Reliability of a novel point of care device for monitoring diabetic peripheral neuropathy

We aimed to assess DPNCheck's reliability for repeated sural nerve conduction (NC) parameters. This post hoc analysis used data from the randomized controlled ACUDPN trial assessing NC of the N. Suralis every eight weeks over a 6-month period in 62 patients receiving acupuncture against diabetic peripheral neuropathy (DPN) symptoms. The reliability of DPNCheck for nerve conduction velocity and amplitude was assessed using intraclass correlation coefficients (ICC) and was calculated using data from single time points and repeated measures design. The results of the NC measurements were correlated with the Total Neuropathy Score clinical (TNSc). Overall, for both nerve velocity and amplitude, the reliability at each measurement time point can be described as moderate to good and the reliability using repeated measures design can be described as moderate. Nerve velocity and amplitude showed weak correlation with TNSc. DPNCheck's reliability results question its suitability for monitoring DPN's progression. Given the limitation of our analysis, a long-term, pre-specified, fully crossed study should be carried out among patients with DPN to fully determine the suitability of the device for DPN progression monitoring. This was the first analysis assessing the reliability of the DPNCheck for DPN progression monitoring using data from multiple collection time points.

Diagnosing the origin and impact of low-mode asymmetries in ignition experiments at the National Ignition Facility

Inertial confinement fusion ignition requires high inflight shell velocity, good energy coupling between the hotspot and shell, and high areal density at peak compression. Three-dimensional asymmetries caused by imperfections in the drive symmetry or target can grow and damage the coupling and confinement. Recent high-yield experiments have shown that low-mode asymmetries are a key degradation mechanism and contribute to variability. We show the experimental signatures and impacts of asymmetry change with increasing implosion yield given the same initial cause. This letter has implications for improving robustness to a key degradation in ignition experiments.

[DDB2-associated incidence of squamous cell carcinoma in Haflingers: risk minimization by genotyping]

INTRODUCTION

SCC (squamous cell carinomas) are among the most common eye neoplasms in horses. In recent studies Haflinger horses with a homozygous genotype for a missense variant in the DDB2 gene (damage specific DNA binding protein 2) had a significant increased risk of developing ocular SCC. The aims of this study were to determine the frequency of the SCC-associated risk allele in the DDB2 gene in Swiss and Austrian Haflinger populations and to validate the previously described phenotypic correlation. For this purpose, Haflingers presented at various horse clinics in Switzerland (n = 21, including 11 SCC cases), privately kept Haflingers (n = 52, including 1 SCC case), and Haflingers from a stud farm in the Austrian Tyrol (n = 53) were recruited. The individual DDB2 genotype of the animals was determined using a polymerase chain ceaction (PCR) test using hair follicle or whole blood samples. Of the 12 horses suffering from SCC, nine had ocular SCC and three had non-ocular SCC. Six of the nine Haflingers with ocular SCC and one of the three Haflingers with non-ocular SCC were homozygous for the DDB2 variant. Of the 113 clinically normal animals, 7/113 were homozygous (6 %) and 42/113 were heterozygous (37 %), which corresponds to an allele frequency of 24,8 % in the control cohort. The risk of ocular SCC occurring in Haflingers is significantly increased with the homozygous DDB2 genotype. However, not all animals with SCC carry this gene variant and not all DDB2 homozygous animals develop SCC, which can be explained by the multifactorial genesis of the disease. Due to the high frequency of the undesirable allele, we recommend taking the individual DDB2 genotype of breeding animals into account in order to avoid homozygous offspring with a greatly increased SCC risk by excluding high-risk matings.

Rev-erbα agonists suppresses TGFβ1-induced fibroblast-to-myofibroblast transition and pro-fibrotic phenotype in human lung fibroblasts

Idiopathic pulmonary fibrosis (IPF) is an interstitial lung disease characterized by excessive scarring of the lungs that can lead to respiratory failure and death. Lungs of patients with IPF demonstrate excessive deposition of extracellular matrix (ECM) and an increased presence of pro-fibrotic mediators such as transforming growth factor-beta 1 (TGFβ1), which is a major driver of fibroblast-to-myofibroblast transition (FMT). Current literature supports that circadian clock dysfunction plays an essential role in the pathophysiology of various chronic inflammatory lung diseases such as asthma, chronic obstructive pulmonary disease, and IPF. The circadian clock transcription factor Rev-erbα is encoded by Nr1d1 that regulates daily rhythms of gene expression linked to immunity, inflammation, and metabolism. However, investigations into the potential roles of Rev-erbα in TGFβ-induced FMT and ECM accumulation are limited. In this study, we utilized several novel small molecule Rev-erbα agonists (GSK41122, SR9009, and SR9011) and a Rev-erbα antagonist (SR8278) to determine the roles of Rev-erbα in regulating TGFβ1-induced FMT and pro-fibrotic phenotypes in human lung fibroblasts. WI-38 cells were either pre-treated/co-treated with or without Rev-erbα agonist/antagonist along with TGFβ1. After 48 h, the following parameters were evaluated: secretion of COL1A1 (Slot-Blot analysis) and IL-6 (ELISA) into condition media, expressions of α-smooth muscle actin (αSMA: immunostaining and confocal microscopy), and pro-fibrotic proteins (αSMA and COL1A1 by immunoblotting), as well as gene expression of pro-fibrotic targets (qRT-PCR: Acta2, Fn1, and Col1a1). Results revealed that Rev-erbα agonists inhibited TGFβ1-induced FMT (αSMA and COL1A1), and ECM production (reduced gene expression of Acta2, Fn1, and Col1a1), and decreased pro-inflammatory cytokine IL-6 release. The Rev-erbα antagonist promoted TGFβ1-induced pro-fibrotic phenotypes. These findings support the potential of novel circadian clock-based therapeutics, such as Rev-erbα agonist, for the treatment and management of fibrotic lung diseases and disorders.

Current Perspective on the Role of the Circadian Clock and Extracellular Matrix in Chronic Lung Diseases

The circadian clock is a biochemical oscillator that rhythmically regulates physiological and behavioral processes such as inflammation, immunity, and metabolism in mammals. Circadian clock disruption is a key driver for chronic inflammatory as well as fibrotic lung diseases. While the mechanism of circadian clock regulation in the lung has been minimally explored, some evidence suggests that the transforming growth factor β (TGFβ) signaling pathway and subsequent extracellular matrix (ECM) accumulation in the lung may be controlled via a clock-dependent mechanism. Recent advancements in this area led us to believe that pharmacologically targeting the circadian clock molecules may be a novel therapeutic approach for treating chronic inflammatory lung diseases such as asthma, chronic obstructive pulmonary disease (COPD), and idiopathic pulmonary fibrosis (IPF). Here, we update the current perspective on the circadian clock role in TGFβ1 signaling and extracellular matrix production during chronic lung diseases.

Construction and study of instrument response functions for analysis of the National Ignition Facility (NIF) neutron time-of-flight detectors

The analysis of the National Ignition Facility (NIF) neutron time-of-flight (nToF) detectors uses a forward-fit routine that depends critically on the instrument response functions (IRFs) of the diagnostics. The details of the IRFs used can have large impacts on measurements such as ion temperature and down-scattered ratio (DSR). Here, we report on the recent steps taken to construct and validate nToF IRFs at the NIF to an increased degree of accuracy, as well as remove the need for fixed DSR baseline offsets. The IRF is treated in two parts: a "core," measured experimentally with an x-ray impulse source, and a "tail" that occurs later in time and has limited experimental data. The tail region is calibrated with the data from indirect drive exploding pusher shots, which have little neutron scattering and are traditionally assumed to have zero DSR. Using analytic modeling estimates, the non-zero DSR for these shots is estimated. The impact of varying IRF tail components on DSR is investigated with a systematic parameter study, and good agreement is found with the non-zero DSR estimates. These approaches will be used to improve the precision and uncertainty of NIF nToF DSR measurements.

