Aim: Retrospective evaluation of the impact of integrated positron emission tomography/computed tomography (PET/CT) using ⁶⁸Ga-DOTA(0)-Phe(1)-Tyr(3)-octreotide (⁶⁸Ga-DOTATOC) on the therapeutic management of patients with neuroendocrine tumors (NET). Methods: The ⁶⁸Ga-DOTATOC-PET/CT data of 66 patients (31 male, 35 female; age: 29–79, mean age: 56 years) with known or suspected NET were included. Imaging data (PET and triple-phase contrast-enhanced CT) were evaluated in consensus by two readers for the visualization of NET manifestations. Combined PET/CT, clinical and imaging follow-up as well as histopathology (if available) served as the reference standard. In order to assess the impact of the respective submodalities on the therapeutic strategy chosen, the results were compared to the treatment decision made by the interdisciplinary NET tumor board of our institution. Results: Two of the initial 66 patients included did not suffer from NET according to further immunohistopathological examination. In 50 of the remaining 64 (78%) NET patients, a total of 181 NET manifestations were detected by PET/CT. 59/181 (32.6%) were detected by one submodality only (CT 17.1%, PET 15.5%, p for comparison of both = 0.459). Combined PET/CT reading had an impact on the therapeutic management in 24 of 64 (38%) NET patients: primary resection (n = 5), curative lymph node resection (n = 1), initiation/switch of chemotherapy (CTx) due to progressive disease (n = 10), no surgery due to systemic disease (n = 2), radiopeptide receptor therapy instead of CTx (n = 1), additional bisphosphonate therapy (n = 4), and hepatic brachytherapy (n = 1). In 12 of 24 (50%) of these patients, relevant findings were detected by a single submodality only: CT (n = 5), PET (n = 7); p for comparison = 0.774). Conclusion:⁶⁸Ga-DOTATOC-PET/CT influences therapeutic management in about one third of patients examined. CT and PET are comparably sensitive, deliver complementary information and equally contribute to therapeutic decision-making. Thus, despite the merits of the PET modality, the CT component must not be neglected and an optimized multiphase CT protocol is recommended.

We conclude that our modified superparamagnetic nanoparticles are stable under in vitro and in vivo conditions and are therefore applicable for efficient cell labeling and subsequent multimodal molecular imaging. Moreover, their multiple free amino groups suggest the possibility for further modifications and might provide interesting opportunities for various research fields.

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The purpose of this study was to evaluate the accuracy of MDCT for preoperative assessment of hepatic vascular anatomy and the identification of liver-transplantation (OLT) patients at risk of developing subsequent splenic artery steal syndrome (SASS). A total of 145 patients with liver cirrhosis who had undergone OLT and had pre-operative three-phase MDCT (4- to 64-rows) within 100 days before OLT were enrolled retrospectively. MDCT and 3Ds were reviewed by two independent blinded observers (O1/O2). Pre-operative imaging findings were correlated with intra-operative results; findings indicative for SASS were correlated with clinical data and DSA. Among all 145 patients, 16 patients (11%) showed accessory hepatic arteries (accuracy O1/O2, 97%; with 3Ds, 100%); 32 (22%) patients had replaced hepatic arteries (accuracy O1, 97%; O2, 95%; with 3Ds, 100%; kappa = 0.87 and 0.89, P < 0.001). Among 119 patients, 12 patients developed SASS after OLT. The logistic regression model revealed the spleen volume (P = 0.0105) as a predictive factor of SASS. With spleen volumes >or=829 ml, an accuracy of 75% for prediction of SASS was obtained. MDCT with three-dimensional post-processing (3Ds) was highly accurate for pre-operative hepatic vessel evaluation in patients before OLT. In addition, spleen volume was a predictive factor for developing SASS after OLT.

