Terrance J Kasper

Refractive Surgery Survey 2001.

&NA; To determine the refractive surgery preferences of ophthalmologists worldwide, questionnaires were sent to 8920 members of the American Society of Cataract and Refractive Surgery. A total of 1174 questionnaires was returned by the deadline. The practice distribution included 30.0% cataract surgeons, 47.3% comprehensive ophthalmologists, 14.4% refractive surgery (RS) specialists, 4.5% corneal/external disease specialists, 1.9% glaucoma specialists, and <1% retinal/oculoplastics/pediatrics/neurophthalmologists/researchers/retired. Responses were compared with those in the 2001 and 2002 surveys and demonstrate that RS practice patterns continue to evolve.

Flap thickness accuracy ☆ ☆☆ ★ ★★: Comparison of 6 microkeratome models

Purpose: To determine the flap thickness accuracy of 6 microkeratome models and determine factors that might affect flap thickness. Setting: Magill Research Center for Vision Correction, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. Methods: This multicenter prospective study involved 18 surgeons. Six microkeratomes were evaluated: AMO Amadeus, Bausch & Lomb Hansatome®, Moria Carriazo‐Barraquer, Moria M2, Nidek MK2000, and Alcon Summit Krumeich‐Barraquer. Eyes of 1061 consecutive patients who had laser in situ keratomileusis were included. Age, sex, surgical order (first or second cut), keratometry (flattest, steepest, and mean), white‐to‐white measurement, laser used, plate thickness, head serial number, blade lot number, and occurrence of epithelial defects were recorded. Intraoperative pachymetry was obtained just before the microkeratome was placed on the eye. Residual bed pachymetry was measured after the microkeratome cut had been created and the flap lifted. The estimated flap thickness was determined by subtraction (ie, mean preoperative pachymetry measurement minus mean residual bed pachymetry). Results: A total of 1634 eyes were reviewed. Sex distribution was 54.3% women and 45.7% men, and the mean age was 39.4 years ± 10.6 (SD). In addition, 54.5% of the procedures were in first eyes and 45.5%, in second eyes. The mean preoperative pachymetry measurement was 547 ± 34 &mgr;m. The mean keratometry was 43.6 ± 1.6 diopters (D) in the flattest axis and 44.6 ±1.5 D in the steepest axis. The mean white‐to‐white measurement was 11.7 ± 0.4 mm. The mean flap thickness created by the devices varied between head designs, and microkeratome heads had significant differences (P<.05). Factors that explained 78.4% of the variability included microkeratome model, plate thickness, mean preoperative pachymetry, Kmin, surgery order, head serial number, blade lot number, and surgeon. Factors such as age, sex, Kmax, Kaverage, white to white, and laser had no significant correlation to flap thickness. Conclusions: The results demonstrated variability between the 6 microkeratome models. Device labeling did not necessarily represent the mean flap thickness obtained, nor was it uniform or consistent. Thinner corneas were associated with thinner flaps and thicker corneas with thicker flaps. In addition, first cuts were generally associated with thicker flaps when compared to second cuts in bilateral procedures.

Effect of hinge location on corneal sensation and dry eye after laser in situ keratomileusis for myopia

PURPOSE: To evaluate the effects of a superior or nasal hinge location on corneal sensation and dry eye after laser in situ keratomileusis (LASIK). SETTING: Magill Research Center for Vision Correction, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: This prospective randomized masked study included 47 patients having bilateral myopic LASIK surgery. The first eye was randomly assigned to have a nasal or superior hinge flap; the fellow eye had the alternate location. Visual acuity, contrast sensitivity, corneal sensation, basic secretion test, tear film breakup time, conjunctival and corneal staining, and a subjective questionnaire were evaluated preoperatively and postoperatively at 1 week and 1, 3, and 6 months. The Wilcoxon signed rank test and paired t test were used for comparison. RESULTS: Dry eye occurred with the same frequency in both groups. However, eyes with the nasal hinge had significantly better nasal sensation than those with the superior hinge (P<.05) at 1 month. CONCLUSION: Better nasal corneal sensation was found at 1 month in the nasal hinge group but there was no difference in any other parameters measured.

