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At least 937 records · Page 52Linked to original sources

PubMed2002

[Pitfalls of IOL power prediction after photorefractive keratectomy for high myopia -- case report, practical recommendations and literature review].

BACKGROUND AND PURPOSE: Published experience with eyes after keratorefractive correction of myopia indicates that insertion of the average keratometric readings into standard IOL power predictive formulas will frequently result in substantial undercorrection and postoperative hyperopic refraction or anisometropia after cataract surgery depending on the amount of myopia corrected previously. The purpose of this paper is to discuss the accentuated differences of various approaches to minimize IOL power miscalculations by describing a case report of a patient with excessive myopia as well as a review of the literature. PATIENT AND METHODS: A 50-year old lady presented for cataract surgery on her left eye after having PRK seven years ago elsewhere (refraction - 25.5 - 3.0/20 degrees, central keratometric power 43.0 diopters [D]). Central power before cataract extraction was measured to be 35.5 D (Zeiss Keratometer) and 36.5 D (TMS-1 topography analysis) and refraction was - 3.0 D (before onset of index myopia). Orbscan slit scanning topography analysis displayed an anterior surface power of 36.8 D and a posterior surface power of - 9.3 D. Total axial length was 31.93 mm (optical biometry using Zeiss IOL-Master). The contralateral eye after PRK suffering from a comparable excessive myopia had required an exchange of the IOL implant because of intolerable anisohyperopia of + 6.0 D after primary cataract extraction elsewhere. RESULTS: Corrected corneal power values for the left eye were calculated as follows: (1) spherical equivalent (SEQ) change at spectacle plane 19.0 D, (2) SEQ change at corneal plane 26.2 D, (3) separate consideration of anterior and posterior curvature 27.5 D, (4) consideration of the IOL power misprediction on the fellow eye 29.5 D, (5) subtraction of 24 % of the SEQ change at the spectacle plane from the actually measured keratometry value 29.7 D, (6) clinical estimate from regression analysis performed earlier 30.5 D, (7) change of anterior surface power 34.5 D. Deciding for a presumably "real" corneal power of 28.0 D the Haigis formula was used to aim for - 2.0 D since the patient preferred to read uncorrected. Thus, a 21.0 D IOL was implanted uneventfully in the capsular bag. The stable refraction postoperatively was - 3.5 - 1.0/20 degrees and visual acuity increased to 20/30. Therefore, the "real" power of that cornea must have been around 30 D. CONCLUSIONS: After corneal refractive surgery, various techniques to determine the current corneal power should be compared and the value around which results tend to cluster should be relied on to avoid hyperopia after cataract surgery with lens implantation. In those cases where keratometry and refraction before PRK/LASIK are available, the gold standard is still to subtract the change of the SEQ at the corneal plane from the preoperative central keratometric power, although in the present case report the subtraction of 24 % of the SEQ change at the spectacle plane from the measured corneal power value seemed to produce the best result. Pure subtraction of the SEQ change at the spectacle plane from the corneal power value before refractive surgery has to be avoided in eyes with excessive myopia. The most reliable corrected power value should be inserted in more than one modern third-generation formula (such as Haigis, Hoffer Q, Holladay 2, SRK/T) and the highest power IOL should be implanted. In all instances, the cataract surgeon has to make sure that the corrected K-reading is not wrongly re-converted within the IOL power calculation formula used.

Corneal Topography↗

PubMed2004

[Angle closure glaucoma in association with relative anterior microphthalmus (RAM) after premature birth-retinopathy (ROP)].

