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PubMed2003

Customizing fetal biometric charts.

OBJECTIVE: To study the effects of maternal and pregnancy characteristics on fetal biometric size using longitudinal ultrasound measurements and to construct customized models for fetal biometric size charts. METHODS: A cohort of 533 healthy pregnant women with normal singleton pregnancies were recruited for regular ultrasound examination for fetal biometry between 24 and 40 weeks' gestation. Multilevel modeling was used to construct models of fetal head size, femur length and abdominal circumference. Variables of maternal and pregnancy characteristics including booking weight and height, age, parity and fetal sex were included in the construction of the customized fetal biometric size charts. RESULTS: Increased fetal head size and abdominal circumference were significantly associated with extremes of maternal age. Maternal height had a statistically significant influence on biparietal diameter. Maternal booking weight had an influence on fetal abdominal circumference and femur length. Fetal sex was found to have a statistically significant influence on the final regression models of biparietal diameter, head circumference and femur length. Parity had an influence on fetal head circumference and abdominal circumference. CONCLUSIONS: Maternal and pregnancy characteristics have a significant influence on in-utero fetal biometry. We produced models to construct customized fetal biometric size charts. Further validation studies are necessary to evaluate the clinical usefulness of such customized fetal biometric size charts.

Adult↗

PubMed2005

The fetal cerebellar vermis: anatomy and biometric assessment using volume contrast imaging in the C-plane (VCI-C).

OBJECTIVES: To describe the normal appearance and study the biometry of the fetal cerebellar vermis by three-dimensional (3D) volume contrast imaging in the coronal (C-) plane (VCI-C). METHODS: A total of 203 normally developed fetuses were examined prospectively at 18-33 weeks' gestation. At the level of the view used to measure the transverse cerebellar diameter (TCD), a VCI-C plane was displayed to examine, using a transabdominal probe, the fetal mid-saggital vermis. The volumes acquired were stored for later review and measurement of the anteroposterior (AP) diameter, craniocaudal (CC) diameter and surface area of the cerebellar vermis. Each dataset was evaluated by two independent observers. Measurements as a function of gestational age (GA), biparietal diameter (BPD), head circumference (HC) and TCD were expressed by regression equations. Interobserver variability was evaluated. Nomograms were produced. In order to validate the use of VCI in fetal biometry, datasets from 57 patients were selected arbitrarily for comparison of their VCI-C measurements with those from mid-sagittal sections of a stored 3D multiplanar examination. Intraclass correlation was used to evaluate the agreement between these measurements. RESULTS: The mean maternal age was 32 years. We were able to measure mid-sagittal CC diameter, mid-sagittal AP diameter and cerebellar vermis surface area in all fetuses. Interobserver variability analysis showed no significant differences between the two observers (P > 0.05). Measurements of the cerebellar vermis (AP diameter, CC diameter and surface area) correlated linearly with GA, BPD, HC and TCD (r > or = 0.82, P < 0.0001). CC and AP diameters estimated from the mid-sagittal section of the multiplanar measurements were significantly correlated with VCI-C measurements (r = 0.96, P < 0.00001 and r = 0.95, P < 0.00001, respectively). CONCLUSIONS: VCI-C is a valuable tool, allowing intrauterine assessment of the normal appearance of the fetal cerebellar vermis. The nomograms developed in this study should enable accurate evaluation of the cerebellar vermis.

Adolescent↗

PubMed1994

Factors influencing the accuracy of the SRK formula in the intraocular less power calculation.

Several intraocular lens (IOL) power calculation formulas (either theoretical or empirical) are used to determine the emmetropic IOL power) The Sanders-Retzlaff-Kraff (SRK) linear regression formula is among the most widely recognized empirical ones. In the present study intraocular lens power calculation aiming at emmetropia was performed, using SRK formula, in 145 cataractous eyes undergoing lens implantation. The final refraction was evaluated at 8 to 12 months after surgery. The purpose of this study was the identification and quantitative evaluation of the factors which influence significantly the accuracy of SRK in the intraocular lens power calculation. The following factors were studied: (1) the error in preoperative biometry with regard to the difference between post and preoperative axial length measurements, (2) the position of the implantation of the intraocular lens (anterior versus posterior chamber), (3) the intraocular lens style, (4) the intraocular lens power level, (5) the preoperative corneal astigmatism, (6) the surgically induced corneal astigmatism, and (7) the postoperative astigmatism. Multiple regression and stepwise regression analysis showed a strong correlation (R2 = 0.65; p < 0.001) between postoperative refractive error (Rf) and error in preoperative biometry (delta AL), surgically induced corneal astigmatism (SIA) and postoperative astigmatism (Ap) only. This correlation is expressed by the following equation: Rf = 0.07 -2.55 delta AL -0.42 SIA + 0.34 Ap. This equation indicates the quantitative effect of each factor on the accuracy of the SRK formula, by defining the pattern of the fluctuations of the amount or state (myopic or hyperopic) of refractive error induced by changes of variables delta AL, SIA and Ap.

