Normal Retinal Nerve Fiber Layer Thickness in the Peripapillary Region of Koreans Measured by Scanning Laser Polarimeter

PURPOSE: To measure normal retinal nerve fiber layer thickness (RNFLT) in the peripapillary region of Koreans using a scanning laser polarimeter, the nerve fiber analyzer (GDx VCC). METHODS: Two hundred ninety-nine eyes of 299 healthy subjects (156 men, 143 women) were recruited for this study. No subject had diabetes mellitus, hypertension, or any other neurologic disorders. All subjects were normal at ophthalmologic examination, which was assessed by slit-lamp biomicroscopy using a 90-diopter lens, Goldmann applanation tonometry, and Humphrey visual field analysis. Using the GDx VCC, we analyzed the mean value of each parameter in GDx VCC (average at global, superior, inferior, superior maximum and inferior maximum) and evaluated the difference between men and women and each decade of age. RESULTS: Mean RNFLT parameters in GDx VCC were global 56.42 +/- 6.84 micrometer, superior 70.51 +/- 8.70 micrometer, inferior 67.55 +/- 9.04 micrometer, superior maximum 83.52 +/- 12.38 micrometer, and inferior maximum 82.64 +/- 12.70 micrometer. The parameters which showed a difference between men and women were superior average and superior and inferior maximum average RNFLT. The superior RNFLT was thicker than the inferior ones. RNFLT was not statistically different in each decade of age. CONCLUSIONS: We can make good use of the normal parameters of GDx VCC in Koreans for early diagnosis and follow-up of glaucoma.

Anterior Lens Capsule Abnormalities in Alport Syndrome

Alport syndrome is a hereditary, progressive disease characterized by progressive nephritis, sensorineural deafness, and ocular abnormalities, including anterior lenticonus. The ultrastructure of the lens capsule abnormalities in Alport syndrome is reported. Four anterior lens capsules from 31-year-old patient and 26-year-old patient with lenticonus who were affected by the Alport syndrome were obtained at capsulectomy. And all four anterior lens capsules were examined by transmission electron microscopy. The histopathologic findings showed that the thickness of the anterior lens capsules was decreased (4~13 micrometer) and that there were many vascular dehiscences localized at the inner part of the lens capsule. There were large numbers of capsular dehiscences containing fibrillar materials and vacuoles. The anterior capsules were clearly fragile in this disease, forming the basis for the progressive lenticonus and anterior polar cataract.

The Reproducibility and Accuracy of Biometry Parameter Measurement from IOL Master(R)

PURPOSE: To evaluate the reproducibility and accuracy of axial length and anterior chamber depth measurements from IOL Master(R). METHODS: The axial length and anterior chamber depth measurements in 30 eyes with normal crystalline lens, 30 eyes with cataract and 30 pseudophakic eyes were measured by two practitioners using IOL Master(R) followed by A-scan and Orbscan II. The reproducibility of IOL Master(R) was analyzed by comparing the results from the first and second practitioners. To evaluate the accuracy of IOL Master(R), the axial length was compared to A-scan and the anterior chamber depth was compared to A-scan and Orbscan II. RESULTS: The difference between the axial length and anterior chamber depth measurements from the two practitioners using IOL Master(R) were not statistically significant (p>0.05). The axial length of measurement from IOL Master(R) was 0.16 mm, 0.18 mm, and 0.96 mm longer than that from A-scan, in the normal, cataract and pseudophakic groups, respectively. In addition, the anterior chamber depth measurement from IOL Master(R) was significantly deeper than that from A-scan and Orbscan II (p<0.05). CONCLUSIONS: There was good reproducibility and accuracy of axial length and anterior chamber depth measurements from IOL Master(R). However, some patients who had media opacity were not measured using IOL Master(R). It is a noncontact method, which provides an alternative to A-scan.