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Background Photorefractive keratectomy (PRK) is an accepted procedure to correct myopia in Germany. The purpose of this study was to evaluate photoastigmatic refractive keratectomy (PARK) for myopic astigmatism. Material and methods PARK using the VISX 20/20 excimer laser was performed in 50 eyes of 36 patients (25 female, 16 male) aged 22 to 68 years (mean 38 +/- 10 years) in the period of 1995 to 1996. Retrospective evaluation was done after dividing the patients into three astigmatic groups between -0.5 diopters (D) and -1.5 D (group I, n = 28), between -1.75 D and -3.0 D (group II, n = 16) und between -3.25 D and -5.5 D (group III, n = 6). The correction of myopic astigmatism was assessed concerning the criteria safety, efficacy, predictability and stability. Mean follow-up was 12 months (8-15 months). Results Seventy-eight % of all eyes achieved an uncorrected visual acuity of > 0.5. Sixty-eight % of the eyes were within +/- 1.0 D of the desired correction. Loss of 2 or more lines of best corrected visual acuity occurred in 6 eyes (12.0%). We observed in group I an astigmatic reduction of 36.0%, in group II of 66.5% and in group III of 68.0%. The surgically induced astigmatism was calculated with 1.29 +/- 1.0 D. Mean axis rotation of the refractive cylinder was 22.12 +/- 23.05 degrees. Conclusions PARK using the VISX 20/20 excimer laser is an acceptable procedure to correct myopic astigmatism. However, the study revealed that astigmatic reduction with a broad beam laser is not yet perfect in terms of efficacy, predictability and safety.

The advent of the excimer laser has brought about the potential for improved vision in many individuals with myopia and astigmatism. However, photoastigmatic refractive keratectomy (PARK) remains a matter of controversy. The purpose of our study was to determine the predictability of VISX 20/20 excimer laser photorefractive keratectomy in the treatment of myopic astigmatism. Patients and methods: Our study comprised 31 eyes of 22 patients with myopic astigmatism. All patients underwent treatment with a VISX 20/20 excimer laser and were followed up for 6 months. Complete 12-month follow-up data were available from 18 eyes. Park was performed in eyes with myopia between −1.5 and −10.0 D and with astigmatism between −0.5 and −5.5 D. Thus, the corresponding spherical equivalent ranged from −1.75 to −10.5 D. Results: Six months postoperatively, 21/31 (62 %) eyes were within ± 1.0 D of the target refraction and 13/31 (42 %) within ± 0.5 D of the target refraction. In 13 of 15 eyes (87 %) with myopia less than −6.0 D, an uncorrected visual acuity of at least 0.8 was noted. In eyes with myopia greater than −6.0 D, 9/16 (56 %) showed an uncorrected visual acuity of at least 0.5. Six months after PARK, an increase of one line on the Snellen Visual Acuity Chart was observed in 8/31 (26 %) and an increase of two lines was noted in eyes 3/31 (10 %). One of 31 eyes (3 %) showed an increase of three lines. A decrease in visual acuity of 1 line on the Snellen Visual Acuity Chart was found in 4/31 (13 %), and in 3/31 eyes (10 %) a decrease of 2–4 lines was noted. Overall, we observed a statistically significant reduction of astigmatism from 1.93 ± 1.43 D to 0.93 ± 0.63 D. Reduction of corneal astigmatism less than −1.25 D was not statistically significant. In eyes with astigmatism ranging from −1.25 to −2.5 D or greater than −2.75 D, a significant reduction of the mean astigmatism was noted. The postoperative regression of astigmatic correction was low. However, an axis shift of more than 15 ° was found in 42 %/35 % of eyes by subjective refraction (miosis/cycloplegia) and in 33 % in corneal topography. No central islands were noted. Conclusion: Photoastigmatic refractive keratectomy (PARK) constitutes a potential means of correcting myopic astigmatism. In eyes with astigmatism greater than −1.0 D a significant reduction of 60 % of the mean astigmatism was noted. However, the considerable proportion of eyes with a postoperative axis shift greater than 15 ° and a decrease in visual acuity of two or more lines indicates that further research is needed on excimer laser surgery to improve the reliability and safety.

Fibrinolytic therapy aimed at early restoration of blood flow appears to be a promising therapeutic approach in haemorrhagic retinopathy. The risk of bleeding complications, a major problem with fibrinolysis, can be reduced by the use of low-dose thrombolytic regimens. In our study, 14 patients with ischaemic central (CRVO) or branch (BRVO) retinal vein occlusion who presented with severe visual loss and recent onset of symptoms were treated with a low dose (50 mg) of recombinant tissue plasminogen activator (rt-PA) and intravenous heparin. In 10 of 14 patients (7 CRVO, 3 BRVO), an increase in visual acuity of one line or more on the logarithmic visual acuity chart was noted and in 8 patients (6 CRVO, 2 BRVO) a reduction of areas of capillary non-perfusion was observed, suggesting that a restoration of retinal capillary blood flow can be achieved if fibrinolysis is initiated in the early phase of haemorrhagic retinopathy. In view of the poor prognosis in the natural course of haemorrhagic retinopathy and the potential haemorrhagic risk in fibrinolysis, the use of low-dose rt-PA appears to constitute an encouraging approach in the management of this disease.

