Trifocal intraocular lenses versus bifocal intraocular lenses after cataract extraction among participants with presbyopia.

BACKGROUND: Presbyopia occurs when the lens of the eyes loses its elasticity leading to loss of accommodation. The lens may also progress to develop cataract, affecting visual acuity and contrast sensitivity. One option of care for individuals with presbyopia and cataract is the use of multifocal or extended depth of focus intraocular lens (IOL) after cataract surgery. Although trifocal and bifocal IOLs are designed to restore three and two focal points respectively, trifocal lens may be preferable because it restores near, intermediate, and far vision, and may also provide a greater range of useful vision and allow for greater spectacle independence in individuals with presbyopia. OBJECTIVES: To assess the effectiveness and safety of implantation with trifocal versus bifocal IOLs during cataract surgery among people with presbyopia. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2022, Issue 3); Ovid MEDLINE; Embase.com; PubMed; ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 31 March 2022.  SELECTION CRITERIA: We included randomized controlled trials that compared trifocal and bifocal IOLs among participants 30 years of age or older with presbyopia undergoing cataract surgery. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology and graded the certainty of the body of evidence according to the GRADE classification. MAIN RESULTS: We identified seven studies conducted in Europe and Turkey with a total of 331 participants. All included studies assessed visual acuity using a logarithm of the minimum angle of resolution (LogMAR chart). Of them, six (86%) studies assessed uncorrected distance visual acuity (the primary outcome of this review). Some studies also examined our secondary outcomes including uncorrected near, intermediate, and best-corrected distance visual acuity, as well as contrast sensitivity. Study characteristics All participants had bilateral cataracts with no pre-existing ocular pathologies or ocular surgery. Participants' mean age ranged from 55 to 74 years. Three studies reported on gender of participants, and they were mostly women. We assessed all of the included studies as being at unclear risk of bias for most domains. Two studies received financial support from manufacturers of lenses evaluated in this review, and at least one author of another study reported receiving payments for delivering lectures with lens manufacturers. Findings All studies compared trifocal versus bifocal IOL implantation on visual acuity outcomes measured on a LogMAR scale. At one year, trifocal IOL showed no evidence of effect on uncorrected distance visual acuity (mean difference (MD) 0.00, 95% confidence interval (CI) -0.04 to 0.04; I2 = 0%; 2 studies, 107 participants; low-certainty evidence) and uncorrected near visual acuity (MD 0.01, 95% CI -0.04 to 0.06; I2 = 0%; 2 studies, 107 participants; low-certainty evidence). Trifocal IOL implantation may improve uncorrected intermediate visual acuity at one year (MD -0.16, 95% CI -0.22 to -0.10; I2 = 0%; 2 studies, 107 participants; low-certainty evidence), but showed no evidence of effect on best-corrected distance visual acuity at one year (MD 0.00, 95% CI -0.03 to 0.04; I2 = 0%; 2 studies, 107 participants; low-certainty evidence). No study reported on contrast sensitivity or quality of life at one-year follow-up. Data from one study at three months suggest that contrast sensitivity did not differ between groups under photopic conditions, but may be worse in the trifocal group in one of the four frequencies under mesopic conditions (MD -0.19, 95% CI -0.33 to -0.05; 1 study; I2 = 0%, 25 participants; low-certainty evidence). One study examined vision-related quality of life using the 25-item National Eye Institute Visual Function Questionnaire (NEI-VFQ-25) at six months, and suggested no evidence of a difference between trifocal and bifocal IOLs (MD 1.41, 95% CI -1.78 to 4.60; 1 study, 40 participants; low-certainty evidence). Adverse events Adverse events reporting varied among studies. Of five studies reporting information on adverse events, two studies observed no intraoperative and postoperative complications or no posterior capsular opacification at six months. One study reported that glare and halos were similar to the preoperative measurements. One study reported that 4 (20%) and 10 (50%) participants had glare complaints at 6 months in trifocal and bifocal group, respectively (risk ratio 0.40, 95% CI 0.15 to 1.07; 40 participants). One study reported that four eyes (11.4%) in the bifocal group and three eyes (7.5%) in the trifocal group developed significant posterior capsular opacification requiring YAG capsulotomy at one year. The certainty of the evidence for adverse events was low. AUTHORS' CONCLUSIONS: We found low-certainty of evidence that compared with bifocal IOL, implantation of trifocal IOL may improve uncorrected intermediate visual acuity at one year. However, there was no evidence of a difference between trifocal and bifocal IOL for uncorrected distance visual acuity, uncorrected near visual acuity, and best-corrected visual acuity at one year. Future research should include the comparison of both trifocal IOL and specific bifocal IOLs that correct intermediate visual acuity to evaluate important outcomes such as contrast sensitivity, quality of life, and vision-related adverse effects.

Trifocal intraocular lenses versus bifocal intraocular lenses after cataract extraction among participants with presbyopia.

