Audiovisual intervention alleviates anxiety of patients during PET/CT imaging.

AIM: to assess if the use of an audiovisual intervention in the uptake room and/or in the scanning room, could help to reduce anxiety during [18F]FDG PET/CT imaging. METHODS: We prospectively studied 120 patients referred for [18F]FDG PET/CT imaging. Patients were allocated in 4 groups of 30 patients depending on the use of the audiovisual intervention: (1) no audiovisual intervention; (2) audiovisual intervention only in the uptake room; (3) audiovisual intervention only in the scanning room; (4) audiovisual intervention in the uptake and the scanning rooms. In order to measure the anxiety levels of the patients before and after the scan, all patients answered the State-Trait Anxiety Inventory (STAI). RESULTS: The anxiety status across typical situations on a daily basis (STAI-T) of the 4 groups of patients was comparable with no significant differences. The mean State Anxiety (STAI-S) sum-score at prescan and postscan among groups was: (1) 17.5±8.7 vs. 17.3±8.6, p=0.834; (2) 17.4±10.5 vs. 15.8±9.6, p=0.110; (3) 17.5±11.7 vs. 15.1±9.8, p= 0.013; (4) 17.4±9.7 vs. 14.9±8.1, p= 0.009. The percentage of patients with reduction of the STAI-S score among groups 1-4 was 17%, 47%, 50%, and 66%, respectively. The variation of the percentage of patients with lower scores after intervention among groups was statistically significant (p<0.001). CONCLUSION: Audiovisual intervention decreases anxiety levels of patients referred for PET/CT imaging. The results of our study support a beneficial effect of the audiovisual intervention and its potential to alleviate the anxiety of oncological patients who undergo a PET/CT scan.

Brain metabolic changes in patients with disseminated malignant melanoma under immunotherapy.

Although there is evidence that chemotherapy can have side effects on metabolism and brain function, there are few studies on the occurrence of these side effects with immunotherapy. The present study was conducted to assess whether brain metabolic changes occur in patients with malignant melanoma under immunotherapy. Thirty-nine patients after surgical intervention and with a diagnosis of malignant melanoma were retrospectively included and were divided into two groups: one group under the first-line therapy with anti-programmed cell death-1 ± anti-cytotoxic T lymphocyte antigen-4 monoclonal antibodies and the other group without any treatment after surgery, which served as a control. Basal and follow-up whole body and brain 2-[ 18 F]fluoro-2-deoxy-D-glucose ( 18 F]FDG) PET/computed tomography (CT) studies were performed. Changes in brain glucose metabolism after treatment initiation of the immunotherapy group were compared with the findings in the control group. In addition, longitudinal regression analysis to investigate whether the time under immunotherapy influenced the changes of brain metabolism was performed. None of the patients presented cognitive impairment or other neurological alterations between basal and follow-up brain [ 18 F]FDG PET/CT examinations. The statistical analysis revealed a significant relative SUV (SUVr)-loss in the left frontal region in patients of the immunotherapy group compared with the control group, with radjusted = -0.62 and P = 0.008. Severity of SUVr-loss was correlated with duration of treatment. Patients with disseminated malignant melanoma receiving immunotherapy may present a decrease of brain metabolism in the left frontal region, which is related with time-under-treatment, without any clinical evidence of neurological disorder.

Digital versus analog PET/CT in patients with known or suspected liver metastases.

AIM: To assess if digital PET/CT improves liver lesion detectability compared to analog PET/CT in patients with known or suspected liver metastases. MATERIALS AND METHODS: We prospectively included 83 cancer patients, with one or more of these conditions: history of liver metastases, clinical risk of having liver metastases or presence of suspected liver metastases on the first of the two PET/CTs. All patients were consecutively scanned on each PET/CT on the same day after a single [18F]fluorodeoxyglucose dose injection. The order of acquisition was randomly assigned. Three nuclear medicine physicians assessed both PET/CTs by counting the foci of high uptake suspicious of liver metastases. Findings were correlated with appropriate reference standards; 19 patients were excluded from the analysis due to insufficient lesion nature confirmation. The final sample consisted of 64 patients (34 women, mean age 68 ± 12 years). RESULTS: As per-patient analysis, the mean number of liver lesions detected by the digital PET/CT (3.84 ± 4.25) was significantly higher than that detected by the analog PET/CT (2.91 ± 3.31); P < 0.001. Fifty-five patients had a positive PET/CT study for liver lesions. In 26/55 patients (47%), the digital PET/CT detected more lesions; 7/26 patients (27%) had detectable lesions only by the digital system and had <10 mm of diameter. Twenty-nine patients had the same number of liver lesions detected by both systems. In nine patients both PET/CT systems were negative for liver lesions. CONCLUSION: Digital PET/CT offers improved detectability of liver lesions over the analog PET/CT in patients with known or suspected liver metastases.

