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The fibroblast activation protein (FAP) is an emerging target for molecular imaging and therapy in cancer. OncoFAP is a novel small organic ligand for FAP with very high affinity. In this translational study, we establish [Favorable radiochemical properties, rapid clearance from organs and soft tissues, and intense tumor uptake validate

Purpose – The purpose of this paper is to examine the Telenor customer complaints crisis triggered on the company Facebook site in August 2012. More specifically, the paper focusses on how friends and enemies of a company interact, and how faith-holders serve as crisis communicators in a rhetorical sub-arena that opens up on Facebook. Design/methodology/approach – The study is based on a textual analysis of 4,368 posts from the Telenor Facebook site, and an interview with the senior digital manager of Telenor. Findings – Not only current and previous customers but also those from rival telephone companies were active in the Facebook sub-arena. The customers complaining about the company services were met not only with the response of Telenor, but also with counter-attacks from faith-holders acting in defense of Telenor. However, these faith-holders were using defensive response strategies, while Telenor used accommodative strategies. Research limitations/implications – Organizational crises need to be seen as a complex set of communication processes, including the many voices that start communicating from different positions, and taking into account not only the response strategies of the organization but also the response strategies applied by supportive emotional stakeholders. In practice, faith-holders need to be monitored, as they may prove useful as “crisis communicators.” Originality/value – The paper provides insights into an under-investigated area of crisis communication: the strategies of faith-holders acting as “crisis communicators” defending a company and themselves against attacks from negative voices on social media.

Wir stellen den Fall eines 81-jahrigen Patienten mit einem langjahrig bekannten Prostatakarzinom vor. In den letzten Monaten kam es zum biochemischen Rezidiv. Eine 68Ga-PSMA-PET-CT-Untersuchung ergab neben suspekten paravesikalen Lasionen einen auffalligen Nabelbefund. Der Nabel wurde lokal exzidiert und histopathologisch untersucht. Dabei fand sich eine Umbilikalmetastase durch das Prostatakarzinom, ein sog. Sister-Mary-Joseph-Knoten. Nabelmetastasen sind beim Prostatakarzinom eine extreme Raritat; sie sind jedoch klinisch relevant, da sie haufig auf ein fortgeschrittenes Tumorleiden und eine deutlich verschlechterte Prognose hinweisen.

Knocheneigene maligne Tumoren, Tumoren mit sekundarer Knochenbeteiligung sowie benigne Knochenerkrankungen im Kindes- und Jugendalter stellen den behandelnden Arzt oftmals vor grose Herausforderungen hinsichtlich des weiteren Vorgehens. Dieser Artikel adressiert die Knochenszintigrafie als integralen Bestandteil der Diagnostik o.g. Erkrankungen. Neben Indikationen werden altersspezifisch vorbereitende Masnahmen und angepasste Untersuchungsdurchfuhrungen, Befundinterpretation sowie die Strahlenexposition dargestellt. Hierbei wird sowohl auf die planare Szintigrafie als auch auf raumlich aufgeloste Verfahren wie die SPECT bzw. SPECT/CT eingegangen.

We report on the case of an 81-year-old man suffering from prostate cancer for several years. In recent months, PSA levels increased, and

SummaryPurpose: To distinguish between benign and malignant mediastinal lymph nodes in patients with NSCLC by comparing 2D and semiautomated 3D measurements in FDG-PET-CT.Patients, material, methods: FDG-PET-CT was performed in 46 patients prior to therapy. 299 mediastinal lymph-nodes were evaluated independently by two radiologists, both manually and by semi-automatic segmentation software. Longest-axial-diameter (LAD), shortest-axial-diameter (SAD), maximal-3D-diameter, elongation and volume were obtained. FDG-PET-CT and clinical/FDG-PET-CT follow up examinations and/or histology served as the reference standard. Statistical analysis encompassed intra-class-correlation-coefficients and receiver-operator-characteristics-curves (ROC). Results: The standard of reference revealed involvement in 87 (29%) of 299 lymph nodes. Manually and semi-automatically measured 2D parameters (LAD and SAD) showed a good correlation with mean

