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G U Auffarth

Publications and source records attributed to G U Auffarth.

69 records · Page 4Linked to original sources
PubMed1995

[No-stitch tunnel incision vs. corneoscleral incision. A prospective, randomized study].

An important factor in early visual recovery after cataract surgery is surgically induced astigmatism. In a randomized clinical trial we compared the development of astigmatism and visual acuity after three different types of incision and suture techniques. Sixty-seven patients were randomized into three groups: (a) scleral tunnel incision (5 mm) without suture (no stitch) (n = 23) (b) scleral tunnel incision (5 mm) with suture (single stitch) (n = 23) (c) corneoscleral incision (5 mm) with suture (CS suture) (n = 21). Implants: 5 mm optic size; follow-up period: 6 months. There was no statistically significant difference among the 3 groups concerning age distribution and preoperative astigmatism. Postoperative follow-up at day 1, weeks 1, 2, months 1, 4 and 6 showed astigmatic values ranging from 0.84 to 1.41 D (means values, vector analysis; differences not significant: P > 0.10). The surgically induced astigmatism ranged from 1.13-1.74 D (differences not significant P > 0.16). At all follow-up dates the mean uncorrected distance acuity did not differ significantly among the three groups (P > 0.35). No quantitative statistically significant differences could be detected among the three incision and suture techniques.

Aged↗
PubMed1995

[Centering the posterior chamber lens in autopsy eyes with and without pseudoexfoliation syndrome].

The pseudoexfoliation syndrome (PEX) is an important risk factor for cataract surgery. In this study we examined a series of 24 autopsy eyes with PEX that had undergone cataract surgery and intraocular lens (IOL) implantation. The eyes were grossed for IOL fixation and centration. The results were compared to a control group of 25 non-PEX autopsy eyes that matched the PEX series in age distribution, implant duration and anatomical parameters (i.e., axial length) (P > 0.18). The mean IOL decentration in all PEX eyes (0.75 +/- 0.38 mm) was significantly higher than in the control group (0.40 +/- 0.29 mm) (P = 0.0008). Analysis of subgroups with symmetrical bag/bag fixated IOLs also showed significant higher decentration in the PEX group (P = 0.04). The main reason for decentration was decentration of the entire capsular bag in the PEX eyes (0.28 +/- 0.19 vs 0.10 +/- 0.16 in controls; P = 0.001). Patients with PEX showed a higher amount of IOL decentration. The results indicate that the insufficient suspension apparatus of the lens and decentration of the entire capsular bag are the main reasons for IOL decentration in patients with PEX.

Aged↗
PubMed1994

Are there acceptable anterior chamber intraocular lenses for clinical use in the 1990s? An analysis of 4104 explanted anterior chamber intraocular lenses.

PURPOSE: The authors pose the question as to whether there are any anterior chamber intraocular lenses (AC IOLs) acceptable for clinical use in the 1990s. METHODS: Data on the incidence and types of complications of 4104 AC IOLs that were submitted to the Center for IOL Research from 1982 to 1993 were retrieved from the laboratory database and analyzed using cumulative frequency calculations and the chi-square test. Normalized explantation rates were related to implantation rates that were derived from market-share analysis. RESULTS: Of 4104 explanted IOLs, 50% were closed-loop designs (n = 2095/4104); 26% (1100/4104) were miscellaneous, older designs; and 22% (919/4104) were open-loop lenses. The most important complications were corneal pathology (2065/4104) and inflammation (1370/4104). Closed-loop designs were responsible for almost 80% of corneal pathology, with an increasing complication rate with ongoing implant duration (P < 0.0001). Open-loop AC IOLs showed, in relation to their normalized rate of implantation, a significantly lower rate of complications and explantations (P < 0.01). CONCLUSION: Complication rates of flexible, open-loop AC IOLs are much lower than previously assumed. They should be distinguished clearly from most older AC IOL designs. Consideration of these lenses as an alternative to sutured posterior chamber IOLs for secondary or exchange implantation may be warranted for selected clinical indications. They also could provide an alternative to the aphakic spectacle rehabilitation program in developing countries, which will have a positive impact on the overwhelming backlog of patients with cataract in the underprivileged world.

Anterior Chamber↗
PubMed1994

Capsulorhexis in the rabbit eye as a model for pediatric capsulectomy.

Continuous curvilinear capsulorhexis (CCC) is now a standard procedure in cataract surgery. In pediatric eyes, however, this technique is difficult to perform. Because of the elasticity and tension of the pediatric anterior lens capsule, the danger of radial tears is high. Similar conditions are found in the rabbit eye. The anterior lens capsule of young albino rabbits is very elastic. We developed a CCC technique in rabbits that allows a controlled round capsular opening. This technique was used in an experimental study with 16 rabbits (32 eyes). Mean capsulorhexis diameter was 4.9 mm +/- 0.9. A radial tear occurred in only two of 32 cases. The technique, which permits a controlled circular anterior capsulectomy for capsules with high surface tension and elastic properties, may be useful in pediatric cases. A clinical trial appears warranted.