Diffuse lamellar keratitis: evaluation of etiology, histopathologic findings, and clinical implications in an experimental animal model☆

Purpose: To induce diffuse lamellar keratitis (DLK) and investigate the potential causative agents in an animal model. Setting: Magill Research Center for Vision Correction, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. Methods: In 70 eyes of 35 Dutch Belted rabbits, a corneal flap was cut and the interface randomly exposed to 1 of 7 substances: Pseudomonas aeruginosa endotoxin, 1 of 2 Staphylococcus aureus exotoxins, meibomian gland secretion, povidone−iodine 10%, Palmolive® Ultra soap, and Klenzyme® soap. Slitlamp examinations were performed 1, 3, 5, and 7 days postoperatively. The DLK was staged from 1 to 4. On day 7, the rabbits were killed and the eyes enucleated and processed for histopathologic examination. Results: At the end of the study, 54 eyes (46 exposed, 8 control) were available for evaluation. The 8 eyes studied concurrently in the control group remained clear and did not show interface inflammation. Thirty‐one of 46 eyes (67%) treated with the various test substances developed DLK. The highest DLK rates were found with the cleaning soap Palmolive Ultra (100%; P = .022) and P aeruginosa lipopolysaccharide endotoxin (90%; P = .026). Conclusions: Interface inflammation was consistently induced in the animal model. All 7 agents caused DLK in at least some eyes. The histopathologic evaluation showed the morphologic profile of the marked inflammatory cellular reaction that occurred in almost all the specimens.

Corneal flap complications in refractive surgery

Purpose: To induce diffuse lamellar keratitis (DLK) and investigate a prophylactic treatment with pharmacological agents. Setting: Magill Research Center for Vision Correction, Storm Eye Institute, Charleston, South Carolina, USA. Methods: In 100 eyes of 50 Dutch Belted rabbits, a nasal corneal flap was cut and the interface inoculated with Pseudomonas aeruginosa lipopolysaccharide endotoxin (n = 50) or Palmolive® Ultra soap (n = 50). The eyes were randomly assigned to treatment with a mast‐cell stabilizer, a nonsteroidal antiinflammatory drug (NSAID), a fluoroquinolone antibiotic agent, a corticosteroid, or left without treatment as a control. Slitlamp examinations and photographs were performed 1, 3, 5, and 7 days postoperatively, and DLK was graded by a masked observer from 0 (no DLK) to stage 4. Results: At the end of the study, 80 eyes were available for evaluation. Ninety‐four percent of the untreated eyes developed DLK compared to 56% of eyes treated with NSAIDs and 63% of eyes treated with steroids (P<.05, Fisher exact test). The DLK rates with the mast‐cell stabilizer and fluoroquinolone antibiotic agent were 86% and 76%, respectively. The DLK incidence in the latter 2 groups was not significantly different from that in the control eyes (P>.05, Fisher exact test). Conclusions: Postoperative prophylactic treatment with NSAIDs and corticosteroids led to a statistically significantly lower incidence of postoperative DLK. The study demonstrated that corticosteroids and NSAIDs can be used to treat DLK after LASIK. While steroids are a generally accepted treatment for DLK, NSAIDS may offer an additional potent modality.

Corneal flap complications in refractive surgery Part 1: Development of an experimental animal model

Purpose: To report the outcome, learning curve, and complication rates of an experimental animal model for corneal flaps in refractive surgery. Setting: Magill Research Center for Vision Correction, Storm Eye Institute, Charleston, South Carolina, USA. Methods: Corneal flaps with a nasal or a temporal hinge were created in 190 eyes of 95 Dutch Belted rabbits using the Automated Corneal Shaper® microkeratome (Bausch & Lomb Surgical). Diffuse lamellar keratitis (DLK) was induced by inoculating the corneal interfaces with 1 of 7 substances. Postoperatively, the eyes were examined with a slitlamp. Special emphasis was placed on corneal flap complications and the relationship between slipped flaps and hinge position and/or inoculation agent. Results: A good corneal flap was achieved in 174 eyes (92%). The eyes with a nasal hinge had a lower incidence of slipped flaps (14%) than eyes with a temporal hinge (37%) (P = .02). Conclusion: With the animal model described, corneal flaps were created in a precise and reproducible way in more than 90% of eyes. Nasal hinged flaps showed less postoperative displacements than temporal hinged flaps and are adequate for further study.

