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Cyclophotocoagulation is the standard cyclodestructive procedure for treating patients with refractory glaucoma. In addition to transscleral cyclophotocoagulation, endoscopically controlled cyclophotocoagulation (ECPC) is a relatively new method, introduced in the 1990s. Its clinical and technical background is outlined in this article. ECPC allows direct visualization of the ciliary body and better control of the applied laser energy. Therefore, ECPC has been described as being more effective and safer than the transscleral approach. Our own retrospective ECPC data, however, do not indicate that this method can sufficiently decrease intraocular pressure. The indication for the invasive procedure of endoscopic cyclophotocoagulation is therefore questionable.

The Solar System Odyssey mission uses modern-day high-precision experimental techniques to test the laws of fundamental physics which determine dynamics in the solar system. It could lead to major discoveries by using demonstrated technologies. The mission proposes to perform a set of precision gravitation experiments from the vicinity of Earth to the outer Solar System. Its scientific objectives can be summarized as follows: i) test of the gravity force law in the Solar System up to and beyond the orbit of Saturn; ii) precise investigation of navigation anomalies at the fly-bys; iii) measurement of Eddington's parameter at occultations; iv) mapping of gravity field in the outer solar system and study of the Kuiper belt. To this aim, the Odyssey mission is built up on a main spacecraft, designed to fly up to 13 AU, with the following components: a) a high-precision accelerometer, with bias-rejection system, measuring the deviation of the trajectory from the geodesics; b) Ka-band transponders, as for Cassini, for a precise range and Doppler measurement up to 13 AU, with additional VLBI equipment; c) optional laser equipment, which would allow one to improve the range and Doppler measurement. In this baseline concept, the main spacecraft is designed to operate beyond the Saturn orbit, up to 13 AU. It experiences multiple planetary fly-bys at Earth, Mars or Venus, and Jupiter. The cruise and fly-by phases allow the mission to achieve its baseline scientific objectives (i) to iii) in the above list). In addition to this baseline concept, the Odyssey mission proposes the release of the Enigma radio-beacon at Saturn, allowing one to extend the deep space gravity test up to at least 50 AU, while achieving the scientific objective of a mapping of gravity field in the outer Solar System., revision with Experimental Astronomy Referee comments, correction of typographic errors, add of bibliographic reference, modification of authors list

The outflow facility of the glaucomatous eye can be significantly enhanced by opening Schlemm's canal to the anterior chamber. Surgical options for this approach include mechanical procedures, laser surgery, microbipolar cauterization and intracanalicular microstents. Especially in the area of combined cataract-glaucoma surgery these procedures are valuable options owing to their limited intraoperative and postoperative risk profiles. However, trabeculectomy with mitomycin C must still be regarded as the superior surgical option for glaucoma, which requires a low target pressure if combined surgery is unnecessary.

Antiglaucomatous implant surgery is a continously evolving field in glaucoma treatment. A literature search with the terms “glaucoma implant surgery”, “aqueous shunts” and “glaucoma drainage devices” was carried out, especially giving prominence to innovative surgical developments in glaucoma implant surgery and to recently established clinical evidence on traditional shunt surgery. Episcleral glaucoma drainage devices have recently proven their efficacy in large studies. Longterm data about their clinical efficacy and their risk/safety profile are sufficiently available. New antiglaucomatous devices try to target alternative drainage routes, for example trabecular or uveoscleral outflow. Valid longterm data from prospective randomized clinical trials are not available for these devices as yet. Although valid data on clinical application of the new glaucoma implants are not available as yet, profound knowledge about their theoretical concept and their practical management is obligatory for all glaucoma clinicians.

There are few published data on patient satisfaction following glaucoma surgery. The aim of our study was to investigate factors influencing patient satisfaction more than one year after trabeculectomy with mitomycin C.We sent a two-page questionnaire to 61 female glaucoma patients who had consecutively undergone filtering surgery with MMC at the Department of Ophthalmology, University of Cologne, requesting anonymous replies (mean follow-up 19.2+/-2.5 months).The response rate was 79%. There was no significant inverse correlation between patient satisfaction and recent IOP values, redness of the eye, local irritation or foreign body sensation. There was a significant correlation between patient satisfaction and visual function, a significant inverse correlation between frequency of visits to the ophthalmologist and frequency of eye drop application. A weak, insignificant inverse correlation was found between satisfaction and number of topical medications.Patient satisfaction seems to correlate primarily with practical impact on everyday life, visual function, frequency of eye drop application and visits to the eye doctor being identified as the major issues. Local symptoms related to the filtering bleb seem to have a minor influence on patient satisfaction.

