Cornea

1–10 of 36 articles Page 1 of 4

All Cornea 36 Cataract 17 Glaucoma 14 Retina & Vitreous 72 Neurophthalmology 8 Oculoplasty 15 Uvea & Inflammatory Diseases 24 Miscellaneous 20 Oncology 9 Pediatric Ophthalmology 16

11 min read

Iris Repair Techniques

Trauma to the iris can present in various ways depending on its severity and location. Tear at the iris root leads to Iridodialysis, while tears at the pupillary border can damage the sphincter muscle, leading to a partially reactive, atonic or Mydriatic pupil. Tears can be full thickness or partial thickness. Full thickness defect involves the iris stroma and partial thickness involves only the posterior pigment epithelium leading to trans-illumination defects. Traumatic Iridodialysis Traumatic Mydriasis Etiology of iris defects: Iris defects can be a consequence of either: Congenital (iris coloboma) Acquired Iatrogenic (iris lesion removal) Traumatic (traumatic mydriasis or injury resulting in pupil irregularity or muscle tear) Complicated intraocular surgery (can cause dialysis, atonic dilated pupil or iris tissue loss and injury) Symptoms: Patients with photic symptoms due to iris defects complain of: Glare, Haloes in bright light conditions, Diplopia, and Trouble reading Patients

Dr. Hema Joshi · Dr. Sasmita Sanghai
7 min read

Ten Facts Every Ophthalmologist Should Know About Lubricating Eye Drops

Introduction Artificial tear substitutes lubricate and protect the ocular surface and provide relief from ocular dryness, irritation, and burning sensation. They play a major role in providing symptomatic relief and are widely used for all types of dry eye diseases and nonspecific causes of ocular fatigue as well. Choosing the right kind of lubricating drops is of utmost importance. A number of reasons including lifestyle changes, increased computer and digital screen usage, and awareness of dry eye have resulted in an increase in the utilization of these eye drops. It is important to understand a few simple features of these drops to optimize their beneficial effects.[1] Commercially available lubricating eye drops have varying composition, viscosity, duration of action, preservatives, osmolarity, and pH. This article discusses the composition of tear substitutes and the mechanism of action on the ocular surface. 1. Role of lubricating eye drops on the ocular surface The main purpose

Dr. Sharon DSouza · FCE
7 min read

Corneal Ulcer Simplified for the Postgraduates: Ten Points

An ulcer is a breach in the continuity of corneal epithelial. However, a corneal ulcer is an epithelial breach with superficial tissue loss (subepithelial or stroma) having variable grades of inflammation. The causes can be infectious (bacterial, fungal, viral, Pythium) and autoimmune (marginal keratitis, peripheral ulcerative keratitis). Here, we discuss ten essential clinical key points for diagnosing a corneal ulcer. 1. History A detailed and meticulous history is essential in each case. The patients commonly present with pain, redness, photophobia, and defective vision. The history of trauma (vegetative matter, stick, mud, clay, insect bite, etc.), onset, presentation, and progression should be noted. Sudden onset and rapid progression are associated with Pseudomonas, Pneumococcus, and Staphylococcus ulcers. Gradual onset and slow progression are seen in Acanthamoeba, Nocardia, and Mycobacterium. A detailed history of ocular (Contact lens, adnexal infections, ocular surface disease

Dr. Bharat Gurnani · FCRS · +1 other
11 min read

i-File: Pseudophakic Bullous Keratopathy

A 60-year-old-male presented to the Cornea clinic with diminution of vision in the left eye for 4 months which was associated with intermittent photophobia and colored haloes around lights, especially on waking up in the morning. The patient also complains of pain and watering. No history of associated redness, itching, or discharge. Past Ocular History: H/o OD cataract surgery 6 years, OS cataract surgery 4 months back. No h/o trauma. Past Medical History/ History of Medication: No significant systemic history could be elicited. The patient was not on any medication. No addictions. Family History: No significant family history found Review of Systems/Systemic Examination: Systemic examination was within normal limits. All vitals were within normal limits. OCULAR EXAMINATION Best Corrected Visual Acuity (Snellen) Right eye (OD): 6/9 Left eye (OS): CF 2 m Ocular Motility/Alignment - Full, free, and painless in all gazes Intraocular Pressure (IOP) OD: 18 mm of Hg OS: 14 mm of Hg Pupils-

Dr. Hema Joshi · Dr. Akhilesh Yadav
19 min read

Basics of limbal Stem Cell Deficiency for the Postgraduates

Limbal Epithelial Stem Cells Anatomy: The healthy corneo-scleral limbus (Figure 1) is a gradual transition zone from the stratified, non- keratinised squamous epithelium of the cornea to the stratified, non- keratinised columnar epithelium with mucin-secreting goblet cells of the conjunctiva. It has 7-10 layers of cells, which have attachments similar to the corneal cells. Figure 1: Slit-lamp photograph (high magnification) of the normal limbus showing arrangement of pigmentated Palisades of Vogt in the inferior quadrant. This zone contains limbal epithelial stem cells (LSCs) that generate new epithelial cells during homeostasis and after injury or insult, to maintain corneal transparency and vision. LSCs are believed to be located within the basal layer of limbal crypts (in the palisades of Vogt) [1] and focal stromal projections (finger-like projections of stroma containing a central blood vessel, and extend upward into the corneal limbal epithelium and are surrounded by small, tight

