nasolacrimal duct obstruction
Introduction
Introduction Obstruction (or stenosis) of the lacrimal duct refers to the beginning of the lacrimal duct (thoracic tear ductlet lacrimal duct). The narrow diameter of the tube is superficial and is connected to the conjunctival sac. It is easy to be thanked by the impact of the inflammatory injury and the lower end of the nasolacrimal duct. It is also an anatomical stenosis that is susceptible to obstruction due to the indifference of nasal lesions.
Cause
Cause
The reasons are: congenital malformation, mainly occurs in the lower mouth of the nasolacrimal duct; trauma; dacryocystitis or inflammation around the lacrimal sac; tumor around the lacrimal sac or lacrimal sac; foreign body; obstruction of the nasolacrimal duct; scar after nasal surgery. The nasal opening of the lower end of the nasolacrimal duct was closed by congenital membrane tissue, and the membrane tissue was still not broken about 4 weeks after birth.
Examine
an examination
Related inspection
Nasal endoscopy, otolaryngology, CT examination
Clinically, patients with nasolacrimal duct obstruction should be examined:
First, physical examination
Taking a medical history gives us a first impression and revelation, and also guides us to a concept of the nature of the disease.
Second, laboratory inspection
Laboratory examinations must be summarized and analyzed based on objective data learned from medical history and physical examination, from which several diagnostic possibilities may be proposed, and further consideration should be given to those examinations to confirm the diagnosis. Such as: nasal endoscopy, MRI of the nasopharynx, CT examination of the ear, nose and throat.
Diagnosis
Differential diagnosis
Neonatal dacryocystitis is due to the absence of degeneration of the residual embryonic membrane at the lower end of the nasolacrimal duct, obstructing the lower end of the nasolacrimal duct, and tears and bacteria remaining in the lacrimal sac, causing secondary infection. About 2 to 4% of full-term infants may have such residual membrane obstruction, but most of the residual membranes are expected to self-shrink and regain patency within 4 to 6 weeks after birth. It is rare due to dysplasia and stenosis of the nasolacrimal duct.
