What is the recommended treatment for symptomatic nasolacrimal duct obstruction using DCR (Dacryocystorhinostomy)?

Dacryocystorhinostomy (DCR) for Symptomatic Nasolacrimal Duct Obstruction

For symptomatic nasolacrimal duct obstruction, external DCR remains the gold standard surgical treatment, with success rates of 89-93%, though endoscopic endonasal DCR (EN-DCR) now achieves comparable outcomes when performed with mucosal flap preservation and is preferred when avoiding external scarring is important. 1, 2, 3

Surgical Approach Selection

External DCR (Gold Standard)

• External DCR is the established gold standard with objective success rates of 92.9% and subjective success rates of 89.3% at 6 months. 4
• The modified technique with anterior mucosal flap anastomosis only (excising posterior flaps) reduces operative time to approximately 36 minutes while maintaining high success rates. 4
• Key advantage: Direct visualization and reliable mucosal flap creation. 5, 4
• Main disadvantage: External scar on the lateral nasal wall and potential damage to the medial palpebral pump mechanism. 1, 3

Endoscopic Endonasal DCR (EN-DCR)

• EN-DCR with preservation of both lacrimal and nasal mucosa achieves 98% success rates at 3 months, comparable to external DCR. 2
• Success depends critically on creating posteriorly hinged lacrimal sac and nasal mucosal flaps to ensure epithelialized surgical site. 2, 3
• Distinct advantages include no external scar and preservation of the lacrimal pump mechanism. 3
• Manual osteotomy of the frontal process of maxilla and lacrimal bone removal can be performed without power drills. 2

Transcanalicular Laser-Assisted DCR

• This approach should be reserved as a second-step procedure after failed recanalization but before external DCR, with functional success of only 77%. 1
• Surgical success rate of 97% for completing the procedure, but 23% functional failure rate with persistent epiphora. 1
• Complications include thermal canalicular injury, canalicular infection, and silicon tube prolapse. 1

Critical Technical Considerations

Mucosal Flap Management

• Preservation and anastomosis of mucosal flaps is essential—creating raw surfaces leads to granulation tissue and reocclusion. 5, 2
• The DCR-anastomosis (DCR-A) technique with end-to-side anastomosis under microscopic visualization and circumferential suturing eliminates raw surfaces entirely. 5
• DCR-A requires no additional postoperative therapy compared to conventional DCR. 5

Silicone Stent Intubation

• Current evidence indicates silicone stents provide limited benefit in primary cases, though they are commonly used. 3
• Bicanalicular silicon intubation is standard with transcanalicular approaches. 1
• Stent-related complications include prolapse (10% in one series). 1

Adjunctive Measures

• Mitomycin C application improves success rates, particularly in revision EN-DCR cases. 3
• Concomitant septoplasty and anterior middle turbinectomy may be required in both primary and revision cases to achieve optimal access and outcomes. 3

Indications Beyond Primary Acquired NLDO

EN-DCR indications now extend to: 3

• Revision DCR procedures
• Acute lacrimal sac abscesses
• Nasolacrimal duct obstruction following chemotherapy or radiation
• Common canalicular obstructions

Preoperative Diagnosis Confirmation

• Diagnosis requires both symptomatic epiphora/dacryocystitis AND objective findings. 2
• Blocked irrigation of the nasolacrimal system confirms obstruction. 2
• Dacryocystography can provide additional anatomic detail when needed. 2

Follow-Up Protocol

• Standard evaluation at 1 week, 1 month, and 3 months postoperatively. 2
• Assessment includes subjective symptom relief, lacrimal irrigation patency, and endoscopic visualization of the ostium at 3 months. 2
• Success is defined by both patent irrigation AND resolution of epiphora. 2, 4

Common Pitfalls to Avoid

• Failing to create proper mucosal flaps leads to uncontrolled epithelialization and higher failure rates. 2, 3
• Inadequate osteotomy size restricts mucosal flap positioning. 2
• In EN-DCR, inability to position instruments at the anteroinferior rim of the middle turbinate occurs in approximately 3% of cases using superior canalicular approach. 1
• Intraoperative hemorrhage (5.3%) and nasal mucosa laceration (7.1%) are manageable complications. 4