Corneal Biomechanical Properties and Thickness in Primary Congenital Glaucoma and Normal Eyes: A Comparative Study

The correct estimation of Intraocular Pressure (IOP) is the most important factor in the management of various types of glaucoma. Primary congenital glaucoma is a type of glaucoma that can cause blindness in the absence of control of the IOP. In this retrospective observational study, 95 eyes, including 48 healthy eyes and 47 eyes with Primary Congenital Glaucomatous (PCG) were studied. Two groups were matched for age, gender, and Goldman Applanation Tonometry (GIOP). Corneal Hysteresis (CH), Corneal Resistance Factor (CRF), and Goldman intraocular pressure were measured by ORA (IOPg), and corneal compensated Intraocular Pressure (IOPcc) was measured for each patient using the Ocular Response Analyzer (ORA). Central Corneal Thickness (CCT) was measured by ultrasonic pachymetry. For each patient, one eye was selected randomly. Student’s t-test and analytical regression were used for statistical analysis. The two groups were matched for age (P = 0.34), gender (P = 0.47), and GIOP (P = 0.17). Corneal hysteresis and CRF were significantly lower in PCG than in normal eyes (P < 0.0001), yet CCT was significantly thicker in PCG than normal eyes (P < 0.0001). The regression equation on the effect of CH, CRF, and CCT on GIOP in the PCG group showed that CH and CRF (P-value = 0.001 and P-value<0.0001) also had a significant effect yet CCT did not (P-value = 0.691). A significant decrease in CH and CRF was found in the PCG group compared to the normal controls. In the PCG group, the CCT was greater than normal. These results showed the usefulness of biomechanical properties (CH, CRF) in order to interpret IOP measurements. Furthermore, GIOP measurement may not be confined to consideration of CCT alone. A low CH and CRF value could be responsible for under-estimation of GIOP in the PCG group, in comparison to the normal controls

Inferior Spear-like Lens Opacity as a Sign of Keratoconus

Purpose: To report 21 cases of typical inferior feather-shape lens opacity associated with keratoconus. Methods: In this cross-sectional study, we evaluated the association of keratoconus with inferior feather-shape lens opacity in refractive surgery candidates. Visual acuity, demographic, refractive, and topographic characteristics of 26 eyes of 21 patients with inferior feather-shape lens opacity were evaluated in detail. Pedigree analysis was also performed to assess possible inheritance. Results: Overall, 2122 out of 33,368 cases (6.4%) without lens opacity had keratoconus, while 20 out of 21 patients (95.2%) with peculiar lens opacity had definite keratoconus (P < 0.001). Lens opacity was bilateral in 5 cases (24%), and keratoconus was bilateral in all 20 patients with lens opacity. Nine eyes out of thirty-six with a complete data record (25%) had severe keratoconus and underwent deep lamellar keratoplasty, while 11 (31%) had forme fruste keratoconus. Pedigrees were drawn for eight patients, most families of whom suggested an X-linked recessive inheritance. Conclusion: The present study was the first to investigate patients with a peculiar inferior feather-shape lens opacity accompanied by bilateral keratoconus, which was observed in 95% of the patients. This finding should raise awareness as to the possibility of diagnosing keratoconus in the eyes of the patients with these characteristics

Corneal Biomechanical Properties and Thickness in Primary Congenital Glaucoma and Normal Eyes: A Comparative Study

The correct estimation of Intraocular Pressure (IOP) is the most important factor in the management of various types of glaucoma. Primary congenital glaucoma is a type of glaucoma that can cause blindness in the absence of control of the IOP. In this retrospective observational study, 95 eyes, including 48 healthy eyes and 47 eyes with Primary Congenital Glaucomatous (PCG) were studied. Two groups were matched for age, gender, and Goldman Applanation Tonometry (GIOP). Corneal Hysteresis (CH), Corneal Resistance Factor (CRF), and Goldman intraocular pressure were measured by ORA (IOPg), and corneal compensated Intraocular Pressure (IOPcc) was measured for each patient using the Ocular Response Analyzer (ORA). Central Corneal Thickness (CCT) was measured by ultrasonic pachymetry. For each patient, one eye was selected randomly. Student’s t-test and analytical regression were used for statistical analysis. The two groups were matched for age (P = 0.34), gender (P = 0.47), and GIOP (P = 0.17). Corneal hysteresis and CRF were significantly lower in PCG than in normal eyes (P < 0.0001), yet CCT was significantly thicker in PCG than normal eyes (P < 0.0001). The regression equation on the effect of CH, CRF, and CCT on GIOP in the PCG group showed that CH and CRF (P-value = 0.001 and P-value<0.0001) also had a significant effect yet CCT did not (P-value = 0.691). A significant decrease in CH and CRF was found in the PCG group compared to the normal controls. In the PCG group, the CCT was greater than normal. These results showed the usefulness of biomechanical properties (CH, CRF) in order to interpret IOP measurements. Furthermore, GIOP measurement may not be confined to consideration of CCT alone. A low CH and CRF value could be responsible for under-estimation of GIOP in the PCG group, in comparison to the normal controls

