Background The problem of access to medical information, particularly in low-income countries, ha... more Background The problem of access to medical information, particularly in low-income countries, has been under discussion for many years. Although a number of developments have occurred in the last decade (e.g., the open access (OA) movement and the website Sci-Hub), everyone agrees that these difficulties still persist very widely, mainly due to the fact that paywalls still limit access to approximately 75% of scholarly documents. In this study, we compare the accessibility of recent full text articles in the field of ophthalmology in 27 established institutions located worldwide. Methods A total of 200 references from articles were retrieved using the PubMed database. Each article was individually checked for OA. Full texts of non-OA (i.e., “paywalled articles”) were examined to determine whether they were available using institutional and Hinari access in each institution studied, using “alternative ways” (i.e., PubMed Central, ResearchGate, Google Scholar, and Online Reprint Request), and using the website Sci-Hub. Results The number of full texts of “paywalled articles” available using institutional and Hinari access showed strong heterogeneity, scattered between 0% full texts to 94.8% (mean = 46.8%; SD = 31.5; median = 51.3%). We found that complementary use of “alternative ways” and Sci-Hub leads to 95.5% of full text “paywalled articles,” and also divides by 14 the average extra costs needed to obtain all full texts on publishers’ websites using pay-per-view. Conclusions The scant number of available full text “paywalled articles” in most institutions studied encourages researchers in the field of ophthalmology to use Sci-Hub to search for scientific information. The scientific community and decision-makers must unite and strengthen their efforts to find solutions to improve access to scientific literature worldwide and avoid an implosion of the scientific publishing model. This study is not an endorsement for using Sci-Hub. The authors, their institutions, and publishers accept no responsibility on behalf of readers.
Discussion on clinical examination techniques Simplified presentation of surgical procedures Brie... more Discussion on clinical examination techniques Simplified presentation of surgical procedures Brief description of surgical instruments along with their pictures wherever appropriate Glossary of key terms at the end of the chapters Numerous clinical photographs and line diagrams to support the text Undergraduate Ophthalmology is specially designed for medical students pursuing MBBS course. The book comprehensively covers the basic and clinical aspects of ophthalmology in a structured, concise, and simple manner, amply aided by illustrations for easy understanding. It includes relevant recent advances in ophthalmology. SECTION I: BASICS IN OPHTHALMOLOGY
To study the clinical profile and distribution of various subtypes of glaucoma in a referral prac... more To study the clinical profile and distribution of various subtypes of glaucoma in a referral practice in North India. A retrospective analysis was done of 2425 patients who attended the glaucoma clinic in a tertiary eye-care centre for five years from January 1995 to December 1999. A detailed history was obtained and a thorough examination was performed, including gonioscopy, disc assessment, applanation tonometry and automated perimetry. Diurnal variation of IOP and provocative tests for glaucoma were done where applicable. Primary angle closure glaucoma (PACG) was the most common glaucoma subtype. The primary open angle glaucoma (POAG) to the PACG ratio was 37:63. Chronic angle closure glaucoma (CACG) was the most common PACG subtype. The majority of CACG cases were relatively asymptomatic. Male dominance was seen for POAG, juvenile open angle glaucoma (JOAG), CACG, normal tension glaucoma (NTG) and secondary glaucomas. Female dominance was seen for ocular hypertension (OHT), acut...
DJO is distributed free to all members of DOS. A subscription to DJO comprises of 4 issues, inclu... more DJO is distributed free to all members of DOS. A subscription to DJO comprises of 4 issues, inclusive of postage charges.
Orbital mycosis is a condition characterized by opportunistic infections, fungal in origin, that ... more Orbital mycosis is a condition characterized by opportunistic infections, fungal in origin, that has the capacity to be potentially life threatening. Some of these fungi establish them-shelves in the body when the patient is immuno-compromised, uncontrolled diabetes being a very important cause and then spread rapidly throughout the body at a very fast pace. Some of the other fungi inhabit a body, which may not be necessarily compromised, remain indolent for a very long time and may cause nonspecific symptoms, and then may rapidly spread whenever the body’s immunity is compromised to a certain degree. It is very important for an ophthalmologist to have a high clinical suspicion of these conditions, so that effective treatment can be started early. This triage can at times be life saving. The typical clinical features that characterizes these conditions are that of a painful, unilateral orbital apex syndrome causing total ophthalmoplegia, corneal anesthesia and multiple cranial nerve...
