1/5. Bilateral microcornea and unilateral macrophthalmia resulting in incorrect intraocular lens selection.A 79-year-old man with symmetrical microcornea and a dense unilateral nuclear sclerotic cataract had cataract extraction by phacoemulsification. The SRK/T formula suggested a 10.0 diopter (D) intraocular lens (IOL) for emmetropia (axial length 26.58 mm). The non-cataract eye required a 25.0 D IOL for emmetropia (axial length 21.51 mm). Biometric measurements were rechecked, and an 18.0 D IOL was implanted (axial length 24.02 mm). The 6 week postoperative refraction of -13.0 2.0 x 25 necessitated IOL exchange (10.0 D). Six weeks postexchange, the refraction was -3.75 2.5 x 30. This illustrates that symmetrical anterior microphthalmos does not always coexist with symmetrical posterior microphthalmos. awareness of the association of symmetrical microcornea and unilateral colobomatous macrophthalmia may aid appropriate IOL selection in future cases.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
2/5. Contact lens fitting difficulties following refractive surgery for high myopia.PURPOSE: To describe the clinical and optical problems encountered in contact lens fitting following refractive surgery for high myopia. methods: Following refractive surgery for high myopia (greater than -10.00 D) we corrected residual refractive errors with contact lenses in the four eyes of two patients. The first patient had undergone bilateral laser in situ keratomileusis (LASIK),with two subsequent LASIK retreatments in the left eye. Ten months later she was fit with rigid gas permeable (RGP) lenses in both eyes. The second patient had undergone a clear lens extraction in the right eye and radial keratotomy followed by photorefractive keratectomy(PRK) in the left eye. She was fit with toric soft lenses six years postoperatively. RESULTS: Final visual acuity obtained with contact lenses was 20/25-20/20 in all eyes. The first patient required significant minus lens power compensation. Furthermore, the RGP lens in the left eye was slightly decentered due to corneal irregularity induced by LASIK. The second patient had regular corneal surfaces and was successfully fit with daily wear toric soft lenses despite the 2.75 D of residual astigmatism in the left eye. CONCLUSIONS: Following refractive surgery for high myopia a proportion of patients will remain undercorrected. In these patients the alterations in corneal architecture that ensue make contact lens fitting more challenging. patients with regular astigmatism may be fitted successfully with toric soft lenses. patients with corneal irregularities should be fit with RGP lenses.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
3/5. Possible role of the vitamin e solubilizer in topical diclofenac on matrix metalloproteinase expression in corneal melting: an analysis of postoperative keratolysis.OBJECTIVE: To analyze tissue matrix metalloproteinase (MMP) expression in three patients who developed postoperative corneal melts after treatment with topical diclofenac sodium 0.1% (Falcon; Fort Worth, TX) ophthalmic solution. DESIGN: Retrospective noncomparative interventional case series with tissue analysis. MAIN OUTCOME MEASURES: Three patients were examined in this study. We report two patients from the same center with acute corneal melts after uncomplicated photorefractive keratectomy (PRK). Prior to these cases, 1500 patients were treated at the Zale Lipshy University Laser Center for Vision with no adverse effects. All 1500 patients were treated with the same postoperative regimen of ciprofloxacin, rimexolone, and suprofen ([Profenal, (CIBA, Duluth, GA]). The next 27 cases were treated postoperatively with ciprofloxacin and rimexolone. However, diclofenac sodium 0.1% was used instead of Profenal. A third case was also discussed. This melt occurred at another center in a postoperative cataract patient who developed cystoid macular edema after cataract extraction with intraocular lens placement. He was initially treated with diclofenac sodium 0.1% (Ciba Vision, Duluth, GA) then with diclofenac sodium 0.1%. He subsequently developed a corneal perforation requiring penetrating keratoplasty. All tissue specimens were examined by light microscopy. Microbiologic cultures and stains were also performed. Immunolocalization and in situ hybridization were performed on all keratoplasty specimens to detect expression and localization of MMPs. All patients had a complete diagnostic evaluation for systemic autoimmune diseases. RESULTS: Postoperatively, all patients developed corneal perforations requiring surgical intervention while being treated with diclofenac sodium 0.1%. Microbiologic cultures and special stains were negative for microorganisms. Induced expression of specific tissue degrading enzymes of the matrix metalloproteinase family was demonstrated within corneal epithelial cells, stromal keratocytes, and at the level of Descemet's membrane. The uniform distribution pattern of expression was not consistent with the localization expected of a repair response, suggesting the involvement of some outside agent. CONCLUSIONS: Whereas MMP expression is a normal component of repair, excessive or inappropriate MMP activity is associated with corneal keratolysis. Our study provides preliminary evidence that topical application of diclofenac sodium 0.1% may be associated with aberrant MMP expression in the cornea.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
4/5. Potential complications of ocular surgery in patients with coexistent keratoconus and fuchs' endothelial dystrophy.PURPOSE: To describe the potential complications of cataract and refractive surgery in patients with fuchs' endothelial dystrophy (FED) and keratoconus. DESIGN: Retrospective case series. PARTICIPANTS: Eight patients with FED and keratoconus in a large university group practice. methods: We reviewed the clinical and topographic findings of 8 patients (15 eyes) with FED and keratoconus. Clinical examination, corneal topography, specular microscopy were done, and sequential central corneal thickness (CCT) was obtained. Follow-up ranged from 1 month to 6 years. MAIN OUTCOME MEASURES: Findings of keratoconus and FED in preoperative evaluation. RESULTS: Five patients had concomitant cataracts; 3 had refractive errors and sought surgical correction. Cataract surgery was performed on 3 of 5 patients (5 eyes). LASIK was performed on one eye of 3 patients. Of 5 eyes that underwent cataract extraction, 4 had blurry vision after surgery. The interval between the surgical procedure and onset of symptoms ranged from 1 month to 4 years. The causes of decreased vision after cataract surgery were corneal edema and/or corneal ectasia. The CCT readings ranged from 426 to 824 microm. One of 4 symptomatic eyes underwent penetrating keratoplasty. The CCTs of 3 patients (6 eyes) who presented with refractive error ranged from 507 to 565 microm. One eye had undergone an attempted LASIK procedure resulting in a lost cap. corneal topography and specular microscopy showed the coexistence of keratoconus and FED, and the patients were advised against having LASIK surgery. CONCLUSIONS: Corneal thinning caused by keratoconus and concurrent increase in corneal thickness caused by FED may combine to normalize the corneal pachymetry readings; disease severity may be underestimated, which may lead to unexpected postoperative visual outcomes. Routine use of preoperative topography and specular microscopy may help to avert potential surgical complications.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |
5/5. Refractive complications of cataract surgery after radial keratotomy.Four patients underwent cataract extraction with posterior chamber lens implantation several years after radial keratotomy. All four patients experienced an initial hyperopic shift caused by an early postoperative corneal flattening of greater than or equal to 1 diopter. This flattening partially regressed, leaving the patients with a mean of 0.42 diopter of persistent corneal flattening. We found the Binkhorst and the Holladay intraocular lens calculation formulas to be more accurate than the SRK II for these patients. Corneal curvature measured with the keratometer was less accurate for intraocular lens calculations than was a value derived by subtracting the refractive change induced by the radial keratotomy from the patients' keratometric measurements obtained before radial keratotomy.- - - - - - - - - - ranking = 1keywords = extraction (Clic here for more details about this article) |