Photorefractive Keratectomy for Mild-to-Moderate Myopics with Thin Corneas: A 3-Year Follow-up Results

Background: The purpose of this study was to evaluate the 3-year visual outcomes in mild-to-moderate myopic patients with thin corneas who underwent photorefractive keratectomy (PRK) with or without mitomycin C (MMC).Methods: Thirty myopic eyes with a mean spherical equivalent (SE) of −3.76 ± 1.72 (−6.50 to −1.25) diopter (D) and a mean corneal thickness of 486.03 ± 11.93 (452-499) µm at the thinnest point underwent PRK. MMC was used if they had > 4.0 D myopia. All surgeries were performed with the VISX STAR S4 Excimer Laser (Abbott Medical Optics, Abbott Park, Illinois, USA).Results: Uncorrected visual acuity showed a significant improvement 3 years after surgery when compared to baseline and reached 0.01 ± 0.04 LogMAR (P < 0.001). Best-corrected visual acuity was 0.00 ± 0.01 LogMAR preoperatively and did not change significantly postoperatively. Spherical (P < 0.001) and cylindrical (P < 0.001) error significantly decreased. Manifest refraction SE showed a significant decrease when compared to before the operation and reached −0.08 ± 0.16 D (P < 0.001). At 3 years, mesopic contrast sensitivity was not significantly different from baseline at any spatial frequency. Vertical coma showed a significant decrease and reached −0.10 ± 0.27 µm (P = 0.004). Total coma (P < 0.001), spherical aberration (P < 0.001), and total high order aberrations (P < 0.001) also increased significantly.Conclusions: Based on the 3-year results, PRK (+MMC in patients with SE > 4.0 D) is a safe, effective, and predictable treatment option for mild-to-moderate myopic patients whose minimum corneal thickness is < 500 µm

An investigation into the effect of Likert's leadership styles on empowering Iran insurance company's staff

This case study was carried out in Iran Insurance Company in the area of Hamadan city in September, 2013. The statistical population of the study consisted of 144, the whole body of which was taken as sample to raise more accuracy and have access to it. The sampling method is of simple randomized kind. The means of collecting data is questionnaire. In order to assess the validity of the questionnaire, the formal method was used as Cronbach Alpha with 83.0 and 75.0 values was taken for its reliability. The results showed that main hypothesis about the significant relationship between Likert leadership styles and empowering staff is confirmed. These breakthroughs revealed that empowering staff can be developed

An investigation into the effect of Likert's leadership styles on empowering Iran insurance company's staff

This case study was carried out in Iran Insurance Company in the area of Hamadan city in September, 2013. The statistical population of the study consisted of 144, the whole body of which was taken as sample to raise more accuracy and have access to it. The sampling method is of simple randomized kind. The means of collecting data is questionnaire. In order to assess the validity of the questionnaire, the formal method was used as Cronbach Alpha with 83.0 and 75.0 values was taken for its reliability. The results showed that main hypothesis about the significant relationship between Likert leadership styles and empowering staff is confirmed. These breakthroughs revealed that empowering staff can be developed

Outpatient and Hospitalization in Cataract Surgery: Iranian Cataract Surgery Survey

Background: To determine the prevalence of outpatient and hospitalization for cataract surgery in Iran.Methods: A random cluster sampling was done in a cross-sectional study on cataract surgeries performed in treatment centers of ophthalmology in Iran between 2000 and 2005. One week of each season was selected randomly and all cataract surgery files of the center were studied. This study reported the prevalence of outpatient surgery and length of hospital stay in all surgeries in Iran between 2000 and 2005.Results: Among 13,409 studied files on cataract surgery, mean hospitalization time was 0.79±0.82 days, 31.42% of surgeries were done on an outpatient basis, and 62.32% were hospitalized for one night. About 4.45% and 1.81% were hospitalized for two nights and more, respectively. Hospitalization time after surgery showed no significant difference with sex. Also, There was no significant difference between mean age of inpatients and outpatients (P=0.08). The most common method used for surgeries was Phaco (52.33%) and the least was lensectomy (11.38%).Conclusions: A major proportion of cataract surgeries required hospitalization. Due to the costs of hospitalization in this surgery, the phaco method can play an important role in reducing the costs of treatment.

Small diameter helical vascular scaffolds support endothelial cell survival.