Correction to: Superior performance of 18F-fluorocholine digital PET/CT in the detection of parathyroid adenomas.

The correct administered activity of 18F-FCH is 0.1-0.14 mCi/Kg, which is equivalent to 3.7-5.2 MBq/kg.

Superior performance of 18F-fluorocholine digital PET/CT in the detection of parathyroid adenomas.

OBJECTIVE: To compare detectability of hyperfunctioning parathyroid tissue (HPT) by digital and analog 18F-fluorocholine PET/CT in patients with primary hyperparathyroidism and negative/inconclusive 99mTc-MIBI scintigraphy-SPECT/CT. MATERIALS AND METHODS: Thirty-three patients with primary hyperparathyroidism and negative/inconclusive 99mTc-MIBI scintigraphy-SPECT/CT were prospectively included. All patients accepted to be scanned by digital and analog PET/CT in the same imaging session after a single injection of 18F-fluorocholine. Three nuclear medicine physicians evaluated the digital and analog PET/CT datasets to assess the detection rate of HPT. Maximum standard uptake values (SUVmax) of HPT and locoregional lymph nodes were measured in both systems. RESULTS: HPT was detected in 30/33 patients by the digital system, whereas it was detected in 22/33 patients by the analog system (p < 0.01). Moreover, in 21 of these 33 patients, both systems detected one focal 18F-fluorocholine uptake, and in one patient the digital system detected two foci. Histopathology demonstrated HPT in 32 patients and it was inconclusive in one patient. The digital PET/CT detected HPT in 29 of the 32 patients, and the analog system in 22 of the 32 (p < 0.01). All HPT suspected lesions resected and detected only by the digital system (n = 8) were < 10 mm (7.5 ± 1.3 mm), while those detected by both systems (n = 22) were > 10 mm (13 ± 3.8 mm). SUVmax of HPT lesions was significantly higher than SUVmax of locoregional lymph node independently of the PET/CT system used (4.5 ± 1.9 vs. 2.9 ± 1.3, p < 0.0001). CONCLUSIONS: Digital PET/CT offers superior performance over analog system in patients with suspected HPT and previous negative/inconclusive imaging examinations, particularly in sub-centimeter lesions. SUVmax can help in the differentiation between HTP and locoregional lymph nodes.

Comparison of image quality and lesion detection between digital and analog PET/CT.

OBJECTIVE: The purpose of this study was to compare image quality and lesion detection capability between a digital and an analog PET/CT system in oncological patients. MATERIALS AND METHODS: One hundred oncological patients (62 men, 38 women; mean age of 65 ± 12 years) were prospectively included from January-June 2018. All patients, who accepted to be scanned by two systems, consecutively underwent a single day, dual imaging protocol (digital and analog PET/CT). Three nuclear medicine physicians evaluated image quality using a 4-point scale (-1, poor; 0, fair; 1, good; 2, excellent) and detection capability by counting the number of lesions with increased radiotracer uptake. Differences were considered significant for a p value <0.05. RESULTS: Improved image quality in the digital over the analog system was observed in 54% of the patients (p = 0.05, 95% CI, 44.2-63.5). The percentage of interrater concordance in lesion detection capability between the digital and analog systems was 97%, with an interrater measure agreement of κ = 0.901 (p < 0.0001). Although there was no significant difference in the total number of lesions detected by the two systems (digital: 5.03 ± 10.6 vs. analog: 4.53 ± 10.29; p = 0.7), the digital system detected more lesions in 22 of 83 of PET+ patients (26.5%) (p = 0.05, 95% CI, 17.9-36.7). In these 22 patients, all lesions detected by the digital PET/CT (and not by the analog PET/CT) were < 10 mm. CONCLUSION: Digital PET/CT offers improved image quality and lesion detection capability over the analog PET/CT in oncological patients, and even better for sub-centimeter lesions.