Use of computed tomography assessed kidney length to predict split renal GFR in living kidney donors.

OBJECTIVES: Screening of living kidney donors may require scintigraphy to split glomerular filtration rate (GFR). To determine the usefulness of computed tomography (CT) to split GFR, we compared scintigraphy-split GFR to CT-split GFR. We evaluated CT-split GFR as a screening test to detect scintigraphy-split GFR lower than 40 mL/min/1.73 m2/kidney. METHODS: This was a monocentric retrospective study on 346 potential living donors who had GFR measurement, renal scintigraphy, and CT. We predicted GFR for each kidney by splitting GFR using the following formula: Volume-split GFR for a given kidney = measured GFR*[volume of this kidney/(volume of this kidney + volume of the opposite kidney)]. The same formula was used for length-split GFR. We compared length- and volume-split GFR to scintigraphy-split GFR at donation and with a 4-year follow-up. RESULTS: A better correlation was observed between length-split GFR and scintigraphy-split GFR (r = 0.92) than between volume-split GFR and scintigraphy-split GFR (r = 0.89). A length-split GFR threshold of 45 mL/min/1.73 m2/kidney had a sensitivity of 100 % and a specificity of 75 % to detect scintigraphy-split GFR less than 40 mL/min/1.73 m2/kidney. Both techniques with their respective thresholds detected living donors with similar eGFR evolution during follow-up. CONCLUSION: Length-split GFR can be used to detect patients requiring scintigraphy. KEY POINTS: • Excellent correlation between kidney length and scintigraphy predicted GFR • Kidney length screening detects all donors with GFR lower than 40 mL/min/1.73 m 2 • Kidney length screening can replace scintigraphy screening.

Validation of early image acquisitions following Tc-99 m sestamibi injection using a semiconductors camera of cadmium-zinc-telluride.

BACKGROUND: Cadmium-zinc-telluride (CZT) cameras allow to decrease significantly the acquisition time of myocardial perfusion imaging (MPI), but the duration of the examination is still long. Therefore, this study was performed to test the feasibility of early imaging following injection of Tc-99 m sestamibi using a CZT camera. METHODS: Seventy patients underwent both an early and a delayed image acquisition after exercise stress test (n = 30), dipyridamole stress test (n = 20), and at rest (n = 20). After injection of Tc-99 m sestamibi, the early image acquisition started on average within 5 minutes for the exercise and rest groups, and 3 minutes 30 seconds for the dipyridamole group. Two independent observers evaluated image quality and extracardiac uptake on four-point scales. The difference between early and later images for each patient was scored on a five-point scale. RESULTS: The image quality and extracardiac uptake of early and delayed image acquisitions were not different for the three groups (P > .05). There was no significant difference between early and delayed image acquisitions in the exercise, dipyridamole, and rest groups, respectively, in 63%, 40%, and 80% of cases. In the exercise group and rest group, a defect was only present in early MPI, respectively, in 13% and 20% of cases. A defect was only present in delayed images in 10% of cases in the exercise group and in 45% of cases in the dipyridamole group. CONCLUSIONS: There was no difference between early and later image acquisitions in terms of quality. This protocol reduces the length of the procedure for the patient. Beginning with early image acquisitions may help to overcome the artifacts that are observed at the delayed time.

Performance of FDG PET/CT at initial diagnosis in a rare lymphoma: nodular lymphocyte-predominant Hodgkin lymphoma.

