The gold standard for diagnosis is irrigation of saline through the tear drainage system via a lacrimal cannula through the punctum and canaliculi. Passage of saline through the system into the nasal cavity confirms that the system is patent. Reflux from the opposing punctum indicates an obstruction.
Diagnosis of acute or chronic infection of the tear drainage system confirms a diagnosis of PANDO. This is diagnosed by visualizing an enlarged and inflamed lacrimal sac or discharge coming from the puncta when pressure is applied on the lacrimal sac.
Maxillofacial CT scan is considered for certain cases—such as young adults, those with a history of maxillofacial trauma or malignancy, and those with severe chronic rhinosinusitis—to determine if concurrent functional sinus surgery may be appropriate.
Nasal endoscopy may reveal problems in the nasal cavity requiring surgery, such as a deviated nasal septum, chronic rhinosinusitis, concha bullosa (air pocket in the middle concha), tumor, or scarring.
Another test for PANDO is to trace the movement of dye through the lacrimal drainage system in one of two ways: 1) dacryocystography, where dye is injected in the tear duct and traced with X-ray and/or CT scan, or 2) dacryoscintigraphy, where a radiotracer eye drop is placed in the conjunctival cul-de-sac and its movement is recorded over time through a series of gamma camera images.
DCR surgery may be performed traditionally via a small skin incision by the inner lower eyelid area that heals very well, or via an intranasal endoscopic approach. These techniques yield equivalent success rates, and either technique may be appropriate based on surgeon experience and potential need for other intranasal procedures (such as septoplasty or sinus surgery).
Dacryocystorhinostomy (DCR) surgery is the primary treatment for PANDO. Surgeons direct the lacrimal sac to drain into the nasal cavity in a slightly different location, bypassing the obstruction. DCR resolves tearing and infection in more than 90% of patients.
All patients diagnosed with PANDO should be referred to an oculoplastic surgeon with expertise in lacrimal surgery. Ophthalmologists are also encouraged to refer PANDO suspects who require advanced testing for an accurate diagnosis.
Daniel R. Lefebvre, MD, FACS
Assistant Professor of Ophthalmology, Harvard Medical School
Ophthalmic Plastic Surgery Service, Mass. Eye and Ear