Die Einfuhrung und Zertifizierung eines Qualitatsmanagement-Systems an einer grosen nuklearmedizinischen Universitatsklinik hat das Potenzial, Arbeitsablaufe besser zu gestalten, Aufgaben in Management und Personalfuhrung systematischer zu gestalten und Mitarbeiter aktiv in Entscheidungsprozesse zu involvieren. Dies fuhrt zu einer Steigerung der Qualitat, zu einer effizienteren Nutzung der Ressourcen und durch Einbindung, Verantwortung und Schulung zu einer hoheren Zufriedenheit bei den Mitarbeitern. Die Zertifizierung dokumentiert nach ausen das gelebte Qualitatsmanagement-System und stellt in einem zunehmend kompetitiven Umfeld einen Wettbewerbsvorteil dar. The implementation of a certified quality management system in a large nuclear medicine department at a university hospital offers the potential to increase work-flow effectiveness, to approach management duties and human resource issues more systematically and to involve members of the staff in decision processes. This results in an increased quality of patient care and a more efficient utilisation of resources. Participation, responsibility and systematic training improve satisfaction with the job. The certificate documents a policy of quality and is a competitive advantage.

Technetium-99 m labelled lipophilic radiopharmaceuticals are well established in documenting the loss of cerebral perfusion in the context of brain death diagnosis. The procedures are non invasive, can easily be applied in intensive care patients and are highly standardized. No cases have been reported in whom a complete loss of cerebral perfusion has been diagnosed with 99 m Tc-ECD or 99 m Tc-HMPAO scintigraphy in whom the diagnosis of brain death has not been confirmed thereafter. Owing to the far reaching consequences of the diagnosis “brain death”, the procedures should only be employed by experienced nuclear medicine physicians.

Summary Purpose: To evaluate single photon emission computed tomography (SPECT) using the amino acid l-3-[123I]-α-methyl tyrosine (IMT) and contrast enhanced magnetic resonance imaging (MRI) as diagnostic tools in primary paediatric brain tumours in respect of non-invasive tumour grading. Patients, materials, methods: 45 children with primary brain tumours were retrospectively evaluated. IMT uptake was quantified as tumour/nontumour- ratio, a 4-value-scale was used to measure gadolinium enhancement on contrast enhanced MRI. Statistical analyses were performed to evaluate IMT uptake and gadolinium enhancement in low (WHO I/II) and high (WHO III/ IV) grade tumours and to disclose a potential relationship of IMT uptake to disruption of blood brain barrier as measured in corresponding MRI scans. Results: IMT uptake above background level was observed in 35 of 45 patients. IMT uptake was slightly higher in high grade tumours but the difference failed to attain statistical significance. Grading of individual tumours was neither possible by IMT SPECT nor by gadolinium enhanced MRI. Conclusion: IMT is accumulated in most brain tumours in children. Tumour grading was not possible using IMT or contrast enhancement as determined by MRI. Neither morphological nor functional imaging can replace histology in paediatric brain tumours.

Combining positron emission tomography (PET) and X-ray computed tomography (CT) with simultaneous acquisition may improve diagnostic accuracy in oncology. Moreover this combination holds considerable promise in radiotherapy. Metabolic information may be used in decision making in radiotherapy and in planning target volumes. Furthermore early evaluation of treatment efficacy becomes possible. New tracers for the assessment of tumour hypoxia or apoptosis in clinical routine are currently being developed. These tracers may yield high relevance in radiotherapy. Hybrid scanners facilitate patient handling and shorten the duration of acquisition. Furthermore fusion accuracy is optimal. Prospective studies have to be conducted to show that the new technology improves patient care in terms of efficiency and quality.