With increasing emphasis on genetics as a direct cause, susceptibility modulator, or an associati... more With increasing emphasis on genetics as a direct cause, susceptibility modulator, or an association of most diseases affecting mankind, there has been generation of great interest in finding out the genetic determinants of the same. Asia represents a continent, a geographical distribution of landmass, populated by many different ethnic populations, namely, Caucasians, East Asians, South Asians, and so forth. As essentially Asia, Africa, and Europe represent the “old world,” ancient transmigrations of populations and interethnic marriages have led to a significant genetic overlap modified by epigenetic factors. Subsequently, it was this relatively “mixed” population that transmigrated to the supposed “new world” or landmasses that had isolated, pure, and indigenous populations, and the story was repeated again. Thus, currently one may expect a certain global homogeneity of genetic determinants for most diseases affecting mankind, which are, however, still modulated locally by significant environmental, social, and other epigenetic factors. This is especially so because inheritance patterns show familial repeatability, thus suggesting the presence of some form of genetic transmission, but do not always fit Mendelian patterns. They have thus been aptly included under the umbrella of being “complex” genetic disorders. With increasing cost-effective availability of better tools for genetic analysis, the disease and the search for its genetic origin have both now entered a new era of scientific query. This chapter specifically addresses the current status of genetics of eye disorders in children including strabismus, in the continent of Asia, comprising many parts, i.e., Central Asia, South Asia, Southeast Asia, East Asia, and more and a comparison with the current status in the Western world.
Journal of Pediatric Ophthalmology & Strabismus, 2002
Neurofibromatosis consists of at least two dis-tinct autosomal dominant disorders with differing ... more Neurofibromatosis consists of at least two dis-tinct autosomal dominant disorders with differing clinical manifestations.1 Neurofibromatosis type I (NF-I), originally described by von Recklinghausen and previously known as peripheral neurofibro-matosis, presents in childhood and is ...
PURPOSE To report a retrospective analysis of a combined procedure of extracapsular cataract extr... more PURPOSE To report a retrospective analysis of a combined procedure of extracapsular cataract extraction (ECCE) with heparin surface modified (HSM) posterior chamber intraocular lens (PCIOL) implantation along with primary Ahmed glaucoma valve (AGV) implantation in an attempt to optimize visual acuity gains and intraocular pressure (IOP) control in patients with phacomorphic glaucoma. METHODS ECCE with HSM PC IOL and AGV implantation was performed through two separate incisions in 15 patients diagnosed with phacomorphic glaucoma. Postoperative improvement in visual acuity and IOP control were monitored. RESULTS A steady control of IOP was maintained in all patients with minimum anti-glaucoma medications. The average visual acuity was approximately 6/24 at 3 months. CONCLUSION Superior preoperative IOP control and a shorter phacomorphic attack resulted in better postoperative vision. The successful maintenance of IOP within the desired range in this study suggests that the procedure s...
BACKGROUND & OBJECTIVE Amblyopia is one of the most common causes of visual impairment in adults ... more BACKGROUND & OBJECTIVE Amblyopia is one of the most common causes of visual impairment in adults and children, and visual loss may be permanent if not treated in time. Though many studies have been done on occlusion therapy which is the mainstay in the treatment of unilateral amblyopia, discrepancies exist in literature about quantification of treatment and follow up measures. The present study was undertaken to evaluate the factors responsible for the successful outcome of treatment and the optimum time required for the same in children with unilateral amblyopia. METHODS Baseline characteristics of 63 verbal patients with unilateral amblyopia (strabismic, anisometropic, mixed) referred to the Strabismus and Amblyopia Clinic at the Dr Rajendra Prasad Centre for Ophthalmic Sciences, New Delhi between September 2001 to December 2002 who improved to the desired level of visual acuity after treatment for amblyopia in the mentioned time period, were analyzed to assess for factors that di...
