Plateletcrit in Ocular Pseudoexfoliation Syndrome.

PURPOSE: The aim of this study was to compare all platelet markers, especially plateletcrit (PCT, total platelet mass), in patients with and without ocular pseudoexfoliation (PEX) syndrome. METHODS: One hundred six patients with ocular PEX syndrome (study group) and 106 individuals without ocular PEX syndrome (control group) were enrolled in this retrospective case-control study. The biochemical/hematological laboratory results of both the study and control groups were analyzed by a clinician blinded to the group assignments. The main outcome measures were the PCT, platelet count (PLT), mean platelet volume (MPV), and platelet distribution width (PDW). RESULTS: The mean PCT in the study and control groups were 0.206%±0.520% and 0.171%±0.410%, respectively (P<0.001), and the mean PDW in the study and control groups were 16.12%±1.21% and 14.68%±1.40%, respectively (P<0.001). There were no differences in the MPV or mean PLT (P=0.138 and P=0.055, respectively). The PCT cutoff value was 0.180 (area under the receiver operating characteristics curve, 0.706; P<0.001; 65% sensitivity; 74% specificity). CONCLUSIONS: The PCT and PDW were significantly higher in patients with than without ocular PEX syndrome. These increased parameters may cause microvascular blood flow resistance and the heightened inflammatory response caused by excessive platelet activity, as with other cardiovascular diseases, and may also decrease aqueous humor outflow in ocular PEX syndrome.

A comparison of corneal biomechanical properties in patients with psoriasis and healthy subjects.

OBJECTIVE: To evaluate the differences in corneal biomechanical properties between healthy subjects and patients with psoriasis using the ocular response analyzer (ORA). METHODS: Fifty-nine eyes of 59 psoriasis patients and 66 healthy individuals were included in the study. Corneal biomechanical parameters were obtained using ORA. Ultrasound pachymetry was used to measure central corneal thickness (CCT). The main parameters assessed were corneal hysteresis (CH), corneal resistance factor (CRF), Goldmann-correlated intraocular pressure (IOPg) measurement and corneal-compensated IOP (IOPcc) through ORA. The dry eye evaluation was performed with tear break-up time (TBUT) and Shirmer test. RESULTS: The mean CH values in psoriasis and healthy subject eyes were 10.75±2.9 mm Hg, 11.97±3.6 mm Hg, respectively (P=0.047). The mean CRF values were 10.14±3.1 mm Hg and 11.61±3.3 mm Hg, respectively (P=0.012). The mean CCT were 539.1±36 µm and 536.3±28 µm, respectively (P=0.643). Mean TBUT values were 8.2±2.9 sec in psoriasis group and 10.4±3.6 sec in healthy subjects (P<0.001). Shirmer test values were less (8.9±3.8 mm/5 min) in psoriasis than in healthy subjects (13.1±3.6 mm) (P<0.001). CONCLUSIONS: Psoriasis can influence the corneal biomechanical properties. Patients with psoriasis had lower CH and CRF, but higher IOPg and IOPcc values than healthy controls. These corneal biomechanical changes should be considered when determining IOP values.