BACKGROUND: The infantile angle-closure glaucoma is a common and well characterized complication of retinopathy of prematurity (ROP). Progressive shallowing of the anterior chamber by retrolental fibrous masses is mostly responsible for the pressure elevation during the first years of life. Apart of this pathogenesis, ROP-associated glaucoma is totally different in cases that do not manifest until adulthood. Only few cases are described in the literature. CASE REPORT: A 36-year-old female patient presented with symptoms of acute intraocular pressure (IOP) elevation and fundus results of a cicatricial ROP stadium II. Control of IOP was not achieved by systemic and topical drug treatment. The biometry showed a relative anterior microphthalmus (RAM) in myopia. After peripheral iridectomy, the IOP normalized and remained stable over a long-time period. CONCLUSION: Myopia induction after ROP and ROP treatment often lead to special anatomical conditions corresponding to the classical relative anterior microphthalmus. Shallowing of the anterior chamber and development of angle-closure glaucoma increase with age. Thus, a manifestation not before the third decade of life was a typical finding in the literature review. A detailed recording of history and consideration of the biometric data are of importance for diagnosis. Peripheral iridectomy was found to be the therapy with the highest success rate. The increase of a pupillary block mechanism can prevent further visual loss to the often pre-damaged eyes. Consideration of this entity is crucial in unilateral IOP elevation, because an increasing prevalence of these patients can be expected due to the increase of premature babies since 1970.

Adult↗

PubMed2004

[The competence network "acute and chronic leukemias"].

Leukemias are a challenge and a cost factor to society because of their frequency in all age groups. They also serve as a model for a variety of diseases and possess exemplary relevance for basic research and patient care. Leukemia research and therapy have achieved high standards and even a leading position in Germany with regard to clinical trials, standardization of diagnostics and molecular studies of prognostic factors, signal transduction and gene expression. Progress is hampered, however, by fragmentation of leukemia trial groups, diagnostic approaches and treatment research activities. A network was therefore created to integrate the leading leukemia trial groups on chronic myeloid leukemia (CML), acute myeloid leukemia (AML), acute lymphatic leukemia (ALL), myelodysplastic syndromes (MDS) and chronic myeloproliferative diseases (CMPD) and their interdisciplinary partners (diagnostics, treatment research, biometry) in cooperation with basic research and pharmaceutical industry to foster advancements in leukemia-related research and health care through clinical trials, promotion of translational research, introduction of standards for diagnostics and therapy, and development of evidence-based guidelines. Achievements include establishment of central information, communication and management structures, creation of an AML intergroup comprising five study groups, formation of a myelodysplastic syndromes study group and establishment of platforms for diagnostics, genomics and proteomics, and medical informatics. Exchange of scientific progress is mediated by intra- and internet, bi-annual newsletters, regular project group meetings and annual network symposia. Already now, the network structures leukemia therapy and research in Germany and supports the spread of scientific excellence in the field of leukemias.

Acute Disease↗

PubMed1995

[Orbital diameter, inner and outer orbital distance. A growth model of fetal orbital measurements].

AIM: Aim of this study was to establish a growth model for the intrauterine growth of the following fetal parameters: orbital diameter, interorbital and biocular diameters. METHOD: Data were measured in a prospective cross-sectional study with real-time ultrasound. The study group consisted of 1090 healthy fetuses between 12 and 41 weeks gestation. For curve standardisation a growth model for all parameters was used. RESULTS: Using this growth model growth profiles (5., 50., and 95. percentiles) were established. All orbital parameters showed a nonlinear growth. CONCLUSION: Since ocular and orbital malformations (anophthalmia, microphthalmia, hypo- and hypertelorism) are often principal signs of generalised syndromes, orbital biometry is helpful for a detailed prenatal investigation of the fetal face. This is demonstrated in 2 cases with an orbital malformation (orbital hypoplasia, hypotelorism).

Cephalometry↗

PubMed1994

[Ultrasound assessment of the postmenopausal endometrium. Is measuring thickness adequate?].

Sonographic assessment of the endometrium in postmenopausal women is generally based on total thickness as only criterion. The cut-off values recommended in literature, however, vary considerably. The purpose of this study was to examine the significance of sono-morphology besides biometry of the endometrium. If vaginosonography showed an endometrial thickness of 3 mm or less, all histological findings were inconspicuous; beginning at a thickness of 10 mm only hyperplasias, polyps and carcinomas were found. In the range between, including more than one-third of our patients, the structure can point out the type of histology: Homogeneity, low echogeneity and a median echo are not important findings, but inhomogeneity and high echogeneity point to pathological changes of the endometrium. Using combined, metric-structural criteria in vaginosonography of the endometrium, not only the predictivity, but above all the selectivity is improved.

