Ketonuria is a medical condition in which ketone bodies are present in the urine. It is seen in conditions in which the body produces excess ketones as an alternative source of energy. It is seen during starvation or more commonly…
Glomerulonephritis, also known as glomerular nephritis, abbreviated GN, is a renal disease characterized by inflammation of the glomeruli, or small blood vessels in the kidneys.[1] It may present with isolated hematuria and/or proteinuria (blood resp. protein in the urine); or…
Glomerulonephritis, also known as glomerular nephritis, abbreviated GN, is a renal disease characterized by inflammation of the glomeruli, or small blood vessels in the kidneys.[1] It may present with isolated hematuria and/or proteinuria (blood resp. protein in the urine); or…
A urethral stricture is a narrowing of the urethra[1] caused by injury or disease such as urinary tract infections or other forms of urethritis. Presentation During the early stages of the condition, the subject may experience pain during urination and…
Blindness is the condition of lacking visual perception due to physiological or neurological factors. Various scales have been developed to describe the extent of vision loss and define “blindness.”[1] Total blindness is the complete lack of form and visual light…
Blepharitis (pronounced /bl?f?r?a?t?s/) is an ocular disease characterized by inflammation of the eyelid margins. Blepharitis may cause redness of the eyes, itching and irritation of the eyelids in one or both eyes. Its appearance is often confused with conjunctivitis and…
An optical system with astigmatism is one where rays that propagate in two perpendicular planes have different foci. If an optical system with astigmatism is used to form an image of a cross, the vertical and horizontal lines will be…
Asthenopia (aesthenopia) or eye strain is an ophthalmological condition that manifests itself through nonspecific symptoms such as fatigue, red eyes, eye strain, pain in or around the eyes, blurred vision, headache and occasional double vision. Symptoms often occur after reading,…
Amblyopia, otherwise known as lazy eye,[1] is a disorder of the visual system that is characterized by poor or indistinct vision in an eye that is otherwise physically normal, or out of proportion to associated structural abnormalities. It has been…
Amaurosis (Greek meaning darkening, dark, or obscure) is vision loss or weakness that occurs without an apparent lesion affecting the eye [1]. It may result from either a medical condition or from excess acceleration, as in flight. The term is…