Echocardiographic assessment of left ventricular radial strain to differentiate cardiac amyloidosis from Fabry disease

Background

Left ventricular (LV) wall thickening is a typical echocardiographic finding in infiltrative cardiomyopathies like cardiac amyloidosis (CA) and Fabry disease (FD). The discrimination of both infiltrative diseases remains challenging by standard as well as 2D speckle tracking echocardiography (2DSTE)-based analysis of longitudinal LV strain patterns. Over the recent years, a constant development in image quality and data processing provided better possibilities to analyse layer specific myocardial deformation indices. With regards to FD, specific layer LV strain patterns may be useful to rule-in FD in patients with suspected infiltrative cardiomyopathy.

Purpose

The aim of the present study was to investigate differences and the diagnostic value of layer specific 2D STE-based radial LV strain indices in CA and FD.

Methods

Next to standard parameters of a comprehensive echocardiographic assessment (Vivid E9 or E95, GE Vingmed, Horton, Norway, with an M5S 1.5–4.5MHz transducer), we retrospectively analysed the transmural radial LV strain (GSradial), the subendocardial radial LV strain (GSendo), the subepicardial radial LV strain (GSepi), and the strain gradient (GSendo − GSepi) (EchoPAC software, GE) in FD patients and CA patient from the amyloidosis registry at our study site. A Receiver operating curve (ROC) analysis was used to assess the diagnostic value of the respective LV strain values and the layer-specific strain gradient to discriminate FD and CA.

Results

A total of 38 FD and 40 CA patients were included in our analyses. In patients with FD, GSepi showed a marked impairment. LV radial and layer strain were significantly reduced in CA compared to FD patients [GSradial −12.0 (−16.2 to −9.9) in CA vs. −17.7 (−20.5 to −14.6) in FD; p<0.001); GSendo (−20.6 (−27.0 to −15.7) in CA vs. −30.0 (−32.0 to −25.6) in FD; p<0.001); and GSepi (−7.4 (−8.9 to −4.8) in CA vs. −9.1 (−11.86 to −7.6) in FD; p<0.001)]. The gradient of GSendo and GSepi was significantly lower in patients with CA compared to FD (−14.0±5.6 in CA vs. −19.4±4.3 in FD respectively; p<0.001). GSendo held the highest diagnostic accuracy to discriminate CA and FD (area under the curve [AUC] 0.83, 95% confidence interval [CI] 0.73–0.92). The layer-specific strain gradient GSendo − Gsepi showed an AUC of 0.79 (CI 0.69 to 0.89).

Conclusion

Layer-specific strain analysis demonstrated significantly reduced strain values in CA patients compared to FD. The analysis of GSendo held a high diagnostic accuracy to discriminate FD and CA in patients. The integration of layer-specific LV strain indices into the diagnostic work-up may improve the management of patients with an unclear thick heart pathology in future.

Funding Acknowledgement

Type of funding sources: Private company. Main funding source(s): Alnylam Pharmaceuticals (Cambridge, MA, USA)

New echocardiographic approaches to differentiate cardiac amyloidosis and Fabry disease: the right heart and mitral valve thickness

Background

Infiltrative cardiomyopathies such as cardiac amyloidosis (CA) and Fabry disease (FD) are associated with high cardiovascular morbidity and mortality. Diagnosis is often challenging as CA and FD may present similar cardiac phenotypes on standard echocardiographic imaging, especially in early stages of disease.

Purpose

Our study focuses on right ventricular (RV) two-dimensional speckle tracking imaging and mitral valve thickness as diagnostic strategies to discriminate CA from FD. Here, we report preliminary data of our study registry of CA and FD patients.

Methods

We retrospectively screened patients with diagnosed CA or with genetically confirmed FD from our study registry. Global and free wall RV strain and mitral leaflet thickening in both groups were analysed using 2D speckle tracking echocardiography and linear measurements from a parastenal long axis view, respectively (Vivid E9 or E95, GE Vingmed, Horton, Norway, M5S 1.5–4.5MHz transducer). The diagnostic accuracy for discriminating CA and FD in both groups was evaluated using receiver operating characteristic (ROC) curve analysis.

Results

A total of 33 FD and 27 CA patients, including 17 patients with wild-type transthyretin-related (ATTR) CA, 8 patients with hereditary ATTR CA, one patient with light chain CA, and one patient with AA CA, were included. RV function was significantly reduced in CA compared to FD patients as measured by global longitudinal RV strain (−13.6±5.1 in CA vs. −18.4±3.9 in FD, p<0.001) and free wall longitudinal RV strain (−17.5±5.7 in CA vs. −21.3±4.4 in FD, p=0.005). Significantly lower longitudinal RV strain was observed in the basal to mid ventricular region in CA compared to FD patients, while RV apical strain was not significantly different between the two groups. RV global longitudinal strain had the highest diagnostic accuracy of strain analyses (area under the curve [AUC] 0.79, 95% confidence interval [CI] 0.66–0.93) to discriminate CA from FD. Additional measurement of the mitral valve in mid diastole in the parasternal long axis view revealed a significantly thickened leaflet in CA patients (4.6±1.2 mm in CA vs. 2.9±1.0 mm in FD, p<0.001) corresponding to an AUC of 0.84 (95% CI 0.72–0.96) in ROC analysis.

Conclusion

Global longitudinal RV strain was significantly reduced in CA patients while the mitral valve leaflets were significantly thickened compared to FD patients. Therefore, both parameters may be useful to discriminate CA from FD in the echocardiographic workup of patients with unclear left ventricular wall thickening.

Funding Acknowledgement

Type of funding sources: Other. Main funding source(s): Alnylam Pharmaceuticals (Cambridge, MA, USA)

A combined MeV-neutron and x-ray source for the National Ignition Facility

In support of future radiation-effects testing, a combined environment source has been developed for the National Ignition Facility (NIF), utilizing both NIF's long-pulse beams, and the Advanced Radiographic Capability (ARC) short pulse lasers. First, ARC was used to illuminate a gold foil at high-intensity, generating a significant x-ray signal >1 MeV. This was followed by NIF 10 ns later to implode an exploding pusher target filled with fusionable gas for neutron generation. The neutron and x-ray bursts were incident onto a retrievable, close-standoff diagnostic snout. With separate control over both neutron and x-ray emission, the platform allows for tailored photon and neutron fluences and timing on a recoverable test sample. The platform exceeded its initial fluence goals, demonstrating a neutron fluence of 2.3 ×10¹³ n/cm² and an x-ray dose of 7 krad.

Thermal decoupling of deuterium and tritium during the inertial confinement fusion shock-convergence phase

A series of thin glass-shell shock-driven DT gas-filled capsule implosions was conducted at the OMEGA laser facility. These experiments generate conditions relevant to the central plasma during the shock-convergence phase of ablatively driven inertial confinement fusion (ICF) implosions. The spectral temperatures inferred from the DTn and DDn spectra are most consistent with a two-ion-temperature plasma, where the initial apparent temperature ratio, T_{T}/T_{D}, is 1.5. This is an experimental confirmation of the long-standing conjecture that plasma shocks couple energy directly proportional to the species mass in multi-ion plasmas. The apparent temperature ratio trend with equilibration time matches expected thermal equilibration described by hydrodynamic theory. This indicates that deuterium and tritium ions have different energy distributions for the time period surrounding shock convergence in ignition-relevant ICF implosions.

