The British journal of ophthalmology, Jan 12, 2016
Surgical management of complete third nerve paralysis is a challenge. While several techniques ha... more Surgical management of complete third nerve paralysis is a challenge. While several techniques have been described over the years, they result in less than satisfactory outcomes with residual deviations in primary gaze or postoperative drifts. One of the described techniques for management of oculomotor palsy has been medial transposition of the lateral rectus muscle which provides a good surgical alternative but often can result in undercorrection. We describe a modification of the existing technique of medial transposition of the split lateral rectus by force augmentation through the use of equatorial fixation sutures resulting in an improved outcome in primary gaze alignment. The modified technique involves splitting of the lateral rectus into two halves followed by transposing the superior half from below the superior oblique and superior rectus and inferior half from below the inferior oblique and inferior rectus to attach them at the superior and inferior edge of the medial re...
The number of erythrocytes fell when co-cultured with cell preparations derived from mouse spleen... more The number of erythrocytes fell when co-cultured with cell preparations derived from mouse spleen, thymus, bone marrow, or peritoneal exudate (PE) cells. Erythrocyte-depletion activities (EDA) of different leukocyte preparations were in the order PE > spleen > thymus > bone marrow. Adherent, nonadherent, T-depleted, and T-enriched cell subpopulations had comparable EDA. Spleen cells from athymic nude mice, however, lacked significant EDA. In addition, EDA was boosted by Concanavalin A (Con A) but not by lipopolysaccharide, indicating that T cells may play a crucial role in inducing EDA in spleen cells. Paraformaldehyde-fixed spleen or PE cells, as well as membrane preparations isolated from spleen cells, efficiently lysed erythrocytes. Erythrocyte ghost membranes inhibited erythrocyte lysis by control or paraformaldehyde-fixed spleen cells. Treatment with hamster anti-mouse Fas or anti-mouse tumor necrosis factor receptor (TNFR) antibody could opsonize erythrocytes for faster depletion by spleen cells, suggesting an expression of Fas and TNFR on erythrocytes. TNF alpha could lyse erythrocytes in a dose-dependent fashion. Additionally, enhanced spleen cell EDA induced in response to succenyl Con-A could be blocked by anti-TNF alpha antibodies. Our results provide evidence for a direct cell-mediated cytotoxicity (CMC) of erythrocytes by leukocytes. A role of molecules of Fas and the TNF family in CMC of erythrocytes has also been suggested. Further work is needed to understand if, and to what extent, CMC of erythrocytes contributes to erythrocyte destruction in vivo and to determine its patho-physiological significance.
The aim of the study is to identify the causes, demographic and clinical profile and evaluate fin... more The aim of the study is to identify the causes, demographic and clinical profile and evaluate final visual outcome of pediatric ocular injuries. Two hundred and four children aged fourteen years or less presenting to the emergency services of a tertiary care centre with ocular injury were included. Demographic data, nature and cause of injury, duration between injury and presentation to an ophthalmologist and the diagnosis were recorded. Evaluation of visual acuity, anterior segment and fundus were done. All patients were appropriately managed and followed up on days 1, 7, 1 month, 3 and 6 months. Majority of injuries occurred in children of 5 years and older (87.7%). There were 133 (65.1%) boys and 71 (34.9%) girls. Forty-nine (24%) cases presented within 6 hours of injury while 70 (34.3%) presented after more than 24 hours after trauma. Most common cause of injury was bow and arrow (15.2%) followed by household appliances(14.3%). Closed globe injuries accounted for 42.2% injuries, open globe for 53.9% and 3.9% were chemical injuries. Best corrected visual acuity of 6/12 or better was achieved in 79 eyes (91.86%) in closed globe group. However, only 17 eyes (15.45%) in open globe group could achieve this. Most ocular injuries in children are preventable and occur from unsupervised games like bow and arrow and firecracker, which can lead to significant visual loss.
Glaucoma, the second leading cause of blindness, is characterized by changes in the optic disc an... more Glaucoma, the second leading cause of blindness, is characterized by changes in the optic disc and visual field defects. The elevated intraocular pressure was considered the prime factor responsible for the glaucomatous optic neuropathy involving death of retinal ganglion cells and their axons. Extensive investigations into the pathophysiology of glaucoma now reveal the role of multiple factors in the development of retinal ganglion cell death. A better understanding of the pathophysiological mechanisms involved in the onset and progression of glaucomatous optic neuropathy is crucial in the development of better therapeutic options. This review is an effort to summarize the current concepts in the pathophysiology of glaucoma so that newer therapeutic targets can be recognized. The literature available in the National Medical Library and online Pubmed search engine was used for literature review.
