Atherosclerosis imaging with 18F-sodium fluoride PET: state-of-the-art review

Purpose: We examined the literature to elucidate the role of 18F-sodium fluoride (NaF)-PET in atherosclerosis. Methods: Following a systematic search of PubMed/MEDLINE, Embase, and Cochrane Library included articles underwent subjective quality assessment with categories low, medium, and high. Of 2811 records, 1780 remained after removal of duplicates. Screening by title and abstract left 41 potentially eligible full-text articles, of which 8 (about the aortic valve (n = 1), PET/MRI feasibility (n = 1), aortic aneurysms (n = 1), or quantification methodology (n = 5)) were dismissed, leaving 33 published 2010-2012 (n = 6), 2013-2015 (n = 11), and 2016-2018 (n = 16) for analysis. Results: They focused on coronary (n = 8), carotid (n = 7), and femoral arteries (n = 1), thoracic aorta (n = 1), and infrarenal aorta (n = 1). The remaining 15 studies examined more than one arterial segment. The literature was heterogeneous: few studies were designed to investigate atherosclerosis, 13 were retrospective, 9 applied both FDG and NaF as tracers, 24 NaF only. Subjective quality was low in one, medium in 13, and high in 19 studies. The literature indicates that NaF is a very specific tracer that mimics active arterial wall microcalcification, which is positively associated with cardiovascular risk. Arterial NaF uptake often presents before CT-calcification, tends to decrease with increasing density of CT-calcification, and appears, rather than FDG-avid foci, to progress to CT-calcification. It is mainly surface localized, increases with age with a wide scatter but without an obvious sex difference. NaF-avid microcalcification can occur in fatty streaks, but the degree of progression to CT-calcification is unknown. It remains unknown whether medical therapy influences microcalcification. The literature held no therapeutic or randomized controlled trials. Conclusion: The literature was heterogeneous and with few clear cut messages. NaF-PET is a new approach to detect and quantify microcalcification in early-stage atherosclerosis. NaF uptake correlates with cardiovascular risk factors and appears to be a good measure of the body's atherosclerotic burden, potentially suited also for assessment of anti-atherosclerotic therapy

Comparison of the diagnostic performance of CT colonography interpreted by radiologists and radiographers

OBJECTIVE: To compare computed tomographic colonography (CTC) performance of four trained radiographers with the CTC performance of two experienced radiologists. METHODS: Four radiographers and two radiologists interpreted 87 cases with 40 polyps ≥6 mm. Sensitivity, specificity, and positive predictive value (PPV) were assessed on a per-patient basis. On a per-polyp basis, sensitivity was calculated according to the respective size categories (polyps ≥6 mm as well as polyps ≥10 mm). RESULTS: Overall per-patient sensitivity for polyps ≥6 mm was 76.2 % (95 % CI 61.4–91.0) and 76.2 % (95 % CI 61.7–90.6), for the radiographers and radiologists, respectively. Overall per-patient specificity for polyps ≥6 mm were 81.4 % (95 % CI 73.7–89.2) and 81.1 % (95 % CI 73.8–88.3) for the radiographers and the radiologists, respectively. For the radiographers, overall per-polyp sensitivity was 60.3 % (95 % CI 50.3–70.3) and 60.7 % (95 % CI 42.2–79.2) for polyps ≥6 mm and ≥10 mm, respectively. For the radiologists, overall per polyp sensitivity was 59.2 % (95 % CI 46.4–72.0) and 69.0 % (95 % CI 48.1–89.6) for polyps ≥6 mm and ≥10 mm, respectively. CONCLUSION: Radiographers with training in CT colonographic evaluation achieved sensitivity and specificity in polyp detection comparable with that of experienced radiologists. MAIN MESSAGES: • The diagnostic accuracy of trained radiographers was comparable to that of experienced radiologists. • The use of radiographers in reading CTC examinations is acceptable, however radiologists would still be necessary for the evaluation of extracolonic findings. • Skilled non-radiologists may play a vital role as a second reader of intraluminal findings or by performing quality control of examinations before patient dismissal

Greater body mass index is a better predictor of subclinical cardiac damage at long-term follow-up in men than is insulin sensitivity:a prospective, population-based cohort study

To examine whether lower insulin sensitivity as determined by homeostatic model assessment (HOMA-%S) was associated with increased left ventricular mass (LVM) and presence of LV diastolic dysfunction at long-term follow-up, independently of body mass index (BMI), in middle-aged, otherwise healthy males

Which Tumor Suppressor Gene Plays an Important Role in Oncogenesis of Oral Cancer?

