Pilot study for comparative assessment of dual‐energy computed tomography and single‐photon emission computed tomography V/Q scanning for lung perfusion evaluation in infants

Abstract

Objective: To evaluate clinical applications of dual-energy computed tomography (DECT) in pediatric-specific lung diseases and compare ventilation and perfusion findings with those from single-photon emission computed tomography (SPECT-CT) V/Q. Methods: All patients at our institution who underwent exams using both techniques within a 3-month period were included in this study. Two readers independently described findings for DECT, and two other readers independently analyzed the SPECT-CT V/Q scan data. All findings were compared between readers and disagreements were reassessed and resolved by consensus. Inter-modality agreements are described throughout this study.Results: Eight patients were included for evaluation. The median age for DECT scanning was 3.5 months (IQR = 2). Five of these patients were scanned for both DECT and SPECT-CT V/Q studies the same day, and three had a time gap of 7, 65, and 94 days between studies. The most common indications were chronic lung disease (5/8; 63%) and pulmonary hypertension (6/8; 75%). DECT and SPECT-CT V/Q identified perfusion abnormalities in concordant lobes in most patients (7/8; 88%). In one case, atelectasis limited DECT perfusion assessment. Three patients ultimately underwent lobectomy with corresponding perfusion abnormalities identified by all reviewers on both DECT and SPECT-CT V/Q in all resected lobes. Conclusion:DECT is a feasible technique that could be considered as an alternative for SPECT-CT V/Q for lung perfusion evaluation in infants.

Calculating Relative Lung Perfusion Using Fluoroscopic Sequences and Image Analysis: The Fluoroscopic Flow Calculator

“…Notably, LPS is associated with a nontrivial radiation exposure (0.5-1.3 mSv) for children already at risk for radiation-associated complications due to serial catheterizations and imaging. [10][11][12][13] While CMR avoids radiation, it often requires anesthesia and can be time-consuming. Further, the accuracy of CMR estimates of Q p maldistribution can also be affected by turbulent flow at sites of discrete stenosis, or due to technical errors, such as incorrect planning of scan parameters or angles.…”

Dual-source computed tomography protocols for the pediatric chest — scan optimization techniques

“…Importantly, atelectatic lung might appear as non-perfused, and therefore the anatomical images must be viewed in concert [ 26 ]. When imaging lung that is denser, such as in atelectasis or in intrinsically dense lungs such as in neonates, older infants and those with chronic lung disease, one should use the “dense lung” tool [ 27 ]. This change results in increased maximal Hounsfield units analyzed, ultimately including perfused lung that would otherwise be missed (Fig.…”

“…These exams are usually ultra-high-pitch scans, particularly if the child is not sedated. However, dual-energy CT can be used to assess blood flow to the parenchyma, which might decrease the need for additional nuclear medicine ventilation–perfusion scan [ 27 ]. The most important post-processing tool is the pulmonary blood volume.…”

“…Dual-energy scanning has also been shown to have favorable comparison in dose to single-energy scanning [ 16 , 24 , 40 ]. There have been reports of slightly higher doses in children younger than 1 year when using dual-energy mode for chest imaging with a second-generation scanner [ 41 ], though the benefits of dual energy might outweigh the small increase in radiation dose when eliminating the need for dual-phase scans or additional tests such as a nuclear medicine perfusion study [ 27 ].…”

Dual-energy computed tomography to detect early pulmonary vascular changes in children with sickle cell disease: a pilot study

“…Based on the attenuation properties of iodine, DECT provides pulmonary blood volume maps and quantifies the iodine concentration in the parenchyma, thus allowing simultaneous analysis of the gray-scale vasculature and color-scale parenchymal perfusion ( 13 ). In infants with chronic lung diseases and/or PH, DECT exhibited a similar efficacy to ventilation/perfusion scintigraphy for lung perfusion assessment ( 14 ). Moreover, it had been demonstrated that DECT is a valuable tool for diagnosing PH, regardless of the underlying mechanism or the age of the patient ( 13 , 15 ).…”