Steinkamp Gw

Fibrinolytic Therapy with Low-Dose Recombinant Tissue Plasminogen Activator in Retinal Vein Occlusion

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.

Visual Outcome after Treatment with Low-Dose Recombinant Tissue Plasminogen Activator or Hemodilution in Ischemic Central Retinal Vein Occlusion

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.

Intraocular recombinant tissue- plasminogen activator fibrinolysis of fibrin formation after cataract surgery in children

PURPOSE To evaluate the efficacy and safety of intracameral recombinant tissue plasminogen 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 (mean 7.2 +/- 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 micrograms 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 in these 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 keratopathy 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.

LASIK mit superiorem Hinge und Scanning-Spot-Excimerlaserablation zur Korrektur von Myopie und myopem Astigmatismus: Einjahresergebnisse einer prospektiven klinischen Studie an 100 Augen

ZusammenfassungHintergrund. In den letzten Jahren wird die Laser-in-situ-Keratomileusis (LASIK) vermehrt zur Korrektur von Fehlsichtigkeiten eingesetzt. Ziel der vorliegenden Auswertung war es, Sicherheit, Wirksamkeit, Vorhersagbarkeit, Stabilität sowie die Komplikationen der LASIK mit Scanning-Spot-Excimer-Technologie zu bewerten. Patienten und Methode. Hundert konsekutive LASIK-Operationen im Zeitraum zwischen 2/1998 und 2/1999 [60 Patienten im mittleren Alter von 37 Jahren (Spannbreite: 20–55 Jahre)] wurden ausgewertet. Als Schnittgerät für die Keratomileusis wurde das Hansatome™ Mikrokeratom mit superiorem Hinge eingesetzt (Flapdurchmesser: 9,5 mm), die Laserablation wurde mit einem Scanning-Spot-Excimerlaser (Technolas-C-Lasik-217) durchgeführt. Das sphärische Äquivalent der subjektiven manifesten Refraktion lag im Mittel bei −6,96±2,87 dpt, die mittlere Sphäre bei −6,47±2,71 dpt, der mittlere Astigmatismus bei −0,98±0,94 dpt. Vor der Behandlung erreichten 6% der Augen mit bester Korrektur nur einen Visus von 0,5. Kontrolluntersuchungen fanden präoperativ, nach 1 und 7 Tagen sowie nach 1, 4 und 12 Monaten statt. Sicherheit, Wirksamkeit, Vorhersagbarkeit, Stabilität der refraktiven Werte sowie die Komplikationen wurden mit der Datagraph-Software (Version 1.11) ausgewertet. Ergebnisse. Am ersten postoperativen Tag und nach einer Woche konnten alle 100 Augen nachuntersucht werden, nach einem Monat 96, nach vier Monaten 95 und nach einem Jahr 92 Augen. Nach einem Jahr verlor kein Auge zwei oder mehr Zeilen an Sehvermögen, 99% lagen im Bereich von ±1 Zeile und 1% gewann 2 Zeilen (Sicherheitsindex: 1,03). Es erreichten 92% aller Augen einen unkorrigierten Visus von ≥0,5, 77% ≥0,8 und 51% von ≥1,0 (Wirksamkeitsindex: 0,89); 60 Augen (65,21%) lagen im Bereich von ±0,5 dpt, 82 Augen (89,13%) im Bereich von ±1,0 dpt und 91 Augen (98,91%) im Bereich von ±2,0 dpt. Das mittlere sphärische Äquivalent betrug nach einem Jahr −0,15±1,31 dpt. Zwischen 1 und 12 Monaten zeigte sich eine mittlere Regression von −0,14 dpt. Auf Wunsch der Patienten wurden 5 Augen während der Studienperiode wegen Unter- oder Überkorrektur nachbehandelt. Schnittkomplikationen traten nicht auf. Hornhautinfektionen wurden nicht verzeichnet, eine