Ct doses

Para -aminohippurate, also known as p -aminohippuric acid (PAH), is used clinically to measure effective renal plasma flow. Preclinically, it was shown to reduce 177 Lu-DOTATOC uptake in the kidneys while improving bioavailability compared with amino acid (AA) coinfusion. We report the safety and efficacy of PAH coinfusion during peptide receptor radiotherapy in patients with neuroendocrine tumors. Methods: Twelve patients with metastatic or unresectable gastroenteropancreatic neuroendocrine tumors received 177 Lu-DOTATOC in 33 treatment cycles...

INTRODUCTION: Tuberculosis remains one of the top ten causes of mortality globally. Children accounted for 12% of all TB cases and 18% of all TB deaths in 2022. Paediatric TB is difficult to diagnose with conventional laboratory tests, and chest radiographs remain crucial. However, in low-and middle-income countries with high TB burden, the capacity for radiological diagnosis of paediatric TB is rarely documented and data on the associated radiation exposure limited. METHODS: A multicentre, mixed-methods study is proposed in three countries, Mozambique, South Africa and Spain...

Monte Carlo simulations using patient CT images as input are the gold standard to perform patient-specific dosimetry. However, in standard clinical practice patient's CT images are limited to the reconstructed CT scan range. In this study, organ dose calculations were performed with ImpactMC for chest and cardiac CT using whole-body and anatomy-specific voxel models to estimate the accuracy of CT organ doses based on the latter model. When the 3D patient model is limited to the CT scan range, CT organ doses from Monte Carlo simulations are the most accurate for organs entirely in the field of view...

PURPOSE: To compare the diagnostic approach of acute pulmonary embolism (PE) with photon-counting-detector CT (PCD-CT) and energy-integrating-detector CT (EID-CT). MATERIALS AND METHODS: Two cohorts underwent CT angiographic examinations with EID-CT (Group 1; n = 158) and PCD-CT (Group 2; n = 172), (b) with two options in Group 1, dual energy (Group 1a) or single energy (Group 1b) and a single option in Group 2 (spectral imaging with single source)...

BACKGROUND AND AIMS: Visceral obesity is a risk factor for reflux esophagitis (RE). We investigated the risk of RE according to visceral adipose tissue (VAT) measured by deep neural network architecture using computed tomography and evaluated the longitudinal association between abdominal adipose tissue changes and the disease course of RE. METHODS: Individuals receiving health checkups who underwent esophagogastroduodenoscopy (EGD) and abdominal computed tomography (CT) at Seoul National University Healthcare System Gangnam Center between 2015 and 2016 were included...

BACKGROUND: The antiviral drug Nirmatrelvir was found to be a key drug in controlling the progression of pneumonia during the infectious phase of COVID-19. However, there are very few options for effective treatment for cancer patients who have viral pneumonia. Glucocorticoids is one of the effective means to control pneumonia, but there are many adverse events. EGCG is a natural low toxic compound with anti-inflammatory function. Thus, this study was designed to investigate the safety and efficacy of epigallocatechin-3-gallate (EGCG) aerosol to control COVID-19 pneumonia in cancer populations...

INTRODUCTION: The currently available dosimetry techniques in computed tomography can be inaccurate which overestimate the absorbed dose. Therefore, we aimed to provide an automated and fast methodology to more accurately calculate the SSDE using D_w obtained by using CNN from thorax and abdominal CT study images. METHODS: The SSDE was determined from the 200 records files. For that purpose, patients' size was measured in two ways: a) by developing an algorithm following the AAPM Report No...

In drinking water applications, an ozone exposure (Ct) based framework has been historically used to validate ozone disinfection. However, significant viral inactivation can be achieved with little to no measurable ozone exposure. Additionally, ozone exposure depends on multiple water quality variables as well as the calculation/ozone measurement method used. In this study, we evaluated alternative ozone monitoring frameworks as well as the impact of water quality variables on ozone decay kinetics and virus/coliform inactivation...

A 69-year-old man diagnosed with progressive bone metastatic castration-resistant prostate adenocarcinoma and concurrent alcoholic cirrhosis with multiple hepatocellular carcinoma (HCC) nodules was referred to our nuclear medicine service for 177Lu-PSMA-617 therapy. The patient's pretreatment screening using 68Ga-PSMA-11 PET/CT revealed high prostate-specific membrane antigen expression in both prostatic and HCC lesions. The patient underwent 2 doses of 177Lu-PSMA-617. Subsequent imaging assessments with 68Ga-PSMA-11 PET/CT and hepatic MRI indicated progressive HCC nodules, while showing a partial response in prostatic bone metastases...

Many oncology antibody-drug conjugates (ADCs) have failed to demonstrate efficacy in clinic because of dose-limiting toxicity caused by uptake into healthy tissues. We developed an approach that harnesses ADC affinity to broaden the therapeutic index (TI) using two anti-mesenchymal-epithelial transition factor (MET) monoclonal antibodies (mAbs) with high affinity (HAV) or low affinity (LAV) conjugated to monomethyl auristatin E (MMAE). The estimated TI for LAV-ADC was at least 3 times greater than the HAV-ADC...

