[Timing of congenital cataract surgery : Amblyopia versus aphakic glaucoma]. / Operationszeitpunkt der kongenitalen Katarakt : Zwischen Amblyopie und Aphakieglaukom.

A congenital cataract is a rare disorder, which is associated with a high risk of amblyopia. Ophthalmologists are faced with many diagnostic and surgical challenges in the management of this disease. Older children can undergo primary treatment with an intraocular lens, whereas children younger than 12 months of age usually initially remain aphakic. The most frequent long-term complication of aphakic eyes following congenital cataract surgery in connection with posterior capsulorrhexis and anterior vitrectomy is aphakic glaucoma, which in individual cases can lead to substantial impairment of vision. Many factors have been reported to increase the risk of postoperative glaucoma, including microphthalmos, fetal nuclear cataract, conspicuous family history and associated ocular malformations, such as persistent fetal vasculature (PFV). Cataract surgery during early infancy is well-established to be the most important factor for the formation of postoperative aphakic glaucoma. In individual treatment planning it has to be considered that although younger age at the time of cataract removal can provide better prerequisites for prophylaxis of amblyopia, it also confers a higher risk of development of aphakic glaucoma. Children undergoing congenital cataract surgery have to be regularly monitored given the lifelong risk for postoperative complications, such as aphakic glaucoma.

[Impact of timing of surgery on outcome in children with bilateral congenital cataract]. / Bilaterale kongenitale Katarakt: Klinische und funktionelle Ergebnisse in Abhängigkeit vom Operationszeitpunkt.

BACKGROUND: The optimal time for surgical intervention in bilateral congenital cataract is still a matter of controversy. OBJECTIVES: Herein, we evaluated clinical and functional results after bilateral congenital cataract surgery and performed subgroup analysis based on the age at the time of surgery. MATERIALS AND METHODS: We retrospectively reviewed the records of 52 eyes of 26 children who underwent surgery for bilateral congenital cataract without intraocular lens implantation within the first 12 months of life; 16 eyes underwent phacoaspiration within the first 10 weeks of life (group A) and 26 eyes had cataract extraction at an age of >10 weeks (group B). We defined the primary outcome measure to be the prevalence of mild, moderate, and severe amblyopia in relationship to age-dependent visual acuity norms after a mean follow-up of 59.7 ± 43.2 months. Secondary outcome measures were interocular difference of visual acuity and the presence of strabismus, nystagmus, posterior capsule opacification, and aphakic glaucoma. RESULTS: The prevalence of amblyopia was not statistically different between the two age groups. Of all children, 62.5 % (A) and 61.1 % (B) developed age-dependent normal visual acuity or mild amblyopia. However, the younger cohort developed significantly less strabismus than the older cohort (P = 0.03). There was a strong relationship between cataract surgery within the first 14 weeks of life and the development of aphakic glaucoma. All children developing secondary cataract formation underwent cataract surgery in the first 20 weeks of life. CONCLUSIONS: Our results suggest that long-term prevalence of mild, moderate, and severe amblyopia is similar between the two cohorts of bilateral congenital cataract eyes based on the age ≤ or >10 weeks at the time of surgery. Because there is a strong relationship between postoperative complications and a young age at the time of cataract surgery, close postoperative follow-up is essential. Strabismus is less likely to develop in infants after bilateral cataract surgery within the first 10 weeks of life.

Phosphocholine - an agonist of metabotropic but not of ionotropic functions of α9-containing nicotinic acetylcholine receptors.

We demonstrated previously that phosphocholine and phosphocholine-modified macromolecules efficiently inhibit ATP-dependent release of interleukin-1ß from human and murine monocytes by a mechanism involving nicotinic acetylcholine receptors (nAChR). Interleukin-1ß is a potent pro-inflammatory cytokine of innate immunity that plays pivotal roles in host defence. Control of interleukin-1ß release is vital as excessively high systemic levels cause life threatening inflammatory diseases. In spite of its structural similarity to acetylcholine, there are no other reports on interactions of phosphocholine with nAChR. In this study, we demonstrate that phosphocholine inhibits ion-channel function of ATP receptor P2X7 in monocytic cells via nAChR containing α9 and α10 subunits. In stark contrast to choline, phosphocholine does not evoke ion current responses in Xenopus laevis oocytes, which heterologously express functional homomeric nAChR composed of α9 subunits or heteromeric receptors containing α9 and α10 subunits. Preincubation of these oocytes with phosphocholine, however, attenuated choline-induced ion current changes, suggesting that phosphocholine may act as a silent agonist. We conclude that phophocholine activates immuno-modulatory nAChR expressed by monocytes but does not stimulate canonical ionotropic receptor functions.

