Corneal sensitivity

Cornea - Decreased corneal sensitivity punctate to lineal opacities transient edema. 

Ophthalmic Ocular irritation including conjunctivitis blepharitis keratitis blepharoptosis decreased corneal sensitivity visual disturbances including refractive changes diplopia ptosis. 

Even though cyclodextrins drug complexes seem to decrease ocular toxicity of irritant drugs, cyclodextrins themselves may exhibit ocular toxicity and should therefore be screened by performing corneal sensitivity studies. Among all cyclodextrin derivates investigated, hydroxy-propyl-P-cyclodextrin showed the most favorable properties in terms of toxicity [1],... 

The efficacy of topical ocular anesthetics is usually determined by their ability to suppress corneal sensitivity When a dose-response relationship is determined for various anesthetics, a concentration for each drug is obtained beyond which no further increase in activity occurs. The concentration at which this maximum efficacy occurs is termed the maximum effective concentra-tion.Uhns, increasing the concentration of the anesthetic beyond the maximum effective concentration serves no useful purpose but increases the risk of local and systemic toxicity... 

The ability of P-blockers to stabilize membrane excitability has been exploited therapeutically in the treatment of selected cardiac arrhythmias. However, when these agents are given topically, such a property can induce corneal anesthesia. Significant decreases in corneal sensitivity... 

BourcierT, Acosta M, Borderie Y, et al. Decreased corneal sensitivity in patients with dry eye. Invest Ophthalmol Vis Sci 2005 46 2341-2345. 

The lesions are often slightly raised and stain variably with NaFl and rose bengal. They come and go and change locations quickly. The eye usually is white with little, if any, accompanying conjunctival reaction. Corneal sensitivity may be reduced or normal. 

Symptoms associated with the corneal opacities can range from mild light sensitivity to frank photophobia. Corneal sensitivity, however, is unaffected. In general, the only possible OADRs of this drug that might vrarrant discontinuation are optic neuritis and intracranial hypertension (see Appendix 35-1). 

Aragona P, Tripodi G, Spinella R, Lagana E, Ferreri G. The effects of the topical administration of non-steroidal antiinflammatory drugs on corneal epithelium and corneal sensitivity in normal subjects. Eye 2000 14(Pt 2) 206-10. 

Blindness, hearing loss, corneal sensitivity, visual disturbances Oily skin, skin and mucous membrane irritation, chronic cough... 

It is a sterile rod-shaped device made up of hydroxypropyl cellulose without any preservative used for the treatment of moderate to severe dry eye conditions, especially in patients who do not respond to other medicines. It is also used to treat other eye conditions, including corneal inflammation exposure, decreased corneal sensitivity, and repeated corneal exposures. The Lacisert insert is an eye lubricant. It works by providing tear-like lubrication for the relief of dry eyes and eye irritation. 

Hydroxypropyl cellulose (HPC) is used for the preparation of artificial tears, treat medical conditions characterized by insufficient tear production such as kerotoconjunctivitis sicca, recurrent corneal erosions, decreased corneal sensitivity, exposure, and neuroparalytic keratitis. It is also used as a disintegrant and a binder in tablets, sieving matrix for DNA separations by capillary and microchip electrophoresis and lubricant for artificial eyes, food additive, thickener, and as an emulsion stabilizer [111, 112]. 

Anatomical characteristics and physiological mechanisms protect the eye against toxic external effects. These mechanisms include the specific structure of the cornea, blinking, baseline and reflex lachiymation, drainage, tear film composition and the corneal sensitivity. The combination of aU mechanistic, anatomical and physiological characteristics maintains the integrity of the eye, together... 

AESTHESIOMETRY- AZELASTINE EYE DROPS REDUCE CORNEAL SENSITIVITY IN RABBITS, BUT NOT IN DOGS AND HUMANS... 

Therefore, in the present studies measurement of the corneal sensitivity was performed with the Cochet-Bonnet aesthesiometer in experimental animals as well as in humans. The aim was to detect anesthetizing properties of Azelastine Eye Drop solutions and to evaluate the relevance for the treatment in man. 

For the measurement of the corneal sensitivity in experimental animals the tip of the nylon filament was slowly applied perpendicularly to the central cornea until the filament bent slightly. The examination was started at the longest filament length of 60 mm. Then the filament length was shortened in 5 mm increments until a blink response occurred on at least 3 of 5 trials. The longest filament length sufficient to elicit a blink response consistently was recorded as corneal sensitivity. If even at a filament length of only 5 mm no blink reflex could be induced, a complete loss of sensitivity respectively an anesthesia of the cornea was assumed. 

As in experimental animals also in human volunteers the Cochet-Bonnet aesthesiometer was used. The sensation was measured in the inferior cornea at the 6 o clock position. The quantification of the corneal sensitivity was achieved by determination of the length of the fibre, which was necessary to provoke a notification from the subject. The corresponding pressure in g/mm was recorded. 

The contralateral eye remained untreated as control. Measurements of the corneal sensitivity were performed before treatment as well as 1,5, 10,15, 20,25, 30,40, 50, 60,70, and 80 minutes after the treatment. Additionally Azelastine ophthalmic solutions with concentrations of 0.05% or 0.1% were tested after single application in pigmented Fauve de Bourgogne rabbits. 

During measurement of the corneal sensitivity with the Cochet-Bonnet aesthesiometer in both albino and pigmented rabbits the pressure base values for untreated, physiological saline solution treated, or vehicle solution treated animals was approximately 5 g/mm. In Beagle dogs the mean pressure to elicit a blink reflex was higher than in rabbits and reached approximately 9 g/mm. In human volunteers, where the subjective notification of the touch of the filament tip on the cornea was taken as criterion, pressure base values were much lower than in experimental animals, i.e. approximately 1 g/mm. ... 

A single exposure of the eye to pepper spray is considered harmless, but repeated exposure can result in long-lasting changes in corneal sensitivity, although with no lasting decrease in visual acuity. Allergic reactions or contact dermatitis may occur on repeated exposure. 

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