**6. Surgical technique**

Dacryocystorhinostomy can be performed both externally and as an endoscopic approach. The external approach is commonly done by ophthalmologists. In external approach, an incision is made between the medial canthus and the nasal dorsum. Then the lacrimal sac is exposed and elevated from the lacrimal fossa. The lacrimal bone with an almost diameter of 1 cm is drilled. Hence, two anterior and posterior lacrimal flaps are created which are sutured to the flaps made from nasal mucosa. Finally, two silicone tubes (Budkin's tubes) are passed through the superior and inferior canaliculi and fixed in the nose.

The endoscopic approach, however, has gained much attention among ENT surgeons. Endoscopic DCR can be performed under either local or general anesthesia. It is recommended to have a video camera attached to the endoscope so that the assistant surgeon can observe the maneuvers on a video monitor.

The patient is placed in a supine position with the head slightly elevated to decrease the venous pressure at the operation site. To decongest the mucosa, vasoconstrictors are applied through pledgets in the nose. Then, injections composing of 1% lidocaine and 1:100000 epinephrine must be performed. Usually, superior to the axilla and anterior to the uncinate process are injected.

Sometimes, an endoscopic septoplasty is needed to reduce the complexity of the procedure11, 12. If required, appropriate injections in the septum must be done, too. The septoplasty is usually limited and just the superior and anterior portions of the bony septum are corrected.

Endoscopic Dacryocystorhinostomy 57

The next step would be checking the lacrimal puncta and dilating them by a probe if required. A sinus endoscope would be helpful for lighting the region. By passing the

Then the mucosal flap is positioned to approximate nasal mucosa to the lacrimal mucosa. The common canaliculus should be visible in the lateral sac wall. Then, stenting of the system would be done. If the lacrimal probes pass easily without any resistance in the canaliculus and the common canaliculus valve of Rosenmuller, lacrimal probes need not be placed. However, if there is tightness of common canaliculus, stents should be placed through the superior and inferior canaliculi and brought out of the common canaliculus. It must be considered that the sac should stay open without the stenting action of the tubes. Finally, the end of the tubes can be knotted and cut. The nose can be packed lightly. If there

The principles are similar to those of primary DCR. As far as the bone along the lateral nasal wall has already been removed, endoscopic revision DCR is much easier than the primary

If the sac is normal in size, the rate of success is high (89%)11, 12. If there is scarring and cicatrizaion of the sac, the success rate is lower because only a small amount of lacrimal

In severe stenosis and scarring of the lacrimal sac, the agger nasi mucosa can be used as a free graft to create functional mucosa surrounding the common canaliculus-sac junction.

If nasal packing is placed at the end of surgery, it is removed the following morning. Patients must irrigate their nose with saline at least twice a day. The patient must be visited

The silastic tubing is removed 1-12 months after surgery. According to our experience, we recommend removing the tube in about 4 weeks after surgery. Exposed tubing at the medial canthus is cut with scissors and the stent is withdrawn through the nose. In revision cases

During surgery sufficient opening from the lacrimal sac into the nose is made, but the final

Complications of endonasal DCR surgery can be divided into intraoperative and early or late postoperative. Early postoperative (up to one month) complications include hemorrhage, crusting, perirhinostomy granuloma, and transnasal synechiae; 1 - 6 months side effects of surgery include surgical failure from impacted tubes, rhinostomy scarring, granuloma, and synechiae. Most of these later complications occur between one and three

procedure. The important point in revision DCR is the size of the lacrimal sac.

lacrimal probe, its metallic part can be seen within the translucent sac wall.

is minimal risk of epistaxis, no packing is needed.

mucosa can be marsupialized.

**8. Postoperative care** 

**9. Complications** 

months after surgery13.

**7. Revision endoscopic dacryocystorhinostomy** 

one week later and intranasal debris must be removed then.

with scarring the stent can be left in the place for 6 months or even longer.

size of the healed surgical ostium is 1 to 2 mm in diameter on average.

Fig. 4. High endoscopic septoplasty. Ideal area of removal is indicated by a dashed line.

A 30-degree scope is used through the procedure to have adequate visualization around the frontal process of the maxilla. A DCR flap must be created considering the lacrimal sac in mind. The superior incision must be 5mm posterior and 10mm superior to the axilla. It is brought 10mm anterior to the middle turbinate to be able to marsupialize the lacrimal sac fully. The inferior incision would be at the insertion of the inferior turbinate.