Aged↗

PubMed2005

Evaluation of biometric methods for measuring the anterior chamber depth in the non-contact mode.

PURPOSE: High-resolution biometry of the anterior ocular segment is now becoming more and more important against a background of refractive surgery and the evaluation of potentially accommodative lens replacement materials. The aim of this study was a systematic investigation of the currently available non-contact methods for measuring the anterior chamber depth (ACD). METHODS: The ACDs of 50 phakic eyes of 27 patients aged between 19 and 59 years were measured with the IOL-Master (Zeiss), the AC-Master (Zeiss), the Pentacam (Oculus) and slit-lamp pachymetry by Jaeger (Haag-Streit). RESULTS: The median anterior chamber depth in the investigated eyes was 3.63 mm for the IOL-Master (minimum 2.88 mm, maximum 4.22 mm), 3.802 mm for the AC-Master (2.816 mm-4.373 mm), 3.915 mm for the Pentacam (minimum 2.994 mm, maximum 4.614 mm) and 3.75 mm for Jaeger (2.887 mm-4.29 mm). With a probability of error of alpha=0.05 there were no significant differences concerning the ACD between the methods of Jaeger and AC-Master, Jaeger and IOL-Master, or Pentacam and AC-Master (Wilcoxon and Wilcox). The intra-individual variability was +/-5.4 microm for AC-Master, +/-12.7 microm for Pentacam, +/-24.5 microm for IOL-Master and +/-41.2 microm for Jaeger. The maximum method-dependent difference in ACD determination was 285 microm. CONCLUSIONS: All the methods allow non-contact biometry, but the results might differ due to measuring principles inherent to the system, experience of the examiner and compliance of the patient. Partial coherence interferometry with the AC-Master offers the advantage of measurement exactly along the optical axis with the highest reproducibility and patient compliance.

Adult↗

PubMed2004

Ocular refraction: heritability and genome-wide search for eye morphometry traits in an isolated Sardinian population.

No genes influencing oculometric phenotypes have yet been identified, despite it being well known that eye morphometry is involved in refraction and that genetics may play an important role. We have therefore performed a heritability analysis and genome-wide search (GWS) of biometric ocular traits in an isolated Sardinian population, assessing the genetic contribution and identifying the associated genetic loci. A complete eye examination including refraction and ocular biometry measurements such as axial length (AL), anterior chamber depth (ACD) and corneal curvature (CC), was performed on 789 subjects. Heritability analysis was carried out by means of parent-offspring regression and variance component models. Univariate and bivariate linkage analysis was performed by using 654 microsatellite markers spanning the genome. CC showed a mean heritability of 57%. AL and ACD were found to have significantly different variances (P<0.01) in males and females, so that heritability was calculated separately for each sex. AL had an estimated heritability in females of 31% and in males of 60%, whereas ACD had an estimated heritability of 47% in females and of 44% in males. In the GWS, the most suggestive evidence of linkage was identified on chromosome 2 for AL (LOD 2.64), on chromosome 1 for ACD (LOD 2.32) and on chromosomes 7, 2 and 3 for CC (LOD 2.50, 2.44 and 2.34, respectively). High heritability of eye morphometry traits was thus revealed. The identified loci are the first linkage signals available in ocular biometry. Notably, the observed significant differences in parental transmission deserve further study.

Adolescent↗

PubMed1996

Characterisation of the possible effect on birthweight following frequent prenatal ultrasound examinations.

