1) The study examined the relationship between visual acuity and the optics quality, as measured by average modulation, of 3 multifocal IOL models.
2) They found that a difference in average modulation (optics quality) of up to 15% did not produce significant differences in visual acuity, but a difference of 25% or more did produce significant differences.
3) There was a strong linear correlation between IOL optics quality and visual acuity, especially under photopic conditions with a 3.5mm pupil, indicating tolerance to about a 15% decrease in optics quality before impacting visual acuity.
Automated Diagnosis of Glaucoma using Haralick Texture FeaturesIOSR Journals
Abstract : Glaucoma is the second leading cause of blindness worldwide. It is a disease in which fluid
pressure in the eye increases continuously, damaging the optic nerve and causing vision loss. Computational
decision support systems for the early detection of glaucoma can help prevent this complication. The retinal
optic nerve fibre layer can be assessed using optical coherence tomography, scanning laser polarimetry, and
Heidelberg retina tomography scanning methods. In this paper, we present a novel method for glaucoma
detection using an Haralick Texture Features from digital fundus images. K Nearest Neighbors (KNN)
classifiers are used to perform supervised classification. Our results demonstrate that the Haralick Texture
Features has Database and classification parts, in Database the image has been loaded and Gray Level Cooccurrence
Matrix (GLCM) and thirteen haralick features are combined to extract the image features, performs
better than the other classifiers and correctly identifies the glaucoma images with an accuracy of more than
98%. The impact of training and testing is also studied to improve results. Our proposed novel features are
clinically significant and can be used to detect glaucoma accurately.
Keywords: Glaucoma, Haralick Texture features, KNN Classifiers, Feature Extraction
Identification of Focal Cortical Dysplasia (FCD) can be difficult due to the subtle MRI changes. Though sequences like FLAIR (fluid attenuated inversion recovery) can detect a large majority of these lesions, there are smaller lesions without signal changes that can easily go unnoticed by the naked eye. The aim of this study is to improve the visibility of Focal Cortical Dysplasia lesions in the T1 weighted brain MRI images. In the proposed method, we used a complex diffusion based approach for calculating the FCD affected areas.
Retinal Macular Edema Detection Using Optical Coherence Tomography ImagesIOSRJVSP
Macular Edema affects around 20 million people of the world each year. Optical Coherence Tomography (OCT), a non-invasive eye-imaging modality, is capable of detecting Macular Edema both in its early and advanced stages. In this paper, an algorithm which detects Macular Edema from OCT images has been presented. Initially the images are filtered to de-noise them. Then, the retinal layers - Inner Limiting Membrane (ILM) and Retinal Pigment Epithelium (RPE) are segmented using Graph Theory method. Region splitting is performed on the OCT scan and the thickness between the two layers in the different regions are determined. Area enclosed between the two layers is also estimated. Support Vector Machine, a binary classifier is used to draw a classification between normal and abnormal OCT scans. Region-wise thickness, a few Haralick’s features, area between ILM and RPE and a few wavelet features are used to train the classifier. The classifier yielded an accuracy of 95% and a sensitivity of 100%. Thus, this algorithm can be used by ophthalmologists in early detection of Macular Edema.
There are three major complications of diabetes which lead to blindness. They are retinopathy, cataracts, and glaucoma among which diabetic retinopathy is considered as the most serious complication affecting the blood vessels in the retina. Diabetic retinopathy (DR) occurs when tiny vessels swell and leak fluid or abnormal new blood vessels grow hampering normal vision.
Diabetic retinopathy is a widespread problem of visual impairment. The abnormalities like microaneurysms, hemorrhages and exudates are the key symptoms which play an important role in diagnosis of diabetic retinopathy. Early detection of these abnormalities may prevent the blurred vision or vision loss due to diabetic retinopathy. Basically exudates are lipid lesions able to be seen in optical images. Exudates are categorized into hard exudates and soft exudates based on its appearance. Hard exudates come out as intense yellow regions and soft exudates have fuzzy manifestations. Automatic detection of exudates may aid ophthalmologists in diagnosis of diabetic retinopathy and its early treatment. Fig. 1 shows the key symptoms of diabetic retinopathy.
Automated Diagnosis of Glaucoma using Haralick Texture FeaturesIOSR Journals
Abstract : Glaucoma is the second leading cause of blindness worldwide. It is a disease in which fluid
pressure in the eye increases continuously, damaging the optic nerve and causing vision loss. Computational
decision support systems for the early detection of glaucoma can help prevent this complication. The retinal
optic nerve fibre layer can be assessed using optical coherence tomography, scanning laser polarimetry, and
Heidelberg retina tomography scanning methods. In this paper, we present a novel method for glaucoma
detection using an Haralick Texture Features from digital fundus images. K Nearest Neighbors (KNN)
classifiers are used to perform supervised classification. Our results demonstrate that the Haralick Texture
Features has Database and classification parts, in Database the image has been loaded and Gray Level Cooccurrence
Matrix (GLCM) and thirteen haralick features are combined to extract the image features, performs
better than the other classifiers and correctly identifies the glaucoma images with an accuracy of more than
98%. The impact of training and testing is also studied to improve results. Our proposed novel features are
clinically significant and can be used to detect glaucoma accurately.
Keywords: Glaucoma, Haralick Texture features, KNN Classifiers, Feature Extraction
Identification of Focal Cortical Dysplasia (FCD) can be difficult due to the subtle MRI changes. Though sequences like FLAIR (fluid attenuated inversion recovery) can detect a large majority of these lesions, there are smaller lesions without signal changes that can easily go unnoticed by the naked eye. The aim of this study is to improve the visibility of Focal Cortical Dysplasia lesions in the T1 weighted brain MRI images. In the proposed method, we used a complex diffusion based approach for calculating the FCD affected areas.
Retinal Macular Edema Detection Using Optical Coherence Tomography ImagesIOSRJVSP
Macular Edema affects around 20 million people of the world each year. Optical Coherence Tomography (OCT), a non-invasive eye-imaging modality, is capable of detecting Macular Edema both in its early and advanced stages. In this paper, an algorithm which detects Macular Edema from OCT images has been presented. Initially the images are filtered to de-noise them. Then, the retinal layers - Inner Limiting Membrane (ILM) and Retinal Pigment Epithelium (RPE) are segmented using Graph Theory method. Region splitting is performed on the OCT scan and the thickness between the two layers in the different regions are determined. Area enclosed between the two layers is also estimated. Support Vector Machine, a binary classifier is used to draw a classification between normal and abnormal OCT scans. Region-wise thickness, a few Haralick’s features, area between ILM and RPE and a few wavelet features are used to train the classifier. The classifier yielded an accuracy of 95% and a sensitivity of 100%. Thus, this algorithm can be used by ophthalmologists in early detection of Macular Edema.