To compare the efficacy of intravenous methylprednisolone and intravenous dexamethasone on visual... more To compare the efficacy of intravenous methylprednisolone and intravenous dexamethasone on visual recovery and evaluate their side-effects for the treatment of optic neuritis. Prospective, randomized case-controlled study including 21 patients of acute optic neuritis presenting within eight days of onset and with visual acuity less then 20/60 in the affected eye who were randomly divided into two groups. Group I received intravenous dexamethasone 200 mg once daily for three days and Group II received intravenous methylprednisolone 250 mg/six-hourly for three days followed by oral prednisolone for 11 days. Parameters tested were pupillary reactions, visual acuity, fundus findings, color vision, contrast sensitivity, Goldmann visual fields and biochemical investigations for all patients at presentation and follow-up. Both groups were age and sex-matched. LOGMAR visual acuity at presentation was 1.10 +/- 0.52 in Group I and 1.52 +/- 0.43 in Group II. On day 90 of steroid therapy, visual acuity improved to 0.28 +/- 0.33 in Group I and 0.36 +/- 0.41 in Group II ( P =0.59). At three months there was no statistically significant difference in the color vision, contrast sensitivity, stereoacuity, Goldman fields and the amplitude and latency of visually evoked response between the two groups. The concentration of vitamin C, glucose, sodium, potassium, urea and creatinine were within the reported normal limits. Intravenous dexamethasone is an effective treatment for optic neuritis. However, larger studies are required to establish it as a safe, inexpensive and effective modality for the treatment of optic neuritis.
Evaluation of brain cluster activation using the functional magnetic resonance imaging (fMRI) and... more Evaluation of brain cluster activation using the functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) was sought in strabismic amblyopes. In this hospital-based case-control cross-sectional study, fMRI and DTI were conducted in strabismic amblyopes before initiation of any therapy and after visual recovery following the administration of occlusion therapy. FMRI was performed in 10 strabismic amblyopic subjects (baseline group) and in 5 left strabismic amblyopic children post-occlusion therapy after two-line visual improvement. Ten age-matched healthy children with right ocular dominance formed control group. Structural and functional MRI was carried out on 1.5T MR scanner. The visual task consisted of 8 Hz flickering checkerboard with red dot and occasional green dot. Blood-oxygen-level-dependent (BOLD) fMRI was analyzed using statistical parametric mapping and DTI on NordicIce (NordicNeuroLab) softwares. Reduced occipital activation was elicited when view...
DOAJ is hosted by Lund University, Sweden DOAJ acknowledges support from INASP DOAJ acknowledges ... more DOAJ is hosted by Lund University, Sweden DOAJ acknowledges support from INASP DOAJ acknowledges support from the National Library of Sweden DOAJ acknowledges support from Swedish Library Association Sponsor of Long Term Archiving DOAJ ...
To compare and evaluate Teller Acuity Cards (TAC) and Cardiff Acuity Cards (CAC) to assess vision... more To compare and evaluate Teller Acuity Cards (TAC) and Cardiff Acuity Cards (CAC) to assess vision in children below the age of two. The study evaluated TAC and CAC to assess visual acuity in 90 normal children divided into three age groups, 0-6 months (group I), 6-12 months (group II) and 12-24 months (group III). 30 cases of unilateral amblyopiogenic conditions, 10 cases each of unilateral refractive error, unilateral esotropia, and unilateral cataract, were also examined. Trained optometrists carried out binocular testing followed by monocular testing, and recorded the test time in each case. The mean visual acuity (in Snellen units) and standard deviation (in octaves) in the three age groups of normal children, I, II, III respectively were 6/44 +/- 0.54, 6/21 +/- 0.37 and 6/21 +/- 0.41 (binocularly by TAC) and 6/46 +/- 0.80, 6/21 +/- 0.59 and 6/14.5 +/- 0.84 (binocularly by CAC). Although the time taken for testing with CAC was less, its coefficient of variance was greater for all age groups as compared to TAC. Diminution of visual acuity could be assessed correctly by both the tests in cases of strabismus and cataract, but not in some cases of refractive error. CAC is a useful and child-friendly test. It can be used clinically but may miss some cases of visually significant refractive errors. TAC is a more dependable test to assess amblyopiogenic conditions despite the use of gratings.