diffuse lamelläre Keratitis (DLK) wurde 12-mal beobachtet, aber alle Fälle heilten komplikationslos ab. Bei 7 Augen kam es zu einer leichten Dezentrierung (<1 mm) der Ablation, die in einem Fall zu einer erhöhten Blendempfindlichkeit führte. Schlussfolgerung. Die LASIK-Operation mit superiorem Hinge und Scanning-Spot-Excimer-Photoablation ist zur refraktiven Behandlung von Myopie (bis maximal −12 dpt) und myopischem Astigmatismus (bis maximal −5 dpt cyl.) geeignet. Die refraktiven Ergebnisse zeigten über den Verlauf des 12-monatigen Untersuchungszeitraums hohe Stabilität. Die Vorhersagbarkeit der refraktiven Ergebnisse lässt sich weiter verbessern.AbstractPurpose. Recently laser-in-situ-keratomileusis (LASIK) has been increasingly used to correct refractive errors. The purpose of this investigation was to evaluate the safety, efficacy, predictability, stability and complications using the scanning spot excimer LASIK technology. Patients and methods. The results of 100 consecutive LASIK operations carried out between 2/1998 and 2/1999 on 60 patients (mean age 37 years, range 20–55 years) have been evaluated. The Hansatome™ microkeratome with a superior hinge (flap diameter: 9.5 mm) and a scanning spot excimer laser (Technolas C-Lasik 217) were used in all cases. The mean spherical equivalent of the subjective manifest refraction was −6.96±2.87 diopters (D), the mean sphere was −6.47±2.71 D and the mean astigmatism was −0.98±0.94 D. In 6% of the eyes preoperative visual acuity was not better than 20/40. Examinations were performed preoperatively, after 1 and 7 days, after 1, 4 and 12 months. Safety, efficacy, predictability, stability and complications were calculated using the datagraph software (version 1.11). Results. All 100 eyes were examined after 1 day and 1 week, 96 after 1 month, 95 after 4 months and 92 after 1 year. Following 1 year none of the eyes lost 2 or more lines of best corrected visual acuity, 99% were within ±1 line and 1% gained 2 lines (safety index 1.03). In 92% of all eyes an uncorrected visual acuity of ≥0.5 was reached, in 77% ≥0.8 and in 51% ≥1.0 (efficacy index 0.89). For 60 eyes (65.21%) a refractive correction of±0.5 D was necessary, for 82 eyes (89.13%) ±1.0 D and for 91 eyes (98.91%) ±2.0 D. The mean spherical equivalent after 1 year was −0.15±1.31 D. Between 1 and 12 months a mean regression of −0.14 D occurred. On the request of the patients, 5 eyes were retreated during the study period for under- or overcorrection. Complications due to the microkeratome did not occur. Corneal infections were not observed, a diffuse lamellar keratitis (DLK) was seen in 12 cases, but all cases healed with no loss of visual acuity. In 7 eyes a slight decentration of the ablation was observed using corneal topography, which in one case caused an increase in glare sensitivity. Conclusions. LASIK with superior hinge and scanning spot excimer photoablation is suitable for the correction of myopia (up to a maximum of −12 D) and for myopic astigmatism (up to a maximum of −5 D). The refractive results showed a high stability during the 12-month study period but there is still room for improvement of the predictability.

Intraindividueller Vergleich von Intraokularlinsen aus hochrefraktivem Silikon (Allergan SI40NB) und hydrophobem Acrylat (Alcon Acrysof MA60BM) 1-Jahresergebnisse

