B Dacryocystorhinostomy
Dacryocystorhinostomy is performed for patients who have chronic tearing or obstruction at the level of the nasolacrimal duct. This procedure restores drainage into the nose from the lacrimal sac. The surgeon injects lidocaine 1% with 1:100,000 epinephrine, bupivacaine (Marcaine) 0.75%, and hyaluronidase (Wydase) in the operative site along the lacrimal crest. An additional injection may be given along the medial orbital wall, anesthetizing the ethmoidal nerve. This block may cause a temporary dilated pupil or medial rectus muscle paralysis.
A small incision is made near the medial canthus to allow a subperiosteal dissection to the lacrimal sac. The bone between the lacrimal fossa and middle fossa is broken and cut, making a small canaliculi. The mucosa of the lacrimal sac is anastomosed to the mucosa of the nose. To prevent closure of the newly formed path by scarring, a silicone tube may be placed inside the duct. Muscles and tissues in the area are then closed. The patient is then asked to open the eyelids, and when the proper height is obtained, the incision is closed.
2. Preoperative assessment and patient preparation
a) History and physical examination: This procedure may be done in patients of varying age. The patient’s cardiac history should be determined because epinephrine is to be used for vasoconstriction. Infections in the surgical area should be treated with antibiotics for several days before surgery. Because of the inaccessibility of the anesthesia provider to the head, patients with obstructive sleep apnea (OSA) should also be identified and anesthesia planned accordingly.