The objective of this study was to evaluate and characterise by study of newborn biometry a possible effect on birthweight which we observed previously in a randomised controlled trial of multiple prenatal ultrasound examinations. A total of 2743 women with single pregnancies had been allocated at random to either a protocol of ultrasound imaging and continuous wave Doppler studies at 18, 24, 28, 34 and 38 weeks gestation (intensive group), or to a protocol of a single imaging examination at 18 weeks and further imaging scans only as clinically indicated (regular group). When compared with those in the regular group, and adjusted for other confounding variables, normally formed babies of term gestational age in the intensive group tended to be shorter when measured at birth (P = 0.123) and on day 2-3 of age (P = 0.068). There were statistically insignificant reductions in the circumferences of the chest, abdomen and mid-arm; and in the skinfold thicknesses of the triceps, parascapular and subscapular regions. Principal component analysis showed a trend for a reduction for the skeletal component (P = 0.085) but not for the soft tissue component (P = 0.332). Comparison of the neonatal biometry in the two groups is not conclusive, but the differential effects on the various growth parameters suggest that if multiple scans do indeed restrict fetal growth, the mechanism is more likely to be an effect on bone growth rather than a reduction in nutrient supply from the placenta.

Biometry↗

PubMed2004

Differences in fat and lean mass proportions in normal and growth-restricted fetuses.

OBJECTIVE: The purpose of this study was to assess fetal subcutaneous fat and lean mass areas as predictors of fetal growth restriction. STUDY DESIGN: Seventeen severe fetal growth-restricted (abdominal circumference, < 2 SD) fetuses and 20 control fetuses underwent ultrasound measurements of subcutaneous fat, lean mass, and standard biometry. Thigh subcutaneous fat and lean mass were measured on enlarged ultrasound axial images (subcutaneous fat area = total cross sectional area - lean mass area [bone + muscle areas]). Subcutaneous fat and lean mass areas were expressed as a percentage of the total cross-sectional area and were normalized to femur length and head circumference. Measurements were modeled as a function of fetal growth-restriction status and week of gestation with multiple linear regression. RESULTS: Fetal growth-restriction fetuses showed reductions in fat and lean mass (in standard biometry) and showed a disproportionate reduction in fat mass compared with lean mass. These were all associated significantly with fetal growth restriction. CONCLUSION: Fetal growth-restricted fetuses have reduced subcutaneous fat and lean mass compared with control fetuses; a further reduction occurs in subcutaneous fat concentration compared with the reduction in lean mass when fat is normalized for body size, with either head circumference or femur length. Fat-to-bone proportions may be useful in distinguishing the small for gestational age fetus who is truly fetal growth restriction from the constitutionally small fetus.

Biometry↗

PubMed2004

Effect of accommodation and pupil size on the movement of a posterior chamber lens in the phakic eye.

PURPOSE: Although a posterior chamber phakic intraocular lens provides effective refractive correction of high myopia and hyperopia, mechanical contact between the implantable contact lens (ICL) and the crystalline lens and inadequate aqueous circulation in the prelenticular space could cause subcapsular opacification. To assess whether and to what extent such mechanical contact occurs, changes in the distance between the STAAR Collamer ICL and the crystalline lens under various conditions were investigated. DESIGN: Open pilot study. PARTICIPANTS: Thirteen eyes of 11 myopic and 2 hyperopic patients with a mean age of 38 years (range, 19-53 years) were examined at least 6 months after ICL implantation. METHODS: A noninvasive, high-resolution biometry technique, partial coherence interferometry, was used to measure distance changes between the ICL and the crystalline lens during subjective accommodation, after instillation of pilocarpine, and under changing light conditions. MAIN OUTCOME MEASURES: Mean distance changes from the posterior corneal surface to the ICL, from the posterior corneal surface to the anterior surface of the crystalline lens, and the distance between the ICL and the crystalline lens. RESULTS: In the nonaccommodated state, the mean distance between the ICL and the crystalline lens was 457 microm (range, 123-924 microm). During subjective accommodation, a significant (P<0.01) decrease and, after topical application of pilocarpine, a nonsignificant (P=0.35) decrease of anterior chamber depth was accompanied by a nonsignificant (P = 0.71) reduction of the ICL-crystalline lens distance. Under photopic conditions, a significant mean reduction (P<0.01) of the ICL-crystalline lens distance of -28 microm (range, -16 to -188 microm) was observed. CONCLUSIONS: Partial coherence interferometry biometry enabled noninvasive high-precision investigation of ICL dynamics. No significant changes between the ICL and the crystalline lens were detected during subjective accommodation and after application of pilocarpine. However, under photopic conditions, with constriction of the pupil, the distance between the ICL and the crystalline lens was significantly reduced. This mechanism might cause inadequate aqueous circulation in the prelenticular space and might be one of the causes of subcapsular opacification in some of the eyes after ICL implantation.

Accommodation, Ocular↗

PubMed2005

Effect of myopia on visual acuity measured with laser interference fringes.

