Search PubMed⌕ Search

Biomedical subjects

A Liermann

Publications and source records attributed to A Liermann.

12 recordsLinked to original sources
PubMed2001

[Results of implantation of a Worst Iris Claw Lens for correction of high myopia].

BACKGROUND: The purpose of this clinical study was to evaluate refraction, best visual acuity and anterior chamber flare after implantation of a Worst Iris Claw Lens to correct high myopia. PATIENTS AND METHODS: From September 1996 to February 1999 the implantation of a Worst Iris Claw lens was performed on 44 highly myopic phakic eyes of 28 patients. Data after 6 weeks and 6 months follow-up were assessed. RESULTS: The mean preoperative spherical equivalent was--17.35 +/- 3.57 dpt and 6 months after implantation 79% of the eyes were within +/- 1.0 dpt of target refraction. The mean best corrected visual acuity increased from 0.43 preoperatively to 0.65 postoperatively and 6 months after the treatment there was no flare (< 10 photons/ms) in 21% and a mild anterior chamber flare (10-80 photons/ms) in 76% of the treated eyes. The median laser flare was 20 p/ms. CONCLUSIONS: In conclusion, implantation of a Worst Iris Claw lens has proved to be a precise method to correct high myopia. No or mild anterior chamber flare and a good visual acuity were measured in most eyes 6 weeks and 6 months after surgery. Longer follow-up periods are needed to assess the long-term safety and efficiency.

Follow-Up Studies↗
PubMed1999

[Complications of laser in situ keratomileusis (LASIK)].

BACKGROUND: The incidence and course of intraoperative and postoperative complications of LASIK were investigated. PATIENTS AND METHODS: We consecutively treated 598 eyes (316 patients) using the Automatic Corneal Shaper and the Keracor 117 C excimer laser. One hundred and sixty-three eyes were also available at 12 months. The preoperative spherical equivalent was -5.31 +/- 5.49 D (+9 to -23 D). We evaluated intra- and postoperative complications. RESULTS: Intraoperative complications of keratotomy were observed in 1.3% (irregular cut, n = 5; free cap, n = 2; incomplete cap, n = 1), and other intraoperative complications in 1.7% (epithelial defects, n = 7; flap dislocation, n = 1; lateral kanthotomy required, n = 2). None of these complications caused any long-term effects or loss of two or more lines of visual acuity. Postoperative complications were observed in 0.9% (peripheral epithelial ingrowth, n = 4; keratectasia, n = 1; subretinal neovascularisation, n = 1). CONCLUSIONS: The rate of complications in LASIK is low, and intraoperative complications did not cause any significant loss of vision. We observed keratectasia in one eye, which suggests that deep ablations should be avoided, which limits the amount of correction possible.

Adolescent↗
PubMed1999

[Twilight visual acuity after correction of myopia with LASIK].

BACKGROUND: Data on mesopic vision after LASIK are not available to date. We therefore evaluated mesopic vision in myopic eyes before and after LASIK. PATIENTS AND METHODS: Sixty-seven eyes (34 patients) treated using the Automatic Corneal Shaper and the Keracor 117CT spot-scanning excimer laser were included. All eyes had best-corrected vision of 20/25 or better preoperatively. We measured spectacle refraction, visual acuity, and mesopic vision without and with glare (Nyktometer, Rodenstock) both preoperatively and 1 year after LASIK. Results were evaluated in three groups with reference to baseline refraction, and numbers of patients who saw a contrast of 1:5 or less were compared. RESULTS: Myopia -1 to -5 D (group 1; n = 26): Preoperatively (postoperatively), 89% (96%) (P = 0.03) of eyes identified a contrast of 1:5 or less without glare, while 65% (73%) achieved that level with glare. Myopia -5.1 to -10 D (group 2; n = 24): Preoperatively (postoperatively), 83% (75%) of eyes identified a contrast of 1:5 or less without glare, while 50% (21%) achieved that level with glare. Myopia -10.1 to -15 D (group 3; n = 11): Preoperatively (postoperatively), 73% (55%) of eyes identified a contrast of 1:5 or less without glare, while 46% (27%) achieved that level with glare. CONCLUSIONS: LASIK seems to cause a reduction of mesopic vision under glare conditions in corrections of more than -5 D. In corrections of more than -10 D, mesopic vision without glare is reduced, too. However, differences were not statistically significant when comparing vision at contrasts of 1:5 and lower. In addition, mesopic is considerably reduced in high myopes even preoperatively.