Diffuse lamelläre Keratitis

ZusammenfassungFragestellung. Ziel der experimentellen Studie war es, diffuse lamelläre Keratitis (DLK) im Kaninchenauge auszulösen und eine postoperative Prophylaxe mit Kortikosteroidaugentropfen zu evaluieren. Material und Methode. Eine Hornhautlamelle (Flap) wurde in 40 Augen von 20 pigmentierten Kaninchen geschnitten und anschließend das Hornhautstromabett mit Pseudomonas-aeruginosa-Lipopolysaccharid- (LPS-)Endotoxin (n=21) oder Palmolive® Ultra-Seife (n=19) in Kontakt gebracht. Postoperativ wurde die eine Hälfte der Augen mit Kortikosteroidaugentropfen behandelt, die andere Hälfte blieb unbehandelt. Spaltlampenuntersuchungen und Fotoaufnahmen wurden am 1., 3., 5. und 7. postoperativen Tag durchgeführt und DLK nach Schweregrad I–IV eingeteilt. Ergebnisse. Am Ende der Studie konnten 33 Kaninchenaugen ausgewertet werden. Von den unbehandelten Augen entwickelten 94% postoperativ DLK. Für die mit Kortikosteroiden behandelten Augen lag die DLK-Rate am 7. Tag bei 19%, was statistisch signifikant geringer war (p=0,018). Schlussfolgerung. Pseudomonas-aeruginosa-LPS-Endotoxin und Palmolive® Ultra verursachten in einer sehr hohen Rate DLK im Kaninchenauge. Die prophylaktische postoperative Behandlung mit Kortikosteroidaugentropfen führte in diesem experimentellen Tiermodell zu einer signifikant geringeren DLK-Rate.AbstractPurpose. The aim of this experimental ani-mal study was to induce diffuse lamellar keratitis (DLK), and investigate a prophylactic treatment with corticosteroids. Materials and methods. A corneal flap was cut in 40 eyes from 20 Dutch-belted rabbits and the interface inoculated with either Pseudomonas aeruginosa lipopolysaccharide (LPS) endotoxin (n=21) or Palmolive Ultra soap (n=19). Half of the eyes were treated with topical corticosteroids and the other half remained untreated. Slitlamp examinations were performed 1, 3, 5 and 7 days postoperatively and DLK was graded from I–IV. Results. At the end of the study 33 eyes were available for evaluation and 94% of the non-treated eyes developed DLK. Out of those eyes treated with steroids 19% deve-loped DLK during the 1 week follow-up period. This was statistically significantly lower (P=0.018) when compared to the untreated group. Conclusion.Pseudomonas aeruginosa LPS endotoxin as well as Palmolive® Ultra caused a very high rate of DLK in rabbit eyes. The postoperative prophylactic treatment with corticosteroids showed a statistically significant lower DLK rate in this rabbit eye model.

Evaluation of preoperative and postoperative prophylactic regimens for prevention and treatment of diffuse lamellar keratitis