BACKGROUND: Presbyopia occurs when the lens of the eyes loses its elasticity leading to loss of accommodation. The lens may also progress to develop cataract, affecting visual acuity and contrast sensitivity. One option of care for individuals with presbyopia and cataract is the use of multifocal or extended depth of focus intraocular lens (IOL) after cataract surgery. Although trifocal and bifocal IOLs are designed to restore three and two focal points respectively, trifocal lens may be preferable because it restores near, intermediate, and far vision, and may also provide a greater range of useful vision and allow for greater spectacle independence in individuals with presbyopia. OBJECTIVES: To assess the effectiveness and safety of implantation with trifocal versus bifocal IOLs during cataract surgery among participants with presbyopia. SEARCH METHODS: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (which contains the Cochrane Eyes and Vision Trials Register) (2019, Issue 9); Ovid MEDLINE; Embase.com; PubMed; ClinicalTrials.gov; and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). We did not use any date or language restrictions in the electronic search for trials. We last searched the electronic databases on 26 September 2019. We searched the reference lists of the retrieved articles and the abstracts from the Annual Meeting of the Association for Research in Vision and Ophthalmology (ARVO) for the years 2005 to 2015. SELECTION CRITERIA: We included randomized controlled trials that compared trifocal and bifocal IOLs among participants 30 years or older with presbyopia undergoing cataract surgery. DATA COLLECTION AND ANALYSIS: We used standard Cochrane methodology. MAIN RESULTS: We identified five studies conducted in Europe with a total of 175 participants. All five studies assessed uncorrected distance visual acuity (primary outcome of the review), while some also examined our secondary outcomes including uncorrected near, intermediate, and best-corrected distance visual acuity, as well as contrast sensitivity. Study characteristics All participants had bilateral cataracts with no pre-existing ocular pathologies or ocular surgery. Participants' mean age ranged from 58 to 64 years. Only one study reported on gender of participants, and they were mostly women. We assessed all the included studies as being at unclear risk of bias for most domains. Two studies received financial support from manufacturers of lenses evaluated in this review, and at least one author of another study reported receiving payments for delivering lectures with lens manufacturers. Findings All studies compared trifocal versus bifocal IOL implantation on visual acuity outcomes measured on a LogMAR scale. At one year, trifocal IOL showed no evidence of effect on uncorrected distance visual acuity (mean difference (MD) 0.00, 95% confidence interval (CI) -0.04 to 0.04; I2 = 0%; 2 studies, 107 participants; low-certainty evidence) and uncorrected near visual acuity (MD 0.01, 95% CI -0.04 to 0.06; I2 = 0%; 2 studies, 107 participants; low-certainty evidence). Trifocal IOL implantation may improve uncorrected intermediate visual acuity at one year (MD -0.16, 95% CI -0.22 to -0.10; I2= 0%; 2 studies, 107 participants; low-certainty evidence), but showed no evidence of effect on best-corrected distance visual acuity at one year (MD 0.00, 95% CI -0.03 to 0.04; I2= 0%; 2 studies, 107 participants; low-certainty evidence). No study reported on contrast sensitivity or quality of life at one-year follow-up. Data from one study at three months suggest that contrast sensitivity did not differ between groups under photopic conditions, but may be worse in the trifocal group in one of the four frequencies under mesopic conditions (MD -0.19, 95% CI -0.33 to -0.05; 1 study; I2 = 0%, 25 participants; low-certainty evidence). In two studies, the investigators observed that participants' satisfaction or spectacle independence may be higher in the trifocal group at six months, although another study found no evidence of a difference in participant satisfaction or spectacle independence between groups. Adverse events Adverse events reporting varied among studies. Two studies reported information on adverse events at one year. One study reported that participants showed no intraoperative or postoperative complications, while the other study reported that four eyes (11.4%) in the bifocal and three eyes (7.5%) in the trifocal group developed significant posterior capsular opacification requiring YAG capsulotomy. The certainty of the evidence was low. AUTHORS' CONCLUSIONS: There is low-certainty of evidence that compared to bifocal IOL, implantation of trifocal IOL may improve uncorrected intermediate visual acuity at one year. However, there is no evidence of a difference between trifocal and bifocal IOL for uncorrected distance visual acuity, uncorrected near visual acuity, and best-corrected visual acuity at one year. Future research should include the comparison of both trifocal IOL and specific bifocal IOLs that correct intermediate visual acuity to evaluate important outcomes such as contrast sensitivity and quality of life.

Amelogenin- and enamelysin (Mmp-20)-deficient mice display altered birefringence in the secretory-stage enamel organic extracellular matrix.

Dental enamel is the most mineralized tissue of vertebrate organisms. Enamel biosynthesis is initiated by the secretion, processing, and self-assembly of a complex mixture of proteins. The formation of an ordered enamel organic extracellular matrix (ECM) seems be a crucial step for the proper formation of mineral phase. Polarizing microscopy demonstrates that the ordered supramolecular structure of the secretory-stage enamel organic ECM is strongly birefringent. In the present work we analyzed the birefringence of secretory-stage enamel organic ECM in amelogenin (Amelx)- and enamelysin (Mmp20)-deficient mice. Female Amelx+/- animals showed significant reduction in optical retardation values when compared with the Amelx+/+ subgroup (p=0.0029). The secretory-stage enamel organic ECM of the Amelx-/- subgroup did not exhibit birefringence. The secretory-stage enamel organic ECM of Mmp20-/- mice showed a significant decrease in optical retardation as compared with Mmp20+/+ and Mmp20+/- mice (p=0.0000). Mmp20+/- and Mmp20+/+ mice exhibited similar birefringence (p=1.0000). The results presented here support growing evidence for the idea that the birefringence of secretory-stage enamel organic ECM is influenced by the ordered supramolecular organization of its components.

Progress in the understanding of HIV infections: a overview

The worldwide epidemic of human immunodeficiency virus (HIV) infection will likely be considered the most important public health event of the twentieth century. During the past 15 years, a wealth of information relating to the epidemiology, diagnosis, natural history, and treatment of HIV infection has accumulated. This article details the recent progress in each of these areas.