Assessment of contrast sensitivity and aberrations after photorefractive keratectomy in patients with myopia greater than 5 diopters

This study aimed to assess changes in contrast sensitivity and aberrations in cases of myopia greater than 5.0 diopter [D] who had photorefractive keratectomy [PRK]. In this semi-experimental study, 20 eyes of ten patients were studied. Inclusion criteria were at least 5.0 D of myopia, stable refraction in the past year, no history of refractive surgery, a minimum corneal thickness of 480 micro m, and having surgery in both eyes. Exclusion criteria were the presence of any corneal condition. In addition to the routine tests, aberrometry and assessment of contrast sensitivity was done using the WaveLight Allegro Analyzer and the VectorVision CSV-1000. After PRK using the Concerto Excimer Laser [WaveLight, Alcon], patients were scheduled to have follow-up visits at 1 month, 3 months, and 1 year after surgery. Contrast sensitivity with glare showed an increasing trend only at the spatial frequency of 3 cycles per degree [cpd] [P=0.013]. Contrast sensitivity without glared increased postoperatively at special frequencies of 3, 6, and 18 cpd [P<0.05]. The preoperative level of higher order aberrations root mean square [HOA RMS] of 0.24 +/- 0.08 reached 0.71 +/- 0.25 at 12 months after surgery. Assessment of comma and trefoil showed no significant difference between preoperative and postoperative values, but the amount of spherical aberration changed from a mean preoperative value of 0.0 +/- 0.09 to 0.27 +/- 0.15 at 12 months after surgery. In the treatment of myopia greater than 5.0 D, PRK with the Concerto Excimer Laser can improve contrast sensitivity in certain spatial frequencies. This is while HOA RMS and spherical aberration increase.

prevalence of attention deficit hyperactivity disorder [ADHD] among school children of Nishaboor - Iran during 2006

ADHD is the most common mental disorder in children. Awareness of students' mental health has an important role in programming for decrementing their disorders and, improving their mental health and also preventing the complications of their decreased mental health. The aim of this study was to determine the prevalence of ADHD and some of the affecting factors among school children in Nishaboor localed in the North-East of Iran. This descriptive study was done on school children in Nishaboor during 2006. Subjectes selected by stratified cluster sampling. Data collection was done using the Conner's Parent and Teacher Scale questionnaire, and each student's questionnaires were completed by both the teacher and the parents. Data analysis was performed regarding to the mean scores of teachers and parents. The score 15 was chosen as the probable indicator for ADHD. 722 students [79.6%] were involved this study. Prevalence of ADHD was 12.5%, CI95%: 10-14.8%. There was no significant difference in gender distribution. The prevalence of ADHD had a significant rise with age [P < 0.05]. The highest prevalence was in spring born and the lowest was in the summer born school children [P < 0.05]. The prevalence of ADHD had a significant relationship with father's education and was lower in students whose father had higher educations [P < 0.05]. Variables such as type of delivery, pariety, mother's education had no significant relationship with the prevalence of ADHD. In this study the prevalence of ADHD is higher than similar studies. Risk groups to be followed up by the responsible organizations