Articles

101–110 of 232 articles Page 11 of 24
All Cornea 36 Cataract 17 Glaucoma 13 Retina & Vitreous 72 Neurophthalmology 8 Oculoplasty 15 Uvea & Inflammatory Diseases 24 Miscellaneous 20 Oncology 9 Pediatric Ophthalmology 15
  1. 2 Apr 2021 10 min read

    Diplopia and Hess Charting

    Diplopia Charting Diplopia chart is the record of separation of the diplopic or double images in the nine positions of gaze. It can be plotted charted in patients who cooperate and can appreciate the double vision and with incomitant or comitant deviation. The method The patient should be comfortable with his head erect and should preferably be still throughout the examination. The test is preferably carried out in a dark room. Red glass is put in front of one of the eyes (red in front of right, R for R, is a convention). It is desirable to use Armstrong goggles since these are shaped to fit the orbital margin and therefore patient would be looking only through the colored medium. The examiner holds the torch (vertical source of light) at around ½ m or 1 m (It is important to mention the distance on the chart). This source of light could be horizontal if the complaint is of vertical separation of images The light is held directly in front of the patient at first. If the patient sees a

    Dr. Jitendra Jethani, MS, DO, DNB, FNB
  2. 2 Apr 2021 49 min read

    Viral Uveitis

    Viral uveitis has myriad presentations. They may present as anterior uveitis, intermediate uveitis, acute retinal necrosis (ARN), progressive outer retinal necrosis (PORN) and neuroretinitis. The causative viruses mainly include herpes group of viruses and human immunodeficiency virus (HIV). Other DNA viruses which cause uveitis are poxviruses, adenoviruses especially those that produce epidemic keratoconjunctivitis and pharyngoconjunctival fever. RNA viruses isolated are influenza virus, mumps virus, measles virus, rubella virus, rift valley fever virus and Newcastle virus. Here we have discussed all the different types of viral uveitis except opportunistic viral infections in HIV. ANTERIOR UVEITIS Viral anterior uveitis is caused mainly by herpes simplex virus (HSV) type 1 and 2, varicella zoster virus (VZV), cytomegalovirus virus (CMV), Epstein-Barr virus (EBV) and human herpes virus (HHV) type 6, 7 and 8 (1-3). Herpes literally means ‘to crawl’ from the Greek word ‘herpein’. Herpes

    Dr. Vinita Rao · Dr. Gunjan Deshpande
  3. 2 Apr 2021 9 min read

    A Beginners Guide to Ophthalmic Surgical Microscope

    An operating surgical microscope is the most important optical instrument in the modern era of ophthalmic surgeries. It provides the surgeon with a magnified and illuminated high-quality image of the small ophthalmic structures. Being binocular the surgical microscopes gives the additional benefit of high-quality stereoscopy. History The first German doctor to use a stereomicroscope was Dr. Hans Hinselmann (1884-1959), Prof. of Gynaecology under Dr. Otto von Franque at the University Clinic, Bonn, who adapted in 1925 a Leitz stereomicroscope with coaxial illumination to a movable floor stand. He named IT “colposcope” and used it to visualize the female genital organs particularly for cancer of the cervix. Dr. Hans Littmann (1908 – 1991), head of Med-Lab at Zeiss OptonOberkochen, West Germany (now Carl Zeiss A.G.) and his team of technicians designed in 1953 their first ophthalmic operating microscope Prerequisites for an ideal operating microscope Must have stereoscopic visualization.

    Dr. Rohit Rao · Dr. Tamonash Basu
  4. 2 Apr 2021 38 min read

    Idiopathic Macular Hole

    Introduction Recent advances in the pathogenesis, classification, and surgical intervention of idiopathic macular holes have generated a renewed interest in this entity. Better indicators of the visual outcome, as well as refinements in the surgical technique, have led to improvements in the success of macular hole surgery. Clinical characterization and theories on the pathogenesis of macular hole have continued to evolve. Although originally thought to be the result of trauma, it is now recognized that most macular holes occur in the absence of antecedent injury and are referred to as idiopathic. Theories for the pathogenesis of idiopathic macular holes have included progressive thinning of the foveal tissue and pre hole cyst formation. The primary pathogenic role of the vitreous was suggested by studies that indicated a low relative risk for macular hole formation in eyes with complete posterior vitreous detachment. Gass proposed a theory whereby shrinkage of adherent cortical vitreo

    Sandeep Saxena, M.S., MAMS
  5. 2 Apr 2021 14 min read

    Eales Disease: Current Concepts in Etiopathogenesis and Management

    Introduction Eales’ disease is an idiopathic retinal periphlebitis that primarily affects the peripheral retina in young adults. Eales’ disease was first described by Henry Eales, a British ophthalmologist, in 1880 and 1882.1,2 He found it in seven young, male patients ranging in age from 14 to 29 years with recurrent vitreous hemorrhage. In addition, these patients had history of headache, variation in peripheral circulation, chronic constipation and epistaxis. In the next century, the disease was redefined by several investigators. 3-6 Elliot first recognized the inflammation of retinal vein and described it as periphlebitis retinae.4 Subsequently several investigators documented both venular and arteriolar inflammation.5,7 Eales’ disease most commonly affects healthy young adult males and is an important cause of preventable blindness in young adults. The predominant age of onset of symptoms is 20-30 years. The disease is more commonly seen in the Indian subcontinent. However, it ha

