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.

Use of Technetium-99m-Labelled Sodium Diphosphate Decahydrate to Assess Right Ventricle Dysfunction in Patients with Pulmonary Embolism

The objective of this study was to identify the signs of the right ventricular dysfunction in patients with non-massive pulmonary artery thromboembolism (PE) using radionuclide gated blood pool SPECT (GBPS). The study included 55 patients: 40 with PE, and 15 - control group. Radionuclide studies included perfusion-ventilation scintigraphy and GBPS. GBPS results suggest that the signs of right ventricular dysfunction in PE are: the reduction in its stroke volume, as well as reduction in the peak filling and ejection rate. GBPS results allow distinguishing acute thromboembolism and chronic post-thromboembolic pulmonary hypertension.

Treatment of a Prolonged Air Leak with Radiotherapy: A Case Report

Pneumothorax is defined as air in the pleural space. Depending on the severity of the pneumothorax, treatment consists of oxygen therapy, simple aspiration, tube thoracostomy, and pleurodesis. Prolonged air leakage is observed in 25% of the patients who have undergone surgical procedures, such as thoracotomy, pleurectomy, and video-assisted thoracoscopy. The patient presented here is the third reported case successfully treated with radiotherapy. Ventilation scintigraphy was used to localise the air leak, and localised radiotherapy was performed at the targeted location. After radiotherapy, the air leak ceased and at the 3-month followup, the pneumothorax had not recurred. Radiotherapy can be a treatment modality for patients with prolonged air leak, who are not candidates for surgery.