There are three major complications of diabetes which lead to blindness. They are retinopathy, cataracts, and glaucoma among which diabetic retinopathy is considered as the most serious complication affecting the blood vessels in the retina. Diabetic retinopathy (DR) occurs when tiny vessels swell and leak fluid or abnormal new blood vessels grow hampering normal vision.
Diabetic retinopathy is a widespread problem of visual impairment. The abnormalities like microaneurysms, hemorrhages and exudates are the key symptoms which play an important role in diagnosis of diabetic retinopathy. Early detection of these abnormalities may prevent the blurred vision or vision loss due to diabetic retinopathy. Basically exudates are lipid lesions able to be seen in optical images. Exudates are categorized into hard exudates and soft exudates based on its appearance. Hard exudates come out as intense yellow regions and soft exudates have fuzzy manifestations. Automatic detection of exudates may aid ophthalmologists in diagnosis of diabetic retinopathy and its early treatment. Fig. 1 shows the key symptoms of diabetic retinopathy.
Effective segmentation of sclera, iris and pupil in noisy eye imagesTELKOMNIKA JOURNAL
In today’s sensitive environment, for personal authentication, iris recognition is the most attentive
technique among the various biometric technologies. One of the key steps in the iris recognition system is
the accurate iris segmentation from its surrounding noises including pupil and sclera of a captured
eye-image. In our proposed method, initially input image is preprocessed by using bilateral filtering.
After the preprocessing of images contour based features such as, brightness, color and texture features
are extracted. Then entropy is measured based on the extracted contour based features to effectively
distinguishing the data in the images. Finally, the convolution neural network (CNN) is used for
the effective sclera, iris and pupil parts segmentations based on the entropy measure. The proposed
results are analyzed to demonstrate the better performance of the proposed segmentation method than
the existing methods.
Abstract:
A technique for exudate detectionin fundus image is been presented in this paper. Due to diabetic retinopathy an abnormality is caused known as exudates.The loss of vision can be prevented by detecting the exudates as early as possible. The work mainly aims at detecting exudates which is present in the green channel of the RGB image by applying few preprocessing steps, DWT and feature extraction. The extracted features are fed to 3 different classifiers such as KNN, SVM and NN. Based on the classifier result if an exudate is present the extraction of exudate ROI is done based on canny edge detection followed by morphological operations. The severity of the exudates is established on the area of the detected exudate.
Keywords:Exudates, Fundus image, Diabetic retinopathy, DWT, KNN, SVM, NN, Canny edge detection, Morphological operations.
In this paper, cysts are detected in the ultrasonic images of ovary. PCOS is an endocrine disorder affecting women of reproductive age. This syndrome is mainly seen in women whose age is in between 25 and 35. We are proposing methods for identifying whether a person is suffering from Polycystic Ovary Syndrome (PCOS) or not. Ultrasound imaging of the follicles gives important information about the size, number and mode of arrangement of follicles, position and response to hormonal stimulation. A thresholding function is applied for denoising the image in the wavelet domain. Before the segmentation process the ultrasonic image is preprocessed using contrast enhancement technique. Morphological approach is used for implementing contrast enhancement. This is performed in order to improve the clarity and quality of the image. Fuzzy c-means clustering algorithm is applied to the resultant image. Finally the cysts are detected with the help of clusters. The efficiency of the algorithm depends upon the value of Mean Square Error (MSE) and Peak Signal to Noise Ratio (PSNR).
Fuzzy Clustering Based Segmentation of Vertebrae in T1-Weighted Spinal MR Imagesijfls
Image segmentation in the medical domain is a challenging field owing to poor resolution and limited
contrast. The predominantly used conventional segmentation techniques and the thresholding methods
suffer from limitations because of heavy dependence on user interactions. Uncertainties prevalent in an
image cannot be captured by these techniques. The performance further deteriorates when the images are
corrupted by noise, outliers and other artifacts. The objective of this paper is to develop an effective robust
fuzzy C- means clustering for segmenting vertebral body from magnetic resonance image owing to its
unsupervised form of learning. The motivation for this work is detection of spine geometry and proper
localisation and labelling will enhance the diagnostic output of a physician. The method is compared with
Otsu thresholding and K-means clustering to illustrate the robustness.The reference standard for validation
was the annotated images from the radiologist, and the Dice coefficient and Hausdorff distance measures
were used to evaluate the segmentation
- An article describes what is the impact of refractive error on a layer of retina ( nerve fiber layer) in myopic subjects, Download its full text from Isra Medical Journal.
Objective: To evaluate myopic impact on thickness of nerve fiber layer of the retina in healthy myopic subjects.
Study Design: Prospective Observational study.
Place and Duration: Investigative Department of Ophthalmology of Al-Ibrahim Eye Hospital, Karachi from 1st May 2018 to 30th October 2018.
Methodology: In this study 80 eyes of myopic subjects (SE -0.5 to -11.0 DS) were enrolled. Each eye underwent through comprehensive ocular examination beginning with visual acuity, refraction, fundoscopy by slit lamp and ending up to optical coherence tomography of Nidek. Mean average peripapillary thickness of nerve fiber layer and thickness in superior, inferior, nasal and temporal quadrants was taken into consideration, calculated by Spectral Domain Optical Coherence Tomography (version 1.5.5.0).
Results: Forty subjects volunteered for study protocol among which 21 were male and 19 were female with a degree of refractive breakdown of 30% mild myopic, 50% moderately myopic and 20% highly myopic. The calculated average age was 25.0 ± 5.0 years (range 16-40 years). The average total nerve fiber layer thickness in myopic respondents was 90.85μm; superiorly 112.37μm; inferiorly 117.52μm; temporally 71.85μm and in nasal quadrant was 61.55μm. Retinal nerve fiber layer thickness was statistically significant in superior and temporal quadrant. In high myopes thickness was clinically significant in inferior quadrant in terms of quantity as compared to mild and moderate myopia
Conclusion: Average retinal nerve fiber layer thickness was significantly decreased in high myopia as compared to mild myopia while moderate group had slightly thicker thickness than high myopic group. Hence impact of dioptric power on nerve fiber layer thickness in myopic patients is significant.
