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#Review

86 articles
  1. Articles 1 Apr 2021 8 min read

    Intermittent Exotropia Simplified for the Postgraduates

    Intermittent exotropia (IXT) is the most common type of strabismus in children as well as adults, especially in the Asian and South Asian populations. Owing to the intermittent nature of exotropia there is usually good binocular function and stereoacuity at near fixation Small-angle exotropia is observed in normal neonates which usually disappears by the age of 2-4 months. Most adults will have small exophoria usually less than 10 when fully dissociated. Epidemiology Like all forms of strabismus, exotropic deviations can be manifest or latent, and if the former, intermittent or constant. Intermittent exotropia is by far the most common form of manifest XT. Exodeviations occur about one-third less frequently than esodeviations in North America and Europe and occur more frequently in the Asian population. Intermittent exotropia is more common in females with a ratio of 2:1 (F: M). Intermittent exotropia usually noticed by parents in early childhood (2-5 years). Clinical features Intermit

    Dr. Amr Mohamed · Dr. Sowmya R, MS,FMRF, FAICO
  2. Students Gallery 1 Apr 2021 16 min read

    Instruments used in Cataract Surgery: Ready Reckoner for the Post Graduates

    Cataract Surgery is the most common surgery performed all over the world. Proper knowledge of surgical instruments used in cataract surgery is essential. This article gives you an overview and description of instruments commonly used in cataract surgery. Simcoe's irrigation- aspiration cannula: Design: Available in two different designs. The original model also called the direct Simcoe where aspiration is through the silicone tube and irrigation through the main hub. The surgeon holds the syringe attached to the silicone tubing which is used to generate suction for aspiration in his/her left hand and the irrigation line is attached to the main central hub. The other model is the Reverse Simcoe where irrigation is through the main hub. The surgeon uses a syringe attached to the main hub to generate suction for aspiration. Cannulas are available in different sizes: 21,22,23 gauge which has an aspiration port size of 0.5,0.35,0.3 mm respectively. These are 15 mm long in size with an angle

    Dr. Rohit Rao
  3. Students Gallery 1 Apr 2021 27 min read

    Instruments Used in Vitreoretinal Surgery: A Comprehensive Guide for the Post Graduates

    History : While writing about the instrumentation of retinal surgery, the first name came in my mind was the none other than the Jules Gonin, who not only identified the Retinal tear as a prerequisite for the retinal detachment in the way back in 1904 in his first paper with series of 3 cases but also described the management of the same later on after constant hard work over the next two decade. He made major contribution and impact in the field of retinal surgery, immediately after his major presentation at the International Congress of Ophthalmology in 1929, and hence it is worth starting the topic recalling him. From the Gonin era to date, there were three major events in terms of development. 1st – improvement in instrumentation used to evaluate vitreoretinal pathology. 2nd – Evolution of the methods to create a chorioretinal adhesion around retinal breaks. 3rd – the development of a variety of techniques to tackle the vitreoretinal adhesion and hence to close the break permanentl

    Dr. Pratik Shah
  4. Articles 1 Apr 2021 20 min read

    Ocular Sarcoidosis: A Review for the Postgraduates

    Introduction: Sarcoidosis is a chronic multisystemic granulomatous disorder caused by an exaggerated cellular immune response to a variety of self or non-self-antigens in a genetically predisposed individual resulting in non-caseating granulomas. Ocular involvement occurs in 25-60% of systemic sarcoidosis at some point of time1. In this article, we look at the emerging literature on epidemiology, pathogenesis, clinical profile, and management in ocular sarcoidosis. Epidemiology: Sarcoidosis has an overall incidence of 6-10 per 100,000. Although sarcoidosis occurs worldwide, it is predominant in certain ethnic and racial groups like the Afro-Caribbean, Scandinavian, and Irish populations2-4. Highest incidence of ocular sarcoidosis is in the 20-40-year age group. Some studies show two peaks of incidence for ocular sarcoidosis the first at ages 20-30 and the second at ages 50-605. There is also a higher incidence of ocular involvement in women4. The reported incidence of ocular sarcoidosi

    Dr. Vinaya Kumar Konana · Dr. Kalpana Babu
  5. Articles 1 Apr 2021 8 min read

    Slit-lamp Biomicroscopy

    A slit-lamp is a binocular microscope used for eye examination using a slit-like light beam. In 1911, Allvar Gullstrand a Swedish Ophthalmologist designed table-mounted binocular eyepiece for 3-dimensional visualization of optically clear eye structures. Later Otto Henker, combined Gullstrand slit lamp with Czapski’s binocular microscope resulting in first slit lamp biomicroscope, allowing hand-free examination of an eye.1 The optical design of the Slit-Lamp Biomicroscope (SLB). Due to the miniature size of the anterior segment of the eye, we need high magnification and clarity to appreciate finer details. This can be achieved by having 2 convex lenses at the observer end (eyepiece) separated at its focal distance (astronomical telescope type alignment) and, a concave-convex combination (Galilean telescope type alignment) at the examinee’s end for further magnification of the image. Telescopic arrangements of lenses need to be focused at near, hence a plus power objective lens is fixed

