Nasolacrimal duct obstruction is the obstruction of the nasolacrimal duct and may be either congenital or acquired. Obstruction of the nasolacrimal duct leads to the excess overflow of tears called epiphora. Sign and symptoms
Excessive tearing is the most common complaint of patients with nasolacrimal duct obstruction, followed by acute or chronic infections. Pain at the side of the nose suggests dacryocystitis. Nasolacrimal duct obstruction is more common with increasing age and more common in females than males. Cause
Involutional stenosis
Involutional stenosis is probably the most common cause of nasolacrimal duct obstruction in older people. It affects women twice as frequently as men. Although the inciting event in this process is unknown, clinicopathologic study suggests that compression of the lumen of the nasolacrimal duct is caused by inflammatory infiltrates and edema. This may be the result of an unidentified infection or possibly an autoimmune disease. Dacryolith
Dacryoliths or cast formation, within the lacrimal sac can also produce obstruction of the nasolacrimal duct. Sinus disease
Sinus disease often occurs in conjunction with, and in other instances may contribute to the development of nasolacrimal duct obstruction. Patients should be asked about previous sinus surgery, as the nasolacrimal duct is sometimes damaged when the maxillary sinus ostium is being enlarged anteriorly. Trauma
Naso-orbital fractures may involve the nasolacrimal duct. Early treatment by fracture reduction with stenting of the entire lacrimal drainage system should be considered. However, such injuries are often not recognized or are initially neglected as more serious injuries are managed. In such cases, late treatment of persistent epiphora usually requires dacryocystorhinostomy.
DTaP-IPV-HepB vaccine is a combination vaccine whose generic name is diphtheria and tetanus toxoids and acellular pertussis adsorbed, hepatitis B (recombinant) and inactivated polio vaccine or DTaP-IPV-Hep B. It protects against the infectious diseases diphtheria, tetanus, pertussis, poliomyelitis, and hepatitis B.A branded formulation is marketed in the U.S. as Pediarix by GlaxoSmithKline. == References ==