Proof-of-concept of a neutron time-of-flight ellipsoidal detector

The time-resolved measurement of neutrons emitted from nuclear implosions at inertial confinement fusion facilities is used to characterize the fusing plasma. Several significant quantities are routinely measured by neutron time-of-flight (nToF) detectors in these experiments. Current nToF detectors use scintillators as well as solid-state Cherenkov radiators. The latter has an inherently faster time response and can provide a co-registered γ-ray measurement as well as improved precision in the bulk hot-spot velocity. This work discusses a nToF ellipsoidal detector that also utilizes a solid-state Cherenkov radiator. The detector has the potential to achieve a fast instrument response function allowing for characterization of the γ-ray burn history as well as the ability to field the detector closer to the fusion source. Proof-of-concept testing of the nToF ellipsoidal detector has been conducted at the National Ignition Facility using commercial optics. A time-resolved neutron signal has been measured from the diagnostic. Preliminary simulations corroborate the results.

Yersinia pseudotuberculosis serotype O:1 infection in a captive Seba's short tailed-fruit bat (Carollia perspicillata) colony in Switzerland

Background

Between February and April 2016, a slight increase in mortality was observed in a colony consisting of 400 captive Seba’s short-tailed bats (Carollia perspicillata). These animals cohabited with other nocturnal animal species in a dome of a private zoo in Switzerland.

Results

Gross and histological analysis of two (14.3%) out of the 13 animals submitted for necropsy within this period revealed a necrosuppurative pneumonia, hepatitis, splenitis, enterocolitis, and endometritis, with abundant intralesional colonies of Gram-negative rods. Yersinia (Y.) pseudotuberculosis serotype O:1 and biotype 1 belonging to the sequence type ST90 was isolated from the affected organs in both animals. Following this diagnosis, ¼ of the colony (99 animals) was culled and submitted for gross and histopathological analysis, and a bacterial culture selective for Yersinia spp. of lung, liver, and spleen was performed. From these 99 animals, one gravid female was tested and found to be positive for Y. pseudotuberculosis in the absence of clinical symptoms and histopathological lesions. PCR analysis of altogether three bacterial isolates for virulence factors revealed the presence of the ail gene, and one isolate was also positive for the virF and yadA plasmid genes.

Conclusions

These findings suggest that Carollia perspicillata are susceptible to lethal yersiniosis but do not represent a regular reservoir for Y. pseudotuberculosis. Culling of ¼ of the population was sufficient to limit the spread of this infection among the colony. Moreover, no infections were detected in cohabitant nocturnal animals and caretakers, indicating that the zoonotic risk in this case was low.

Acupuncture in diabetic peripheral neuropathy-protocol for the randomized, multicenter ACUDPN trial

BACKGROUND

Acupuncture is used to treat patients with diabetic peripheral neuropathy; however, the evidence is unclear. We present the design and methodology of the ACUDPN (ACUpuncture in Diabetic Peripheral Neuropathy) trial, which investigates the effectiveness of acupuncture for the treatment of diabetic peripheral neuropathy (DPN) symptoms. The aim of this study is to investigate whether acupuncture is effective for the treatment of DPN symptoms.

METHODS

This study is a two-armed, randomized, controlled, parallel group, open-label, confirmatory, multicenter trial (8-week intervention period plus 16 weeks of follow-up). Physicians in outpatient units in Germany who specialize in acupuncture treatment will treat 110 diabetes type II patients with clinical symptoms of peripheral neuropathy in the feet and legs with signs of neuropathy according to nerve conduction testing. The patients will be randomized in a 1:1 ratio to one of the following two groups: (a) semi-standardized acupuncture plus routine care or (b) routine care alone. Acupuncture will consist of 12 treatments per patient over 8 weeks. The primary outcome will be the overall DPN-related complaints in the extremities after 8 weeks as measured by the Visual Analog Scale (VAS). Further outcome measures will include DPN-related pain, the Neuropathic Pain Symptom Inventory (NPSI), Diabetic Peripheral Neuropathic Pain Impact (DPNPI) scores, and nerve conduction parameters of the sural nerve at weeks 8, 16, and 24.

DISCUSSION

The results of this trial will be available in 2021 and will help clarify whether acupuncture can be considered effective for the treatment of DPN with regard to the subdimensions of the neuropathic clinical picture.

TRIAL REGISTRATION

ClinicalTrials.gov NCT03755960 . Registered on 11 August 2018.

Modeling the one-dimensional imager of neutrons (ODIN) for neutron response functions at the Sandia Z facility

The one-dimensional imager of neutrons (ODIN) at the Sandia Z facility consists of a 10-cm block of tungsten with rolled edges, creating a slit imager with slit widths of either 250, 500, or 750 μm. Designed with a 1-m neutron imaging line of sight, we achieve about 4:1 magnification and 500-μm axial spatial resolution. The baseline inertial confinement fusion concept at Sandia is magnetized liner inertial fusion, which nominally creates a 1-cm line source of neutrons. ODIN was designed to determine the size, shape, and location of the neutron producing region, furthering the understanding of compression quality along the cylindrical axis of magnetized liner implosions. Challenges include discriminating neutrons from hard x-rays and gammas with adequate signal-to-noise in the 2 × 10¹² deuterium-deuterium (DD) neutron yield range, as well as understanding the point spread function of the imager to various imaging detectors (namely, CR-39). Modeling efforts were conducted with MCNP6.1 to determine neutron response functions for varying configurations in a clean DD neutron environment (without x-rays or gammas). Configuration alterations that will be shown include rolled-edge slit orientation and slit width, affecting the resolution and response function. Finally, the experiment to determine CR-39 neutron sensitivity, with and without a high density polyethylene (n, p) converter, an edge spread function, and resolution will be discussed.

3-Phase bone imaging and SPECT in the follow up of patients with allogenic vascularized knee joint transplants

Vascularized allotransplantation of knee joints under immunosuppression is a novel approach in orthopedic surgery. During the postoperative course immunosuppressive management depends on perfusion and viability of the graft. Aim: Evaluation of different diagnostic tools in regard to their usefulness and reliability to provide information about microvascularity and viability of vascularized knee joint allografts. Methods: Four patients with allogenic knee joint transplants were studied up to 26 months after transplantation with 3-phase bone scans and SPECT. The results were compared with duplex sonography, angiography, and histology. Results: Two cases without complications were characterized by adequate perfusion in duplex sonography, angiography and early bone scans. Late bone scans demonstrated increased bone metabolism of the transplant. Corresponding biopsy revealed viable bone cells. In one case with partial thrombosis and one case with complete thrombosis of the transplant vessels rapidly decreasing or missing perfusion was detected by duplex sonography, angiography, and bloodpool scintigraphy. Late bone scans showed reduced or absent bone metabolism. Biopsy demonstrated necrotic bone tissue. Due to the advantage of a tomographic technique SPECT allowed a more reliable assessment of graft viability as compared to planar imaging. Conclusion: Our findings confirm bone scintigraphy as a valuable diagnostic tool in patients with allogenic vascularized knee joint transplants. In contrast to other diagnostic approaches, scintigraphy provides reliable information on both viability and perfusion of the transplant within a single noninvasive clinical investigation.