Animals↗
PubMed1994

Neodymium:YAG laser damage on silicone intraocular lenses. A comparison of lesions on explanted lenses and experimentally produced lesions.

In this study we examined 17 explanted silicone intraocular lenses (IOLs) (two one-piece, 15 three-piece) that had evidence of neodymium:YAG (Nd:YAG) laser damage. The majority of lenses (47.1%) had been explanted because of persistent pigment deposits and chronic inflammation. Decentration or IOL dislocation had occurred with 29.4% of lenses. All 17 patients had had Nd:YAG laser posterior capsulectomy, anterior surface polishing, or both; treatments ranged from one to 13 times. By both clinical and gross examination, the laser lesions appeared dark. This was misinterpreted by some opthalmologists as pigment deposits and some patients had additional Nd:YAG laser treatment, which increased the severity of the laser damage. The mean depth of laser damage on the IOLs was 143 +/- 113.4 microns. It was between 51 and 175 microns in approximately 61.0% and deeper than 300 microns (maximum 660 microns) in 9.3%. We compared the explanted IOLs with silicone IOLs that were experimentally damaged using standard power levels from 0.3 to 3.0 mJ and different focal areas. The appearance of the experimentally induced laser burns was equivalent to that on the explanted IOLs, especially the dark laser pits. Since the laser lesions may resemble pigment deposits on slitlamp examination, we recommend careful examination of patients prior to planned laser therapy.

Cataract Extraction↗
PubMed1994

[Area of contact of the artificial lens and posterior capsule. Systematic study of various haptic parameters].

New techniques in cataract surgery, namely the small and tunnel incisions, have led to intraocular lens (IOL) designs with haptics angulated anteriorly as low as 0 degrees. Clinical and animal studies strongly support the inhibitory influence of contact between the optic and the posterior capsule on the formation of posterior capsular opacification. Human cadaver eyes were used to examine the effect of different haptic angulations (1 degree, 5 degrees, 10 degrees, 15 degrees), different haptic diameters (11.5 mm, 12.0 mm, 12.5 mm), and different optic diameters (5.0 mm, 6.0 mm) on the area of contact between optic and posterior capsule. Exciting fluorescein with a Wood light visualized the space between the IOL and the posterior capsule. Only IOLs with haptics bent forward at more than 10 degrees could achieve contact between IOL and posterior capsule. The haptic and optic diameters had only a limited effect.

Humans↗
PubMed1994

[Night driving capacity of pseudophakic patients].

One hundred pseudophakic patients (aged 62.1 +/- 10.8 years) were examined for glare sensitivity and contrast vision, using the Mesoptometer II, 15.8 +/- 9.8 months after implantation of monofocal intraocular lenses. The patients were tested in order to determine whether they met the requirements of the German Ophthalmological Society (DOG) for the granting of a driver's license. The patients were divided into three groups: (1) pseudophakic bilaterally (n = 50), (2) pseudophakic in one eye with phakic contralateral eye (n = 25), and (3) pseudophakic in one eye with cataract in contralateral eye (n = 25). There were no differences between the groups in corrected distance acuity (ANOVA, P = 0.17). Fifty-two percent of the patients did not fulfill the requirements of the DOG (group 1 50%, group 2 24%, group 3 84%). In groups 1 and 2 the binocular results for glare sensitivity and contrast vision were significantly better than the monocular results (P < 0.001). In group 3, however, there was no difference between binocular and monocular results (P > 0.3). In 20% of patients in this group the binocular results were worse than the monocular results. Results for both contrast vision and glare sensitivity were significantly related to age. Overall, this population of pseudophakic patients were 40-50% less suited to night driving than were healthy volunteers with normal eyes.

Aged↗
PubMed1994

[Reasons for the explantation of posterior chamber lenses].

In this study we analysed the overall incidence and the types of complications seen after cataract surgery and implantation of posterior chamber intraocular lenses (PC-IOLs) based on a review of 1460 explanted PC-IOLs. Of these explanted PC-IOLs, 1072 (73.4%) were three-piece PMMA IOLs with Prolene haptics, 261 (17.9%) were one-piece all-PMMA IOLs, 81 (5.6%) were silicone IOLs and 46 (3.1%) were of various other designs (multifocal IOLs, disc IOLs etc.). The mean implant duration for all IOLs was 25.57 +/- 29.24 months. The two most important reasons for explantation were IOL decentration (622/1460, 42.6%) and inflammation (347/1460, 23.77%). There was no difference in reasons for explantation between one-piece and three-piece IOLs. Operative techniques such as "can opener" capsulotomy and sulcus fixation have more influence on IOL decentration than the IOL design alone. Modern operative techniques such as continuous curvilinear capsulorhexis, phacoemulsification and symmetrical in-the-bag fixation of "capsular IOLs" should decrease the explantation and complication rate in the future.

Follow-Up Studies↗
PubMed1994

[Complications after implantation of anterior chamber lenses. An analysis of 4,100 explanted intraocular lenses].

