Global and Regional Reduction of Myocardial Perfusion in Patients with Transthyretin Type of Cardiac Amyloidosis: A Dual SPECT Study Using Tc Pyrophosphate and Thallium.

: We aimed to clarify the clinical characteristics of global and regional myocardial perfusion in patients with transthyretin type of cardiac amyloidosis (ATTR) using dual single-photon emission computed tomography (SPECT) with Tc pyrophosphate (PYP) and TL (TL). : Consecutive 178 (mean age 78±12, male 79) patients known or suspect of ATTR who underwent PYP-TL dual SPECT were retrospectively enrolled. Patients were categorized according to the visual grading for planar PYP uptake using Perugini grading, and the patients with grade greater than or equal to 2 were analyzed.

A Quantitative Diagnostic Method Using Tc-pyrophosphate Lateral Planar Images to Distinguish Between Transthyretin Amyloid Cardiomyopathy and False-Positive Images Due to Blood Pools.

: This study investigated the feasibility of using a quantitative diagnostic method based on Tc-pyrophosphate scintigraphy (PYP) lateral planar images to differentiate between PYP-positive (myocardial uptake) and false-positive (blood pool uptake) scans. : The study included 93 consecutive patients with suspected transthyretin amyloid cardiomyopathy (ATTR-CM) who underwent PYP between April 2022 and December 2023. Patients were categorized using planar anterior PYP images according to the Perugini visual grading system; patients with grades ≥ 2 were analyzed.

Evaluation of pharmacokinetics, safety, and efficacy of [211At] meta-astatobenzylguanidine ([211At] MABG) in patients with pheochromocytoma or paraganglioma (PPGL): A study protocol.

Background: Pheochromocytoma, or paraganglioma (PPGL), is a tumor that arises from catecholamine-producing chromaffin cells of the adrenal medulla or paraganglion. Systemic therapy, such as the combination of cyclophosphamide, vincristine, and dacarbazine or therapeutic radiopharmaceuticals such as [131I] meta-iodobenzylguanidine (MIBG), may be administered in cases of locally advanced tumors or distant metastases. However, the current therapies are limited in terms of efficacy and implementation.

Impact of iodine contrast media on gamma camera-based GFR and factors affecting the difference between serum creatinine-based estimated GFR and Gate's GFR.

Objective: We aimed to elucidate the factors underlying the difference between estimated glomerular filtration rate (eGFR) calculated from serum creatinine and Gate's GFR (gGFR) measured using technetium-99m diethylene triamine pentaacetic acid ( 99m Tc-DTPA) scintigraphy.

Methods: This study was based on consecutive patients who underwent 99m Tc-DTPA scintigraphy at our hospital between January 2021 and December 2022 and whose blood serum creatinine data were obtained on the same day as the 99m Tc-DTPA scintigraphy. Relationships between the ratio of gGFR and eGFR (gGFR/eGFR) and age, sex, BMI, visceral fat, psoas muscle index (PMI), serum blood urea nitrogen, and creatinine level were investigated based on 75 patients.

Investigation of factors affecting CT attenuation and glucose metabolism of bone marrow as seen on PET/CT scans.

The aim of this study is to determine the factors affecting the CT attenuation of bone marrow, and its correlation with F-FDG uptake. The mean standardized uptake value (SUV) of vertebral bone marrow (Vertebral-SUV) and femoral bone marrow (Femoral-SUV) as well as CT number of bone marrow (BM-CT number) were measured in 243 patients who had undergone F-FDG PET/CT. The correlations among BM-CT number, Femoral-SUV, and Vertebral-SUV were investigated.

The Relationship Between Conventionally Obtained Serum-Based Liver Function Indices and Intravoxel Incoherent Motion Diffusion-Weighted Imaging and Magnetic Resonance Elastography in Patients With Hepatocellular Carcinoma.

Objectives: To investigate the relationship between conventionally obtained serum-based biochemical indices and intravoxel incoherent motion imaging (IVIM) parameters compared with magnetic resonance elastography (MRE).