ZusammenfassungHintergrund. Die Biokompatibilität von Intraokularlinsen aus unterschiedlichen faltbaren Materialien (hochrefraktives Silikon- und hydrophobes Acrylatmaterial) sollte im intraindividuellen Vergleich untersucht werden. Material und Methoden. In einer prospektiven, randomisierten Studie wurden 35 Patienten beidseits mittels selbstdichtender Tunnelinzision und Phakoemulsifikation operiert. Nach Randomisierung wurde in ein Auge eine faltbare Intraokularlinse mit 6-mm-Optik aus hochrefraktivem Silikon (Allergan SI40NB) und in das andere eine faltbare Intraokularlinse mit 6-mm-Optik aus hydrophobem Acrylatmaterial (Alcon Acrysof MA60BM) implantiert. Postoperative Kontrolluntersuchungen fanden nach 7 Tagen, 1–3 und 6 Monaten sowie 1 Jahr statt. Ergebnisse. Die Patienten erreichten nach 1–3 Monaten ein bestkorrigiertes Sehvermögen von 0,9±0,12/0,89±0,13 (SI40NB/MA60BM), dieses lag nach 1 Jahr bei 0,9±0,12/0,87±0,14 (SI40NB/MA60BM). Es zeigte sich kein signifikanter Unterschied beim errmittelten Endothelzellverlust. Die Laserflare-Werte (photon counts/ms) stiegen nur im frühpostoperativen Bereich (7 Tage) geringfügig an (SI40NB/MA60BM: 14,2±8,68/15,49±7,2; statistisch nicht signifikant). Nach 3 Monaten lagen diese Werte wieder im Normbereich. Die mittlere Dezentrierung (in mm) lag 1 Jahr postoperativ bei 0,29±0,14/0,3±0,15 (SI40NB/MA60BM). Vierzig Prozent der MA60BM-IOLs zeigten in der Scheimpflug-Spaltaufnahme “Glistenings”. Nach 1 Jahr wurde kein signifikanter Unterschied in der Nachstarbildung (Scheimpflug-Analyse) gefunden. Schlussfolgerung. Ein Jahr nach der Implantation faltbarer hochrefraktiver Silikon- und hydrophober Acrylatintraokularlinsen über eine Tunnelinzision nach Phakoemulsifikation ergaben sich hinsichtlich funktioneller und morphologischer Aspekte im intraindividuellen Vergleich zufrieden stellende Resultate ohne signifikante klinische Unterschiede zwischen den beiden faltbaren IOL.AbstractBackground. A prospective, randomized study was performed to evaluate intraindividually the biocompatibility of foldable, highly refractive silicone and hydrophobic acrylic intraocular lenses (IOL). Materials and methods. We studied 35 patients who underwent phacoemulsification using a self-sealing tunnel incision. In a randomized fashion one eye received a 6-mm optic IOL made of high-refractive index silicone (Allergan SI40NB) and the other eye a hydrophobic acrylic 6-mm optic IOL (Alcon AcrySof MA60BM). All patients were examined 7 days, 1–3 and 6 months, and 1 year postoperatively. Results. The mean best-corrected visual acuity (BCVA) was 0.9±0.12 vs. 0.89±0.13 (SI40NB vs. MA60BM) after 1–3 months. One-year postoperatively BCVA was still 0.9±0.12 vs. 0.87±0.14. The flare values (photon counts/ms) increased slightly 7 days after surgery (14.2±8.68 vs. 15.49±7.2, n.s.). Three months after surgery these values were again in the normal range. The mean IOL decentration was 0.29±0.14 vs. 0.3±0.15 mm 1 year postoperatively. Scheimpflug slit photography showed 40% of MA60BM IOLs to have “glistenings.” No significant difference regarding posterior capsular opacification was found. Conclusion. One year after implantation of foldable, highly refractive silicone and hydrophobic acrylic IOLs using a self-sealing tunnel incision and phacoemulsification, no significant functional or morphological differences between the two IOL types were observed.

