Hunting the Carotid Culprit An Intriguing Game:An Intriguing Game

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Role of Multimodal Imaging in Patients With Suspected Infections After the Bentall Procedure

Purpose: This study aimed to assess the diagnostic performances of multimodal imaging [i.e., white blood cell single-photon emission computed tomography/CT ((99m)Tc-HMPAO-WBC SPECT/CT) and 18-fluoride-fluorodeoxyglucose positron emission tomography/CT ([(18)F]FDG PET/CT)] in patients with suspected infection after the Bentall procedure, proposing new specific diagnostic criteria for the diagnosis. Methods: Between January 2009 and December 2019, we selected within a cardiovascular infections registry, 76 surgically treated patients (27 women and 49 men, median 66 years, and range 29–83 years). All the patients underwent molecular imaging for a suspected infection after the replacement of the aortic valve and ascending aorta according to the Bentall procedure. We analyzed 98 scans including 49 (99m)Tc-WBC and 49 [(18)F]FDG PET/CT. A total of 22 patients with very early/early suspected infection (<3 months after surgery) were imaged with both the techniques. Positive imaging was classified according to the anatomical site of increased uptake: to the aortic valve (AV), to both the AV and AV tube graft (AVTG) or to the TG, to surrounding tissue, and/or to extracardiac sites (embolic events or other sites of concomitant infection). Standard clinical workup included in all the patients having echocardiography/CT, blood culture, and the Duke criteria. Pretest probability and positive/negative likelihood ratio were calculated. Sensitivity and specificity of (99m)Tc labeled hexamethylpropylene amine oxime-WBC SPECT/CT ((99m)Tc-HMPAO-WBC SPECT/CT) and [(18)F]FDG PET/CT imaging were calculated by using microbiology (n = 35) or clinical follow-up (n = 41) as final diagnosis. (99m)Tc-HMPAO-WBC scintigraphy and [(18)F]FDG PET/CT findings were compared with 95% CIs by using the McNemar test to those of echocardiography/CT, blood culture, and the Duke criteria. Results: Sensitivity, specificity, and accuracy of (99m)Tc-HMPAO-WBC were 86, 92, and 88%, respectively, with a slightly higher sensitivity for tube graft infection (TGI) as compared to isolated AV and combined AVTG. Overall, sensitivity, specificity, and accuracy of [(18)F]FDG PET/CT were 97, 73, and 90%, respectively. In 22 patients with suspected very early and early postsurgical infections, the two imaging modalities were concordant in 17 cases [10 true positive (TP) and 7 true negative (TN)]. [(18)F]FDG PET/CT presented a higher sensitivity than (99m)Tc-HMPAO-WBC scan. (99m)Tc-HMPAO-WBC scan correctly classified as negative three false-positive (FP) PET/CT findings. Conclusion: Our findings supported the use of (99m)Tc-HMPAO-WBC SPECT/CT and [(18)F]FDG PET/CT in patients with suspicion infection after the Bentall procedure early in the course of the disease onset to confirm the diagnosis and provide a comprehensive assessment of disease burden through the proposed criteria

Relationship between F-18-FDG Uptake in the Oral Cavity, Recent Dental Treatments, and Oral Inflammation or Infection:A Retrospective Study of Patients with Suspected Endocarditis

[F-18]-fluorodeoxyglucose positron emission tomography ([F-18]FDG PET/CT) has proven to be a useful diagnostic tool in patients with suspected infective endocarditis (IE), but is conflicting in relation to dental procedures. Questions: Is there a correlation between [F-18]FDG PET/CT findings, recent dental treatment, and an affected oral cavity? (2) Is there a correlation between infective endocarditis (IE), oral health status, and (extra)cardiac findings on [F-18]FDG PET/CT? Methods: This retrospective study included 52 patients. All [F-18]FDG PET/CT scans were examined visually by pattern recognition using a three-point scale and semi-quantified within the volume of interest (VOI) using SUVmax. Results: 19 patients were diagnosed with IE (group 1), 14 with possible IE (group 2), and 19 without IE based on the modified Duke criteria (group 3). No correlation was found between visual PET and SUVmax and sites of oral inflammation and infection. The visual PET scores and SUVmax were not significantly different between all groups. A significant difference in the SUVmax of the valve between all groups was observed. Conclusions: This study suggests that no correlation exists between the PET findings in the oral cavity and dental treatments or inflammation/infection. No correlation between IE, actual oral health status, and extra-cardiac findings was demonstrated. Additional research is needed to conclude whether [F-18]FDG PET/CT imaging is a reliable diagnostic modality for oral inflammation and infection sites

Preclinical pharmacokinetics, biodistribution, radiation dosimetry and toxicity studies required for regulatory approval of a phase I clinical trial with 111In-CP04 in medullary thyroid carcinoma patients

Introduction: From a series of radiolabelled cholecystokinin (CCK) and gastrin analogues, 111In-CP04 (111In-DOTA-(DGlu)6-Ala-Tyr-Gly-Trp-Met-Asp-Phe-NH2) was selected for further translation as a diagnostic radiopharmaceutical towards a first-in-man study in patients with medullary thyroid carcinoma (MTC). A freeze-dried kit formulation for multicentre application has been developed. We herein report on biosafety, in vivo stability, biodistribution and dosimetry aspects of 111In-CP04 in animal models, essential for the regulatory approval of the clinical trial. Materials and methods: Acute and extended single dose toxicity of CP04 was tested in rodents, while the in vivo stability of 111In-CP04 was assessed by HPLC analysis of mouse blood samples. The biodistribution of 111In-CP04 prepared from a freeze-dried kit was studied in SCID mice bearing do

Cardiac molecular pathways influenced by doxorubicin treatment in mice

Doxorubicin (DOX) is a potent chemotherapeutic with distinct cardiotoxic properties. Understanding the underlying cardiotoxic mechanisms on a molecular level would enable the early detection of cardiotoxicity and implementation of prophylactic treatment. Our goal was to map the patterns of different radiopharmaceuticals as surrogate markers of specific metabolic pathways induced by chemotherapy. Therefore, cardiac distribution of Tc-99m-sestamibi, Tc-99m-Annexin V, Tc-99m-glucaric acid and [F-18]FDG and cardiac expression of Bcl-2, caspase-3 and -8, TUNEL, HIF-1 alpha, and p53 were assessed in response to DOX exposure in mice. A total of 80 mice (64 treated, 16 controls) were evaluated. All radiopharmaceuticals showed significantly increased uptake compared to controls, with peak cardiac uptake after one (Tc-99m-Annexin V), two (Tc-99m-sestamibi), three ([F-18]FDG), or four (Tc-99m-glucaric acid) cycles of DOX. Strong correlations (p <0.01) were observed between Tc-99m-Annexin V, caspase 3 and 8, and TUNEL, and between [F-18]FDG and HIF-1 alpha. This suggests that the cardiac DOX response starts with apoptosis at low exposure levels, as indicated by Tc-99m-Annexin V and histological apoptosis markers. Late process membrane disintegration can possibly be detected by Tc-99m-sestamibi and Tc-99m-glucaric acid. [F-18]FDG signifies an early adaptive response to DOX, which can be further exploited clinically in the near future