Summary Aim: FDG-PET(/CT) is frequently used in surveillance of Ewing sarcoma (ES) patients. Since ES and PNET (primitive neuroectodermal tumours) may cause peripheral metastases some centers routinely recommend whole body PET acquisition from head to toe what may necessitate repositioning of the patient and thus extending examination time. It is not clear yet whether inclusion of lower leg adds to the diagnostic accuracy of PET scanning, especially in primary tumors of the trunk. Patients, method: 40 patients with ES and PNET of the trunk who were referred for surveillance after primary therapy with complete remission, were evaluated retrospectively: 27 men, 13 women; mean age at diagnosis 16.3 (3–35) years. At the time of diagnosis 28 patients had localized and 12 metastatic disease. Almost all of the patients had undergone a combined chemotherapy with surgery or/and radiotherapy. 156 follow-up PET scans of the legs of these patients were evaluated retrospectively. Results: Only in three (1.9%) of 156 scans a pathologic FDG accumulation was attributed to metastatic disease of the lower extremities. In these cases the observation of metastatic disease in the legs did not alter therapy, since in all three cases a multifocal disease progression was observed. Conclusion: Scanning of the lower legs may be omitted during follow-up in patients in whom the primary tumor was located in the trunk and in whom no clinical signs pointing to metastases in the lower legs are present. This provides a sufficient diagnostic power and a shorter examination time, thus increasing patient comfort and scanner availability.

Purpose: To distinguish between benign and malignant mediastinal lymph nodes in patients with NSCLC by comparing 2D and semi-automated 3D measurements in FDG-PET-CT. Patients, material, methods: FDG-PET-CT was performed in 46 patients prior to therapy. 299 mediastinal lymph-nodes were evaluated independently by two radiologists, both manually and by semi-automatic segmentation software. Longest-axial-diameter (LAD), shortest-axial-diameter (SAD), maximal-3D-diameter, elongation and volume were obtained. FDG-PET-CT and clinical/FDG-PET-CT follow up examinations and/or histology served as the reference standard. Statistical analysis encompassed intra-class-correlation-coefficients and receiver-operator-characteristics-curves (ROC). Results: The standard of reference revealed involvement in 87 (29%) of 299 lymph nodes. Manually and semi-automatically measured 2D parameters (LAD and SAD) showed a good correlation with mean intraclass coefficients of .80 and .72, respectively. Semi-automated prediction revealed the highest areas-under-the-ROC-curve for volume (.75, 95%CI: .69–81) and SAD (.75, 95%CI: .70-.81). AUC for LAD and maximal-3D diameter were about .68. Substantially lower accuracies were found for elongation (.57, 95%CI: .50-.64). Conclusion: Optimized semi-automated three dimensional parameters by CT cannot approximate reported data on FDG-PET-CT for lymph node assessment in NSCLC. SAD remains the most accurate and at the same time simple to achieve anatomical criterion for definition of NSCLC target lesions.

This study evaluated a MDCT protocol for contrast-enhanced 16-channel PET-CT with regard to scan range and duration of a whole-body (18)F-FDG PET-CT examination, the occurrence of contrast-material induced artefacts and quantitative assessment of CT attenuation.205 patients (51.9+/-12.4 years) with different malignant tumours underwent whole-body PET-CT; the study protocol had been approved by the institutional review board. Contrast-enhanced MDCT (16 x 1.5 mm; 120 ml Iomeprol 3 ml/s, 50 ml saline chaser bolus, scan delay 70 s; oral contrast) was also used for attenuation correction. From MDCT data mean scan range and duration, occurrence of contrast media-induced artefacts, and mean CT densities of jugular (jv) and subclavian (scv), superior (vcs) and inferior (vci) caval, portal (pv), and bilateral external iliac veins, pulmonary (ap) and iliac arteries, descending thoracic and abdominal aorta, all cardiac chambers, as well as both liver lobes, spleen, adrenal glands and kidneys were determined.Attenuation corrected PET images were free of contrast media-related image artefacts. Homogeneous contrast enhancement was found in the mediastinal veins (right/left jv 171+/-34/171+/-35, scv 127+/-50/127+/-40, vcs 153+/-36 HU) and arteries (e.g. ap 145+/-26/151+/-26). Cardiac chambers, abdominal vessels (e.g. vci 138+/-24, pv 159+/-25 HU), and parenchymal organs revealed sufficient and homogenous contrast-enhancement in all cases. No beam-hardening artefacts occurred in the neighbourhood of the subclavian veins.The chosen whole-body (18)F-FDG 16-slice PET-CT protocol allowed for craniocaudal CT scanning with high vessel and parenchymal contrast revealing no IV contrast-media induced artefacts in attenuation-corrected PET data sets.

