WS24.3 Evaluation of the performance of sonic nebuliser to target maxillary sinuses

Intranasal nebulisation seems to be the best therapeutic option for local antibiotic delivery, targeting infected sites beyond the nasal valve, especially for CF patients whose maxillary sinuses (MS) may be a source for bacterial inducing lung infections. In this study, we have evaluated the NL11SN sonic nebuliser (100 Hz) on MS ventilation and on aerosol deposition, in an in vitro model and in normal volunteers. Scintigraphy of 81mKr gas ventilation and of 99mTc-DTPA sonic aerosol deposition with NL11SN (DTF, France) was performed in 7 subjects. MS deposition was quantified using an image processing method. In vitro nebulisations were performed in a plastinated head model either with 99mTc-DTPA or with gentamicin. 99mTc-DTPA deposited in the MS was quantified by image processing method and gentamicin by a fluorescence polarization immunoassay. Ventilation 81mKr images show that the 100 Hz sound increases MS gas ventilation.99mTc-DTPA nebulised in volunteers was mainly deposited into nasal cavities (2/3 vs.1/3 in lungs) with 4.9±2.5% of total nasal deposition in the MS. In the plastinated head model, sonic mode of NL11SN increased the gentamicin deposition in MS by a factor 3 (P<0.05). The 99mTc-DTPA nebulised in the head model was deposited as 44.2±2.0% in the nasal cavities, with 4.6±2.6% into the MS (in term of total nasal deposition). The NL11SN sonic nebuliser can be used efficiently with antibiotics to target the nasal cavities including maxillary sinuses, a major site of bacterial infections. Compared to pulmonary deposition, the amount of sinus drug deposition per unit of tissue surface seems sufficient to induce a local therapeutic effect.