Comparison of Intraocular Pressures Measured by the Corvis ST and Other Tonometers in Normal Eyes

PURPOSE@#We compared the intraocular pressures (IOPs) measured by the Corvis ST (CST), Goldmann applanation tonometer (GAT), and Rebound tonometer (RBT) and correlated the measured IOPs with the corneal center thickness (CCT).@*METHODS@#The IOPs were measured in 34 eyes of 34 normal subjects using the CST, GAT, and RBT by independent examiners. Comparisons between the IOPs measured by the CST and other tonometers were made using paired t-tests and Bland-Altman plots and Pearson's correlation coefficient was used to correlate the measured IOPs with the CCTs.@*RESULTS@#The IOP measured by the CST (C-IOP; 14.57 ± 2.37 mmHg) was significantly higher than that measured by the GAT(13.56 ± 2.25 mmHg) and RBT (13.57 ± 3.26 mmHg) (p 0.50). In analyzing the correlation with CCT, RBT-IOP (R =0.34; p = 0.705) showed a lower correlation than the GAT-IOP (R = 0.49; p < 0.01) and C-IOP (R = 0.48; p < 0.01). The C-bIOP showed no correlation with the CCT (p = 0.74).@*CONCLUSIONS@#The IOP measurements using the C-IOP were significantly higher than the RBT-IOP and GAT-IOP but the C-bIOP showed no difference from the RBT-IOP and GAT-IOP. C-IOP, RBT-IOP, and GAT-IOP were significantly correlated with corneal thickness, but there was no correlation between CCT and C-bIOP. C-bIOP may therefore be considered clinically useful.

A Case of Inferior Rectus Muscle Enlargement after Taking Sildenafil Citrate

PURPOSE: Sildenafil citrate was developed to treat angina, but was found to also inhibit PDE in the corpus callosum and is now widely used to treat impotence. We report a case of enlargement of the inferior rectus muscle after sildenafil citrate ingestion. CASE SUMMARY: A 58-year-old male presented with binocular diplopia which started 2 weeks prior. He had no underlying disease. The patient had taken sildenafil citrate on 3 different occasions 2 weeks prior, and 2 days after his first ingestion, his right conjunctiva was injected and binocular diplopia started. On the first visit, he showed 16 PD hypotropia of the right eye with limitation of motion at upgaze. The MRI scan showed enlargement and enhancement of the inferior rectus muscle, and 50 mg of prednisone was prescribed. The amount of hypotropia decreased to 8 PD 2 weeks later. CONCLUSIONS: Enlargement of extraocular muscle caused by sildenafil citrate ingestion has not been reported in Korea, and related mechanisms are yet to be researched. Additional case reports and research are necessary in the future.

Corneal Endothelial Changes after Laser-Assisted Subepithelial Keratomileusis

PURPOSE: In order to investigate the safety of laser-assisted subepithelial keratomileusis (LASEK), corneal endothelial cells before and after the LASEK procedure were evaluated. METHODS: Thirty-six patients (72 eyes) who underwent LASEK between June 2010 and May 2011 were included in the present study. Parameters included corneal endothelial cell density (CD), coefficient of variation of the cell area (CV), and percentage of hexagonal cells (6A) which were all obtained by a specular microscope (Noncon ROBO sp 8000, Konan, Japan) before and 3, 6, and 12 months after LASEK. RESULTS: Preoperative CD was 2952 +/- 352 cells/mm2, and postoperative CD did not significantly change at 3, 6, and 12 months. Preoperative CV and 6A and postoperative CV and 6A at 12 months were not significantly different. Furthermore, correlation between change in corneal endothelial cell and degree of myopia correction was not statistically significant. CONCLUSIONS: LASEK appears to be a safe procedure for corneal endothelial cells over an extended period.