Preliminary results of course dynamics of visual acuity in patients with non-object vision

Purpose. This paper presents the results of the first human trial on the correction of hyperopia using an erodible mask excimer laser delivery system coupled to an axicon. Methods. We treated 17 eyes of 17 patients (age range 34–62 years) for the correction of +3.21 ± 1.04 D (range +1.00 to +4.00 D). The hyperopic correction was made using an erodible mask inserted on the laser optical pathway, to produce a circular ablation measuring 6.5 mm in diameter. An axicon was then used to create a blend transition zone from 6.5 mm up to 9.4 mm in diameter. Eyes were evaluated at one, three and six months after surgery. Results. Reepithelization was always observed by the fifth postoperative day, despite the large area of deepithelization (diameter 9.5 mm). Mean refractive error one month after treatment was −2.44 ± 1.59 D (range 0.00 to −6.50 D). Five eyes (29.4%) had a best corrected visual acuity loss more than two to three lines; all eyes showed mild annular haze not involving the central part of the cornea. Six months after treatment, mean refractive error was −0.88 ± 0.99 D (range +0.50 to −3.00 D). Compared to preoperative status, 13 eyes (76.5%) showed an improvement in uncorrected distance visual acuity (1–8 lines), and 14 eyes (82.4%) showed an improvement in uncorrected vision at reading distance (3–7 lines). Two eyes (11.7%) showed a best corrected visual acuity loss of two of three lines. Conclusions. These preliminary results indicate this approach is effective in reducing hyperopia, while its predictability has still to be proved in a larger treatment group with longer follow-up. A cautious approach to this technique is still advisable, especially for higher hyperopic corrections, in view of the large best corrected visual acuity loss seen in two eyes at six months.

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Effect of citicoline on visual acuity in amblyopia: preliminary results

Graefe s Archive for Clinical and Experimental Ophthalmology ◽

10.1007/bf00177654 ◽

1995 ◽

Vol 233 (5) ◽

pp. 307-312 ◽

Cited By ~ 44

Author(s):

E. C. Campos ◽

C. Schiavi ◽

P. Benedetti ◽

R. Bolzani ◽

V. Porciatti

Keyword(s):

Visual Acuity ◽

Preliminary Results

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Preliminary Results of Femtosecond Laser Assisted Corneal Ring Segment Implantation for Keratoconus

International Journal of Keratoconus and Ectatic Corneal Diseases ◽

10.5005/jp-journals-10025-1049 ◽

2013 ◽

Vol 2 (2) ◽

pp. 47-50

Author(s):

Vardhaman P Kankariya ◽

Kemal Ozulken ◽

Florence Cabot ◽

Sonia H Yoo

Keyword(s):

Visual Acuity ◽

Femtosecond Laser ◽

Safe Procedure ◽

K Value ◽

Preliminary Results ◽

Corrected Visual Acuity ◽

Uncorrected Visual Acuity ◽

Ring Segment ◽

Preliminary Study

ABSTRACT Purpose To present refractive, visual and topographic outcomes of femtosecond laser assisted intrastromal ring segments (ISRS) implantation. Settings Bascom Palmer Eye Institute, Miami, FL, USA. Materials and methods Nineteen eyes of 15 patients with keratoconus, clear central corneas, and contact lens intolerance had implantation of a symmetrical 0.45 mm Inta cs segment (Addition Technology Inc, California, USA) using 200 kHz femtosecond laser (WaveLight GmbH, Erlangen, Germany). The outcomes of the procedure were evaluated in terms of uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BSCVA), average keratometry value (K-value) and spheric equivalent (SE). Results Femtosecond laser assisted ISRS implantation could be performed with ease, while no intra- or postoperative complications were encountered. Mean UCVA improved from 0.95 ± 0.39 to 0.66 ± 0.28 logMAR, mean BSCVA improved from 0.46 ± 0.13 to 0.29 ± 0.21 logMAR, mean spherical equivalent considerably reduced from −7.15 ± 4.57 to −4.38 ± 4.07 and K value reduced from 52.39 ± 5.79 to 49.78 ± 6.84 D at the last follow-up. Conclusion Using a 200 kHz femtosecond laser is a safe procedure providing optimal refractive, visual and topographic outcomes in our preliminary study. How to cite this article Ozulken K, Cabot F, Kankariya VP, Yoo SH. Preliminary Results of Femtosecond Laser Assisted Corneal Ring Segment Implantation for Keratoconus. Int J Kerat Ect Cor Dis 2013;2(2):47-50.

