scholarly journals Increased Corneal Toricity after Long-Term Orthokeratology Lens Wear

2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Zhi Chen ◽  
Jiaqi Zhou ◽  
Feng Xue ◽  
Xingtao Zhou ◽  
Xiaomei Qu

Purpose. To investigate the change in corneal toricity and associated refractive astigmatism after discontinuation of long-term orthokeratology (ortho-k) lens wear. Methods. This study investigated 136 subjects aged between 6 and 14 (9.1 ± 1.5) years old at the commencement of ortho-k treatment, who had been undergoing overnight ortho-k treatment for 24 to 72 (37.4 ± 11.9) months. Corneal refractive power and manifest refraction were measured and compared before ortho-k and 1 month after discontinuation of ortho-k lens wear. Changes in corneal curvature were analyzed. Corneal curvature data from a historical longitudinal study were used as control. Results. Compared to pre-ortho-k values, the corneal curvature became significantly flatter in the flatter meridian (−0.22 ± 0.27 D, P<0.001) and steeper in the steeper meridian (0.06 ± 0.34 D, P=0.032) after cessation of ortho-k lens wear, resulting in a significant increase in corneal toricity (0.28 ± 0.43 D, P<0.001), which is associated with an increase in refractive astigmatism (0.57 ± 0.57 D, r=0.465, P<0.001). The amount of residual corneal flattening in the flatter meridian is significantly affected by the length of ortho-k treatment (t=−2.965, P=0.004) and the baseline age of subject (t=−2.841, P=0.005), but not by the baseline spherical or cylindrical refractive error (both P>0.05). In the historical control group, there is no significant change in the corneal curvature over two years in children wearing spectacle lenses (both meridians, P>0.05). Change of corneal toricity was more significant in the ortho-k group than in the spectacle control group (P=0.001). Conclusions. Long-term ortho-k lens wear increases corneal toricity after discontinuation of the treatment, which is associated with an increase in refractive astigmatism. A more pronounced change in corneal toricity was found in subjects who were younger to start ortho-k and have been in a longer period of treatment. This trial is registered with http://www.chictr.org.cn (ChiCTR-TNRC-11001210).

2016 ◽  
Vol 5 ◽  
Author(s):  
Wei Wang ◽  
Jerome Hernandez ◽  
Cecil Moore ◽  
Janet Jackson ◽  
Kristina Narfström

AbstractThe objective of the study was to examine whether a nutritional antioxidant supplementation could improve visual function in healthy dogs as measured by electroretinography (ERG) and autorefraction. A total of twelve Beagles, 6 to 8 years of age, with normal eyes upon indirect ophthalmoscopy and slit lamp biomicroscopy, were age and sex matched and randomly assigned to receive a feeding regimen for 6 months with or without a daily antioxidant supplementation. Portable, mini-Ganzfeld ERG and a Welch Allyn hand-held autorefractor were used to test retinal response and refractive error in the dogs at baseline and at the end of the supplementation period. All ERG a-wave amplitudes obtained were increased in the treatment group compared with those of dogs in the control group, with significant improvements in the scotopic high and photopic single flash cone ERG responses (P < 0·05 for both). For the b-wave amplitudes, all responses were similarly increased, with significant improvements in responses for the scotopic high light intensity stimulation (P < 0·05), and for photopic single flash cone and 30 Hz flicker (P < 0·01 for both) recordings. Change in refractive error was significantly less in the treatment group compared with that of the control group during the 6-month study (P < 0·05). Compared with the control group, the antioxidant-supplemented group showed improvement to varying degrees for retinal function and significantly less decline in refractive error. Dogs, like humans, experience retinal and lens functional decline with age. Antioxidant supplementation as demonstrated may be beneficial and effective in the long-term preservation and improvement of various functions of the canine eye.


VASA ◽  
2005 ◽  
Vol 34 (4) ◽  
pp. 243-249 ◽  
Author(s):  
Drinda ◽  
Neumann ◽  
Pöhlmann ◽  
Vogelsang ◽  
Stein ◽  
...  

Background: Prostanoids are used in the treatment of Raynaud’s phenomenon and acral perfusion disorders secondary to collagenosis. In subjective terms, intravenous administration of these agents produces success in more than 50% of patients. The therapeutic outcome of clinical administration of alprostadil or iloprost may vary from individual to individual. Patients and methods: The following variables were analysed in a cross-over study in 27 patients with collagenosis and Raynaud’s phenomenon: plasma viscosity and erythrocyte aggregation (rheological variables), partial pressure of oxygen and laser Doppler flowmetry in the finger region, and lymphocyte phenotyping and interleukin (IL) determinations (immunological variables). Results: Laser Doppler flowmetry revealed significant differences between patients with secondary Raynaud’s phenomenon and a control group of 25 healthy subjects. Laser Doppler readings did not change significantly as a result of the treatments. Therapy with iloprost produced a reduction in IL-1beta, L-selectin (CD 62 L) and IL-6. Conclusion: The change in immunological variables due to iloprost may explain the long-term effects of prostaglandins in the treatment of Raynaud’s phenomenon. From our results it is not possible to infer any preference for iloprost or alprostadil.