The cystic fibrosis transmembrane conductance regulator (CFTR) is recognized as a multifunctional protein that is involved in Cl؊ secretion, as well as acting as a regulatory protein. In order for acid secretion to take place a complex interaction of transport proteins and channels must occur at the apical pole of the parietal cell. Included in this process is at least one K ؉ and Cl ؊ channel, allowing for both recycling of K ؉ for the H,K-ATPase, and Cl ؊ secretion, necessary for the generation of concentrated HCl in the gastric gland lumen. We have previously shown that an ATP-sensitive potassium channel (K ATP ) is expressed in parietal cells. In the present study we measured secretagogue-induced acid secretion from wild-type and ⌬F508-deficient mice in isolated gastric glands and whole stomach preparations. Secretagogue-induced acid secretion in wildtype mouse gastric glands could be significantly reduced with either glibenclamide or the specific inhibitor CFTR-inh172. In ⌬F508-deficient mice, however, histamine-induced acid secretion was significantly less than in wild-type mice. Furthermore, immunofluorescent localization of sulfonylurea 1 and 2 failed to show expression of a sulfonylurea receptor in the parietal cell, thus further implicating CFTR as the ATP-binding cassette transporter associated with the K ATP channels. These results demonstrate a regulatory role for the CFTR protein in normal gastric acid secretion.

Summary To assess the accuracy of multirow detector computed tomography (MDCT) for the evaluation of renal anatomy for preoperative donor assessment in living related kidney transplantation. MDCT‐scans (4‐ and 16‐slice‐CT) of 51 consecutive living kidney donors (age, 51.6 ± 9.7 years; range, 28–68 years) were analysed by three blinded observers and compared with digital subtraction angiography (DSA) and surgery. Contrast‐enhanced MDCT was performed with 1 mm slice thickness reconstruction interval during arterial and venous phases. Supernumerary renal arteries, veins, early branching of vessels and abnormalities of the ureters were documented. The overall accuracy of computed tomography angiography (CTA) for detection and classification of surgically relevant arterial variants was 97% (99/102). The interpretation of 16‐channel MDCT images was correct in all cases (accuracy, 100%), while the four‐channel CTA had three incorrect results regarding the differentiation of early branching vessels from double renal arteries (accuracy, 93%). The overall accuracy of DSA was 91%. Renal vein abnormalities were correctly diagnosed with MDCT in 100% compared with 89% correct findings with DSA. There were three kidneys with incomplete ureter duplication, detected both with MDCT and DSA. MDCT demonstrated superior accuracy compared with non‐selective DSA for the preoperative assessment of renal anatomy in living kidney donors; and for the distinction of supernumerary arteries versus early branching patterns, 16‐channel CTA data were better than those of the four‐channel system.

Transplantation of primary human hepatocytes is a promising approach in certain liver diseases. For the visualization of the hepa-tocytes during and following cell application and the ability of a timely response to potential complications, a non-invasive modality for imaging the transplanted cells has to be established. The aim of this study was to label primary human hepatocytes with micron-sized iron oxide particles (MPIOs), enabling the detection of cells by clinical magnetic resonance imaging (MRI). Primary human hepatocytes isolated from 13 different donors were used for the labelling experiments. Following the dose-finding studies, hepatocytes were incubated with 30 particles/cell for 4 hrs in an adhesion culture. Particle incorporation was investigated via light, fluorescence and electron microscopy, and labelled cells were fixed and analysed in an agarose suspension by a 3.0 Tesla MR scanner. The hepatocytes were enzymatically resuspended and analysed during a 5-day reculture period for viability, total protein, enzyme leakage (aspartate aminotransferase [AST], lactate dehydrogenase [LDH]) and metabolic activity (urea, albumin). A mean uptake of 18 particles/cell could be observed, and the primary human hepatocytes were clearly detectable by MR instrumentation. The particle load was not affected by resuspension and showed no alternations during the culture period. Compared to control groups, labelling and resuspension had no adverse effects on the viability, enzyme leakage and metabolic activity of the human hepatocytes. The feasibility of preparing MPIO-labelled primary human hepatocytes detectable by clinical MR equipment was shown in vitro. MPIO-labelled cells could serve for basic research and quality control in the clinical setting of human hepatocyte transplantation.

• CT-guided interstitial brachytherapy (CTB) is a promising alternative to transarterial chemoembolization (TACE). • CTB instead of TACE is possible for bridging to liver transplantation in HCC patients. • HCC recurrence was not associated with CTB despite potential tumour seeding.