Pub Date : 2018-06-13DOI: 10.5772/INTECHOPEN.73584
J. Jímenez-Roman, C. Prado-Larrea, Luis Laneri-Pusineri, R. González-Salinas
Glaucoma and cataract frequently coexist in our elderly population regardless of geo- graphical location or ethnicity. Cataract extraction alone has demonstrated to reduce intraocular pressure in eyes either with or without glaucoma. However, this chapter focuses on how cataract surgery might be combined with different glaucoma surgical procedures, such as trabeculectomy, non-penetrating procedures and minimally invasive procedures (MIGS), as well as implantation of drainage devices like the Trabectome ® and the iStent ® , both used for trabecular flow increase; the CyPass ® implant, which acts by increasing the uveoscleral flow; the XEN ® implant that facilitates the drainage of the aqueous humor from the anterior chamber to the subconjunctival space and finally the endocyclophotocoagulation that decreases the aqueous humor production. Current surgical options will be discussed, focusing on recently reported studies, analyzing the clini- cal aspects that influence the choice for each surgical treatment.
{"title":"Combined Glaucoma and Cataract: An Overview","authors":"J. Jímenez-Roman, C. Prado-Larrea, Luis Laneri-Pusineri, R. González-Salinas","doi":"10.5772/INTECHOPEN.73584","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.73584","url":null,"abstract":"Glaucoma and cataract frequently coexist in our elderly population regardless of geo- graphical location or ethnicity. Cataract extraction alone has demonstrated to reduce intraocular pressure in eyes either with or without glaucoma. However, this chapter focuses on how cataract surgery might be combined with different glaucoma surgical procedures, such as trabeculectomy, non-penetrating procedures and minimally invasive procedures (MIGS), as well as implantation of drainage devices like the Trabectome ® and the iStent ® , both used for trabecular flow increase; the CyPass ® implant, which acts by increasing the uveoscleral flow; the XEN ® implant that facilitates the drainage of the aqueous humor from the anterior chamber to the subconjunctival space and finally the endocyclophotocoagulation that decreases the aqueous humor production. Current surgical options will be discussed, focusing on recently reported studies, analyzing the clini- cal aspects that influence the choice for each surgical treatment.","PeriodicalId":357034,"journal":{"name":"Difficulties in Cataract Surgery","volume":"135 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123242476","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-06-13DOI: 10.5772/INTECHOPEN.72477
B. Komur
Standard cataract surgery is considered as low-risk surgery for both patients and the surgeon, but some eyes have higher risk of complication due to some reasons that are generally known or can be predicted preoperatively. Knowing risky eyes and management of possible complications is important point for achieving good visual outcome after cataract surgery. We issued most encountered problems during surgery and some solutions to manage these difficult cases.
{"title":"Strategies for Managing Difficult Cases","authors":"B. Komur","doi":"10.5772/INTECHOPEN.72477","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.72477","url":null,"abstract":"Standard cataract surgery is considered as low-risk surgery for both patients and the surgeon, but some eyes have higher risk of complication due to some reasons that are generally known or can be predicted preoperatively. Knowing risky eyes and management of possible complications is important point for achieving good visual outcome after cataract surgery. We issued most encountered problems during surgery and some solutions to manage these difficult cases.","PeriodicalId":357034,"journal":{"name":"Difficulties in Cataract Surgery","volume":"43 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-06-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127810105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2018-03-02DOI: 10.5772/INTECHOPEN.71799
L. Abdu
Background: Sub-Saharan Africa disproportionately accounts for high number of avoid- ably blind largely caused by cataracts. The blindness burden: Limitation in human and material resource for delivery of cata- ract surgical services, cost, gender, distance to hospital, time off for the care giver, fear of surgery, uncultured behavior of eye care personal, poor visual outcome, general govern- ments neglect of health care, lack of health insurance for vast majority of the population, healthcare funded by individuals as out of pocket despite grinding poverty, reliance on poorly coordinated and unsustainable outreach program, malpractices of quacks and traditional eye healers amongst other reasons. More than just a cataract: Cataract services require systematic evaluation of the patients’ general condition as well as the eye. Appropriate counseling is required to understand the goal and expectation of treatment. Adequate planning of surgery includes ocular biometry and provision of the appropriate intra ocular lens. The management protocol must ensure adequate measures are taken to prevent/ manage critical incidents whenever such a need arises. Conclusion: Cataract surgical services need to be patient centered with the goal of opti- mizing resources for quality outcome without compromising safety. and the underlying sclera is exposed. Limited bipolar wet field cautery may be applied to close bleeders. A horizontal incision of 6.5 to 7.0 milli meters is made 3 millimeters away from the limbus. A frown-shaped sclera incision pro-duces less astigmatism. The proximal sclera lip is gently lifted to allow using the crescent blade to construct a tunnel into the A/C. Thin tunnel roof can lead to button hole and a thick roof may lead to premature entry into the A/C. The tunnel is widened