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Mike P Holzer

Publications and source records attributed to Mike P Holzer.

At least 19 recordsLinked to original sources
PubMed2007

Long-term results of sealed capsule irrigation using distilled water to prevent posterior capsule opacification: a prospective clinical randomised trial.

BACKGROUND: We investigated long-term safety and efficacy of sealed capsule irrigation (SCI) during cataract surgery to prevent posterior capsule opacification (PCO). METHODS: One eye of each of 17 patients (mean age: 70.1+/-9.7 years) who presented with bilateral cataracts was randomly chosen for SCI treatment. After phacoemulsification, the capsular bag was vacuum sealed with the PerfectCapsule device (Milvella) followed by SCI using distilled water for two minutes. No vacuum loss occurred during irrigation. Each patient's fellow eye served as a control. One hydrophilic acrylic intraocular lens model was implanted in all eyes. Five patients had to be excluded due to deep anterior chamber, small pupil or unilateral surgery. Follow-up examinations took place one day and one, three, six, 12 and 24 months after surgery. We evaluated safety parameters, anterior capsule (AC) overlapping and PCO. RESULTS: Postoperatively, mean best corrected visual acuity, pachymetry, endothelial cell count, intraocular pressure, AC overlapping and PCO showed no statistically significant difference between SCI and the control group (p>0.05, Wilcoxon test). CONCLUSION: SCI is a safe procedure and enables the specific pharmacological targeting of lens epithelial cells inside the capsular bag. Using distilled water, however, it is not possible to reduce PCO development significantly. Thus, alternative substances should be evaluated.

Adult↗
PubMed2006

Femtosecond laser-assisted corneal flap cuts: morphology, accuracy, and histopathology.

PURPOSE: Precision in corneal flap cutting is essential in LASIK surgery. Current mechanical microkeratomes have a very good performance record; however, in a few cases, complications can occur during the microkeratome pass and flap cut. Femtosecond lasers offer an alternative to the mechanical cut and can provide additional features regarding the flap morphology. In this study, we analyzed femtosecond laser flaps regarding their morphology, cut accuracy, and histopathology. METHODS: Forty-five fresh porcine cadaveric eyes were prepared for femtosecond laser flap cutting with the Femtec femtosecond laser system (20/10 Perfect Vision, Heidelberg, Germany). The eyes were assigned to three different thickness groups, with 120-, 140-, or 180-microm cut depth, respectively. In addition, different flap diameters ranging from 8.0 to 9.5 mm and rim edge angulations between 60 degrees and 90 degrees were performed. After the cut, the eyes were examined under a microscope regarding accuracy and potential defects, and flap thickness and diameter were measured. In addition, flaps were prepared for further histopathologic examination. RESULTS: All flap cuts were easily performed without any intraoperative complications. Flap thickness measurements revealed a median (in micrometers) of 110.5 (intended thickness 120), 142.5 (intended 140), and 180.0 (intended 180), respectively. The flap diameter for an intended size between 8.0 and 9.5 mm was within a range of +/-0.4 mm, the median at the maximum was 0.3 mm off. Histopathology revealed very low to almost no changes in the stromal structure of the cornea and correct hinge angulations. CONCLUSIONS: LASIK flap cuts were easily performed without any complications. The accuracy and morphology were very precise and consistent. Histopathology revealed a smooth cut with hinge angulations, as expected.

Animals↗
PubMed2006

Reliability of corneal and total wavefront aberration measurements with the SCHWIND Corneal and Ocular Wavefront Analyzers.