[Occlusion treatment for amblyopia. Age dependence and dose-response relationship]. / Okklusionstherapie bei Amblyopie. Altersabhängigkeit und Dosis-Wirkungs-Beziehung.

BACKGROUND: Based on clinical experience and studies on animal models the age of 6-7 years was regarded as the limit for treatment of amblyopia, although functional improvement was also occasionally reported in older patients. New technical developments as well as insights from clinical studies and the neurosciences have attracted considerable attention to this topic. OBJECTIVE: Various aspects of the age dependence of amblyopia treatment are discussed in this article, e. g. prescription, electronic monitoring of occlusion dosage, calculation of indicators for age-dependent plasticity of the visual system, and novel, alternative treatment approaches. METHODS: Besides a discussion of the recent literature, results of studies by our "Child Vision Research Unit" in Frankfurt are presented: results of a questionnaire about prescription habits concerning age limits of patching, electronic recording of occlusion in patients beyond the conventional treatment age, calculation of dose-response function and efficiency of patching and their age dependence. RESULTS: The results of the questionnaire illustrate the uncertainty about age limits of prescription with significant deviations from the guideline of the German Ophthalmological Society (DOG). Electronic recording of occlusion allowed the quantification of declining dose-response function and treatment efficiency between 5 and 16 years of age. Reports about successful treatment with conventional and novel methods in adults are at variance with the notion of a rigid adult visual system lacking plasticity. CONCLUSION: Electronic recording of patching allowed new insights into the age-dependent susceptibility of the visual system and contributes to a more evidence-based treatment of amblyopia. Alternative approaches for adults challenge established notions about age limits of amblyopia therapy. Further studies comparing different treatment options are urgently needed.

Comparison of optotypes of Amsterdam Picture Chart with those of Tumbling-E, LEA symbols, ETDRS, and Landolt-C in non-amblyopic and amblyopic patients.

PURPOSE: To compare optotypes of the Amsterdam Picture Chart (APK) with those of Landolt-C (LC), Tumbling-E (TE), ETDRS and LEA symbols (LEA), to assess their reliability in measuring visual acuity (VA). METHODS: We recruited healthy controls with equal VA and amblyopes with ≥2 LogMAR lines interocular difference. New logarithmic charts were developed with LC, TE, ETDRS, LEA, and APK with identical size and spacing (four optotypes) between optotypes. Charts were randomly presented at 5 m under DIN EN ISO 8596 and 8597 conditions. VA was measured with LC (LC-VA), TE, ETDRS, LEA, and APK, using six out of ten optotypes answered correctly as threshold. RESULTS: In 100 controls aged 17-31, LC-VA was -0.207 ± SD 0.089 LogMAR. Visual acuity measured with TE differed from LC-VA by 0.021 (positive value meaning less recognizable), with ETDRS 0.012, with Lea 0.054, and with APK 0.117. In 46 amblyopic eyes with LC-VA <0.5 LogMAR, the difference was for TE 0.017, for ETDRS 0.017, for LEA 0.089, and for APK 0.213. In 13 amblyopic eyes with LC-VA ≥0.5 LogMAR, the difference was for TE 0.122, ETDRS 0.047, LEA 0.057, and APK 0.019. APK optotypes had a lower percentage of passed subjects at each LogMAR line compared to Landolt-C. The 11 APK optotypes had different thresholds. CONCLUSIONS: Small APK optotypes were recognized worse than all other optotypes, probably because of their thinner lines. Large APK optotypes were recognized relatively well, possibly reflecting recognition acuity. Differences between the thresholds of the 11 APK optotypes reduced its sensitivity further.

The gasotransmitter hydrogen sulphide decreases Na⁺ transport across pulmonary epithelial cells.