Many aspects have to be considered in planning, applying, and following up radiotherapy procedures. This field poses a major challenge for diagnostic techniques. The first goal in the definition of multimodal oncological therapy concepts is to identify the patients who benefit from a definitive or adjuvant radiotherapy. After the decision for radiotherapy, the sequential process of radiotherapy planning and application has to be initiated. The basic principle is the exploitation of the therapeutic ratio, i.e., obtaining a high tumor dose and maximal protection of the surrounding normal tissue at risk. Computed tomography (CT) is an integral part of radiotherapy planning. Aside from its diagnostic value of tumor and neighboring normal tissue identification, the radiographie density matrix of CT is the basis for calculating the three-dimensional dose distribution. Positron emission tomography (PET) is not yet established as a standard in radio-oncological concept and procedure.

We report the rare case of a 74-year-old man who was admitted to our hospital with rapid progression of tetraparesis, which was most apparent in the lower right limb, sensory disturbances from C3 to S1 on the left side and recent onset of constipation and urinary retention. There was no known history of cancer. As MRI of the neck disclosed a cervical intramedullary mass lesion at C 4/5 level suspicious for a primary glial tumour, the patient underwent surgery. After microsurgical excision the histological analysis of the lesion unexpectedly revealed an intramedullary spinal cord metastasis (ISCM) of a poorly differentiated carcinoma, immunohistochemically consistent with a bronchial carcinoma. As intramedullary spinal cord metastases are generally associated with poor survival, a palliative irradiation of the levels C1-6 was additionally performed. Unfortunately tetraparesis and numbness remained. The very rare occurrence of intramedullary spinal cord metastasis and the absence of pathognomonic symptoms often lead to a delay until an underlying malignancy is discovered. Although rare, intramedullary spinal cord metastasis should be considered as a differential diagnosis of a spinal intramedullary lesion. Surgery and radiation are both options in the controversially discussed treatment of ISCM.

To evaluate the influence of the introduction of combined PET/CT scanners into clinical routine. This investigation addresses the quantitative changes between PET/CT and stand alone PET.The study included all examinations performed on stand alone PET- or PET/CT-scanners within 12 month prior to and after implementation of PET/CT. The final data analysis included five university hospitals and a total number of 15 497 exams. We distinguished exams on stand alone tomographs prior to and after installation of the combined device as well as PET/CT scans particularly with regard to disease entities. Various further parameters were investigated.The overall number of PET scans (PET and PET/CT) rose by 146% while the number of scans performed on stand alone scanners declined by 22%. Only one site registered an increase in stand alone PET. The number of exams for staging in oncology increased by 196% while that of cardiac scans decreased by 35% and the number of scans in neurology rose by 47%. The use of scans for radiotherapy planning increased to 7% of all PET/CT studies. The increase of procedures for so-called classic PET oncology indications was moderate compared to the more common tumors. An even greater increase was observed in some rare entities.The introduction of PET/CT led to more than a doubling of overall PET procedures with a main focus on oncology. Some of the observed changes in scanning frequency may be caused by a rising availability of new radiotracers and advancements of competing imaging methods. Nevertheless the evident increase in the use of PET/CT for the most common tumour types demonstrates its expanding role in cancer staging. The combination of molecular and morphologic imaging has not only found its place but is still gaining greater importance with new developments in technology and radiochemistry.