Purpose: To evaluate the corneal volume (CV) before and after Ferrara intrastromal corneal ring segments (ICRS) implantation and its influence in clinical outcomes in keratoconus patients.
Effective segmentation of sclera, iris and pupil in noisy eye imagesTELKOMNIKA JOURNAL
In today’s sensitive environment, for personal authentication, iris recognition is the most attentive
technique among the various biometric technologies. One of the key steps in the iris recognition system is
the accurate iris segmentation from its surrounding noises including pupil and sclera of a captured
eye-image. In our proposed method, initially input image is preprocessed by using bilateral filtering.
After the preprocessing of images contour based features such as, brightness, color and texture features
are extracted. Then entropy is measured based on the extracted contour based features to effectively
distinguishing the data in the images. Finally, the convolution neural network (CNN) is used for
the effective sclera, iris and pupil parts segmentations based on the entropy measure. The proposed
results are analyzed to demonstrate the better performance of the proposed segmentation method than
the existing methods.
Abstract:
A technique for exudate detectionin fundus image is been presented in this paper. Due to diabetic retinopathy an abnormality is caused known as exudates.The loss of vision can be prevented by detecting the exudates as early as possible. The work mainly aims at detecting exudates which is present in the green channel of the RGB image by applying few preprocessing steps, DWT and feature extraction. The extracted features are fed to 3 different classifiers such as KNN, SVM and NN. Based on the classifier result if an exudate is present the extraction of exudate ROI is done based on canny edge detection followed by morphological operations. The severity of the exudates is established on the area of the detected exudate.
Keywords:Exudates, Fundus image, Diabetic retinopathy, DWT, KNN, SVM, NN, Canny edge detection, Morphological operations.
In this paper, cysts are detected in the ultrasonic images of ovary. PCOS is an endocrine disorder affecting women of reproductive age. This syndrome is mainly seen in women whose age is in between 25 and 35. We are proposing methods for identifying whether a person is suffering from Polycystic Ovary Syndrome (PCOS) or not. Ultrasound imaging of the follicles gives important information about the size, number and mode of arrangement of follicles, position and response to hormonal stimulation. A thresholding function is applied for denoising the image in the wavelet domain. Before the segmentation process the ultrasonic image is preprocessed using contrast enhancement technique. Morphological approach is used for implementing contrast enhancement. This is performed in order to improve the clarity and quality of the image. Fuzzy c-means clustering algorithm is applied to the resultant image. Finally the cysts are detected with the help of clusters. The efficiency of the algorithm depends upon the value of Mean Square Error (MSE) and Peak Signal to Noise Ratio (PSNR).
Fuzzy Clustering Based Segmentation of Vertebrae in T1-Weighted Spinal MR Imagesijfls
Image segmentation in the medical domain is a challenging field owing to poor resolution and limited
contrast. The predominantly used conventional segmentation techniques and the thresholding methods
suffer from limitations because of heavy dependence on user interactions. Uncertainties prevalent in an
image cannot be captured by these techniques. The performance further deteriorates when the images are
corrupted by noise, outliers and other artifacts. The objective of this paper is to develop an effective robust
fuzzy C- means clustering for segmenting vertebral body from magnetic resonance image owing to its
unsupervised form of learning. The motivation for this work is detection of spine geometry and proper
localisation and labelling will enhance the diagnostic output of a physician. The method is compared with
Otsu thresholding and K-means clustering to illustrate the robustness.The reference standard for validation
was the annotated images from the radiologist, and the Dice coefficient and Hausdorff distance measures
were used to evaluate the segmentation
- An article describes what is the impact of refractive error on a layer of retina ( nerve fiber layer) in myopic subjects, Download its full text from Isra Medical Journal.
Objective: To evaluate myopic impact on thickness of nerve fiber layer of the retina in healthy myopic subjects.
Study Design: Prospective Observational study.
Place and Duration: Investigative Department of Ophthalmology of Al-Ibrahim Eye Hospital, Karachi from 1st May 2018 to 30th October 2018.
Methodology: In this study 80 eyes of myopic subjects (SE -0.5 to -11.0 DS) were enrolled. Each eye underwent through comprehensive ocular examination beginning with visual acuity, refraction, fundoscopy by slit lamp and ending up to optical coherence tomography of Nidek. Mean average peripapillary thickness of nerve fiber layer and thickness in superior, inferior, nasal and temporal quadrants was taken into consideration, calculated by Spectral Domain Optical Coherence Tomography (version 1.5.5.0).
Results: Forty subjects volunteered for study protocol among which 21 were male and 19 were female with a degree of refractive breakdown of 30% mild myopic, 50% moderately myopic and 20% highly myopic. The calculated average age was 25.0 ± 5.0 years (range 16-40 years). The average total nerve fiber layer thickness in myopic respondents was 90.85μm; superiorly 112.37μm; inferiorly 117.52μm; temporally 71.85μm and in nasal quadrant was 61.55μm. Retinal nerve fiber layer thickness was statistically significant in superior and temporal quadrant. In high myopes thickness was clinically significant in inferior quadrant in terms of quantity as compared to mild and moderate myopia
Conclusion: Average retinal nerve fiber layer thickness was significantly decreased in high myopia as compared to mild myopia while moderate group had slightly thicker thickness than high myopic group. Hence impact of dioptric power on nerve fiber layer thickness in myopic patients is significant.
Purpose: To evaluate the corneal volume (CV) before and after Ferrara intrastromal corneal ring segments (ICRS) implantation and its influence in clinical outcomes in keratoconus patients.
Automatic eye fixations identification based on analysis of variance and cova...Giuseppe Fineschi
Eye movement is the simplest and repetitive movement that enables humans to interact with the environment. The common daily activities, such as reading a book or watching television, involve this natural
activity, which consists of rapidly shifting our gaze from one region to another. In clinical application, the
identification of the main components of eye movement during visual exploration, such as fixations and
saccades, is the objective of the analysis of eye movements: however, in patients affected by motor control disorder the identification of fixation is not banal. This work presents a new fixation identification
algorithm based on the analysis of variance and covariance: the main idea was to use bivariate statistical
analysis to compare variance overxandyto identify fixation. We describe the new algorithm, and we
compare it with the common fixations algorithm based on dispersion. To demonstrate the performance
of our approach, we tested the algorithm in a group of healthy subjects and patients affected by motor
control disorder
Comparative Study of Visual Outcome between Femtosecond Lasik with Excimer La...iosrjce
IOSR Journal of Dental and Medical Sciences is one of the speciality Journal in Dental Science and Medical Science published by International Organization of Scientific Research (IOSR). The Journal publishes papers of the highest scientific merit and widest possible scope work in all areas related to medical and dental science. The Journal welcome review articles, leading medical and clinical research articles, technical notes, case reports and others.
