Estimation of regional lung function in interstitial pulmonary disease using Tc-99m-Technegas and Tc-99m-macroaggregated albumin single-photon emission tomography
Y. Sasaki et al., Estimation of regional lung function in interstitial pulmonary disease using Tc-99m-Technegas and Tc-99m-macroaggregated albumin single-photon emission tomography, EUR J NUCL, 25(12), 1998, pp. 1623-1629
Citations number
19
Categorie Soggetti
Radiology ,Nuclear Medicine & Imaging","Medical Research Diagnosis & Treatment
For quantitative evaluation of the regional lung function in patients with
interstitial pulmonary disease (IP) in the sitting position, Tc-99m-Techneg
as and Tc-99m-macroaggregated albumin (MAA) single-photon emission tomograp
hy (SPET) studies were performed in 12 healthy controls (HC) and 42 IP pati
ents. Four transverse images were prepared from the data obtained and desig
nated as slices no. 1-4 from the top downward. Regions of interest (ROIs) w
ere determined in the anterior and posterior parts of the lung in each slic
e, and the ratio of the count per voxel in the ROIs to the count in the ent
ire lung was calculated as the regional Technegas index (T). The regional p
erfusion index (Q) was calculated by a similar procedure using the data of
Tc-99m-MAA SPET. The ratios between T and Q (T/Q) in the anterior and poste
rior regions of the lung, and the ratios of T and Q between the anterior an
d posterior regions of the lung (Tp/Ta and Qp/Qa) were examined. In the HC
group, T/Q decreased but Tp/Ta and Qp/Qa increased from the upper re the lo
wer lung fields. When IP patients were classified into (I) those in whom T/
Q decreased from the upper to the lower lung fields, (II) those in whom it
was similar in all slices, (III) those in whom it increased from slice 3 to
slice 4, and (IV) those in whom it increased from slice 2 to slices 3 and
4, this classification was more closely correlated with %VC than with %DLCO
or PaO2. When the patients were classified according to Tp/Ta and Qp/Qa in
to (A) those in whom the values were greater in the lower than the upper lu
ng field, (B) those in whom the values were similar in all slices, and (C)
those in whom the values were smaller in lower than in upper lung fields, c
ategories B and C were observed frequently even in patients whose %VC was i
n the normal range. This method is considered to be an effective means to e
valuate the progression and pathology of IP and to detect early impairment
of lung function.