The aim was to determine how visual acuity is affected by myopia when optical factors of the eye are controlled. Grating acuity was measured with interference fringes to avoid the effects of aberrations, and ocular biometry was used to compensate for differences in retinal image size among subjects. Distance spectacle refractions ranged from +2.25 to -14.75 D. The retinal magnification factor (RMF) in mm/deg was computed for each eye from the distance refraction, central corneal power and ultrasound biometry. A forced-choice orientation discrimination method was used to measure acuity for high-contrast 543 nm laser interference fringes in three retinal locations: the fovea, and at 4 deg and 10 deg eccentricity in the temporal retina. Acuity, expressed in c/deg and adjusted for spectacle magnification, was not significantly correlated with refraction at any of the three retinal locations. When acuity was converted to retinal spatial frequency units (c/mm) via the RMF, acuity decreased with increasing myopia at all three retinal locations (significantly at the fovea and at 10 deg eccentricity). Retinal acuity values in highly myopic subjects (>6 D) are consistent with retinal sampling distances that are larger than published values of human cone or ganglion cell spacing. The results imply that a highly myopic eye has retinal neurons that are more widely spaced than normal, but the increased axial length enlarges the retinal image enough to compensate for the retinal stretching. The data are consistent with a retinal stretching model that primarily affects the posterior pole.

Adult↗

PubMed1996

Ultrasonographically adjusted midtrimester risk of trisomy 21 and significant chromosomal defects in advanced maternal age.

OBJECTIVE: Our purpose was to determine whether normal midtrimester ultrasonography results reduces the risk of fetal Down syndrome and any clinically significant chromosomal defects in pregnancies with advanced maternal age and to develop risk tables on the basis of age and ultrasonographic results. STUDY DESIGN: Biometry data were obtained in 4079 women between 15 and 24 weeks undergoing amniocentesis for maternal age. Expected values of humerus, femur, both combined, and abdominal circumference based on biparietal diameter were generated from a normal group. Observed/expected values of each parameter and nuchal thickness > or = 6 mm was used to screen for Down syndrome and any clinically significant chromosome defects. Receiver-operator characteristic curves were used to determine threshold screening values for each parameter. By use of stepwise logistic regression the optimal measurements for detection of chromosome anomalies were established. An abnormal ultrasonography result was defined as either abnormal biometry choroid plexus cysts or a structural defect. RESULTS: The finding of shortened humerus (observed/expected < 0.90), abnormal nuchal thickness, or an anatomic defect had the highest sensitivity for Down syndrome detection, 70.6%, p < 0.0001, whereas a short humerus, small abdominal circumference, (observed/expected < 0.92), or an anatomic defect had a sensitivity of 46.7%, p < 0.0001, for any significant chromosome defect. With a normal ultrasonography the risk of Down syndrome in a 39-year-old woman falls from 1:100 to < 1:292. CONCLUSION: A normal ultrasonography substantially reduces the risk of Down syndrome and any chromosome abnormality. This information is useful in counseling women who decline amniocentesis on the basis of maternal age.

Biometry↗

PubMed1996

Receiver-operator characteristic curves for the ultrasonographic prediction of small-for-gestational-age fetuses in low-risk pregnancies.

OBJECTIVE: Our purpose was to assess the accuracy of third-trimester ultrasonographic biometry in the diagnosis of small-for-gestational-age fetuses in a low-risk obstetric population. STUDY DESIGN: A total of 1000 low-risk pregnancies were prospectively examined at 31 weeks' gestation. The diagnostic accuracy of the fetal abdominal circumference and estimated fetal weight according to 24 formulas in the literature were evaluated by the use of receiver-operator characteristic curves. RESULTS: The incidence of a birth weight <10th percentile was 8.2%. The diagnostic accuracies of abdominal circumference and estimated fetal weight were remarkably similar. None of the 24 formulas performed significantly better than the measurement of the abdominal circumference. At a specificity of 90%, 46% of infants with a birth weight <10th percentile and five of six cases with adverse perinatal outcomes were predicted. CONCLUSION: In a low-risk obstetric population third-trimester ultrasonographic biometry has limited value in predicting small-for-gestational-age fetuses, and estimation of fetal weight does not carry an advantage over measurement of the abdominal circumference. The optimal cutoff value remains uncertain. However, by accepting a 10% false-positive rate, half of small-for-gestational-age fetuses and most perinatal complications could be recognized.