Iris Publishers - journal of ophthalmology | Demystifying Role of Ultrasound ...IrisPublishers
Objectives: The aim of this study was to compare sonoelastographic findings in the retina– choroid–sclera (RCS) complex and vitreous in glaucomatous and healthy eyes.Methods: For this cross-sectional comparative study, 20 patients with primary open-angle glaucoma (POAG) and 20 healthy volunteers were recruited. Ultrasound elastography measurements were taken with a sonographic scanner of the RCS complex, anterior vitreous (AV), posterior vitreous (PV), retrobulbar fat tissue (RFT), optic disc, and optic nerve in each eye.Results: The elasticity index of the RCS complex, RFT, optic disc, optic nerve, AV, and PV were similar in both groups (p > 0.05), though the AV/PV strain ratio in the group of patients with glaucoma was significantly higher (p = 0.04).Conclusion: Glaucoma increases the AV/PV strain ratio. In providing reproducible and consistent values, the real-time elastography technique may be helpful in elucidating the mechanisms of glaucoma in some aspects.
Recomendações da OMS sobre cuidados maternos e neonatais para uma experiência pós-natal positiva.
Em consonância com os ODS – Objetivos do Desenvolvimento Sustentável e a Estratégia Global para a Saúde das Mulheres, Crianças e Adolescentes, e aplicando uma abordagem baseada nos direitos humanos, os esforços de cuidados pós-natais devem expandir-se para além da cobertura e da simples sobrevivência, de modo a incluir cuidados de qualidade.
Estas diretrizes visam melhorar a qualidade dos cuidados pós-natais essenciais e de rotina prestados às mulheres e aos recém-nascidos, com o objetivo final de melhorar a saúde e o bem-estar materno e neonatal.
Uma “experiência pós-natal positiva” é um resultado importante para todas as mulheres que dão à luz e para os seus recém-nascidos, estabelecendo as bases para a melhoria da saúde e do bem-estar a curto e longo prazo. Uma experiência pós-natal positiva é definida como aquela em que as mulheres, pessoas que gestam, os recém-nascidos, os casais, os pais, os cuidadores e as famílias recebem informação consistente, garantia e apoio de profissionais de saúde motivados; e onde um sistema de saúde flexível e com recursos reconheça as necessidades das mulheres e dos bebês e respeite o seu contexto cultural.
Estas diretrizes consolidadas apresentam algumas recomendações novas e já bem fundamentadas sobre cuidados pós-natais de rotina para mulheres e neonatos que recebem cuidados no pós-parto em unidades de saúde ou na comunidade, independentemente dos recursos disponíveis.
É fornecido um conjunto abrangente de recomendações para cuidados durante o período puerperal, com ênfase nos cuidados essenciais que todas as mulheres e recém-nascidos devem receber, e com a devida atenção à qualidade dos cuidados; isto é, a entrega e a experiência do cuidado recebido. Estas diretrizes atualizam e ampliam as recomendações da OMS de 2014 sobre cuidados pós-natais da mãe e do recém-nascido e complementam as atuais diretrizes da OMS sobre a gestão de complicações pós-natais.
O estabelecimento da amamentação e o manejo das principais intercorrências é contemplada.
Recomendamos muito.
Vamos discutir essas recomendações no nosso curso de pós-graduação em Aleitamento no Instituto Ciclos.
Esta publicação só está disponível em inglês até o momento.
Prof. Marcus Renato de Carvalho
www.agostodourado.com
The prostate is an exocrine gland of the male mammalian reproductive system
It is a walnut-sized gland that forms part of the male reproductive system and is located in front of the rectum and just below the urinary bladder
Function is to store and secrete a clear, slightly alkaline fluid that constitutes 10-30% of the volume of the seminal fluid that along with the spermatozoa, constitutes semen
A healthy human prostate measures (4cm-vertical, by 3cm-horizontal, 2cm ant-post ).
It surrounds the urethra just below the urinary bladder. It has anterior, median, posterior and two lateral lobes
It’s work is regulated by androgens which are responsible for male sex characteristics
Generalised disease of the prostate due to hormonal derangement which leads to non malignant enlargement of the gland (increase in the number of epithelial cells and stromal tissue)to cause compression of the urethra leading to symptoms (LUTS
Pulmonary Thromboembolism - etilogy, types, medical- Surgical and nursing man...VarunMahajani
Disruption of blood supply to lung alveoli due to blockage of one or more pulmonary blood vessels is called as Pulmonary thromboembolism. In this presentation we will discuss its causes, types and its management in depth.
Report Back from SGO 2024: What’s the Latest in Cervical Cancer?bkling
Are you curious about what’s new in cervical cancer research or unsure what the findings mean? Join Dr. Emily Ko, a gynecologic oncologist at Penn Medicine, to learn about the latest updates from the Society of Gynecologic Oncology (SGO) 2024 Annual Meeting on Women’s Cancer. Dr. Ko will discuss what the research presented at the conference means for you and answer your questions about the new developments.
New Drug Discovery and Development .....NEHA GUPTA
The "New Drug Discovery and Development" process involves the identification, design, testing, and manufacturing of novel pharmaceutical compounds with the aim of introducing new and improved treatments for various medical conditions. This comprehensive endeavor encompasses various stages, including target identification, preclinical studies, clinical trials, regulatory approval, and post-market surveillance. It involves multidisciplinary collaboration among scientists, researchers, clinicians, regulatory experts, and pharmaceutical companies to bring innovative therapies to market and address unmet medical needs.
Flu Vaccine Alert in Bangalore Karnatakaaddon Scans
As flu season approaches, health officials in Bangalore, Karnataka, are urging residents to get their flu vaccinations. The seasonal flu, while common, can lead to severe health complications, particularly for vulnerable populations such as young children, the elderly, and those with underlying health conditions.
Dr. Vidisha Kumari, a leading epidemiologist in Bangalore, emphasizes the importance of getting vaccinated. "The flu vaccine is our best defense against the influenza virus. It not only protects individuals but also helps prevent the spread of the virus in our communities," he says.
This year, the flu season is expected to coincide with a potential increase in other respiratory illnesses. The Karnataka Health Department has launched an awareness campaign highlighting the significance of flu vaccinations. They have set up multiple vaccination centers across Bangalore, making it convenient for residents to receive their shots.