BACKGROUND AND PURPOSE The transepithelial absorption of Na(+) in the lungs is crucial for the maintenance of the volume and composition of epithelial lining fluid. The regulation of Na(+) transport is essential, because hypo- or hyperabsorption of Na(+) is associated with lung diseases such as pulmonary oedema or cystic fibrosis. This study investigated the effects of the gaseous signalling molecule hydrogen sulphide (H(2) S) on Na(+) absorption across pulmonary epithelial cells. EXPERIMENTAL APPROACH Ion transport processes were electrophysiologically assessed in Ussing chambers on H441 cells grown on permeable supports at air/liquid interface and on native tracheal preparations of pigs and mice. The effects of H(2)S were further investigated on Na(+) channels expressed in Xenopus oocytes and Na(+) /K(+)-ATPase activity in vitro. Membrane abundance of Na(+) /K(+)-ATPase was determined by surface biotinylation and Western blot. Cellular ATP concentrations were measured colorimetrically, and cytosolic Ca(2+) concentrations were measured with Fura-2. KEY RESULTS H(2)S rapidly and reversibly inhibited Na(+) transport in all the models employed. H(2)S had no effect on Na(+) channels, whereas it decreased Na(+) /K(+)-ATPase currents. H(2)S did not affect the membrane abundance of Na(+) /K(+)-ATPase, its metabolic or calcium-dependent regulation, or its direct activity. However, H(2)S inhibited basolateral calcium-dependent K(+) channels, which consequently decreased Na(+) absorption by H441 monolayers. CONCLUSIONS AND IMPLICATIONS H(2) S impairs pulmonary transepithelial Na(+) absorption, mainly by inhibiting basolateral Ca(2+)-dependent K(+) channels. These data suggest that the H(2)S signalling system might represent a novel pharmacological target for modifying pulmonary transepithelial Na(+) transport.

[Electronically recorded occlusion treatment in amblyopes older than 7 years: acuity gain after more than 4 months of treatment?]. / Elektronisch erfasste Okklusionstherapie bei über 7-jährigen Amblyopen: Visusanstieg noch nach mehr als 4 Monaten?

BACKGROUND: According to the ROTAS study most of the improvement in visual acuity (VA) during amblyopia therapy of children aged 3 to 8 years occurs during the first 6 to 8 weeks . Sattler reported a VA gain in 11-year olds even during the second year of treatment . So far there are no standards concerning the intensity and duration of the treatment of patients older than 7 years of age. After a report on electronic monitoring of occlusion treatment in patients aged 7 to 16 years for 4 months , we now analyse whether this age group benefits from a longer-lasting treatment. MATERIALS AND METHODS: In this pilot study the progression of VA was analysed in 11 patients (age range 7.18 to 15.76 years; median 11.42 years) during 12 months of occlusion therapy (types of amblyopia: 5 anisometropic, 1 strabismic, 5 combined). The daily occlusion times were recorded using the occlusion dose monitor (ODM) . At the beginning of treatment the prescription of the occlusion regime (median) was 6 h/d (range 4 to 7 h/d), the (decimal) VA 0.2 (range 0.02 to 0.63) for single and 0.16 (range 0.02 to 0.8) for crowded optotypes. RESULTS: The recorded occlusion time (median) was 4.4 h/d during the 12 months of treatment, the VA gain (median) was 0.4 log units for single (range 0.2 to 0.7 log units) and 0.3 for crowded optotypes (range--0.1 to 0.6). During the period of 4 to 12 months of treatment (received occlusion 4.12 h/d) the VA gain was 0.1 log units for single and for crowded optotypes. The maximum VA gain during the interval of 4 to 12 months of treatment was 0.2 log units, both single and crowded. The interocular difference for crowded VA (median) decreased from 0.9 to 0.6 log units during treatment, however only one patient achieved an interocular difference of < 0.2 log units. CONCLUSION: The patients presented here were able to integrate daily occlusion lasting several hours and the electronic monitoring of occlusion treatment into their daily routine over a period of 12 months. During this period the VA of all included types of amblyopia improved significantly, both from a clinical and statistical point of view. Further long-term studies using ODMs with larger groups of patients may identify factors for success of treatment, reveal the long-term stability of the improvement and contribute to a standardised treatment in this age group.

Psychological causes of non-compliance with electronically monitored occlusion therapy for amblyopia.