Efforts have been directed toward production of efficient, large-area, low-cost photovoltaic modules based on the CdS/CdTe heterojunction, with the objective being to develop an improved materials technology and fabrication process for limited volume production of 1-ft/sup 2/ and 4-ft/sup 2/ CdS/CdTe photovoltaic modules. The present structure of the CdS/CdTe polycrystalline thin-film photovoltaic devices being produced is presented, along with its potential for efficiency improvement. Junction characterization studies are summarized. Module design is described, particularly with regard to encapsulation issue. Future developmental directions are discussed. >

Small intrascleral foreign bodies of different materials, especially plastic or organic, can sometimes not easily--or not at all--be detected by routine X-ray examination or computed tomography scan. The aim of our study was to evaluate the usefulness of ultrasound biomicroscopy (UBM) with regard to the detection and localisation of such foreign bodies.An in vitro study with the preparation of a scleral tunnel on 12 porcine eyes was performed. Small foreign bodies of different types of material were placed in the tunnel. The UBM was performed with a Humphrey Ultrasound Biomicroscope, Model 840, to evaluate its diagnostic value in detecting and specifying these sclera-covered foreign bodies.Even small foreign bodies of the anterior ocular segment of only 200 microm in size can be detected with the UBM due to the typical ultrasound patterns and artifacts. However, there is no diagnostic specificity for the corresponding material.The UBM is a high-frequency ultrasonic device with an imaging depth of 5 mm and a spatial resolution of 100 microm. Therefore it is a useful alternative or, respectively, additional diagnostic tool to common imaging techniques like routine X-ray imaging or CT scans, especially in the detection of non-metallic objects. It can provide important information for the ophthalmic surgeon with regard to pre-operative evaluation of the eye. Furthermore, the UBM might even substitute operative exploration of foreign bodies if they are located in the anterior segment of the eye.

Syphilis is a dangerous sexually transmitted infection which can be effectively treated with penicillin to avoid late-onset diseases. Even if syphilis is diagnosed an HIV infection should be excluded.

Knowledge of individual corneal thickness in individual eyes is proving to be more and more crucial for correcting Goldmann applanation tonometry, as well as to assess its predictive value regarding the possible progression of glaucomatous damage. It has become an important factor in determining appropriate glaucoma therapy. Only few pachymetric data exist about eyes with congenital or secondary pediatric aphakic glaucoma.12 eyes with congenital glaucoma (6 patients, mean age 3.3 years, mean 3.9 previous operations) and 7 eyes with secondary pediatric aphakic glaucoma (4 patients, mean age 14.8 years, mean 3 previous operations) without clinical signs of corneal decompensation were investigated by ultrasound pachymetry.Eyes with glaucoma due to aphakia had a mean corneal thickness of 708 +/- 77.3 microm. Mean corneal thickness of the eyes with congenital glaucoma was 688.1 +/- 115.9 microm, which is far above the values known from the literature. Two eyes, which had a central corneal thickness of 646 microm and 640 microm, presented with a localised paracentral corneal thickness of only 402 microm and 405 microm, respectively, correlating with microscopic descemet scars.Congenital glaucoma and the pediatric aphakic glaucoma present with very heterogeneous clinical pictures. Especially for congenital glaucoma, this is confirmed by the high interindividual, but also intraindividual, variability of corneal pachymetry.

The effect of brimonidine in comparison with acetazolamide on pupillary reflex was investigated in 18 volunteers.Infrared pupillography was performed with white diode light of 200 ms duration to measure pupil diameter, constriction latency, reaction time, constriction amplitude, and relative constriction amplitude. The measurements were performed according to a fixed schedule including a phase without medication to determine the baseline level. Data were analyzed by Student's paired t-test.Application of brimonidine and acetazolamide led to a significantly reduced intraocular pressure as well as static and dynamic differences in the pupillary reflex. The pupil diameter measurements were significantly smaller after both medications in comparison to baseline. The reduction of pupil diameter after brimonidine led to significantly reduced contraction amplitude and prolonged latency.Application of brimonidine leads to significant miosis, which might due to the affinity to alpha(2)-receptors with reduction of noradrenaline release in the synapse. This effect may play a role in a higher decrease of intraocular pressure by increasing aqueous humor outflow in comparison to clonidine and apraclonidine, but further investigations are required.

