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Background: There is limited evidence regarding the application of [18F] fluorodeoxyglucose (FDG)-PET/MRI in patients with a suspected clinical recurrence, who underwent liver transplantation for hepatocellular carcinoma (HCC). Therefore, we compared the accuracy of PET/MR and standard-of-care (SOC) imaging in these patients., Methods: We retrospectively reviewed 26 patients, whose liver were transplanted for HCC and were suspected of disease relapse based on biochemical analysis or SOC follow-up imaging, and carried out PET/MRI with diffusion-weighted imaging sequences on them. All patients underwent SOC imaging within the 2 months prior to the PET/MRI examination and had follow-up data for at least 12 months after. Reference standards were histopathology, clinical and imaging follow-up data., Results: Sensitivity, specificity, positive predictive value, negative predictive value and accuracy for PET/MRI were 100, 94, 91, 100 and 96%, whereas for SOC imaging were 80, 69, 61, 85 and 73%. The accuracy of PET/MRI was higher with respect to SOC imaging, although not significantly., Conclusions: PET/MRI is useful for oncological surveillance of patients who have undergone liver transplantation for HCC, particularly in cases of allergy to contrast media, renal failure or persistently elevated alpha-fetoprotein levels, and with no identification of metastatic/relapsing foci at standard-of-care imaging., (Copyright © 2022 Wolters Kluwer Health, Inc. All rights reserved.)

Purpose: A morphofunctional approach to the management of brain tumours has been claimed to increase diagnostic accuracy. Among the proposed single-photon emission tomography (SPET) tracers, (99m)Tc-sestamibi is able to distinguish recurrent tumour from radio-necrosis and to identify early response or resistance to chemotherapy. Major drawbacks of sestamibi, that is, poor morphological resolution and the sites of physiological uptake, could be overcome by dual-modality, integrated systems. The purpose of this study was to investigate the real usefulness of (99m)Tc-sestamibi SPET/computed tomography (CT) and to establish a semiquantitative index., Methods: Charts from 33 consecutive patients selected for surgery, who underwent preoperative SPET/CT and magnetic resonance imaging (MRI), were reviewed. Tumours were confirmed histologically after the surgery in all patients and classified according to WHO recommendations. Semiquantitative indexes were obtained on images (maximum likelihood expectation maximization reconstructed) with and without attenuation correction and visual analysis of SPET versus SPET/CT was performed., Results: A significant statistical difference was shown between SPET and SPET/CT in terms of the delineation of medial shift, oedema and the ability to distinguish tumour from the skull-meninges complex and plexus. With regard to semiquantitative indexes, a ratio obtained comparing counts/pixel derived from a region of interest in the tumour area with mirrored region of interest in the contralateral site revealed a sensitivity of 90.9% and specificity of 71.45% in discriminating WHO grade 4 gliomas from a lower grade., Conclusion: SPET/CT can distinguish tumour from the skull and other sites of physiological uptake better than SPET alone (as confirmed by MRI in all cases) and affords a morphological map. The proposed semiquantitative index also seems promising in identifying higher-grade disease. SPET/CT thus seems a useful additional tool in brain tumour management, especially when MRI is not feasible or PET/CT is not available.

Aim: To establish a standardized non-invasive imaging protocol for patients with pheochromocytoma undergoing surgery., Methods: A series of 32 consecutive patients (16 men, 16 women; median age 43 years, range 15-71 years) with biochemically confirmed pheochromocytoma underwent computed tomography (CT) scanning, magnetic resonance imaging (MRI) and meta-[I]iodobenzylguanidine (MIBG) whole-body scintigraphy prior to adrenalectomy or excision of extra-adrenal tumour (paraganglioma)., Results: At final pathology no malignant pheochromocytomas were found. The tumour was right-sided in 16 (50%) patients, left-sided in 13 (41%), extra-adrenal (sympathetic ganglia, upper abdomen) in two (6%) and bilateral in one (3%) patient. Overall, the median greatest diameter (size) of the tumour was 35 mm (range, 15-90 mm). The sensitivity of CT, MRI and MIBG scintigraphy was 90%, 93% and 91%, and the specificity was 93%, 93% and 100%, respectively. The three patients with false negative scintigraphy had an intra-adrenal tumour, ranging from 20 to 50 mm in size. The presence of necrosis within the mass might justify the lack of significant uptake of radiopharmaceutical in two patients, and the small size (15 mm) of the mass in the other. There were two false positive results with both CT and MRI, and no false positive MIBG scintigraphy, which had the highest (100%) positive predictive value. The combination of MRI+MIBG scintigraphy reached 100% sensitivity and positive predictive value., Conclusion: Our data suggest that this imaging protocol should be used in all patients with biochemically confirmed pheochromocytoma.

Objective: The objective of this work was to evaluate any variation of renal function detected by renal scintigraphy after the suprarenal fixation of endografts for abdominal aortic aneurysm (AAA) repair., Summary Background Data: In the few articles that have considered this problem, renal function was evaluated only by biochemical tests, which are inadequate in demonstrating small changes in renal function and in appreciating the worsening of a single kidney's function., Methods: Between April 1999 and May 2002, 47 patients with an inappropriate infrarenal proximal neck had a suprarenal fixation for AAA. To assess renal function, a technetium-99m diethylene triamine penta-acetic acid (TC-DTPA) perfusion scintigraphy was performed preoperatively on the third postoperative day and at 6, 12 months, and then yearly thereafter. Worsening of renal function was defined as a decrease of glomerular filtration rate (GFR) > or =20% (detected with Gates method). Serum creatinine level was tested preoperatively and at the first and third postoperative day., Results: Endograft deployment was technically successful in 44 patients (93.6%); clinical perioperative success was obtained in 46 patients (97.8%). In 12 patients (25.5%), a permanent reduction of the GFR was observed using postoperative TC-DTPA perfusion scintigraphy. By 99m TC-DTPA perfusion scintigraphy, a permanent reduction of GFR was observed postoperatively in 12 patients. A slight GFR reduction (<20%) was present in 7 (14.9%) patients, due to the planned occlusion of accessory renal arteries. A more significant GFR reduction (>20%) was present unexpectedly in 5 (10.6%) patients, in 3 of these a single kidney was involved, in 5 both with an increase of the serum creatinine level >20%., Conclusions: Suprarenal fixation of endografts in AAA treatment is a safe procedure with good early and midterm procedural results and a risk of GFR impairment (>20%) of 10.6%.