The concept of “congenital fibrosis of the extra ocular muscles” (CFEOM) was proposed in view of ... more The concept of “congenital fibrosis of the extra ocular muscles” (CFEOM) was proposed in view of increasingly common observation by the ophthalmologists where in it was noticed that many children born with disorders of ocular motility had fibrotic extra ocular muscles pointing to a myogenic pathology abnormal neuronal development [1-4]. However there was a shift in the opinion relating to etio-pathogenesis and a neurogenic and genetic basis was emphasized for these group of ocular motility disorders that share common features of dysinnervation to the ocular and facial musculature presently termed as the “congenital cranial dysinnervation disorders” by Gutowski et al., in 2003 [4]. These cases at times pose a diagnostic challenge because of a conserved partial or anomalous paradoxical innervation to the muscles which result in different combinations of involuntary eye movements.
Background The problem of access to medical information, particularly in low-income countries, ha... more Background The problem of access to medical information, particularly in low-income countries, has been under discussion for many years. Although a number of developments have occurred in the last decade (e.g., the open access (OA) movement and the website Sci-Hub), everyone agrees that these difficulties still persist very widely, mainly due to the fact that paywalls still limit access to approximately 75% of scholarly documents. In this study, we compare the accessibility of recent full text articles in the field of ophthalmology in 27 established institutions located worldwide. Methods A total of 200 references from articles were retrieved using the PubMed database. Each article was individually checked for OA. Full texts of non-OA (i.e., “paywalled articles”) were examined to determine whether they were available using institutional and Hinari access in each institution studied, using “alternative ways” (i.e., PubMed Central, ResearchGate, Google Scholar, and Online Reprint Requ...
Neurodevelopmental disorders (NDDs) compromise the development and attainment of full social and ... more Neurodevelopmental disorders (NDDs) compromise the development and attainment of full social and economic potential at individual, family, community, and country levels. Paucity of data on NDDs slows down policy and programmatic action in most developing countries despite perceived high burden. We assessed 3,964 children (with almost equal number of boys and girls distributed in 2-<6 and 6-9 year age categories) identified from five geographically diverse populations in India using cluster sampling technique (probability proportionate to population size). These were from the North-Central, i.e., Palwal (N = 998; all rural, 16.4% non-Hindu, 25.3% from scheduled caste/tribe [SC-ST] [these are considered underserved communities who are eligible for affirmative action]); North, i.e., Kangra (N = 997; 91.6% rural, 3.7% non-Hindu, 25.3% SC-ST); East, i.e., Dhenkanal (N = 981; 89.8% rural, 1.2% non-Hindu, 38.0% SC-ST); South, i.e., Hyderabad (N = 495; all urban, 25.7% non-Hindu, 27.3% S...
Familial clustering of common forms of primary strabismus like esotropia (ET) and exotropia (XT) ... more Familial clustering of common forms of primary strabismus like esotropia (ET) and exotropia (XT) is observed in a proportion of the strabismus cohort. The genetic components of this remain unidentified. Linkage studies have demonstrated susceptibility locus for primary strabismus at the STBMS1 locus on 7p22.1 as well as other loci on 4q28.3 and 7q31.2. Recently next generation sequencing (NGS) technology has emerged as a powerful tool in discovery genomics and a large number of novel disease-causing variants are being reported. In this study, we recruited informative families for subsequent genetic analysis for disease-causing variant identification. All consecutive families with two or more affected members with primary concomitant horizontal strabismus were prospectively recruited at the ophthalmic outpatients department (OPD) of Lady Hardinge Medical College, New Delhi, from August 2014 to February 2017. Detailed phenotypic evaluation and pedigree documentation was performed. Of ...