The goal of this study is the characterization of the strong yellow fluorescence of oxidized melanin in the retinal pigment epithelium (RPE) and the choroid.Naturally occurring melanin in the human retina and choroid was oxidized by exposing fixed and plastic-embedded sections of a human eye to light and hydrogen peroxide. Synthetic melanin was also oxidized in vitro by exposure to light and hydrogen peroxide. The fluorescence of oxidized melanin was examined by absorption spectroscopy, fluorescence spectroscopy, and fluorescence microscopy.Naturally occurring melanin oxidized in situ exhibited a lipofuscin-like yellow fluorescence. Oxidation of melanin in vitro degraded the melanin polymer, resulting in a fluorescent solution. Fluorescence spectroscopy gave an excitation maximum at approximately 470 nm and an emission maximum at approximately 540 nm for both natural and synthetic melanin. Increasing the time of exposure to light or hydrogen peroxide increased melanin fluorescence.The results indicate that the strong yellow fluorescence of melanin in the RPE and choroid in situ is a property of oxidized melanin and is not due to contamination of the melanin by proteinaceous or lipid materials. The data presented allow a reinterpretation of the results obtained from fluorescence investigations of melanin-containing tissue and suggest a link between melanin degradation and lipofuscin formation.

This paper starts by stating that in science there are no facts independent of theory. In psychoanalysis, the theory of the decisive importance of the unconscious makes it possible to grasp clinical facts. This leads to the centrality of transference in analysis. The latter is understood as a social fact. Transference, perceived as a private experience, can be known in the intimacy of the psychoanalytic relationship, through the communication by means of language, which is public. Psychoanalysis is then considered a science of intimacy. The analyst, in publishing clinical facts, faces the problem of the transposition of a fact from the intimacy sphere, considered as private, to the public sphere, and thus serves a scientific purpose. A treatment report is presented to illustrate the problems of the registering, editing and publishing of clinical facts, based on the parallel between making conscious that which is unconscious and making potentially public what is private. Thus the analyst confronts similar difficulties and anxieties, when publishing clinical facts, as the ones that the analysand must overcome to know, through the social experience of psychic intimacy, his or her private inner world.

PURPOSE In vivo imaging of the retina is becoming an increasingly important research method. General anesthesia rapidly compromises the corneal surface, which increases scattering. In addition, wavefront aberrations limit the maximum imaging resolution. Three common methods of stabilizing the air-cornea interface and reducing scattering are the use of a contact lens, a microscopy slide coverslip, or mineral oil. These methods have not yet been analyzed regarding their impact on scattering and wavefront aberrations. METHODS Nineteen eyes of 19 rats were analyzed with a custom-made Hartmann-Shack (HS) wavefront sensor. The amount of scattering was determined by analysis of the HS spot width, and the wavefront was reconstructed for the naked eye and each scattering-reducing method. Their effect on optical quality was determined by calculating the modulation transfer function (MTF). RESULTS The three methods applied significantly reduced scattering but were differentially effective, with the coverslip performing the best and the mineral oil the worst. The root mean square (RMS) of the wavefront aberration, as well as the intereye variability of the RMS, was significantly smaller with the contact lens than with the coverslip. The MTF was best for the contact lens and worst for the coverslip, which was also illustrated by image simulations. CONCLUSIONS The coverslip, contact lens, and mineral oil, when applied to the cornea, all reduced scattering. The best-performing method, the coverslip, increased wavefront aberrations. Overall, the contact lens had the best influence on image quality, and it appears to be the method of choice for high-resolution retinal imaging in rats.