Adenoma↗

PubMed1993

[Apple-Macintosh compatible software for documentation, management and evaluation of ultrasound findings in obstetrics].

The advantage of using a computer to automate routine calculations and print out charts of the obstetrical ultrasound examination is obvious. This report describes a software designed to simplify the documentation and analysis of ultrasound data in obstetrics. The system is easy to use, even for persons with little computer knowledge. The programme was written in FoxBase+/Mac (Fox Software, Inc., USA). FoxBase+/Mac takes full advantage of the easy-to-learn, easy-to-use Macintosh interface and is also very fast. Another advantage of this software is that it can be used in teaching. Non-experienced examinators can double-check the correctness of their scanning planes by observing the ultrasound pictures with the markers indicating the right measurement sites and the lists of standard values of biometrical parameters for the corresponding gestational age on the screen. In routine obstetrical ultrasound examinations it takes less than 5 min to enter the foetal biometry data and print out reports. These reports are informative and easy to interpret.

Female↗

PubMed1985

[Quality control in obstetrical ultrasound diagnosis].

Experience with sonographic pregnancy care have demonstrated the necessity of quality control. Before a person is licensed to take account for sonography he should prove, that he has performed a certain number of examinations and that he is holding a file of documents on these examinations. This certificate should ensure that the fundamental knowledge of foetal sonographic anatomy and biometry as well as of possible signs of foetal malformations have been correctly acquired. As a provisional arrangement until sonography is fully integrated into gynaecological education, an examination by a board would appear to be desirable.

Cephalometry↗

PubMed1982

[Use of ultrasound in ophthalmology].

In ophthalmology, ultrasound is applied in diagnostics as well as in surgery and therapy. This paper gives a short survey on both applications. Ultrasonic phacoemulsification is of considerable practical importance for modern cataract micro-surgery with intraocular lens implantation. Applications of that kind require consideration of ultrasonic bioeffects and equipment safety. Diagnostic use of ultrasound includes biometry (echometry), tissue examination and characterization, and vascular investigations in eye and orbit. The application of diagnostic ultrasound on in-patients, its individual indications, and the appropriate methods (A, B, automatic biometric devices for axial length measuring, M, Doppler) are described. Examples of commercially available instruments for the different applications are given. In comparison with other disciplines ophthalmic A-mode and B-mode echography is characterized by: refined depth resolution and lateral resolution; the important part of quantitative methods for clinical evaluation of echograms; and the advanced level of quality assurance for equipment performance. Refined tissue evaluation requires optimized and reproducible equipment parameters. To ensure these conditions the clinical echographer must be educated and willing to test performance and quality of his equipment. Finally, a perspective of actual research in diagnostic ultrasound of the eye is given.

Equipment Design↗

PubMed1993

[Doppler ultrasound in high grade multiple pregnancies].

From 1987 until 1992, 16 triplets and 2 quadruplets were studied by pulsed Doppler ultrasound between 17 and 36 weeks of gestation. A resistance index (RI) of the foetal aorta and umbilical artery above the 95th percentile was considered pathological. Elevated RI-values of the umbilical artery as compared to the A. cerebri media were indicative of circulatory centralisation. Intrauterine growth retardation (IUGR) was found in 9 (16%) foetuses, discordant growth occurred in 7 (39%) pregnancies. 41 (73%) of 56 foetuses survived in good health. Four of 7 foetuses with pathological Doppler findings died. The three survivors were markedly retarded. Four of 6 cases of intrauterine endangered foetuses were detected by Doppler sonography. The diagnosis of IUGR or discordant growth was based more frequently on pathological Doppler findings than on biometry and improved upon by combinations of both methods. Doppler sonography proved to be an important complementary method in the monitoring of high-grade multiple pregnancies.

Adolescent↗

PubMed1994

[Effect of ultrasound examination on fetal version of breech presentation].