Purpose: To investigate preoperative and postoperative prophylactic treatment with different pharmacological agents before flap cutting and exposure to a diffuse lamellar keratitis (DLK) causative agent. Setting: Magill Research Center for Vision Correction, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. Methods: The study comprised 48 eyes of 24 Dutch‐belted rabbits. Three days before a corneal flap was cut and the corneal interface was exposed to Pseudomonas aeruginosa lipopolysaccharide endotoxin, a DLK causative agent, the eyes were randomly assigned to treatment with a mast‐cell stabilizer, a nonsteroidal antiinflammatory drug (NSAID), or a corticosteroid or left without treatment as controls. The treatment was maintained throughout the 1‐week follow‐up. Slitlamp examinations and photographs were performed at 1, 3, 5, and 7 days; DLK was graded by a masked observer from 0 (no DLK) to IV. Corneal interface scrapings were performed in selected eyes on day 7. Results: At the end of the follow‐up, 36 eyes were available for evaluation. At 1 week, 100% of the control eyes and the eyes treated with the mast‐cell stabilizer developed DLK; in the NSAID‐treated and corticosteroid‐treated eyes, the DLK rate was 86% and 70%, respectively. At 1 day, the severity of DLK was significantly lower in eyes treated with the mast‐cell stabilizer (0.44) and at 7 days, it was significantly lower in corticosteroid‐treated eyes (0.3) than in the control group (1.5 and 1.4, respectively) (P<.05, Wilcoxon test). Corneal interface scraping from an eye with grade III DLK showed numerous inflammatory cells. Conclusions: Preoperative and postoperative treatment with corticosteroids significantly reduced the severity of DLK compared to the untreated control eyes in this animal model. Treatment with a mast‐cell stabilizer and an NSAID had less effect on the postoperative course of DLK.

Queratitis lamelar difusa: tratamiento profiláctico con ketorolaco trometamina 0,5% en un modelo animal

espanolObjetivo: El proposito de este estudio es evaluar el uso de un agente anti-inflamatorio, no esteroideo, en el tratamiento de la queratitis lamelar difusa inducida en un modelo animal. Materiales y Metodos: Se creo un flap corneal en 40 ojos de 20 conejos pigmentados con el microqueratomo ASC y la entrecara fue inoculada con endotoxina de Pseudomona aeruginosa o Palmolive® Ultra jabon liquido. Los conejos fueron divididos en dos grupos: El grupo I (n= 20) recibio tratamiento con Ketorolaco trometamina 0,5% solucion oftalmica 4 veces al dia y el grupo II o control (n= 20), sin tratamiento. Los conejos fueron examinados en la lampara de hendidura los dias 1, 3, 5 y 7 postoperatorios. La presencia de queratitis lamelar difusa fue clasificada de acuerdo a la severidad de I a IV. Resultados: Al final del estudio 31 ojos fueron evaluados. 28 ojos (90%) desarrollaron DLK: 86% de los que recibieron tratamiento y 94% del grupo control. El grupo tratado presento un menor porcentaje de DLK y la severidad tambien fue menor que en el grupo control. Sin embargo, no se encontro diferencia estadisticamente significativa al comparar los dos grupos (P > 0,05). Conclusion: Se ha demostrado que tanto la endotoxina LPS de Pseudomona aeruginosa como el Palmolive® Ultra jabon liquido pueden inducir DLK. El tratamiento profilactico con un agente anti-inflamatorio no esteroideo mostro una tendencia a disminuir tanto la presentacion de DLK como su severidad. EnglishPurpose: The objective of this study is to evaluate the use of a topical non-steroidal anti-inflammatory drug in the treatment of induced diffuse lamellar keratitis (DLK) in an animal model. Materials and Methods: A corneal flap was created in 40 eyes of 20 Dutch-belted rabbits using the ASC microkeratome. The interface was inoculated with either Pseudomonas Aeruginosa Lipopolysaccharide (LPS) endotoxin or Ultra Palmolive® liquid dish washer. The rabbits were divided in two groups: Group I (n=20) treated with ketorolac tromethamine ophthalmic solution 0.5% 4 times a day and the group II (n=20) used as control. The rabbits were examined at the slit lamp at day 1, 3, 5 and 7 postoperatively. DLK was graded from I-IV. Results: At the end of the study 31 eyes were available for evaluation. 28 eyes (90%) developed DLK: 86% of the treated group and 94% of the control group during the follow-up. The treated group showed a lower rate of DLK as well as a lower severity. However, no statistically significant difference was found when comparing both groups (P > 0.05). Conclusion: Pseudomonas aeruginosa LPS endotoxin and Palmolive® Ultra can induce DLK in rabbit eyes. The postoperative prophylactic treatment with a topical non-steroidal anti-inflammatory drug showed a tendency towards a lower DLK rate as well as the severity of the disease.