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G U Auffarth

Publications and source records attributed to G U Auffarth.

At least 19 recordsLinked to original sources
PubMed2006

Prospective, non-randomised, long term clinical evaluation of a foldable hydrophilic single piece intraocular lens: results of the Centerflex FDA study.

BACKGROUND: Owing to the improvement of modern intraocular lenses (IOLs) in terms of design and material, posterior capsule opacification (PCO) usually takes 2-3 years to develop. Thus, long term clinical evaluation of new implants is important. METHODS: As part of a prospective, non-randomised FDA trial, the Rayner Centerflex, a foldable hydrophilic acrylic, single piece IOL was implanted in one eye of 83 patients (mean age 73.5 (SD 7.0) years). Over 3 years postoperatively, a standardised FDA protocol concerning IOL safety and efficacy was followed including evaluation of spherical equivalent (SE), best corrected distance visual acuity (BCDVA), endothelial cell count (ECC), flare meter values, PCO development, and anterior capsule shrinkage. RESULTS: Postoperatively, mean SE was stable ranging between -0.3D and 0.17D. After 1-2 months, all patients achieved a BCDVA of 20/40 or better. At 3-6 months postoperatively, mean ECC decreased from 2612 (SD 346) cells/mm2 to 2380 (316) cells/mm2. Mean PCO score for the entire optic increased from 0.20 (0.20) months (3-6 months postoperatively) to 0.87 (0.57) resulting in a Nd:YAG rate of 29.41% after 3 years. No anterior capsule shrinkage was found. CONCLUSION: The Centerflex showed excellent functional results, low values for endothelial cell loss and inflammatory signs, and no anterior capsule shrinkage. PCO formation was higher compared to other IOLs, which could be explained by the incomplete sharp edge at the optic-haptic junctions representing an "Achilles' heel" for cell ingrowth.

Acrylic Resins↗
PubMed2006

Intraocular lens power calculation using ray tracing following excimer laser surgery.

PURPOSE: To evaluate intraocular lens (IOL) power calculation using ray tracing in patients presenting with cataract after excimer laser surgery. METHODS: Ten eyes of seven consecutive patients who presented for cataract surgery following excimer laser treatment without any pre-refractive biometry data were enrolled in this prospective clinical study. Preoperatively, IOL power calculation was performed using a ray tracing software called OKULIX. Keratometry data (C-Scan) were imported and axial length (IOLMaster) was entered manually. Accuracy of IOL power calculation was investigated by subtracting attempted and achieved spherical equivalent. RESULTS: Mean spherical equivalent was -3.51+/-2.77 D (range -10.38 to -0.5 D) preoperatively and -1.01+/-1.08 D (range -2.5 to +0.75 D) postoperatively. Mean error was 0.31+/-0.84 D, mean absolute error was 0.74+/-0.46 D, and IOL calculation errors ranged from -1.39 to +1.47 D. A total of 40% of eyes were within +/-0.5 D, 70% within +/-1.0 D, and 100% within +/-1.5 D. Three eyes with corneal radii over 10 mm showed calculation errors exceeding +/-1.0 D. Mean best-corrected visual acuity increased from 20/60 to 20/30 postoperatively. CONCLUSIONS: IOL power calculation after excimer laser surgery can be difficult, especially when pre-refractive keratometry values are not available. In these cases, ray tracing combined with corneal topography measurements provides reliable and satisfactory postoperative results. However, it is advisable to be careful when calculating IOL power for eyes with corneal radii exceeding 10 mm because of slightly higher prediction errors.

Aged↗
PubMed2006

[Quantitative evaluation of acrylic and silicone intraocular lenses with a sharp optic edge design].

