Temporospatial quantification of fluorescein-labeled sinonasal irrigation delivery

Massachusetts Eye and Ear Infirmary, Harvard Medical School, Boston, MA, USA.
International Forum of Allergy and Rhinology (Impact Factor: 2.37). 09/2011; 1(5):361-5. DOI: 10.1002/alr.20041
Source: PubMed


Treatment of sinonasal disease is predicated on the delivery and retention of the agent at the desired location. Despite multiple distribution studies, there remains a need for a method capable quantifying not only the site and amount of agent deposition but the rate of clearance as well.
Five patients underwent endoscopic image capture of 3 subsites over 15 minutes following fluorescein-dyed irrigation using a squeeze bottle, nasal saline spray, or nasal gel spray. Area and intensity staining were quantified using a graphics editing program. Total intensity scores were compared using a Student t test.
The squeeze bottle was the only method demonstrating delivery to the oropharynx (37 ± 22 mm(2) ). The nasal gel resulted in the greatest coverage of the middle turbinate region (10 ± 15 mm(2) ) while the nasal saline spray (75 ± 31 mm(2) ) resulted in the greatest inferior turbinate coverage. No significant differences in clearance rates were found between delivery methods at any subsite.
This method is capable of quantifying both the area and intensity of fluorescein deposition using a variety of delivery methods. While small variations in subsite coverage were noted, all methods resulted in significant internal valve deposition. Despite differences in delivery volume and viscosity, all methods resulted in similar rates of fluorescein clearance.

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    • "While this delivery route has been successfully demonstrated in animal models [14], its clinical utility is less clear. The relative paucity of human olfactory mucosa coupled with its location in a region with little access for topical agents [15] suggests that these rodent studies may vastly overstate the clinical potential of transnasal CNS delivery through an intact skull base. In a critical analysis of 100 papers examining this pathway only 2 approached satisfactory evidence for utility of the transnasal route [16]. "
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