Corneal Parameters in Healthy Subjects Assessed by Corvis ST

Purpose: To evaluate corneal biomechanics using Corvis ST in healthy eyes from Iranian keratorefractive surgery candidates. Methods: In this prospective consecutive observational case series, the intraocular pressure (IOP), central corneal thickness (CCT), and biomechanical properties of 1,304 eyes from 652 patients were evaluated using Corvis ST. Keratometric readings and manifest refraction were also recorded. Results: The mean (±SD) age of participants was 28 ± 5 years, and 31.7% were male. The mean spherical equivalent refraction was –3.50 ± 1.57 diopters (D), the mean IOP was 16.8 ± 2.9 mmHg, and the mean CCT was 531 ± 31 μm for the right eye. The respective means (±SD) corneal biomechanical parameters of the right eye were as follows: first applanation time: 7.36 ± 0.39 milliseconds (ms); first applanation length: 1.82 ± 0.22 mm; velocity in: 0.12 ± 0.04 m/s; second applanation time: 20.13 ± 0.48 ms; second applanation length: 1.34 ± 0.55 mm; velocity out: –0.67 ± 0.17 m/s; total time: 16.84 ± 0.64 ms; deformation amplitude: 1.05 ± 0.10 mm; peak distance: 4.60 ± 1.01 mm; and concave radius of curvature: 7.35 ± 1.39 mm. In the linear regression analysis, IOP exhibited a statistically significant association with the first and second applanation times, total time, velocity in, peak distance, deformation amplitude, and concave radius of curvature. Conclusion: Our study results can be used as a reference for the interpretation of Corvis ST parameters in healthy refractive surgery candidates in the Iranian population. Our results confirmed that IOP is a major determinant of Corvis parameters

Influence of Corneal Biomechanical Properties on Intraocular Pressure Differences Between a non-contact ORA Tonometer and the Goldmann Applanation Tonometer in primary congenital glacomatous children

This study aimed at evaluating the effect of corneal properties on the difference between IOP measured with non-contact tonometer (IOPcc)and contact goldman applantation tonometer(GIOP) in children with primary congenital glaucoma(PCG) .In current study The influence of central corneal thickness (CCT), keratometry(Km),equicalent sphere of refractive error (ES) and Ocular Response Analyzer (Reichert) measurements of corneal viscoelasticity [corneal hysteresis (CH) and corneal resistance factor (CRF)] on IOP differences between tonometers was evaluated in children with PCG . The CH was calculated to be the best predictor of the differences in IOP readings between tonometers (r2=0.46; P< 0.0001 . CRF,CCT,Es and Keratometry performed very poorly as lone predictor of IOP differences. In a multiple regression model CH and CRF together accounted for 84% (r2=0.84; P< 0.0001) of the variance in IOP reading differences between tonometers. Corneal viscoelastic properties (CH)induced by either contact or noncontact tonometers was calculated to be the most determinant factor in influencing IOP differences(IOPcc-GIOP)

Hydatidosis of the Pelvic Cavity: A Big Masquerade

We report and discuss a case of primary hydatidosis of the pelvic cavity in a woman who presented with severe weight loss and abdominal pain. This unusual presentation was initially considered as a tumor process until surgical exploration and microscopic studies confirmed the diagnosis. The gynecologists should be aware of possibility of primary hydatid cyst of the pelvic cavity and should be considered in the differential diagnosis of cystic pelvic masses, especially in areas where the disease is endemic

Therapeutic Effect of Intrastromal Voriconazole, Topical Voriconazole, and Topical Natamycin on Fusarium

Purpose. Evaluating the therapeutic effect of topical and intrastromal voriconazole and topical natamycin on Fusarium keratitis. Methods. 24 rabbits were selected. The stroma of their corneas was inoculated with suspension of Fusarium solani species complex. Seven days after injection they were divided into 4 groups randomly: the first group was treated with topical voriconazole (TV) 1% for one week, the second one with one-time intrastromal injection of voriconazole (ISV) 50 microgram/0.1 mL, and the third group with topical gel of natamycin (TN) for one week, and the last one did not receive any antifungal treatment. Finally the eyes were enucleated and sclerocorneal buttons were sent for histological and microbiological examinations. Results. After treatment the ISV group and TN group showed significantly lower clinical score and colony forming units than the control group (P=0.040 and P=0.026, resp.), but there was statistically no significant difference between control and TV groups (P=0.249) or between ISV and TN groups (P=0.665). In pathological evaluation, fewer chronic inflammations were reported in 2 of the 3 buttons from TV group and 3 of the 3 buttons from ISV and TN groups in comparison with the control group. Conclusion. Intrastromal injection of voriconazole seems to be effective in treatment of Fusarium keratitis as much as topical natamycin and these are more effective than topical voriconazole