BACKGROUND: At the Department of Ophthalmology, Heidelberg, Germany, posterior capsule opacification (PCO) of a silicone and an acrylic intraocular lens (IOL) with a sharp optic edge design was evaluated. PATIENTS AND METHODS: In a prospective study either the AMO ClariFlex silicone IOL or the Sensar AR40e hydrophobic acrylic IOL were implanted in 47 patients following uneventful phacoemulsification. Mean patient age was 76.2+/-7.8 (ClariFlex) and 73.4+/-12.9 years (AR40e), respectively. The mean follow-up time was 19.7+/-5.34 in the ClariFlex and 21.9+/-1.89 months in the AR40e group. PCO development was evaluated postoperatively using the EPCO 2000 analysis software (scale 0-4). Areas of interest were the total IOL optic, the central 3-mm zone as well as the capsulorhexis. RESULTS: In both groups, all patients achieved a BCVA of 20/32 (AR40e) and 20/25 (ClariFlex), respectively. There was a very low incidence of PCO development with a mean EPCO score of 0.07+/-0.2 (ClariFlex and 0.15+/-0.2 (AR40e). Within the 3-mm zone and the capsulorhexis, there was a tendency for even lower EPCO scores in both groups. We calculated a statistically significant difference for the two lens materials for all investigated IOL areas (Wilcoxon's test, p<0.05). CONCLUSION: Both IOLs with a sharp edge design showed good functional results, a stable position in the capsular bag as well as a low incidence of PCO development. However, the silicone IOL showed statistically significantly lower PCO scores.

Acrylic Resins↗
PubMed2006

[Presbyopia correction using intraocular lenses].

Modern cataract surgery has advanced tremendously over the past 20 years. Improved surgical techniques, as well as improved implant materials and designs, have enlarged patient profiles and indications not only for cataract surgery, but also for refractive lens exchange surgery. This has also created much higher patient expectations. The loss of accommodation is a loss of quality of life for presbyopic and especially young pseudophakic patients. Multifocal intraocular lenses (MIOL) have been implanted since 1986, starting with 2-3 zone refractive and diffractive designs. Due to the surgical techniques available at that time, MIOL decentration and surgically induced astigmatism were possible complications. In addition, reduced contrast perception and increased glare were common problems of MIOL because of their optical principles. New developments in this field in recent years such as the folding, multizonal, progressive refractive MIOL and aspheric diffractive MIOL in combination with improved surgical techniques have overcome those initial problems. Therefore, modern MIOL (and in the future also accommodative IOL) can be considered not only for the correction of aphakia but also for refractive purposes.

Humans↗
PubMed2006

[Accuracy of lens power calculation and centration of an aspheric intraocular lens].

BACKGROUND: Aspherical intraocular lenses (IOLs) are presumed to optimize the optical characteristics of IOLs. In order to profit from these characteristics, exact calculation of the IOL power and good centration of the lens are essential. METHODS: In all, 43 eyes of 43 patients with an average age of 70.9+/-8.3 years underwent implantation of a Tecnis IOL (AMO, Ettlingen) after uneventful cataract surgery with topical anesthesia. IOL power calculation was performed using the Holladay, Haigis, and SRK II formulas. Spherical equivalent refraction and centration and position of the implanted IOLs were measured 6 months postoperatively. Centration of the IOL was analyzed using digital slit lamp photographs and an image analysis program. RESULTS: Best corrected visual acuity (BCVA) increased from 0.47+/-0.25 (LogMAR) preoperatively to 0.1+/-0.11 6 months postoperatively (spherical equivalent +0.3+/-0.6 D). The intraindividual difference between target refraction and achieved postoperative refraction was 0.64+/-0.11 D for the Holladay formula, -0.21+/-0.11 D for the Haigis formula, and 0.97+/-0.15 D for the SRK II formula. The mean decentration of the IOL from the center of the corneal limbus was 0.4+/-0.1 mm. CONCLUSIONS: For the aspherical Tecnis IOL very good postoperative functional results are reported, which are supported by an accurate calculation of the IOL power and a good centration of the IOL inside the capsular bag. In this study the Haigis formula showed the lowest difference between target refraction and achieved postoperative refraction.

Aged↗
PubMed2006

[Pharmacological means to prevent secondary cataract].

