Lacrimal system

Cintron, C. The molecular structure of the comeal stroma in health and disease. In Chandler, J.W., Sugar, J., Edelhauser, H.F. (eds.) External Diseases Cornea, Conjonctiva, Sclere, Eyehds, Lacrimal System, vol. 8. Mosby, London (1994)... 

Topical ocular fluorescein can be used to evaluate two key aspects of the lacrimal system.These are the stability of the precorneal tear film and the patency of the lacrimal drainage system. 

Bergin DJ. Anatomy of the eyelids, lacrimal system and orbit. In McCord CD,Tanenbaum M, eds. Oculoplastic surgery, ed. 2. New York Raven Press, 1987. 

Diseases and disorders involving the lacrimal system are among the more common conditions experienced by ophthalmic patients, with as many as 25% complaining of dry eye symptoms alone.The lacrimal system is most easily considered as having three components—the secretory system, the distribution system, and the excretory or drainage system.These components must work in harmony to support a healthy, moist, and comfortable ocular surfece. 

A healthy lacrimal system is necessary for ocular comfort, resistance to disease and exposure, corneal oxygenation, and optimal visual function. A careful patient history and examination is necessary to arrive at an accurate diagnosis, which directs appropriate management. 

Figure 24-1 Schematic view of the lacrimal system.The lacrimal gland supplies aqueous (reflex) secretions. Arrows indicate the pathway that tears follow to drainage, beginning at the punctum. The area enclosed by dashed lines represents the drainage apparatus. (Adapted from BoteUio SY Tears and the lacrimal gland. Sci Am 1964 211 78-85. Copyright 1964 by Scientific American, Inc. AU rights reserved.)...

Figure 24-5 Dynamics of tear flow. (From Kanski JJ. Clinical ophthalmology. Reprinted in Melroe. Evaluation of the lacrimal system. In Roberts and Terry eds. Ocular disease diagnosis and treatment, ed 2. Edinburgh Butterworth-Heinemann, 1996.)...

If a significant inflammatory component or a response to bacterial exotoxin hypersensitivity in the fiarm of marginal corneal infiltrates or phlyctenules is present, treatment may require concurrent topical steroid therapy. When chronic dacryocystitis is involved, treatment should include irrigation of the lacrimal system with trimethoprim-polymyxin B or gentamicin. Adjunctive systemic antibiotic therapy may also be required (see Chapter 24). 

This chapter provides practical imormation regarding common corneal conditions that may require treatment. By nature of its anatomic proximity to and integration with other ocular and adnexal strnctnres, corneal abnormalities may result from diseases primary to the eyelids, conjunctiva, lacrimal system, episclera, and other tissues. The details of these conditions are not emphasized in this chapter thus the reader should refer to other appropriate chapters for this imormation. 

Figure 7 Anatomical view of the lids and lacrimal systems.

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