Abdomen↗

PubMed2002

A comparison of laser photocoagulation with cryotherapy for threshold retinopathy of prematurity at 10 years: part 2. Refractive outcome.

OBJECTIVE: To compare the refractive outcome of eyes treated with cryotherapy for threshold retinopathy of prematurity (ROP) with eyes treated with laser photocoagulation. DESIGN: Extended follow-up of a randomized controlled clinical trial. PARTICIPANTS: One hundred eighteen eyes from 66 patients were randomly assigned to receive either cryotherapy or laser photocoagulation for threshold ROP. Twenty-five patients (44 eyes treated) were available for follow-up examination 10 years later. INTERVENTION: Cycloplegic autorefraction or retinoscopy was performed. Immersion ultrasound biometry (A-scan) was also performed, and an autokeratometer was used for keratometry. If an A-scan could not be tolerated or the patient was not cooperative, a B-scan through-the-lid biometry was performed. Corneal thickness was measured using optical coherence tomography. MAIN AND SECONDARY OUTCOME MEASURES: Refractive error. In addition, anterior chamber depth, lens thickness, and axial length were measured. Central corneal thickness measurements and keratometric readings were also obtained. RESULT: Eyes treated with cryotherapy were significantly more myopic than those treated with laser photocoagulation. When comparing patients with bilateral treatment, the mean spherical equivalent (SE) of eyes treated with laser was -4.48 diopters (D) compared with a mean SE of -7.65 D for eyes treated with cryotherapy (n = 15 pairs of eyes, P = 0.019). Cryotherapy-treated eyes had a mean axial length of 21.7 mm versus 22.9 mm for laser-treated eyes (P = 0.024, n = 12 pairs of eyes). The anterior chamber depth and lens thickness averaged 2.86 mm and 4.33 mm, respectively, in the cryotherapy-treated eyes compared with 3.42 mm and 3.95 mm in the laser-treated eyes (P < 0.001, n = 12 pairs for both measurements). There were no statistical differences in anterior corneal curvature and central corneal thickness between the two treatment modalities. Crystalline lens power bore the strongest correlation to refractive outcomes in both laser-treated (r = 0.885, P < 0.001) and cryotherapy-treated eyes (r = 0.591, P = 0.026). Although keratometric readings were higher than normal values in these eyes, there was no correlation to the degree of myopia. CONCLUSIONS: Laser-treated eyes were significantly less myopic than cyrotherapy-treated eyes. Lens power seemed to be the predominant factor contributing to the excess myopia.

Anterior Chamber↗

PubMed2002

Component dependent risk factors for ocular parameters in Singapore Chinese children.

OBJECTIVE: To examine the risk factors for variations in ocular biometry parameters in Singapore Chinese children, a population with a known high prevalence rate of myopia at an early age. DESIGN: Cross-sectional study. PARTICIPANTS: Children aged 7 to 9 years (n = 1453) from three schools in Singapore. METHODS: The children underwent A scan biometry and cycloplegic autorefraction measurements. Questions were asked regarding number of books read per week, night lighting, and parental myopia. MAIN OUTCOME MEASURES: Axial length, vitreous chamber depth, lens thickness, anterior chamber depth, refraction, and corneal curvature radius measurements were made. RESULTS: After controlling for several factors, the axial lengths were found to be longer and vitreous chambers deeper in children who were older, male, read more than two books per week, or taller, and those who had at least one parent who was myopic. In these models, children who read more than two books per week had axial lengths that were 0.17 mm longer and vitreous chambers that were 0.15 mm deeper compared with children who read two or fewer books per week. Anterior chambers were deeper in males and taller children, whereas corneal curvature was steeper in female, older, and shorter children. CONCLUSIONS: Increases of axial length and vitreous cavity depth were associated with older age, being male, reading more than two books per week, increased height, and parental history of myopia. Of these risk factors, however, neither reading nor parental myopia history were associated with values for anterior chamber depth, corneal curvature, or lens thickness. These findings confirm that conventional risk factors for myopia associated with the vitreous cavity, but suggest that anterior segment parameters such as corneal curvature and lens thickness may be subject to unrelated postnatal growth control mechanisms.

Age Distribution↗

PubMed2000

[Hybridization and introgression between "full-fledged species". The case of Parnassius apollo and P. phoebus].