with a keratome as it enters the A/C. The internal opening should be 30% wider than the entrance wound. After administering viscoelastic material into the A/C, a lance is used to make a side port. Anterior capsulotomy is then performed. Nucleus is separated from the cor-tex by hydrodissection and maneuvered into the A/C by gentle rotation and subsequent delivery with vectis. In some instance, the surgeon may prefer to break the nucleus into halves using a pair of forceps before delivery. Viscoelastic material is used to cushion the endothelium and allow insertion, rotation, and dialing of the lens into position. The side port can be used toward this aim. With the IOL in position, any residual cortical matter and viscoelastic material are aspirated. Lens matter at the sclera tunnel entrance into the A/C is approached via the side port. Any residual viscoelastic material is aspirated. Antibiotic and steroid administration is similar to that of ECCE. MSICS was demonstrated to show
{"title":"Optimizing Outcome of Cataract Surgery in Resource Scarce Sub-Saharan Africa","authors":"L. Abdu","doi":"10.5772/INTECHOPEN.71799","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.71799","url":null,"abstract":"Background: Sub-Saharan Africa disproportionately accounts for high number of avoid- ably blind largely caused by cataracts. The blindness burden: Limitation in human and material resource for delivery of cata- ract surgical services, cost, gender, distance to hospital, time off for the care giver, fear of surgery, uncultured behavior of eye care personal, poor visual outcome, general govern- ments neglect of health care, lack of health insurance for vast majority of the population, healthcare funded by individuals as out of pocket despite grinding poverty, reliance on poorly coordinated and unsustainable outreach program, malpractices of quacks and traditional eye healers amongst other reasons. More than just a cataract: Cataract services require systematic evaluation of the patients’ general condition as well as the eye. Appropriate counseling is required to understand the goal and expectation of treatment. Adequate planning of surgery includes ocular biometry and provision of the appropriate intra ocular lens. The management protocol must ensure adequate measures are taken to prevent/ manage critical incidents whenever such a need arises. Conclusion: Cataract surgical services need to be patient centered with the goal of opti- mizing resources for quality outcome without compromising safety. and the underlying sclera is exposed. Limited bipolar wet field cautery may be applied to close bleeders. A horizontal incision of 6.5 to 7.0 milli meters is made 3 millimeters away from the limbus. A frown-shaped sclera incision pro-duces less astigmatism. The proximal sclera lip is gently lifted to allow using the crescent blade to construct a tunnel into the A/C. Thin tunnel roof can lead to button hole and a thick roof may lead to premature entry into the A/C. The tunnel is widened with a keratome as it enters the A/C. The internal opening should be 30% wider than the entrance wound. After administering viscoelastic material into the A/C, a lance is used to make a side port. Anterior capsulotomy is then performed. Nucleus is separated from the cor-tex by hydrodissection and maneuvered into the A/C by gentle rotation and subsequent delivery with vectis. In some instance, the surgeon may prefer to break the nucleus into halves using a pair of forceps before delivery. Viscoelastic material is used to cushion the endothelium and allow insertion, rotation, and dialing of the lens into position. The side port can be used toward this aim. With the IOL in position, any residual cortical matter and viscoelastic material are aspirated. Lens matter at the sclera tunnel entrance into the A/C is approached via the side port. Any residual viscoelastic material is aspirated. Antibiotic and steroid administration is similar to that of ECCE. MSICS was demonstrated to show","PeriodicalId":357034,"journal":{"name":"Difficulties in Cataract Surgery","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-03-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130246541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-20DOI: 10.5772/INTECHOPEN.72084
G. R. Bianchi
Life expectancy of the population increase and cataract development will affect all the people with aging. Cataract surgery, a worldwide performed procedure, evolves and progresses. However, different techniques exist, which could be selected for different cases. Any ideal technique should be safe, simple, fast, and easy to learn with good clinical outcome. This chapter will describe one technique to operate cataracts with those charac- teristics and to perform phacoemulsification cataract surgery without viscoelastic substance. Some advantages of this technique are related to avoiding viscoelastic potential problems, as postoperative intraocular pressure elevation or anterior chamber inflammation associated with viscoelastic. Moreover, a fundamental factor to remark is the differ- ence between work into the anterior chamber with negative pressure or positive pressure. Because the anterior chamber is maintained by the balanced salt solution with the contin- uous irrigation without viscoelastic. Performing the capsulorhexis is easier. Other advantages are shortensurgical time, fewer economical cost, andpotentiallyfewer complications. Some limitations are as follows: intraocular lens must be one piece foldable, and princi-pally, patients with corneal endothelial pathology must be excluded. Tips, step-by-step surgery, recommendations, and evolution of the technique will be described, with the wish that many surgeons will try to perform Bianchi ’ s method (bimanual, microincision phaco- emulsification cataract surgery without viscoelastic substance) for your next patient.