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The O–C diagrams of minor planets − a new approach to modelling the rotation

International Astronomical Union Colloquium ◽

10.1017/s0252921100031407 ◽

1999 ◽

Vol 173 ◽

pp. 185-188

Author(s):

Gy. Szabó ◽

K. Sárneczky ◽

L.L. Kiss

Keyword(s):

Error Analysis ◽

Time Dependence ◽

Theoretical Work ◽

Minor Planet ◽

Minor Planets ◽

New Approach ◽

Preliminary Results ◽

Ccd Observations

AbstractA widely used tool in studying quasi-monoperiodic processes is the O–C diagram. This paper deals with the application of this diagram in minor planet studies. The main difference between our approach and the classical O–C diagram is that we transform the epoch (=time) dependence into the geocentric longitude domain. We outline a rotation modelling using this modified O–C and illustrate the abilities with detailed error analysis. The primary assumption, that the monotonity and the shape of this diagram is (almost) independent of the geometry of the asteroids is discussed and tested. The monotonity enables an unambiguous distinction between the prograde and retrograde rotation, thus the four-fold (or in some cases the two-fold) ambiguities can be avoided. This turned out to be the main advantage of the O–C examination. As an extension to the theoretical work, we present some preliminary results on 1727 Mette based on new CCD observations.

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Cyclic Evolution of Sunspots: Gleaning New Results from Old Data

International Astronomical Union Colloquium ◽

10.1017/s0252921100064411 ◽

2000 ◽

Vol 179 ◽

pp. 163-165

Author(s):

S. K. Solanki ◽

M. Fligge ◽

P. Pulkkinen ◽

P. Hoyng

Keyword(s):

Sunspot Number ◽

Sunspot Cycle ◽

Preliminary Results ◽

Butterfly Diagram

AbstractThe records of sunspot number, sunspot areas and sunspot locations gathered over the centuries by various observatories are reanalysed with the aim of finding as yet undiscovered connections between the different parameters of the sunspot cycle and the butterfly diagram. Preliminary results of such interrelationships are presented.

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Systematic effects in observed parallaxes

International Astronomical Union Colloquium ◽

10.1017/s0252921100073887 ◽

1978 ◽

Vol 48 ◽

pp. 31-35

Author(s):

R. B. Hanson

Keyword(s):

Error Estimates ◽

Zero Point ◽

Absolute Zero ◽

Apparent Magnitude ◽

Coherent System ◽

Preliminary Results ◽

General Catalogue ◽

Systematic Effects ◽

New Evidence ◽

Right Ascension

Several outstanding problems affecting the existing parallaxes should be resolved to form a coherent system for the new General Catalogue proposed by van Altena, as well as to improve luminosity calibrations and other parallax applications. Lutz has reviewed several of these problems, such as: (A) systematic differences between observatories, (B) external error estimates, (C) the absolute zero point, and (D) systematic observational effects (in right ascension, declination, apparent magnitude, etc.). Here we explore the use of cluster and spectroscopic parallaxes, and the distributions of observed parallaxes, to bring new evidence to bear on these classic problems. Several preliminary results have been obtained.

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Quantitative Measurements on the Ion Etching of TMV

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100072125 ◽

1973 ◽

Vol 31 ◽

pp. 336-337

Author(s):

Irwin Bendet ◽

Nabil Rizk

Keyword(s):

Electron Microscope ◽

Tobacco Mosaic Virus ◽

Mosaic Virus ◽

Ion Current ◽

Beam Diameter ◽

Ion Etching ◽

Preliminary Results ◽

Quantitative Measurements ◽

Monitoring Devices

Preliminary results reported last year on the ion etching of tobacco mosaic virus indicated that the diameter of the virus decreased more rapidly at 10KV than at 5KV, perhaps reaching a constant value before disappearing completely.In order to follow the effects of ion etching on TMV more quantitatively we have designed and built a second apparatus (Fig. 1), which incorporates monitoring devices for measuring ion current and vacuum as well as accelerating voltage. In addition, the beam diameter has been increased to approximately 1 cm., so that ten electron microscope grids can be exposed to the beam simultaneously.

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Granular bainite or granular ferrite? A preliminary TEM investigation of an HSLA-100 steel

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100087239 ◽

1991 ◽

Vol 49 ◽

pp. 584-585

Author(s):

R. Varughese ◽

S. W. Thompson ◽

P. R. Howell

Keyword(s):

Room Temperature ◽

Transformation Products ◽

Accurate Description ◽

Granular Bainite ◽

Preliminary Results ◽

The Past ◽

Light Micrograph ◽

Multiphase Reaction ◽

Detailed Nature

Ever since Habraken and Economopoulos first employed the term granular bainite to classify certain unconventional transformation products in continuously cooled steels, the term has been widely accepted and used, despite the lack of a clear consensus as to the detailed nature of the transformation products which constitute granular bainite. This paper presents the preliminary results of a TEM investigation of an 0.04 wt% C, copper-containing steel (designated HSLA-100). It is suggested that the term granular ferrite rather than granular bainite is a more accurate description of this multiphase reaction product.Figure 1 is a light micrograph of a sample which had been air-cooled from 900°C to room temperature. The microstructure is typical of that which has been termed granular bainite in the past and appears to consist of equiaxed ferritic grains together with other minor transformation products. In order to examine these structures in more detail, both continuously cooled and isothermally transformed and quenched materials have been examined with TEM. Granular bainite has been found in virtually all samples.

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