Diffuse Infiltrative Non-mass-like Brain Parenchymal Lesions on MRI: Differentiating Lymphomatosis Cerebri from its Mimics

Objectives: Diffuse infiltrative “non-mass-like” parenchymal lesions on MRI brain are a known presentation of an aggressive condition called lymphomatosis cerebri (LC) but are often misdiagnosed due to its non-specific clinical and imaging findings. We aim to identify clues to differentiate lymphomatosis from its less aggressive mimics based on imaging features. Material and Methods: MRI brain studies showing diffuse infiltrative “non-mass-like” parenchymal lesions between January 2013 and March 2020 were retrospectively identified and read for lesion location, signal characteristics, and enhancement pattern by two radiologists. Additional findings on MRI spine and whole-body fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) were recorded wherever available. The clinical diagnosis, patient demographics, symptoms, laboratory and histopathology results, treatment details, and follow-up details were also noted. Results: Of the 67 patients, 28 (41.7%) were diagnosed with lymphomatosis. The remaining 39 (13.4%) patients were classified as non-lymphomas (infective, vasculitis, and inflammatory conditions). Diffusion restriction on MRI (20/67, P = 0.007) and increased regional activity on FDG PET-CT (12/31, P = 0.017) were the two imaging parameters found to significantly favor lymphomatosis over other conditions, whereas the presence of microhemorrhages on susceptibility-weighted imaging was significantly associated with vasculitis (P = 0.002). Rapid clinical or imaging deterioration on a short trial of steroids (P = 0.00) was the only relevant clinical factor to raise an early alarm of lymphomatosis. Positive serological markers and non-central nervous system systemic diseases were associated with non-lymphomatous diseases. Conclusion: LC and its less aggressive mimics can be differentiated on diffusion-weighted imaging-MRI and PET-CT when read in conjunction with rapid progression of clinical features, serological workup, and systemic evaluation.

Download Full-text

FDG-PET/CT Assessment of Pulmonary Sarcoidosis: A Guide for Internists

Current Medical Imaging Formerly Current Medical Imaging Reviews ◽

10.2174/1573405614666180528101755 ◽

2018 ◽

Vol 15 (1) ◽

pp. 21-25 ◽

Cited By ~ 1

Author(s):

Marco Tana ◽

Silvio di Carlo ◽

Marcello Romano ◽

Massimo Alessandri ◽

Cosima Schiavone ◽

...

Keyword(s):

Computed Tomography ◽

Fdg Pet ◽

Correct Diagnosis ◽

Pulmonary Sarcoidosis ◽

High Resolution Computed Tomography ◽

Inflammatory Conditions ◽

Positron Emission ◽

Pet Ct ◽

Noncaseating Granulomas ◽

Fdg Pet Ct

Background:18F-fluorodeoxyglucose positron emission tomography integrated with computed tomography (18-F-FDG-PET/CT) is getting wide consensus in the diagnosis and staging of neoplastic disorders and represents a useful tool in the assessment of various inflammatory conditions. </P><P> Discussion: Sarcoidosis is an uncommon disease characterized by the systemic formation of noncaseating granulomas. Lungs are the sites most often affected, and investigation with high resolution computed tomography and biopsy is essential to achieve a correct diagnosis. 18-F-FDGPET/ CT is effective in the assessment of pulmonary sarcoidosis by demonstrating pulmonary and extrathoracic involvement and findings correlate well with pulmonary function in patients affected.Conclusion:This review would illustrate the usefulness and limits of 18-F-FDG-PET/CT in the assessment of pulmonary sarcoidosis.