Szintigraphische Verwendung von 87 bei der 90Y-Therapie von Knochenmetastasen

Durch Zyklotron-Bestrahlung von Rb (α, xn) läßt sich trägerfreies 87Y hersteilen. Es zerfällt mit einer Halbwertzeit von 80,3 h bei Aussendung von Gammalinien in Höhe von 0,48 und 0,39 MeV über 87mSr in das stabile 87Sr. Die bisher an 6 Patienten gewonnenen Erkenntnisse zeigen eine gute bildliche Darstellung sowie Übereinstimmung der 99mTc-DPD- und 87Y-Scans. Eine quantitative Auswertung der 87Y-Scans bezüglich der Aktivitätsanreicherung in den Knochenmetastasen zum übrigen Knochen und Weichteilgewebe ist derzeit in Bearbeitung. Aussagen über die Biokinetik bei der 90Y-Therapie, Ermittlung von Anreicherungsfaktoren und der biologischen Halbwertzeit bilden Voraussetzungen für eine Dosisberechnung. Zur Vermeidung einer Umweltbelastung sollten diagnostische Untersuchungen dieser Art nur in Therapiezentren durchgeführt werden, die über eine Abklinganlage verfügen.

Intraindividueller Vergleich der Magenperistaltik nach Gabe von semiliquiden und festen Testmahlzeiten

Ziel: An einem heterogenen Kollektiv von Patienten mit gastrointestina-len Beschwerden wurde der Einfluß von Testspeisen unterschiedlicher Konsistenz auf Peristaltik und Entleerungsrate des Magens untersucht. Methodik: Bei 12 Patienten wurde nach Gabe von radioaktiv markierter semiliquider sowie fester Testspeise eine konventionelle Magenfunktionsszintigraphie durchgeführt. Zusätzlich zu der Standardauswertung mit Zeit-Aktivitätskurven wurden für zwei festgelegte Zeitintervalle (Früh- und Spätphase) kondensierte Bildsequenzen erstellt, auf deren Grundlage mittels Fourier-Analyse Amplitude und Frequenz der Magenkontraktionen ermittelt wurden. Ergebnisse: Erwartungsgemäß wurde die Magenentleerung von der Konsistenz der Testspeise beeinflußt. Feste Speisen wurden langsamer entleert als die semiliquide Mahlzeit (p <0,01). Dagegen hingen Amplitude und Frequenz der Magenkontraktionen nicht von der Konsistenz der verabreichten Testspeise ab. Mit fortschreitender Untersuchungsdauer/Magenentleerung fand sich sowohl bei Studien mit semiliquider als auch fester Testspeise ein signifikanter Anstieg der Kontraktionsamplituden (p <0,05). Die Kontraktionsfrequenz zeigte keine zeitliche Abhängigkeit. Schlußfolgerung: An intraindividuell erhobenen Vergleichsdaten ließ sich belegen, daß, im Gegensatz zur Entleerungsrate, Amplitude und Frequenz der Magenkontraktionen nicht von der Konsistenz einer verabreichten Testspeise abhängen. Aufgrund der deutlich kürzeren Untersuchungszeit und einfacheren Zubereitung sind semiliquide Testspeisen in der Routinediagnostik zu bevorzugen. Änderungen der Kontraktionsamplitude im zeitlichen Verlauf legen eine standardisierte Vorgehensweise bei der Datenaufzeichnung nahe.

111In-Octreotide- und 123I-MIBG-Szintigraphie in der Diagnostik von Dünndarmkarzinoiden

Ziel: Ziel dieser Studie war, die diagnostische Aussagekraft der 111In-Oc-treotide- und der 123I-MIBG-Szintigraphie an einem größeren Patientengut in der Diagnostik von Karzinoiden zu vergleichen und mit computertomographischen Befunden zu korrelieren. Methoden: Bei 28 Patienten wurden in engem zeitlichen Intervall eine Octreotide-, MIBG-Szintigraphie und Computertomographie durchgeführt. Ergebnisse: Bei 13/15 präoperativ untersuchten Patienten konnte eine Rezeptorexpression des Primärtumors mit Octreotide nachgewiesen werden, eine MIBG-Speicherung lediglich bei 8/15 Fällen. Lebermetastasen waren im Octreotide-Szintigramm in 26 Fällen nachweisbar, mit MIBG in 19 Fällen, computertomographisch bei 22 Patienten. Die Zahl der gefundenen Herde war mit MIBG und CT geringer als mit Octreotide. Drei Patienten wiesen bisher unbekannte, extrahepatische Octreotide-Mehrspeiche-rungen auf, 2 davon zeigten keine MIBG-Speicherung. Fünf nichthormonaktive Tumoren waren im MIBG-Szintigramm negativ, wurden aber im Octreotide-Szintigramm nachgewiesen. Schlußfolgerung: Hinsichtlich der diagnostischen Möglichkeiten ist die Octreotide-Rezeptor-szintigraphie der MIBG-Szintigraphie deutlich überlegen. Somit bringt die Durchführung der MIBG-Szintigraphie nach der vorliegenden Studie keinen diagnostischen Zugewinn und erscheint nur im Hinblick auf eine eventuelle 131I-MIBG-Therapie sinnvoll.

Beurteilungskriterien für die Captopril-Nierenfunktions- szintigraphie mit 99mTc-MAG3

Im Rahmen der Diagnostik der renovaskulären Hypertonie hat die Nierenfunktionsszintigraphie unter Einfluß eines ACE-Hemmers als nichtinvasives Verfahren erhebliche Bedeutung erlangt. Unter Einsatz des Radiopharmazeutikums 99mTc-MAG3 wurden bei 54 Nieren mit angiographisch, klinisch und endokrinologisch gesicherter Diagnose folgende szintigraphischen Parameter isoliert auf ihre Aussagekraft zum Nachweis bzw. Ausschluß einer relevanten Nierenarterienstenose untersucht: parenchymaler Nuklidtransport, Harnabflußsituation, Nierengröße und seitengetrennte Funktionsanteile. Als typischer Befund einer dekompensierten Nierenarterienstenose erwies sich eine ausgeprägte parenchymale Nuklidretention in Kombination mit einer deutlich verzögerten Harnaktivitätsanflutung im Nierenhohlraumsystem. Im Vergleich zur rein visuellen Beurteilung der Sequenzszintigramme erbrachte die Miteinbeziehung zusätzlicher, quantitativer Kriterien im eigenen Patientenkollektiv keine diagnostischen Vorteile. Bei 43 Patienten mit klinischen Hinweisen auf eine renovaskuläre Hypertonie ergab sich mit diesen Kriterien eine Sensitivität von 89%, die Spezifität betrug 88%. Bilateral positive Befunde erwiesen sich als unspezifisch; blieben diese unberücksichtigt, erhöhte sich die Spezifität der Untersuchung auf 100%.