External version was attempted in 70 pregnancies with foetuses in breech presentation near term. Version was successful in 50 patients (71%), 40 of whom delivered vaginally (80%). Of the 20 patients in whom version was not successful, only 7 patients (35%) delivered vaginally. 2 patients required immediate Caesarean section after attempted version because of ominous foetal heart rate patterns. We analysed the sonographic parameters associated with successful version. The location of the placenta, amount of amniotic fluid, foetal biometry (estimated foetal weight, cephalic circumference, abdominal diameter, femur length) and extension or flexion of the foetal head were analysed. Only extended legs correlated with the success of the procedure. The results suggest, that ultrasonography is an important prerequisite for successful version of a foetus in breech presentation near term.

Adult↗

PubMed1993

[Discordant growth in twin pregnancy--value of Doppler ultrasound].

A 4 MHz continuous-wave Doppler device was used to study uterine and umbilical arterial wave forms in 91 pairs of twins between 18th and 40th week of gestation. Biometry and cord localisation were effected by real-time ultrasound. The results of 182 Doppler flow examinations showed that umbilical flow velocimetry may prove relevant for early identification of twin pregnancies with discordant growth. Depending on the interval between examination and delivery, sensitivity and specificity values between 44% and 66%, and 66% and 73%, respectively, were obtained. A high resistance index in umbilical arteries was indicative of intrauterine growth retardation, at a specificity of 69% and a sensitivity of 44%. For uteroplacental as well as foetoplacental flow velocity waveform assessment, singleton reference values may be used, whereas, by reason of its low sensitivity, Doppler flow velocimetry does not lend itself as a primary diagnostic tool for intrauterine growth retardation. It can signal pathologic blood flow profiles, which are often associated with added risks, such as pregnancy-induced hypertension, foetal acidosis and stillbirth and can contribute to early detection of twin pregnancies that require close clinical and cardiotocographic surveillance.

Blood Flow Velocity↗

PubMed1993

[Does 3D sonography present new perspectives for gynecology and obstetrics?].

3D-sonography opens a new chapter of ultrasound-imaging. The aim of our study was, to summarise our preliminary experiences in the clinical application of this method. One-hundred and fifty patients were investigated with the use of transabdominal transducers. The scanning is performed after targeting the three-dimensional region by the volume box. The three planes are displayed simultaneously on the screen. Analysis can be performed on any possible plane within the stored volume (tomography). Surface imaging and transparent imaging can be calculated and displayed by a work-station. Three-dimensional ultrasound makes complete imaging and documentation of sonographically investigated structures feasible. The possibility of arbitrarily often repeatable systematic analyses without risk for the patient seems to be the more important advantage than statistical simultaneous imaging. Plastic imaging of structures, especially of foetuses, in the surface and transparent modes has been made possible for the first time. Biometry can also be measured in three dimensions (volumetry). Volume documentation provides the possibility of arbitrarily repeatable "real-time" scanning. By this means, any plane can be reanalyzed, remeasured and reassessed. This kind of documentation provides advantages in clinical, scientific, didactic and legal aspects. The first experiences with this new method seem to be promising. Further studies have to be conducted to evaluate the diagnostic significance of 3D-sonography in our field of specialisation.

Congenital Abnormalities↗

PubMed1995

From biochemical to biophysical placental function tests in fetal surveillance.

Radioimmunoassays of human placental lactogen and estriol levels in the maternal plasma, ultrasound biometry of the abdominal diameter (AD), pulsed Doppler measurements of uteroplacental arteries, the common carotid artery (CCA), and the umbilical artery (UA) and fetal heart rate monitoring were simultaneously performed in 219 risk pregnancies from 26 weeks' onward at regular intervals. The prognostic value of all tests to predict small for gestational age infants (SGA) and fetal distress was evaluated simultaneously. Receiver operator characteristic allowed the simultaneous comparison of all methods: The AD was most predictive for early detection of SGA, even more than uteroplacental blood flow. Fetal blood flow redistribution expressed as a ratio of the resistance index of CCA/UA was the most significant test for detection of fetal distress later in pregnancy, even more than antenatal cardiotocography. Considering cutoff levels used in clinical routine, the sensitivity and specificity of the fetal AD in detecting intrauterine growth retardation more than 28 days before birth, were 71 and 81%, respectively. Pulsed Doppler measurements of CCA/UA less than 7 days before the delivery had a sensitivity and specificity of 83 and 90%, respectively. Our results demonstrate the historical change in fetal surveillance within one study group: If accurate routine ultrasound is available, the use of biochemical placental function tests is not justified, a procedure that is already accepted in nearly all perinatal centers. Fetal cerebral versus umbilical blood flow measurements should be applied as a tool to measure fetal blood flow redistribution in small fetuses to predict most precisely the risk for poor outcome and perinatal hypoxia.