Download Full-text

POSITRON EMISSION TOMOGRAPHY WITH 18F -FDG IN THE DIAGNOSIS OF PROSTHETIC HEART VALVE ENDOCARDITIS

Emergency Cardiology and Cardiovascular Risks ◽

10.51922/2616-633x.2021.5.2.1151 ◽

2021 ◽

Vol 5 (1) ◽

pp. 1151-1160

Author(s):

A.S. Lukashevich ◽

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Fdg Pet ◽

Prosthetic Heart Valve ◽

Emission Tomography ◽

Whole Body ◽

Positron Emission ◽

Pet Ct ◽

18F Fdg ◽

Fdg Pet Ct

Purpose. The purpose of the article is to evaluate the diagnostic significance of positron emission tomography / computed tomography with 18F -fluorodeoxyglucose (18F -FDG PET/CT) for the diagnosis of prosthetic endocarditis. Methods of research. The study included 82 patients with suspected prosthetic endocarditis in accordance with the criteria proposed by Duke University [1-5]. The patients received hospital treatment at the State Institution RSPC "Cardiology" from January 2016 to March 2021. The study was of a prospective, non-randomized, single-center cohort design. The duration of the monitor period was 12 months from the moment of patients’ inclusion in the study. Whole-body positron emission tomography / computed tomography (PET/CT) examinations were performed in 82 patients. 27 patients were selected for surgical treatment. Conservative treatment group included 16 patients. 27 patients were selected into the observation group, they were suspected to have prosthetic heart valve infection in the primary referral and underwent PET/CT scanning, according to which the diagnosis of prosthetic endocarditis was excluded. The event under the study did not develop in this group during the year of observation. Results and conclusion. The history of infective endocarditis was not statistically significant and did not increase the risk of developing prosthetic endocarditis in the sample presented. The Duke criteria are less reliable in establishing the diagnosis of prosthetic endocarditis. The median number of days from the date of the first prosthesis implantation to the onset of prosthetic endocarditis was about 4 years. This study revealed that the development of the infectious process in the area of the prosthesis was noted in a more distant postoperative period compared to literature data. Histological confirmation of infection was noted in 100% (27 patients) of cases in reoperated patients. The presence of a more formidable complication such as valve ring abscess located mainly in the projection of the aortic valve ring was quite common in both groups. Presepsin and Interleukin-6 have a statistically significant (U = 394,50 p = 0,01 and U = 94,50 p = 0.004) value in the prognosis of prosthetic endocarditis. Considering the data obtained from ROC analysis, it can be said that the cut-off point at which it is possible to diagnose prosthetic endocarditis based on PETCT is 2.85. The presented methods for the interpretation of whole-body FDG-PET/CT images of patients with suspected infectious complications after cardiac surgery, as well as with the presence of prosthetic endocarditis, show high sensitivity and specificity.

Download Full-text

Imaging Enterobacterales infections in patients using pathogen-specific positron emission tomography

Science Translational Medicine ◽

10.1126/scitranslmed.abe9805 ◽

2021 ◽

Vol 13 (589) ◽

pp. eabe9805

Author(s):

Alvaro A. Ordonez ◽

Luz M. Wintaco ◽

Filipa Mota ◽

Andres F. Restrepo ◽

Camilo A. Ruiz-Bedoya ◽

...

Keyword(s):