Dr. Purvasha Narang
10 min read

How to Present a Case of Corneal Ulcer in the Examination

1. Obtain a detailed history : a. A history of injury and the injuring agent - some pointers from this would be the occurrence of fungal infections in injuries with vegetable matter/insect wing cases; bacillus infections in patients with broomstick injuries; gram-positive infections with metal foreign bodies and so on b. A history of past such similar episodes - typically, this suggests the possibility of viral infections c. History of contact lens use - in such cases, while there is the possibility of a sterile infiltrate, especially if such infiltrates are present at 3 and 9 o? clock periphery, it is imperative to keep in mind serious infections such as pseudomonas d. Prior treatment history - obtain a detailed history of the name of antibiotic used, the frequency of use suggested, and the compliance of the patient with therapy. Failure to respond to adequate dose and duration of appropriate antibiotics suggests the possibility of a fungal or parasitic infection. e. Pain, discharge,

Dr. Srinivas K Rao
12 min read

Pterygium: A Review

Introduction A pterygium is a fibrovascular, wing-shaped encroachment of the conjunctiva onto the cornea, usually in the horizontal meridian of the palpebral fissure. Histopathology shows hyaline degeneration with elastotic proliferation. Risk factors Exposure to ultraviolet light and environmental microtrauma to the ocular surface is thought to predispose to pterygium formation. A localized limbal stem cell dysfunction, possibly related to ultraviolet induced damage and a genetic predisposition has also been postulated. Pathogenesis Pterygium pathogenesis can be considered as occurring in two stages: the initial disruption of the limbal corneal-conjunctival epithelial barrier, and the progressive “conjunctivalization” of the cornea characterized by cellular proliferation, inflammation, connective tissue remodeling, and angiogenesis Morphology Head—the part which rests on the cornea Neck— constricted portion seen at the limbus Body – remaining bulk of mass Cap—a semilunar infiltrating

Dr. Ramya Subramaniam · Dr. Srinivas K Rao
12 min read

Keratoconus

Introduction: Keratoconus is a degenerative non-inflammatory disease of the cornea. It presents generally at puberty with progressive corneal steepening & thinning, most typically inferior to the center of the cornea. Keratoconus is characterized by progressive Myopia, both regular and irregular astigmatism in mild cases and vision compromising ectasia in advanced disease. It is usually bilateral and asymmetrical. The incidence of keratoconus is 1 in 2000. Patients often present with complaints of distorted, blurred vision, glare, light sensitivity and history of frequent change of glasses. PATHOGENESIS: Despite extensive research the etiology and exact pathogenesis of keratoconus is still not clearly established. It has been associated with atopic disease and chronic eye rubbing like in patients with Down’s Syndrome & Atopic dermatitis. There has been a possibility of genetic and hereditary disposition. It has been associated with systemic diseases like the Ehler-Danlos syndrome, oste

Dr. Sujatha Mohan
30 min read

Anterior Segment Optical Coherence Tomography in Diseases Of The Ocular Surface And Cornea

I. Introduction : Anterior segment optical coherence tomography (ASOCT) is a sophisticated non-contact imaging device that produces high-resolution images for detailed assessment of the structures of the ocular surface and anterior chamber in various disease conditions. Starting from the earlier generation time-domain devices first described in 1991 by Huang et al [1] to the current Fourier-domain OCT devices, the technological advancement in this device has improved the diagnostic ability tremendously. This imaging modality has evolved into a highly precise tool for clinical diagnosis and management as well as in research and understanding disease pathology. In this review, we describe the evolution of ASOCT, its technology in brief and focus on highlighting the various clinical applications with examples. While Izzat et al first introduced the use of AS-OCT for imaging the anterior segment of the eye [2], it is well known that the OCT initially evolved as a tool for retinal imaging.

Dr. Supriya Sharma · Dr. Somasheila Murthy
21 min read

Complications of Penetrating Keratoplasty

Penetrating keratoplasty (PK) is a procedure in which full-thickness host corneal tissue is replaced with donor corneal tissue. Objectives of PK maybe Optical-to establish a clear visual axis or to minimize refractive error in severely distorted corneas Tectonic-to provide structural integrity Therapeutic-to eliminate infection Occasionally for cosmoses Complications of PK may be divided as intraoperative, early postoperative, and late postoperative. Intra-operative complications: Intra-operative complications may occur at each step of the surgery. These complications can be avoided with meticulous pre-operative planning and careful attention at each step. 1. Anaesthesia: In the case of the retrobulbar or peri-bulbar block (1), globe perforation may occur. A meticulous pre-operative assessment could avoid this complication as eyes with a posterior staphyloma possess a higher risk of perforation. A retrobulbar block may cause scleral perforation, orbital hemorrhage, optic nerve trauma,

Dr. Bhupesh P Jain · Dr. Priyanka Kashelkar