    Dr. Nagesha C K · Dr. Shruthi M N
  6. Students Gallery 1 Apr 2021 57 min read

    Syndromes in Ophthalmology

    A syndrome is a recognizable complex of symptoms and physical findings that indicate a specific condition for which a direct cause is not necessarily understood. While medicine has innumerable syndromes, a similar scenario exists in ophthalmology too. It is crucial for a clinically astute ophthalmologist to be aware of these syndromes to initiate necessary workup for more sinister lesions associated with certain ocular findings. This article aims at addressing various syndromes related to ophthalmology highlighting the ocular findings. A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z A Aarskog’s syndrome: Ocular symptoms include megalocornea, hypertelorism, antimongoloid palpebral fissures. Systemic features are short stature, syndactyly. Aberfeld Syndrome Ocular features include blepharophimosis, exotropia, myopia, congenital cataracts, microcornea. Systemic features are myopathy, bone deformities, arachnodactyly, dwarfism, hypoplas

    Dr. Niranjan Karthik Senthil Kumar
  7. Articles 1 Apr 2021 43 min read

    Visual Electrophysiology Made Simple for the Postgraduates

    Visual electrophysiology is an extremely useful tool to study the retinal function objectively. It assesses the functional aspects of not only the retina but also the visual pathway as a whole. Even in this era of advanced imaging, one cannot ignore the importance of the functional aspects of the cellular network in the retina. The commonly used tests with their salient applications are enumerated in Table 1. S.no Test Application 1. Electroretinogram(ERG) Elicits mass response from the Retina 2. Electro-oculogram(EOG) Assesses the function of the Retinal pigment epithelium 3. Pattern ERG(PERG) Differentiates macular and optic nerve pathology 4. Multifocal ERG(MfERG) Picks up focal retinal pathology and maps out the topography 5. Photopic Negative Response(PhNR) Tests the function of retinal ganglion cells 6. Visual Evoked Potentials(VEP) Assesses the visual pathway up to the occipital cortex 7. Multifocal VEP(MfVEP) Picks up focal dysfunction of the visual pathway and maps the topogra

    Dr. Parveen Sen · Karthika Pandurangan · +1 other
  8. Articles 1 Apr 2021 13 min read

    A Beginner's Guide to Ultrasound Biomicroscopy

    Introduction: Anterior segment ocular imaging has gone through various inventions starting from the ultrasound in the 20th century to the recent AS- OCT.1 Ultrasound bio-microscopy, one of the ocular imaging devices is a high-resolution technique, which allows in vivo assessment of the structures of the anterior segment of the eye where cross-sectional images of ocular structures are obtained at microscopic resolution. 2The higher frequency of UBM ranging between 35 and 50 MHz, gives a depth of about 4 mm and an axial and lateral resolution of approximately 25 and 50 microns, respectively. 3 Being a non-invasive technique, efficient regardless of the clarity of the optical media and due to its portability can be performed both in adults and children with no complications.4 The internal acoustic characteristics of UBM, accompanied by the very fine backscatter speckle patterns, permit clear differentiation of ocular tissue at various levels.5 UBM imaging has been very useful in understan

    Dr. Sowkath Ali · Dr. Eunice Goh · +1 other
  9. Anatomy of eye 1 Apr 2021 21 min read

    Anatomy of Uvea

    Uvea is the middle vascular coat of the eyeball. From anterior to posterior, the uvea or uveal tract can be divided into three parts- Iris, Ciliary body, and choroid. The name “uvea” has originated from the Latin word grape. Why a grape? If the stem is removed from a grape, the hole looks like the pupil and the grape the eyeball. Iris : Iris is the anterior-most part of the uveal tract. It is a thin and circular structure which forms a diaphragm like structure in front of the crystalline lens. The word “iris” has originated from a Greek word. In Greek mythology, the iris is the name of the Greek goddess of the rainbow. The diaphragm formed by the iris contains a central aperture known as the pupil. The location of the pupil is not exactly central, its little nasal to the center. The pupil determines the amount of light entering the eye. The normal size of the pupillary aperture is 3-4 mm. Details on the pupil will be discussed in chapter "Pupil". Iris is attached to the middle of the a

    Dr. Parthopratim Dutta Majumder
  10. Articles 1 Apr 2021 30 min read

    Clinical Applications of Multicolor Imaging

    Multicolor imaging (MCI) is a non-invasive retinal imaging modality available in the Spectralis platform (Heidelberg Engineering, Heidelberg, Germany). It simultaneously acquires three reflectance images of the retina using three individual lasers of different wavelengths: blue (488 nm), green (515 nm), and infrared (820 nm). These penetrate the tissue to different depths, simultaneously capturing and depicting information originating from different retinal structures. The infrared reflectance (IR) image visualizes structures at the level of the outer retina and choroid. The green reflectance (GR) image allows imaging of retinal blood vessels, hemorrhages, and exudates. The blue reflectance (BR) particularly provides details of the inner retina and the vitreoretinal interface such as epiretinal membranes, retinal nerve fiber layer (RNFL) thinning, and macular pigment changes. The information from these three images is integrated to form a composite multicolor image.1 Color fundus photo

    Dr. Sugandha Goel · Dr. Rupak Roy

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