Positron Emission Tomography ◽

Solid Phase ◽

Multidrug Resistant ◽

Sterile Inflammation ◽

Emission Tomography ◽

Whole Body ◽

Hamster Model ◽

Positron Emission ◽

Pet Ct

Enterobacterales represent the largest group of bacterial pathogens in humans and are responsible for severe, deep-seated infections, often resulting in sepsis or death. They are also a prominent cause of multidrug-resistant (MDR) infections, and some species are recognized as biothreat pathogens. Tools for noninvasive, whole-body analysis that can localize a pathogen with specificity are needed, but no such technology currently exists. We previously demonstrated that positron emission tomography (PET) with 2-deoxy-2-[18F]fluoro-d-sorbitol (18F-FDS) can selectively detect Enterobacterales infections in murine models. Here, we demonstrate that uptake of 18F-FDS by bacteria occurs via a metabolically conserved sorbitol-specific pathway with rapid in vitro 18F-FDS uptake noted in clinical strains, including MDR isolates. Whole-body 18F-FDS PET/computerized tomography (CT) in 26 prospectively enrolled patients with either microbiologically confirmed Enterobacterales infection or other pathologies demonstrated that 18F-FDS PET/CT was safe, could rapidly detect and localize Enterobacterales infections due to drug-susceptible or MDR strains, and differentiated them from sterile inflammation or cancerous lesions. Repeat imaging in the same patients monitored antibiotic efficacy with decreases in PET signal correlating with clinical improvement. To facilitate the use of 18F-FDS, we developed a self-contained, solid-phase cartridge to rapidly (<10 min) formulate ready-to-use 18F-FDS from commercially available 2-deoxy-2-[18F]fluoro-d-glucose (18F-FDG) at room temperature. In a hamster model, 18F-FDS PET/CT also differentiated severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pneumonia from secondary Klebsiella pneumoniae pneumonia—a leading cause of complications in hospitalized patients with COVID-19. These data support 18F-FDS as an innovative and readily available, pathogen-specific PET technology with clinical applications.

Download Full-text

Exposure Doses to Technologists Working in 7 PET/CT Departments

Dose-Response ◽

10.1177/1559325820938288 ◽

2020 ◽

Vol 18 (3) ◽

pp. 155932582093828

Author(s):

Weiguo Li ◽

Lianying Fang ◽

Jieqing Li

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Occupational Exposure ◽

Emission Tomography ◽

Whole Body ◽

Average Dose ◽

Protective Measures ◽

Positron Emission ◽

Pet Ct ◽

Main Population

Objective: The aim of this study was to measure occupational exposure doses of technologists who dispense and inject radiopharmaceuticals in 7 positron emission tomography/computed tomography (PET/CT) departments. This was done with the goal to help improving protective designs in PET departments and/or establishing national protection standards. Method: Common LiF thermoluminescence dosimeters (TLDs) were placed on the chest and necklace of the technologists to monitor whole-body and thyroid doses, respectively. Ring TLDs were also worn on both index fingers to measure individual hand doses. All TLDs were assembled and measured once every 3 months for a total of 12 months. Additionally, we measured and compared the dose of TLDs attached to both the inside and the outside of the technologist’s lead coat. Results: Technologists received relatively high exposures, which accounted for 64% to 94% of the collective dose in their respective departments. Their thyroid doses ranged from 1.2 to 1.7 mSv/a; some technologists’ hand doses exceeded 500 mSv/a. Use of a lead coat reduced the average dose by 8%. Conclusion: Technologists working in PET/CT departments were the main population exposed to radiation. This work underscores the need for enhanced protective measures for these workers to better reduce their exposure, particularly for their hands.

Download Full-text

Texture Analysis in the Diagnosis of Primary Breast Cancer: Comparison of High-Resolution Dedicated Breast Positron Emission Tomography (dbPET) and Whole-Body PET/CT

Frontiers in Medicine ◽

10.3389/fmed.2020.603303 ◽

2020 ◽

Vol 7 ◽

Author(s):

Yoko Satoh ◽

Kenji Hirata ◽

Daiki Tamada ◽

Satoshi Funayama ◽

Hiroshi Onishi

Keyword(s):

Breast Cancer ◽

Positron Emission Tomography ◽

High Resolution ◽

Texture Analysis ◽

Texture Features ◽

Emission Tomography ◽

Whole Body ◽

Tumor Characteristics ◽

Positron Emission ◽

Pet Ct

Objective: This retrospective study aimed to compare the ability to classify tumor characteristics of breast cancer (BC) of positron emission tomography (PET)-derived texture features between dedicated breast PET (dbPET) and whole-body PET/computed tomography (CT).Methods: Forty-four BCs scanned by both high-resolution ring-shaped dbPET and whole-body PET/CT were analyzed. The primary BC was extracted with a standardized uptake value (SUV) threshold segmentation method. On both dbPET and PET/CT images, 38 texture features were computed; their ability to classify tumor characteristics such as tumor (T)-category, lymph node (N)-category, molecular subtype, and Ki67 levels was compared. The texture features were evaluated using univariate and multivariate analyses following principal component analysis (PCA). AUC values were used to evaluate the diagnostic power of the computed texture features to classify BC characteristics.Results: Some texture features of dbPET and PET/CT were different between Tis-1 and T2-4 and between Luminal A and other groups, respectively. No association with texture features was found in the N-category or Ki67 level. In contrast, receiver-operating characteristic analysis using texture features' principal components showed that the AUC for classification of any BC characteristics were equally good for both dbPET and whole-body PET/CT.Conclusions: PET-based texture analysis of dbPET and whole-body PET/CT may have equally good classification power for BC.