AIM: To analyse psychological causes for low compliance with occlusion therapy for amblyopia. METHOD: In a randomised trial, the effect of an educational programme on electronically measured compliance had been assessed. 149 families who participated in this trial completed a questionnaire based on the Protection Motivation Theory after 8 months of treatment. Families with compliance less than 20% of prescribed occlusion hours were interviewed to better understand their cause for non-compliance. RESULTS: Poor compliance was most strongly associated with a high degree of distress (p<0.001), followed by low perception of vulnerability (p = 0.014), increased stigma (p = 0.017) and logistical problems with treatment (p = 0.044). Of 44 families with electronically measured compliance less than 20%, 28 could be interviewed. The interviews confirmed that lack of knowledge, distress and logistical problems resulted in non-compliance. CONCLUSION: Poor parental knowledge, distress and difficulties implementing treatment seemed to be associated with non-compliance. For the same domains, the scores were more favourable for families who had received the educational programme than for those who had not.

[Spontaneous improvement of visual acuity in adult amblyopia after functional loss in the non-amblyopic eye?]. / Spontane Visusbesserung bei amblyopen Erwachsenen nach Funktionsverlust des Führungsauges?

BACKGROUND: The prognosis of functional improvement after vision loss in the non-amblyopic eye in adulthood is important for counselling of the patients, but uncertain for a number of reasons. Our study focuses on two aspects. Firstly, a questionnaire was developed asking ophthalmologists and orthoptists for their opinion about the chances of significant spontaneous improvement; secondly, patient data were analysed with respect to acuity data acquisition and documentation as reasons for uncertainty concerning the prognosis. MATERIALS AND METHODS: In the context of a project about age limits of amblyopia treatment, a questionnaire was developed which comprised also an item about the estimation of the prognosis after loss of vision in the non-amblyopic eye. It was distributed to ophthalmologists and orthoptists, and the answers were analysed in connection with two large, published studies about this topic . Furthermore, acuity data of three adult amblyopes were analysed after loss of function in the non-amblyopic eye. RESULTS: The questionnaire was answered by 109 ophthalmologists and 128 orthoptists, all working in Germany. Almost 50% of the answers concerning the chances of spontaneous improvement were in agreement with the data of the two published studies, which stated that the chances of spontaneous improvement were 10% or 17.4%, respectively. More than 25% of the answers underestimated the chances for spontaneous improvement (answer: 0 to 5%). On the other hand, a number of orthoptists and ophthalmologists estimated the chances much too optimistically, some anticipating more than a 60% chance of spontaneous improvement. The analysis of the patient data showed that both acquisition and documentation of acuity data gave reasons for uncertainties concerning the prognosis for visual acuity. CONCLUSIONS: In addition to new ways of assessing treatment compliance and quality of life, knowledge about the opinion of the treating personnel concerning various aspects of a disease may lead to more evidence-based treatment. In amblyopic patients, the inclusion of certain details into the documentation (type and separation of the optotypes, optical correction) may be essential.

["Fragebogen zum Kindlichen Sehvermögen (FKS)". Assessment of quality of life with the German version of the Children's Visual Function Questionnaire]. / Fragebogen zum Kindlichen Sehvermögen (FKS). Die deutsche Version des "Children's Visual Function Questionnaire"--ein Instrument zur Erfassung der Lebensqualität sehbeeinträchtigter Kinder.

BACKGROUND: The assessment of quality of life plays an increasing role in ophthalmology. Standardized questionnaires such as the National Eye Institute Visual Function Questionnaire (NEI-VFQ) are useful instruments to evaluate the impact of ophthalmological diseases on the quality of life in adults. In children and infants, different instruments are needed, partly because of the changing developmental stages with age. Felius and colleagues developed a questionnaire to assess the quality of life in young children with visual impairment, the Children's Visual Function Questionnaire (CVFQ). It was validated in the United States. Our aim was to translate and adapt the questionnaire to make it applicable for the German-speaking countries. METHODS: Two independent groups in the ophthalmology departments of the University of Frankfurt and the University of Freiburg translated the questionnaire into German. In cooperation with the authors of the CVFQ, a consensus adaptation was created, which was then reexamined by the two German groups to establish the adaptation presented here. RESULTS: The German adaptation, like the original instrument, exists in two versions, one for infants and children <3 years of age and one for children > or =3 years. Besides vision and general health, the questionnaire assesses the following quality-of-life domains: competence, personality, family impact, and treatment. The first data for patients with an ophthalmological diagnosis (amblyopia and occlusion treatment, and aphakia with contact lens treatment) were collected and compared with data of children without visual impairment. CONCLUSION: The translated CVFQ provides an instrument for those in German-speaking countries to assess the quality of life in visually impaired children. The data sample shows its applicability for assessing the influence of diseases of the visual system and their treatment on the patients' and families' lives.