    Sandeep Saxena, M.S., MAMS
  6. 2 Apr 2021 6 min read

    Malarial Retinopathy: A Diagnostic Clue

    Introduction Malaria is the most important of parasitic diseases of humans and remains today, as it has been for centuries a large burden on tropical communities. Cerebral malaria is the most important complication of falciparum malaria and also the leading cause of death in malaria 1. It is defined as an acute, symmetric encephalopathy associated with sequestration of parasite-infected erythrocytes in the cerebral vessels and capillaries in patients with falciparum malaria 2. WHO Criteria for Diagnosis The World Health Organization has laid down definite guidelines for diagnosis and management of cerebral malaria 3. This definition requires the presence of unarousable coma using the Glasgow Coma Scale (GCS), exclusion of other encephalitides, especially bacterial meningitis and if possible, locally prevalent encephalitis and the presence of asexual forms of P. falciparum in the blood film. Retinal Involvement in Cerebral Malaria Eye being an extension of the brain, retina provides a u

    Sandeep Saxena, M.S., MAMS · Shaili Misra, MBBS · +1 other
  7. 2 Apr 2021 60 min read

    Retinal vein occlusion

    Introduction Retinal vein occlusion (RVO) is the second most common retinal vascular disease to cause visual loss in adults after diabetic retinopathy. RVO has been classified into two main types, namely Central retinal vein occlusion (CRVO), Branch retinal vein occlusion (BRVO), the latter being more prevalent. Hemi-retinal vein occlusion has been classified separately since pathogenetically they are different as compared to the above two groups. In the following chapter a brief introduction to these variants of RVO, along with their epidemiology, clinicopathological profile, and treatment has been discussed. Epidemiology [1] The most recently published study summarizing 68,751 individuals from 15 studies, quoted that the prevalence of RVO was 5.20 per 1000 (for any form of RVO). The prevalence of BRVO alone was 4.42 per 1000 (95% CI 3.65–5.19) and that of CRVO was 0.80 per 1000. According to Hayreh et al, prevalence varied by ethnicity and increased with age, but do not differ by gen

    Dr. P. Mahesh Shanmugam, MBBS, DO, FRCSEd, PhD, FAICO · Divyansh Mishra · +1 other
  8. 2 Apr 2021 13 min read

    Perfluorocarbons in Ophthalmology

    INTRODUCTION Perfluorocarbon liquids (PFCLs) were first developed in 1970s as possible substitutes to erythrocytes[1],[2] because of their capacity to dissolve relatively large amounts of oxygen. Initial trials with these compounds focused on their feasibility to be used as blood substitutes. These experiments proved the biocompatibility of these compounds. Based on their properties, they were then introduced for intraocular use, in what has become a milestone in vitreoretinal surgery. After animal studies confirmed the safety of PFCL compounds as vitreous substitutes, Chang et al in 1987 first described the successful intraocular use of low viscosity liquid fluorocarbons (perfluorotributylamine and perfluorodecalin) in four patients with complicated retinal detachments.[3],[4] Long-term tamponade in animal models demonstrated retinal atrophy and retinal necrosis at the perfluorocarbon aqueous interface after 4 weeks even when highly purified PFCL compounds (perfluorodecalin) were used

    Dr. Abhishek R. Kothari
  9. 2 Apr 2021 31 min read

    Optical Coherence Tomography- Evolution and Clinical Applications

    1. Introduction Optical coherence tomography (OCT) is a noninvasive imaging modality that has revolutionized the practice of clinical ophthalmology over the past decade. OCT provides high-resolution cross-sectional images of the retina, optic nerve head and retinal nerve fibre layer (RNFL) unobtainable by any other current modality, and enables qualitative and quantitative evaluation. As opposed to other retinal imaging modalities that provide én face images, it provides for sectional information, and in that sense is analogous to an in vivo “optical biopsy” (Figure 1). It is safe, fast, reproducible, does not require greatly skilled technicians, and has minimal, if any, interobserver issues. Several advances in recent times have contributed to vast improvements in resolution and speed of OCT devices, and expanded their applications manifold. In 2010, in the US alone, an estimated 16 million OCT procedures were done, amounting to $ 780 million in reimbursement.[1] Fig 1. Macular OCT wi

    Dr. Abhishek R. Kothari
  10. 2 Apr 2021 8 min read

    Macular Buckle Indications, Technique and Challenges

    Macular Buckling (MB) is simply defined as a modified scleral buckle (SB) surgery where the sclera is remodeled to appose the retina to the sclero-choroidal complex thereby relieving the traction. Unlike conventional SB, where buckle element is placed circumferentially around the eyeball, MB element is placed behind the globe under macula indenting the sclera from posterior. MB has been tried by various surgeons for varied purpose. In general, situations, where MB has been attempted for a variety of posterior pole diseases, are as follows- Eyes with pathological myopia (PM) associated with posterior staphyloma (PS) Eyes with Optic Pit abnormalities Eyes requiring scleral remodeling posterior to the equator, where routine SB may not be effective In all practical situations, pathological myopia having posterior staphyloma associated macular changes is presently the most common indications for MB surgery. The other 2 situations have been very rarely attempted with MB surgery, with limited

    Dr. Pradeep Susvar · Dr. Kushal Delhiwala