Aims: Isometric grip force variability (GFV) in Huntington's Disease (HD) was shown to correlate with (1) the severity of motor deficits in HD as assessed in the UHDRS (Gordon et al. 2000), (2) the CAG-repeat length when normalized for age (Reilmann et al. 2004), and (3) the degree of atrophy observed in the caudate nucleus on MRI volumetry (Reilmann et al 2005). Furthermore grip force variability was shown to increase in the course of HD (Reilmann et al. 2001). Objective: To investigate whether GFV in a grasping and holding task is pathologically increased in clinically asymptomatic carriers of the Huntington gene. Subjects and methods: HD gene carriers (n=13) and age-and-sex-matched healthy controls (n=13) were instructed to grasp and lift an object (weight 250g or 500g) in the precision grip and hold it next to a marker 10cm high for 30 seconds. Thirteen trials were performed in each weight condition. Grip and lift forces were recorded using force transducers (Mini-30, ATI, USA). Object position was recorded using a 3D-tracking device (Fastrack, Polhemus, USA). Data was recorded and analyzed using a flexible laboratory computer system (SC/ZOOM, University of Umea, Sweden). Mean grip force and its coefficient of variation were calculated during a 20s period in the static holding phase. Gene carriers were clinically assessed by the UHDRS and exhibited total motor scores

To evaluate single photon emission computed tomography (SPECT) using the amino acid l-3-[123I]-alpha-methyl tyrosine (IMT) and contrast enhanced magnetic resonance imaging (MRI) as diagnostic tools in primary paediatric brain tumours in respect of non-invasive tumour grading. Patients, materials, methods: 45 children with primary brain tumours were retrospectively evaluated. IMT uptake was quantified as tumour/nontumour-ratio, a 4-value-scale was used to measure gadolinium enhancement on contrast enhanced MRI. Statistical analyses were performed to evaluate IMT uptake and gadolinium enhancement in low (WHO I/II) and high (WHO III/IV) grade tumours and to disclose a potential relationship of IMT uptake to disruption of blood brain barrier as measured in corresponding MRI scans.IMT uptake above background level was observed in 35 of 45 patients. IMT uptake was slightly higher in high grade tumours but the difference failed to attain statistical significance. Grading of individual tumours was neither possible by IMT SPECT nor by gadolinium enhanced MRI.IMT is accumulated in most brain tumours in children. Tumour grading was not possible using IMT or contrast enhancement as determined by MRI. Neither morphological nor functional imaging can replace histology in paediatric brain tumours.

Mit nuklearmedizinischen Verfahren lassen sich einerseits die Durchblutung und Beluftung der Lunge darstellen, andererseits kann anhand der Stoffwechselintensitat von Tumoren eine Aussage uber Dignitat und Ausbreitung getroffen werden. Zur Perfusionsdarstellung werden Technetium-markierte Eiweispartikel eingesetzt. Zur Unterscheidung einer primaren Perfusionsstorung (Lungenembolie) von einer sekundaren Perfusionsminderung infolge einer Beluftungsstorung, ist immer auch die Darstellung der Lungenbeluftung mithilfe der Ventilations- bzw. Inhalations-Szintigraphie erforderlich. In Ausnahmefallen ist eine projektionsradiographische Darstellung des Thorax in zwei Ebenen sinnvoll. Ein unauffalliges Lungenperfusions-Szintigramm hat einen hohen negativen pradiktiven Wert hinsichtlich einer Lungenembolie. Der isolierte Perfusionsausfall wenigstens zweier Segmente spricht mit hoher Wahrscheinlichkeit fur eine Lungenembolie. Fur die Ventilationsdarstellung werden Aerosole oder quasi gasformige verdampfte Kohlepartikel eingesetzt. Sowohl Ventilation als auch Perfusion konnen mit der Einzelphotonen-Emissions-Computertomographie (SPECT) uberlagerungsfrei dargestellt werden. Auch fur die Quantifizierung der regionalen Verteilung der Lungenfunktion vor einer Operation findet die nuklearmedizinische Lungenfunktionsdiagnostik Verwendung. Fur die Diagnostik von Lungentumoren hat sich die Positronen-Emissions-Tomographie (PET) unter Verwendung der Fluor-markierten Desoxyglukose (FDG) etabliert. Bei der Beurteilung mediastinaler Lymphknoten weist dieses Verfahren eine hohere Genauigkeit als die Computertomographie auf. Eine therapierelevante Stadienanderung wird auch durch Detektion unerkannter Fernmetastasen erreicht. Der diagnostische Zugewinn durch die PET hat dazu gefuhrt, dass in den meisten europaischen Landern und in den USA dieses Verfahren zwischenzeitlich von den Krankenkassen ubernommen wird. Weitere Tracer fur spezifische Biotargets zielen auf endokrine Entitaten. Dazu zahlen Somatostatinanaloga oder Radiojod. Lernziele: Indikationsstellung zur Lungenperfusions-/-ventilations-Szintigraphie Methoden Einsatz der SPECT Quantifizierung der anteiligen Lungenfunktion diagnostische Kriterien fur eine Lungenembolie Prinzipien der Darstellung von Lungentumoren mit der PET PET zum Staging (mediastinale Lymphknoten-Metastasen, Fernmetastasen) Moglichkeit der Darstellung spezifischer Tumoreigenschaften Korrespondierender Autor: Weckesser M Universitat Munster, Klinik fur Nuklearmedizin, Albert-Schweitzer-Str. 33, 48149, Munster E-Mail: m.weckesser@uni-muenster.de

