PURPOSE: To evaluate subfoveal choroidal thickness in patients with central retinal vein occlusion (CRVO) using enhanced depth imaging (EDI) optical coherence tomography (OCT). DESIGN: Retrospective observational study.METHODS: We measured bilateral subfoveal choroidal thickness, averaged for 100 scans, in 36 patients (mean age, 66 ± 15 years; 26 women and 10 men) with unilateral CRVO by using the EDI modes of the Spectralis OCT system. Twenty-two patients were treated with intravitreal bevacizumab (1.25 mg/0.05 mL), and subfoveal choroidal thickness was measured before and after treatment. Statistical analysis was performed to compare subfoveal choroidal thickness of CRVO and fellow eyes, and subfoveal choroidal thickness before and after intravitreal bevacizumab.RESULTS: Mean subfoveal choroidal thickness measured in 36 eligible eyes of 36 patients was 257.1 ± 83.2 μm, which was significantly greater than that in fellow eyes (222.6 ± 67.8 μm) (P < .01, paired t-test). There was strong correlation between CRVO eyes and fellow eyes (r = .79, P < .01). Mean subfoveal choroidal thickness after intravitreal bevacizumab was 227.7 ± 65.1 μm, which was significantly thinner than that before intravitreal bevacizumab Abstract (MUST be submitted as a separate file) therapy (266.9 ± 79.0 μm) (P < .01, paired t-test).CONCLUSIONS: Subfoveal choroidal thickness of CRVO eyes was significantly greater than that of fellow eyes and significantly decreased after intravitreal bevacizumab treatment. EDI-OCT can be used to evaluate choroidal involvement in CRVO and may assist noninvasive diagnosis and management of this disease.

The dynamic Scheimpflug analyzer provides a method to obtain new biomechanical information on the cornea such as the DA and R hc, and these parameters differed among eyes that had undergone 3 different types of corneal surgery. Abnormalities in these parameters after the different corneal transplantation techniques may indicate larger deviations in the stress-strain reaction of the cornea and more uncertainty in the intraocular pressure measurements than in normal eyes.

Corneal biomechanical features evaluated using the dynamic Scheimpflug analyzer suggest that biomechanical properties in eyes with keratectasia, keratoconus, and LASIK are different from those of normal eyes. Although the biomechanics in eyes with keratectasia differs from that in eyes with LASIK, it is similar to that in eyes with keratoconus.

Purpose: To develop a device that is capable of easily measuring corneal transepithelial electrical resistance (TER) and changes in the corneal barrier function. Methods:We had previously developed an in vivo method for measuring corneal TER using intraocular electrode. This method can be used to precisely measure the decline of the corneal barrier function after instillation of benzalkonium chloride (BAC). In order to lessen the invasiveness of that procedure, we further refined the method for measuring the corneal TER by developing electrodes that could be placed on the cornea and in the conjunctival sac instead of inserting them into the anterior chamber. TER was then calculated by subtracting the electrical resistance, which lacked the corneal epithelial input, from the whole electrical resistance that was measured between the electrodes. Slit lamp examination and scanning electron microscopy (SEM) were used to determine safety of the new device. Corneal TER changes after exposure to 0.02% BAC were determined using the new device as well as SEM and transmission electron microscopy (TEM).Results: Slit lamp examination before and after exposure of rabbits' corneas to the sensor confirmed safety of the device. SEM examination revealed no difference of the corneal epithelium which exposed to the new device with normal corneas. SEM and 3 TEM pictures revealed damaged microvilli and tight junctions after instillation of 0.02% BAC. TER change after treatment with 0.02%BAC was similar to those determined by the established anterior chamber method. Conclusion:We succeeded to develop a less invasive device for corneal TER measurement in vivo in animals. This new device may be applicable in the future for clinical use in humans.