Biomedical subjects

David R Hardten

Publications and source records attributed to David R Hardten.

25 records · Page 2Linked to original sources

PubMed2003

Loss of vision after laser in situ keratomileusis.

PURPOSE: To research the incidence of visual loss after laser in situ keratomileusis (LASIK). METHODS: We reviewed an extensive review of the literature published by The Ophthalmic Technology Assessment Committee of the American Academy of Ophthalmology regarding the safety and efficacy of LASIK. We also reviewed other recent literature. RESULTS: For low to moderate myopia and astigmatism, LASIK is efficient, safe, and predictable with few eyes losing two or more lines of best-corrected visual acuity (BCVA). For moderate to high myopia, the results are more variable and more eyes lost two or more lines BCVA. In both cases, this BCVA occurred in studies published on or before 1999. CONCLUSION: Serious adverse complications leading to significant visual loss are probably rare. Continued development of microkeratomes and laser technology are continuing to reduce the rare complications that do occur and improve functional outcomes and patient satisfaction.

Humans↗

PubMed2002

Lasik enhancements: a comparison of lifting to recutting the flap.

PURPOSE: To compare the visual outcomes and incidence of complications of lifting with recutting the lamellar flap in laser in situ keratomileusis (LASIK) enhancement surgery. DESIGN: Retrospective case-control study. PARTICIPANTS: Two hundred twelve consecutive eyes undergoing a LASIK enhancement procedure at a single surgery location during a 5-year period. METHODS: Charts of participants were obtained and outcome measures obtained. MAIN OUTCOME MEASURES: Uncorrected visual acuity, best-corrected visual acuity, refractive error, complications. RESULTS: Relifting of flaps was performed in 164 of 212 eyes (77.4%), and recutting of flaps was performed in 48 of 212 eyes (22.6%). There were no significant differences in early visual outcomes between the two groups. At 1 year patients had significantly better uncorrected vision if the flap was lifted rather than recut (20/24.7 vs. 20/31.3, P < 0.008). In addition, the flap lift group had a significantly more stable refraction at 1 year than did the recut group (change in spherical equivalent: +0.05 diopters (D) vs. -0.57 D). The incidence of complications did not significantly differ between the two groups. CONCLUSIONS: LASIK enhancement surgery can be performed safely and effectively by either lifting or recutting a flap. Lifting the flap may show better long-term stability of refractive error and uncorrected acuity.

Adult↗

PubMed2002

Long-term analysis of LASIK for the correction of refractive errors after penetrating keratoplasty.

PURPOSE: To determine the long-term safety and effectiveness of laser-assisted in situ keratomileusis (LASIK) in the treatment of refractive errors following penetrating keratoplasty. METHODS: A retrospective review was done of 57 eyes of 48 patients with anisometropia or high astigmatism who were unable to wear glasses or a contact lens after penetrating keratoplasty and who underwent LASIK for visual rehabilitation. Uncorrected visual acuity (UCVA), best spectacle-corrected visual acuity (BCVA), and corneal transplant integrity were recorded before surgery as well as up to 60 months after LASIK. RESULTS: The mean follow-up after the LASIK was 21.4 +/- 14.2 months (range, 3-60 months). Mean preoperative spherical equivalent (SE) was -4.19 +/- 3.38 diopters (D). Mean preoperative astigmatism was 4.67 +/- 2.18 D. Preoperative BCVA was 20/40 or better in 42 eyes (74%). At 2 years the mean SE was -0.61 +/- 1.81 D and mean astigmatism was 1.94 +/- 1.35 D for the 28 eyes with follow-up. UCVA was 20/40 or better in 12 eyes (43%), and BCVA was 20/40 or better in 24 eyes (86%) at 2 years. A gain in BCVA of one line or more was seen in eight eyes (29%). Two eyes (7%) had loss of two or more lines of BCVA at 2 years. Nine eyes (16%) developed epithelial ingrowth. Five eyes (9%) in this series had repeat corneal transplants. CONCLUSIONS: LASIK is effective for reducing ametropia after penetrating keratoplasty. Proper patient counseling is necessary because the results of LASIK after penetrating keratoplasty are not as good as, and complications are more frequent than, in eyes with naturally occurring myopia and astigmatism. Complications are especially common in patients with mismatch of the donor and host cornea and in those with poor endothelial cell function.

Adult↗

PubMedDate not supplied

Nomogram considerations with the Technolas 217A for treatment of myopia.