Combining positron emission tomography (PET) and X-ray computed tomography (CT) with simultaneous acquisition may improve diagnostic accuracy in oncology. Moreover this combination holds considerable promise in radiotherapy. Metabolic information may be used in decision making in radiotherapy and in planning target volumes. Furthermore early evaluation of treatment efficacy becomes possible. New tracers for the assessment of tumour hypoxia or apoptosis in clinical routine are currently being developed. These tracers may yield high relevance in radiotherapy. Hybrid scanners facilitate patient handling and shorten the duration of acquisition. Furthermore fusion accuracy is optimal. Prospective studies have to be conducted to show that the new technology improves patient care in terms of efficiency and quality.

(18)F-FDG-PET (FDG-PET) is established in staging and follow-up of malignant melanoma. The legs are affected in 10-40% at time of diagnosis even if the primary is at the arms and torso. Imaging including the legs may detect distant manifestations but increases duration of the scan by approximately 30 min. We intended to disclose the diagnostic benefit of scanning the legs and to evaluate the therapeutic benefit resulting.In this retrospective analyse 213 consecutive PET studies of 153 patients with suspected or recent malignant melanoma were re-evaluated for metastatic spread by a blinded investigator. Histopathological follow-up was assessed for confirmation.Suspicious findings at the legs were depicted in 53 patients on 76 occasions. 38/53 showed pathologic uptake in the torso as well. In 15/53 patients it was restricted to the legs. One of them had a hitherto unknown, clinically relevant finding that was not apparent in palpation and inspection. In 6 other patients with primary location at the legs a validation of the positive PET findings was not possible up to now.Metastases and local recurrence of malignant melanoma at the legs were found in 41% of women and 27% of men. However, a long scan does not yield relevant additional data. We found isolated new manifestations at the legs in only 1/153 patients. We recommend performing a long scan only in patients with previous melanoma manifestations restricted to the legs. In all other cases a short scan of the torso and proximal thighs is sufficient. This allows a higher number of PET-scans without loss of diagnostic power and a shorter examination time.

Scintigraphy using I-123-iodo-alpha-methyl tyrosine (IMT) is useful in the preoperative characterization of gliomas, in detecting recurrent glioma and in the biological re-evaluation of residual or recurrent tumours. A systematic evaluation of non-parenchymal brain tumours has not yet been performed. The aim of the present study was to evaluate IMT SPECT in the management of intracerebral metastases and lymphomas.IMT uptake was analyzed in 31 patients with 28 metastases of extracerebral solid tumours and 7 cerebral lymphomas. Histology revealed high grade lymphomas, melanomas, and carcinomas of the following origin: lung, unknown primary, breast, colon, renal cell, ovary, vagina, frontal sinus. IMT uptake was quantified as ratio between maximal tumour accumulation and average uptake in the contralateral hemisphere.All tumours except two renal cell and one small cell lung carcinoma metastases accumulated IMT (91%). The highest IMT uptake was found in a metastasis of lung carcinoma. IMT uptake was highly variable and was similar in primary and in recurrent tumours.Significant accumulation of IMT is seen in the majority of tumours, so that this technique might be helpful for the management of cerebral metastases and lymphomas.