Methods: Patients with hepatocellular carcinoma who underwent ≥2 liver magnetic resonance imaging (MRI) scan, including IVIM and MRE, between 2017 and 2020 and biochemical testing within 1 week before or after MRI were included in this study. Biochemical tests were performed to determine the albumin-bilirubin (ALBI) score and modified ALBI (mALBI) grade, aspartate aminotransferase to platelet ratio index (APRI), and fibrosis-4 index (FIB-4).

Investigation of tumor assessment between two PET systems using various indices: comparison between PET/CT and PET/MRI systems.

This study aimed to determine the comparability of tumor-uptake indices of F-FDG in positron emission tomography/computed tomography (PET/CT) and positron emission tomography/magnetic resonance imaging (PET/MRI). 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG) PET/CT and PET/MRI were performed on 55 patients with confirmed primary malignancies. PET/CT preceded PET/MRI in all examinations.

Incidence of Bowel Wall Swelling Induced by Iodine-Contrast Media and Its Association With Gastrointestinal Manifestation.

Purpose: The aim of this study was to investigate the incidence of bowel wall swelling after iodine-contrast media injection and its relationship with gastrointestinal symptoms.

Methods: The incidence of bowel wall swelling was examined in 75 patients who showed adverse reactions to iodine-contrast media (AR[+] group) and 75 controls without adverse reactions (AR[-] group). Bowel wall swelling was identified if there was increased wall thickness on postcontrast computed tomography when compared with precontrast computed tomography.

Novel nomogram developed for determining suitability of metastatic castration-resistant prostate cancer patients to receive maximum benefit from radium-223 dichloride treatment-Japanese Ra-223 Therapy in Prostate Cancer using Bone Scan Index (J-RAP-BSI) Trial.

Purpose: To develop a novel nomogram for determining radium-223 dichloride (Ra-223) treatment suitability for metastatic castration-resistant prostate cancer (mCRPC) patients.

Methods: This Japanese Ra-223 Therapy in Prostate Cancer using Bone Scan Index (J-RAP-BSI) Trial was a retrospective multicenter investigation enrolled 258 mCRPC patients in Japan with Ra-223 treatment between June 2016 and August 2020, with bone scintigraphy findings before treatment, clinical data, and survival outcome available. A nomogram was constructed using prognostic factors for overall survival (OS) based on a least absolute shrinkage and selection operator Cox regression model.

Evaluation of Computed Tomography Attenuation Value of Proximal Femoral Marrow to Diagnose and Differentiate Hematologic Malignancies, Myelofibrosis, and Aplastic Anemia.

Objective: The aim of this study was to diagnose hematologic diseases using computed tomography (CT) number of proximal femoral marrow.

Methods: The average CT number of marrow in hematologic diseases was measured on the caudal side of the greater trochanter.

Results: The CT numbers were -60.

Hypertrophic Pachymeningitis Demonstrated by Whole-Body 67Ga Scintigraphy.

Hypertrophic pachymeningitis is a rare inflammatory process characterized by thickening of the dura mater that can be idiopathic or secondary to a variety of conditions such as ANCA-related vasculitis, IgG4-related disease, Sjögren syndrome, rheumatoid arthritis, sarcoidosis, and infections. It can cause various neurological alterations such as headache, cranial nerve disorder, cerebellar disorder, sensory impairment, and weakness. Brain MRI is useful for imaging diagnosis of hypertrophic pachymeningitis, showing focal thickening and enhancement of the dura mater.

Usefulness of Model-Based Iterative Reconstruction in Brain CT as Compared With Hybrid Iterative Reconstruction.

Objective: The aim of this study was to compare the contrast of gray to white matter between forward-projected model-based iterative reconstruction solution (FIRST) and hybrid iterative reconstruction (IR) by measuring computed tomography value of brain parenchyma.

Methods: Computed tomography values of the gray and white matter in 15 areas of 21 patients (7 males, 14 females; average age, 49.5 ± 10.