A 38-year-old immunocompetent man presented with a horizontal supranuclear gaze palsy as the only... more A 38-year-old immunocompetent man presented with a horizontal supranuclear gaze palsy as the only neurologic manifestation of a pontine tuberculoma. Although a biopsy of the brain lesion was not performed, it was attributed to tuberculosis because of chest x-ray evidence. The patient was given empirical anti-tuberculous therapy. After one month, the gaze palsy had fully recovered and repeat MRI showed a decrease in the size of the lesion. This is the first reported case of supranuclear gaze palsy without diplopia as a manifestation of a tuberculous brain stem lesion.
A method is presented for computing the equilibrium structures of rotationally distorted stars an... more A method is presented for computing the equilibrium structures of rotationally distorted stars and the rotationally and tidally distorted primary components of stars in binary systems. The method is based on the averaging technique of Kippenhahn and Thomas (1970) and utilizes the concepts of Roche equipotentials (Kopal, 1972). The method takes into account terms up to second-order of smallness in the rotational and tidal distortion parameters. The use of the method in obtaining the equilibrium structures of certain rotationally and/or tidally distorted models of main-sequence stars is illustrated.
Fluid overload is a risk factor for poor outcome in intensive care; thus volume loading should be... more Fluid overload is a risk factor for poor outcome in intensive care; thus volume loading should be tailored towards patients who are likely to increase stroke volume. We aimed to evaluate the paediatric predictive ability (stroke volume increase of at least 15 % after fluid bolus) of novel and established volumetric and dynamic haemodynamic variables, and assess the influence of baseline contractility on response. We assessed 142 volume loading episodes (10 ml/kg crystalloid) in 100 critically ill ventilated children, median (interquartile) weight 10 (5.6-15) kg. Eight advanced haemodynamic variables were assessed using two commercially available devices. Systemic ventricular contractility was measured as the maximum rate of systolic arterial pressure rise. Overall, predictive ability was poor, with volumetric variables performing better than dynamic (area under receiver operating characteristic curves ranged from 0.53 to 0.67). The best predictor was total end-diastolic volume index...
The British journal of ophthalmology, Jan 12, 2016
Surgical management of complete third nerve paralysis is a challenge. While several techniques ha... more Surgical management of complete third nerve paralysis is a challenge. While several techniques have been described over the years, they result in less than satisfactory outcomes with residual deviations in primary gaze or postoperative drifts. One of the described techniques for management of oculomotor palsy has been medial transposition of the lateral rectus muscle which provides a good surgical alternative but often can result in undercorrection. We describe a modification of the existing technique of medial transposition of the split lateral rectus by force augmentation through the use of equatorial fixation sutures resulting in an improved outcome in primary gaze alignment. The modified technique involves splitting of the lateral rectus into two halves followed by transposing the superior half from below the superior oblique and superior rectus and inferior half from below the inferior oblique and inferior rectus to attach them at the superior and inferior edge of the medial re...
The number of erythrocytes fell when co-cultured with cell preparations derived from mouse spleen... more The number of erythrocytes fell when co-cultured with cell preparations derived from mouse spleen, thymus, bone marrow, or peritoneal exudate (PE) cells. Erythrocyte-depletion activities (EDA) of different leukocyte preparations were in the order PE > spleen > thymus > bone marrow. Adherent, nonadherent, T-depleted, and T-enriched cell subpopulations had comparable EDA. Spleen cells from athymic nude mice, however, lacked significant EDA. In addition, EDA was boosted by Concanavalin A (Con A) but not by lipopolysaccharide, indicating that T cells may play a crucial role in inducing EDA in spleen cells. Paraformaldehyde-fixed spleen or PE cells, as well as membrane preparations isolated from spleen cells, efficiently lysed erythrocytes. Erythrocyte ghost membranes inhibited erythrocyte lysis by control or paraformaldehyde-fixed spleen cells. Treatment with hamster anti-mouse Fas or anti-mouse tumor necrosis factor receptor (TNFR) antibody could opsonize erythrocytes for faster depletion by spleen cells, suggesting an expression of Fas and TNFR on erythrocytes. TNF alpha could lyse erythrocytes in a dose-dependent fashion. Additionally, enhanced spleen cell EDA induced in response to succenyl Con-A could be blocked by anti-TNF alpha antibodies. Our results provide evidence for a direct cell-mediated cytotoxicity (CMC) of erythrocytes by leukocytes. A role of molecules of Fas and the TNF family in CMC of erythrocytes has also been suggested. Further work is needed to understand if, and to what extent, CMC of erythrocytes contributes to erythrocyte destruction in vivo and to determine its patho-physiological significance.