The purpose of this investigation was to evaluate the safety, efficacy, predictability, stability and complications of LASIK for the treatment of hyperopia and hyperopic astigmatism using a scanning spot excimer laser.A total of 64 consecutive LASIK operations (37 patients, mean age 41 years, range 22-68 years) have been evaluated. The Hansatome microkeratome producing a superior hinge (flap diameter 9.5 mm) and a scanning spot excimer laser with an optical zone of 6.0 mm were used. Examinations were performed preoperatively, after 1 day, 7 days, 1 month, 4 and 12 months.One year after the primary procedure only 1 eye lost 2 or more lines of best-corrected visual acuity, 91% were within +/-1 line and 4 eyes gained 2 lines. Of these eyes 50 (86%) reached an uncorrected visual acuity ofor=0.5, 32 (55%)or=0.8, 16 (28%)or=1.0, 24 eyes (41%) needed a refractive correction of +/-0.5 D, 44 eyes (76%) of +/-1.0 D and 55 eyes (95%) of +/-2.0 D. The mean spherical equivalent after 1 year was +0.17+/-0.85 D.LASIK is suitable for the correction of hyperopia (up to a maximum of +5 D) and for hyperopic astigmatism (up to a maximum of -5 D). However, results were better in lower hyperopia (up to +3 D) than in the moderate hyperopia. The refractive results showed overall a good stability during the 12-month study period, but higher regression occurred in a few cases.

The ischemic type of central retinal vein occlusion (CRVO) is associated with a poor visual and ocular prognosis. Although several reports have indicated that hemodilution or thrombolytic therapy may be of benefit, there is still no consensus among ophthalmologists about the management of this disorder. In our study, we retrospectively evaluated the visual outcome after medical treatment in 58 patients with ischemic CRVO and severe visual loss (≤20/50). We separately investigated three different groups, depending on the following criteria: onset of symptoms within 11 days prior to admission and thrombolytic treatment with 50 mg of recombinant tissue plasminogen activator (rtPA) and intravenous heparinization (n = 23) or hemodilution therapy (n = 22) or onset of symptoms >11 days before the initial visit and hemodilution (n = 13). An advancement of 2 or more lines on the logarithmic visual acuity chart was noted in 10 cases (44%) in the rtPA group and in 3 subjects (14%) in the early-phase hemodilution group, whereas only 1 patient in the late-phase hemodilution group showed a comparable improvement. Our findings suggest that treatment with low-dose rtPA or hemodilution aimed at early restoration of blood flow has the potential to improve the visual prognosis in ischemic CRVO. The finding that thrombolysis had a favorable outcome supports the hypothesis that specific subgroups of patients may benefit from this therapeutic approach. Further investigation will be required to definitively prove the effectiveness of fibrinolytic agents.

Purpose: To evaluate the efficacy and safety of intracameral recombinant tissueplasminogen activator (rt-PA) application for fibrinolysis of fibrin formation after cataract surgery in children. Setting: Johann Wolfgang Goethe-University, Department of Ophthalmology; Frankfurt am Main, Germany. Methods: This study comprised 11 eyes of 10 patients aged 3 to 13 years (mean7.2 ± 3.68 [SD]) who developed severe fibrin formation after cataract surgery and IOL implantation despite intensive topical steroid therapy. Under general anesthesia, fibrinolysis was performed with 10 μg of rt-PA 7.18 ± 2.04 days after intraocular surgery. Follow-up included slitlamp examination, tonometry, visual acuity testing, and ophthalmoscopy. Anterior chamber flare measurements could be performed in 6 eyes. Results: Complete resolution of fibrin formations occurred in 90% of the patients. Inthese cases, no recurrent fibrinous reaction or adverse effects were noted. In 2 eyes of the same patient with a history of juvenile rheumatoid arthritis and chronic uveitis, fibrin clot dissolution was incomplete. A recurrent fibrinous formation could be observed after 2 and 4 weeks, respectively. A beginning band kenatopathy excluding the central and limbal cornea, was noted after 6 and 8 weeks, respectively. Conclusion: Intraocular application of rt-PA 'appears to be a safe and efficacious therapeutic approach in the management of severe fibrinous reactions after pediatric cataract surgery.

Cataract patients and healthy subjects have been examined with the Miller-Nadler Glare-Tester to prove if the results of the glare test show any correlation between the glare disability score and the outdoor visual acuity facing sun. The outdoor vision of cataract patients with a high glare disability score was clearly impaired compared with their indoor vision. Healthy eyes with a normal glare disability score did not show any impairment of visual acuity facing sun. The results of the glare disability examination can therefore be used as a reference for the decision of a cataract operation.