To encourage widespread vaccination, the government is also collaborating with local schools, workplaces, and community centers to facilitate vaccination drives. Special attention is being given to ensuring that the vaccine is accessible to all, including marginalized communities who may have limited access to healthcare.
Residents are reminded that the flu vaccine is safe and effective. Common side effects are mild and may include soreness at the injection site, mild fever, or muscle aches. These side effects are generally short-lived and far less severe than the flu itself.
Healthcare providers are also stressing the importance of continuing COVID-19 precautions. Wearing masks, practicing good hand hygiene, and maintaining social distancing are still crucial, especially in crowded places.
Protect yourself and your loved ones by getting vaccinated. Together, we can help keep Bangalore healthy and safe this flu season. For more information on vaccination centers and schedules, residents can visit the Karnataka Health Department’s official website or follow their social media pages.
Stay informed, stay safe, and get your flu shot today!
Tom Selleck Health: A Comprehensive Look at the Iconic Actor’s Wellness Journeygreendigital
Tom Selleck, an enduring figure in Hollywood. has captivated audiences for decades with his rugged charm, iconic moustache. and memorable roles in television and film. From his breakout role as Thomas Magnum in Magnum P.I. to his current portrayal of Frank Reagan in Blue Bloods. Selleck's career has spanned over 50 years. But beyond his professional achievements. fans have often been curious about Tom Selleck Health. especially as he has aged in the public eye.
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Introduction
Many have been interested in Tom Selleck health. not only because of his enduring presence on screen but also because of the challenges. and lifestyle choices he has faced and made over the years. This article delves into the various aspects of Tom Selleck health. exploring his fitness regimen, diet, mental health. and the challenges he has encountered as he ages. We'll look at how he maintains his well-being. the health issues he has faced, and his approach to ageing .
Early Life and Career
Childhood and Athletic Beginnings
Tom Selleck was born on January 29, 1945, in Detroit, Michigan, and grew up in Sherman Oaks, California. From an early age, he was involved in sports, particularly basketball. which played a significant role in his physical development. His athletic pursuits continued into college. where he attended the University of Southern California (USC) on a basketball scholarship. This early involvement in sports laid a strong foundation for his physical health and disciplined lifestyle.
Transition to Acting
Selleck's transition from an athlete to an actor came with its physical demands. His first significant role in "Magnum P.I." required him to perform various stunts and maintain a fit appearance. This role, which he played from 1980 to 1988. necessitated a rigorous fitness routine to meet the show's demands. setting the stage for his long-term commitment to health and wellness.
Fitness Regimen
Workout Routine
Tom Selleck health and fitness regimen has evolved. adapting to his changing roles and age. During his "Magnum, P.I." days. Selleck's workouts were intense and focused on building and maintaining muscle mass. His routine included weightlifting, cardiovascular exercises. and specific training for the stunts he performed on the show.
Selleck adjusted his fitness routine as he aged to suit his body's needs. Today, his workouts focus on maintaining flexibility, strength, and cardiovascular health. He incorporates low-impact exercises such as swimming, walking, and light weightlifting. This balanced approach helps him stay fit without putting undue strain on his joints and muscles.
Importance of Flexibility and Mobility
In recent years, Selleck has emphasized the importance of flexibility and mobility in his fitness regimen. Understanding the natural decline in muscle mass and joint flexibility with age. he includes stretching and yoga in his routine. These practices help prevent injuries, improve posture, and maintain mobilit
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ARTIFICIAL INTELLIGENCE IN HEALTHCARE.pdfAnujkumaranit
Artificial intelligence (AI) refers to the simulation of human intelligence processes by machines, especially computer systems. It encompasses tasks such as learning, reasoning, problem-solving, perception, and language understanding. AI technologies are revolutionizing various fields, from healthcare to finance, by enabling machines to perform tasks that typically require human intelligence.
Couples presenting to the infertility clinic- Do they really have infertility...Sujoy Dasgupta
Dr Sujoy Dasgupta presented the study on "Couples presenting to the infertility clinic- Do they really have infertility? – The unexplored stories of non-consummation" in the 13th Congress of the Asia Pacific Initiative on Reproduction (ASPIRE 2024) at Manila on 24 May, 2024.
Pharynx and Clinical Correlations BY Dr.Rabia Inam Gandapore.pptx
Etude sur l'acuité visuelle
1. ARTICLE
Correlation between optics quality of multifocal
intraocular lenses and visual acuity
Tolerance to modulation transfer function decay
Adelina Felipe, PhD, Francisco Pastor, MD, PhD, Jose M. Artigas, PhD, Amparo Diez-Ajenjo, OD, MSc,
´
Andres Gene, OD, MSc, Jose L. Menezo, MD, PhD, FEBO
´ ´ ´
PURPOSE: To study the relationship between the optics quality of multifocal intraocular lenses
(IOLs) and distance-corrected near, intermediate, and distance visual acuity to determine the
degree to which optics quality must change to produce a significant difference in visual acuity.
´ ´ ´
SETTING: Fundacion Oftalmologica del Mediterraneo, Valencia, Spain.
METHODS: Monocular distance-corrected visual acuity (decimal and logMAR) was measured at
4 m, 70 cm, and 30 cm under photopic and mesopic conditions in eyes with 1 of 3 multifocal
IOL models. Visual acuity versus the ‘‘average modulation’’ of the IOL was assessed.
RESULTS: The pupil diameter and patient age were similar between the 3 IOL groups (20 eyes
each). A difference in average modulation (ie, optics quality) up to 15% did not produce significant
differences in mean visual acuity between 2 groups; however, there was a significant difference in
mean visual acuity between 2 groups when the average modulation values differed by at least 25%.
The slope of the linear correlation between visual acuity and average modulation was 0.018 (r2 Z
0.91) under photopic conditions and 0.024 (r2 Z 0.089) under mesopic conditions.
CONCLUSIONS: There was a strong linear correlation between IOL optics quality and visual acuity
with distance correction under photopic conditions with a pupil of approximately 3.5 mm in a cohort
in which the patient age was controlled. The correlation was similar under mesopic conditions. The
eye’s tolerance to modulation transfer function decay was approximately 15% of the average mod-
ulation value.
Financial Disclosure: No author has a financial or proprietary interest in any material or method
mentioned.