Secondary cataract or posterior capsule opacification (PCO) is still the most frequent long-term complication of cataract surgery. Tremendous advances have been made, especially during the last 10 to 15 years, in terms of surgical techniques and improvement of implant technology. However, the problem of proliferation and migration of lens epithelial cells (LECs) postoperatively has not yet been solved completely although we know that a sharp optic edge of intraocular lenses (IOL) combined with hydrodissection, complete overlapping of capsulorhexis and IOL-optic as well as capsular bending reduce PCO formation significantly. In the 1980 s, investigators like Hartmann et al. began with the application of pharmacological substances in-vitro in order to successfully prevent LECs from proliferating and migrating. Cytostatic drugs, steroids, non-steroidal antiphlogistics, adhesion inhibitors, heparin, lidocaine, suramin, immunotoxins, photodynamic therapy and osmotic effective solutions were tested. In several studies different drug delivery systems were investigated in order to provide a longer and more effective impact on LECs. However, the in-vivo use has been viewed critically since the selective targeting of LECs was not possible and serious damage to the surrounding tissue had to be considered. Recently, the development of the PerfectCapsule System for vacuum-sealed capsule irrigation allows the selective targeting of LECs inside the capsular bag. This survey gives an update on past, current and future means and trends to reduce or prevent PCO formation pharmacologically.

Anti-Inflammatory Agents↗
PubMed2005

[New methods for the prevention of posterior capsule opacification].

Even though tremendous advances have been made especially during the last 10-15 years in terms of surgical techniques and improvement of implant technology, posterior capsule opacification (PCO) still remains a serious long-term complication. New clinical and laboratory studies (especially of autopsy eyes) have improved our understanding of how IOL design and material influence PCO. Sharp edge optic designs of IOLs of various materials have been shown to significantly reduce secondary cataract. The application of pharmacological substances selectively into the capsular bag is now possible due to the development of the PerfectCapsule System for vacuum-sealed capsule irrigation. Major advances in other areas of biotechnology and immunology including gene therapeutic methods offer totally new approaches for the future in the elimination of lens epithelium cells from the capsular bag. This survey gives an update on current and future means and trends to reduce or prevent PCO formation.

Biocompatible Materials↗
PubMed2004

[Measurement method for the determination of rotation and decentration of intraocular lenses].

PURPOSE: In the past 50 years the IOL has been improved. Nowadays it is possible to exactly calculate the necessary IOL power and correct toric refractive errors. In this study we developed methods for measuring rotation and decentration using the example of a hydrophilic acrylic IOL. METHODS: Following cataract surgery, the first retroilluminated photograph was taken. The position of the IOL was determined with the image analysis program Adobe Photoshop. RESULTS: Measurement of a rotational movement or of a decentration of an IOL can be done accurately and rapidly. Evaluation of the stability of rotation of the hydrophilic acrylic IOL measured here showed an average rotation of the IOL of 5.3+/-1.4 degrees after 6 months compared to the position directly after implantation. CONCLUSION: The measurement methods presented here are easy to use and provide reliable results. Examiners must have basic knowledge of the computer programs used. Also, these methods depend on good quality of the retroilluminated photographs.

Cataract↗
PubMed2003

[Diagnosis and treatment of mycobacterial keratitis following LASIK. Case report and review of the literature].

BACKGROUND: Mycobacterial keratitis is a rare complication following LASIK but can lead to an extremely unfavourable outcome. The diagnosis and treatment is often delayed due to confusion with other entities including diffuse lamellar keratitis and poor clinical outcomes with flap amputation and/or keratoplasty are often the case. PATIENT AND METHODS: We report the results of LASIK in a 51-year-old woman with subsequent early-diagnosed mycobacterial keratitis and compared this case to treatments and outcomes reported in the literature. RESULTS: The patient presented 10 days following LASIK with a white focal infiltrate in the stromal interface. The flap was lifted and cultures from the stromal bed and the reverse of the flap were obtained and the interface irrigated. The patient was treated with topical antibiotics (ciprofloxacin 0.3%, amikacin 2.5%, clarithromycin 40 mg/ml and tobramycin 15 mg/ml) for 8 weeks and at the most recent follow-up she had a visual acuity of 1.25. CONCLUSION: In a large number of published cases in the literature the flap had to be amputated and/or corneal transplants were necessary. Early diagnosis and treatment however, are essential to successfully treat post-LASIK keratitis. Therefore the patients should be followed up carefully in the early postoperative period.

