a
How do you perform dacryocystorhinostomy (DCR)?

Answer
The following steps are involved in DCR:
1. General anaesthesia.
2. Nasal packing soaked in 4% cocaine is inserted into the involved side to reduce bleeding.
3. The skin around the medial canthus is infiltrated with local anaesthesia 
containing adrenaline to reduce bleeding. A skin incision is made slightly below the medial canthal tendon and extended downward and slightly outward for approximately 25 mm.
4. The incision is extended by sharp and blunt dissection to the underlying 
periosteum of the frontal process of the maxilla and the anterior lacrimal crest.
5. The angular vessels are retracted or ligated as required.
6. A subperiosteal dissection is performed posteriorly over the lacrimal groove as far posterior as the posterior lacrimal crest and inferiorly to the nasolacrimal canal. This can be achieved using a Rollet periosteal elevator.
7. Osteotomy is created by first dislocating the lacrimo-maxillary suture using a Traquair's periosteal elevator. Kerrison punch is then used to increase the osteotomy. 
8. The nasal mucosa is separated from the bone with each bite using the Traquair's elevator. The bony opening is enlarged to a diameter of 15-20 mm.
9. The lacrimal sac is incised vertically and then horizontally to create an anterior and a posterior flap.
10. The nasal mucosa is also incised vertically and then horizontally to form anterior and posterior flap.
11. The posterior nasal flap is sutured to the posterior flap of the lacrimal sac. If tubing is required, it should be inserted now.
12. The anterior flaps are sutured. 
13. The medial canthal tendon is resutured (some surgeons may leave this) and the skin sutured.

The following is a set of instruments used in lacrimal system surgery. Click the picture for questions.