Ophthalmology Terminology V
Valsalva Retinopathy. Hemorrhages that occur infront of the the macular area,between the retina and vitreous humor, due to rupture of small blood vessels in the perimacular area. This rupture associated with sudden rise in the intravenous pressure due to valsalva maneuver.
Vernal keratoconjunctivitis. Type of allergic conjunctivitis which occurs on a seasonal basis. It occurs mainly in children and in boys more than girls. Patients can have systemic allergic conditions such as asthma and eczema.
Viscoelastic Material. Special material that exhibits the properties of both viscosity and elasticity. It is used mainly during cataract surgery to maintain the depth of the anterior chamber and also to protect the endothelial layer of the cornea from heat that is generated from high Ultrasound rate of Phaco probe.
Visual Acuity. Clearness of vision.
Visual Adaptation. The ability of the person to adapt his vision in dark and in light environment.
Visual Cortex. Part of the brain which is responsible for vision. It presents in the occipital part of the brain.
Visual Evoked Potential. Special instrument that is used to measure the potentials generated at the visual part of the brain during visual stimuli.
Visual Field. Total area that is perceived simultaneously by the fixating eye.
Visual Hallunication. It is a visual perception without retinal stimulus.
Vitrectomy. Surgical procedure in which the vitreous body is removed.
Vitreous Body. A transparent,gel like material that occupies the posterior part of the eye. It is attached to the retina, optic disc and back surface of the lens.
Vitreous Hemorrhage. Bleeding in the vitreous body.
Vitreous Tap. A procedure in which sample of the vitreous is aspirated with 23G needle under sterile condition in the operating room. This sample will be taken for culture and analysis. It is mainly done in patients with endophthalmitis.
Vogt limbal girdle. A common type of corneal degeneration that is age related and occurs in both eyes.It is characterized by peripheral corneal opacities that occur in interpalpebral area.
Vogt Koyanagi Harada Syndrome. Autoimmune disease that occurs against melanocytes. These cells present in eye,ear, skin and meninges.
Vortex Keratopathy. Whorl like pattern of deposits in the epithelial layer of the cornea. It usually arises from a point and radiate to the periphery of the cornea. It is caused by medications such as chloroquine and amiodarone.