PURPOSE: To evaluate the reliability of the SCHWIND Corneal and Ocular Wavefront Analyzers. METHODS: This study comprised 115 eyes of 58 healthy volunteers (26 [44.8%] women and 32 [55.2%] men) with no corneal or lenticular pathologies and normal visual acuity. All eyes underwent three consecutive measurements by one examiner with the Corneal Wavefront Analyzer and the Ocular Wavefront Analyzer (Hartmann-Shack principle). Corneal wavefront errors were calculated using the topography data, a standard eye model, and ray tracing. The reliability was tested for 2nd, 3rd, and 4th order aberrations as mean values of the standard deviations for all measurements. RESULTS: Mean patient age was 23 +/- 2.1 years. The mean refraction was -0.77 +/- 1.56 diopters (D) (range: +3.33 to -5.28 D). The repeatability test revealed a good reliability for both machines with a slightly better value for the Ocular Wavefront Analyzer for 3rd and 4th order higher order aberrations (P < .05, Wilcoxon test). CONCLUSIONS: Wavefront measurements of corneal and total optical aberrations performed with the Corneal Wavefront Analyzer and the Ocular Wavefront Analyzer have good reliability. Both measurements are recommended prior to any refractive surgery treatment.

Adult↗
PubMed2005

Performance of the 1CU accommodating intraocular lens in relation to capsulorhexis size.

PURPOSE: To assess the correlation between continuous curvilinear capsulorhexis (CCC) size and visual outcomes in patients with an accommodating intraocular lens (IOL). SETTING: Heidelberg IOL and Refractive Surgery Research Group, Department of Ophthalmology, Ruprecht-Karls-University of Heidelberg, Heidelberg, Germany. METHODS: Nineteen eyes had phacoemulsification and implantation of a 1CU accommodating IOL (HumanOptics AG). Three months after surgery, the uncorrected and best corrected distance and near visual acuities and the distance corrected near visual acuity were measured. Retroillumination photographs were taken to assess CCC size and centration and the amount of overlap between the CCC and IOL optic. The photographs were analyzed using Evaluation of Posterior Capsule Opacification system software. RESULTS: The mean age of the patients was 53.5 years (range 30 to 73 years). The mean uncorrected distance acuity improved from 0.05 preoperatively to 0.70 at 3 months and the best corrected near acuity, from 0.30 to 0.94. The mean postoperative distance corrected near acuity was 0.5 (range 0.1 to 1.0), which improved to 0.9 with near correction. The mean CCC size (4.3 mm) and amount of CCC decentration (0.35 mm) did not correlate with visual outcomes. However, there was a correlation between the amount of CCC-optic overlap (mean 35%; range 16% to 55%) and distance corrected near acuity (r = 0.641, P = .003). Distance corrected near acuity was better with less overlapping; that is, with a larger CCC. CONCLUSIONS: A larger capsulorhexis with less CCC-optic overlapping gave better near visual outcomes. Results indicate that an overlap between 25% and 35%, which correlates with a CCC between 4.5 mm and 5.0 mm, provides the best capsule strength without compromising accommodation with the single-piece 1CU IOL.

Accommodation, Ocular↗
PubMed2005

Combination of transepithelial phototherapeutic keratectomy and autologous serum eyedrops for treatment of recurrent corneal erosions.

PURPOSE: To evaluate the clinical outcomes after transepithelial phototherapeutic keratectomy (t-PTK) using an excimer laser and postoperative administration of autologous serum eyedrops. SETTING: Department of Ophthalmology, Ruprecht-Karls-University of Heidelberg, Heidelberg, Germany. METHODS: Twenty-five eyes of 25 patients with 3 to 12 recurrent corneal erosions were treated with t-PTK using the Schwind Keratom broad-beam excimer laser (Schwind). Routine therapy consisted of 2 pulses x 40 pulses (18.82 +/- 2.56 mum ablation). Postoperatively, autologous serum eyedrops were administered 6 times a day for 6 weeks. Postoperative outcomes and rate of recurrent erosions were evaluated. RESULTS: The median of the follow-up after t-PTK was 15.5 months (range 6 to 20 months), and the mean age of the patients was 40.6 years +/- 12.0 (SD). Twenty of 25 eyes (80%) recovered without further corneal erosion. Five eyes had 1 further erosion, which was treatable in 4 cases with autologous serum eyedrops without additional excimer laser treatment. One patient requested additional t-PTK treatment and recovered without further complications thereafter. CONCLUSIONS: Transepithelial phototherapeutic keratectomy is a safe and effective therapy for recurrent corneal erosions. Additional treatment with autologous serum eyedrops can support the healing process following corneal erosions and t-PTK and can be given as a long-term artificial tear treatment.