[Visual distortions and depersonalization-de-realization syndrome]. / Gestörte visuelle Wahrnehmung beim Depersonalisations-Derealisationssyndrom.

Disturbances of visual perception like micropsia, macropsia, teleopsia, pelopsia, metamorphopsia or loss of stereoscopic depth perception are usually considered in ophthalmology as symptoms of retinopathy, especially maculopathy or disorders of binocularity. Differential diagnostic considerations include disorders like migraine and epilepsy but not the visual disturbance pertaining to the depersonalization-de-realization syndrome, although the above-mentioned symptoms are more prevalent in this psychogenic disorder. This article gives a review of depersonalization-de-realization in order to enable the ophthalmologist to include this syndrome into his diagnostic considerations.

[Adaptation of visual distortions in children with strabismic amblyopia following strabismus surgery and occlusion therapy]. / Dynamik der visuellen Wahrnehmungsverzerrungen bei Kindern mit Schielamblyopie unter dem Einfluss von Schieloperation und Okklusionstherapie -- Amblyopietherapie und Fehllokalisation.

BACKGROUND: Reduced visual acuity and deficient binocularity are well-known symptoms of amblyopia. Distortions of visual space perception were reported more recently in strabismic amblyopia. This study investigated whether strabismus surgery and occlusion therapy have an influence on these deficits in amblyopic children. MATERIALS AND METHODS: Two aspects of vertical alignment of amblyopic eyes, namely spatial distortion and spatial uncertainty, were investigated prospectively in 13 children (mean age 6 years 9 months) before and after strabismus surgery and in 12 children (mean age 6 years 11 months) during 6 months of occlusion therapy. RESULTS: A different impact of the two types of therapeutic intervention was observed: a slight (statistically not significant) increase of uncertainty was the only change noticed postoperatively after 1 week, spatial distortions were not affected. During occlusion treatment, both clear shifts of alignment and a decrease of uncertainty occurred. CONCLUSIONS: The geometry of visual space of amblyopic children showed modifications due to altered visual experience during treatment, most obviously during occlusion therapy. These changes are evidence for unknown features of plasticity of the amblyopic visual system initiated by treatment.

Transport of sodium and chloride across earthworm skin in vitro.

We present a new invertebrate model for the study of epithelial sodium transport in tight epithelia, the earthworm integument. Dissected segments of earthworm integument were mounted in modified Ussing chambers and perfused with either pond water (PW) or earthworm ringer solution (ERS) on the apical side. In order to investigate ion transport under near-in vivo physiological conditions, measurements were performed under current-clamp conditions by monitoring the transepithelial potential (V (T)), as well as the transepithelial resistance (R (T)). These were recorded continuously and the virtual short circuit current (I (SC)) was calculated. The integument has a high transepithelial resistance (R (T) = 9,037 +/- 502 Omega cm(2) for PW, n = 24, and 11,055 +/- 1,320 Omega cm(2) for ERS, n = 32). V (T) was -3.7 +/- 2.2 mV for PW (n = 24) and -1.5 +/- 1.0 mV for ERS (n = 32), and I (SC) was -0.57 +/- 0.30 microA/cm(2) for PW (n = 24) and -0.44 +/- 0.24 microA/cm(2) for ERS (n = 32). Only under PW, but not under ERS conditions, was there a pronounced inhibition of I (SC) by low doses of amiloride or its analogues phenamil and benzamil. The resistance of the paracellular pathway was found to be very high. The terrestrial oligochaete Lumbricus seems especially adapted to the environmental conditions because it has an ultra-tight integument and a very fast up- and down-regulation of apical Na(+) channels.

Prostaglandin E2 induces upregulation of Na+ transport across Xenopus lung epithelium.

