Article Figures & Data
Figures
- FIGURE 1.
Annotated front view of Technegas generator. Chamber drawer is in closed position, and shield is closed down over administration set port. Not all models are fitted with easy-breather option. PAS = patient-administration set. (Courtesy of Cyclomedica.)
- FIGURE 2.
Annotated rear view of Technegas generator demonstrating connection of argon to system. (Courtesy of Cyclomedica.)
- FIGURE 3.
Use of gloves and good dexterity are required to place crucible between contacts, making good connection with fracturing crucible. For photography purposes, lead acrylic shield has been removed. (Courtesy of Cyclomedica.)
- FIGURE 4.
(Top) Excess 99mTc added to crucible well will be blown off during simmer and wasted. (Reprinted with permission of 18). (Bottom) Built-in simmer oven for crucibles in chamber to allow multiple simmer cycles for low-concentration 99mTc. (Courtesy of Cyclomedica.)
- FIGURE 5.
(Top left) Disposable administration set with multiple mouthpiece options to suit patient. (Bottom left) Administration set delivers Technegas to patient (red line) and returns patient breath through filter (yellow line) using 1-way valve to prevent communication between the 2 airflows (cross) and filtering both radioactive and biologic content of patient expiration to produce uncontaminated output into room air (green line). (Right) Entire administration set is disposed of in its original plastic bag. (Courtesy of Cyclomedica.)
- FIGURE 6.
State-of-art contemporary SPECT/CT imaging of lung ventilation (top row) and perfusion (bottom row) in 3 orthogonal planes. SPECT/CT images demonstrate segmental perfusion defect (arrow in D and F) in left lower lobe. This appears mismatched when compared with corresponding ventilation images. Notch at apex of left lung seen in sagittal views (C and F) is matched on ventilation and perfusion and therefore is unlikely to be due to embolus.
- FIGURE 7.
Technegas production cycle, beginning with checking and loading chamber. (Inset courtesy of Cyclomedica.)
Tables
1 Performing ventilation upright produces distribution different from that when performed supine. 99mTc-macroaggregated albumin should be administered for perfusion in same position as that in which ventilation was performed. 2 Gloves and gown should be worn when performing the ventilation stage as this is biggest risk for contamination. This stage also requires face masks to be worn for coronavirus disease 2019 compliance. 3 For days on which eluate has high specific concentration, eluate should be diluted so that no more than 900 MBq are contained in 0.15-mL volume. 4 When used as per instruction, Technegas produces minimal contamination risk to staff and no risk of cross contamination between patients, a very important advantage with coronavirus disease 2019 (16). 5 Any unused crucibles in simmer oven at end of day can be cleansed with ethanol the next day and reloaded for simmer. 6 Since Technegas does not clear through kidneys, compared with 99mTc-diethylenetriaminepentaacetic acid aerosol studies, radiation dose to kidneys, bladder, and fetus is lower (17).