Two butterfly species living in the Alps, Parnassius apollo and P. phoebus, frequently hybridize in certain localities of this region. The features of this phenomenon have been previously studied by biometry and starch gel electrophoresis, but some points remained obscure. We present them in a study combining results from cellulose acetate electrophoresis and wing pattern biometry with a determination of the mitochondrial haplotype by a PCR-RFLP analysis in a sample of butterflies from the southern French Alps. It was already known that the male hybrids are fecund and thus that interspecific gene exchange could take place via backcrosses with the parent species. In the present case, combining the identification of mtDNA with the analysis of nuclear genotypes allows us to demonstrate that hybridization can involve both sexes of both species. Moreover, it suggests that at least some female hybrids are not sterile. The impact of Haldane's rule is therefore not very strong in the present case. However, although the prerequisites for introgression between the concerned species are fulfilled, at the level of both nuclear and mitochondrial genomes, no indication of such a phenomenon could be gathered in the studied sample.

Animals↗

PubMed2002

Intraocular lens power calculation after macular hole surgery.

A patient had cataract surgery in both eyes after bilateral macular hole repair. In the left eye, the intraocular lens power was calculated using the axial length obtained by biometry. In the right eye, 0.5 mm, the estimated depth of the foveolar crater after stage 3 macular hole repair, was subtracted from the A-scan measurement to obtain the functional axial length. Postoperatively, refraction was +0.25 diopter (D) in the right eye and +1.63 D in the left eye. Biometry after macular hole surgery should be corrected by subtracting the depth of the foveolar crater from the measured axial length.

Aged↗

PubMed1999

Perspectives of clinical epidemiology in Germany.

The aim of this article is to discuss the perspective of clinical epidemiology in Germany. The following statements are discussed: (1) There is some confusion about the definition of clinical epidemiology. (2) There is a latent and growing need for clinical epidemiology in Germany. (3) Clinical epidemiology is an interdisciplinary field and not simply clinical medicine, epidemiology, biometry, or medical informatics. (4) We must continue with the education of clinicians and nonclinical methodologists in clinical epidemiology to develop the field of clinical epidemiology in Germany, Biometry, medical informatics, and epidemiology will play an essential role for this purpose. (5) The German scientific community urgently needs clinicians and scientists with experience in methodological research to specialize in the methods of clinical epidemiology. (6) The starting point for the development of clinical epidemiology in Germany, clear deficits in the past notwithstanding, is promising. However, we will only be able to develop the field if the egoism of the different disciplines can be tamed.

Biometry↗

PubMed2000

Silicone intraocular lens compression and double lens implants in diseased eyes.

PURPOSE: To assess the outcomes of double lens implants in hyperoptic eyes with associated pathology. METHOD: Double lens implants were used in 4 eyes of 4 patients each with a different ophthalmic or neuro-ophthalmic disease. Biometry was performed in the standard contact fashion and lens power formulae used included SRK/T, Holladay and Hoffer Q. RESULTS: Average spherical equivalent refraction improved from +6.875 D to +0.38 D. Absolute average prediction error was greatest for SRK/T (2.65 D) and least for Holladay (1.73 D). Refractive suprises were influenced by the underlying disease process. One patient showed central lens compression. CONCLUSION: Underlying disease can produce biometry errors. Structural ophthalmic or neurological disease is not a contraindication to the use of double lens implants. Double lens implants are useful to correct refractive error in the presence of underlying disease.

Adult↗

PubMed2006

Reliability of the IOLMaster in axial length evaluation in silicone oil-filled eyes.

PURPOSE: To assess the reliability of IOLMaster in axial length (AL) measurement in phakic silicone oil-filled vs pseudophakic saline-filled eyes. METHODS: Ten eyes of 10 patients, vitrectomized with silicone oil tamponade and scleral buckled with significant lens opacity were enrolled. Optical biometry with IOLMaster (Carl Zeiss Meditec AG, Germany) was performed 1 day before and 1 week after silicone oil removal and phacoemulsification with artificial intraocular lens (IOL) implantation in order to assess changes in AL measurements. RESULTS: Mean AL was 26.16+/-1.23 mm (range 24.64-28.8 mm) and 26.27+/-1.46 mm (range 25.26-29.6 mm), respectively, the day before and 1 week after silicone oil removal and cataract surgery, and the difference was not statistically significant (P=0.2). CONCLUSIONS: Presence vs absence of silicone oil tamponade as well as phakic vs pseudophakic status in buckled and vitrectomized eyes did not influence the AL measurement by means of no-contact optical biometry, suggesting that such eyes might be candidate for silicone oil removal and cataract surgery at one time.

Aged↗