. FPI was calculated for each pregnancy using antepartum fetal ultrasound and postpartum pelvimetry measurements. FPI calculations were correlated with the incidence of fetal-pelvic disproportion (FPD), as indicated by the requirement for cesarean section for arrest of active labor. Sensitivity, specificity and predictive value of FPI were assessed. RESULTS: In stage I, mean anteroposterior and transverse diameters of the pelvic inlet, midpelvis and pelvic outlet did not differ significantly. In stage II, the sensitivity of FPI for detecting FPD was 100%, specificity 95%, positive predictive value 80%, and negative predictive value 100%. CONCLUSION: Postpartum pelvimetry has the same association with FPD as antepartum pelvimetry. The strategy of using postpartum pelvimetry and antepartum fetal biometry to calculate FPI successfully identified 100% of the patients who ultimately required cesarean section for FPD, with a false positive rate of 5%. Pelvimetry performed postpartum in an index pregnancy may be used in future pregnancies, in combination with antepartum fetal ultrasound, to calculate FPI and predict the likelihood of FPD.

Adult↗

PubMed2003

Maternal serum activin A levels in association with intrauterine fetal growth restriction.

OBJECTIVE: To assess maternal serum activin A as a potential marker of fetal growth restriction. DESIGN: A cohort study. SETTING: A maternal-fetal medicine unit, university teaching hospital. POPULATION: Fifty-seven women with a small fetus (less than 10th centile for gestation) referred for assessment of fetal size by ultrasound biometry. METHODS: At the time of presentation for fetal biometry, maternal blood was collected for activin A measurement. The case records of each woman were independently reviewed after delivery and the pregnancy grouped into one of three groups: constitutionally small fetus, intrauterine growth restricted (IUGR) fetus or IUGR fetus and maternal pre-eclampsia (IUGR-pre-eclampsia). Activin A levels in the three groups were compared. MAIN OUTCOME MEASURES: Maternal serum activin A levels. RESULTS: Sixteen of the 57 pregnancies were classified as constitutionally small, 17 as IUGR and 24 as IUGR-pre-eclampsia. Expressed as multiples of a normal median (MoMs), the median (95% CI) activin A level in the constitutionally small pregnancies was 1.12 (0.72-1.39) MoMs significantly lower than the level in both the IUGR pregnancies, 3.00 (1.84-4.11) MoMs, and the IUGR-pre-eclampsia pregnancies, 7.96 (5.73-10.62) MoMs (P = 0.002 and 0.0001 for IUGR vs constitutionally small and IUGR-pre-eclampsia vs constitutionally small, respectively). CONCLUSIONS: Maternal serum activin A may be useful in the assessment of the small for gestational age fetus.

Activins↗

PubMed2003

[Triplet pregnancy complicated by intrauterine death of two fetuses--case report].

INTRODUCTION: Multiple pregnancy still constitutes a difficult therapeutic problem in perinatology. The incidence of this phenomenon describes Hellin's formula: the number of twin pregnancy is 1/n, triplet--1/n 2 etc. Among complications observed in multiple pregnancy intrauterine death of one or more foetuses is not rare. Due to progressive disturbances in haemostasis the risk for a mother and remaining live foetus increases with gestation. The aim of this paper was to present a case report of triplet pregnancy complicated by an intrauterine death of two foetuses. REPORT: 33 years old patient was diagnosed by ultrasound in the 19th week of her second gestation (1 child) a triplet pregnancy. Three live foetuses were seen then with biometry of about 14/15 gestational week There was one joint placenta on the back uterine wall and two children were sharing an amniotic sac. On the consecutive ultrasound examination the three foetuses were alive, but only one had a biometry for 21st week, two--were slowing down having measurements adequate for 19/20th week. After four weeks on usg the death of two siblings was confirmed (age 19/20 gestational week). One remaining live foetus was according to usg 24 weeks old. The patient was transferred to the II Dept. Even though no disturbances in coagulation were observed, low molecule heparin prophylaxis was introduced. During hospital stay a gestational diabetes was diagnosed well corrected by diet only. Coagulation parameters as well as infection indexes were regularly monitored. The foetal well-being was established by non-stress test, biophysical profile and Doppler vascular flows. After 39 days of hospitalisation an elevation of fibrin degradation products (FDP) was noted so the dosage of low molecule heparin was immediately increased to the therapeutic values. In spite of that FDP still were growing. It was decided to introduce a steroids treatment to accelerate the maturity of foetal lungs. In the 31st week according to usg, after PROM, the emergency caesarean section was performed. Daughter, breech presentation, weighting 1380 grams was born, with Apgar score 6-8-8. At the beginning artificial ventilation was necessary. After 11 days thanks to gradual improvement transfer from NICU to prematurity ward was possible. The postoperative period was uneventful and a mother was discharged home on the 7th day. CONCLUSION: Careful monitoring of a survived foetus as well as coagulation system has allowed to extend the duration of pregnancy for further 45 days and to deliver an infant capable to live.

Anticoagulants↗

PubMed2004

[Sucessful pregnancy outcome following three severe placental abruptions and intrauterine fetal death in the patient--heterozygous carrier of R506Q mutation of factor V (Leiden)].