J Cataract Refract Surg 2010; 36:557–562 Q 2010 ASCRS and ESCRS
In recent years, many clinical and technology-related device.19 When an optics system is perfect (free from
cataract surgery studies have sought to improve the op- aberrations), the MTF function has a characteristic tri-
tics quality of intraocular lenses (IOLs) and to develop angular shape. The modulation value is 1 at a spatial
new IOL designs to improve performance. Advances frequency of zero; the value decreases with the spatial
include pseudoaccommodation,1–5 astigmatism correc- frequency until it reaches the cutoff frequency for
tion,6 and phakic IOLs (pIOLs) for correction of high a particular pupil diameter. The shape of the MTF is al-
ametropia.7–9 Numerous studies in the literature report tered as a result of the aberration effect when the pupil
a reduction in aberration by surgical techniques such size increases or when an IOL is decentered or tilted,
as refractive surgery10–13 and by implantation of con- which decreases the modulation value. In general,
ventional and other IOLs to correct ametropia.14–18 any loss in optics quality affects the shape and value
Thus, it is important to develop IOLs with optimized of the MTF.15,20–22
optics to improve patients’ comfort and visual quality. Moreover, the MTF is the Fourier transform of the
The modulation transfer function (MTF) is used in point-spread function (PSF); a Fourier transform
physical optics as the most suitable parameter for eval- changes a spatial coordinate space into a frequency
uating the optics quality of any optics element or space or vice versa. Although the same information
Q 2010 ASCRS and ESCRS 0886-3350/10/$dsee front matter 557
Published by Elsevier Inc. doi:10.1016/j.jcrs.2009.10.046
2. 558 CORRELATION BETWEEN MULTIFOCAL IOL OPTICS QUALITY AND VISUAL ACUITY
Z 100
can be obtained from the MTF and the PSF, the latter is 1
defined in the ordinary coordinate space rather than in VmZ MTFðf Þ Â df
100 0
the spatial frequency space, and for this reason, it is
easier to understand the PSF. In the PSF, if a system where f is the spatial frequency and df is the differen-
were perfect, the image of a point would be a point; be- tial of the variable f. Thus, the ratio between the 2 pa-
cause the optics elements or lenses are not usually per- rameters is a constant (Average modulation [from
fect, the point is imaged as a spread point. The PSF of 0 to 100] Z 1/100 Area [from 0 to 100]) and the corre-
an optics system shows the exact shape of the image lation holds using a parameter that is proportional to
point formed by the system; the narrower the PSF, the parameter.
the wider the MTF (more frequencies in the image; The frequency 100 cycles per millimeter (c/mm) is
each frequency having good contrast if its modulation approximately equivalent to 30 cycles per degree
value is high) and the better the image quality.23 Given (cpd) and is equal to the unit of decimal visual acuity.
that any object or picture is imaged by the system Moreover, human contrast sensitivity has a maximum
point by point, if the PSF is wide, every point in the im- value at approximately 2 to 8 cpd, which shows the
age will be defocused. importance to vision of the low and middle frequen-
It is possible, therefore, to compare the optics quality cies. Therefore, in this study we considered all fre-
of IOLs by measuring and comparing their MTFs. To quencies from 0 to 100 c/mm (ie, approximately 0 to
simplify the comparison, we used the ‘‘average modu- 30 cpd).
lation’’ value in previous studies.22 This is the value of Nevertheless, knowing there is a difference in the
modulation averaged in the range of frequencies from MTF between 2 IOLs is not enough to determine
0 to 100. In this way, each MTF is represented by only whether a patient would appreciate a difference in vi-
a numeric value (average modulation). The area under sual quality with 1 IOL or the other. For example, Ar-
the MTF curve has been used in studies of the quality tigas et al.9 found differences from 10% to 14% in
of different optics elements, such as lenses and contact modulation values between 2 pIOLs but found no sig-
lenses.24 Nevertheless, studies published in the past nificant difference in the visual response between the 2
few years9,22 used average modulation instead of the IOLs.25 The question is how much the average modu-
area under the curve because the information pro- lation of an IOL must change to cause a significant dif-
vided by both parameters (area under the MTF and av- ference in visual acuity. In this study, we attempted to
erage modulation) is of equal value and almost answer that question. We measured the monocular
equivalent. Moreover, it is easier to obtain and under- distance, near, and intermediate visual acuities after
stand average modulation because the value is in- cataract surgery in patients with 1 of 3 models of mul-
cluded in recently released devices for measuring tifocal IOLs. Nine MTFs (3 IOLs with 3 focuses) sum-
MTF.21,22 It is easily proved that the 2 parameters are marized by 9 average modulation values and 9
proportional. The area under the MTF is 100 times visual acuity values (3 IOLs evaluated at 3 distances)
the value of average modulation under the conditions were available to calculate a linear regression between
used in our study, as follows: the 2 variables. In our study, it was necessary to limit
the age range and pupil size as much as possible to iso-
Z 100
late the influence of average modulation on visual acu-
AreaZ MTFðf Þ Â df ity from the effect of other parameters.
0
with the mean value
PATIENTS AND METHODS
This retrospective nonrandomized study evaluated 1 eye of
patients having cataract surgery with implantation of 1 of
3 multifocal IOL models. Inclusion criteria were cataract in
both eyes, corneal astigmatism less than 1.00 diopter (D), po-
Submitted: July 2, 2009. tential postoperative photopic acuity better than 0.6 decimal
Final revision submitted: October 20, 2009. (0.20 logMAR), signed informed consent, IOL power of
Accepted: October 22, 2009. 21.00 D G 3.00 (SD), age between 65 years and 70 years,
and photopic pupil diameter between 3.2 mm and 4.0 mm.
´ ´ ´
From the Fundacion Oftalmologica del Mediterraneo (Felipe, Pastor, Exclusion criteria were previous refractive or glaucoma
´
Artigas, Diez-Ajeno, Menezo) and Departamento de Optica (Felipe, surgery, degenerative optical disease, and disease that could
´
Artigas), Facultad de Fısica, Universitat de Valencia, Burjassot affect the final results.
(Valencia), Spain.