Adult↗
PubMed1998

[LASIK for myopia correction. 2-year follow-up].

BACKGROUND: Long-term results on LASIK are not available to date. We therefore evaluated the predictability, stability and complication rate after LASIK in moderate--to-high myopia. PATIENTS AND METHODS: We treated 70 eyes (41 patients) using the Automatic Corneal Shaper and the Keracor 116 excimer laser. Patients were followed for 1, 6, 12 and 24 months. Spectacle refraction, visual acuity, rate of retreatment, and patient satisfaction were evaluated. RESULTS: At 24 months the results were as follows: Myopia -5 to -9.9 D (n = 18): 94% within 1 D; regression between 1 and 12 (12 and 24) months > 1 D in 6% (6%); uncorrected acuity 20/40 or better in 83%; no loss of 2 ore more lines of visual acuity; 89% highly satisfied. Myopia -10 to -14.9 D (n = 12): 88% within 1 D; regression between 1 and 12 (12 and 24) months > 1 D in 20% (0%); uncorrected acuity 20/40 or better in 72%; 4% lost 2 or more lines of visual acuity; 96% highly satisfied. Myopia -15 to -29 D (n = 22): 33% within 1 D; regression between 1 and 12 (12 and 24) months > 1 D in 41% (18%); uncorrected acuity 20/40 or better in 7%; no loss of 2 or more lines of visual acuity; 67% highly satisfied. CONCLUSION: LASIK is an accurate, effective and stable procedure for correcting myopia of -5 to -10 D. Results are less precise in myopia up to -15 D, and some visual loss occurs in a number of patients. In myopia > -15 D, results are not satisfactory because of poor accuracy and low stability.

Adult↗
PubMed1998

Laser in situ keratomileusis for moderate and high myopia and myopic astigmatism.

OBJECTIVE: This study evaluated the predictability, stability, and safety of laser in situ keratomileusis (LASIK) in myopia and myopic astigmatism. DESIGN: The study design was a prospective, unmasked, nonrandomized clinical trial. PARTICIPANTS: Participating were 25 patients with myopia (37 eyes) with astigmatism of less than 1.00 diopter (D), divided into 3 subgroups (-5.00 to -9.90 D, 8 eyes; -10.00 to -14.90 D, 10 eyes; -15.00 to -29.00 D, 19 eyes), and 37 patients with myopia (56 eyes) with corneal astigmatism of 1.00 to 4.50 D, divided into 3 subgroups (-5.00 to -9.90 D, 12 eyes; -10.00 to -14.90 D, 24 eyes; -15.00 to -29.00 D, 20 eyes). INTERVENTION: LASIK was performed using the Automatic Corneal Shaper and the Keracor 116 excimer laser. MAIN OUTCOME MEASURES: Visual acuity, manifest refraction, central corneal islands, ablation decentration, and patient satisfaction were measured. RESULTS: At 12 months, predictability, regression between 1 and 12 months, uncorrected visual acuity (UCVA), loss of two or more lines of corrected visual acuity, and patient satisfaction of the spherical (toric) groups are reported. Subgroups -5.00 to -9.90 D: 100% (75%) +1.00 D; regression less than or equal to 1.00 D in 100% (91.7%); UCVA greater than or equal to 20/40 in 87.5% (70%); none lost two or more lines; 100% (84%) highly satisfied. Subgroups -10.00 to -14.90 D: 60% (78.3%) +/-1.00 D; regression less than or equal to 1.00 D in 100% (87%); UCVA greater than or equal to 20/40 in 77.8% (86.4%); 10% (4.3%) lost two lines; 90% (91%) highly satisfied. Subgroups -15.00 to -29.00 D: 38.9% (21.4%) +/-1.00 D; regression less than or equal to 1.00 D in 72.2% (64.3%); UCVA greater than or equal to 20/40 in 33.3% (40%); 5.6% (7.1%) lost two lines; 78% (50%) highly satisfied. Differences of predictability and change of manifest refraction between subgroups of -5.00 to -9.90 D and -15.00 to -29.00 D were statistically significant. Central islands (decentrations) were observed in 17% (5.6%) of eyes of the spherical and in 16% (4.1%) of the toric group. Overall, the corneal interface was visible in 8.2%. CONCLUSIONS: The LASIK method used in this study showed stability of manifest refraction and adequate uncorrected central visual acuity in a large percentage of patients with myopia up to -15.00 D. Corneal stability was not as uniform. Central corneal islands were observed in a sizable minority of patients despite pretreatment. For myopia greater than 15.00 D, accuracy and patient satisfaction were sufficiently poor to advise against using the authors' treatment technique in these groups. Visually significant microkeratome and laser-related problems were noted in a smaller percentage of patients. Patients with astigmatism correction were less pleased with results than were patients who received spherical corrections.