Ischemic symptoms in children with Moyamoya syndrome are typically provoked by hyperventilation (HV) and are accompanied by the "re-build-up" phenomenon in EEG. The value of scintigraphic detection of HV-provoked perfusion deficits remains to be elucidated.In seven children with Moyamoya syndrome regional cerebral blood flow was assessed by 99mTc-ethyl-cysteine-dimer (ECD) single photon emission computed tomography (SPECT) after HV and under baseline conditions to identify ischemia prone regions.Regional marked hypoperfusion after HV was found in all patients. Predominant perfusion deficits were detected in the frontal lobes.ECD SPECT is a potential tool for the preoperative evaluation of cerebral hemodynamics and for monitoring angiosurgical therapies in Moyamoya disease.

Epileptogenic foci exhibit disturbed function at the level of the benzodiazepine receptor. The aim of our study was to investigate the incidence of focal reductions of temporal benzodiazepine receptor binding (BRB) as assessed by scintigraphy with 123I-iomazenil in patients with denovo temporal lobe epilepsy (TLE).Forty adult patients (age: 34+/-12 years) with cryptogenic denovo TLE underwent scintigraphy with 123I-iomazenil. In all patients, symptomatic epilepsy was excluded by clinical investigation and MRI. The median duration of TLE was seven months, and the patients had a median of three documented seizures in their history of disease. BRB was quantified in four temporal regions covering the whole temporal lobe. Temporal asymmetry values (ASY) were compared with data determined in 13 age-matched controls yielding Z-scores for global and regional temporal BRB.A significant reduction of temporal BRB was found in 19 of the 40 patients (48 %), mainly in mesial temporal regions; temporal BRB asymmetries were also found in patients with a short history of seizures and low seizure frequency (or = 1 year; n = 32, 13/32 (41 %)). Only in the entire cohort did the magnitude of temporal reduction of BRB correlate with the duration of TLE as well as with the number of previous partial seizures (r = 0.40 and r = 0.36; p0.03, respectively).Foci of decreased BRB can already be detected at the onset of TLE; their magnitude is related to ongoing epileptic activity.

L-3-I-123-iodine-alpha-methyltyrosine (IMT) is a I-123-labelled amino acid which has been used for single photon emission computed tomography (SPECT) of cerebral gliomas for more than a decade. IMT-SPECT is able to detect tumor infiltration independent of disruptions of the blood-brain barrier which is often difficult with computed tomography or magnetic resonance tomography. The method is useful to detect tumor recurrences and helps to distinguish gliomas from non-neoplastic brain masses. IMT-SPECT is thus a valuable tool in the diagnostic evaluation and in therapy planning of patients with cerebral gliomas.

3-[(123)I]Iodo-L-alpha-methyl tyrosine ((123)I-IMT) is used for diagnosis and monitoring of brain tumours by means of single-photon emission tomography. As recently shown, (123)I-IMT is predominantly mediated into rat C6 glioma cells by sodium-independent system L for large neutral amino acids. Until now, (123)I-IMT transport in non-neoplastic glial cells has not been examined. Therefore, the aim of this study was to examine the cellular pathways and precise transport kinetics of (123)I-IMT uptake into astrocytes of neonatal rats. In particular sodium-independent (123)I-IMT transport into neonatal astrocytes was compared with sodium-independent (123)I-IMT uptake into neoplastic rat C6 glioma cells. Competitive inhibition experiments showed that (123)I-IMT is exclusively transported via sodium-independent system L into the neonatal astrocytes (92%). Kinetic analysis of sodium-independent (123)I-IMT uptake into neonatal astrocytes and into C6 glioma cells revealed apparent Michaelis constants K(M) = 13.9 +/- 0.5 microM and K(M) = 33.9 +/- 4.1 microM, respectively, which are in the same range of K(M) values as those recently determined for amino acid transport into neoplastic and non-neoplastic glial cells. Indeed, the K(M) values in the micromolar range correspond to the expression of the LAT-1 subunit of system L both in the neonatal astrocytes and in C6 glioma cells. However, sodium-independent maximum transport velocities (V(max)) differed significantly between neonatal astrocytes and C6 glioma cells (11.1 +/- 0.3 and 39.9 +/- 3.3 nmol/mg protein/10 min, respectively).