Download Full-text

Etiology of Solitary Extrapulmonary Positron Emission Tomography and Computed Tomography Findings in Patients With Lung Cancer

Journal of Clinical Oncology ◽

10.1200/jco.2005.10.116 ◽

2005 ◽

Vol 23 (28) ◽

pp. 6846-6853 ◽

Cited By ~ 87

Author(s):

Didier Lardinois ◽

Walter Weder ◽

Marina Roudas ◽

Gustav K. von Schulthess ◽

Michaela Tutic ◽

...

Keyword(s):

Computed Tomography ◽

Lung Cancer ◽

Positron Emission Tomography ◽

Ct Imaging ◽

Emission Tomography ◽

Whole Body ◽

Benign Tumors ◽

Positron Emission ◽

Pet Ct ◽

The Impact

Purpose The aim of this prospective study was to assess the incidence and the nature of solitary extrapulmonary [18F] fluorodeoxyglucose (FDG) accumulations in patients with non–small-cell lung cancer (NSCLC) staged with integrated positron emission tomography and computed tomography (PET/CT) and to evaluate the impact on management. Patients and Methods A total of 350 patients with NSCLC underwent whole-body PET/CT imaging. All solitary extrapulmonary FDG accumulations were evaluated by histopathology, further imaging, or clinical follow-up. Results PET/CT imaging revealed extrapulmonary lesions in 110 patients. In 72 patients (21%), solitary lesions were present. A diagnosis was obtained in 69 of these patients, including 37 (54%) with solitary metastases and 32 (46%) with lesions unrelated to the lung primary. Histopathologic examinations of these 32 lesions revealed a second clinically unsuspected malignancy or a recurrence of a previous diagnosed carcinoma in six patients (19%) and a benign tumor or inflammatory lesion in 26 patients (81%). The six malignancies consisted of carcinoma of the breast in two patients, and carcinoma of the orbit, esophagus, prostate, and non-Hodgkin's lymphoma in one patient each. Benign tumors and inflammatory lesions included eight colon adenomas, four Warthin's tumors, one granuloma of the lower jaw, one adenoma of the thyroid gland, one compensatory muscle activity due to vocal chord palsy, two occurrences of arthritis, three occurrences of reflux esophagitis, two occurrences of pancreatitis, two occurrences of diverticulitis, one hemorrhoidal inflammation, and one rib fracture. Conclusion Solitary extrapulmonary FDG accumulations in patients with newly diagnosed lung cancer should be analyzed critically for correct staging and optimal therapy, given that up to half of the lesions may represent unrelated malignancies or benign disease.

Download Full-text

Sex differences in pericardial adipose tissue assessed by PET/CT and association with cardiometabolic risk

Acta Radiologica ◽

10.1177/0284185118756950 ◽

2018 ◽

Vol 59 (10) ◽

pp. 1203-1209 ◽

Cited By ~ 5

Author(s):

Corey M Gill ◽

Debora C Azevedo ◽

Adriana L Oliveira ◽

Edgar L Martinez-Salazar ◽

Martin Torriani ◽

...