Background The problem of access to medical information, particularly in low-income countries, ha... more Background The problem of access to medical information, particularly in low-income countries, has been under discussion for many years. Although a number of developments have occurred in the last decade (e.g., the open access (OA) movement and the website Sci-Hub), everyone agrees that these difficulties still persist very widely, mainly due to the fact that paywalls still limit access to approximately 75% of scholarly documents. In this study, we compare the accessibility of recent full text articles in the field of ophthalmology in 27 established institutions located worldwide. Methods A total of 200 references from articles were retrieved using the PubMed database. Each article was individually checked for OA. Full texts of non-OA (i.e., “paywalled articles”) were examined to determine whether they were available using institutional and Hinari access in each institution studied, using “alternative ways” (i.e., PubMed Central, ResearchGate, Google Scholar, and Online Reprint Request), and using the website Sci-Hub. Results The number of full texts of “paywalled articles” available using institutional and Hinari access showed strong heterogeneity, scattered between 0% full texts to 94.8% (mean = 46.8%; SD = 31.5; median = 51.3%). We found that complementary use of “alternative ways” and Sci-Hub leads to 95.5% of full text “paywalled articles,” and also divides by 14 the average extra costs needed to obtain all full texts on publishers’ websites using pay-per-view. Conclusions The scant number of available full text “paywalled articles” in most institutions studied encourages researchers in the field of ophthalmology to use Sci-Hub to search for scientific information. The scientific community and decision-makers must unite and strengthen their efforts to find solutions to improve access to scientific literature worldwide and avoid an implosion of the scientific publishing model. This study is not an endorsement for using Sci-Hub. The authors, their institutions, and publishers accept no responsibility on behalf of readers.
Discussion on clinical examination techniques Simplified presentation of surgical procedures Brie... more Discussion on clinical examination techniques Simplified presentation of surgical procedures Brief description of surgical instruments along with their pictures wherever appropriate Glossary of key terms at the end of the chapters Numerous clinical photographs and line diagrams to support the text Undergraduate Ophthalmology is specially designed for medical students pursuing MBBS course. The book comprehensively covers the basic and clinical aspects of ophthalmology in a structured, concise, and simple manner, amply aided by illustrations for easy understanding. It includes relevant recent advances in ophthalmology. SECTION I: BASICS IN OPHTHALMOLOGY
To study the clinical profile and distribution of various subtypes of glaucoma in a referral prac... more To study the clinical profile and distribution of various subtypes of glaucoma in a referral practice in North India. A retrospective analysis was done of 2425 patients who attended the glaucoma clinic in a tertiary eye-care centre for five years from January 1995 to December 1999. A detailed history was obtained and a thorough examination was performed, including gonioscopy, disc assessment, applanation tonometry and automated perimetry. Diurnal variation of IOP and provocative tests for glaucoma were done where applicable. Primary angle closure glaucoma (PACG) was the most common glaucoma subtype. The primary open angle glaucoma (POAG) to the PACG ratio was 37:63. Chronic angle closure glaucoma (CACG) was the most common PACG subtype. The majority of CACG cases were relatively asymptomatic. Male dominance was seen for POAG, juvenile open angle glaucoma (JOAG), CACG, normal tension glaucoma (NTG) and secondary glaucomas. Female dominance was seen for ocular hypertension (OHT), acut...
DJO is distributed free to all members of DOS. A subscription to DJO comprises of 4 issues, inclu... more DJO is distributed free to all members of DOS. A subscription to DJO comprises of 4 issues, inclusive of postage charges.
Orbital mycosis is a condition characterized by opportunistic infections, fungal in origin, that ... more Orbital mycosis is a condition characterized by opportunistic infections, fungal in origin, that has the capacity to be potentially life threatening. Some of these fungi establish them-shelves in the body when the patient is immuno-compromised, uncontrolled diabetes being a very important cause and then spread rapidly throughout the body at a very fast pace. Some of the other fungi inhabit a body, which may not be necessarily compromised, remain indolent for a very long time and may cause nonspecific symptoms, and then may rapidly spread whenever the body’s immunity is compromised to a certain degree. It is very important for an ophthalmologist to have a high clinical suspicion of these conditions, so that effective treatment can be started early. This triage can at times be life saving. The typical clinical features that characterizes these conditions are that of a painful, unilateral orbital apex syndrome causing total ophthalmoplegia, corneal anesthesia and multiple cranial nerve...
