Test-Retest of the Spot Vision Screener among Children with Ophthalmological Diseases including Strabismus.

Background: The spot vision screener (SVS) has been widely used for eye health examinations of infants and young children. The purpose of this study was to evaluate the reproducibility of two SVS measurements in children with ophthalmological diseases. Methods: 29 patients aged 15 years or younger who visited our hospital for refraction examinations with SVS before and at least 60 minutes after administration of 2 drops of 1% cyclopentolate ophthalmic solution (before and after cycloplegia) were included in this study. Two SVS measurements were made before and after cycloplegia, respectively. Intraclass correlation coefficients (ICCs) and Bland-Altman analysis for spherical, spherical equivalent (SE), cylindrical, J0, and J45 values before and after cycloplegia were analyzed. Results: The mean age ± standard deviation (SD) of the 29 patients was 7.6 ± 2.4 years. There were 11 males and 18 females. The mean spherical values based on the SVS before and after cycloplegia were 0.42 ± 1.67 diopter (D), and 1.47 ± 2.23 D for the first measurement and 0.60 ± 1.74 D, and 1.42 ± 2.27 D for the second measurement, respectively. The mean cylindrical values based on SVS before and after cycloplegia were -1.45 ± 0.96 D and -1.65 ± 0.89 D for the first measurement and -1.58 ± 1.13 D and -1.66 ± 0.91 D for the second measurement, respectively. The ICCs for the first and second spherical, SE, cylindrical, J0, and J45 values before cycloplegia were 0.95, 0.98, 0.83, 0.86, and 0.86, respectively. The ICCs for the first and second spherical, SE, cylindrical, J0, and J45 values after cycloplegia were 0.99, 0.99, 0,87, 0.73, and 0.80, respectively. The Bland-Altman analysis of the first and second spherical and SE values before cycloplegia showed fan-shaped variation as hyperopia increased. Conclusions: Two consecutive SVS refraction measurements have a high degree of reproducibility for spherical and SE values but a low degree for cylindrical, J0, and J45 values. From these results, multiple measurements are required to obtain reliable results for cylindrical values.

Efficient measurements for the dynamic range of human lightness perception.

PURPOSE: Patients with an eye disease often report nyctalopia, hemianopia, and/or photophobia. We hypothesized that such symptoms are related to the disease impacting the dynamic range of lightness perception (DRL). However, there is currently no standardized approach for measuring DRL for clinical use. We developed an efficient measurement method to estimate DRL. STUDY DESIGN: Clinical trial METHODS: Fifty-five photophobic patients with eye disease and 46 controls participated. Each participant judged the appearance of visual stimuli, a thick bar with luminance that gradually changed from maximum to minimum was displayed on uniform background. On different trials the background luminance changed pseudo-randomly between three levels. The participants repeatedly tapped a border on the bar that divided the appearance of grayish white/black and perfect white/black. We defined the DRL as the ratio between the luminance values at the tapped point of the border between gray and white/black. RESULTS: The mean DRL of the patients was approximately 15 dB, significantly smaller than that of the controls (20 dB). The center of each patient's DRL shift depending on background luminance, which we named index of contextual susceptibility (iCS), was significantly larger than controls. The DRL of retinitis pigmentosa was smaller than controls for every luminance condition. Only the iCS of glaucoma was significantly larger than controls. CONCLUSIONS: This measurement technique detects an abnormality of the DRL. The results support our hypothesis that the DRL abnormality characterizes lightness-relevant symptoms that may elucidate the causes of nyctalopia, hemeralopia, and photophobia.

Tapping enhances vasodilation for venipuncture even in individuals with veins that are relatively difficult to palpate.

INTRODUCTION: This study evaluated whether tapping enhances vasodilation in individuals with veins that are relatively difficult to palpate. MATERIALS AND METHODS: Twenty participants (4 men and 16 women, aged 19-22 years) with cutaneous veins that were relatively difficult to palpate even after tourniquet application were recruited. A crossover trial with/without tapping (10 times in 5 s) was performed under tourniquet inflation on the upper arm. Vasodilation was evaluated by venous cross-sectional area, depth of the vein, and elevation of the overlying skin by ultrasonography. Venous palpation scores were also measured. The degree of improvement was estimated by simulation. RESULTS: In total, 60% of participants "sometimes" or "often" experienced unsuccessful venipuncture. After the tapping procedure, the venous cross-sectional area significantly increased (14.6 ± 9.12 mm2 for control and 15.2 ± 9.79 mm2 for tapping) and venous depth significantly decreased (4.57 ± 2.31 mm for control and 4.23 ± 2.41 mm for tapping). A simulation study using these values suggested that tapping increased the longitudinal and crosswise successful ranges of venipuncture by 5-6%. CONCLUSIONS: Tapping in this study enhanced the vasodilation of cutaneous veins that are relatively difficult to palpate. The effectiveness of various vasodilation methods may be compared through the estimation of improvement.

