We report a method for computer enhancement of color vision tests. In our graphics system 256 colors are selected from a much larger range and displayed on a screen divided into 768 x 288 pixels. Eight-bit digital-to-analogue converters drive a high quality monitor with separate inputs to the red, green, and blue amplifiers and calibrated gun chromaticities. The graphics are controlled by a PASCAL program written for a personal computer, which calculates the values of the red, green, and blue signals and specifies them in Commité Internationale d'Eclairage X, Y, and Z fundamentals, so changes in chrominance occur without changes in luminance. The system for measuring color contrast thresholds with gratings is more than adequate in normal observers. In patients with mild retinal damage in whom other tests of visual function are normal, this method of testing color vision shows specific increases in contrast thresholds along tritan color-confusion lines. By the time the Hardy-Rand-Rittler and Farnsworth-Munsell 100-hue tests disclose abnormalities, gross defects in color contrast threshold can be seen with our system.

Purpose To determine whether altered eating habits and periods, especially the pre-dawn meal, during Ramadan fasting have any significant effect on intraocular pressure (IOP), tear secretion, corneal and anterior chamber parameters. Methods IOP, basal tear secretion (BTS), reflex tear secretion (RTS), and Pentacam measurements of 31 healthy volunteers were performed at 0800 and 1600 hours during Ramadan fasting and 1 month later during non-fasting period. Results Comparison of measurements between fasting and non-fasting periods at 0800 hours revealed significantly higher values for IOP (P ¼ 0.005), RTS (P ¼ 0.006), and BTS (P ¼ 0.014) during fasting. Conversely at 1600 hours, IOP was significantly lower during fasting (P ¼ 0.013) and no statistically significant difference was noted for RTS and BTS. IOP showed a diurnal variation of 2.45 mmHg (Po0.001) and BTS showed a 3.06 mm decrease (P ¼ 0.04) during the fasting period. No significant differences could be found in the corneal and anterior chamber parameters during fasting and non-fasting periods. Conclusions Our results revealed that fluid loading at the pre-dawn meal during Ramadan fasting might increase the IOP and tear secretion in the early morning period and these values decrease remarkably at the end of 12 h of fasting due to dehydration.

No abstract

Tear secretion, tear film stability, and meibomian gland function (plugging, volume, and thickness) were assessed in patients with psoriasis vulgaris (n = 70). As compared to that of the healthy controls (n = 125) mean Schirmer I value of psoriatic patients was found to be in normal ranges, whereas tear film break-up time was significantly lowered. When evaluating meibomian gland function, psoriatic patients were found to have higher plugging and thickness indices but a normal volume of meibomian gland secretion. These findings suggested an obstructive type of meibomian gland dysfunction in psoriatic patients which might result from increased turnover of the epithelia lining the meibomian gland duct.

No abstract

group after euthyroidism was achieved, which denotes improvement in color contrast sensitivity. Conclusions: It is a novel finding of the current study that color contrast sensitivity is impaired in hypothyroidism and significantly improves after euthyroidism is achieved.

Color-tinted contact lenses were associated with a reduction of contrast sensitivity function. Therefore, those who wear colored contact lenses should be informed about the possible consequences of tinted contact lens wearing.

Background:Acute pulmonary embolism (PE) is a life-threatening and a relatively common cardiovascular pathology. Although the pathogenesis of PE is well defined, there is no ideal diagnostic biochemical marker. Previous studies showed an increased ischemia modified albumin (IMA) levels in acute PE; however, the relationship between IMA and right ventricular (RV) dysfunction has not been examined. The aim of this study was to evaluate the diagnostic value of IMA and the relationship with RV dysfunction in acute PE.MATERIALS AND METHODS:A total of 145 patients (70 females) with suspected acute PE was enrolled to the study. Eighty-nine patients were diagnosed with acute PE via computed tomographic pulmonary angiography. Sixty-five patients with similar demographic and clinical characteristics were assigned to the control group. All patients were evaluated for RV dysfunction using transthoracic echocardiography.Results:Serum IMA levels were significantly increased in acute PE compared with control group (0.41 ± 0.06 vs. 0.34 ± 0.11, P = 0.001). There was no relationship between serum IMA levels and RV dysfunction. IMA levels were positively correlated with shock index and heart rate. Receiver operating curve analysis demonstrated that serum IMA levels higher than 0.4 put the diagnosis at sensitivity of 53.85% and at specificity of 85.96%.Conclusions:Although IMA levels are increased in patients with acute PE, it failed to predict RV dysfunction.