With increasing emphasis on genetics as a direct cause, susceptibility modulator, or an associati... more With increasing emphasis on genetics as a direct cause, susceptibility modulator, or an association of most diseases affecting mankind, there has been generation of great interest in finding out the genetic determinants of the same. Asia represents a continent, a geographical distribution of landmass, populated by many different ethnic populations, namely, Caucasians, East Asians, South Asians, and so forth. As essentially Asia, Africa, and Europe represent the “old world,” ancient transmigrations of populations and interethnic marriages have led to a significant genetic overlap modified by epigenetic factors. Subsequently, it was this relatively “mixed” population that transmigrated to the supposed “new world” or landmasses that had isolated, pure, and indigenous populations, and the story was repeated again. Thus, currently one may expect a certain global homogeneity of genetic determinants for most diseases affecting mankind, which are, however, still modulated locally by significant environmental, social, and other epigenetic factors. This is especially so because inheritance patterns show familial repeatability, thus suggesting the presence of some form of genetic transmission, but do not always fit Mendelian patterns. They have thus been aptly included under the umbrella of being “complex” genetic disorders. With increasing cost-effective availability of better tools for genetic analysis, the disease and the search for its genetic origin have both now entered a new era of scientific query. This chapter specifically addresses the current status of genetics of eye disorders in children including strabismus, in the continent of Asia, comprising many parts, i.e., Central Asia, South Asia, Southeast Asia, East Asia, and more and a comparison with the current status in the Western world.
Journal of Pediatric Ophthalmology & Strabismus, 2002
Neurofibromatosis consists of at least two dis-tinct autosomal dominant disorders with differing ... more Neurofibromatosis consists of at least two dis-tinct autosomal dominant disorders with differing clinical manifestations.1 Neurofibromatosis type I (NF-I), originally described by von Recklinghausen and previously known as peripheral neurofibro-matosis, presents in childhood and is ...
PURPOSE To report a retrospective analysis of a combined procedure of extracapsular cataract extr... more PURPOSE To report a retrospective analysis of a combined procedure of extracapsular cataract extraction (ECCE) with heparin surface modified (HSM) posterior chamber intraocular lens (PCIOL) implantation along with primary Ahmed glaucoma valve (AGV) implantation in an attempt to optimize visual acuity gains and intraocular pressure (IOP) control in patients with phacomorphic glaucoma. METHODS ECCE with HSM PC IOL and AGV implantation was performed through two separate incisions in 15 patients diagnosed with phacomorphic glaucoma. Postoperative improvement in visual acuity and IOP control were monitored. RESULTS A steady control of IOP was maintained in all patients with minimum anti-glaucoma medications. The average visual acuity was approximately 6/24 at 3 months. CONCLUSION Superior preoperative IOP control and a shorter phacomorphic attack resulted in better postoperative vision. The successful maintenance of IOP within the desired range in this study suggests that the procedure s...
BACKGROUND & OBJECTIVE Amblyopia is one of the most common causes of visual impairment in adults ... more BACKGROUND & OBJECTIVE Amblyopia is one of the most common causes of visual impairment in adults and children, and visual loss may be permanent if not treated in time. Though many studies have been done on occlusion therapy which is the mainstay in the treatment of unilateral amblyopia, discrepancies exist in literature about quantification of treatment and follow up measures. The present study was undertaken to evaluate the factors responsible for the successful outcome of treatment and the optimum time required for the same in children with unilateral amblyopia. METHODS Baseline characteristics of 63 verbal patients with unilateral amblyopia (strabismic, anisometropic, mixed) referred to the Strabismus and Amblyopia Clinic at the Dr Rajendra Prasad Centre for Ophthalmic Sciences, New Delhi between September 2001 to December 2002 who improved to the desired level of visual acuity after treatment for amblyopia in the mentioned time period, were analyzed to assess for factors that di...