Photorefraktive/photoastigmatisch-refraktive Keratektomie bei niedriger Myopie und myopem Astigmatismus Broad-beam- versus Scanning-spot-Lasertechnologie

ZusammenfassungHintergrund. Die refraktiven Ergebnisse nach photorefraktiver/photoastigmatisch-refraktiver Keratektomie zweier konsekutiv mit unterschiedlichen Excimer-Lasersystemen behandelten Patientengruppen wurden verglichen. Patienten und Methoden. Mit dem Ganzfeldlasersystem VISX 20/20 wurden 46 Augen mit dem Scanning-Spot-Lasersystem Keracor 217 49 Augen behandelt. Die präoperative subjektive manifeste Refraktion betrug in beiden Patientengruppen im sphärischen Äquivalent ≤−6,0 dpt. Sicherheit, Wirksamkeit, Vorhersagbarkeit, Stabilität und Komplikationen wurden 1, 4 und 12 Monate postoperativ untersucht. Ergebnisse. Von den mit dem Ganzfeldlaser behandelten Patienten verlor 12 Monate postoperativ kein Auge 2 oder mehr Zeilen des bestkorrigierten Visus, während in der mit dem Scanning-spot-Laser behandelten Gruppe 1 Auge einen bestkorrigierten Visusverlust von 2 Zeilen erlitt. Bezüglich Wirksamkeit, Vorhersagbarkeit und Stabilität ergaben sich vergleichbare Ergebnisse in den beiden Behandlungsgruppen. Schlussfolgerung. Beide Lasertechniken zeigten bei der PRK-Behandlung von niedrigen Myopien und myopischen Astigmatismen gute Ergebnisse und wiesen keine grundlegenden Unterschiede auf.AbstractPurpose. The results of photorefractive/photoastigmatic refractive keratectomy (PRK/PARK) were compared between two patient groups treated consecutively with either broad-beam or scanning-spot technology. Patients and methods. PRK/PARK was performed with a broad-beam excimer laser VISX 20/20 in 46 eyes and with the scanning-spot laser system Keracor 217 in 49 eyes. Preoperative spherical equivalent (subjective manifest refraction) was ≤−6.0 diopter in both groups. Safety, efficacy, predictability, stability, and complications were investigated after 1, 4 and 12, months postoperatively. Results. In the broad-beam laser group no eye lost two or more lines of best-corrected visual acuity; in the scanning-spot laser group one eye lost two lines 12 months postoperatively. Efficacy, predictability, and stability were comparable between the two groups. Conclusions. Both the broad-beam and the scanning-spot laser provided good results after PRK/PARK for low myopia and myopic astigmatism. This study found no fundamental differences between the two laser systems.