PURPOSE: Nodular lymphocyte-predominant Hodgkin lymphoma (NLPHL) is a rare Hodgkin lymphoma distinguished from classical Hodgkin lymphoma (cHL) by the nature of the neoplastic cells which express B-cell markers. We wanted to determine the diagnostic performance of FDG PET/CT in initial assessment and its therapeutic impact on staging. METHODS: We retrospectively studied a population of 35 patients with NLPHL (8 previously treated for NLHPL, 27 untreated). All patients underwent an initial staging by pretherapeutic FDG PET/CT. The impact on initial stage or relapse stage was assessed by an independent physician. RESULTS: In a per-patient analysis, the sensitivity of the pretherapeutic FDG PET/CT was 100%. In a per-site analysis, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy of pretherapeutic FDG PET/CT were 100%, 99%, 97%, 100% and 99%, respectively. Pretherapeutic FDG PET/CT led to a change in the initial stage/relapse stage in 12 of the 35 patients (34%). In contrast to previous results established without FDG PET/CT, 20% of patient had osteomedullary lesions. CONCLUSION: Pretherapeutic FDG PET/CT has excellent performance for initial staging or relapse staging of NLPHL.

Clinical value of a high-fat and low-carbohydrate diet before FDG-PET/CT for evaluation of patients with suspected cardiac sarcoidosis.

BACKGROUND: We hypothesized that a high-fat and low-carbohydrate (HFLC) diet before FDG-PET/CT could identify patients with active cardiac sarcoidosis (CS). METHODS: Fifty-eight sarcoidosis patients with a suspicion of CS consumed a HFLC diet before FDG-PET/CT. Clinical, electrical, and other imaging investigations were compared to PET results. RESULTS: Using Japanese Ministry of Health and Welfare (JMHW) criteria as a gold standard, 21% (12/58) of patients had a CS. Sensitivity and specificity of PET (visual analysis) were 83% (10/12) and 78% (36/46), respectively, with a very good interobserver agreement (k = 0.86). 70% (7/10) of the patients with a positive PET and negative JMHW criteria exhibited abnormalities suggestive of CS either on MR (n = 3) or SPECT (n = 4). Comparison with the presence of delayed enhancement on magnetic resonance imaging helped to classify patients with active (PET positive) or non-active CS (PET negative). In addition, when MR and PET were both negative, none of the patients met the JMHW criteria. PET response under treatment was concordant with clinical evolution in 11/13 patients. CONCLUSIONS: FDG-PET/CT after HFLC diet is a sensitive tool for the diagnosis of active CS. Combined use of PET and MR is promising for the detection and characterization of CS lesions.

Phase III Study of 18F-PSMA-1007 Versus 18F-Fluorocholine PET/CT for Localization of Prostate Cancer Biochemical Recurrence: A Prospective, Randomized, Crossover Multicenter Study.

The objective of this study was to compare 18F-PSMA-1007 PET/CT and 18F-fluorocholine PET/CT for the localization of prostate cancer (PCa) biochemical recurrence. Methods: This prospective, open-label, randomized, crossover multicenter study included PCa patients with prior definitive therapy and suspected PCa recurrence. All men underwent both 18F-PSMA-1007 PET/CT and 18F-fluorocholine PET/CT (102 received 18F-PSMA-1007 PET/CT first and 88 received 18F-fluorocholine PET/CT first). All images were assessed independently by 3 readers masked to all clinical information using a 3-point qualitative scale (0 = no recurrence, 1 = undetermined, and 2 = recurrence). Patients were monitored for approximately 6 mo. An independent panel with a urologist, radiologist, and nuclear physician reviewed all clinical data, including imaging and response to therapy, but were masked regarding PET/CT information; acting in consensus, they determined a patient-based and region-based composite standard of truth for PCa lesions. The "correct detection rates" for PCa lesions on a patient basis for each radiopharmaceutical were compared for the 3 readers individually and for the "average reader." Secondary objectives included determining whether PET/CT findings affected diagnostic thinking (impact of a test result on posttest vs. pretest probability of a correct diagnosis), therapeutic decision making (description and quantification of impact of diagnostic information gained with both radiopharmaceuticals on patient management), and adequacy of management changes. Results: A total of 190 patients were included. The primary endpoint was met. The overall correct detection rates were 0.82 for 18F-PSMA-1007 and 0.65 for 18F-fluorocholine (P < 0.0001) when undetermined findings were considered positive for malignancy and 0.77 and 0.57, respectively (P < 0.0001), when undetermined findings were considered negative for malignancy. A change in diagnostic thinking due to PET/CT was reported in 149 patients; 18F-PSMA-1007 contributed more than 18F-fluorocholine in 93 of these patients. In 122 patients, PET/CT led to an adequate diagnosis that benefited the patient; 18F-PSMA-1007 contributed more than 18F-fluorocholine in 88 of these patients. Conclusion: 18F-PSMA-1007 PET/CT is superior to 18F-fluorocholine PET/CT for the localization of PCa recurrence. Decision making was more beneficial when based on 18F-PSMA-1007 PET/CT results.