口腔領域癌の遺伝子学的解析はあまり行われていないため, 本稿では当科における癌抑制遺伝子異常の検索結果を用いて, 口腔癌においてどの遺伝子が重要な役割を果たしているのかを検討した。試料は, 口腔扁平上皮癌組織と, 同一症例の正常組織を用いた。RB遺伝子とWT遺伝子についてはサザンブロッティング法により, また, APC, P53, VHL, p15, p16, p18遺伝子についてはPCR-SSCP法および塩基配列決定法を用いて検索した。さらに, APC遺伝子についてはエクソン11のポリモルフィズムを利用したPCR-LOH分析をあわせて行った。以下に示す結果を得た。(1)APC遺伝子の点突然変異は8.3%, APC-LOHは informative 症例中の72.7%に認められた。(2)p16遺伝子とp18遺伝子の点突然変異はそれぞれ4.0%, 3.8%に認められた。p15遺伝子異常は認められなかった。(3)p53心遺伝子異常は7.7%に認められた。(4)WT遺伝子の部分欠失を6.5%に認めた。(5)RB遺伝子とVHL遺伝子の異常は認められなかった。以上の結果から, 種々の癌抑制遺伝子のうち, 特にAPC遺伝子が口腔扁平上皮癌発生に重要な役割を果たしていることが示唆された。Since there are few molecular biological studies on oral cancer, we evaluated genes which would play an important role in the oncogenesis of oral cancer based on our previous studies. To elucidate whether or not abnormalities of RB and WT genes could contribute to the development of oral squamous-cell carcinoma (SCC), genomic DNAs obtained from tumors and corresponding normal tissues were examined with Southern blotting. On the other hand, PCR-SSCP (polymerase chain reaction single-strand conformation polymorphism) and sequence analyses were performed to detect possible mutations of APC, VHL, p15, p16, p18 and p53. We also examined the tissue samples to detect loss of heterozygosity (LOH) at exon 11 of APC gene by PCR-LOH assay. We obtained the following results: (1) Point mutations of APC gene in tumor tissues were identified in 8.3(nil)atients with oral SCC, and PCR-LOH assay revealed LOH at exon 11 of APC gene in 72.71024720030f informative cases. (2) Point mutations of p16 and p18 genes were detected in 4.0-0x1.db55b085084p-148nd 3.80f oral SCC patients, respectively. However, no mutation of p15 gene was found. (3) Abnormalities of p53 gene were detected in 7.726725462457f all cases. (4) Southern blotting revealed partial deletions and rearrangements of WT gene in 6.50f the cases. (5) No abnormality of VHL and RB genes was detected in any of the cases. These results suggest that APC gene is most significantly associated with the development of human oral SCC among the known tumor suppressor genes

Common carotid segmentation in 18F-sodium fluoride PET/CT scans: Head-to-head comparison of artificial intelligence-based and manual method

Background: Carotid atherosclerosis is a major cause of stroke, traditionally diagnosed late. Positron emission tomography/computed tomography (PET/CT) with 18F-sodium fluoride (NaF) detects arterial wall micro-calcification long before macro-calcification becomes detectable by ultrasound, CT or magnetic resonance imaging. However, manual PET/CT processing is time-consuming and requires experience. We compared a convolutional neural network (CNN) approach with manual segmentation of the common carotids. Methods: Segmentation in NaF-PET/CT scans of 29 healthy volunteers and 20 angina pectoris patients were compared for segmented volume (Vol) and mean, maximal, and total standardized uptake values (SUVmean, SUVmax, and\ua0SUVtotal). SUVmean was the average of SUVmeans within the VOI, SUVmax the highest SUV in all voxels in the VOI, and SUVtotal the SUVmean multiplied by the Vol of the VOI. Intra\ua0and Interobserver variability with manual segmentation was examined in 25 randomly selected scans. Results: Bias for Vol, SUVmean, SUVmax, and SUVtotal were 1.33 \ub1 2.06, −0.01 \ub1 0.05, 0.09 \ub1 0.48, and 1.18 \ub1 1.99 in the left and 1.89 \ub1 1.5, −0.07 \ub1 0.12, 0.05 \ub1 0.47, and 1.61 \ub1 1.47, respectively, in the right common carotid artery. Manual segmentation lasted typically 20 min versus 1 min with the CNN-based approach. Mean Vol deviation at repeat manual segmentation was 14% and 27% in left and right common carotids. Conclusions: CNN-based segmentation was much faster and provided SUVmean values virtually identical to manually obtained ones, suggesting CNN-based analysis as a promising substitute of slow and cumbersome manual processing