Diagnostik des »Sentinel Lymph Node« bei malignem Melanom: präoperative Lymphszintigraphie und intraoperative Sondenmessung

Ziel: Der »sentinel lymph node« (SLN) reflektiert den Befall der nachfolgenden Lymphknoten-Stationen bei Patienten mit malignem Melanom und hat damit eine erhebliche prognostische Bedeutung. Ziel der Studie war die prä- und intraoperative Lokalisierung dieses Lymphknotens mittels Lymphszintigraphie und Sondenmessung. Methoden: 38 Patienten mit malignem Melanom (Tiefenausdehnung >0,75 mm) wurden nach Injektion von 40 MBq 99Tc-Nanocoll szintigraphisch untersucht. Die Position des ersten im Abflußgebiet dargestellten Lymphknotens wurde an der Haut markiert. Unmittelbar danach wurde intraoperativ mittels einer kollimierten Sonde dieser Lymphknoten aufgesucht und nach Ex- stirpation die Aktivität des Knotens und die Restaktivität im Operations- situs gemessen. Ergebnisse: Bei allen Patienten konnte der SLN szintigraphisch lokalisiert und markiert werden. Vor und nach Exstirpation wurde die höchste Aktivität mit der Sonde im markierten Lymphknoten bestimmt. Makroskopisch und im Ultraschall und CT waren alle Lymphknoten unauffällig. Histologisch zeigten acht Patienten eine Metastasierung im lokalisierten Lymphknoten, die bei sieben Patienten eine großzügige Ausräumung des gesamten nachfolgenden Lymphgebietes nach sich zog. Schlußfolgerungen: Die vorgestellte Methode bietet die Möglichkeit, den morphologisch unauffälligen SLN sicher aufzufinden. Die operative Entfernung des diagnostisch erkannten SLN kann eine grundlegende Zäsur in der Therapie des malignen Melanoms bedeuten, da nur bei positivem Befund eine großzügige Lymphknoten-Ausräumung durchgeführt wird. Die kombinierte Lymphszintigraphie mit Sondenmessung beeinflußt entscheidend das therapeutische Vorgehen aufgrund der sicheren Lokalisation des Lymphknotens und ermöglicht hierdurch eine individuelle Therapieplanung.

Lymphsequenzszintigraphie für die nichtinvasive Langzeitbeobachtung des funktionellen Therapieerfolges nach Transplantation autologer Lymphgefäße

Ziel: Die autologe Lymphgefäßtransplantation führt bei bestehendem Lymphödem zu einer signifikanten Verbesserung der Lymphabflußverhältnisse. Die vorliegende Studie untersucht, ob die Lymphsequenzszintigraphie geeignet ist, die persistierende Funktion autologer Lymphgefäßtransplantate und damit den Erfolg dieser Operationsmethode zu dokumentieren. Methoden: In die Studie gingen die Daten von 20 Patienten (17 Frauen und 3 Männer) ein. Anlaß für die Operation war in 4 Fällen ein primäres, in 16 Fällen ein sekundäres Lymphödem. Szintigraphi-sche Analogaufnahmen mit semiquantitativer Beurteilung des Lymphtransportes erfolgten als Ausgangsuntersuchung vor Transplantation und anschließend über einen Zeitraum von sieben Jahren. Ergebnisse: Bei 17 von 20 Patienten (Transplantationssitus: obere Extremität n = 12, untere Extremität n = 8) war postoperativ eine persistierende Verbesserung des Lymphtransportes im Vergleich zur präoperativen Situation an einem signifikanten Abfall der Transportindices nachweisbar. Bei 5 Patienten gelang zusätzlich die direkte szintigraphische Darstellung der Lymphgefäßtransplantate. In diesen Fällen konnte postoperativ ein signifikant höherer Abfall der Transportindices im Vergleich zu Patienten ohne szintigraphisch darstellbares Transplantat beobachtet werden. Lediglich 3 der 20 Patienten zeigten keine Besserung im Vergleich zur Ausgangssituation. Schlußfolgerungen: Somit erwies sich die Lymphsequenzszintigraphie mit semiquantitativer Einschätzung der Lymphabflußverhältnisse vor und nach autologer Lymphgefäßtransplantation als einfache, nicht invasive Untersuchungsmethode zur objektiven Beurteilung des Therapieerfolges im Langzeitverlauf. Eine szintigraphisch direkte Darstellung des autologen Lymphgefäßtransplantats scheint einen prognostisch günstigen Faktor bezüglich der postoperativen Lymphdrainage darzustellen.

Advantages and limitations of whole-body bone marrow MRI using turbo-STIR sequences in comparison to planar bone scans

At modern MRI tomographs the whole body can be screened for bone marrow metastases within 45 min. Aim of this study was to evaluate the diagnostic advantages and disadvantages of a whole-body bone marrow MRI protocol using Turbo Short Tau Inversion Recovery [STIR] sequences in comparison to planar bone scintigraphy (SZ). Patients and methods: In order to screen for bone metastases within two weeks SZ and whole-body MRI with Turbo-STIR-sequences were performed in 20 patients with known breast cancer. For further evaluation five regions were defined: scull, spine including the pelvis, femora, humeri and ribs including scapulae and sternum. Results: In 9/20 patients neither with SZ nor with MRI bone metastases were detected (staging M0). Among the remaining 11 patients SZ detected 109 and MRI 150 lesions which were typical for bone metastases. All of these 11 patients were staged Ml correspondingly with both methods. Within the thorax (ribs, sternum, scapulae) MRI discovered only 6/17 and within the scull 0/6 lesions which were suspicious for metastases in SZ. Inversely MRI identified much more metastatic lesions than SZ within the femora (20/16), the humeri (14/12) and the spine including the pelvis (110/58). Conclusions: Susceptibility-, truncation*, chemical-shift-, third arm- and particularly pulsation artifacts along with the impossibility to chose slice orientation equally advantageous for all regions of the body cause impaired image quality of MRI whole body scanning. Therefore, concerning the detection rate of bone metastases within the thorax (ribs, sternum and scapulae) and the scull, conventional Turbo-STIR-MRI whole-body scans are even less accurate than conventional planar bone scintigraphy in those regions.

Metastases in patients with malignant melanoma despite of negative sentinel lymph node: Has the concept to be changed?

Aim: The Sentinel Lymph Node (SLN) is of considerable prognostic relevance, because extended lymph node dissection may not be performed in patients presenting with histologically negative SLN. The aim of the present study was to prove the prognostic value of the SLN-concept in these patients. Methods: So far the clinical follow-up of 162 patients with histologically proven malignant melanoma and metastatically uninvolved (negative) SLN was investigated. Histological examination included standard methods (HE-Test) and special histochemical techniques (S-100, HMB-45). All patients underwent clinical examination, ultrasonic diagnosis of the regional lymph nodes, and x-ray of the chest every 3 months. Results: Despite of negative SLN-findings in 8/162 patients metastases of the malignant melanoma were found after a time period of 5-27 months. Three patients presented with recurrence in the previously mapped (negative) SLN-basin. In another case the scintigraphically visualized SLN could not be identified intraoperativelly by means of the hand-held gamma probe. One patient showed intransit-metastases or skin-metastases, respectively; another patient recurred in the scar area. One patient showed hematogenic dissemination (liver) which is not detectable by lymphoscintigraphy; in another patient metastases were found outside the primary lymphatic basin (cervical). Conclusion: In our patient group 4,9% presented with metastases despite negative SLN while published data report up to 11% (observation period 35 months), among them only 3 patients (1,9%) being real concept failures. Our results underline that there is no evidence to change this concept in patients with clinically early stage.

First experiences with a new radiopharmaceutical for sentinel lymph node detection in malignant melanoma

Aim of this study was to localize the sentinel lymph node by lymphoscintigraphy using technetium-99m colloidal rhenium sulphide (Nanocis®), a new commercially available radiopharmaceutical. Due to the manufacturers’ instructions it is licensed for lymphoscintigraphy. Patients, methods: 35 consecutive patients with histologically proved malignant melanoma, but without clinical evidence of metastases, were preoperatively examined by injecting 20-40 MBq Nanocis® with (mean particle size: 100 nm; range: 50-200 nm) intradermally around the lesion. Additionally blue dye was injected intaoperatively. A hand-held gamma probe guided sentinel node biopsy. Results: During surgery, the preoperatively scintigraphically detected sentinel lymph nodes were identified in 34/35 (97%) patients. The number of sentinel nodes per patient ranged from one to four (mean: n = 1.8). Histologically, metastatic involvement of the sentinel lymph node was found in 12/35 (34%) patients; the sentinel lymph node positive-rate (14/63 SLN) was 22%. Thus, it is comparable to the findings of SLN-mapping using other technetium-99m-labeled nanocolloides. Conclusion: 99mTc-bound colloidal rhenium sulphide is also suitable for sentinel node mapping.

