Basal tear secretion

The device is generally comfortable and well accepted by many patients, but its use does have certain disadvantages. Some patients have problems with discomfort (foreign body sensation) or expulsion of the Lacrisert.The insert can be wetted with saline before insertion to improve comfort, but this can make even more difficult the insert s placement into the lower cul-de-sac, which requires a moderate amount of dexterity. Supplementation with artificial tears after insertion may improve comfort. The most common patient complaint is blurred vision associated with the intense release of polymer during the first 4 to 6 hours after instillation, from a thickened tear film.Adding such fluid as drops of NaCl 0.9% or artificial tear solution can reduce the tear film viscosity and minimize the visual complaints. As the insert dissolves it releases debris that can blur vision and cause irritation. Most patients with mild signs and symptoms of dry eye do not experience improvement with use of the insert, as compared with the use of conventional tear solutions. Because some tear secretion is necessary to dissolve the Lacrisert, KCS patients with low basal tear secretion may not benefit from or tolerate its use. 

The Schirmer II test can be performed in extremely dry eyes with very low results on Schirmer I. Before removing the paper strips at the conclusion of the Schirmer I test, a cotton swab is inserted into the nose to mechanically irritate the nasal mucosa. In normal subjects this stimulates an impressive basal tear secretion. If this response is present, ocular surface disease that has interfered with the normal neurologic feedback mechanism is suspected of contributing to the dry eye state. If the response is absent, lacrimal gland dysfunction is the likely cause. 

Basal plus Basic tearing) Basic secretion test (with anesthetic) <10 mm wetting in 10 minutes >15 mm wetting in 5 minutes <5 mm wetting in 5 minutes Strongly suggestive of hyposecretion disorder No conclusions need further evaluation Basal tear secretion deficit... 

Sensory systems Eyes Conjunctival epithelial cells, basal tear secretion, and tear quality were markedly affected in patients during treatment with isotretinoin 0.8 mg/ kg [40 ]. Ocular adverse effects of isotretinoin are generally not serious and resolve after withdrawal. 

A number of ocular surface disorders collectively termed as Dry Eye Syndromes have also been associated with the conjunctiva. For example, a deficiency and/or imbalance in compositions of the tear film is often found on the ocular surface during keratoconjunctivitis sicca. Since the conjunctiva plays a direct role in the maintenance of the tear fluid stability via secretion of mucin [1] by its resident goblet cells [4] and basal fluid secretion driven by electro-osmotic gradients across the tissue [3], the conjunctiva is a well deserved, but not intensively studied, target of interest in research efforts aimed against combating Dry Eye Syndromes. 

Schirmer I tear flow test (basal secretion measurement)... 

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