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We aimed to describe congenital keratoglobus with blue sclera in two siblings with overlapping Marshall/Stickler phenotype. Two sisters (ages four and six) with bilateral high astigmatism were evaluated by slit-lamp microscopy. Corneal topography and pachymetry maps were also obtained. Slit-lamp examination revealed that both corneas were globular in shape with peripheral corneal thinning. Pachymetry maps showed diffuse corneal thinning. Two siblings had in common the features of keratoglobus, blue sclera, atypical face, hearing loss, and hypermobile joints. We tentatively diagnosed the sisters as having an overlapping Marshall-Stickler phenotype based on clinical and radiological findings. Marshall-Stickler syndrome may exist in the differential diagnosis of keratoglobus with blue sclera., Competing Interests: There are no conflicts of interest.

Purpose: To monitor corneal thickness during the corneal collagen cross-linking procedure in corneal ectatic diseases, by using isoosmolar riboflavin solution with 20% dextran and hypoosmolar riboflavin solution without dextran., Methods: The corneal thickness measurements were obtained at 5 different time points: after epithelial removal, after isotonic riboflavin solution application for 30 minutes, after hypotonic riboflavin solution application for 10 minutes, and after 10 and 30 minutes of isotonic riboflavin solution application., Results: A total of 9 eyes of 9 patients with progressive keratoconus (n = 8) and pellucid marginal degeneration (n = 1) were included in this study. After epithelial debridement, the thinnest pachymetric readings were between 331 and 399 μm (average, 376.11 ± 19.88 μm). The thinnest pachymetric measurements decreased significantly after the application of isoosmolar riboflavin solution for 30 minutes (by 55.22 ± 13.40 μm) and increased significantly after hypoosmolar riboflavin application for 10 minutes (by 59.56 ± 29.71 μm) (P < 0.01 for both). This artificial swelling effect was transient, and the thinnest pachymetric readings decreased significantly after 10 and 30 minutes of isoosmolar riboflavin application compared with thickness at the end of hypoosmolar riboflavin application (by 50.22 ± 29.68 μm and 65.11 ± 27.94 μm, respectively) (P < 0.01 for both)., Conclusions: The iatrogenic swelling effect of the hypoosmolar riboflavin solution might be short acting and not durable throughout the UVA application in collagen cross-linking procedure.

Purpose: To evaluate the agreement among three different optical methods in measuring anterior chamber depth (ACD), central corneal thickness (CCT), and pupil diameter., Methods: One hundred eyes of 50 healthy patients (25 men, 25 women) were enrolled in the study. Mean patient age was 25 years (range: 21 to 32 years). Exclusion criteria were history of any intraocular or corneal surgery, contact lens wear, corneal anomalies, and spherical refraction >5.00 diopters (D) or cylindrical refraction >2.00 D. All measurements were done by the same operator under mesopic light conditions and repeated using three different optical methods: Visante optical coherence tomography (OCT) (Carl Zeiss Meditec), Orbscan (Bausch & Lomb), and Pentacam (Oculus Optikgeräte GmbH)., Results: Mean CCT as measured by Visante OCT, Orbscan, and Pentacam was 529+/-30.5 microm, 554+/-32.7 microm, and 552+/-29.3 microm, respectively. Mean ACD values were 2.94+/-0.34 mm, 2.84+/-0.33 mm, and 2.98+/-0.33 mm, respectively. Mean pupil diameter measurements were 4.87+/-1.09 mm, 4.0+/-0.67 mm, and 3.05+/-0.59 mm, respectively. The Visante OCT measured CCT thinner and Orbscan measured ACD shallower than the other two methods. All three methods measured pupil diameters significantly different., Conclusions: This study found some statistically significant but clinically insignificant differences among the optical methods assessed. The differences are small and do not influence decisions for refractive surgery in clinical practice.

