Abstract
Purpose :
With canalicular sacrifice or stenosis, Jones tubes offer the only means of restoring lacrial drainage. Despite their efficacy, they confer significant disadvantages. As foreign bodies, they are prone to migration, blockage, and infection. However, attempts to create neo-canaliculi with mucosal tissue invariably end in re-stenosis, while canalicular transplantation can compromise contralateral drainage. We present an alternate concept for canalicular reconstruction using the superficial temporal artery (STA).
Methods :
Cadaveric heads were obtained and proximal STA isolated and harvested. DCR incisions were then created, and the anterolateral sac mucosa identified. A paracentesis blade was used separate anterior and posterior lid lamella in the desired location for a neo-punctum (Figure 1A). A medium Monoka (FCI Ophthalmics, Pembroke, MA) was modified by removing the internal flange and STA advanced over the attached probe. An 8-0 ligature was placed to anchor the distal STA to the underlying stent (Figure 1B). An 18-gauge spinal needle was then used to tunnel in the sub-orbicularis plane, emerging through the lid margin division (Figure 1C). The probe was introduced via the spinal needle (Figure 1D, 2A/B). An sac aperture was created and the probe passed and retrieved beneath the inferior turbinate (Figure 2C). The external Monoka flanges were anchored to the lid margin using 8-0 polyglactin (Figure 2D). The ligature was removed and the STA trimmed and anastomosed to the sac.
Results :
The STA bypass graft concept for nasolacrimal drainage was successfully executed in a cadaveric model.
Conclusions :
The STA is used for bypass grafts in ischemic cerebrovascular disease, and techniques for cannulation and suturing are established. As needed, vessel suitability can be assessed pre-operatively using CT angiography. The indwelling stent would keep the lumen patent during healing. Antibiotic/steroid drops and serum tears (to provide endothelial growth factors) could be applied. With arteries lacking vasa vasorum, diffusion provides adequate oxygen and nutrients, and transplanted vessels could likely survive and undergo metaplasia. Unlike mucosa, the STA has a muscular media to resist collapse and re-stenosis, increasing the likelihood of long term function. Unlike a Jones tube, the STA graft would preserve the lacrimal pump mechanism, resulting in active siphoning of tears.
This is a 2020 ARVO Annual Meeting abstract.