The apical mucus on pulmonary epithelia is not only critical for physiological functions such as gas exchange or inflammatory processes, but also contains surfactants and multiple molecules that mediate cellular responses. A tight control of transepithelial ion transport maintains viscosity of this layer and, e.g., the amiloride-sensitive sodium channels (ENaCs) in lung epithelia of vertebrates are the most important regulatory sites for transcellular sodium uptake. Dysfunction of this sodium transport results in reduced liquid absorption and causes massive problems with gas exchange. We used dissected lungs of Xenopus laevis in Ussing chambers to investigate the influence of prostaglandin E2 (PGE2) on the regulation of short-circuit current (ISC) and amiloride-sensitive sodium absorption (Iami). Apical application of PGE2 (1 microM) increased ISC by 38% and Iami by approximately 60%. In contrast, a different prostaglandin, PGI2, neither affected ISC nor Iami. Forskolin increased current to a similar magnitude and preincubation of the lung with an RP-isomer of cyclic AMP, an inhibitor of protein kinase A (PKA), abolished the effects of both PGE2 and forskolin. Transepithelial Na+ uptake was also upregulated by the prostaglandin receptor agonists misoprostol and sulprostone. The Iami in Xenopus oocytes that heterologously expressed ENaCs was not affected by PGE2.

Stimulation of transepithelial Na(+) current by extracellular Gd(3+) in Xenopus laevis alveolar epithelium.

In the present study we investigated the effect of extracellular gadolinium on amiloride-sensitive Na(+) current across Xenopus alveolar epithelium by Ussing chamber experiments and studied its direct effect on epithelial Na(+) channels with the patch-clamp method. As observed in various epithelia, the short-circuit current ( I(sc)) and the amiloride-sensitive Na(+) current ( I(ami)) across Xenopus alveolar epithelium was downregulated by high apical Na(+) concentrations. Apical application of gadolinium (Gd(3+)) increased I(sc) in a dose-dependent manner ( EC(50) = 23.5 microM). The effect of Gd(3+) was sensitive to amiloride, which indicated the amiloride-sensitive transcellular Na(+) transport to be upregulated. Benz-imidazolyl-guanidin (BIG) and p-hydroxy-mercuribenzonic-acid (PHMB) probably release apical Na(+) channels from Na(+)-dependent autoregulating mechanisms. BIG did not stimulate transepithelial Na(+) currents across Xenopus lung epithelium but, interestingly, it prevented the stimulating effect of Gd(3+) on transepithelial Na(+) transport. PHMB increased I(sc) and this stimulation was similar to the effect of Gd(3+). Co-application of PHMB and Gd(3+) had no additive effects on I(sc). In cell-attached patches on Xenopus oocytes extracellular Gd(3+) increased the open probability ( NP(o)) of Xenopus epithelial sodium channels (ENaC) from 0.72 to 1.79 and decreased the single-channel conductance from 5.5 to 4.6 pS. Our data indicate that Xenopus alveolar epithelium exhibits Na(+)-dependent non-hormonal control of transepithelial Na(+) transport and that the earth metal gadolinium interferes with these mechanisms. The patch-clamp experiments indicate that Gd(3+) directly modulates the activity of ENaCs.

[Some aspects of the current controversy about the treatment of amblyopia]. / Amblyopietherapie in der Diskussion.

Occlusion has been used for centuries for treating amblyopia but in recent years an intensive debate about the treatment has arisen. The aim of this article is to summarize some of the new aspects of this discussion: on the one hand the effect of occlusion treatment during childhood is being questioned and on the other hand experimental approaches are being tested which are aimed at treating amblyopia in adults. Evidence from own experimental work is presented showing the influence of occlusion on the spatial localization of visual stimuli. A continuation of research on amblyopia and the effect of the therapy is urgently needed.

Inhibitory non-genomic effects of progesterone on Na+ absorption in epithelial cells from Xenopus kidney (A6).