1987 ◽  
Vol 57 (01) ◽  
pp. 55-58 ◽  
Author(s):  
J F Martin ◽  
T D Daniel ◽  
E A Trowbridge

SummaryPatients undergoing surgery for coronary artery bypass graft or heart valve replacement had their platelet count and mean volume measured pre-operatively, immediately post-operatively and serially for up to 48 days after the surgical procedure. The mean pre-operative platelet count of 1.95 ± 0.11 × 1011/1 (n = 26) fell significantly to 1.35 ± 0.09 × 1011/1 immediately post-operatively (p <0.001) (n = 22), without a significant alteration in the mean platelet volume. The average platelet count rose to a maximum of 5.07 ± 0.66 × 1011/1 between days 14 and 17 after surgery while the average mean platelet volume fell from preparative and post-operative values of 7.25 ± 0.14 and 7.20 ± 0.14 fl respectively to a minimum of 6.16 ± 0.16 fl by day 20. Seven patients were followed for 32 days or longer after the operation. By this time they had achieved steady state thrombopoiesis and their average platelet count was 2.44 ± 0.33 × 1011/1, significantly higher than the pre-operative value (p <0.05), while their average mean platelet volume was 6.63 ± 0.21 fl, significantly lower than before surgery (p <0.001). The pre-operative values for the platelet volume and counts of these patients were significantly different from a control group of 32 young males, while the chronic post-operative values were not. These long term changes in platelet volume and count may reflect changes in the thrombopoietic control system secondary to the corrective surgery.


2004 ◽  
Vol 35 (03) ◽  
Author(s):  
S Schnaudigel ◽  
T Ugur ◽  
F Kruggel ◽  
HJ Mentzel ◽  
C Fitzek ◽  
...  

Author(s):  
Blaurock-Busch E

The heavy metal burden of patients with Autism spectrum disorders (ASD) has been widely discussed [1-5]. Present knowledge suggests that ASD patients, compared to ‘normal’s’ show a greater metal burden, which may be a cause of the ASD pathogenesis, possibly due to a limited detoxification potential. We thus aimed to evaluate if the metal burden of ASD children is due to comprised detoxification ability, and if missing of enzymes such as the glutathione-S-transferases provide an explanation, or if additional factors play a role. Genetically, we noticed a slight difference in the detoxification ability of the ASD group compared to the Control group. In the ASD group, carrier of the genotype GSTT1 null genotype (i.e. the homozygous loss) are 1.7 times more common as in the Control group and the GSTT1 allele is more frequent in the ASD patient collective. These findings are not statistically significant but indicate a trend. In addition, our data indicates that levels of potentially toxic metals in blood and hair of both groups demonstrate a similar immediate and long-term exposure. However, 36% of the ASD group showed signs of zinc deficiency compared to 11% of the Control group and this points towards inefficiency of the Phase I detoxification pathway. More research is needed to explore the role of other elements in the detoxification pathway.


2019 ◽  
Author(s):  
Francisco Jesús Represas Carrera Sr ◽  
Ángel Alfredo Martínez Ques Sr ◽  
Ana Clavería Fontán Sr

BACKGROUND Diabetes mellitus is currently a major public health problem worldwide. It is traditionally approached in a clinical inpatient relationship between the patient and the healthcare professional. However, the rise of new technologies, particularly mobile applications, is revolutionizing the traditional healthcare model through the introduction of telehealthcare. OBJECTIVE (1) To assess the effects of mobile applications for improving healthy lifestyles on the quality of life and metabolic control of diabetes mellitus in adult patients. (2) To describe the characteristics of the mobile applications used, identify the healthy lifestyles they target, and describe any adverse effects their use may have. METHODS Review of systematic reviews and meta-analysis, following the guidelines of the Cochrane Collaboration and the Joanna Briggs Institute. We included studies that used any mobile application aimed at helping patients improve self-management of diabetes mellitus by focusing on healthy lifestyles. Studies needed to include a control group receiving regular care without the use of mobile devices. In May 2018, a search was conducted in Medline, Embase, Cochrane, LILACS, PsychINFO, Cinahl and Science Direct, updated in May 2019. The methodological quality of the studies was assessed using the Amstar-2 tool. RESULTS Seven systematic reviews of 798 articles were initially selected for analysis. The interventions had a duration of between 1 and 12 months. Mobile applications focused singly or simultaneously on different lifestyles aspects (diet, physical exercise, motivation, blood glucose levels, etc.). There are significant changes in HbA1c values, body weight and BMI, although in others, such as lipid profile, quality of life, or blood pressure, there is no clear improvement. CONCLUSIONS There is clear evidence that the use of mobile applications improves glycemic control in diabetic patients in the short term. There is a lack of evidence in its long-term benefits. It is thus necessary to carry out further studies to learn about the long-term effectiveness of mobile applications aimed at promoting the healthy lifestyles of diabetic patients. CLINICALTRIAL PROSPERO Register: CRD42019133685


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