Adult↗
PubMed2005

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.

Adult↗
PubMed2004

Removal times and techniques of a viscoadaptive ophthalmic viscosurgical device.

PURPOSE: To analyze removal techniques for Healon5 (sodium hyaluronate 2.3%). SETTING: Center for Research on Ocular Therapeutics and Biodevices, Charleston, South Carolina, USA, and Department of Ophthalmology, Ruprecht-Karls-University, Heidelberg, Germany. METHODS: In a standardized laboratory setup, the Miyake-Apple posterior view video technique in human autopsy eyes was used to evaluate removal of an ophthalmic viscosurgical device (OVD) from capsular bags implanted with poly(methyl methacrylate), silicone, and acrylic intraocular lenses (IOLs). Healon5 was stained with fluorescein for better visualization. Open-sky preparation and an Alcon Legacy Series 20000 phaco machine with a flow rate of 25 mL/minute and a vacuum setting of +500 mm Hg (maximum irrigation/aspiration [I/A]) were used. With Technique 1, the I/A tip was placed on the center of the IOL and maximum aspiration was applied. With Technique 2 (modified rock 'n roll technique), the I/A tip was moved in quick circular movements on top of the IOL to break the OVD chains and facilitate aspiration. RESULTS: With Technique 1, the mean removal time was 59.0 seconds +/- 23.1 (SD) and with Technique 2, 23.6 +/- 10.3 seconds (P =.004). The removal time of Healon5 correlated with the IOL material. With Technique 2, removal was fastest with silicone IOLs (13.5 +/- 2.1 seconds) followed by PMMA IOLs (17.5 +/- 2.1 seconds). With acrylic IOLs, remnants of the OVD trapped behind the IOL optic resulted in a longer removal time of 34.1 +/- 1.2 seconds. CONCLUSIONS: Healon5 was completely removed from the capsular bag with the modified rock 'n roll technique. With acrylic IOLs, remnants can be trapped behind the optic and may be overlooked with an unstained OVD. Aspiration behind the optic is recommended with this IOL type.

Acrylic Resins↗
PubMed2004

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 microm. 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.

Adult↗
PubMed2004

Removal times for a dispersive and a cohesive ophthalmic viscosurgical device correlated with intraocular lens material.

PURPOSE: To investigate the removal times of ophthalmic viscosurgical devices (OVDs) with different intraocular lens (IOL) designs and materials. SETTING: Center for Research on Ocular Therapeutics and Biodevices, Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA, and Heidelberg IOL & Refractive Surgery Research Group, Department of Ophthalmology, Ruprecht-Karls-University of Heidelberg, Heidelberg, Germany. METHODS: In a standardized laboratory setup, the Miyake-Apple posterior view video technique was used to evaluate OVD removal from capsular bags in human autopsy eyes implanted with poly(methyl methacrylate) (PMMA), silicone, and acrylic IOLs. The cohesive OVD ProVisc (sodium hyaluronate 1.0%) and the dispersive OVD Viscoat (sodium hyaluronate 3.0% and chondroitin sulfate 4.0%) were stained with fluorescein for better visualization. The open-sky preparation and an Alcon Series 20000 Legacy phaco machine with a flow rate of 25 mL/min and a vacuum setting of +500 mm Hg (maximum irrigation/aspiration) were used. The time needed for complete removal of the cohesive and dispersive OVDs with each IOL type was measured and analyzed statistically. RESULTS: The mean removal times for both OVDs were as follows: Alcon MZ60BD PMMA IOL-25.0 seconds +/- 3.7 (SD) (Viscoat), 15.9 +/- 6.9 seconds (ProVisc); Alcon AcrySof MA60BM IOL-35.5 +/- 10.0 seconds (Viscoat), 25.6 +/- 4.7 seconds (ProVisc); Chiron/Bausch & Lomb C1043 silicone IOL-46.5 +/- 10.5 seconds (Viscoat), 17.3 +/- 2.1 seconds (ProVisc); AMO SI-30 silicone IOL-33.5 +/- 3.1 seconds (Viscoat), 15.3 +/- 6.3 seconds (ProVisc); and Pharmacia 912 silicone IOL-18.3 +/- 5.8 seconds (Viscoat), 19.8 +/- 4.3 seconds (ProVisc). CONCLUSIONS: Differences in OVD removal times were detected. The removal time for the cohesive OVD correlated with the IOL material. Overall, the time needed for complete removal was significantly longer for the dispersive OVD than for the cohesive OVD.