Tapping but not massage enhances vasodilation and improves venous palpation of cutaneous veins.

This paper investigated whether tapping on the median cubital vein or massaging the forearm was more effective in obtaining better venous palpation for venipuncture. Forty healthy volunteers in their twenties were subjected to tapping (10 times in 5 sec) or massage (10 strokes in 20 sec from the wrist to the cubital fossa) under tourniquet inflation on the upper arm. Venous palpation was assessed using the venous palpation score (0-6, with 0 being impalpable). Three venous factors-venous depth, cross-sectional area, and elevation-were also measured using ultrasonography. The venous palpation score increased significantly by tapping but not by massage. Moreover, all 3 venous measurements changed significantly by tapping, while only the depth decreased significantly by massage. The three venous measurements correlated significantly with the venous palpation score, indicating that they are useful objective indicators for evaluating vasodilation. We suggest that tapping is an effective vasodilation technique.

The characteristics of healthy adults with hardly palpable vein--Relations between easy venous palpation and physical factors.

This study aimed to investigate relations between ease of venous palpation and various venous factors, and to elucidate characteristics of hardly palpable veins. Healthy adult volunteers (n = 110) were enrolled. The ease of venous palpation was scored from 0: impalpable to 3: well palpable. Venous factors, namely venous depth, elevation, area and minimal pressure that starts to collapse vein, were measured using an ultrasonography before and after tourniquet inflation at 60 mmHg for 60 s. Tourniquet inflation significantly increased the venous area and venous palpation score. The four venous factors correlated significantly with venous palpation score with the following correlation coefficient: Depth (r = -0.542), Elevation (0.486), area (0.258) and start-to-collapse pressure (-0.220). The characteristics of hardly palpable veins were small size, deep location and little elevation. Although vasodilatation facilitated venous palpation, venous depth and elevation were also important and should be included in future studies in which vasodilatation methods are evaluated.

Relationship between tourniquet pressure and a cross-section area of superficial vein of forearm.

This study investigated the appropriate tourniquet pressure (TP) and duration of tourniquet application for venipuncture by calculating the venous cross-section (VCS) area on ultrasonography. Twenty healthy volunteers without cardiovascular risk factors were enrolled in this study. A target vein (either a cephalic or median cubital vein) was selected on ultrasonography. The pneumatic tourniquet was inflated using a rapid cuff inflator system at setting pressure for 120 sec. TP strength was varied from 20 mmHg to 100 mmHg, in 20 mmHg increments. The order of TP was randomized. Comparisons among more than 3 groups were performed by one-way repeated-measures ANOVA and the Bonferroni method. The VCS area increased rapidly until 10 sec after tourniquet inflation. The VCS area then increased gradually until 30 sec after tourniquet inflation. After that, the VCS area did not increase remarkably. The VCS area increased with TP strength up to 80 mmHg, but the VCS area at TP 100 mmHg decreased to less than that at TP 40 mmHg. Based on these results, we recommend a tourniquet pressure of 60 mmHg, and duration of tourniquet application is 30 to 60 sec for venipuncture.

Effects of astaxanthin and vitamin C on the prevention of gastric ulcerations in stressed rats.

Astaxanthin (Asx), one of the carotenoids, is a red pigment in fish and Crustaceans, and possesses stronger reduction properties than conventional carotenoids, like beta-carotene. However, little is known about the biochemical properties and physiological functions of astaxanthin. The effects of astaxanthin and vitamin C on stressed rats were studied physiologically and biochemically. beta-Carotene and three kinds of astaxanthins, which were extracted from Haematococcus and Phaffia, and synthesized chemically, were used in these experiments. These rats given astaxanthins or beta-carotene had stress induced on the 12th day by immersing the rats in chest-level water at 20 degrees C for 24 h after fasting for 24 h. Rats given astaxanthins or beta-carotene prior to stressing were appreciably protected against the evolution of gastric ulcerations in relation to control rats. Ulcer indexes in particular were smaller with the rat group fed astaxanthin extracted from Haematococcus than the other groups. Next, the effects of Asx and/or vitamin C on the protection of evolution of gastric ulcer in stressed rats were persued by the same methods as described above. The results showed that rats given Asx or vitamin C were appreciably protected against the evolution of gastric ulcerations in relation to control rats. The effects were more intense, especially in rats simultaneously supplied Asx and vitamin C than in rats taking either Asx or vitamin C. It was suggested that the simultaneous supplementation of food substances with astaxanthin and vitamin C would supply enough antioxidants to offset stress-related injuries.