´
Corresponding author: Adelina Felipe, PhD, Departamento de Opti- Multifocal Intraocular Lenses
´
ca, Facultad de Fısica, Universidad de Valencia, C/Dr Moliner, 50, Eyes in the acrylic refractive–diffractive group received an
E46100-Burjassot (Valencia), Spain. E-mail: adelina.felipe@uv.es. AcrySof ReSTOR SN60D3 IOL (Alcon, Inc.). This acrylic
J CATARACT REFRACT SURG - VOL 36, APRIL 2010
3. CORRELATION BETWEEN MULTIFOCAL IOL OPTICS QUALITY AND VISUAL ACUITY 559
refractive–diffractive monoblock IOL has a biconvex optic, Early Treatment Diabetic Retinopathy Study chart at 4 m.
square edges, and a yellow filter to protect the macula in Each letter on the chart that is read correctly adds 0.02 log-
the blue zone of the solar spectrum. The optic design is MAR units to the visual acuity. All visual acuity mea-
refractive at the periphery for distance vision and apodized surements were performed under photopic (85 candelas
diffractive at the central 3.6 mm portion of the anterior [cd]/m2) and mesopic (3 cd/m2) conditions. Visual acuity re-
surface for distance and near vision. The diffractive steps sults are presented in logMAR and decimal values.
are greater in the center of the optic to give a greater propor- Visual acuity values 3 months after surgery was used in
tion to near vision. this study because the visual response is relatively stable
Eyes in the acrylic refractive group received a ReZoom by this time.14 Corrected distance visual acuity was measured
NXG IOL (Abbott Medical Optics, Inc.). This acrylic refrac- at 4 m (vergence À0.25 D), near visual acuity at 33 cm (ver-
tive IOL has 3 biconvex optic components with a triple- gence À3.00 D), and intermediate acuity at 70 cm (vergence
edge design to minimize optical phenomena and capsule À1.50 D), the approximate distance for working in front of
opacification. The optic has 5 concentric rings; the 3 rings a computer monitor.
with odd numbers are for distance vision and rings 2 and 4
are for near vision. The IOL has an addition (add) of 3.50 D
and an aspheric transition between zones for intermediate Statistical Analysis
vision. Statistical analysis was performed by means of the Stu-
Eyes in the silicone refractive–diffractive group received dent t test analysis of variance. A P value less than 0.05
a Tecnis ZM900 (Abbott Medical Optics, Inc.). This 3-piece was considered statistically significant.
silicone IOL has a biconvex optic with refractive–diffractive
characteristics because both optic systems are used simulta-
neously. The refractive zone is on the anterior surface and is RESULTS
for distance focus. The diffractive zone comprises 32 concen- This study comprised 60 eyes, 20 in each IOL group.
tric rings on the posterior surface and provides near focus.
The add is 4.00 D. The edges are square, and the anterior sur-
The mean age of the patients was 67.9 G 1.6 years
face is prolate to compensate for spherical aberration. and the mean pupil diameter, 3.5 G 0.4 mm under
photopic conditions and 5.4 G 0.7 mm under mesopic
Patient Assessment conditions. There was no statistically significant differ-
ence between IOL groups in age or pupil diameter.
Before surgery, patients had a full ophthalmologic exam-
ination including manifest refraction, corrected distance vi- Table 1 shows the mean modulation values for each
sual acuity, keratometry, slitlamp biomicroscopy, corneal IOL for distance, near, and intermediate vision and the
endothelial cell count, and Goldmann applanation tonome- relative difference between the values. The relative dif-
try. Binocular indirect ophthalmoscopy was performed ference represents the difference in optics quality.
through a dilated pupil when needed. Axial length (AL) Table 2 shows the monocular visual acuity by IOL
and anterior segment size were measured by optical coher-
ence biometry (IOLMaster, Carl Zeiss Meditec). Topography group. Under photopic conditions, there were no sta-
was assessed using a Scheimpflug scanning-slit system (Pen- tistically significant differences in acuity between the
tacam, Oculus) to monitor possible postoperative changes in 2 acrylic IOL groups at any distance; however, the dif-
corneal shape that could cause misinterpretation of the re- ferences between the silicone IOL group and each of
sults; these data were used only to avoid false differences be- the 2 acrylic IOL groups were statistically significant
tween IOLs. Postoperative assessments were performed at 1
day, 1 week, and 1 and 3 months. at all distances. The results were the same under mes-
The MTF was calculated from the cross line–spread func- opic conditions except that differences between the sil-
tion recorded with an Opal Vector System (Image Science, icone IOL group and each of the 2 acrylic IOL groups
Ltd.) using fast Fourier transform techniques. The device were statistically significant only at distance and near.
and details about the technique have been described.22 The Figure 1 shows the linear regression of the 9 phot-
MTF measurements were performed using an artificial eye
model that included an artificial cornea and a wet cell con- opic visual acuity values compared with the 9 average
taining physiological solution, where the IOL was modulation values obtained with a 3.5 mm pupil.
positioned. Figure 2 shows the linear regression for visual acuity
and average modulation mesopic values with 5.5 mm
Surgical Technique pupils.
All cataract surgeries were performed by the same experi-
enced surgeon (F.P) using topical anesthesia. Standard pha- DISCUSSION
coemulsification was performed through a 2.75 mm clear
corneal incision. After irrigation and aspiration of the cortex, Our study found no statistically significant differences
the IOL was implanted in the capsular bag using the injector between the 2 acrylic multifocal IOLs at any distance,
developed for the specific IOL. Postoperatively, patients which agrees with the results in other studies.26–29
used tobramycin–dexamethasone for 4 weeks. Nevertheless, Chang30 found a significant difference
in near vision between the 2 IOLs. The ReZoom
Visual Acuity Measurements NXG is the only refractive IOL of the 3 IOL models
Monocular logMAR visual acuity was measured with dis- studied. This explains why the MTF and visual acuity
tance refractive correction with nondilated pupils using an with this IOL were significantly different from those of
J CATARACT REFRACT SURG - VOL 36, APRIL 2010
4. 560 CORRELATION BETWEEN MULTIFOCAL IOL OPTICS QUALITY AND VISUAL ACUITY
Table 1. Average modulation values* and the relative difference between the values.
Intraocular Lens
Acrylic Refractive–Diffractive Acrylic Refractive Silicone Refractive–Diffractive Acrylic Refractive–Diffractive
Parameter AM Diff (%) AM Diff (%) AM Diff (%) AM
3.5 mm pupil
Distance 40 15 46 48 31 29 40
Near 27 4 28 29 36 33 27
Intermediate 20 11 18 39 25 25 20
5.5 mm pupil
Distance 36 6 38 41 27 33 36
Near 24 4 25 28 32 33 24
Intermediate 16 6 17 14 18 13 16
AM Z average modulation; Diff Z relative difference between the average modulation values on either side
*Obtained from MTF measured with 3.5 mm pupil based on mean photopic diameter of 3.5 G 0.4 mm and with 5.5 mm pupils based on mean mesopic diameter
of 5.4 G 0.7 mm
the other 2 IOLs, as reported in a comparative techni- difference had differences of 25% or over. We per-
cal study between refractive and diffractive multifocal formed a statistical analysis and found that a decrease
IOLs.22 in the average modulation value of 25% or 24% is
In all cases in which no significant difference was enough to cause a significant decrease in visual acuity
found, the difference in average modulation values with a statistical error of 0.03 and 0.05, respectively;
was 15% or lower; all cases with a significant this error increases to 0.08 and 0.10 when the decrease
Table 2. Monocular visual acuity with best distance correction.