PURPOSE: To determine whether surgeon-specific nomogram adjustments are useful when using the Technolas 217A excimer laser for treating myopia and myopic astigmatism. METHODS: We conducted a prospective evaluation of 216 consecutive eyes with 6 months follow-up after treatment of myopia or myopic astigmatism with the Technolas 217A laser. Attempted vs. achieved change in refraction was analyzed with a statistical analysis software program. Factors such as age, corneal thickness (pachymetry), preoperative spherical equivalent refraction, preoperative cylinder, and optical zone were studied to evaluate their role in predicting refractive outcome at 6 months after LASIK. RESULTS: The mean value of attempted spherical equivalent refraction was -5.32 +/- 2.72 D. The mean achieved refractive correction at 6 months was -5.55 +/- 2.78 D, with a mean spherical equivalent of 0.13 +/- 0.54 D. The percent achieved effect at 1 month was 105%, and at 6 months, 103%. Preoperative spherical equivalent refraction and optical zone size were strong predictors of 6-month LASIK outcome. There was a 9% difference in the percent achieved effect between a 4 and 7-mm optical zone. There was no correlation between age, preoperative cylinder, or surgeon and 6-month outcome. CONCLUSIONS: Surgeons using the planoscan software on the Technolas 217A may experience a small initial overcorrection. There may be a benefit to reducing the treatment given with larger optical zones and smaller corrections.

Adult↗

PubMedDate not supplied

Peripheral keratitis following laser in situ keratomileusis.

PURPOSE: To report two different cases of sterile, peripheral keratitis following laser in situ keratomileusis (LASIK). METHODS: A report of two cases (two eyes of two patients). RESULTS: In two patients, peripheral infiltrates appeared 1 day after LASIK. One patient had a history of rheumatoid arthritis and both had peripheral corneal changes that may have represented prior inflammatory events. The presentations were quite different, with one occurring in association with an epithelial defect at the edge of the flap and the other occurring without an epithelial defect peripheral to the microkeratome cut. In the second case a similar infiltrate showed up in the unoperated fellow eye. Both patients were treated with aggressive antibiotic and corticosteroid therapy. Both patients recovered well with no loss of best spectacle-corrected visual acuity. CONCLUSION: Peripheral keratitis can occur in patients following LASIK; preoperative evidence of previous inflammation may be a marker for patients at higher risk. Rheumatoid arthritis patients may be at increased risk for this complication. With careful and aggressive management excellent visual outcomes are still possible.

Adult↗

PubMedDate not supplied

Triptans and the incidence of epithelial defects during laser in situ keratomileusis.

PURPOSE: To investigate whether the incidence of epithelial defects during laser in situ keratomileusis (LASIK) was different in patients who were taking sumatriptan (Imitrex, Glaxo Smith Kline, Pittsburgh, Pa) for migraine headaches than in those who were not. METHODS: A retrospective chart review was performed on 54 eyes of 28 patients who had been identified as taking sumatriptan and had undergone LASIK at Minnesota Eye Consultants between 1999 and 2001. These patients were compared with 54 gender- and age-matched control eyes operated on with the same microkeratome at the same location during the same period of time. The incidence of epithelial defects during LASIK was compared between the two groups. RESULTS: In the sumatriptan group, 11.1% (6 of 54) of eyes developed epithelial defects as compared to 9.3% (5 of 54) of eyes in the non-triptan group (P=.75, chi square). More recent sumatriptan exposure did not increase the incidence of epithelial defect (P=.47). In patients in whom sumatriptan was stopped >1 month prior to LASIK, 6.3% (1 of 16 eyes) had epithelial defects; in patients in whom sumatriptan was stopped <1 month prior to LASIK, 14.3% (4 of 28 eyes) developed epithelial defects; and 9.3% (5 of 54 eyes) of patients in whom no triptans had ever been used had epithelial defects (P=.70). CONCLUSIONS: There is no correlation between the use of sumatriptan for relief of migraine headaches and the generation of epithelial defects during LASIK. There appears to be no reason to stop triptans before proceeding with LASIK.

Adult↗

PubMedDate not supplied

Alcohol and mechanical scraping for epithelial ingrowth following laser in situ keratomileusis.

PURPOSE: To determine whether the use of 70% isopropyl alcohol is useful as an adjunct to simple mechanical removal of epithelial ingrowth following laser in situ keratomileusis (LASIK). METHODS: A retrospective comparison of two techniques of epithelial ingrowth removal following LASIK was performed. A total of 38 procedures on 31 patients were included. In one group, the epithelium was removed using a simple mechanical scraping technique and in the other, a similar technique combined with the application of 70% isopropyl alcohol was used. The rates of recurrence in the two groups were compared using a chi-square analysis. RESULTS: The total incidence of epithelial ingrowth recurrence in both groups was 57.9% (22/38). The incidence of clinically significant ingrowth recurrence in both groups was 34.2% (13/38). In the scrape group, the recurrence of any ingrowth was 43.8% (7/16) and the recurrence of clinically significant ingrowth was 31.3% (5/16). In the alcohol group, these rates were 68.2% (15/22) and 36.4% (8/22), respectively. The difference between the two groups did not show statistical significance in either comparison (P=.14 and P=.75, respectively). CONCLUSIONS: The use of 70% isopropyl alcohol showed no additional benefit over simple mechanical scraping in the removal and prevention of epithelial ingrowth recurrence following LASIK.

2-Propanol↗