[Correction of Partial Volume Effect Using CT Images in Brain F-FDG PET].

Purpose: We performed partial volume effect correction of PET images using F-FDG-PET and CT images taken consecutively, compared it with correction using MRI images, and investigated the usefulness of correction using CT images.

Methods: A total of 9 clinically normal subjects were included in the study, and the CT and MRI images of each subject were segmented and normalized. PET images were coregistered to each morphological image and then normalized.

Diagnostic Performance of I-FPCIT SPECT Specific Binding Ratio in Progressive Supranuclear Palsy: Use of Core Clinical Features and MRI for Comparison.

Progressive supranuclear palsy (PSP) is listed as a core clinical feature in the Movement Disorder Society 2017 criteria, along with ocular motor dysfunction, postural instability, akinesia, and cognitive dysfunction. Imaging evidence shows predominant mid-brain atrophy and postsynaptic striatal dopaminergic degeneration as two supportive features. The purpose of this study was to investigate the diagnostic performance of I- ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) nortropane (I-FP-CIT) SPECT by comparing it with evaluation of core clinical features and MRI in the diagnosis of PSP.

A diagnostic strategy for Lewy body disease using DAT-SPECT, MIBG and Combined index.

Purpose: The functional imaging methods widely used for the diagnosis of Lewy body disease (LBD) are I-N-ω-fluoropropyl-2β-carbomethoxy-3β-(4-iodophenyl) nortropan (FP-CIT) with dopamine transporter single photon emission computed tomography (DAT-SPECT) and I-iodobenzylguanidine (MIBG) myocardial scintigraphy. The aim of this study was to determine whether DAT-SPECT or I-MIBG myocardial scintigraphy should be examined first and to evaluate whether the combined use of DAT-SPECT and MIBG myocardial scintigraphy is superior to using either modality alone for diagnosing suspected LBD.

Methods: In this retrospective study, a total of 117 patients suspected of having LBD underwent DAT-SPECT imaging followed by MIBG myocardial scintigraphy.

Clinical usefulness of quantification of myocardial blood flow and flow reserve using CZT-SPECT for detecting coronary artery disease in patients with normal stress perfusion imaging.

Background: Relative myocardial perfusion imaging can misdiagnose "balanced" ischemia caused by coronary artery disease (CAD). We assessed the feasibility of myocardial blood flow (MBF) and myocardial perfusion reserve (MPR) using dynamic single-photon emission computed tomography (SPECT) with a cadmium-zinc-telluride (CZT) camera for estimating underlying CAD in patients with normal stress myocardial perfusion SPECT (MPS).

Methods: 125 patients with normal stress MPS (summed stress score ≤3) were enrolled.

Tc-99m PMT scintigraphy in the diagnosis of pediatric biliary atresia.

Purpose: Hepatobiliary scintigraphy plays an important role in the differentiation of biliary atresia (BA) and non-BA. The usefulness of Tc-iminodiacetic acid (IDA) derivatives in BA diagnosis is reported in several papers. In contrast, there are no comprehensive data on differentiating BA from non-BA using Tc-N-pyridoxyl-5-methyl-tryptophan (PMT).

Quantification of myocardial perfusion reserve using dynamic SPECT images of patients with chronic kidney disease.

Background: Chronic kidney disease (CKD) is an independent risk factor for cardiovascular disorders. The aim of this study was to examine whether the quantitatively measured myocardial blood flow (MBF) or myocardial perfusion reserve (MPR), calculated by dynamic single photon emission computed tomography (SPECT) analysis using a cardiac cadmium zinc telluride (CZT) gamma camera, was related to renal dysfunction in patients with normal myocardial perfusion imaging (MPI) findings.

Methods: The study population consisted of 46 patients with CKD and 46 individuals without CKD (controls).

Diagnosis of dementia with Lewy bodies: can I-IMP and I-MIBG scintigraphy yield new core features?

Objective: Since the clinical symptoms of different types of dementia frequently overlap, especially in the earlier stages at onset, it is difficult to distinguish dementia with Lewy bodies (DLB) from other neurodegenerative dementias based on their clinical manifestations alone. Nuclear medicine imaging has been reported as a high-value index for the objective evaluation and diagnosis of DLB. The aim of this study was to evaluate whether nuclear medicine imaging findings may yield core features to be added to the diagnosis of DLB.

I-MIBG myocardial scintigraphy for the evaluation of Lewy body disease: are delayed images essential? Is visual assessment useful?

Objective:: We performed I-meta-iodobenzylguanidine (I-MIBG) myocardial scintigraphy for the diagnosis of Lewy body disease (LBD) and assessed whether the early heart-to-mediastinum (H/M) ratio was diagnostic and whether visual image analysis was useful.