BACKGROUND: Dynamic myocardial computed tomography perfusion (CTP) is a novel imaging technique that increases the applicability of CT for cardiac imaging; however, the scanning requires a substantial radiation dose. PURPOSE: To investigate the feasibility of dose reduction in dynamic CTP by comparing all-heartbeat acquisitions to periodic skipping of heartbeats. MATERIAL AND METHODS: We retrieved imaging data of 38 dynamic CTP patients and created new datasets with every fourth, third or second beat (Skip1:4, Skip1:3, Skip1:2, respectively) removed...

PURPOSE: To compare the inter-reader agreement of pancreatic adenocarcinoma resectability assessment at pancreatic protocol photon-counting CT (PCCT) with conventional energy-integrating detector CT (EID-CT). METHODS: A retrospective single institution database search identified all contrast-enhanced pancreatic mass protocol abdominal CT performed at an outpatient facility with both a PCCT and EID-CT from 4/11/2022 to 10/30/2022. Patients without pancreatic adenocarcinoma were excluded...

BACKGROUND: Fetal adenocarcinoma is a very rare subtype of lung adenocarcinoma. Its incidence ranges from 0.1 to 0.87% among all primary lung neoplasms. Low-grade types tend to appear in the younger generation, and the age ranges from 20 to 50 years with a mean age of around 35 years. Surgical resection is currently the best way to treat fetal adenocarcinoma lung cancer without distant metastasis. CASE REPORT: This is a 56-year-old female who underwent low-dose computer tomography (LDCT) screening during the health examination...

OBJECTIVE: To evaluate the clinical and imaging characteristics of SARS-CoV-2 breakthrough infection in hospitalized immunocompromised patients in comparison with immunocompetent patients. MATERIALS AND METHODS: This retrospective study analyzed consecutive adult patients hospitalized for COVID-19 who received at least one dose of the SARS-CoV-2 vaccine at two academic medical centers between June 2021 and December 2022. Immunocompromised patients (with active solid organ cancer, active hematologic cancer, active immune-mediated inflammatory disease, status post solid organ transplantation, or acquired immune deficiency syndrome) were compared with immunocompetent patients...

OBJECTIVE: This study evaluates various craniospinal irradiation (CSI) techniques used in Turkish centers to understand their advantages, disadvantages and overall effectiveness, with a focus on enhancing dose distribution. METHODS: Anonymized CT scans of adult and pediatric patients, alongside target volumes and organ-at-risk (OAR) structures, were shared with 25 local radiotherapy centers. They were tasked to develop optimal treatment plans delivering 36 Gy in 20 fractions with 95% PTV coverage, while minimizing OAR exposure...

Medication-related osteonecrosis of the jaw (MRONJ) poses a challenging form of osteomyelitis in patients undergoing antiresorptive therapies in contrast to conventional osteomyelitis. This study aimed to compare the clinical and radiological features of MRONJ between patients receiving low-dose medications for osteoporosis and those receiving high-dose medications for oncologic purposes. The clinical, panoramic radiographic, and computed tomography data of 159 patients with MRONJ (osteoporotic group, n = 120; oncologic group, n = 39) who developed the condition after using antiresorptive medications for the management of osteoporosis or bone malignancy were analyzed...

The diagnostic reference level (DRL) is a patient-exposure optimization tool used to evaluate radiation doses in medical imaging and provide guidance for protection from them. In Thailand, nuclear medicine DRLs have not been established yet. Therefore, this study surveyed dose levels in routine nuclear medicine procedures to provide national DRLs (NDRLs). Methods: NDRLs in Thailand were established by investigating the administered activity of radiopharmaceuticals in nuclear medicine examination studies. The NDRLs were determined on the basis of the 75th percentile (third quartile) of administered activity distribution as recommended by the International Commission on Radiological Protection...

The foreseen increasing application of copper-based nanomaterials (Cu-NMs), replacing or complementing existing Cu-agrochemicals, may negatively impact the soil microbiome. Thus, we studied the effects on soil microbiome function and composition of nano copper oxide (nCuO) or copper hydroxide NMs in a commercial (Kocide®3000) or a lab-synthetized formulation (nCu(OH)2 ) or bulk copper hydroxide (Cu(OH)2 -B), at the commonly recommended Cu dose of 50 mg(Cu)kg-1 soil. Microbial responses were studied over 28 days in a designed indoor mesocosm...

BACKGROUND: Anti-synthetase syndrome (AS) is a rare autoimmune idiopathic inflammatory myopathy (IIM) with diverse manifestations, including arthritis, interstitial lung disease (ILD), Raynaud's phenomenon, unexplained persistent fever, and mechanic's hands. CASE PRESENTATION: We present the case of a 72-year-old woman, previously healthy, who was admitted to our hospital for treatment of cough and rapid breathing. The patient had elevated white blood cells and C-reactive protein, and tested negative for severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2)...

Convolutional neural networks (CNN) have been used for a wide variety of deep learning applications, especially in computer vision. For medical image processing, researchers have identified certain challenges associated with CNNs. These challenges encompass the generation of less informative features, limitations in capturing both high and low-frequency information within feature maps, and the computational cost incurred when enhancing receptive fields by deepening the network. Transformers have emerged as an approach aiming to address and overcome these specific limitations of CNNs in the context of medical image analysis...