Postoperative opacification of polymethylmethacrylateintraocular lens.

Background: Opacification of ophthalmic devices has been previously reported in silicone scleral buckle, Molteno implant, and intraocular lens opacification. However, there is no report on polymethyl methacrylate (PMMA) intraocular lens (IOL) calcification. Objective: Report the clinical feature, histopathologic and spectrophotometer analysis of opacified three-piece PMMA IOL. Method: A 60-year-old diabetic patient reported decreased visual acuity in her right eye, which had undergone phacoemulsification with PMMA IOL implantation. The ophthalmic examination revealed a white homogeneous opacification of posterior surface of the IOL. The explanted IOL was analyzed using scanning electron microscopy, energy dispersive spectroscopy, and alizarin red staining. Results: The scanning electron microscope analysis showed granular deposits on posterior surface of the IOL. Using energy dispersive spectroscopy analysis, calcium and phosphate peaks were revealed, which was confirmed by positive for alizarin red staining. Conclusion: This case report provided evidence of PMMA IOL calcification caused by calcium and phosphate deposits. The possible etiologies were extrinsic and/or intrinsic factors.

Single dose of 1% tropicamide and 10% phenylephrine for pupil dilation.

OBJECTIVE: To compare the efficacy of pupil dilation between a single dose and three doses of 1% tropicamide and 10% phenylephrine for binocular indirect ophthalmoscopy. MATERIAL AND METHOD: A prospective randomized double-blind clinical controlled trial was conducted. All patients underwent the binocular indirect ophthalmoscopy and met the inclusion criteria were randomized into two groups using block randomization. Group A received a single dose of 1% tropicamide and 10% phenylephrine eye drops, and Group B received three doses of the same drugs. The primary outcome was the horizontal pupil diameter measured by slit-lamp biomicroscope (Haag-Streit model 900) before and at 10, 15, 20, 25 and 30 minutes after eye drop instillation. The clinical equivalence of the efficacy of pupil dilation between the two groups was defined as the difference of less than or equal to 1 mm (-1 mm to + 1 mm). RESULTS: Eighty patients (160 eyes) were randomized into 40 patients (80 eyes) in group A and 40 patients (80 eyes) in group B. The mean pupil sizes at baseline of group A were 3.51 +/- 0.63 mm in the right eye and 3.39 +/- 0.67 mm in the left eye. Those in group B were 3.61 +/- 0.67 mm in the right eye and 3.66 +/- 0.72 mm in the left eye. The mean pupil diameters at 30 minutes of group A were 7.34 +/- 0.51 mm in the right eye and 7.41 +/- 0.56 mm in the left eye, whereas those of group B were 7.49 +/- 0.45 mm in the right eye and 7.51 +/- 0.40 mm in the left eye. The mean difference of the pupil size between the two groups was 0.15 mm (p = 0.175) in the right eye and 0.l0 mm (p = 0.362) in the left eye. The 95% confidence intervals of the difference in pupil size were -0.36 to 0.07 mm in the right eye and -0.32 to 0.12 mm in the left eye. CONCLUSION: The 95% confidence interval of the difference in pupil size lay entirely within the range of equivalence. The single dose of 1% tropicamide and 10% phenylephrine was clinically equivalent to the three doses of the same drugs.

Translimbal fixation of posterior chamber lenses.

OBJECTIVES: To evaluate the result of a surgical technique to insert and secure a standard posterior chamber lens through a simple limbal incision in eyes that had no capsular support or whose capsule was inadvertently ruptured during extracapsular cataract extraction. MATERIAL AND METHOD: Retrospective review of the medical records of patients who underwent translimbal fixation of posterior chamber lenses according to age, gender, preoperative visual acuity, postoperative visual acuity, follow-up period and any complications, especially those that may be related to the surgical technique. RESULTS: Twelve patients were recruited in the present study. The patents' age ranged from 31 to 77 years, with a mean of 62.58 years. There were 9 male and 3 female patients. The preoperative visual acuity ranged from hand motion to counting fingers, and the postoperative visual acuity ranged from 6/6 to 6/24 except one patient who had postoperative visual acuity of counting fingers due to a pre-existing macular hole. The length of follow-up period ranged from 3 to 12 months, with a mean of 6.17 months. There was no clinically significant lens-related complication. CONCLUSION: This simple surgical technique controls the location of the needle entry and exit to decrease the risk of bleeding and increase the chance of ciliary sulcus placement. An inferior groove was made to bury the suture knot and was sutured closed to prevent the knot erosion through the conjunctiva.