Adolescent↗
PubMed1998

Laser in situ keratomileusis assisted by corneal topography.

PURPOSE: To assess whether laser in situ keratomileusis (LASIK) assisted by corneal topography can successfully treat corneal irregularities or irregular astigmatism in patients with previous ocular surgery or ocular trauma. SETTING: University Eye Hospital, Klinikum Mannheim, Mannheim, Germany. METHODS: In a prospective clinical study, LASIK was performed in 23 eyes of 22 patients. Reasons for surgery were irregular astigmatism after penetrating keratoplasty or penetrating injury or corneal irregularity after previous excimer laser surgery. Excimer ablation was based on preoperative corneal topography data (Corneal Analysis System, EyeSys Technologies) using a proprietary algorithm (Topographic Assist LASIK, Chiron Vision). Follow-up was 6 months. RESULTS: Mean preoperative uncorrected visual acuity (UCVA) was 20/80 and mean best spectacle-corrected visual acuity (BSCVA), 20/35. Uncorrected visual acuity improved in all but two cases. Postoperatively, mean UCVA increased to 20/50; mean BSCVA was unchanged. No eye lost two or more lines of BSCVA. Postoperative topography showed less corneal irregularity in 81.3% of eyes; full correction was achieved in 19.4%. Four eyes (19.4%) needed re-treatment for undercorrection and three eyes (14.3%) for regression. CONCLUSION: Preliminary results indicate that the concept of topographic-assisted LASIK is feasible. However, most eyes were undercorrected and had regression. One reason might be that corneal topography underestimated corneal irregularity, causing significant undercorrection.

Adolescent↗
PubMed1997

[Laser in situ keratomileusis (LASIK) for correction of myopia].

BACKGROUND: Laser in situ keratomileusis (LASIK) preserves the corneal epithelium and Bowman's layer, which theoretically minimizes corneal scarring. We, therefore, evaluated the accuracy, stability and safety of LASIK in moderate to high myopia. PATIENTS AND METHODS: Eighty-five eyes (50 patients) treated using the Automatic Corneal Shaper and the Keracor 116 excimer laser were followed up for 1, 6, and 12 months. Spectacle refraction, visual acuity and rate of retreatments were evaluated. RESULTS: At 12 months, results were as follows: Myopia -5 to -9.9 D (n = 20); 85% within 1 D; regression between one and 12 months < or = 1 D in 90%; uncorrected acuity 20/40 or better in 75%; no loss of two or more lines of visual acuity. Myopia -10 to -14.9 D (n = 33): 73% within 1 D; regression between 1 and 12 months < or = 1 D in 91%; uncorrected acuity 20/40 or better in 79%; 6.1% lost two lines of visual acuity. Myopia -15 to -29 D (n = 32): 31% within 1 D; regression between one and 12 months < or = 1 D in 63%; 6.3% lost two or more lines of visual acuity. Reoperations were performed in two eyes (2.4%) due to epithelial ingrowth or folds of the flap, and in four eyes (4.7%) because of undercorrections or "central islands". CONCLUSIONS: LASIK is an accurate and stable procedure for correcting myopia of -5 to -15 D. In higher myopia, however, results are not satisfactory.

Adult↗
PubMed1996

[Correction of myopia using laser in situ keratomileusis (LASIK)].