Methods:: Our study included 453 patients with clinically suspected LBD who had undergone I-MIBG myocardial scintigraphy. We evaluated semi-quantitative values (early and delayed H/M ratio, washout rate) and performed visual image analysis.

Reliability and advantages of using non-uniform Chang's attenuation correction method using a CT-based attenuation coefficient map in (99m)Tc-GSA SPECT/CT hepatic imaging.

Background: Generally, attenuation correction is made by incorporating a linear attenuation coefficient, which is based on the attenuation coefficient map (mu-map) created from a computed tomography scan, into the ordered subsets-expectation maximization reconstruction method in non-uniform domains. A non-uniform Chang's attenuation correction method that uses the mu-map created from a computed tomography image that was made after reconstruction has been performed is currently available. The purpose of this study was to determine the usefulness of the non-uniform Chang's attenuation correction method in (99m)Tc-galactosyl human serum albumin diethylenetriamine pentaacetic acid single photon emission computed tomography/computed tomography imaging.

Usefulness of the Chang attenuation correction method with use of a CT-based μ map by FBP reconstruction in (201)Tl SPECT-MPI.

Objective: Attenuation correction (AC) on nuclear images of non-uniform domains is generally performed by a change of the computed tomography (CT) values to μ values, which are then inserted as components into the detection probability of iterative reconstruction techniques (OS-EM Iterative AC). We established an AC technique which uses a CT μ map based on the Chang AC. Our purpose in this study was to confirm the appropriateness of the Chang AC with the OS-EM and the FBP method (OS-EM Chang AC and FBP Chang AC) by evaluating the results obtained in a phantom and clinical study for (201)Tl single-photon emission-computed tomography-myocardial perfusion imaging (SPECT-MPI).

Prediction of left main or 3-vessel disease using myocardial perfusion reserve on dynamic thallium-201 single-photon emission computed tomography with a semiconductor gamma camera.

Background: Myocardial perfusion imaging (MPI) may fail to detect balanced ischemia. We evaluated myocardial perfusion reserve (MPR) using Tl dynamic single-photon emission computed tomography (SPECT) and a novel cadmium zinc telluride (CZT) camera for predicting 3-vessel or left main coronary artery disease (CAD). METHODS AND RESULTS: A total of 55 consecutive patients with suspected CAD underwent SPECT-MPI and coronary angiography.

Quantitative index calculated by (99m)Tc-GSA scintigraphy.

(99m)Tc-galactosyl human serum albumin (GSA) scintigraphy is useful to evaluate hepatic function and hepatic functional reserve. A reliable SPECT and CT integrated system is now commercially available. Using this system, we can obtain (99m)Tc-GSA SPECT/CT fused imaging with a small registration error.

Assessment of hepatic functional regeneration after hepatectomy using (99m)Tc-GSA SPECT/CT fused imaging.

Background: The liver itself regenerates after hepatectomy but little is known about how much hepatic function recovers during the regeneration. The liver uptake value (LUV), calculated from Tc-99m-labeled galactosyl-human-serum-albumin ((99m)Tc-GSA) SPECT/CT fused images, is reliable and useful for evaluating hepatic function. In this study, we evaluated the clinical usefulness of LUV for estimating hepatic functional regeneration after hepatectomy.

Diagnosis of dementia with Lewy bodies: diagnostic performance of combined ¹²³I-IMP brain perfusion SPECT and ¹²³I-MIBG myocardial scintigraphy.

Objective: We assessed the value of combining (123)I-IMP brain perfusion SPECT and (123)I-MIBG myocardial scintigraphy for the discrimination of dementia with Lewy bodies (DLB) from other types of dementia.

Methods: We subjected 252 consecutive patients with clinically suspected DLB to both (123)I-IMP brain perfusion SPECT and (123)I-MIBG myocardial scintigraphy. Patients with Parkinson's disease were included.

[Evaluation of the detectability of vascular stenosis using non-contrast magnetic resonance angiography with various electrocardiographically-gated three-dimensional fast spin echo sequences].

Various three-dimensional fast spin echo (3D-FSE) sequences are used for non-contrast magnetic resonance angiography (MRA). Differences in the ability to detect vascular stenosis using these sequences, however, have not yet been evaluated. The purpose of this study is to evaluate the usefulness of each sequence for the detection of vascular stenosis by using a vascular phantom.

A quantitative index measured on ⁹⁹mTc GSA SPECT/CT 3D fused images to evaluate severe fibrosis in patients with chronic liver disease.

Purpose: We compared quantitative indices estimated by use of technetium-(99m) galactosyl human serum albumin ((99m)Tc-GSA) single-photon emission computed tomography (SPECT)/computed tomography (CT) fused imaging and hepatic fibrosis in patients with chronic liver disease.