The aim of the study is to identify the causes, demographic and clinical profile and evaluate fin... more The aim of the study is to identify the causes, demographic and clinical profile and evaluate final visual outcome of pediatric ocular injuries. Two hundred and four children aged fourteen years or less presenting to the emergency services of a tertiary care centre with ocular injury were included. Demographic data, nature and cause of injury, duration between injury and presentation to an ophthalmologist and the diagnosis were recorded. Evaluation of visual acuity, anterior segment and fundus were done. All patients were appropriately managed and followed up on days 1, 7, 1 month, 3 and 6 months. Majority of injuries occurred in children of 5 years and older (87.7%). There were 133 (65.1%) boys and 71 (34.9%) girls. Forty-nine (24%) cases presented within 6 hours of injury while 70 (34.3%) presented after more than 24 hours after trauma. Most common cause of injury was bow and arrow (15.2%) followed by household appliances(14.3%). Closed globe injuries accounted for 42.2% injuries, open globe for 53.9% and 3.9% were chemical injuries. Best corrected visual acuity of 6/12 or better was achieved in 79 eyes (91.86%) in closed globe group. However, only 17 eyes (15.45%) in open globe group could achieve this. Most ocular injuries in children are preventable and occur from unsupervised games like bow and arrow and firecracker, which can lead to significant visual loss.
Glaucoma, the second leading cause of blindness, is characterized by changes in the optic disc an... more Glaucoma, the second leading cause of blindness, is characterized by changes in the optic disc and visual field defects. The elevated intraocular pressure was considered the prime factor responsible for the glaucomatous optic neuropathy involving death of retinal ganglion cells and their axons. Extensive investigations into the pathophysiology of glaucoma now reveal the role of multiple factors in the development of retinal ganglion cell death. A better understanding of the pathophysiological mechanisms involved in the onset and progression of glaucomatous optic neuropathy is crucial in the development of better therapeutic options. This review is an effort to summarize the current concepts in the pathophysiology of glaucoma so that newer therapeutic targets can be recognized. The literature available in the National Medical Library and online Pubmed search engine was used for literature review.
To compare the efficacy of intravenous methylprednisolone and intravenous dexamethasone on visual... more To compare the efficacy of intravenous methylprednisolone and intravenous dexamethasone on visual recovery and evaluate their side-effects for the treatment of optic neuritis. Prospective, randomized case-controlled study including 21 patients of acute optic neuritis presenting within eight days of onset and with visual acuity less then 20/60 in the affected eye who were randomly divided into two groups. Group I received intravenous dexamethasone 200 mg once daily for three days and Group II received intravenous methylprednisolone 250 mg/six-hourly for three days followed by oral prednisolone for 11 days. Parameters tested were pupillary reactions, visual acuity, fundus findings, color vision, contrast sensitivity, Goldmann visual fields and biochemical investigations for all patients at presentation and follow-up. Both groups were age and sex-matched. LOGMAR visual acuity at presentation was 1.10 +/- 0.52 in Group I and 1.52 +/- 0.43 in Group II. On day 90 of steroid therapy, visual acuity improved to 0.28 +/- 0.33 in Group I and 0.36 +/- 0.41 in Group II ( P =0.59). At three months there was no statistically significant difference in the color vision, contrast sensitivity, stereoacuity, Goldman fields and the amplitude and latency of visually evoked response between the two groups. The concentration of vitamin C, glucose, sodium, potassium, urea and creatinine were within the reported normal limits. Intravenous dexamethasone is an effective treatment for optic neuritis. However, larger studies are required to establish it as a safe, inexpensive and effective modality for the treatment of optic neuritis.