The effect of the steroid hormone progesterone on transepithelial sodium transport was measured in confluent monolayers of the A6-cell line from Xenopus kidney. Apical permeabilization with Amphotericin B enabled us to measure the Na+/K+-pump current, and current-fluctuation analysis was used to analyze changes in apical channel density and gating characteristics. Basolateral progesterone (22.2 microM) had a rapid inhibitory effect on the Na+/K+-pump current, and a corresponding decrease in Na+ channel density. The effect occurred within some minutes and took about 50 min to reach a new steady state, in which 45% of the macroscopic current (ISC) was inhibited. Progesterone also inhibits the hypo-osmotic stimulation of Na+ channels which occurs in untreated monolayers. Compared with the known effects of adrenal steroids, our results show a rapid inhibitory action of a steroid hormone on Na+ absorption. The time profile of the progesterone effect suggests, at least in the first minutes, a non-genomic action of progesterone.

[Contrast media-enhanced 3D MR angiography before endovascular treatment of aneurysm in the abdominal aorta, iliac artery and peripheral vessels]. / Kontrastmittelverstärkte 3D-MR-Angiographie vor endoluminaler Therapie von Aneurysmen der Aorta abdominalis und der Becken-Bein-Strombahn.

PURPOSE: The value of DSA for the measurement of aortic and peripheral arterial aneurysm dimensions before endovascular treatment is limited by projection effects. It was evaluated if additional gadolinium-enhanced three-dimensional MR angiography (3D-CEMRA) could compensate for the disadvantages of DSA. MATERIALS AND METHODS: 21 patients with 35 aneurysms in the abdominal aorta (14), iliac (9) and femoropopliteal vessels (12) were assessed with DSA (7 with calibrated catheter, 14 with yardstick) and 3D-CEMRA (TR/TE 7.8/2.1 ms, flip-angle 40 degrees, Matrix 512 x 224, FOV 500 mm, eff. slice 1.8 mm). We measured and compared aneurysm dimensions on both modalities. 3D-CEMRA was regarded as the reference method to evaluate the dimension of DSA-projection effects. RESULTS: Diameter and length of aneurysms were underestimated on DSA with the yardstick as reference. The deviation ranged from 15% (+/- 5%) in the aorta to 21% (+/- 10%) in the iliac vessels. Only with calibrated catheters as reference (7/21 DSA), were the distances on DSA correlated well with MRA. In 2/35 aneurysms 3D-CEMRA detected thrombosis with difference between length of inner lumen dilatation on DSA and whole aneurysm length. 2/5 accessory renal arteries found on DSA were not detected on 3D-CEMRA. CONCLUSIONS: 3D-CEMRA is a valuable adjunct to DSA for pre-interventional diagnostics of aortic and peripheral arterial aneurysms. It provides exact evaluation of aneurysm dimensions and information about partial thrombosis.

Preliminary report: monocular spatial localization in children with strabismic amblyopia.

Defective spatial localization is an important feature of strabismic amblyopia. Based on our experience from testing adult strabismics under various test conditions, we developed a test for assessing vertical alignment in strabismic children. Patients had to align a vertical test line with the apices of two vertically arranged reference triangles, under the control of both the dominant eye and the amblyopic eye. Means and standard deviations of several judgements represent systematic errors and uncertainty of alignment. We tested 27 strabismic and 34 age-matched control children aged 4.5-10 years. Control children showed a scatter of mean systematic alignment around the correct position of up to 7 minarc. In the amblyopic eyes of strabismic children, uncertainty was consistently higher than in the eyes of the control children. Systematic errors outside the normal range frequently occurred. In children tested repeatedly during occlusion therapy, uncertainty decreased as visual acuity improved. In several cases we observed changes of systematic vertical alignment during therapy, sometimes unexpectedly in the sense of a change in the direction of mislocalization or an initial increase and later decrease of errors. Thus, children with strabismic amblyopia show spatial localization deficits which are similar to those of adult strabismic amblyopes. Both spatial uncertainty and systematic distortions are susceptible to change due to enforced use of the amblyopic eye during occlusion therapy.

The development of visual acuity in the peripheral visual field of human infants: binocular and monocular measurements.

We measured binocular and monocular grating acuity in the peripheral visual field of infants, using a modified preferential looking procedure. Both binocular and monocular peripheral acuity increased between 2 and 11 months of age, but had not reached adult levels at the end of the first year of life. Binocular acuity was always higher than monocular acuity. At all ages tested, acuity was higher in the temporal than in the nasal visual field. We conclude that, in spite of the relative morphological maturity of the peripheral retina, visual acuity develops in the peripheral visual field.