Comparison Between ESC and Duke Criteria for the Diagnosis of Prosthetic Valve Infective Endocarditis.

OBJECTIVES: The primary objective was to assess the value of the European Society of Cardiology (ESC) criteria, including 18F-fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG-PET/CT) in prosthetic valve infective endocarditis (PVE). Secondary objectives were: 1) to assess the reproducibility of 18F-FDG-PET/CT; 2) to compare its diagnostic value with that of echocardiography; and 3) to assess the diagnostic value of the presence of a diffuse splenic uptake BACKGROUND: 18F-FDG PET/CT has been added as a major criterion in the ESC 2015 infective endocarditis (IE) guidelines, but the benefit of the ESC criteria has not been prospectively compared with the conventional Duke criteria. METHODS: Between 2014 and 2017, 175 patients with suspected PVE were prospectively included in 3 French centers. After exclusion of patients with uninterpretable 18F-FDG PET/CT, 115 patients were evaluated, including 91 definite and 24 rejected IE, as defined by an expert consensus. RESULTS: Cardiac uptake by 18F-FDG PET/CT was observed in 67 of 91 patients with definite PVE and 6 with rejected IE (sensitivity 73.6% [95% confidence interval (CI): 63.3% to 82.3%], specificity 75% [95% CI: 53.3% to 90.2%]). The ESC 2015 classification increased the sensitivity of Duke criteria from 57.1% (95% CI: 46.3% to 67.5%) to 83.5% (95% CI: 74.3% to 90.5%) (p < 0.001), but decreased its specificity from 95.8% (95% CI: 78.9% to 99.9%) to 70.8% (95% CI: 48.9% to 87.4%). Intraobserver reproducibility of 18F-FDG PET/CT was good (kappa = 0.84) but interobserver reproducibility was less satisfactory (kappa = 0.63). A diffuse splenic uptake was observed in 24 (20.3%) patients, including 23 (25.3%) of definite PVE, and only 1 (4.2%) rejected PVE (p = 0.024). CONCLUSIONS: 18F-FDG PET/CT is a useful diagnostic tool in suspected PVE, and explains the greater sensitivity of ESC criteria than Duke criteria. However, 18F-FDG PET/CT also presents with important limitations concerning its feasibility, specificity, and reproducibility. Our study describes for the first time a new endocarditis criterion, that is, the presence of a diffuse splenic uptake on 18F-FDG PET/CT.

Bis-phosphonates-ultra small superparamagnetic iron oxide nanoparticles: a platform towards diagnosis and therapy.

A new type of multifunctional magnetic nano-platform for diagnosis and therapy applications was designed using bisphosphonate/carboxylic ligands.

Value of 18F-FDG PET/CT imaging in the staging, restaging, monitoring of response to therapy and surveillance of uterine leiomyosarcomas.