Keyword(s):

Sex Differences ◽

Adipose Tissue ◽

Operating Characteristic ◽

Cardiometabolic Risk ◽

Whole Body ◽

The Metabolic Syndrome ◽

Body Adiposity ◽

Positron Emission ◽

Pericardial Adipose Tissue ◽

Pet Ct

Background Recent studies suggest that pericardial adipose tissue (PAT) is associated with whole body adiposity and insulin resistance. Moreover, the incidence of cardiovascular disease (CVD) differs between men and women. Although CVD is more prevalent in men, women suffering from CVD have a higher mortality compared to men. Differences in PAT may account for some of the observed sex differences in manifestations of CVD. Purpose To assess pericardial adipose tissue (PAT) as a biomarker for cardiometabolic risk and to assess potential sex differences. Material and Methods We studied 303 individuals (151 women, 152 men; mean age = 57 ± 17 years) across the weight spectrum. PAT and abdominal adipose tissue were quantified using clinical computed tomography (CT) scans obtained as part of a positron emission tomography (PET)/CT. Cardiometabolic risk factors were assessed from medical records. Linear regression and receiver operating characteristic (ROC) curve analyses were performed to evaluate associations between PAT and cardiometabolic risk. Results PAT was higher in overweight and obese individuals compared to lean individuals and higher in men compared to women. PAT was positively associated with body mass index, abdominal fat ( P < 0.0001), fasting glucose, and serum lipids ( P < 0.05) with stronger associations in women than in men. PAT was accurate in detecting the prevalence of the metabolic syndrome with 74% sensitivity and 76% specificity (AUC = 0.80). Conclusion PAT is associated with measures of cardiometabolic risk and these associations are stronger in women compared to men. PAT could serve as a biomarker for opportunistic screening for cardiometabolic risk in patients undergoing chest CT.

Download Full-text

Incidence and Economic Impact of Incidental Findings on 18F-FDG PET/CT Imaging

Canadian Association of Radiologists Journal ◽

10.1016/j.carj.2017.08.001 ◽

2018 ◽

Vol 69 (1) ◽

pp. 63-70 ◽

Cited By ~ 7

Author(s):

Scott J. Adams ◽

Rajan Rakheja ◽

Rhonda Bryce ◽

Paul S. Babyn

Keyword(s):

Incidental Findings ◽

Incidental Finding ◽

Ct Imaging ◽

Whole Body ◽

Ontario Health Insurance Plan ◽

Positron Emission ◽

Pet Ct ◽

Picture Archiving And Communication ◽

Fdg Pet Ct

Purpose The study sought to determine the incidence of incidental findings on whole-body positron emission tomography with computed tomography (PET/CT) imaging and the average costs of investigations to follow-up or further characterize incidental findings. Methods Imaging reports of 215 patients who underwent whole-body PET/CT imaging were retrospectively reviewed. Our provincial picture archiving and communication system was queried and patient charts were reviewed to identify all investigations performed to follow-up incidental findings within 1 year of the initial PET/CT study. Costs of follow-up imaging studies (professional and technical components) and other diagnostic tests and procedures were determined in Canadian dollars (CAD) and U.S. dollars (USD) using the 2015 Ontario Health Insurance Plan Schedule of Benefits and Fees and 2016 U.S. Medicare Physician Fee Schedule, respectively. Results At least 1 incidental finding was reported in 161 reports (74.9%). The mean number of incidental findings ranged from 0.64 in patients <45 years of age to 2.2 in patients 75 years of age and older. Seventy-five recommendations for additional investigations were made for 64 (30%) patients undergoing PET/CT imaging, and 14 of those were carried out specifically to follow-up incidental findings. Averaged across all 215 patients, the total cost of investigations recommended to follow-up incidental findings was CAD$105.51 (USD$127.56) per PET/CT study if all recommendations were acted on, and CAD$22.77 (USD$29.14) based on investigations actually performed. Conclusions As the incidence of incidental findings increases with age and a larger proportion of elderly patients is expected as population demographics change, it will be increasingly important to consider incidental findings on PET/CT imaging with standardized approaches to follow-up.

