Ophthalmology

Astigmatism is a common refractive error caused by irregular curvature of the cornea or lens, leading to blurred or distorted vision. It can occur alongside myopia or hyperopia and may be congenital, acquired from eye injury, surgery, or conditions like keratoconus, with a possible genetic predisposition. Symptoms include blurred vision at all distances, eye strain, headaches, squinting, and difficulty seeing at night. Diagnosis involves visual acuity testing, keratometry, corneal topography, and refraction assessment. Management includes corrective lenses or refractive surgery in selected cases.

Conjunctivitis is inflammation or infection of the conjunctiva, the clear membrane covering the white part of the eye. It can be caused by bacteria, viruses, or allergens. Common risk factors include infections like adenovirus, allergies to pollen or dust, contact lens irritation, and environmental irritants such as smoke or chlorine. Symptoms include redness, tearing, itching, burning, sticky discharge, and morning eyelash crusting. Diagnosis is primarily clinical, with swabs or cultures in severe cases. Management involves hygiene, avoiding eye rubbing, and using prescribed eye drops.

A corneal abrasion is a superficial scratch or injury to the cornea, often caused by trauma or a foreign body in the eye. Common risk factors include dust, sand, fingernail injuries, improper contact lens use, and rubbing the eye when debris is present. Symptoms include sudden eye pain, tearing, light sensitivity, foreign body sensation, redness, and blurred vision. Diagnosis is made using fluorescein dye and slit-lamp examination. Prompt care prevents infection, corneal ulceration, scarring, and potential permanent vision loss.

Keratitis is an infection of the cornea caused by bacteria, fungi, viruses, or parasites, and can threaten vision if untreated. Risk factors include contact lens overuse or poor hygiene, eye trauma, corneal abrasion, immunosuppression, and pre-existing ocular surface disease. Symptoms include severe eye pain, redness, blurred vision, light sensitivity, discharge, and a visible white corneal spot. Diagnosis involves slit-lamp examination, fluorescein staining, corneal scraping for culture, and PCR testing for viral causes. Management focuses on prompt antimicrobial therapy and preventive hygiene measures.

Contact lens removal is the process of safely taking out soft, rigid, or scleral contact lenses, either by the patient or a clinician. It is performed routinely for lens replacement, in cases of discomfort, when a lens is stuck, or before ocular procedures. Soft lenses are typically removed manually, while rigid or scleral lenses may require specialised techniques or instruments. A slit-lamp exam may be done if removal is difficult or corneal injury is suspected. Post-removal care includes inspecting the cornea and advising proper lens hygiene to prevent complications.

Corneal scraping is a diagnostic procedure performed to obtain superficial material from the cornea for microscopy, culture, and sensitivity testing when an infection is suspected. It is used to identify causative organisms in infectious keratitis, including bacterial, fungal, or Acanthamoeba infections, to guide targeted therapy. The procedure is performed under topical anaesthesia at the slit lamp or in a sterile theatre using a blade or spatula to scrape the affected area. Samples are placed on slides and culture media, and treatment begins promptly based on preliminary or culture results.

Diabetic retinopathy screening is a preventive eye examination for people with diabetes, aiming to detect early retinal changes before vision loss occurs. The procedure typically involves a dilated fundus examination or retinal photography using a non-mydriatic camera. Images are analysed for signs of microaneurysms, haemorrhages, or macular oedema. Advanced imaging, like OCT or fluorescein angiography, may be used if needed. Early detection allows timely interventions, such as laser therapy, anti-VEGF injections, or surgery, to prevent progression of diabetic eye disease and preserve vision.

A dilated fundus examination is a detailed evaluation of the retina, optic nerve, and vitreous after pharmacologic pupil dilation. Using indirect ophthalmoscopy or a slit-lamp with a fundus lens, the procedure allows eye specialists to detect and monitor conditions affecting the back of the eye. It is essential for identifying diabetic retinopathy, glaucoma, macular disease, retinal tears, or detachments, as well as assessing systemic diseases that affect the eyes. Imaging modalities such as OCT, fundus photography, or fluorescein angiography may complement the exam for accurate diagnosis.