{"title":"Phacoemulsification Cataract Surgery without Viscoelastic Substance: Bianchi’s Method","authors":"G. R. Bianchi","doi":"10.5772/INTECHOPEN.72084","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.72084","url":null,"abstract":"Life expectancy of the population increase and cataract development will affect all the people with aging. Cataract surgery, a worldwide performed procedure, evolves and progresses. However, different techniques exist, which could be selected for different cases. Any ideal technique should be safe, simple, fast, and easy to learn with good clinical outcome. This chapter will describe one technique to operate cataracts with those charac- teristics and to perform phacoemulsification cataract surgery without viscoelastic substance. Some advantages of this technique are related to avoiding viscoelastic potential problems, as postoperative intraocular pressure elevation or anterior chamber inflammation associated with viscoelastic. Moreover, a fundamental factor to remark is the differ- ence between work into the anterior chamber with negative pressure or positive pressure. Because the anterior chamber is maintained by the balanced salt solution with the contin- uous irrigation without viscoelastic. Performing the capsulorhexis is easier. Other advantages are shortensurgical time, fewer economical cost, andpotentiallyfewer complications. Some limitations are as follows: intraocular lens must be one piece foldable, and princi-pally, patients with corneal endothelial pathology must be excluded. Tips, step-by-step surgery, recommendations, and evolution of the technique will be described, with the wish that many surgeons will try to perform Bianchi ’ s method (bimanual, microincision phaco- emulsification cataract surgery without viscoelastic substance) for your next patient.","PeriodicalId":357034,"journal":{"name":"Difficulties in Cataract Surgery","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117216643","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-20DOI: 10.5772/INTECHOPEN.72248
H. D. Silva, E. D. Silva, Maria do Carmo Tatiana Dória Silva, C. P. Dória, Cristiane Pereira Dória
In this chapter, we show the refractive error treatment result of a patient, the first author, who restarted in 2000, after a 4-year break, at the study start. According to previous pub-lications, the treatment consists of rehydration and elimination of agglutinated, dehy- drated and deposited metabolic residues in the cornea, the trabecular meshwork, the crystalline lens and the retina, as a consequence of the failure in the mechanism of intra- ocular mass transfer by forced convection. However, the forced movement of the metabolic mass to rehydrate one region can cause dehydration in another region. Therefore, the patient developed posterior and capsular cataract in their respective eyes, right and left. This dehydration, during the treatment, increases the difficulties for the success of the treatment. The first part is a chronological record of the most important components of the treatment. Then, the research method and the material used are discussed. The main symptoms and signs are analyzed and correlated with the failure of the mass transfer process and the accumulation of metabolic residues. The anatomy of binocular vision is analyzed as a part of the forced convection mechanism, and in conclusion, the report shows the main oculomotor functions, topographic mapping of corneas over an interval of 17 months.