In this study we analyzed the incidence and types of complications seen after cataract surgery and implantation of anterior chamber intraocular lenses (AS-IOLs). This report is based on a review of 4104 explanted AC-IOLs that were submitted to the Center for IOL Research over the past 10 years. The results from pathological examinations were correlated with clinical information. Of the 4104 IOLs, 50% were closed-loop designs (n = 2095/4104), and 22% were open-loop lenses (919/4104). The IOLs most frequently explanted were the closed loop designs Leiske (n = 847) and Stableflex (n = 808). The most important reason for explantation was corneal pathology. Closed-loop IOLs had a much higher complication rate than open-loop lenses. Flexible open-loop AC-IOLs showed the highest explantation rate during the first postoperative year due to surgical problems. The complication rate of closed-loop AC-IOLs increased with implant duration and were responsible for 80% of the corneal pathology. Flexible open-loop AC-IOLs can be an alternative for secondary or exchange implantation. Furthermore, they could also be a viable alternative for cataract surgery in developing countries in order to help catch up with the overwhelming backlog of cases that exist there.

Aged↗
PubMed1994

[Capsulorhexis technique in pediatric cataract. Presented in the rabbit model].

Continuous curvilinear capsulorhexis (CCC) has become a standard procedure in cataract surgery. In pediatric cataracts, however, this technique is difficult to perform. Because of the elasticity and tension of the pediatric anterior lens capsule the danger of radial tears is high. Similar conditions are found in the rabbit model. The anterior lens capsule of young albino rabbits is very elastic. We have developed a CCC technique in rabbits that allows a controlled round capsular opening. This technique was used in an experimental study with 16 rabbits (32 eyes). The mean capsulorhexis diameter was 4.9 +/- 0.9 mm. A radial tear occurred in only 2/32 cases. The technique permits a controlled circular anterior capsulectomy for capsules with high surface tension and elastic properties. This can readily be applied to human pediatric cases.

Animals↗
PubMed1993

Depth of focus and functional results in patients with multifocal intraocular lenses: a long-term follow-up.

We did a follow-up study of 35 patients who had phacoemulsification with implantation of diffractive, multifocal intraocular lenses (IOLs) 2.5 years ago. The patients had an average age of 58.2 +/- 9.6 years. Fifty multifocal IOLs were implanted (3M 815LE, n = 45; 3M 825X, n = 5). Refractive values, visual acuity, depth of focus, and the dependence on corrective glasses were evaluated. Eighty percent of the spherical equivalents ranged from -1 to +1 D (mean 0.25 +/- 0.71). In 76% the cylindric power was not higher than 1 D (mean 0.87 +/- 0.64). With distance correction, 100% of the patients achieved a visual acuity of 20/40 or better. Without correction, 86% achieved 20/40 or better. Near acuity of 20/40 or better with only distance correction was achieved in 98% of patients. Ninety-four percent had a near acuity of 20/40 or better without any correction. The depth of focus was significantly better in the multifocal group than in a control group of patients with monofocal IOLs (P < .01). Although 90% of the patients had good uncorrected visual acuity results of 20/40 or better for near and distance, 58% preferred glasses for distance and/or near.

Accommodation, Ocular↗
PubMed1993

[Long-term results of contrast perception and glare sensitivity in patients with diffraction multifocal lenses].

OBJECTIVE: To test the longterm findings for glare and contrast sensitivity in patients with diffractive multifocal intraocular lenses. STUDY DESIGN: Measurements were done using the Mesoptometer II under standardized contrast level and brightness illumination settings (0.032 and 0.1 cd/m2 brightness illumination for testing contrast sensitivity (0.1 cd/m2 brightness illumination and glare of 0.35 Lux for glare testing). Furthermore the patients were tested on their ability to fulfill the requirements of the German Ophthalmological Society (DOG) for mesopic vision to obtain a driver's license. PATIENTS: 40 patients with multifocal intraocular lenses (MIOL), aged 59.3 +/- 9.1 years, were examined 2 years after lens implantation (3M 815 LE and 3M 825 XE) and compared to results of a control-group of 40 patients with monofocal IOL's. RESULTS: There were no significant differences testing contrast sensitivity. Patients with monofocals, however, reached significant better results than patients with multifocals (p < 0.01) when tested for visual acuity under low contrast conditions and glare sensitivity. CONCLUSIONS: Seventy percent of MIOL-patients and 56% of Monofocal-patients failed to meet the minimum requirements for driver's license. Both patient groups showed decreased values for glare and contrast sensitivity when tested 2 years after cataract surgery.

Adaptation, Ocular↗
PubMedDate not supplied

Intraocular lens implants: a biocompatibility review.

The natural aging process of the eye inevitably leads to the formation of a cataract, resulting in an increasing loss of vision. A cataract is the clouding of the natural lens in the eye and represents a major physical impairment. Modern surgical techniques allow for removal of the clouded lens and replacement with a prosthetic intraocular lens. This article reviews the intraocular tissue response to the implant, which frequently leads to postoperative complications for the patient.

Humans↗