Estriol↗

PubMed1998

[Prevention of amblyopia in acute eyelid closure--a new method for keeping the optical axis open by insertion of a small tube].

BACKGROUND: Complete eyelid closure by capillary eyelid hemangioma or ptosis in the first months of life is an indication for acute measures to prevent amblyopia. Since it is sometimes not possible to hold up the affected upper eyelids with adhesive tape (mechanical obstacle, danger of skin maceration in involvement of the forehead) or not sufficiently (intense divergence), an alternative method will be presented for emergency treatment of blockade of the optical axis. METHODS: The eyelids are kept open mechanically with a cylindrical tube of perspex (scleral immersion shell), which is normally used for echography of the anterior segment and for biometry (immersion technique). After surface anesthesia, it can be readily inserted. Its area of contact to the sclera has the form of a scleral shell. A drop of lubricant is applied into the tube at intervals of about five minutes. PATIENTS AND RESULTS: In a six-week-old girl with complete eyelid closure owing to a facial hemangioma, adequate eyelid opening could only be achieved by insertion of the scleral immersion shell. In an eleven-months-old boy with complete ptosis and divergence as well as vertical deviation, the optical axis could only be kept open by insertion of the scleral immersion shell and by simultaneous displacement to the temporal side (adhesive tape). The uncomplicated performance for up to two hours daily was initially carried out in the hospital and later by the parents, and could be terminated after five and three and a half weeks, respectively, thanks to improvement due to therapy or spontaneous improvement. CONCLUSIONS: Mechanical eyelid opening by insertion of a scleral immersion shell serves to bridge over the time interval to the onset of spontaneous improvement or the success of a causal therapy. The advantages consist in the good handling, also for parents, the low danger of injury and the ubiquitous and rapid availability (basic equipment of an ophthalmological ultrasonography unit).

Amblyopia↗

PubMed1998

[Prognosis of keratoplasty in keratitis scrophulosa peracta].

BACKGROUND: In spite of clear transplants the results of keratoplasty are often disappointing. We looked for possible reasons for these failures. PATIENTS AND METHODS: We analyzed in 204 eyes of 115 patients the factors influencing the prognosis. Our results are based on medical records and on demanded reports of the treating ophthalmologists. Patients were divided after different aspects (method of operation, beginning of the disease, operation of the first or second eye). RESULTS: A frequently associated cataract and the method of surgery (aphakia, one- or two-step, triple procedure) has no influence on the prognosis. However, age of onset and density of corneal scars are crucial. This is especially evident in eyes first operated on. In case of early onset (before the age of five) visual acuity only reached 0.21 average postoperatively, whereas patients with late onset gained visual acuity of 0.59. The fellow eye (n = 89) had postoperative visual acuity of 0.48. In patients with poor postoperative visual improvement (< or = two lines) high myopia was apparent in 50%. CONCLUSION: For estimating the prognosis besides early childhood amblyopia we must take into account high myopia induced by formdeprivation (FDM). Exact evaluation of patients' history and preoperative ultrasound biometry are recommended.

Adult↗

PubMed1996

[Clinical experiences after implantation of various lens types in silicon oil tamponade].