Integrated PET/MRI scanner with oxygen-15 labeled gases for quantification of cerebral blood flow, cerebral blood volume, cerebral oxygen extraction fraction and cerebral metabolic rate of oxygen.

Objectives: Measurement of cerebral blood flow (CBF), cerebral blood volume (CBV), cerebral oxygen extraction fraction (OEF) and cerebral metabolic rate of oxygen (CMRO) by PET with oxygen-15 labeled gases is useful for diagnosis and treatment planning in cases of chronic occlusive cerebrovascular disease. In the present study, CBF, CBV, OEF and CMRO were measured using the integrated design of PET/MRI scanner system. This is a first attempt to measure cerebral perfusion and oxygen metabolism using PET/MRI with oxygen-15 labeled gases.

Positron Emission Tomography for Response Evaluation in Microenvironment-Targeted Anti-Cancer Therapy.

Therapeutic response is evaluated using the diameter of tumors and quantitative parameters of 2-[F] fluoro-2-deoxy-d-glucose positron emission tomography (FDG-PET). Tumor response to molecular-targeted drugs and immune checkpoint inhibitors is different from conventional chemotherapy in terms of temporal metabolic alteration and morphological change after the therapy. Cancer stem cells, immunologically competent cells, and metabolism of cancer are considered targets of novel therapy.

Causes of false negatives in technetium-99 m methoxyisobutylisonitrile scintigraphy for hyperparathyroidism: influence of size and cysts in parathyroid lesions.

Objective: The aim of this study was to elucidate the causes of false-negative cases of technetium-99 m methoxyisobutylisonitrile scintigraphy (MIBI) for hyperparathyroidism.

Methods: Consecutive MIBI examinations performed in 154 patients between April 2011 and March 2017 were retrospectively reviewed. Sensitivities of MIBI, CT and US were calculated.

Feasibility of gamma camera-based GFR measurement using renal depth evaluated by lateral scan of Tc-DTPA renography.

Objective: Gamma camera-based measurement of glomerular filtration rate (GFR) with Tc-diethylenetriaminepentaacetic acid (DTPA) is an established non-invasive measurement of split renal function; however, it is not as accurate as the plasma sample method. Therefore, study into improving the accuracy of such method is clinically relevant. The aim of this study was to elucidate the feasibility of gamma camera-based GFR measurement using renal depth evaluated by lateral scan of Tc-DTPA renography and comparing the results with those of GFR using renal depth measured by CT, and three representative formulas.

Detectability of Malignant Lesions by Whole-Body Magnetic Resonance Imaging Using Whole-Body Integrated Positron Emission Tomography/Magnetic Resonance Imaging.

Purpose: To assess the diagnostic ability of whole-body magnetic resonance imaging (MRI) using integrated positron emission tomography/MRI(PET/MRI).

Methods: Axial T2-weighted image (T2WI), diffusion-weighted imaging (DWI), coronal T1-weighted image (T1WI), axial volumetric interpolated breath-hold examination in the lung field, and 2-[fluorine-18]-fluoro-2-deoxy-D-glucose (FDG-PET) were evaluated in combination with T2WI alone, T2WI + DWI, T2WI + DWI + T1WI, T2WI + DWI + T1WI + volumetric interpolated breath-hold examination (all MRI images), and all MRI + FDG-PET.

Results: A total of 370 lesions were observed in 90 (62.

Optimized workflow and imaging protocols for whole-body oncologic PET/MRI.

Although PET/MRI has the advantages of a simultaneous acquisition of PET and MRI, high soft-tissue contrast of the MRI images, and reduction of radiation exposure, its low profitability and long acquisition time are significant problems in clinical settings. Thus, MRI protocols that meet oncological purposes need to be used in order to reduce examination time while securing detectability. Currently, half-Fourier acquisition single-shot turbo spin echo and 3D-T1 volumetric interpolated breath-hold examination may be the most commonly used sequences for whole-body imaging due to their shorter acquisition time and higher diagnostic accuracy.