Lymph kinetics with technetium-99m labeled radiopharmaceuticals

Aim of this study was to characterize suitable technetium- 99m labeled tracers for lymphoscintigraphy by comparative animal tests. Animals, methods: To evaluate the influence of the particle size and the organ tracer-uptake on lymphtransport animal experiments were performed on six different agents (including one control group). Activity distributions were examined in Sprague-Dawley-rats by lymphoscintigraphy; the maximum uptake (count-rate) of the whole body and in lymph nodes were analyzed by regions- of-interest-technique, respectively. Additionally, for characterization of lymphatic and extralymphatic traceruptake an intra-individual relative count-rate ratio of the liver, lung, kidneys, and spleen has been calculated following organ extraction. Results: Organ specific differences of distribution were clearly demonstrated. Our results indicate that the kinetics of lymphoscintigraphic 99mTc-bound agents substantially depends on particle size. Reliable transport from the interstitium to initial lymph vessels and lymph node uptake suggested for tracers suited for lymphoscintigraphy a median size of about <100 nm. Conclusion: Our data could improve standardization of diagnostic methods and lead to an objective consideration of therapeutic procedures.

DMSA-scintigraphy in paediatrics: Is the evaluation of the geometric mean necessary for the calculation of the differential renal function?

For assessment of differential renal function (PF) by means of static renal scintigraphy with Tc-99m-dimer-captosuccinic acid (DMSA) the calculation of the geometric mean of counts from the anterior and posterior view is recommended. Aim of this retrospective study was to find out, if the anterior view is necessary to receive an accurate differential renal function by calculating the geometric mean compared to calculating PF using the counts of the posterior view only. Methods: 164 DMSA-scans of 151 children (86 f, 65 m) aged 16 d to 16 a (4.7 ± 3.9 a) were reviewed. The scans were performed using a dual head gamma camera (Picker Prism 2000 XP, low energy ultra high resolution collimator, matrix 256 x 256,300 kcts/view, Zoom: 1.6-2.0). Background corrected values from both kidneys anterior and posterior were obtained. Using region of interest technique PF was calculated using the counts of the dorsal view and compared with the calculated geometric mean [SQR(Ctsdors x Ctsventr]. Results: The differential function of the right kidney was significantly less when compared to the calculation of the geometric mean (p<0.01). The mean difference between the PFgeom and the PFdors was 1.5 ± 1.4%. A difference > 5% (5.0-9.5%) was obtained in only 6/164 scans (3.7%). Three of 6 patients presented with an underestimated PFdors due to dystopic kidneys on the left side in 2 patients and on the right side in one patient. The other 3 patients with a difference >5% did not show any renal abnormality. Conclusion: The calculation of the PF from the posterior view only will give an underestimated value of the right kidney compared to the calculation of the geometric mean. This effect is not relevant for the calculation of the differntial renal function in orthotopic kidneys, so that in these cases the anterior view is not necesssary. However, geometric mean calculation to obtain reliable values for differential renal function should be applied in cases with an obvious anatomical abnormality.

Guideline on radiation protection in medicine requires documentation of radioiodine therapy and follow-up

Aim: The lately updated German guideline on radiation protection in medicine (Richtlinie Strahlenschutz in der Medizin) requires the physician who administers radioactive substances for therapy, to perform and document follow-ups. In order to decrease the administrative burden, an electronic database was developed that interfaces with a word processing software to generate written reports and statistic analysis. Methods: Based on Microsoft® Access and Microsoft® Visual Basic a database was created to monitor patients with benign and malignant thyroid disorders after radioiodine therapy. It permits automatic creation of therapy documents and necessary patient reports in Microsoft® Word. Intuitive handling, third level of normalization in database architecture and automatic plausibility checks guarantee integrity of the data and the efficacy of the database. Results, conclusion: The new software has been a success in over 1500 patients and over 3800 in- and outpatient therapies and visits. The effort of data entry is easily offset by the automatic generation of the necessary patient reports. The required supervision of the follow-up appointments is now also user-friendly and efficient.

Radiation exposure of patients undergoing nuclear medicine procedures in Germany between 1996 and 2000

The aim of this study was to estimate both the frequency and effective dose of nuclear medicine procedures performed in Germany between 1996 and 2000 for different subgroups of patients. Methods: Electronically archived data from 14 hospitals and 10 private practices were restored and statistically analyzed. The effective dose per examination was calculated according to ICRP publication 80 using the tissue weighting factors given in ICRP publication 60. Based on the data collected, statistical parameters were computed to characterize the frequency and effective dose of the various nuclear medicine procedures. Results: In total, 604,771 nuclear medicine procedures performed in 433,709 patients were analyzed. On average, 1.4 examinations were carried out per patient and year. The median effective dose was 1.7 [5.-95. percentile; mean: 0.4–8.5; 2.9] mSv per examination and 2.3 [0.5–11.2; 3.5] mSv per patient. Interestingly, the mean effective dose per examination, but not the number of examinations per year increased with the age of the patients. Most frequent were examinations of the thyroid (36.7%), the skeleton (27.1%) and the cardiovascular system (11.1%), which were associated with a median effective dose of 0.5 [0.5–1.1; 0.7] mSv, 3.4 [2.9–5.1; 3.6] mSv and 7.3 [3.2–21.0; 9.5] mSv, respectively. Over the five-year period examined, the total annual number of PET procedures (222.3%) as well as of examinations of thyroid (24.5%), skeleton (17.9%), and the cardiovascular system (14.9%) increased markedly, whereas a decrease was observed for brain (-39.3%), lung (-20.2%) and renal (-15.0%) scans. Conclusion: The age- and gender-specific data presented in this study provide detailed public health information on both the current status and recent trends in the practice of diagnostic nuclear medicine examinations.

Initial experience with locoregional radioimmunotherapy using 131I-labelled monoclonal antibodies against tenascin (BC-4) for treatment of glioma (WHO III and IV)

Aim: None of the established treatments (surgery, radiotherapy, chemotherapy) for malignant glioma has improved its very poor prognosis. Adjuvant locoregional radioimmunotherapy (RIT) represents a new therapeutic approach. We present our initial experience with this therapeutic tool with respect to adverse effects, biokinetics and clinical follow-up. Methods: Following surgery and radiotherapy, 12 patients with glioma (4, WHO stage III; 8, WHO stage IV) underwent 1-5 RIT-cycles (average dose 1100 MBq 131labelled monoclonal BC-4 antibodies) at six week intervals. Follow-up included serial FDG-PET and MRI investigations. Evaluation of biokinetics included whole body scans, together with analysis of blood, urine and fluid from the tumor cavity. Results: Following RIT, four patients experienced temporary seizures, which, in one case, were associated with temporary aphasia. Eight patients developed HAMA (human anti-mouse antibodies) during follow-up. Mean biologic half-life of the radiopharmaceutical in the resection cavity was 3.9 d (range: 1.0-10.2 d) and remained stable intraindividually during further RIT-cycles. The antibody/radionuclide conjugate remained stable in the tumor cavity for at least 5 d. Median survival presently stands at 18.5 months compared to 9.7 months in a historical patient group (n = 89) undergoing conventional therapeutic strategies. Five patients show no signs of recurrence. In three patients with post-surgical evidence of residual tumor, one patient showed partial remission, one stable disease, and one progressive disease during RIT. Four patients without evidence of residual tumor mass at the beginning of RIT developed recurrence during therapy. Conclusions: Initial experience demonstrates that locoregional RIT is a well tolerated treatment modality that may represent a promising new approach in the management of patients with malignant glioma. Advantages of local application include passage of the blood-brain barrier, high concentration of activity within the resection cavity and low systemic toxicity.