Acrylic Resins↗
PubMed2004

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.

Animals↗
PubMed2004

Endothelial cell integrity after phacoemulsification with 2 different handpieces.

PURPOSE: To investigate corneal endothelial cell loss in fresh phakic human autopsy cadaver eyes after phacoemulsification (PE) with a conventional handpiece or a new oscillatory handpiece. SETTING: Department of Ophthalmology, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: Twenty fresh phakic human autopsy globes were randomized to PE with a conventional handpiece (n = 10) or an oscillatory handpiece (n = 10). The main parameters evaluated were age, nucleus density, amount of ophthalmic viscosurgical device (OVD) used, and mean PE time and ultrasound (US) power. After surgery, the corneas were excised and the endothelia were vitally stained with trypan blue and alizarin red. Light microscopy was used to assess the endothelial cell loss. RESULTS: The mean age, density of the nucleus, OVD used, and US power were similar between the groups. The mean PE time was less with the NeoSoniX handpiece (0.71 minutes +/- 0.39 [SD]) than with the conventional handpiece (1.05 +/- 0.53 minutes). The mean number of dead endothelial cells was significantly lower in the oscillatory handpiece group (31.3 +/- 24.2 cells/mm(2)) than in the conventional handpiece group (60.4 +/- 46.8 cells/mm(2)) (P<.001, Mann-Whitney rank sum test). CONCLUSIONS: Less corneal endothelial cell loss occurred after PE with an oscillatory handpiece than with a conventional handpiece. Further randomized clinical trials are recommended to validate this study.

Adult↗
PubMed2003

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.

Animals↗
PubMed2003

Corneal flap complications in refractive surgery: Part 2: postoperative treatments of diffuse lamellar keratitis in an experimental animal model.

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.

Animals↗
PubMed2003

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.

Animals↗
PubMed2003

Residual cleaner after normal cleaning of laser in situ keratomileusis instruments.

PURPOSE: To determine whether residual cleaner could be detected in the rinse solution of surgical instruments after a standard cleaning protocol. SETTING: Magill Research Center for Vision Correction, Storm Eye Institute, Medical University of South Carolina, Charleston, South Carolina, USA. METHODS: The wavelength for maximum absorbance of 5 cleaners (Endozime) [The Ruhof Corp.], Enzol/Cidezyme [Advanced Sterilization Products], and Klenzyme [Steris Co.] enzymatic detergents; Palmolive Ultra dishwashing liquid [Colgate-Palmolive Co.]; and Universal concentrated surgical instrument cleaner and lubricant [B. Graczyk, Inc.]) was determined. Identically designed stainless-steel and titanium instruments were cleaned using a standardized protocol. Water temperatures of 25 degrees C (room temperature) or 40 degrees C (warm temperature) were used to rinse the instruments. The amount of residual cleaner in each rinse solution and remaining on each instrument at the completion of the cleaning procedure as a percentage of the total cleaner was determined. RESULTS: Residues of all cleaners were detected using a standard protocol involving rinse solutions at 25 degrees C. Increasing the temperature of the rinse solutions significantly reduced the cleaner residues (P<.05, Friedman repeated-measures analysis of variance on ranks test and Student-Newman-Keuls test) regardless of the instrument material. No significant difference was detected in the residual cleaners on stainless-steel and titanium instruments. CONCLUSIONS: Lower levels of cleaner residue were found on surgical instruments after a standard cleaning protocol using warm rinse water. Because cleaner residue has been reported to cause inflammation (eg, diffuse lamellar keratitis) after laser in situ keratomileusis (LASIK), it is advisable to use cleaners and cleaning protocols that result in acceptable cleaning without detectable levels of cleaner residue to avoid potentially harmful effects to the cornea after LASIK.

