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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Available from: Richard J Harvey, Oct 04, 2015
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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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    PLoS ONE 04/2013; 8(4):e61694. DOI:10.1371/journal.pone.0061694 · 3.23 Impact Factor
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    ABSTRACT: Our group has previously described a novel method of objectively quantifying the temporospatial distribution of sinonasal irrigation in a nonanesthetized patient. The purpose of this study is to refine this technique to provide an accurate method of determining concentration of dose delivery as well. An endoscope at a fixed position within 2 dissected cadaveric heads was used to image 4 subsites under blue light. Each site was dosed with 3 mL of successively increasing concentrations of fluorescein-labeled saline. In vitro images of the labeled saline were also captured over a range of depths. Images were exported into a graphics editing program that was used to calculate luminosity at 3 regions per subsite. The relationship between luminosity and fluorescein concentration was calculated using a Pearson product-moment correlation coefficient. Significance was determined using a 2-tailed Student t test. Luminosity of the irrigation delivered to the maxillary sinus, lamina papyracea, ethmoid roof, and frontal sinus positively correlated with fluorescein concentration over a range of 0.1 to 0.01 mg/mL (n = 6; r = 0.95, p < 0.001; r = 0.94, p < 0.001; r = 0.92, p < 0.001; and r = 0.94, p < 0.001; respectively). There was no significant difference between luminosities of a 0.01 mg/mL irrigation layer subtending a range of depths up to 6.6 mm. The described method is capable of determining the concentration of fluorescein delivery to a mucosal surface via objective luminosity quantification. Our data suggest that this method will remain accurate regardless of the potential for heterogeneous pooling of irrigation. This method may be used to optimize delivery strategies of a variety of topical sinonasal therapies.
    International Forum of Allergy and Rhinology 07/2012; 2(4):316-20. DOI:10.1002/alr.21034 · 2.37 Impact Factor
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    International Forum of Allergy and Rhinology 09/2013; 3(9). DOI:10.1002/alr.21172 · 2.37 Impact Factor
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