Prognostic value of echocardiographically assessed right ventricular dysfunction in patients with pulmonary embolism

Background: Echocardiographically assessed right ventricular dysfunction is increasingly used to guide more aggressive therapy in hemodynamically stable patients with acute pulmonary embolism (PE). However, the prognostic value of right ventricular dysfunction in these patients is still unclear. Methods: We systemically reviewed the literature to assess the prevalence of echocardiographic right ventricular dysfunction and the association with adverse outcomes in patients with PE who had this condition. The methodologic quality of each study was scored. Absolute risks of the outcome events were calculated for each study separately, and positive predictive values of PE-related mortality were determined for normotensive patients. Results: Seven studies were included. All had methodologic shortcomings, but they suggested an at least 2-fold increased risk of PE-related mortality in patients with right ventricular dysfunction, the prevalence of which varied from 40% to 70%. However, this seems to be less convincing in hemodynamically stable patients. The only 2 studies that allowed for an estimation of the accuracy in normotensive patients showed low positive predictive values of echo cardiographic right ventricular dysfunction for PE-related in-hospital mortality (positive predictive value, 4% and 5% in the 2 studies). Conclusion: It remains unclear whether echocardiographic right ventricular dysfunction is a prevalent and reliable predictor of adverse outcomes in hemodynamically stable patients with acute P

Lymphoscintigraphy and SPECT/CT using 99mTc filtered sulphur colloid in chylothorax.

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Deep Learning Denoising Improves and Homogenizes Patient [¹⁸F]FDG PET Image Quality in Digital PET/CT

Given the constant pressure to increase patient throughput while respecting radiation protection, global body PET image quality (IQ) is not satisfactory in all patients. We first studied the association between IQ and other variables, in particular body habitus, on a digital PET/CT. Second, to improve and homogenize IQ, we evaluated a deep learning PET denoising solution (Subtle PETTM) using convolutional neural networks. We analysed retrospectively in 113 patients visual IQ (by a 5-point Likert score in two readers) and semi-quantitative IQ (by the coefficient of variation in the liver, CVliv) as well as lesion detection and quantification in native and denoised PET. In native PET, visual and semi-quantitative IQ were lower in patients with larger body habitus (p p ≤ 0.03 for CVliv). After PET denoising, visual IQ scores increased and became more homogeneous between patients (4.8 ± 0.3 in denoised vs. 3.6 ± 0.6 in native PET; p liv were lower in denoised PET than in native PET, 6.9 ± 0.9% vs. 12.2 ± 1.6%; p liv according to weight was significantly lower in denoised than in native PET (p = 0.0002), demonstrating more uniform CVliv. Lesion concordance rate between both PET series was 369/371 (99.5%), with two lesions exclusively detected in native PET. SUVmax and SUVpeak of up to the five most intense native PET lesions per patient were lower in denoised PET (p TM allowed [18F]FDG PET global image quality to be improved and homogenized, while maintaining satisfactory lesion detection and quantification. DL-based denoising may render body habitus adaptive PET protocols unnecessary, and pave the way for the improvement and homogenization of PET modalities

Stimulated thyroglobulin level at ablation in differentiated thyroid cancer: the impact of treatment preparation modalities and tumor burden

International audienc

Artificial intelligence-based PET denoising could allow a two-fold reduction in [18F]FDG PET acquisition time in digital PET/CT

CERVOXYInternational audiencePurpose We investigated whether artificial intelligence (AI)-based denoising halves PET acquisition time in digital PET/CT. Methods One hundred ninety-five patients referred for [ 18 F]FDG PET/CT were prospectively included. Body PET acquisitions were performed in list mode. Original "PET90" (90 s/bed position) was compared to reconstructed ½-duration PET (45 s/bed position) with and without AI-denoising, "PET45AI and PET45". Denoising was performed by SubtlePET™ using deep convolutional neural networks. Visual global image quality (IQ) 3-point scores and lesion detectability were evaluated. Lesion maximal and peak standardized uptake values using lean body mass (SUL max and SUL peak), metabolic volumes (MV), and liver SUL mean were measured, including both standard and EARL 1 (European Association of Nuclear Medicine Research Ltd) compliant SUL. Lesion-to-liver SUL ratios (LLR) and liver coefficients of variation (CV liv) were calculated. Results PET45 showed mediocre IQ (scored poor in 8% and moderate in 68%) and lesion concordance rate with PET90 (88.7%). In PET45AI, IQ scores were similar to PET90 (P = 0.80), good in 92% and moderate in 8% for both. The lesion concordance rate between PET90 and PET45AI was 836/856 (97.7%), with 7 lesions (0.8%) only detected in PET90 and 13 (1.5%) exclusively in PET45AI. Lesion EARL 1 SUL peak was not significantly different between both PET (P = 0.09). Lesion standard SUL peak , standard and EARL1 SUL max , LLR and CV liv were lower in PET45AI than in PET90 (P < 0.0001), while lesion MV and liver SUL mean were higher (P < 0.0001). Good to excellent intraclass correlation coefficients (ICC) between PET90 and PET45AI were observed for lesion SUL and MV (ICC ≥ 0.97) and for liver SUL mean (ICC ≥ 0.87). Conclusion AI allows [ 18 F]FDG PET duration in digital PET/CT to be halved, while restoring degraded ½-duration PET image quality. Future multicentric studies, including other PET radiopharmaceuticals, are warranted