An elevator is used to make a subperiosteal plane along the incisions towards the frontal process of the maxilla. The flap must be mobilized over the frontal process of the maxilla until the lacrimal bone is identified. The best place to identify the lacrimal bone is the region adjacent to the inferior horizontal incision just above the inferior turbinate. Superiorly, the flap is elevated on to the insertion of the middle turbinate and posteriorly, it is elevated past the lacrimal bone onto the uncinate process. When the flap is completely elevated, its inferior pedicle is cut off the superior aspect of the inferior turbinate and its insertion to the uncinate.

A round knife is used then to identify the junction of frontal process and lacrimal bone and to flake off the lacrimal bone. The posterioinferior aspect of the lacrimal sac and adjacent nasolacrimal duct would be exposed this way. Then, a punch is used to remove the frontal process of maxilla. Superiorly, the bone thickens and it would be difficult for the punch to grip the bone. Therefore, drilling with a DCR diamond bur may be required. Care must be taken to ensure that excessive pressure is not placed on the sac wall. When the lacrimal sac is opened, it will lie flat on the lateral nasal wall. It would be marsupialized. By removing the bone from the posterolateral region of the lacrimal sac, the mucosa of the agger nasi cell will be exposed. There is a pyramid-shaped bone between the anterior aspect of the agger nasi cell and the lacrimal sac which must be completely removed. The agger nasi mucosa is opened by a sickle knife.

Fig. 4. High endoscopic septoplasty. Ideal area of removal is indicated by a dashed line.

fully. The inferior incision would be at the insertion of the inferior turbinate.

uncinate.

opened by a sickle knife.

A 30-degree scope is used through the procedure to have adequate visualization around the frontal process of the maxilla. A DCR flap must be created considering the lacrimal sac in mind. The superior incision must be 5mm posterior and 10mm superior to the axilla. It is brought 10mm anterior to the middle turbinate to be able to marsupialize the lacrimal sac

An elevator is used to make a subperiosteal plane along the incisions towards the frontal process of the maxilla. The flap must be mobilized over the frontal process of the maxilla until the lacrimal bone is identified. The best place to identify the lacrimal bone is the region adjacent to the inferior horizontal incision just above the inferior turbinate. Superiorly, the flap is elevated on to the insertion of the middle turbinate and posteriorly, it is elevated past the lacrimal bone onto the uncinate process. When the flap is completely elevated, its inferior pedicle is cut off the superior aspect of the inferior turbinate and its insertion to the

A round knife is used then to identify the junction of frontal process and lacrimal bone and to flake off the lacrimal bone. The posterioinferior aspect of the lacrimal sac and adjacent nasolacrimal duct would be exposed this way. Then, a punch is used to remove the frontal process of maxilla. Superiorly, the bone thickens and it would be difficult for the punch to grip the bone. Therefore, drilling with a DCR diamond bur may be required. Care must be taken to ensure that excessive pressure is not placed on the sac wall. When the lacrimal sac is opened, it will lie flat on the lateral nasal wall. It would be marsupialized. By removing the bone from the posterolateral region of the lacrimal sac, the mucosa of the agger nasi cell will be exposed. There is a pyramid-shaped bone between the anterior aspect of the agger nasi cell and the lacrimal sac which must be completely removed. The agger nasi mucosa is The next step would be checking the lacrimal puncta and dilating them by a probe if required. A sinus endoscope would be helpful for lighting the region. By passing the lacrimal probe, its metallic part can be seen within the translucent sac wall.

Then the mucosal flap is positioned to approximate nasal mucosa to the lacrimal mucosa. The common canaliculus should be visible in the lateral sac wall. Then, stenting of the system would be done. If the lacrimal probes pass easily without any resistance in the canaliculus and the common canaliculus valve of Rosenmuller, lacrimal probes need not be placed. However, if there is tightness of common canaliculus, stents should be placed through the superior and inferior canaliculi and brought out of the common canaliculus. It must be considered that the sac should stay open without the stenting action of the tubes.

Finally, the end of the tubes can be knotted and cut. The nose can be packed lightly. If there is minimal risk of epistaxis, no packing is needed.