{"title":"Analysis of the Disturbances Caused by Intraocular Forced Convection Mechanism Failure","authors":"H. D. Silva, E. D. Silva, Maria do Carmo Tatiana Dória Silva, C. P. Dória, Cristiane Pereira Dória","doi":"10.5772/INTECHOPEN.72248","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.72248","url":null,"abstract":"In this chapter, we show the refractive error treatment result of a patient, the first author, who restarted in 2000, after a 4-year break, at the study start. According to previous pub-lications, the treatment consists of rehydration and elimination of agglutinated, dehy- drated and deposited metabolic residues in the cornea, the trabecular meshwork, the crystalline lens and the retina, as a consequence of the failure in the mechanism of intra- ocular mass transfer by forced convection. However, the forced movement of the metabolic mass to rehydrate one region can cause dehydration in another region. Therefore, the patient developed posterior and capsular cataract in their respective eyes, right and left. This dehydration, during the treatment, increases the difficulties for the success of the treatment. The first part is a chronological record of the most important components of the treatment. Then, the research method and the material used are discussed. The main symptoms and signs are analyzed and correlated with the failure of the mass transfer process and the accumulation of metabolic residues. The anatomy of binocular vision is analyzed as a part of the forced convection mechanism, and in conclusion, the report shows the main oculomotor functions, topographic mapping of corneas over an interval of 17 months.","PeriodicalId":357034,"journal":{"name":"Difficulties in Cataract Surgery","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130374541","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-20DOI: 10.5772/INTECHOPEN.71031
A. Rodríguez-Garcia, C. Foster
Cataract is one of the most frequent visual impairment complications of uveitis, accounting for up to 40% of the visual loss seen in these patients. In general, uveitis patients differ from the general cataract population in that they are younger and have a higher rate of comorbidities, however the rates of inflammatory sequelae vary markedly among uveitic entities. Cataract development may be influenced by the cause and duration of uveitis, the degree of inflammation control, and the use of corticosteroid therapy. Cataract surgery in patients with uveitis represents a serious challenge due to pre-existing ocular comorbidities that may limit the visual outcome and difficult the surgical procedure; the need for preoperative control of inflammation; and the efficacy of postoperative management to avoid immediate and late ocular complications. A detailed ophthalmologic exam prior to surgery is essential to know the status of pre-existing pathologic changes, adjust the medical therapy to achieve absolute control of inflammation, establish a surgical plan, and deliver an objective visual prognosis to the patient or the relatives. The key point to surgical success is the absolute control of inflammation, meaning no cells in the anterior chamber for at least 3 months prior to surgery. Today, minimally invasive phacoemulsification with acrylic foldable intraocular lens implantation is the standard of care for most patients with uveitis. It must be taken into consideration that higher rates of intraoperative and postoperative complications may occur. Vision-limiting pathology related to pre-existing uveitis complications are the major contributing factors for limited postoperative visual outcome.
{"title":"Cataract Surgery in Patients with Uveitis: Preoperative and Surgical Considerations","authors":"A. Rodríguez-Garcia, C. Foster","doi":"10.5772/INTECHOPEN.71031","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.71031","url":null,"abstract":"Cataract is one of the most frequent visual impairment complications of uveitis, accounting for up to 40% of the visual loss seen in these patients. In general, uveitis patients differ from the general cataract population in that they are younger and have a higher rate of comorbidities, however the rates of inflammatory sequelae vary markedly among uveitic entities. Cataract development may be influenced by the cause and duration of uveitis, the degree of inflammation control, and the use of corticosteroid therapy. Cataract surgery in patients with uveitis represents a serious challenge due to pre-existing ocular comorbidities that may limit the visual outcome and difficult the surgical procedure; the need for preoperative control of inflammation; and the efficacy of postoperative management to avoid immediate and late ocular complications. A detailed ophthalmologic exam prior to surgery is essential to know the status of pre-existing pathologic changes, adjust the medical therapy to achieve absolute control of inflammation, establish a surgical plan, and deliver an objective visual prognosis to the patient or the relatives. The key point to surgical success is the absolute control of inflammation, meaning no cells in the anterior chamber for at least 3 months prior to surgery. Today, minimally invasive phacoemulsification with acrylic foldable intraocular lens implantation is the standard of care for most patients with uveitis. It must be taken into consideration that higher rates of intraoperative and postoperative complications may occur. Vision-limiting pathology related to pre-existing uveitis complications are the major contributing factors for limited postoperative visual outcome.","PeriodicalId":357034,"journal":{"name":"Difficulties in Cataract Surgery","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116082453","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2017-12-20DOI: 10.5772/INTECHOPEN.71969
I. Dekaris, N. Gabrić, Ante Barišić, A. Pašalić