Analysis of Variance↗
PubMed2003

Photodynamic therapy with verteporfin in a rabbit model of corneal neovascularization.

PURPOSE: To determine the efficacy of photodynamic therapy (PDT) with verteporfin (Visudyne; Novartis AG, Basel, Switzerland) for treatment of corneal neovascularization in a rabbit eye model. METHODS: Corneal neovascularization was induced in Dutch belted rabbits by placing an intrastromal silk suture near the limbus. Verteporfin was administered by intravenous injection at a dose of 1.5 mg/kg, and the pharmacokinetics of verteporfin distribution in the anterior segment or PDT-induced (laser energy levels 17, 50, and 150 J/cm(2)) regression of corneal blood vessels were then determined. To assess PDT-induced toxicity of the anterior segment, corneal and iris/ciliary body histology, and IOP were evaluated after PDT. RESULTS: Verteporfin accumulation in vascularized regions of the cornea and the iris/ciliary body tissue were time dependent and maximum levels achieved at 60 minutes after injection. In rabbits, PDT of corneal vessels using laser energy of 17 or 50 J/cm(2) resulted in 30% to 50% regression of corneal neovascularization; however, in these animals, a rapid regrowth of new blood vessels occurred between 3 and 5 days. In the rabbits receiving PDT using laser energies of 150 J/cm(2), the mean vessel regression was 56%. During the nine days of the laser therapy follow-up period, no vessel regrowth was observed in these rabbits. Histologic examination of the anterior segment after PDT (150 J/cm(2)) showed localized degeneration of the corneal blood vessels without observable change in other anterior segment structures. CONCLUSIONS: These results provide evidence that PDT can produce significant regression of neovascular corneal vessels with no observable toxicity to the anterior segments. However, the optimal laser energy necessary to induce long-term regression (150 J/cm(2)) was three times that used to treat choroidal neovascularization.

Animals↗
PubMed2002

Epithelial downgrowth after clear cornea phacoemulsification: report of two cases and review of the literature.

OBJECTIVE: To report two cases of diffuse epithelial downgrowth after clear cornea phacoemulsification and to review the different treatment options for this ominous disease. DESIGN: Two interventional case reports. METHODS: Retrospective review of two eyes from two different patients in whom epithelial downgrowth developed 7 and 3 months after uneventful clear cornea phacoemulsification. In the first case, the epithelial invasion seemed to be growing from the temporal incision site onto the corneal endothelium toward the visual axis. Cryotherapy was applied to the affected cornea, with control of the growing membrane. A penetrating keratoplasty was performed to restore visual function. In the second patient, the membrane was attached to the iris and posterior cornea and was confirmed by diagnostic argon laser photocoagulation. This case was surgically treated with en bloc excision and a corneoscleral graft. MAIN OUTCOME MEASURES: Visual acuity at the final follow-up visit. RESULTS: Surgical treatment of the epithelial downgrowth was different for both patients. In the postoperative period, a best-corrected visual acuity of 20/60 and 20/30 was achieved in each case. No regrowth of the membrane was observed. CONCLUSIONS: Treatment of epithelial downgrowth is controversial. We present two cases of epithelialization of the anterior chamber with either clinical or histologic confirmation after clear cornea sutureless phacoemulsification. Surgical treatment should be attempted promptly to obtain a good visual prognosis.

Aged↗