Performance and Feasibility of Therapeutic Vibrating Mesh Nebulizer for Ventilation Lung Scan

This study aimed to evaluate the performance of a therapeutic vibrating mesh-type nebulizer for the pulmonary delivery of radioaerosols for lung scintigraphy in healthy subjects. Six healthy subjects (mean age of 28.7 ± 6.2 y) inhaled 2 mL of Tc-99m diethylenetriaminepentaacetic acid (DTPA) and normal saline solution (20 mCi) via the therapeutic vibrating mesh nebulizer (DK010, DELBio, Taipei, Taiwan). The nebulizer’s mass median aerodynamic diameter (MMAD) is between 2.3 μm and 5.0 μm (3.47 ± 0.37 μm) and the nebulization rate is greater than 0.2 ml/min. Scintigraphy was performed to count radioaerosols in the regions of interest to determine the total and regional lung deposition and extrathoracic airway deposition of aerosols, penetration of aerosols, and radioactivity count balance. The total lung deposition of aerosols was 21.2 ± 5.2% (% ex-valve dose), 27.4 ± 8.0% (% ex-device dose) and 13.8 ± 4.1% (% initial dose) in nebulizer. The extrathoracic airway deposition was 4.8 ± 1.1%. The radioactivity count balance was 5.4 ± 3.0%. The ratio of outer vs inner lung deposition (O/I ratio, or penetration index) was 1.89 ± 0.55. The delivery efficiency and the penetration of aerosols to the peripheral lung achieved by the DELBio DK010 vibrating mesh-type nebulizer are similar to the commercialized jet-type nebulizers dedicated for radioaerosol lung scintigraphy nebulizer. The therapeutic vibrating mesh-type nebulizer (DELBio DK010) is feasible for radionuclide lung ventilation scintigraphy.

Flow volume curve: A diagnostic tool in extrathoracic airway obstruction

The flow-volume loop (F/V-loop) is a presentation of inhalation and exhalation of air stream volume during inspiration and expiration. It demonstrates the obstructive, restrictive and mixed pattern lung pathology. Flow-volume loop has been extensively used for evaluating the severity, progression and resolution of various causes of upper-airway conditions. doi: https://doi.org/10.12669/pjms.36.4.2283 How to cite this:Al-Khlaiwi T. Flow volume curve: A diagnostic tool in extrathoracic airway obstruction. Pak J Med Sci. 2020;36(4):---------. doi: https://doi.org/10.12669/pjms.36.4.2283 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.