Stunning effects in radioiodine therapy of thyroid carcinoma

In radioiodine therapy for malignant thyroid disease, the pre-therapeutically administered iodine-131-dose can reduce the potential of thyroid or thyroid carcinoma cells to absorb the following therapeutic iodine-131-dose, possibly leading to its failure. This so called stunning effect is controversially discussed in the scientific community. Here we summarize and evaluate publications with regard to the existence and the effects of stunning as well as possible countermeasures.

Aquisition of age- and sex-dependent patient data for the calculation of annual radiation exposure in nuclear medicine: a German pilot study

Aim: A pilote study for estimation of radiation exposure due to diagnostic procedures in nuclear medicine using routine data of hospitals and practices in Germany. Methods: Hospitals and practices willing to participate in the study supplied data of one year (1997), containing information on patients´ identification number, age, sex, type of diagnostic procedure, radiopharmaceutical, administered activity, type of health insurance (private/ public), inpatient/outpatient status, and so-called Leistungsziffer, which describes the type of medical performances in Germany. The effective dose per examination was calculated according to ICRP 80. Mean, standard deviation, median, 5th and 95th percentiles of the effective dose were calculated, stratified by type of organ system and also by sex and age, including patients of ≥18 years. Results: 82 039 examinations from patients of 9 hospitals and practices were analyzed. The median (5-95th percentiles) of the effective dose per examination for all patients was 2.9 mSv (0.4-8.5 mSv); 1.2 examinations per patient and year were performed on average. The three most frequent examinations were bone scans (median 3.4 mSv; 2.9-5.1), thyroid (0.9 mSv; 0.4-2.2) and cardiovascular studies (7.3 mSv; 3.8-20.2). The median effective dose for 18 to 40 years old women was 1.0 mSv (0.4-5.8), for women between 41 and 65 years 2.2 mSv (0.4-7.3) and for women older than 65 years 2.4 mSv (0.5- 7.6). The corresponding values for men were 2.6 mSv (0.3-7.6); 3.3 mSv (0.4-9.1), and 3.4 mSv (0.5- 8.8). Conclusion: It was possible to gain an accurate determination of radiation exposure of diagnostic procedures in nuclear medicine by routine data.

Colorectal cancer patients before resection of hepatic metastases

Aim: Evaluation of the role of FDG-PET in comparison to conventional staging methods for detecting extrahepatic tumour deposits prior to resection of liver metastases. Patients, Methods: In our prospective study, 58 patients (24 women, 34 men; age 33-81 years) with liver metastases of colorectal carcinoma underwent FDG-PET. Images were acquired in 3D-mode including transmission scans and reconstructed iteratively. For conventional staging all patients underwent abdominal ultrasound, helical computed tomography (CT) of the thorax and abdomen, and colonoscopy/rectoscopy. A preliminary therapeutic decision was established without knowledge of the FDG-PET findings. Thereafter, it was revised or confirmed according to the results of FDG-PET. Results: In 3/58 patients extrahepatic tumour deposits were concordantly identified with both conventional staging methods and FDG-PET. However, in one case, both conventional methods and FDG-PET were false positive regarding pulmonary metastases. In 12/58 patients, nothing but FDG-PET detected extrahepatic tumour masses, which were later confirmed either by histology or follow-up. Conclusion: Our study suggests that in 21% of patients exclusively FDG-PET is an appropriate diagnostic tool to reveal extrahepatic metastases or local recurrence of colorectal carcinoma. Our results demonstrate that FDG-PET provides relevant additional information for accurate therapeutic planning as compared to the conventional combination of staging methods. Therefore, FDG-PET has to exert a decisive influence on the decision for resection of hepatic metastases.

Scintimammography using 99mTc sestamibi – use and limitations

Aim: Until now scintimammography did not achieve any definite role in the assessment of breast lesions. Purpose of this study was to elaborate its use as well as the limitations of scintimammography after 500 examinations completed. Methods: Scintigraphic findings were correlated with the histopathologic outcome of 219 patients, who underwent surgery or biopsy for histopathological confirmation. The results were determined with respect to palpability of the lesion and tumour size. Additionally, a distinct analysis was performed for the patient subpopulation with indeterminate results of previously performed physical examination, mammography, and sonography. Results: Overall sensitivity for scintimammography was 82.1% at a specificity of 87.5%. For palpable lesions sensitivity was 91.7% which was evidently higher as compared to 64.9% for non palpable lesions. For palpable lesions specificity was 81.1% and 88.6% for non palpable lesions. According to tumour size sensitivity ranged between 65.2% for carcinoma with a diameter <1 cm and 93.7% for carcinoma >1 cm. In the patients subgroup with indeterminate preliminary diagnosis (n = 143) sensitivity decreased to 71.7% at a specificity of 87.8%. Patients undergoing neoadjuvant chemotherapy showed decreasing sestamibi uptake as early as 8 days after therapy if tumour response was evident. However, small residual invasive tumours in patients with complete remission could not be visualised. Conclusion: Scintimammography is neither suited for screening, nor early diagnosis of breast cancer, nor for the further evaluation of small and unclear mammographic findings. Scintimammography should not be used whenever histopathological clarification of a suspicious lesion is necessary. It is useful to further investigate patients with unclear or probably benign findings in physical examination and/or mammography and to monitor tumour response to neoadjuvant chemotherapy.

[F-18]FDG imaging of head and neck tumors: Comparison of hybrid PET, dedicated PET and CT

Aim: Aim of the study was to evaluate [F-18] FDG imaging of head and neck tumors using a Hybrid-PET device of the 2nd or 3rd generation. Examinations were compared to dedicated PET and Spiral-CT. Methods: 54 patients suffering from head and neck tumors were examined using dedicated PET and Hybrid-PET after injection of 185-350 MBq [F-18] FDG. Examinations were carried out on the dedicated PET first followed by a scan on the Hybrid-PET. Dedicated PET was acquired in 3D mode, Hybrid-PET was performed in list mode using an axial filter. Reconstruction of data was performed itera-tively on both, dedicated PET and Hybrid-PET. All patients received a CT scan in multislice technique. All finding have been verified by the goldstandard histology or in case of negative histology by follow up. Results: Using dedicated PET the primary or recurrent lesion was correctly diagnosed in 47/48 patients, using Hybrid-PET in 46/ 48 patients and using CT in 25/48 patients. Metastatic disease in cervical lymph nodes was diagnosed in 17/ 18 patients with dedicated PET, in 16/18 patients with Hybrid-PET and in 15/18 with CT. False positive results with regard to lymph node metastasis were seen with one patient for dedicated PET and Hybrid-PET, respectively, and with 18 patients for CT. In a total of 11 patients unknown metastastic lesions were seen with dedicated PET and with Hybrid-PET elsewhere in the body. Additional malignant disease other than the head and neck tumor was found in 4 patients. Conclusion: Using Hybrid-PET for [F-18] FDG imaging reveals a loss of sensitivity and specificity of about 1-5% as compared to dedicated PET in head and neck tumors. [F-18] FDG PET with both, dedicated PET and Hybrid-PET is superior to CT in the diagnosis of primary or recurrent lesions as well as in the assessment of lymph node involvement.

