H.10 Drainage of Surgically Created Artificial Tear Ducts
The lacrimal drainage system, commonly known as the “tear duct” removes tears from the eye. It consists of the puncta, canaliculi, lacrimal sac, and nasolacrimal duct.
Patients who develop obstruction of the tear ducts experience severe, bothersome tearing and infection. Obstruction may develop due to normal aging changes, infection, trauma, tumor, or on a congenital basis. A significant subset of lacrimal drainage problems are due to obstruction of the canaliculi which usually cannot be surgically reconstructed. Such patients require a conjunctivodacryocystorhinostomy (CDCR). This procedure creates an artificial tear duct by drilling through the bone of the lacrimal fossa and placing a Pyrex tube that directly connects the medial canthus to the nasal cavity, essentially bypassing the malfunctioning lacrimal drainage system permitting tears to drain into the nose. This device, commonly referred to as a Jones tube, has undergone numerous modifications due to significant problems with the implantation of a relatively large foreign body in this sensitive area (i.e. Putterman-Gladstone, Callahan-Cox, Straiko modified Jones tube, LEITR frosted Jones tube, Medpor-coated Jones tube, Stop-Loss Jones tube, angled Jones tubes, incorporation of suture holes and/or double flanged tubes in the above designs). Each design has its own pros and cons, but all options currently have functional concerns.
Irrespective of the design, all tubes are plagued by problems of dislocation and extrusion.
In one study, Jones tube extrusion occurred 2-6 times in around 25% of patients. In the same study, tube malposition occurred in roughly 25% of patients as well. Dislocation and extrusion usually necessitate a repeat surgical procedure under general anesthesia incurring significant additional cost and potential surgical morbidity.
A problem that no design modification has been able to address is reflux of air and secretions from the nasal passage into the eye. This is because, unlike the natural nasolacrimal system which is complete with a series of valves to prevent reflux, the Pyrex tubes are essentially a “two-way street”. This is especially problematic for patients who use CPAP (continuous positive airway pressure) for obstructive sleep apnea or supplemental oxygen for other pulmonary conditions. Such patients are poor candidates for Jones tubes due to the very bothersome air and mucus that reflux onto the ocular surface from the nasal cavity.
Our goal is to design a novel tear duct tube with the following properties:
– Stable, secure placement and fixation to minimize dislocation and extrusion
– Convenient removal and reinsertion in clinic for cleaning
– Minimizing reflux of air and secretions from the nasal cavity
– Accommodation of CPAP therapy.
- Lim C, Martin P, Benger R, Kourt G, Ghabrial R. Lacrimal canalicular bypass surgery with the Lester Jones tube. Am J Ophthalmol. 2004 Jan;137(1):101-8. doi: 10.1016/j.ajo.2003.08.002. PMID: 14700651.
- Jones LT. The cure of epiphora due to canalicular disorders, trauma, sand surgical failures on the lacrimal passages. Trans Amer Acad Ophthal Otolaryngol. 1962;66:506-524.
- Paulsen F. Anatomy and physiology of the nasolacrimal ducts. In: Atlas of Lacrimal Surgery. Springer Berlin Heidelberg; 2007:1-13.
- Biology/Pre-Health Experience
- Material Science