Evaluation of brain cluster activation using the functional magnetic resonance imaging (fMRI) and... more Evaluation of brain cluster activation using the functional magnetic resonance imaging (fMRI) and diffusion tensor imaging (DTI) was sought in strabismic amblyopes. In this hospital-based case-control cross-sectional study, fMRI and DTI were conducted in strabismic amblyopes before initiation of any therapy and after visual recovery following the administration of occlusion therapy. FMRI was performed in 10 strabismic amblyopic subjects (baseline group) and in 5 left strabismic amblyopic children post-occlusion therapy after two-line visual improvement. Ten age-matched healthy children with right ocular dominance formed control group. Structural and functional MRI was carried out on 1.5T MR scanner. The visual task consisted of 8 Hz flickering checkerboard with red dot and occasional green dot. Blood-oxygen-level-dependent (BOLD) fMRI was analyzed using statistical parametric mapping and DTI on NordicIce (NordicNeuroLab) softwares. Reduced occipital activation was elicited when view...
DOAJ is hosted by Lund University, Sweden DOAJ acknowledges support from INASP DOAJ acknowledges ... more DOAJ is hosted by Lund University, Sweden DOAJ acknowledges support from INASP DOAJ acknowledges support from the National Library of Sweden DOAJ acknowledges support from Swedish Library Association Sponsor of Long Term Archiving DOAJ ...
To compare and evaluate Teller Acuity Cards (TAC) and Cardiff Acuity Cards (CAC) to assess vision... more To compare and evaluate Teller Acuity Cards (TAC) and Cardiff Acuity Cards (CAC) to assess vision in children below the age of two. The study evaluated TAC and CAC to assess visual acuity in 90 normal children divided into three age groups, 0-6 months (group I), 6-12 months (group II) and 12-24 months (group III). 30 cases of unilateral amblyopiogenic conditions, 10 cases each of unilateral refractive error, unilateral esotropia, and unilateral cataract, were also examined. Trained optometrists carried out binocular testing followed by monocular testing, and recorded the test time in each case. The mean visual acuity (in Snellen units) and standard deviation (in octaves) in the three age groups of normal children, I, II, III respectively were 6/44 +/- 0.54, 6/21 +/- 0.37 and 6/21 +/- 0.41 (binocularly by TAC) and 6/46 +/- 0.80, 6/21 +/- 0.59 and 6/14.5 +/- 0.84 (binocularly by CAC). Although the time taken for testing with CAC was less, its coefficient of variance was greater for all age groups as compared to TAC. Diminution of visual acuity could be assessed correctly by both the tests in cases of strabismus and cataract, but not in some cases of refractive error. CAC is a useful and child-friendly test. It can be used clinically but may miss some cases of visually significant refractive errors. TAC is a more dependable test to assess amblyopiogenic conditions despite the use of gratings.
A 38-year-old immunocompetent man presented with a horizontal supranuclear gaze palsy as the only... more A 38-year-old immunocompetent man presented with a horizontal supranuclear gaze palsy as the only neurologic manifestation of a pontine tuberculoma. Although a biopsy of the brain lesion was not performed, it was attributed to tuberculosis because of chest x-ray evidence. The patient was given empirical anti-tuberculous therapy. After one month, the gaze palsy had fully recovered and repeat MRI showed a decrease in the size of the lesion. This is the first reported case of supranuclear gaze palsy without diplopia as a manifestation of a tuberculous brain stem lesion.
A method is presented for computing the equilibrium structures of rotationally distorted stars an... more A method is presented for computing the equilibrium structures of rotationally distorted stars and the rotationally and tidally distorted primary components of stars in binary systems. The method is based on the averaging technique of Kippenhahn and Thomas (1970) and utilizes the concepts of Roche equipotentials (Kopal, 1972). The method takes into account terms up to second-order of smallness in the rotational and tidal distortion parameters. The use of the method in obtaining the equilibrium structures of certain rotationally and/or tidally distorted models of main-sequence stars is illustrated.
Fluid overload is a risk factor for poor outcome in intensive care; thus volume loading should be... more Fluid overload is a risk factor for poor outcome in intensive care; thus volume loading should be tailored towards patients who are likely to increase stroke volume. We aimed to evaluate the paediatric predictive ability (stroke volume increase of at least 15 % after fluid bolus) of novel and established volumetric and dynamic haemodynamic variables, and assess the influence of baseline contractility on response. We assessed 142 volume loading episodes (10 ml/kg crystalloid) in 100 critically ill ventilated children, median (interquartile) weight 10 (5.6-15) kg. Eight advanced haemodynamic variables were assessed using two commercially available devices. Systemic ventricular contractility was measured as the maximum rate of systolic arterial pressure rise. Overall, predictive ability was poor, with volumetric variables performing better than dynamic (area under receiver operating characteristic curves ranged from 0.53 to 0.67). The best predictor was total end-diastolic volume index...
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