Anti-Bacterial Agents↗
PubMed2002

[Miyake-Apple video analysis of movement patterns of an accommodative intraocular lens implant].

BACKGROUND: The potentially accommodative intraocular lens (IOL) is a new development in IOL design METHODS: We evaluated the new Humanoptics 1CU accommodative IOL in a laboratory study with human post mortem autopsy eyes. Using the Miyake-Apple posterior view video technique, the movement pattern of the IOL was tested and observed from the posterior perspective. RESULTS. A circular bend at the level of the ciliary body applied slight circular force onto the sclera allowing the relaxation of the zonules. The shift of focus was demonstrated by using a reading target. In addition, viscoelastic was injected into the vitreous resulting in the same anterior movement of the IOL optic. CONCLUSIONS: The 1CU Humanoptics accommodative IOL showed potential accommodative behaviour in the laboratory. The accommodative (respectively pseudoaccommodative) effect was based on the anterior shift principle with anterior movement of the IOL-optic in the state of relaxing zonules. Whether this reflects the clinical situation, especially to this extent, must be further evaluated.

Accommodation, Ocular↗
PubMed2002

[Validity of anterior chamber depth measurements for the evaluation of accommodation after implantation of an accommodative Humanoptics 1CU intraocular lens].

BACKGROUND: Changes in the anterior chamber depth (ACD) after pilocarpin application are generally regarded as reflecting an accommodative effect of accommodative intraocular lenses (IOLs) METHODS: We implanted Humanoptics 1CU accommodative IOLs into 25 eyes of 20 patients aged 53.2+/-14.7 years (range: 30-83 years). In seven of these patients, we were able to measure anterior chamber depth changes after the application of pilocarpine (2%) eye drops 3 months postoperatively using a Zeiss IOLMaster, an Orbscan II topography system, as well as by ultrasound biomicroscopy (20 MHz-US-head). RESULTS: Uncorrected near acuity was on average 0.4+/-0.23 (0.1-0.8) and uncorrected distance acuity was 0.76+/-0.23 (0.3-1). Before pilocarpine, ACD was 3.19+/-2.11 mm (IOL-Master), 3.35+/-2.22 mm (Orbscan II) and 3.35+/-2.21 mm (US-biomicroscopy) ( P=0.96). After pilocarpine, ACD was 2.61+/-1.71 mm (IOL-Master), 2.63+/-1.78 mm (Orbscan II) and 3.15+/-2.08 mm (US-biomicroscopy) ( P=0.002). The average individual ACD change before/after pilocarpine was 0.83+/-0.25 mm with the IOL-Master, 1.04+/-0.39 mm with the Orbscan II System and 0.28+/-0.14 with US-biomicroscopy ( P=0.0004). DISCUSSION: The 1CU Humanoptics accommodative IOL presented with potential accommodative capabilities in clinical evaluation. Drug induced accommodation by pilocarpine does not reflect real accommodative effects. The differences in ACD measurements between three different methods were statistically significant. Evaluation methods for accommodative IOLs should be carefully analysed and further development of objective means for evaluation is needed.

Accommodation, Ocular↗
PubMed2001

[The life work of Sir Nicholas Harold Lloyd Ridley].

On may 25th 2001 Sir Harold Ridley died at age 94. With him Ophthalmology lost one of the greatest and most influential Ophthalmologist of the post-war time. He is the founder of modern cataract surgery implanting the first intraocular lens after extracapsular cataract extraction 50 years ago. He pioneered in what became one of the most important success stories in Ophthalmology. His vision and concepts managed to succeed against strong opposition worldwide. Modern cataract surgery and modern refractive IOL surgery would not been possible without his contribution. Sir Harold Ridley reached a high age and was therefore able to see his visions become reality and finally receive all honours and awards he deserved over the past 15 years, including the knighthood by Queen Elisabeth II in the year 2000. The following article gives a summary of his biography and contributions to Ophthalmology.

Cataract Extraction↗