The paper begins with a description of two conceptions of the transference found in the literature: transference as distortion and transference as plausible conjecture based on the signals received by the analysand from the analyst. The plausibility of the transference phenomenon in the Freudian conception of the transference is then reviewed. The author continues by considering the analyst's function as bait and how it is related to the stripping down of reality practised by the analyst. A brief clinical vignette is given to illustrate these propositions. To conclude, there is a discussion of the paradox of the reality sense, the transference and interpretation, based on the ideas of Matte-Blanco, mental functioning being considered in terms of bi-logic.

We review and evaluate the contributions of Mariner 9 in improving our knowledge of the dynamical characteristics of Mars and its two satellites, Phobos and Deimos. Primary results include the discovery of the large gravitational and topographical bulge in the Tharsis region, the development of a detailed gravity model representable as coefficients in a spherical harmonic expansion, the development of a topographic model exhibiting a three kilometer displacement of the center of figure from the center of mass, and the determination of the size, shape and motion of Phobos and Deimos.

Preston et al (1976) and Burke (1982, these proceedings) have long extolled the virtues of launching a radio telescope into space to increase VLBI baseline lengths and thus angular resolution, and to provide a much enhanced image formation capability. The scientific motivation for this has been covered in a number of memoranda referenced by Burke in these proceedings, and by Anderson et al (1982). Efforts to mobilise western astronomical support for space VLBI met with success in late 1982 at a meeting of US and European radio astronomers in Toulouse, France, at which a decision was taken to propose a joint mission to ESA and NASA. Shortly thereafter, a formal proposal was made to ESA (Anderson et al 1982) for a free flying satellite in an elliptical orbit out to 15000 km from the Earth, designed to observe in concert with the major ground-based VLBI networks and arrays. The mission, dubbed QUASAT, was received favourably in both ESA and NASA, with the result that formal Assessment Studies are scheduled to begin in both agencies in October 1983.

Analysis of the Mariner 9 radio-tracking data shows that the Martian gravity field is rougher than that of Earth or the moon, and that the accepted direction of Mars's rotation axis is in error by about 0.5°. The new value for the pole direction for the epoch 1971.9, referred to the mean equatorial system of 1950.0, is right ascension α = 317.3° ± 0.3°, declination δ = 52.6° ± 0.2°. The values found for the coefficients of the low-order harmonics of Mars's gravity field are as follows: J 2 =(1.96±0.01) × 10 -3 , referred to an equatorial radius of 3394 kilometers; C 22 = -(5 ± 1) × 10 -5 ; and S 22 = (3 ± 1) × 10 -5 . The value for J 2 is in excellent agreement with the result from Wilkins' analysis of the observations of Phobos. The other two coefficients imply a value of (2.5 ± 0.5) × 10 -4 for the fractional difference in the principal equatorial moments of inertia; the axis of the minimum moment passes near 105°W.

The 'Pathfinder' project uses the resources of NASA, ESA and Intercosmos to support the Giotto space probe flyby of comet Halley. The required 500-km approach to comet Halley on the sunward side was so uncertain as to preclude the trajectory's realization with sufficient accuracy on the basis of ground-based astronomical observations alone. Spaceborne observations by the two Vega satellites were accordingly conducted; these, in combination with a very accurate determination of the Vega trajectories using VLBI, allowed a flyby distance of 600 km to be achieved with only + or - 40 km uncertainty.

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An international fleet of five spacecraft will fly past Comet Halley as it travels through the inner solar system in early 1986. This paper discusses orbit determination problems associated with the Giotto spacecraft, sponsored by the European Space Agency. The large number of spin axis precession maneuvers required to maintain the desired spacecraft attitude creates a new kind of radio metric orbit determination problem for this mission. This paper investigates the accuracy with which the Giotto spacecraft orbit can be determined relative to the earth or the sun, and establishes the sensitivity of this accuracy to the selection of the parameters to be estimated, the form of estimator used, the number of tracking stations employed, the length of the data arc, the selection of data types processed, and the levels of various error sources.

An orbiting spacecraft and ground observatories have been used to obtain interferometric observations of cosmic radio sources. The Tracking and Data Relay Satellite System (TDRSS) was used as the orbiting observatory in conjunction with two 64- meter radio telescopes at ground observatories, one in Australia and one in Japan. The quasars 1730-130 (NRAO 530), 1510-089, and 1741-038 were observed at a frequency of 2.3 gigahertz, and a maximum projected baseline of 1.4 earth diameters was achieved. All quasar observations for which valid data were acquired resulted in detected fringes. Many of the techniques proposed for a dedicated very long baseline interferometry observatory in space were used successfully in this experiment.