There is an acute clinical need for small-diameter vascular grafts as a treatment option for cardiovascular disease. Here, we used an intelligent design system to recreate the natural structure and hemodynamics of small arteries. Nano-fibrous tubular scaffolds were fabricated from blends of polyvinyl alcohol and gelatin with inner helices to allow a near physiological spiral flow profile, using the electrospinning technique. Human coronary artery endothelial cells (ECs) were seeded on the inner surface and their viability, distribution, gene expression of mechanosensitive and adhesion molecules compared to that in conventional scaffolds, under static and flow conditions. We show significant improvement in cell distribution in helical vs. conventional scaffolds (94% ± 9% vs. 82% ± 7.2%; P < 0.05) with improved responsiveness to shear stress and better ability to withhold physiological pressures. Our helical vascular scaffold provides an improved niche for EC growth and may be attractive as a potential small diameter vascular graft

Outpatient and Hospitalization in Cataract Surgery: Iranian Cataract Surgery Survey

Background: To determine the prevalence of outpatient and hospitalization for cataract surgery in Iran.Methods: A random cluster sampling was done in a cross-sectional study on cataract surgeries performed in treatment centers of ophthalmology in Iran between 2000 and 2005. One week of each season was selected randomly and all cataract surgery files of the center were studied. This study reported the prevalence of outpatient surgery and length of hospital stay in all surgeries in Iran between 2000 and 2005.Results: Among 13,409 studied files on cataract surgery, mean hospitalization time was 0.79±0.82 days, 31.42% of surgeries were done on an outpatient basis, and 62.32% were hospitalized for one night. About 4.45% and 1.81% were hospitalized for two nights and more, respectively. Hospitalization time after surgery showed no significant difference with sex. Also, There was no significant difference between mean age of inpatients and outpatients (P=0.08). The most common method used for surgeries was Phaco (52.33%) and the least was lensectomy (11.38%).Conclusions: A major proportion of cataract surgeries required hospitalization. Due to the costs of hospitalization in this surgery, the phaco method can play an important role in reducing the costs of treatment.

Two-year results of femtosecond assisted LASIK versus PRK for different severity of astigmatism

Purpose: To compare two-year results of femtosecond laser assisted LASIK (femto-LASIK) and photorefractive keratectomy (PRK) in terms of astigmatism correction in patients with less than 2.0 diopters (D) of spherical error and more than 2.0 D of cylinder error. Methods: In this retrospective study, data were extracted from 100 patient charts. The two study groups were matched by age, gender, and baseline uncorrected distance visual acuity (UDVA) and refractive astigmatism (RA). Preoperative astigmatism was categorized as mild: 2.00 to <3.00 D, moderate: 3.00 to <4.00 D, and severe: ≥4.00 D. Results: Mean RA in the femto-LASIK and PRK groups was respectively −3.15 ± 0.94 D (−7.00 to −2.00 D) and −3.29 ± 0.95 D (−6.25 to −2.00 D) at baseline (P = 0.284), and −0.61 ± 0.40 D and −0.62 ± 0.60 D one year after surgery (P = 0.674), but significantly lower in the femto-LASIK group (−0.61 ± 0.39 vs. −0.83 ± 0.56 D, P = 0.021) at 2 years when the rate of residual astigmatism more than 1.0 D was 6.3% in the femto-LASIK and 19.6% in the PRK group (P = 0.046). Mean UDVA in the femto-LASIK group (0.02 ± 0.05 logMAR) was better than the PRK group (0.06 ± 0.10 logMAR) (P = 0.025). Mean corrected distance visual acuity (CDVA) was not significantly different between groups (0.01 ± 0.03 vs. 0.01 ± 0.04 logMAR, P = 0.714). Both groups had 1–4 Snellen lines CDVA improvement. The three subgroups of baseline astigmatism did not differ significantly in terms of residual astigmatism (all P > 0.05). However, in subgroups with ≥4.00 D cylinder, there was less astigmatic regression at 1 year in the femto-LASIK group (0.28 ± 0.43 D) than the PRK group (0.54 ± 0.68 D) (P = 0.007). Conclusions: Our results pointed to better two-year results with femto-LASIK in the treatment of different degrees of astigmatism. UDVA improvement was superior with femto-LASIK, but the two methods did not significantly differ in terms of CDVA improvement

Photorefractive keratectomy results in myopic patients with thin cornea eyes

Background: To evaluate the results of visual acuity and quality, and corneal integrity in myopic patients with a thin cornea who received photorefractive keratectomy (PRK). Materials and Methods: In this before-after interventional study, 30 myopic eyes with a myopia −3.76 ± 1.72 (−6.50 to −1.25) D and a corneal thickness of 486.03 ± 11.93 (452-499) μm at the thinnest point received PRK. In myopia was more than 4D, mitomycin C was used with PRK. The surgery was performed with an excimer laser (VISX STAR, Abbott Medical Optics, Abbott Park, US). Results: The safety and the efficacy index of the surgery was 1.01 ± 0.05 and 1.00 ± 0.05 in these patients, respectively. All the patients were within ±0.5D of emmetropia 1 year after the surgery. Mesopic contrast sensitivity (CS) had a significant increase in two spatial frequencies of six (P = 0.003) and 12 (P = 0.003). Total coma (P < 0.001), spherical aberration (P < 0.001), and total higher-order aberrations (HOA) (P < 0.001) also showed a significant increase. Corneal hysteresis (P < 0.001) and corneal resistance factor (P < 0.001) showed a significant decrease after 1 year. Conclusion: PRK is a safe, effective, and predictable procedure with desirable effects on mesopic CS in patients with corneal thickness <500 μm, which increases HOAs and decreases corneal integrity proportionate to its value before the procedure