Assessment of Corneal Densitometry in Rheumatoid Arthritis Patients.

OBJECTIVES: To evaluate corneal densitometry and anterior segment parameters of rheumatoid arthritis (RA) patients and compare these results with those of age-matched healthy control subjects. MATERIALS AND METHODS: Anterior segment parameters and corneal densitometry of patients with RA and healthy control subjects were assessed by Scheimpflug corneal topography. For densitometry analysis, the 12-mm diameter area of the cornea was subdivided into four concentric radial zones and anterior, central, and posterior layers based on corneal depth. Right eyes of subjects were used for statistical analysis. RESULTS: Twenty-three consecutive patients with RA and 22 healthy control subjects were included in the study. There was no significant difference with regard to age (p=0.487) or gender (p=0.514). When anterior segment parameters of both groups were compared, no significant difference was found (p>0.05). Total corneal densitometry values were statistically higher in the RA group (p=0.030). In addition, when subdivisions of the cornea were evaluated, higher densitometry values were found in the RA group in 0-2 and 2-6 mm radial zones both in the anterior and total depth (p=0.001, p=0.003 for the 0-2 mm zone and p=0.002, p=0.009 for the 2-6 mm zone). Corneal densitometry measurement was not correlated with central corneal thickness or simulated keratometry value in RA patients or healthy control subjects. CONCLUSION: The corneal densitometry values were higher in RA patients when compared to healthy control subjects, even if they had clinically clear corneas. Corneal densitometry as an objective measure of corneal clarity warrants further studies in order to ascertain its clinical relevance in RA patients.

Quantitative assessment of corneal clarity in keratoconus: a case control study of corneal densitometry.

PURPOSE: To evaluate corneal clarity quantitatively by corneal densitometry measurement in treatment-naive keratoconus patients and to compare these results with those of healthy control subjects. METHODS: Corneal densitometry measurement of consecutive treatment-naive keratoconus patients and healthy control subjects was performed by Scheimpflug corneal topography (Pentacam®HR). Corneal densitometry measurements were expressed in gray scale unit (GSU) and the data from the right eyes of subjects were used for statistical analysis. RESULTS: A total of 102 subjects (51 patients with keratoconus [27 male, 24 female] and 51 healthy control subjects [24 male, 27 female]) were included in the study. There was no statistically significant difference with regard to the mean age (p = 0.910) or distribution of sex (p = 0.552) between the groups. There were significant differences in corneal densitometry values of the groups in central 2 mm (17.95 ± 0.33 GSU in keratoconus and 16.43 ± 0.24 GSU in controls, p<0.001) and in annulus of 2 to 6 mm in diameter (15.88 ± 0.26 GSU in keratoconus and 15.02 ± 0.22 GSU in controls, p = 0.015). When considering the measurements in different depths, the anterior layer displayed the highest densitometry value compared to that of both the central and posterior layers. Corneal densitometry of anterior 0-2 mm was positively correlated with simulated K value (r = 0.446, p = 0.001), whereas it was negatively correlated with central corneal thickness (r = -0.361, p = 0.016) in keratoconus patients. CONCLUSIONS: Treatment-naive keratoconus patients have significantly higher corneal densitometry values in central cornea when compared to healthy control subjects. The clinical relevance should be further studied in detail.

Evaluation of Optical Low Coherence Reflectometry Parameters in Patients with Exfoliation Syndrome.

Purpose. To evaluate optical low coherence reflectometry (OLCR) parameters in patients with exfoliation syndrome (EXS) undergoing cataract surgery. Methods. Forty-seven eyes of 47 patients with EXS (Group 1), and 55 eyes of 55 healthy subjects (Group 2) were included in the study. Anterior chamber depth (ACD), lens thickness (LT), axial length (AL), central corneal thickness (CCT), horizontal corneal length (HCL), and pupil diameter (PD) parameters were measured by OLCR (Lenstar LS 900, Haag-Streit) and compared between groups. Shapiro-Wilk test and Mann Whitney U tests were used for statistical analyses. Results. The mean ACD, HCL, and PD values were significantly lower in EXS group than in healthy subjects (P = 0.01, P = 0.04, and P < 0.001, resp.). The mean LT was significantly higher in EXS group than in healthy subjects (P = 0.007). There was no significant difference between groups in means of AXL and CCT. Conclusions. According to OLCR measures, eyes with EXS have shallower ACD, smaller PD, thicker LT, shorter HCL, and no significantly different CCT levels.

Decreased retinal nerve fiber layer thickness in patients with congenital isolated growth hormone deficiency.

PURPOSE: To evaluate the optic disc topography parameters of children with congenital isolated growth hormone deficiency (GHD) using the Heidelberg retina tomograph (HRT) in a controlled study. METHODS: This prospective study included 32 eyes of 32 patients with congenital isolated GHD and 36 eyes of 36 healthy subjects. The topographic optic disc parameters (mean cup volume, rim volume, cup area, disc area, rim area, mean cup-to-disc ratio and cup depth, retinal nerve fiber layer thickness [RNFL]) were imaged in all subjects with HRT-III (software 3.01 a-M). Pearson correlation analysis was used to investigate the correlation between right and left eyes regarding the optic disc parameters. Differences between the 2 groups were evaluated by independent t test, Mann-Whitney U test, and chi-square test. RESULTS: The mean RNFL thickness in children with congenital isolated GHD was found to be statistically significantly thinner than in healthy subjects (p<0.05). However, no statistically significant differences were found between the mean cup volume, rim volume, cup area, disc area, rim area, mean cup-to-disc ratio and cup depth, and mean sectorial RNFL thickness (p>0.05). CONCLUSIONS: The results suggest that congenital GHD may lead to thinner RNFL thickness when compared with healthy subjects. This indicates that GH has an important role in the development of the neural retina.