BACKGROUND: In contrast to photorefractive keratectomy (PRK), the corneal epithelium and Bowman's layer are preserved in LASIK. Thus, there should be less scarring and regression after LASIK than after PRK. PATIENTS: Between December 1993 and October 1995, we treated 113 eyes (66 patients). The Automated Corneal Shaper and the Keracor 116 excimer laser were used. We evaluated refraction, visual acuity and corneal topography. RESULTS: To date, 61 eyes reached six months follow up. Mean preoperative refraction was -14.3 D (-3.3 to -29 D; SD = 7). Mean deviation from target refraction was -1.4 D (-9.5 to +2.5 D; SD = 2.7) at six months. 34% were within +/-0.5 D of target refraction, 46% within +/-1 D, 67% within +/-2 D, and 82% within +/-3 D. Mean change of refraction ("regression") from one to six months postoperatively was +0.13 D (-7.5 to +8 D; SD = 2.1). Refractive change was < 0.5 D in 51%, < 1 D in 66%, < 2 D in 84%, and < 3 D in 89%. In 88% of eyes, the corneal interface was not or just barely visible, while it was clearly visible in 12%. No scars were observed. CONCLUSIONS: Our results indicate that LASIK is an effective procedure in the correction of high myopia. The incidence of scar formation and regression is considerably lower than after PRK.

Adolescent↗
PubMed1992

[Resorbable pericardial replacement--an experimental study].

The resorbable pericardial substitute: In modern heart surgery every patient undergoing cardiac surgery will eventually require a second operation including resternotomy. To reduce the risk of damage to the heart it has been recommended to close the pericardial sac primarily. Unfortunately there is no ideal pericardial substitute yet available. This experimental study summarizes our experience with the use of Gore-Tex Surgical Membrane and Vicryl-Collagen mesh as pericardial substitutes which have been implanted orthotopically in 12 rats. After a mean follow-up of 86 days we evaluated macroscopically the pericardial adhesions, the closure of the pericardial defect and histologically the inflammatory reaction. At explanation we found that both pericardial substitutes produce little adhesion. But in rats with Vicryl-Collagen mesh as a pericardial substitute there were only a very few inflammatory cells and total closure of the pericardial defect was in 4 out of 6 rats present. These findings suggest that Vicryl-Collagen mesh seems to be a superior pericardial substitute and also allows formation of a neopericardium.

Animals↗
PubMedDate not supplied

Laser in situ keratomileusis to correct myopia of -6.00 to -29.00 diopters.

BACKGROUND: Photorefractive keratectomy can cause corneal scarring and visual loss in highly myopic eyes. We evaluated laser in situ keratomileusis (LASIK) because it has the theoretical advantage of preserving both the corneal epithelium and Bowman's layer. METHODS: In a prospective study, LASIK was performed in 62 myopic eyes (42 patients) using the Automatic Corneal Shaper (Chiron Vision) and the Keracor 116 excimer laser (Chiron Technolas). We measured refraction and visual acuity, and evaluated corneal topography (TMS 1) and corneal clarity after 4 to 8 weeks and 4 to 6 months. RESULTS: Four- to 6-month follow up was completed in 51 eyes. The mean preoperative spherical equivalent refraction was -14.80 diopters (D) (range, -6.00 to -29.00 D). Postoperatively, the mean deviation from the target refraction was -1.70 D (range, -9.00 to +2.50 D) at 4 to 8 weeks and -1.90 D (range, -9.50 to +2.25 D) at 4 to 6 months. At 4 to 6 months, 19 eyes (37%) were within +/- 0.50 D of the target refraction, 24 (47%) within +/- 1.00 D, 33 (65%) within +/- 2.00 D, and 40 (78%) within +/- 3.00 D. From 4 to 8 weeks to 4 to 6 months, the mean regression of myopia was -0.20 D (0.50 D or less in 24 eyes [47%], 1.00 D or less in 32 [63%], and 2.00 D or less in 42 [82%]). In six eyes (12%), the stromal interface was not visible, in 38 (74%) it was barely visible, and in seven (14%) it was clearly visible. Corneal topography revealed only small variations in clear-zone size and dioptric value, demonstrating a very stable correction 4 to 6 months postoperatively. CONCLUSIONS: LASIK may be a safe and effective procedure to correct high myopia. Further research is required to develop satisfactory microkeratome technology, effective laser algorithms, and to determine long-term stability of refraction.

Adolescent↗