Acquired Nasolacrimal Duct Obstruction:

Etiology & ManagmentNeda Ahmadi

PGY-411/18/10

Georgetown University Hospital

Case Presentation

Imaging

Outline

Anatomy• Puntal opening - ~0.3mm in diameter

• Canaliculus - Extends 2mm vertically

• Turns 90 degrees toward the medial canthus & travels through the orbicularis muscle (8mm)

• Inferior & superior canaliculi form a common canaliculus - 90% to 94% of individuals

• Common canaliculus and lacrimal sac - Between ant. & post limbs medial canthal ligament (MCL)

• Valve of Rosenmuller

• Lacrimal sac – 12-15 mmExtends 3-5mm superior to MCL

Chastain JB, Sindwani R. Anatomy of the orbit, lacrimal apparatus, and lateral nasal wall. Otolaryngol Clin North Am. 2006 Oct;39(5):855-64, v-vi.

Anatomy

• Lacrimal sac lies within the lacrimal fossa

• Avg. width of lacrimal fossa – 8mm

• Anterior lacrimal crest - Formed by frontal process

of maxilla

• Posterior lacrimal crest - Formed by lacrimal bone

Chastain JB, Sindwani R. Anatomy of the orbit, lacrimal apparatus, and lateral nasal wall. Otolaryngol Clin North Am. 2006 Oct;39(5):855-64, v-vi.

Intranasal Anatomy

• Frontal process of maxilla covers anterior half of sac

• Thin lacrimal bone covers posterior half.

• Almost always sac lies anterior to middle turbinate

• 0% and 20% of sac - Above the attachment of MT

• Sac extends on average 8.8mm superior to insertion of MT

Wormald PJ, et al. Intranasal anatomy of the nasolacrimal sac in endoscopic dacryocystorhinostomy. Otolaryngol Head Neck Surg. 2000 Sep;123(3):307-10.

• Retrospective study

• 38 subject w/ recurrent epiphora - CT dacryocystogram (DCG)

• Height of sac measured

Common Canaliculus Middle turbinate insertion

Conclusions

• No difference between measurements taken in relation to the long axis of the sac and those parallel to supraorbital ridge (P>0.05)

• A major portion of the sac was located above the MT

• The common canaliculus provides a valuable landmark for endoscopic surgeon bc a significant portion of sac lies above its insertion.

Wormald PJ, et al. Intranasal anatomy of the nasolacrimal sac in endoscopic dacryocystorhinostomy. Otolaryngol Head Neck Surg. 2000 Sep;123(3):307-10.

Intranasal anatomy

• NLD - ~4mm anterior to maxillary sinus ostium (MSO)

• NLD orifice - Roof of inferior meatus

• ~25mm from anterior nasal spine

• ~13.7 +/- 3.15mm from nasal floor

• ~14.3 +/- 2.05mm from anterior attachment of inferior turbinate

• NLD courses superiorly and anteriorly from the orifice toward the anterior attachment of MT

• Average NLD length - 22mm (18-24mm)

Intraosseous – 12mm

• R & L canals run parallel Slope posteriorly 15-25o

Tatlisumak E et al. Surgical anatomy of the nasolacrimal duct on the lateral nasal wall as revealed by serial dissections. Anat Sci Int. 2010 Mar;85(1):8-12.

Janssen AG, Diameter of the bony lacrimal canal: normal values and values related to nasolacrimal duct obstruction: assessment with CT. AJNR Am J Neuroradiol. 2001 May;22(5):845-50.

Maxillary Line• Curvilinear eminence along the lateral nasal wall

• Chastain et al. 2005– Objective: Describe the anatomic relations of maxillary line– Intranasally - Attachment of the uncinate process to the maxilla – Extranasally - Suture line between the lacrimal bone and the frontal

process of the maxilla within the lacrimal fossa– M point ~10.8 mm anterior to maxillary ostium– Axial line drawn through the M point –

Level of the superior margin of the MSO posteriorly & just inferior to the lacrimal sac-duct junction anteriorly

– M point within 3mm of lacrimal apparatus in all but 1 specimen– ~1/2 lacrimal sac - Anterior to this line

Chastain JB et al. The maxillary line: anatomic characterization and clinical utility of an important surgical landmark. Laryngoscope. 2005 Jun;115(6):990-2.

• Retrospective study; 314 patients (64% M: 36% F) w/o epiphora or pathologic conditions affecting NLD

• Axial maxillofacial CT (3-4mm)

• Results – Mean AP diameter 5.6 mm (0.4-10.9mm)

– Mean transverse 5.0mm (2.2-8.7mm) diameter

– AP diameter greater in M (5.8mm) vs F (5.3mm) (P<0.001)

– Transverse diameter greater in M (5.1mm) vs F (4.8mm) (P<0.005)

– Cross sectional area of bony NLD greater in M (23.6mm2) vs. F (20.6mm2) (P<0.001)

Shigeta K et al. Sex and age differences in the bony nasolacrimal canal: an anatomical study. Arch Ophthalmol. 2007 Dec;125(12):1677-81.

Age affected • Male

– Transverse diameter (P=0.002), – Cross sectional area (P=0.002) – Trend for AP diameter to increase with age

(P=0.04)

• Female– AP diameter (P<0.001)– Cross sectional area (P,0.001) – Trend for transverse diameter to increase with – age (P=0.02)

Overall• Female

– AP diameter ~0.6mm smaller– Transverse diameter ~0.3mm smaller– Cross sectional area ~13% smaller in F pts

Etiology

• 3% of all ophthalmology visits

• Congenital – Prevalence ~20%– Most common cause – Persistent membrane at valve of Hasner– Normally resolves spontaneously at 6-14 months of age

• Acquired– Incidence - 20.24 per 100,000 – Presenting symptoms

• Epiphora • Dacryocystitis

Lee-Wing MW, Clinicopathologic analysis of 166 patients with primary acquired nasolacrimal duct obstruction. Ophthalmology. 2001 Nov;108(11):2038-40.

Examination• Lacrimal pump function

– Lower punctum – Medial translation and inward rotation normally w/ blinking. – Not observed – Consider lacrimal pump failure

• Shirmer testing– Measures basal & stimulated – Differentiates primary hypersecretion from reflex hypersecretion– W/o anesthesia (Stimulated)

– Normal – 10-30mm at 5 min– <10mm at 5min indicates dry eye which may be associated with reflex

hypersecretion and epiphora

– W/ anesthesia (Basal) • Normal - >10mm at 5 min• Primary hypersecretion if whole strip wet

Examination

• Jones I