ABSTRACT
Purpose: To analyze different tomographic and refractive parameters for predicting successful visual outcome following femtosecond laser-assisted arcuate keratotomy (FSAK) for post-keratoplasty astigmatism. Design: Retrospective. Methods: Retrospective study evaluating patients with astigmatism following penetrating keratoplasty (PKP) or deep anterior lamellar keratoplasty (DALK) who underwent FSAK. Vector analysis using the Alpins method was done to calculate surgically induced astigmatism (SIA). An improvement of 3 lines of Early Treatment Diabetic Retinopathy Study (ETDRS) lines was used for successful outcome. Outcome was measured at 3 months and 17 months. Results: This study included 106 eyes from 104 patients (65 males and 39 females). Mean age was 31.8±8.6 years, and 89.4% (n=93) of cases were keratoconus (KC), 3.8% (n=4) scar, 3.8% (n=4) granular dystrophy, 1.9% (n=2) post-LASIK ectasia, and 1.0% (n=1) macular dystrophy. Uncorrected visual acuity (UCVA) improved from 1.02±0.53 logarithm minimal angle of resolution (logMAR) to 0.87±0.49 logMAR (p=0.01) at 3 months and to 0.92±1.08 logMAR (p=0.57) at 17 months. Best spectacle-corrected visual acuity (BSCVA) improved from 0.41±0.30 logMAR to 0.31±0.19 logMAR (p<0.01) at 3 months and to 0.23±0.27 logMAR (p<0.01) at 17 months. Success was achieved in 50% (n=53) and 49% (n=52) at 3 and 17 months follow-up, respectively. Success group showed worse preoperative UCVA (1.21±0.56 vs 0.83±0.44 logMAR; p<0.01), worse preoperative BSCVA (0.50±0.36 vs 0.33±0.19 logMAR; p=0.01). Preoperative UCVA had an area under the curve of 0.721 (95% CI: 0.622-0.820; p< 0.01). The Youden's optimal cutoff point was 0.90 logMAR (equivalent Snellen 20/159) with 76.9% sensitivity and 35.2% specificity. Flattening index (FI) was 87% in DALK and 73% in PKP (p=0.14). Correction index (CI) was 99% and 86% (p=0.18) for DALK and PKP, respectively. Success of the astigmatic surgery for DALK and PKP was 44% vs 42% (p=0.29), respectively. Conclusion: Improvement of at least three lines was achieved in 49% of patients who underwent FSAK following PKP or DALK; this improvement was achieved in patients who had a worse preoperative UCVA.
ABSTRACT
OBJECTIVES: To determine the prevalence of refractive errors among freshman students of Imam Abdulrahman Bin Faisal University (IAU), and to examine the relationship of near-work activities and outdoor activities with refractive errors. METHODS: A cross-sectional study of 338 freshman students of IAU (162 males, 176 females) was carried out. Students were selected using a simple random sampling technique. Eye examination was done including non-cycloplegic autorefraction for determining the refractive error status. Myopia was defined as spherical equivalent refraction (SER) ≤-0.75 diopters (D), and it was further divided into low myopia (SER from -0.75 D to -2.99 D), moderate myopia (SER from -3.00 to -5.99 D), and high myopia (SER ≤-6.00 D). Hyperopia was defined as SER ≥1.00 D and emmetropia as having an SER value between that of low myopia and hyperopia. SER was calculated as sphere + 1/2 cylinder. A questionnaire detailed on activities was completed by participants. RESULTS: Myopia was found in 47.9% of the students (95% CI 42.7%-53.3%). The most prevalent type of myopia was low myopia (66.7%; 95% CI 59.1%-73.5%). Hyperopia and emmetropia were found in 6.5% (95% CI 4.3%-9.7%) and 45.6% (95% CI 40.3%-50.9%) of the students, respectively. Parental myopia was significantly associated with the myopic status of the students (P=0.007, Fisher's exact test). About 6% of myopic students had a history of myopia in both parents. In addition, both parents had a history of myopia in 1.9% of emmetropic students, whereas such an association was absent in the hyperopic students. Refractive error type in both genders was not significantly predicted by the activity type. CONCLUSION: Although the different types of activities did not predict the types of refractive errors, the high prevalence of myopia among the college students at this age requires further studies to explore more about the clinical characteristics and risk factors of the disease.
ABSTRACT
BACKGROUND The introduction of bioresorbable vascular scaffolds (BVS) into the field of percutaneous coronary intervention (PCI) was thought to be a promising step in solving the issues raised with the use of early bare metal stents (BMS) and drug eluting stents (DES); however, studies have raised concerns regarding thrombosis risk associated with the use of these stents. CASE REPORT A 42-year-old male presented with acute coronary syndrome (ACS), on diagnostic coronary angiography he had 75% and 70% stenosis in mid and distal left anterior descending artery (LAD) respectively, PCI with BVS implantation was done. A week later, he came with non-ST segment elevation myocardial infarction due to an in-stent thrombosis. Procedures to open the LAD were done with multiple balloon angioplasties and aspiration thrombectomy, following aggressive dilatation there was a class-III perforation which was sealed by covered stent. A second look angiography was done which showed patent LAD and well expanded stents. CONCLUSIONS Since several factors play a role in decision-making regarding the selection of patient in whom BVS usage can be beneficial, larger studies are needed. Moreover, the safety profile of BVS should be investigated thoroughly.