The concept of “congenital fibrosis of the extra ocular muscles” (CFEOM) was proposed in view of ... more The concept of “congenital fibrosis of the extra ocular muscles” (CFEOM) was proposed in view of increasingly common observation by the ophthalmologists where in it was noticed that many children born with disorders of ocular motility had fibrotic extra ocular muscles pointing to a myogenic pathology abnormal neuronal development [1-4]. However there was a shift in the opinion relating to etio-pathogenesis and a neurogenic and genetic basis was emphasized for these group of ocular motility disorders that share common features of dysinnervation to the ocular and facial musculature presently termed as the “congenital cranial dysinnervation disorders” by Gutowski et al., in 2003 [4]. These cases at times pose a diagnostic challenge because of a conserved partial or anomalous paradoxical innervation to the muscles which result in different combinations of involuntary eye movements.
Background The problem of access to medical information, particularly in low-income countries, ha... more Background The problem of access to medical information, particularly in low-income countries, has been under discussion for many years. Although a number of developments have occurred in the last decade (e.g., the open access (OA) movement and the website Sci-Hub), everyone agrees that these difficulties still persist very widely, mainly due to the fact that paywalls still limit access to approximately 75% of scholarly documents. In this study, we compare the accessibility of recent full text articles in the field of ophthalmology in 27 established institutions located worldwide. Methods A total of 200 references from articles were retrieved using the PubMed database. Each article was individually checked for OA. Full texts of non-OA (i.e., “paywalled articles”) were examined to determine whether they were available using institutional and Hinari access in each institution studied, using “alternative ways” (i.e., PubMed Central, ResearchGate, Google Scholar, and Online Reprint Requ...
Neurodevelopmental disorders (NDDs) compromise the development and attainment of full social and ... more Neurodevelopmental disorders (NDDs) compromise the development and attainment of full social and economic potential at individual, family, community, and country levels. Paucity of data on NDDs slows down policy and programmatic action in most developing countries despite perceived high burden. We assessed 3,964 children (with almost equal number of boys and girls distributed in 2-<6 and 6-9 year age categories) identified from five geographically diverse populations in India using cluster sampling technique (probability proportionate to population size). These were from the North-Central, i.e., Palwal (N = 998; all rural, 16.4% non-Hindu, 25.3% from scheduled caste/tribe [SC-ST] [these are considered underserved communities who are eligible for affirmative action]); North, i.e., Kangra (N = 997; 91.6% rural, 3.7% non-Hindu, 25.3% SC-ST); East, i.e., Dhenkanal (N = 981; 89.8% rural, 1.2% non-Hindu, 38.0% SC-ST); South, i.e., Hyderabad (N = 495; all urban, 25.7% non-Hindu, 27.3% S...
Familial clustering of common forms of primary strabismus like esotropia (ET) and exotropia (XT) ... more Familial clustering of common forms of primary strabismus like esotropia (ET) and exotropia (XT) is observed in a proportion of the strabismus cohort. The genetic components of this remain unidentified. Linkage studies have demonstrated susceptibility locus for primary strabismus at the STBMS1 locus on 7p22.1 as well as other loci on 4q28.3 and 7q31.2. Recently next generation sequencing (NGS) technology has emerged as a powerful tool in discovery genomics and a large number of novel disease-causing variants are being reported. In this study, we recruited informative families for subsequent genetic analysis for disease-causing variant identification. All consecutive families with two or more affected members with primary concomitant horizontal strabismus were prospectively recruited at the ophthalmic outpatients department (OPD) of Lady Hardinge Medical College, New Delhi, from August 2014 to February 2017. Detailed phenotypic evaluation and pedigree documentation was performed. Of ...
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