Comparison of Measured Intraocular Pressure Change According to the Methods of Corneal Refractive Surgery

PURPOSE: To evaluate differences in intraocular pressure change after three different methods of corneal refractive surgery. METHODS: The medical records of 296 eyes of 150 patients who underwent corneal refractive surgery were reviewed. Spherical equivalent, central corneal thickness (CCT), and intraocular pressure before surgery, and one month, three months and six months after surgery were analyzed. RESULTS: The patients included those having undergone laser-assisted in situ keratomileusis (LASIK; 96 eyes), IntraLASIK (98 eyes), laser assisted sub-epithelial keratomileusis (LASEK; 102 eyes). Post operative intraocular pressure in ablated corneal depth and in CCT showed a meaningful correlation. Intraocular pressure decreased significantly after refractive surgery; however, there were no differences among the three groups. CONCLUSIONS: Post operative intraocular pressure after corneal refractive surgery is influenced by CCT. There were no differences in intraocular pressure change among the three groups.

Comparison of Mitomycin C Trabeculectomy and Ahmed Valve Implant Surgery for Neovascular Glaucoma

PURPOSE: To compare the results of mitomycin C trabeculectomy and Ahmed valve implant surgery for neovascular glaucoma (NVG). METHODS: We reviewed the medical records of 58 patients (66 eyes) with NVG who had undergone mitomycin C trabeculectomy or Ahmed valve implant surgery in the previous 5 years. Trabeculectomy (A group) was performed in 27 eyes of 24 patients and valve implant surgery (B group) in 39 eyes of 34 patients. Intraocular pressure (IOP), visual acuity, complications and the rate of surgical success of the two groups were compared. IOP under 21 mmHg without medication was considered as complete success (CS), under 21 mmHg with medication as qualified success (QS), and IOP over 22 mmHg despite medication as failure (F). RESULTS: IOP at postoperative 2 months was lower in the trabeculectomy group than in the drainage implant surgery group (16.4 +/- 11.3 mmHg, 20.9 +/- 8.7 mmHg, P=.087), but at 12 months, there was no statistically significant difference (18.4 +/- 11.5 mmHg, 17.0 +/- 6.4 mmHg, P=.608). Visual acuity also showed no significant difference. The respective rate of success between A and B groups was 66.7% and 38.5% (CS), 25.9% and 33.3% (QS), and 7.4% and 28.2% (F), at postoperative 2 months, and 47.8% and 42.3% (CS), 30.4% and 46.2% (QS), and 21.7% and 11.5% (F), at 12 months. The most common postoperative complication was hyphema in both groups, while other complications were shallow anterior chamber, valve problems, etc. CONCLUSIONS: The type of surgery had no significant effect on the success rate of neovascular glaucoma treatment at postoperative 12 months.

Histologic Characteristics in the Eyes of DBA/2J Mice according to the Degree of Intraocular Pressure

PURPOSE: We assessed the correlation between ocular abnormalities and the degree of intraocular pressure (IOP) in the DBA/2J (D2) transgenic mice which were proven to have pigmentary dispersion syndrome and developing glaucoma. METHODS: Nine-months-old D2 mice were examined with biomicroscopy under anesthesia and measured for IOP by Tono-Pen, Hematoxylin and eosin staining was performed on the eye sections of the mice to analyze differences between the low-grade IOP group and the high-grade IOP group. RESULTS: Ocular abnormalities including iris pigment loss, iris transillumination, iris stromal atrophy, anterior synechia, thinning of the retina, and ganglion cell loss were found; all of which appeared to be pressure- dependent. CONCLUSIONS: These results corroborate that both IOP and age might be considered for studies using D2 mice, and suggest that D2 mice are a useful glaucoma model to study the mechanisms of retinal ganglion cell death and to evaluate strategies for neuroprotection.

Correlation of sFas Level with Uveitis Severity

PURPOSE: The aim of this study is to determine the soluble Fas (sFas) levels in both sera and aqueous humor in patients with uveitis and compare them to the uveitis severity. METHODS: We measured the sFas levels in both sera and aqueous humor (AH) of patients (n=40) with uveitis and non-uveitis controls (n=27). The patients with uveitis comprised 24 Behcet's disease, 6 panuveitis, 5 anterior uveitis, 2 lens induced uveitis, 1 Vogt-Koyanagi-Harada-disease, 1 sarcoidosis, and 1 retinal vasculitis. The severity of uveitis was determined by the Hogan's grading method (0~4 grade) at the time of sampling. RESULTS:The concentration of aqueous sFas in uveitis patients was significantly higher than that in nonuveitis controls, while there was no difference in the serum concentration of sFas between the two groups. In the paired samples of serum and AH, obtained simultaneously, the aqueous sFas levels were higher than serum Fas levels in patients with uveitis, whereas the non-uveitis controls displayed significantly lower sFas levels in AH than in the serum. The sFas levels in AH or serum were not different between Behcet's uveitis and non-Behcet's uveitis. However, in patients with Behcet's uveitis, circulating sFas strongly correlated with aqueous sFas, which was not so in those with non-Behcet's uveitis. Patients (n=29) with more active (grade> or =2) uveitis had significantly higher levels of aqueous sFas than those (n=11) with less active (grade<2) uveitis. After treatment with steroid and/or immunosuppressive agents, aqueous sFas levels were decreased in parallel with a reduction in the number of inflammatory cells in the anterior chamber. CONCLUSIONS: The levels of sFas were elevated in patients with uveitis and correlated well with uveitis severity.

Clinical Results of UNI(R) Intraocular Lens Implantation

We evaluated the clinical results of 43 patients (47 eyes) who underwent cataract extraction and implantation of domestic posterior chamber intraocular lens manufactured by Universal Optics Co. (UNI(R) IOL) and could be followed up over 6 months. The mean follow-up period was 10.2 months with a range of 6 to 15 months. The results were as follows: 1. The final corrected visual acuity of 0.5 or better was noted in 41 eyes (87.2%). 2. The difference between the calculated postoperative refraction and the actual postoperative refraction was less than +/-1.00 D in 33 eyes (70.2%). 3. The corneal thickness increased 8.2% at postoperative period of 3 days and returned to preoperative level at postoperative period of 4 weeks. 4. The corneal endothelial cell density decreased 11.2% at postoperative period of 4 weeks and 12.8% at postoperative period of 6 months. 5. The early postoperative inflammatory reaction in anterior chamber and deposits on the surface of intraocular lens decreased gradually in the course of postoperative period. 6. The postoperative complications included posterior capsular opacification (7 eyes), fibrinous membrane (3 eyes), and hyphema (2 eyes). The above results showed that the visual outcome and the safety of UNI(R) IOL were favorable.