Materials And Methods: On the basis of pathological findings we divided 161 patients into non-severe and severe fibrosis groups (n = 81 and n = 80, respectively). We measured 2 indices by (99m)Tc-GSA SPECT/CT fused imaging: liver uptake value (LUV) = [radioactivity (whole liver)/radioactivity (injected)] × 100/body surface area, and functional liver index (FLI) = [radioactivity (hepatocytes)/radioactivity (injected)] × 100/liver volume.

FDG-PET/CT-based gross tumor volume contouring for radiation therapy planning: an experimental phantom study.

As there is continuing controversy over the role of F-18-fluorodeoxyglucose (FDG)-positron emission tomography (PET)/CT-fused imaging in radiation therapy (RT) planning, we performed a phantom study to assess the feasibility of FDG-PET/CT-based gross tumor volume (GTV) contouring. The phantom set, consisting of an elliptical bowl and 6 spheres measuring from 10-37 mm in diameter, were filled with FDG to obtain 3 source-to-background ratios (SBRs) of 4, 8, and 16. The ratio to maximum intensity at 5% intervals was applied as the threshold for contouring.

Improvement of the (99m)Tc-ECD brain uptake ratio (BUR) method for measurement of cerebral blood flow.

Objective: The brain uptake ratio (BUR) method for the (99m)Tc-ECD SPECT, a non-invasive measurement method of rCBF, has been used in clinical practice in Japan, because it is simple to use. However, the accuracy of this method is limited, as it has problems in the determination of input function and the regression equation. The purpose of this study is to improve the BUR method by reconstructing the determination process of the input function and regression equation based on measurement of the rCBF by H (2) (15) O PET.

Fused 99m-Tc-GSA SPECT/CT imaging for the preoperative evaluation of postoperative liver function: can the liver uptake index predict postoperative hepatic functional reserve?

Purpose: To evaluate the role of hepatic asialoglycoprotein receptor analysis in the preoperative estimation of postoperative hepatic functional reserve.

Methods: We obtained technetium-99m-diethylenetriaminepentaacetic acid-galactosyl human serum albumin (99mTc-GSA) SPECT/CT fusion images in 256 patients with liver disease scheduled for hepatic resection. The liver uptake value corrected for body surface area [LUV(BSA)] and liver uptake ratio (LUR) of the remnant were preoperatively estimated based on the fused images.

Optimal setting of automatic exposure control based on image noise and contrast on iodine-enhanced CT.

Rationale And Objectives: The aim of this study was to investigate variations in image noise and contrast using automatic exposure control (AEC) and different tube voltages on nonenhanced and iodine-enhanced hepatic computed tomography.

Materials And Methods: Nonenhanced and iodine-enhanced simulated liver phantoms and AEC were used. Tube current was automatically adjusted with the noise index.

[Quantitative evaluation of calcium (content) in the coronary artery using hybrid iterative reconstruction (iDose) algorithm on low-dose 64-detector CT: comparison of iDose and filtered back projection].

To evaluate the usefulness of hybrid iterative reconstruction (iDose) for quantification of calcium content in the coronary artery on 64-detector computed tomography (CT), an anthropomorphic cardiac CT phantom containing cylinders with known calcium content was scanned at tube current-time products of 15, 20, 25, and 50 mAs using 64-detector CT. The images obtained at 15, 20, 25, and 50 mAs were reconstructed using filtered back projection (FBP), and those at 15, 20, and 25 mAs were also reconstructed using iDose. Then the volume and mass of the calcium content in the cylinders were calculated and compared with the true values.

Clinical usefulness of a collimator distance dependent resolution recovery in myocardial perfusion SPECT: a clinical report from a single institute.

Objective: Imperfect image resolution because of finite-sized collimator channels often causes a decrease in diagnostic performance in myocardial perfusion single-photon emission computed tomography (SPECT). This prompted us to evaluate the clinical usefulness of collimator distance dependent resolution recovery (RR) in myocardial perfusion SPECT.

Methods: We retrospectively reviewed myocardial SPECT images of 60 consecutive patients (26 men, 34 women; mean age 68 years).

[A fundamental study of non-contrast enhanced MR angiography using ECG gated-3D fast spin echo at 3.0 T].

Contrast-enhanced magnetic resonance angiography (CE-MRA) is frequently performed in body and extremity studies because of its superior ability to detect the vascular stenosis. However, nephrotoxicity of the contrast medium has been emphasized in recent years. Non-contrast MRA using the three-dimensional electrocardiogram-synchronized fast spin echo method (FBI, NATIVE and TRANCE) is recommended as a substitute for CE-MRA.