A case of successful pregnancy outcome is reported in a patient with 3 preceding severe placental abruptions with intrauterine fetal death and caesarean deliveries. In the course of the current pregnancy heterozygosity for R506Q mutation of factor V (Leiden) was diagnosed in 26 weeks of gestation [w.g.] and low molecular weight heparin [LMWH] therapy initiated. Maternal condition was stable until delivery and all laboratory findings were within normal range. The fetus was followed up by ultrasound biometry and Doppler blood flow studies. From 28 w.g. on NST and biophysical profile were included. An emergency caesarean section was performed in 34 w.g. because of contractions not responding to tocolysis. The newborn was in good condition with weight and length corresponding to the 10th centile for gestational age [g.a]. Histologic study of the placenta showed anemic infarctions and recent haemorrhages in the basal and the chorionic plate. The initiation of LMWH therapy in the case reported was late (26 w.g.). By that moment there was already evidence of impaired fetal growth with fetal biometry corresponding to the 10th centile for g.a. After LMWH therapy was started no further slow down of fetal growth was registered. Successful pregnancy outcome may be related not only to LMWH therapy but also to other factors like active fetal monitoring after 28 w.g. and the emergency caesarian delivery immediately after the onset of uterine contractions. Patients with past obstetric history of severe preeclampsia, placental abruption or fetal growth restriction have to be screened for hereditary or acquired thrombophilia. If a thrombophillic state is present early LMWH therapy has to be considered. It is aimed to prevent anaemic placental infarctions and thrombotic complications.

Abruptio Placentae↗

PubMed2005

[Axial length of the ocular globe and hypotensive effect in glaucoma therapy with prostaglandin analogs].

PURPOSE: To observe the possible correlations between the hypotensive effect of the prostaglandin analogs and the axial length of the ocular globe. METHOD: A prospective, observational and randomized study (one year) on 27 patients with POAG treated by prostaglandin analogs monotherapy. The patients have been divided in two groups according to the type of the prostaglandin analogs used: group A - 12 patients - travoprost 0,004 % (Travatan) and group B - 15 patients - latanoprost 0,005 % (Xalatan). The IOP and the axial length have been evaluated at the beginning of the study and at 1, 3, 6, 9, 12 months using Goldmann aplanotonometry and echo-biometry. The results have been statistically analyzed using the Wilcoxon test. RESULTS: The mean IOP reduction was similar in both groups, without statistically significant differences. Between the IOP reductions and the axial length of the ocular globe were demonstrated significant correlations according to the patients distribution on the echo-biometry results. CONCLUSIONS: The IOP reduction with prostaglandin analogs monotherapy may also depend of the axial length of the ocular globe.

Antihypertensive Agents↗

PubMedDate not supplied

[Ultrasonics in the diagnosis and staging of endometrial carcinoma].

In the study of endometrial pathology actually ultrasounds have a few utility in precocious diagnosis, but can be useful during the staging phase (echo-histopathologic correlations, tumor biometry, myometrial invasion). Present study is relative to 134 patients affected by endometrial carcinoma (histologically proved) and preliminarily submitted to echotomography. The "false negative" results of ultrasounds were 16/134. Echographic observations, classified according to Niwa e coll. and Obata, were put in comparison with anatomo-histopathology. The evaluations of tumor dimensions and myometrial invasion were correct respectively in 59.2% of cases and in 64.1% of cases. During the staging phase of endometrial neoplasia echotomography can allow a better pre-surgical definition, mainly with a more detailed informations about tumor biometry (T) and myometrial invasion (M).

Aged↗

PubMed1990

[Biochemical aspects of the evaluation of fixed drug combinations].

Various disciplines have to contribute to the general problem of the evaluation of fixed dose combination drugs, as for instance (clinical) pharmacology, biometry, scientific drug regulations and public health officials. The EC guideline 75/318/EWG and its eludications as well as the German "Arzneimittelprüfrichtlinien" of Dec. 14, 1989 (as referred to in the "Arzneimittelgesetz" of 1986) required that such issues concerning fixed dosage combination drugs must be considered and taken into account. In this framework it is the responsibility of biometry to both to guarantee the use of a valid study design to assure interpretation of the results and to quantify the reliability of pharmacological and clinical considerations. The following paper is concerned with biometrical aspects of the combination drug problem. Basic considerations from a clinical or a pharmacological point of view with respect to the question of whether fixed combination drugs are reasonable or not are not discussed. To support the use of combinations of drugs, a central argument is the improvement of the benefit risk relation compared with that of an adequate monotherapy. Beyond this the fixed combination drugs require additional arguments regarding the enhencement of the safety or the simplicity of the therapy fixing the ratio. It follows that fixed combination drugs have to be supported twice, first with respect to the combination itself, and second with respect to the fixed mixing ratio of its components. The biometrical aspects of the assessment of the gains from (fixed) drug combinations are related to the kind of benefit/risk improvement that is expected. In the first section we discuss some possible types of benefit and risk.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗

PubMed1989

A combined historic and sonographic score for the detection of intrauterine growth retardation.