Download Full-text

Comparison of the Diagnostic Value of MRI and Whole Body 18F-FDG PET/CT in Diagnosis of Spondylodiscitis

Journal of Clinical Medicine ◽

10.3390/jcm9051581 ◽

2020 ◽

Vol 9 (5) ◽

pp. 1581

Author(s):

Corinna Altini ◽

Valentina Lavelli ◽

Artor Niccoli-Asabella ◽

Angela Sardaro ◽

Alessia Branca ◽

...

Keyword(s):

Fdg Pet ◽

Diagnostic Value ◽

Whole Body ◽

Spine Infection ◽

Positron Emission ◽

Pet Ct ◽

18F Fdg ◽

Sensitivity Specificity ◽

Fdg Pet Ct ◽

Ct And Mri

Spondylodiscitis is a spine infection for which a diagnosis by a magnetic resonance imaging (MRI) is considered the most appropriate imaging technique. The aim of this study was to compare the role of an 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) and an MRI in this field. For 56 patients with suspected spondylodiscitis for whom MRI and 18F-FDG PET/CT were performed, we retrospectively analyzed the results. Cohen’s κ was applied to evaluate the agreement between the two techniques in all patients and in subgroups with a different number of spinal districts analyzed by the MRI. Sensitivity, specificity, and accuracy were also evaluated. The agreements of the 18F-FDG PET/CT and MRI in the evaluation of the entire population, whole-spine MRI, and two-districts MRI were moderate (κ = 0.456, κ = 0.432, and κ = 0.429, respectively). In patients for whom one-district MRI was performed, 18F-FDG PET/CT and MRI were both positive and completely concordant (κ = 1). We also separately evaluated patients with suspected spondylodiscitis caused by Mycobacterium tuberculosis for whom the MRI and 18F-FDG PET/CT were always concordant excepting in 2 of the 18 (11%) patients. Sensitivity, specificity, and accuracy of the MRI and 18F-FDG PET/CT were 100%, 60%, 97%, and 92%, 100%, and 94%, respectively. Our results confirmed the 18F-FDG PET/CT diagnostic value in the diagnosis of spondylodiscitis is comparable to that of MRI for the entire spine evaluation. This could be considered a complementary technique or a valid alternative to MRI.

Download Full-text

Positron Emission Tomography (PET) Radiopharmaceuticals in Multiple Myeloma

Molecules ◽

10.3390/molecules25010134 ◽

2019 ◽

Vol 25 (1) ◽

pp. 134 ◽

Cited By ~ 1

Author(s):

Christos Sachpekidis ◽

Hartmut Goldschmidt ◽

Antonia Dimitrakopoulou-Strauss

Keyword(s):

Computed Tomography ◽

Positron Emission Tomography ◽

Multiple Myeloma ◽

Bone Marrow ◽

Bone Disease ◽

Emission Tomography ◽

Whole Body ◽

Positron Emission ◽

Pet Ct ◽

18F Fdg

Multiple myeloma (MM) is a plasma cell disorder, characterized by clonal proliferation of malignant plasma cells in the bone marrow. Bone disease is the most frequent feature and an end-organ defining indicator of MM. In this context, imaging plays a pivotal role in the management of the malignancy. For several decades whole-body X-ray survey (WBXR) has been applied for the diagnosis and staging of bone disease in MM. However, the serious drawbacks of WBXR have led to its gradual replacement from novel imaging modalities, such as computed tomography (CT), magnetic resonance imaging (MRI) and positron emission tomography/computed tomography (PET/CT). PET/CT, with the tracer 18F-fluorodeoxyglucose (18F-FDG), is now considered a powerful diagnostic tool for the detection of medullary and extramedullary disease at the time of diagnosis, a reliable predictor of survival as well as the most robust modality for treatment response evaluation in MM. On the other hand, 18F-FDG carries its own limitations as a radiopharmaceutical, including a rather poor sensitivity for the detection of diffuse bone marrow infiltration, a relatively low specificity, and the lack of widely applied, established criteria for image interpretation. This has led to the development of several alternative PET tracers, some of which with promising results regarding MM detection. The aim of this review article is to outline the major applications of PET/CT with different radiopharmaceuticals in the clinical practice of MM.

Download Full-text