BACKGROUND: A tamponade of the vitreous space with silicone oil will obligatory lead to cataract after 6 to 12 months. Today it is easily possible, to implant an artificial lense in silicone oil filled eyes. However the combination of an artificial lense and silicone oil will lead to a strong inflammation in the anterior segment of the eye. PATIENTS AND METHODS: 22 pseudophacic patients with silicone oil tamponade were examined 2 to 6 months after the operation. In 12 patients simple artificial lenses were implanted, in 10 patients heparin modified lenses were implanted. In 10 cases the lens was implanted followed by the insufflation of silicone oil in the vitreous cavity, in 2 cases a lens was implanted in a silicone oil filled eye and the silicon oil was not removed. In 8 cases the implantation of the artificial lens has been performed some months to years before the insufflation of the silicone oil. The indication for the silicon oil tamponade was a PVR retinal detachment in all cases. The following parameters were examined: Reaction of the pupil to light, pupil round or oval in miosis, examination of the fundus peripherie possible after mydriasis, fixation of the iris with parts of the capsula or with the anterior surface of the lens? In addition in 12 cases the postoperative refraction was compared with the results of the biometry, which was performed before the operation. RESULTS: In the cases with a simple lens in about 50% an incomplete miosis or an oval pupil because of fixation of the iris with parts of the capsula or with the anterior surface of the lense could be observed. In the cases with heparin modified lenses these complications could be observed in 20%. In all cases a strong opacification of the capsula was seen. In 8 of 12 cases with combined procedure a small hyperopia was measured, in 4 cases a large deviation was measured. CONCLUSIONS: The implantation of an artificial lens in silicone oil filled eyes is an alternative to the aphacic status with an Ando Iridectomy. Obviously heparin modified lenses have advantages in these cases. Because of the strong cataract formation we suggest to remove the anterior and the posterior capsula in the first operative session and to implant the haptics of the lens into the sulcus. Because of the high rate of complications generally first a stable retina condition should be reached before the implanation of an artificial lens is performed.

Aged↗

PubMed1982

[Incidence and causes of fetal and neonatal macrosomy].

Amongst the 7486 babies born at the Department of Gynecology and Obstetrics in Cologne from 1974 to 1978, 536 neonates displayed a birthweight of more than 4000 g. The obstetrically relevant data from 523 deliveries were evaluated retrospectively. We compared and contrasted the results with a reference group of 511 neonates with a normal weight (2500-3999 g) according to the matched pair principle. The incidence of macrosomic neonates amounted to 7.2% of total deliveries in the observation period. On comparing the average age of the mothers, we found a rise from 27.4 years (mothers of the reference group) to 29.4 years in mothers of babies weighing 4000-4499 g and 30.3 years in mothers with babies weighing 4500 g and more. The proportion of the pregnant mothers over 40 years old was 4.6% as compared to 2% in the reference group in macrosomic babies. The parities show a decrease of the primiparae and an increase of the multiparae amongst mothers of macrosomic babies. The rate of primiparae was 49.3% in the group of babies of normal weight as compared to 33.3% in moderately overweight (4000-4499 g) and 23.4% in the highly overweight babies (4500 g and over). The large proportion of adipose mothers in neonatal macrosomy was also striking. The average weight of the women at the end of pregnancy was 71.4 kg in the reference group and rose to 78.6 or 86.8 kg, respectively, in the mothers of macrosomic neonates. In 453 puerperal mothers who had delivered a macrosomic baby, an oral glucose tolerance test (oGTT) was performed in the first 72 hours after delivery. This was pathological in 25.8% of mothers of moderately overweight children, and was pathological in 29.7% of mothers of distinctly overweight babies. This thus confirmed the correlation between diabetogenic metabolic stress and macrosomy. Evaluation of the course of birth revealed a distinctly raised risk of asphyxia with restriction of the vitality index and increase of abnormal internal and neurological features especially for the neonates with a weight of 4500 g and more. Our goal must therefore be to diagnose macrosomy better than so far by foetal biometry in order to counteract the risks described by prospective control of pregnancy and delivery.

Adult↗

PubMed1991

[Refraction after cataract surgery with posterior chamber lenses].

In an attempt to determine the accuracy of ultrasound biometry, the spherical equivalent of the refraction obtained after ECCE and implantation of a posterior chamber IOL in 1663 patients was compared to the desired refraction determined prior to surgery. Follow up time was 21 months on the average. In only 7.4% of the eyes was the exact predetermined value obtained. In 44.3% it differed toward plus and in 46.6% toward minus. The predetermined value +/- 1 dpt was obtained in 63.8% and +/- 2 dpt in 88.3% of the cases. In 11.7% of the eyes, the desired value was missed by more than +/- 2 dpt.

Eyeglasses↗