Sonographic analysis of fetal biometry has been useful in the antepartum detection of intrauterine growth retardation (IUGR). Little attention, however, has been focused upon elements of the maternal and fetal history that may significantly affect the likelihood of IUGR. To define more precisely both the clinical and sonographic parameters associated with IUGR, we studied the following variables: routine fetal biometry (biparietal diameter, head circumference, abdominal circumference, and femur length), fetal weight percentile, amniotic fluid volume, and an antenatal scoring system for IUGR. One hundred one consecutive fetuses with an estimated fetal weight at or below the tenth percentile for gestational age formed the study population. The results of multiple logistic regression analysis indicated that weight percentile was the single most important sonographic parameter in the detection of IUGR. Maternal history and femur length were also found to be important independent predictors of IUGR.

Birth Weight↗

PubMed1983

Lens power calculation--is it necessary?

In a group of 70 patients from whom myopes were not excluded, 90 per cent resulted in postoperative refraction between -1.75 and +0.75 when the power of implant was calculated using A Scan biometry. Sixty-nine per cent of these patients would have fallen into this refraction bracket had calculation been made purely on clinical grounds. Comparison was made with 569 previous implantations without biometry. In this group life-long myopes above -3.0D had been excluded and the implants available were in 2.0 dioptre increments, choice of power depending on clinical judgement: 77 per cent of these patients fell into the same postoperative refraction bracket.

Humans↗

PubMed1994

[The role of routine ultrasonic screening in the antenatal diagnosis of fetal retardation].

The authors aim to evaluate the utility of ultrasound biometry in the diagnosis of IUGR. In a prospective study over 2.5 year period 142 pregnants at risk for IUGR were followed and their ultrasound results compared to those of 50 controls, investigated once after the 24 gestational week. The authors conclude that: BPD and FAC, evaluated only once, are unreliable in IUGR diagnosis; FAC is the most sensitive and specific index in onefold fetal biometry, particularly after the 34 gestational week; combing linear with non-linear parameters significantly increases.

Diagnostic Tests, Routine↗

PubMed2002

Clinical and theoretical results of intraocular lens power calculation for cataract surgery after photorefractive keratectomy for myopia.

OBJECTIVES: To describe the refractive results of cataract surgery after photorefractive keratectomy (PRK) for patients with myopia, and to find a more accurate method to predict intraocular lens (IOL) power in these cases. DESIGN: Nonrandomized, retrospective clinical study. PATIENTS AND METHODS: Nine patients (15 eyes) who underwent cataract surgery after prior PRK to correct myopia were identified. The medical records of both the laser and cataract surgery centers were reviewed. MAIN OUTCOME MEASURES: Eight different keratometric values (K values; measured or calculated) were entered into 3 different IOL calculation formulas: SRK/T, Holladay 1, and Hoffer Q. The actual biometry and IOL parameters were used to predict postoperative refraction, which was compared with the actual refractive outcome. Also, the relative underestimation of the refractive change in corneal dioptric power by keratometry after PRK was calculated. RESULTS: In 7 of 15 eyes, IOL exchange or piggybacking was performed because of hyperopia. Retrospectively, the most accurate K value for IOL calculation was found to be the pre-PRK K value corrected by the spectacle plane change in refraction. Use of the Hoffer Q formula would have avoided postoperative hyperopia in more cases than the other formulas. The mean underestimation of the change in corneal power after PRK varied from 42% to 74%, depending on the method of calculation. CONCLUSION: The predictability of IOL calculation for cataract surgery after PRK can be improved by using a corrected, refraction-derived K value instead of the measured, preoperative K value.

Adult↗

PubMed2003

Axial length-disc area ratio in esotropic amblyopia.

BACKGROUND: Hyperopia is a risk factor for esotropia and amblyopia. A previous study indicated that disc areas (DAs) are reduced in patients with amblyopia. OBJECTIVE: To determine if there is a difference in the relative size of the optic disc in hyperopic eyes without strabismus or amblyopia compared with esotropic and amblyopic eyes, the relationship of axial length (AXL) to DA in subjects with hyperopia was evaluated. METHODS: Eight hundred fifty records from my private practice, which included AXL measurements and optic disc photographs or digital images, were analyzed to locate 122 subjects with bilateral refractive errors greater than +2.00 diopters. Disc areas were measured using objective techniques. Axial lengths were determined by ultrasonographic biometry. A ratio, AXL/DA, was derived by dividing the AXL in millimeters by the DA in square millimeters. RESULTS: The mean (SD) AXL/DA for the group with hyperopia was 9.48 (2.70) mm and 12.30 (3.45) mm for the group with hyperopic strabismus (P =.01). The mean (SD) AXL/DA was 15.24 (4.61) mm in the amblyopic eyes and 13.61 (3.67) mm for the nonamblyopic fellow eye (P =.02). CONCLUSION: The optic discs of eyes with hyperopic strabismus with and without amblyopia were disproportionately and markedly reduced when compared with hyperopic eyes without amblyopia or esotropia.

Adult↗