Diarree en koorts bij chemotherapie door listeriose

We present two patients with colorectal carcinoma who were admitted with fever and diarrhoea during treatment with chemotherapy. Blood cultures taken from both patients revealed an infection with Listeria monocytogenes. A contaminated ice cream was probably the source of infection in one patient. The other patient died of the listeriosis. Patients with diminished cellular immunity are at risk of invasive listeriosis. Listeriosis has a high mortality rate in this group of patients. Intravenous penicillin or ampicillin for 4 to 6 weeks is the first choice of antibiotic treatment. These antibiotics can be combined with an aminoglycoside or trimethoprim-sulfamethoxazole for a synergistic effect. To prevent invasive listeriosis we recommend strict dietary advice to all patients with diminished cellular immunit

Harmonizing FDG PET quantification while maintaining optimal lesion detection: prospective multicentre validation in 517 oncology patients.

International audiencePoint-spread function (PSF) or PSF + time-of-flight (TOF) reconstruction may improve lesion detection in oncologic PET, but can alter quantitation resulting in variable standardized uptake values (SUVs) between different PET systems. This study aims to validate a proprietary software tool (EQ.PET) to harmonize SUVs across different PET systems independent of the reconstruction algorithm used. NEMA NU2 phantom data were used to calculate the appropriate filter for each PSF or PSF+TOF reconstruction from three different PET systems, in order to obtain EANM compliant recovery coefficients. PET data from 517 oncology patients were reconstructed with a PSF or PSF+TOF reconstruction for optimal tumour detection and an ordered subset expectation maximization (OSEM3D) reconstruction known to fulfil EANM guidelines. Post-reconstruction, the proprietary filter was applied to the PSF or PSF+TOF data (PSFEQ or PSF+TOFEQ). SUVs for PSF or PSF+TOF and PSFEQ or PSF+TOFEQ were compared to SUVs for the OSEM3D reconstruction. The impact of potential confounders on the EQ.PET methodology including lesion and patient characteristics was studied, as was the adherence to imaging guidelines. For the 1380 tumour lesions studied, Bland-Altman analysis showed a mean ratio between PSF or PSF+TOF and OSEM3D of 1.46 (95%CI: 0.86-2.06) and 1.23 (95%CI: 0.95-1.51) for SUVmax and SUVpeak, respectively. Application of the proprietary filter improved these ratios to 1.02 (95%CI: 0.88-1.16) and 1.04 (95%CI: 0.92-1.17) for SUVmax and SUVpeak, respectively. The influence of the different confounding factors studied (lesion size, location, radial offset and patient's BMI) was less than 5%. Adherence to the European Association of Nuclear Medicine (EANM) guidelines for tumour imaging was good. These data indicate that it is not necessary to sacrifice the superior lesion detection and image quality achieved by newer reconstruction techniques in the quest for harmonizing quantitative comparability between PET systems

F18-choline PET/CT guided surgery in primary hyperparathyroidism when ultrasound and MIBI SPECT/CT are negative or inconclusive: the APACH1 study

International audiencePURPOSE:To evaluate the sensitivity of F18-choline (FCH) PET/CT for parathyroid adenoma detection prior to surgery in patients with primary hyperparathyroidism and negative or inconclusive cervical ultrasound and Tc99m-sestaMIBI SPECT/CT.METHODS:We conducted a prospective bicentric study (NCT02432599). All patients underwent FCH PET/CT. The result was scored positive, inconclusive or negative. The number of uptakes and their sites were recorded. The FCH PET/CT result guided the surgical procedure (minimally invasive parathyroidectomy, bilateral cervical exploration, or other in case of multiple or ectopic foci). FCH PET/CT results were compared to the surgical and pathological findings and the follow-up.RESULTS:Twenty-five patients were included. Mean calcium and PTH levels prior to surgery were 2.76 ± 0.17 mmol/l and 94.8 ± 37.4 ng/l. Nineteen (76%) FCH PET/CTs were scored positive, 3 (12%) inconclusive and 3 (12%) negative, showing 21 cases of uniglandular disease, including 1 ectopic localization and 1 case of multiglandular (3 foci) disease. Mean lesion size was 13.1 ± 8.6 mm. Twenty-four patients underwent surgery. FCH PET/CT guided surgery in 22 (88%) patients, allowing for 17 minimally invasive parathyroidectomies, 1 bilateral cervical exploration for multifocality and 4 other surgical procedures. Two patients with negative FCH-PET/CT underwent bilateral cervical exploration. When dichotomizing the FCH PET/CT results, thereby classifying the inconclusive FCH PET/CT results as positive, the per lesion and per patient sensitivities were 91.3% (95%CI: 72.0-98.9) and 90.5% (95%CI: 69.6-98.8) and the corresponding positive predictive values were 87.5% (95%CI: 67.6-97.3) and 86.4% (95%CI: 65.1-97.1), respectively. Twenty-one (88%) patients were considered cured after surgery. Their mean calcium level after surgery was 2.36 ± 0.17 mmol/l.CONCLUSIONS:Preoperative FCH PET/CT has a high sensitivity and positive predictive value for parathyroid adenoma detection in patients with primary hyperparathyroidism and negative or inconclusive conventional imaging results. Bilateral cervical exploration could be avoided in the majority (75%) of patients