OBJECTIVE: Leiomyosarcoma (LMS) is the most common subtype of uterine sarcomas. It is a rare and aggressive tumour. The aim of the present study was to assess the performance of fluorine-18-fluorodeoxyglucose (F-FDG) PET/CT imaging in four clinical settings: initial staging, restaging, monitoring of response to therapy and post-therapy surveillance of uterine LMS. PATIENTS AND METHODS: A bicentric retrospective study was carried out on a group of 21 patients with uterine LMS for whom a total of 52 PET/CT scans were available in initial staging (n=11), restaging (n=11), monitoring of response to therapy (n=17) and post-therapy surveillance (n=13). Clinical (minimum 6 months after PET/CT scan) and/or imaging follow-up and pathology were used as the reference standard. RESULTS: In the initial staging, the sensitivity, specificity and accuracy of PET imaging were 80, 100 and 91%, respectively. In the restaging and monitoring of response to therapy, all these indices were 100%, whereas they were lower in post-therapy surveillance at 75, 100 and 85%, respectively, because of two false-negative results. False-negative lesions were an infracentimetric lung nodule in the initial staging and a peritoneal nodule that had increased in size between two PET/CT scans in post-therapy surveillance. PET-negative lesions were all identified on the computed tomography (CT) part of the PET/CT; thus, the performances of the exam improved to 100% on taking into account the CT component of the PET/CT. CONCLUSION: PET/CT imaging has a high diagnostic yield in the initial staging and restaging of uterine LMS, but seems less sensitive in post-therapy surveillance. Evaluation of the CT part improves the sensitivity of the PET scan. Thus, PET/CT imaging should be considered in patients presenting with LMS.

[The interest of 18FDG-PET in the management of testicular cancer]. / Apport de l'imagerie au 18FDG dans la prise en charge du cancer du testicule.

The key to prognosis. Initial staging and early recurrence diagnosis are key parameters in the treatment and outcome of testicular cancer. Initial staging. It is difficult using conventional modalities, which can miss node involvement and are non-specific since enlargement does not rhyme with involvement. 18FDG PET improves the accuracy of initial staging. Residual mass and recurrences. Existence of residual mass or enhancement of its Volume in the presence of an otherwise beneficial chemotherapy is difficult to manage. Several studies have demonstrated the value of 18FDG imaging in such cases. As for follow-up whole body 18FDG can prevent multiple diagnostic imaging and can diagnose recurrences with greater diagnostic accuracy than with other imaging modalities.

Functional imaging in extrapulmonary sarcoidosis: FDG-PET/CT and MR features.

Sarcoidosis is a multiorgan granulomatous disease of unknown etiology that primarily involves the lungs and the lymphatic system. Extrapulmonary sarcoidosis is common, occurring in 30 to 50% of patients. In this review, we describe and illustrate the role of F-FDG PET/CT and MR imaging in patients with extrapulmonary sarcoidosis. FDG-PET/CT and MR can improve the accuracy of the diagnosis of extrapulmonary involvement, specify the respective contributions of active and fibrotic components of lesions, guide the selection of the biopsy site, provide prognostic information, and guide therapeutic management. We focus on suggestive patterns that help to improve lesion characterization, especially when these lesions are clinically occult. In cardiac sarcoidosis, the combined use of FDG-PET/CT and cardiac MR may provide optimal detection of the disease by enabling the differentiation between patients with active granulomatous inflammation and those with fibrous lesions. In cases with central nervous system involvement, the T2 hypointensity of the dural and parenchymal lesions is helpful for identifying sarcoidosis. Granulomatous bone marrow infiltration in the axial skeleton can be sensitively detected by both FDG-PET/CT and MR. Muscular sarcoidosis can have a characteristic appearance with the "dark star" sign on MR and a thick linear FDG uptake that predominantly involves the lower legs, designated as the "tiger man" sign. Extrathoracic lymphadenopathy is commonly observed on FDG-PET/CT imaging; however, its features are not specific, and the differentiation of extrathoracic lymphadenopathy from metastatic disease, tuberculosis, or lymphoma may be difficult. Familiarity with the functional imaging features in extrapulmonary sarcoidosis in various anatomical locations plays a crucial role in the diagnosis and management of patients.

Contribution of multimodality imaging for positive and aetiological diagnosis of multiple brown tumours.