Skelettszintigraphische Befunde bei der Psoriasis

Bei insgesamt 382 Patienten mit Psoriasis wurden seit 1973 Knochenszintigraphien mit 99mTc-Phosphat-Verbindungen durchgeführt. Zum Vergleich der nuklearmedizinischen Ergebnisse mit dem röntgenologischen und dem klinischen Befund wurde eine Gesamtgruppe von 121 rheumaserologisch negativen Patienten mit Psoriasis im Alter von 11-74 Jahren einer Gruppe von 42 Psoriatikern im Alter von 20-49 Jahren gegenübergestellt. Dabei konnte ein wesentlich höherer Befall der gelenknahen Knochenabschnitte nuklearmedizinisch nachgewiesen werden als dies bisher aufgrund der röntgenologischen und klinischen Befunde vermutet wurde. Zusätzlich wurden seit 1977/78 bei 205 Patienten mit Psoriasis Ganzkörperszintigraphien mit 99mTc-Phosphat-Verbindungen angefertigt. Hierbei konnten bei 17 Patienten vermehrte Aktivitätsanreicherungen im Bereich der extraartikulären Knochenabschnitte der Schädelkalotte und des knöchernen Thorax nachgewiesen werden. Nach den vorliegenden Ergebnissen muß angenommen werden, daß neben der klinisch und röntgenologisch definierten Psoriasis-Arthritis bei Psoriatikern eine nur mit Hilfe der Knochenszintigraphie nachweisbare Osteopathie existiert, die sich vorwiegend im Bereich der gelenknahen Knochenabschnitte manifestiert, sich jedoch auch im Bereich der extraartikulären Skelettabschnitte nachweisen läßt und die in ihrer Ausdehnung nur teilweise den röntgenologischen Kriterien der Symmetrie und des Strahlbefalls entspricht.

Procedure guidelines for MIBG-scintigraphy in children

The German translation of the EANM guideline for MIBG scintigraphy in children (Olivier P et al. EJNM MI 2003; 30: B45–B50; Hahn K. Der Nuklearmediziner 2002; 25: 101–105) was reviewed and actualized according to current publications, legal requirements and conditions in Germany. For the first time this guideline was generated in consensus with the neuroblastoma study group of the Association of Paediatric Haematologie and Oncology (GPOH) with the result of an interdisciplinary recommendation. Further main alterations are related to the recommended 123I activities with respect to the new EANM Paediatric Dosage Card and the explicit recommendation of SPECT.

Facile fabrication of mesoporous silica micro-jets with multi-functionalities

Self-propelled micro/nano-devices have been proved as powerful tools in various applications given their capability of both autonomous motion and on-demand task fulfilment. Tubular micro-jets stand out as an important member in the family of self-propelled micro/nano-devices and are widely explored with respect to their fabrication and functionalization. A few methods are currently available for the fabrication of tubular micro-jets, nevertheless there is still a demand to explore the fabrication of tubular micro-jets made of versatile materials and with the capability of multi-functionalization. Here, we present a facile strategy for the fabrication of mesoporous silica micro-jets (MSMJs) for tubular micromotors which can carry out multiple tasks depending on their functionalities. The synthesis of MSMJs does not require the use of any equipment, making it facile and cost-effective for future practical use. The MSMJs can be modified inside, outside or both with different kinds of metal nanoparticles, which provide these micromotors with a possibility of additional properties, such as the anti-bacterial effect by silver nanoparticles, or biochemical sensing based on surface enhanced Raman scattering (SERS) by gold nanoparticles. Because of the high porosity, high surface area and also the easy surface chemistry process, the MSMJs can be employed for the efficient removal of heavy metals in contaminated water, as well as for the controlled and active drug delivery, as two proof-of-concept examples of environmental and biomedical applications, respectively. Therefore, taking into account the new, simple and cheap method of fabrication, highly porous structure, and multiple functionalities, the mesoporous silica based micro-jets can serve as efficient tools for desired applications.

Perceptually accurate display of two greyscale images as a single colour image

Life scientists often desire to display the signal from two different molecular probes as a single colour image, so as to convey information about the probes' relative concentrations as well as their spatial corelationship. Traditionally, such colour images are created through a merge display, where each greyscale signal is assigned to different channels of an RGB colour image. However, human perception of colour and greyscale intensity is not equivalent. Thus, a merged image display conveys to the typical viewer only a subset of the absolute and relative intensity information present in and between two greyscale images. The Commission Internationale de l'Eclairage L*a*b* colour space (CIELAB) has been designed to specify colours according to the perceptually defined quantities of hue (perceived colour) and luminosity (perceived brightness). Here, we use the CIELAB colour space to encode two dimensions of information about two greyscale images within these two perceptual dimensions of a single colour image. We term our method a Perceptually Uniform Projection display and show using biological image examples how these displays convey more information about two greyscale signals than comparable RGB colour space-based techniques.

A High-Resolution Imaging Technique using a Whole-body, Research Photon Counting Detector CT System

A high-resolution (HR) data collection mode has been introduced to the whole-body, research photon-counting-detector CT system installed in our laboratory. In this mode, 64 rows of 0.45 mm × 0.45 mm detectors pixels were used, which corresponded to a pixel size of 0.225 mm × 0.225 mm at the iso-center. Spatial resolution of this HR mode was quantified by measuring the MTF from a scan of a 50 micron wire phantom. An anthropomorphic lung phantom, cadaveric swine lung, temporal bone and heart specimens were scanned using the HR mode, and image quality was subjectively assessed by two experienced radiologists. Comparison of the HR mode images against their energy integrating system (EID) equivalents using comb filters was also performed. High spatial resolution of the HR mode was evidenced by the MTF measurement, with 15 lp/cm and 20 lp/cm at 10% and 2% MTF. Images from anthropomorphic phantom and cadaveric specimens showed clear delineation of small structures, such as lung vessels, lung nodules, temporal bone structures, and coronary arteries. Temporal bone images showed critical anatomy (i.e. stapes superstructure) that was clearly visible in the PCD system but hardly visible with the EID system. These results demonstrated the potential application of this imaging mode in lung, temporal bone, and vascular imaging. Other clinical applications that require high spatial resolution, such as musculoskeletal imaging, may also benefit from this high resolution mode.

Histamine Receptor Expression in the Gastrointestinal Tract of Dogs

Histamine is an important mediator of many physiological processes including gastrointestinal function that acts via four different histamine receptors (H1R to H4R). Elevated histamine levels and increased HR messenger ribonucleic acid (mRNA) have been shown in humans with gastrointestinal disorders such as irritable bowel syndrome or allergic intestinal diseases. As there is limited knowledge concerning the distribution of histamine receptors (HR) in dogs, one aim of this study was to investigate the expression of histamine 1 receptor (H1R), histamine 2 receptor (H2R) and histamine 4 receptor (H4R) in the canine gastrointestinal tract at protein level using immunohistochemistry. Histamine 1 receptor, H2R and H4R were widely expressed throughout the canine gastrointestinal tract including epithelial, mesenchymal, neuronal and immune cells. In addition, in situ hybridisation was established for detecting canine H4R mRNA. Results showed H4R mRNA to be present in enterocytes, lamina propria immune cells and submucosal plexus in the duodenum and colon of nearly all investigated animals. The results elucidate the importance of HR in the canine gut and represent the basis for investigating their possible impact on canine inflammatory gastrointestinal disorders.