Results of correction of myopic astigmatism with the VISX 20/20 excimer laser

SummaryThe 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.ZusammenfassungHintergrund: Die photo-astigmatisch-refraktive Keratektomie (PARK) mittels Excimerlaser bei myopem Astigmatismus ist eine noch kontrovers diskutierte Methode. Die Refraktionsergebnisse wurden 6 und 12 Monate postoperativ ermittelt, um die Genauigkeit und Stabilität der Behandlung eines myopen Astigmatismus mit dem VISX 20/20 Excimerlaser feststellen zu können. Patienten und Methode: Bisher wurden 31 Augen von 22 Patienten wegen eines myopen Astigmatismus behandelt. 6 Monatsergebnisse liegen von allen Augen, 12 Monatsergebnisse von 18 Augen vor. Es wurden gleichzeitig Korrekturen der Myopie und des Astigmatismus vorgenommen. Die Myopie wurde von −1,5 bis −10,0 dpt und gleichzeitig der Astigmatismus von −0,5 bis −5,5 dpt korrigiert, so daß sich Korrekturen mit einem sphärischen Äquivalent von −1,75 bis −10,5 dpt ergaben. Ergebnisse: Innerhalb des Zielrefraktionsbereiches von ± 1,0 dpt lagen 6 Monate postoperativ 21/31 (62 %) und innerhalb von ± 0,5 dpt 13/31 (42 %) der Augen. Bei Korrekturen unter −6,0 dpt erreichten 13/15 (87 %) der Augen eine unkorrigierte Sehschärfe von mindestens 0,8. Bei Korrekturen über −6,0 dpt hatten 9/16 (56 %) eine unkorrigierte Sehschärfe von mindestens 0,5. Nach 6 Monaten wurde eine Visusverbesserung um 1 Visusstufe bei 8/31 (25,8 %), um 2 Stufen bei 3/31 (9,7 %) und um 3 Stufen bei einem Auge (3,2 %) festgestellt. Visusverschlechterungen um mehr als zwei Visusstufen fanden wir bei 3/31 Augen (9,7 %). Der Betrag des Astigmatismus war im Mittel postoperativ statistisch signifikant von prä-operativ 1,93 ± 1,43 dpt auf postoperativ 0,9 ± 0,63 dpt vermindert. Bei Astigmatismuskorrekturen unter −1,25 dpt erreicht man keine signifikante Reduktion, bei einem Astigmatismus zwischen −1,25 bis −5,5 dpt ergab sich eine Reduktion um im Mittel 60 % des Ausgangswertes. Bei der Myopiekorrektur fand sich bis 6 Monate postoperativ bei 9/31 (29 %) Augen eine Regression zwischen 1,0 und maximal 3,375 dpt. Für den Astigmatismus zeigte sich 3 Monate postoperativ nur noch eine geringe Regressionstendenz. Änderungen der Astigmatismusachse größer 15 ° fanden wir 6 Monate postoperativ bei subjektiver Refraktion (Miosis/Zykloplegie) in 42 %/35 % und in der Hornhauttopographie (TMS) bei 33 % der Augen. Central islands traten bei diesen Behandlungen nicht auf. Schlußfolgerung: Die PARK eignet sich zur Reduzierung des myopen Astigmatismus. Bei Werten über −1,0 dpt ergibt sich im Mittel eine Verminderung um 60 % des Ausgangswertes. Der hohe Anteil an postoperativen Achsenabweichungen um mehr als 15 ° sowie die Rate der Visusverschlechterungen um zwei oder mehr Visusstufen erfordern jedoch eine Verbesserung der Achslagenkontrolle während der Behandlung, sowie eine Optimierung der Korrekturprogramme. Ob eine weiterentwickelte Lasertechnik (z. B. flying-spot laser) bessere Ergebnisse bringt, bleibt abzuwarten.UNLABELLED 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 degrees 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 degrees 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.

Book Review · Livre nouveau · Buchbesprechung

This book deals with animal studies on corneal graft rejection. The introduction presents the current state of knowledge of allograft reaction after experimental keratoplasty and focuses on immunomodulated therapy with encapsulated monoclonal antibodies (mAb) in local application. In the second chapter, the goals and reasons for a study on the prevention of allograft rejection by local treatment with mAb are given in the form of four questions: (1) can locally applied CD4 mAb affect graft reaction after penetrating keratoplasty? (2) are liposome-incorporated CD4 mAb more effective? (3) do locally applied CD4 mAb have a systemic effect? (4) does the recipient react systemically against graft antigens and are in vitro tests meaningful for clinical grafts? Materials, methods and results are clearly described in the third and fourth chapters. In an experimental model of penetrating keratoplasty in rat eyes, anti-CD4 mAb were injected subconjunctivally or applied as drops in two different forms of administration selected for free mAb in a first test series and liposome-encapsulated mAb in a second. The results of liposome-encapsulated mAb application showed a declining incidence of immunologic graft reactions after subconjunctival injection and also after drop application. The controls showed no effects. A systemic effect on CD4+ lymphocytes could be excluded by flow cytometry. The cytotoxic T lymphocyte activity tested by antigen-specific cytotoxic T lymphocyte in vitro tests was significantly elevated after allograft reactions as an indication of specific sensitization. In contrast to this, no delayed-type hypersensitivity response was observed in the present study. These results are discussed in detail in the fifth chapter. In summary, the results described in this book open up new perspectives for preventing allograft reactions after keratoplasty by local application of liposome-encapsulated specific mAb. These exciting animal results should proceed to clinical trials in the near future.