While current VLBI observations are limited in their resolution by the earth diameter magnitude, which is the largest antenna separation available, as well as in their information content, because of the small number of antennas in use at a given time, the extension of VLBI to include one or more antennas in space will relieve both constraints and help to map distant radio sources with the highest possible resolution. Attention is given to the implementation of such an orbital VLBI system extension through (1) a Shuttle-launch mission, (2) a six-month to one-year near earth orbit mission based on a space platform associated with the Space Station, (3) a large orbit free flyer platform mission of more than 2-year duration, and (4) lunar and/or deep space orbits, aimed at reaching the resolution limits set by interstellar scattering.

Navigation, for interplanetary space flight, is defined as the process of determining the position and predicted flight path of a spacecraft and correcting that flight path to achieve the mission objectives. The space navigation process involves a sequence of actions: the acquisition of radio tracking and optical measurements, the determination of a best statistically estimated orbit based on the measurements, and the computation of the trajectory-correcting spacecraft maneuvers.

Preflight error statistics of earth based Doppler tracking for Mariner navigation concerning Mars 1971 and Venus-Mercury 1973 missions

Earth based orbit determination for Mars orbiting spacecraft, comparing batch and sequential tracking filter data processing methods

This paper presents the results of the applications of advanced filtering methods to the determination of the interplanetary orbit of the Mariner '71 spacecraft. The advanced techniques are specific extensions of the Kalman filter. The special problems associated with applying these techniques are discussed and the particular algorithmic implementations are outlined. The advanced methods are compared against the weighted least squares filters of conventional application. The results reveal that relatively simple advanced filter configurations yield solutions superior to those of the conventional methods when applied to the Mariner '71 radio measurements.

Background To evaluate the success rate and adverse effects of Gold Micro Shunt Plus (GMS+) implantation into the supraciliary space. Methods This retrospective study included 31 eyes of 31 patients diagnosed with severe glaucoma and uncontrolled intraocular pressure (IOP) with implantation of a GMS+ by means of a full-thickness scleral flap. The main outcome measures were surgical failure or success, based on the intraocular pressure and adverse effects. Clinical examination data are reported up to 4 years postoperatively. Results Thirty eyes (97%) met one of our criteria for failure. Within a mean of 7.3 ± 7.7 months another surgery was performed because of elevated IOP in 24 of 31 eyes (77%) and because of adverse effects in 2 (6%). The remaining 4 eyes, that met one of our criteria for failure, had an IOP reduction of less than 20% with comparable medication. Six GMS+’s were explanted; because of IOP elevation, 2; rubeosis iridis, 2; and low grade inflammation, 2. Conclusions GMS+ implantation is not an effective method to control IOP in patients with glaucoma, when using our surgical technique. The reason for the found signs of chronic low grade inflammation or rubeosis iridis in 4 eyes (13%) remains unknown and has to be further investigated.

During the summer of 1976, the two Viking spacecraft, each consisting of an orbiter-lander combination, were inserted into orbit about Mars. The paper describes the experiences of the Viking Satellite Orbit Determination Team in determining Mars centered ephemerides of the orbiters and positions of the landers from the two-way Doppler and range data, and synthesizes the different phases of the navigation plan which involves pre-flight modeling and error analysis for all Viking navigation functions from launch through landing. The problem of initial orbit convergence is solved by using DPODP's (Double Precision Orbit Determination Program) square-root batch data filter, and gravity models for both Viking I and Viking II were produced from the combination of short arc estimates. The importance of synchronous Viking orbits (with the rotational period of Mars) is stressed and future extended missions of the spacecraft are outlined.

A new electronic organ operating on the formant principle is described. Sawtooth wave forms are generated in a vacuum tube generator and are modified by a variety of filter circuits to provide desired tone colors. Modified square wave forms are also utilized for certain effects. There are twelve tuning adjustments, each controlling one of the frequencies in the top octave. All notes in the lower octaves are obtained by frequency division in the ratio of 2 to 1. A frequency vibrato is used. Keying transients are eliminated by the use of graduated resistance type switches.