Purpose: To evaluate the corneal topographic characteristics of first-degree relatives of patients with keratoconus with corneal topography to determine the incidence of clinical keratoconus and topographic abnormalities., Methods: Between February and August 2006, Orbscan II analysis was done in 144 eyes of 72 cases who were first-degree relatives of patients diagnosed with clinical keratoconus. The findings were compared with preoperative Orbscan analyses of 52 clinically normal individuals who underwent laser in situ keratomileusis surgery and did not develop corneal ectasia in 3 years of follow-up., Results: In 8 of the 72 first-degree relatives of patients with keratoconus, clinical keratoconus was diagnosed by the topographic pattern in Orbscan and clinical examination (group 1). The remaining 64 subjects (group 2) were compared with the control group (group 3). The central corneal thickness was 523.7 +/- 40.4 microm in group 2, whereas it was 546.3 +/- 33.1 microm in group 3 (P < 0.05). The central corneal thickness, thinnest pachymetric reading, posterior elevation value, distance between the greatest anterior/posterior elevation points, and corneal center, posterior best fit sphere (BFS) values, posterior BFS:anterior BFS ratio, and irregularity values were significantly different between group 2 and group 3 (P < 0.05)., Conclusions: The keratoconus incidence was found to be 11% in first-degree relatives of patients with keratoconus as opposed to a reported incidence of keratoconus of 0.05% in the general population. In first-degree relatives of patients with keratoconus who did not have a topographic keratoconus pattern, abnormal corneal topographic values were detected. The asymptomatic relatives of patients with keratoconus should undergo a thorough preoperative analysis for subtle topographic abnormalities before any keratorefractive surgery.

Purpose: : To analyze the differences in corneal topography in keratoconus patients with and without atopy., Methods: : In the Beyoglu Eye Research and Training Hospital Refractive Surgery Department, corneal examination with the Orbscan II device (Bausch & Lomb) was done to all patients between May and June 2004 who were diagnosed as keratoconus with corneal topography findings and who did not have any surgical procedure. The atopy grading was done according to the criteria of the UK Atopy Study Group (1994). Patients were divided into 2 groups according to the presence of atopy. The Orbscan findings of the 2 groups were compared., Results: : Among 70 keratoconus patients, 33 patients had partial or full atopy. Sixty-six eyes of the 33 patients were classified as the atopic group, whereas 74 eyes of the remaining 37 patients were classified as the control group. The mean age of the patients was 27.7 +/- 9.5 years in the atopic group and 26.9 +/- 9.5 years in the control group. The central corneal thickness was 428.5 +/- 37.1 mum in the atopic group and 491.8 +/- 56.3 mum in the control group. There was a statistically significant difference between the mean central and thinnest corneal pachymetric readings, the distance of thinnest point to corneal center, anterior and posterior elevation values, distances of the anterior and posterior elevation to the central cornea, and irregularity indexes in the 2 groups (P < 0.05)., Conclusions: : This study shows that corneal topographic and pachymetric characteristics of keratoconus may be different in atopic eyes from those in nonatopic eyes. Atopic keratoconus patients could possibly be evaluated as a separate entity in keratoconus disease.

Purpose: To compare visual and refractive results, contrast sensitivity, and tear stability after laser in situ keratomileusis (LASIK) in one eye and laser epithelial keratomileusis (LASEK) in the fellow eye for low myopia., Methods: Patients diagnosed with low myopia, with a maximum difference of 1 D between their two eyes, were randomly assigned to receive LASEK on one eye and LASIK on the other eye. A total of 64 eyes of 32 patients with a mean age of 26.83 +/- 5.33 years were included in the study. Preoperative myopia ranged from -1.00 to -6.00 D. Follow-up was 6 to 12 months. Uncorrected (UCVA) and best spectacle-corrected visual acuity (BSCVA), Schirmer test results, tear break-up time, corneal asphericity, corneal uniformity index, predicted corneal acuity, and contrast sensitivity values were compared with preoperative values. A Wilcoxon test was used for statistical comparisons and a P-value less than .05 was considered significant., Results: At 6 months after surgery, there was no statistically significant difference in UCVA, BSCVA, spherical and cylindrical refractive error, Schirmer test, or tear break-up time between groups. Contrast sensitivity values in the LASIK eyes were lower in comparison to preoperative values, but there was no change in the LASEK group., Conclusions: Based on 6-month results, LASEK for low myopia was safe and effective with predictable results, offered early refractive stability, and may be considered an alternative for LASIK.