Intraocular Lens
Acrylic Refractive–Diffractive Acrylic Refractive Silicone Refractive–Diffractive Acrylic Refractive–Diffractive
Mean G SD P Value* Mean G SD P Value† Mean G SD P Valuez Mean G SD
Photopic (85 cd/m2)
Distance .30 .001 .001
Decimal 0.96 G 0.11 0.99 G 0.11 0.84 G 0.09 0.96 G 0.11
LogMAR 0.022 G 0.04 0.006 G 0.044 0.080 G 0.045 0.022 G 0.046
Near .45 .013 .001
Decimal 0.78 G 0.09 0.80 G 0.10 0.88 G 0.09 0.78 G 0.09
LogMAR 0.110 G 0.050 0.099 G 0.055 0.058 G 0.045 0.110 G 0.050
Intermediate .33 .001 .002
Decimal 0.54 G 0.09 0.51 G 0.07 0.64 G 0.10 0.54 G 0.09
LogMAR 0.275 G 0.068 0.294 G 0.058 0.201 G 0.071 0.275 G 0.068
Mesopic (3 cd/m2)
Distance .11 .001 .001
Decimal 0.80 G 0.11 0.85 G 0.12 0.65 G 0.10 0.80 G 0.11
LogMAR 0.103 G 0.059 0.074 G 0.060 0.189 G 0.066 0.103 G 0.059
Near .51 .021 .003
Decimal 0.68 G 0.10 0.70 G 0.11 0.78 G 0.10 0.68 G 0.10
LogMAR 0.174 G 0.063 0.161 G 0.067 0.112 G 0.057 0.174 G 0.063
Intermediate .78 .46 .63
Decimal 0.34 G 0.06 0.34 G 0.06 0.35 G 0.07 0.34 G 0.06
LogMAR 0.470 G 0.079 0.478 G 0.082 0.459 G 0.084 0.470 G 0.079
*Between acrylic refractive–diffractive IOL and acrylic refractive IOL
†
Between acrylic refractive IOL and silicone refractive–diffractive IOL
z
Between silicone refractive–diffractive IOL and acrylic refractive–diffractive IOL
J CATARACT REFRACT SURG - VOL 36, APRIL 2010
5. CORRELATION BETWEEN MULTIFOCAL IOL OPTICS QUALITY AND VISUAL ACUITY 561
acuity. According to our results and statistical calcula-
tions, with a 25% decrease in the average modulation
value, the difference in visual acuity is highly signifi-
cant; this suggests that an approximate 20% difference
in average modulation could be enough to produce
a significant difference in visual acuity (with 0.13 sta-
tistical error). Thus, visual quality impairment begins
with a 20% to 25% decrease in the average modulation
value. It is not realistic to establish a more specific
value because we focused on statistical variables and
the specific limit would depend on factors such as
IOL properties, the individual eye, and the viewing
distance.
Figure 1. Mean visual acuity at distance, near, and intermediate un-
der photopic conditions versus the average modulation of the IOL
Although it was not the main objective of this study
(3.5 mm pupil diameter). to find differences between the IOLs, we did find some
difference. Our results were obtained using specific ex-
is 23% and 22%, respectively. We conclude from these perimental conditions; the results might be different if
results that when the MTF of an IOL decreases, in par- the pupil diameter and patient age ranges were
ticular when the average modulation value decreases changed. We were more interested in determining
by 15%, the patient’s visual acuity will probably not whether there is a correlation between IOL optics
be affected. Fortunately, the visual system has a level and visual properties. We found a correlation between
of tolerance to defocus.31 This conclusion could be ap- the optics quality of the IOL, represented by the aver-
plied to studies of factors such as IOL tilt, IOL decen- age modulation parameter, and the patient’s visual
tration off-center, and aberrations because knowing quality, represented by the visual acuity. The slope
the amount of MTF decrease these factors induce of the fitted regression line for photopic vision was
makes it possible to predict the approximate effect 0.18 decimal visual acuity units/10 average modula-
on the patient’s visual outcomes. Pepose1 lists factors tion units and the r2 value was 0.91. This means that
that cannot be determined reliably before cataract sur- 91% of the variability in the visual acuity values was
gery but can affect the performance of multifocal IOLs. the result of the variation in the average modulation
These include the final effective lens position, IOL cen- parameter. The linear regression of visual acuity ver-
tration with regard to the pupil and visual axis, IOL sus average modulation for mesopic vision had a slope
tilt, residual refractive error, and surgically induced of 0.24 decimal visual acuity/10 average modulation
changes in astigmatism or higher-order corneal aber- units; however, the correlation was lower than for
rations. Our results show that if these factors change photopic vision (r2 Z 0.89). In short, the visual acuity
the MTF by less than 15% of the average modulation varied 0.18 decimal units per 10 units of average mod-
value, the effect on visual acuity would likely be ulation variation under photopic conditions and 0.24
negligible. decimal units per 10 units of average modulation var-
Another aspect is to what degree optics quality must iation under mesopic vision.
change to produce a significant difference in visual The AcrySof ReSTOR SN60D3 IOL we used is not
the currently available model. The current model
(SN6AD3) has aspheric optics rather than the spherical
optics of the model used in our study. Although this
difference would likely influence the MTF level, this
was not of primary importance in our study because
we did not compare the quality between the different
IOLs. We simply wanted to have 9 quality values to as-
sess the correlation between visual acuity and average
modulation. We did not provide MTF graphs here be-
cause similar ones have been published.22
In conclusion, the optics quality of IOLs is a decisive
factor in visual performance. Although small varia-
tions in optics quality may go unnoticed by the patient,
Figure 2. Mean visual acuity at distance, near, and intermediate un-
a difference in the MTF that produces a 25% change in
der mesopic conditions versus the average modulation of the IOL the average modulation value will significantly affect
(5.5 mm pupil diameter). the patient’s visual acuity.
J CATARACT REFRACT SURG - VOL 36, APRIL 2010
6. 562 CORRELATION BETWEEN MULTIFOCAL IOL OPTICS QUALITY AND VISUAL ACUITY
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