Introduction: The first generations of multifocal intraocular lenses (MFIOLs) were designed to provide patients good distance and near vision, but intermediate was not satisfactory. Trifocal, a bifocal of low-add and quadrifocal MFIOLs were invented, offering possibility to correct vision for distance, near, and intermediate tasks. The novel IOL, extended range of vision (EROV), is covering mostly intermediate and distance vision, with lower level of photic phenomena. Patients and methods: We have evaluated visual results in 4408 eyes implanted with different MFIOLs in 12 years period (2004–2016). Postoperative uncorrected visual acuity for far, intermediate, and near was evaluated. Postoperative satisfaction and complica- tion rate and management of complications are presented. Results: In the first generation MFIOLs, almost 70% of eyes gained uncorrected distance visual acuity of 1.0. Uncorrected near visual acuity was J1–J2 in 95% of eyes with diffractive IOLs. Modern MFIOL designs enabled improvement of vision at intermediate dis- tance, without compromising vision at far and near. Conclusion: With the first generations of MFIOLs, good distance and near uncorrected vision was achieved. With novel MFIOLs a very good uncorrected vision was achieved at far, intermediate and near, while with EROV lens, near vision was less satisfactory, but patients had less photic phenomena. IOL is a non-apodized diffractive trifocal IOL with an intermediary 4.5 mm diffractive zone that distributes light to three focal points independent on pupil size. The IOL is a single-piece lens fabricated from a hydrophobic and ultravio-let- and blue light-filtering acrylate/methacrylate copolymer material. This novel diffractive structure has optimized light utilization, transmitting 88% of light at the simulated 3.0 mm pupil size to the retina. The light is split into two, with one half allocated to the distance focus and the other half split evenly between the near and intermediate focuses. The lens design is intended to improve the intermediate vision tasks and increase patient satisfaction, with a third focal point at an optimal intermediate distance of 60 cm, tending to provide more continuous vision. Bifocal diffractive “low-add” IOLs are provided with different add-powers (e.g., +2.75D, +3.25D, +4.00D add), and they have a full diffractive profile on the posterior surface of the optic. The relief height of the diffractive rings is equal in all three models; they have equal light distribution to distance and near regardless of pupil size or add-power. The focal point distance is controlled by the number and spacing of the diffractive rings, and patients have same contrast sensitivity and low-light visual acuity for all add-powers. Extended range of vision IOL delivers a continuous, full-range vision with reduced incidence of halos and glare. It merges two complementary technologies: echelette design which introduces a novel pattern of light diffraction that elongates
{"title":"Presbyopia Correction During Cataract Surgery with Multifocal Intraocular Lenses","authors":"I. Dekaris, N. Gabrić, Ante Barišić, A. Pašalić","doi":"10.5772/INTECHOPEN.71969","DOIUrl":"https://doi.org/10.5772/INTECHOPEN.71969","url":null,"abstract":"Introduction: The first generations of multifocal intraocular lenses (MFIOLs) were designed to provide patients good distance and near vision, but intermediate was not satisfactory. Trifocal, a bifocal of low-add and quadrifocal MFIOLs were invented, offering possibility to correct vision for distance, near, and intermediate tasks. The novel IOL, extended range of vision (EROV), is covering mostly intermediate and distance vision, with lower level of photic phenomena. Patients and methods: We have evaluated visual results in 4408 eyes implanted with different MFIOLs in 12 years period (2004–2016). Postoperative uncorrected visual acuity for far, intermediate, and near was evaluated. Postoperative satisfaction and complica- tion rate and management of complications are presented. Results: In the first generation MFIOLs, almost 70% of eyes gained uncorrected distance visual acuity of 1.0. Uncorrected near visual acuity was J1–J2 in 95% of eyes with diffractive IOLs. Modern MFIOL designs enabled improvement of vision at intermediate dis- tance, without compromising vision at far and near. Conclusion: With the first generations of MFIOLs, good distance and near uncorrected vision was achieved. With novel MFIOLs a very good uncorrected vision was achieved at far, intermediate and near, while with EROV lens, near vision was less satisfactory, but patients had less photic phenomena. IOL is a non-apodized diffractive trifocal IOL with an intermediary 4.5 mm diffractive zone that distributes light to three focal points independent on pupil size. The IOL is a single-piece lens fabricated from a hydrophobic and ultravio-let- and blue light-filtering acrylate/methacrylate copolymer material. This novel diffractive structure has optimized light utilization, transmitting 88% of light at the simulated 3.0 mm pupil size to the retina. The light is split into two, with one half allocated to the distance focus and the other half split evenly between the near and intermediate focuses. The lens design is intended to improve the intermediate vision tasks and increase patient satisfaction, with a third focal point at an optimal intermediate distance of 60 cm, tending to provide more continuous vision. Bifocal diffractive “low-add” IOLs are provided with different add-powers (e.g., +2.75D, +3.25D, +4.00D add), and they have a full diffractive profile on the posterior surface of the optic. The relief height of the diffractive rings is equal in all three models; they have equal light distribution to distance and near regardless of pupil size or add-power. The focal point distance is controlled by the number and spacing of the diffractive rings, and patients have same contrast sensitivity and low-light visual acuity for all add-powers. Extended range of vision IOL delivers a continuous, full-range vision with reduced incidence of halos and glare. It merges two complementary technologies: echelette design which introduces a novel pattern of light diffraction that elongates","PeriodicalId":357034,"journal":{"name":"Difficulties in Cataract Surgery","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-12-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127280883","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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