This report concerns a rare case of multiple brown tumours discovered in a setting of primary hyperparathyroidism in a 64-year-old patient presenting with weight loss and leg pain. Biological, radiological and pathological findings led to the diagnosis of brown tumours. The contribution of anatomic and nuclear imaging techniques to the diagnosis of brown tumours and their aetiological assessment as well as pre-surgery localisation of parathyroid adenomas in the context of primary hyperparathyroidism is discussed.

Diagnosis of synchronous isolated splenic metastasis from lung adenocarcinoma: complementary role of FDG PET/CT and diffusion-weighted MRI.

Isolated splenic metastasis is extremely rare. In this study, we report a case of a 52-year-old man referred for Pancoast Tobias Syndrome by which FDG PET/CT detected an isolated splenic metastasis. Diffusion-weighted MRI confirmed the isolated splenic lesion. A low apparent diffusion coefficient was consistent with a tumor lesion. CT-guided biopsy of both the lesions and histopathologic findings confirmed a lung adenocarcinoma with an isolated splenic metastasis. This case reveals a very rare occurrence of isolated splenic metastases in the context of lung cancer and illustrates the role of multimodality functional imaging for the early detection of uncommon metastasis.

Tracheobronchial FDG uptake in primary amyloidosis detected by PET/CT.

Tracheobronchial amyloidosis is a rare manifestation of the disease and has never been described with FDG PET/CT. In this study, we report a case of a 70-year-old man with increasing dyspnea, a right pleural effusion, a tracheobronchial circumferential wall thickening, and a mediastinal fat infiltration on CT scan. FDG PET/CT revealed intense tracheobronchial uptake associated with mediastinal and intra-abdominal fat uptake. Bronchoscopy and mediastinoscopy with biopsies confirmed the diagnosis of primary amyloidosis and excluded malignancy. FDG PET/CT could be useful for the evaluation of tracheobronchial amyloidosis metabolic activity and follow-up.

Visualization of amyloid arthropathy in light-chain systemic amyloidosis on F-18 FDG PET/CT scan.

We report a case of 63-year-old man with symmetrical joint swelling of the interphalangeal and metacarpal joints, associated with isolated hypogammaglobulinemia. Accessory glands biopsy revealed the presence of amyloidal deposits. PET/CT showed increased F-18 FDG activity in thickened soft tissues corresponding to amyloid arthropathy. Like multiple myeloma, PET/CT could be an interesting imaging in light-chain amyloidosis.

Clinical validation of simultaneous dual-isotope myocardial scintigraphy.

Simultaneous dual-isotope (rest thallium-201/stress technetium-99m sestamibi) myocardial single-photon emission tomography (SPET) would be an ideal procedure; however, (99m)Tc cross-talk on the (201)Tl window hampers its routine use. Photon energy recovery (PER) is a spectral deconvolution technique validated for scatter and cross-talk removal in phantom studies and a limited series of patients. In this study we aimed to validate the technique in 295 patients within a context of clinical routine practice. Conventional separate rest (201)Tl myocardial SPET data sets were visually compared with simultaneous dual-isotope data sets corrected by PER. Conventional separate rest (201)Tl data sets were identical to dual PER-corrected (201)Tl data sets in 173 (58.6%) patients. As dual PER (201)Tl data sets are corrected for (99m)Tc cross-talk but also for (201)Tl scatter, they were compared with separate rest (201)Tl data sets corrected by PER in the 122 discordant patients. No difference was found in 77 (26.1%) patients. In 26 (8.8%) patients, the difference consisted in the presence of a defect on dual PER (201)Tl data sets only, mirroring an ischaemic defect on (99m)Tc-sestamibi data sets. This difference can be attributed to the influence of stress on the kinetics of (201)Tl injected at rest. In the remaining 19 (6.4%) patients, the difference between separate and simultaneous PER-corrected data sets was scored as mild in 11 and moderate in eight patients and seemed to be related to multiple methodological factors. It is concluded that PER correctly removes (99m)Tc cross-talk. With the addition of an appropriate attenuation correction, the PER technique may allow the routine use of simultaneous dual-isotope myocardial scintigraphy in the near future.