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Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
In Dacryocystorhinostomy, opening is done into which of the following nasal cavity meatus?
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The correct answer is  Dacryocystorhinostomy is performed to assist in the drainage of tears and secretions from the lacrimal sac into the middle meatus of the nose by forming a sho circuit through the lacrimal bone and the nasal mucosa. This procedure is performed when the nasolacrimal duct is obstructed by fibrous tissue or bone and has become impermeable in order to establish a new communication pathway between the lacrimal sac and nose. The nasolacrimal duct is about 18mm long. It passes inferiorly, posteriorly and laterally to open into the inferior nasal meatus. Opening of the duct is covered by a mucosal fold(valve of Hasner).