Semi-Selective Array for the Classification of Purines with Surface Plasmon Resonance Imaging and Deep Learning Data Analysis

In process analytics or environmental monitoring, the real-time recording of the composition of complex samples over a long period of time presents a great challenge. Promising solutions are label-free techniques such as surface plasmon resonance (SPR) spectroscopy. They are, however, often limited due to poor reversibility of analyte binding. In this work, we introduce how SPR imaging in combination with a semi-selective functional surface and smart data analysis can identify small and chemically similar molecules. Our sensor uses individual functional spots made from different ratios of graphene oxide and reduced graphene oxide, which generate a unique signal pattern depending on the analyte due to different binding affinities. These patterns allow four purine bases to be distinguished after classification using a convolutional neural network (CNN) at concentrations as low as 50 μM. The validation and test set classification accuracies were constant across multiple measurements on multiple sensors using a standard CNN, which promises to serve as a future method for developing online sensors in complex mixtures.

A sub-ppbv-level Acetone and Ethanol Quantum Cascade Laser Based Photoacoustic Sensor - Characterization and Multi-Component Spectra Recording in Synthetic Breath

Trace gas analysis in breath is challenging due to the vast number of different components. We present a highly sensitive quantum cascade laser based photoacoustic setup for breath analysis. Scanning the range between 8263 and 8270 nm with a spectral resolution of 48 pm, we are able to quantify acetone and ethanol within a typical breath matrix containing water and CO₂. We photoacoustically acquired spectra within this region of mid-infra-red light and prove that those spectra do not suffer from non-spectral interferences. The purely additive behavior of a breath sample spectrum was verified by comparing it with the independently acquired single component spectra using Pearson and Spearman correlation coefficients. A previously presented simulation approach is improved and an error attribution study is presented. With a 3σ detection limit of 6.5 ppbv in terms of ethanol and 250 pptv regarding acetone, our system is among the best performing presented so far.

A head coil system with an integrated orbiting transmission point source mechanism for attenuation correction in PET/MRI

The combination of positron emission tomography (PET) and magnetic resonance imaging (MRI) provides a benefit for diagnostic imaging. Still, attenuation correction (AC) is a challenge in PET/MRI compared to stand-alone PET and PET-computed tomography (PET/CT). In the absence of photonic transmission sources, AC in PET/MRI is usually based on retrospective segmentation of MR images or complex additional MR-sequences. However, most methods available today are still challenged by either the incorporation of cortical bone or substantial anatomical variations of subjects. This leads to a bias in quantification of tracer concentration in PET. Therefore, we have developed a fully integrated transmission source system for PET/MRI of the head to enable direct measurement of attenuation coefficients using external positron emitters, which is the reference standard in AC. Based on a setup called the 'liquid drive' presented by Jones et al (1995) two decades ago, we built a head coil system consisting of an MR-compatible hydraulic system driving a point source on a helical path around a 24-channel MR-receiver coil to perform a transmission scan. Sinogram windowing of the moving source allows for post-injection measurements. The prototype was tested in the Siemens Biograph mMR using a homogeneous water phantom and a phantom with air cavities and a Teflon (PTFE) cylinder. The second phantom was measured both with and without emission activity. For both measurements air, water and Teflon were clearly distinguishable and homogeneous regions of the phantom were successfully reproduced in the AC map. For water the linear attenuation coefficient was measured as (0.096  ±  0.005) cm^-1 in accordance with the true physical value. This combined MR head coil and transmission source system is, to our knowledge, the first working example to use an orbiting point source in PET/MRI and may be helpful in providing fully-quantitative PET data in neuro-PET/MRI.

Immediate and delayed neuroendocrine responses to social exclusion in males and females

Social exclusion is a complex phenomenon, with wide-ranging immediate and delayed effects on well-being, hormone levels, brain activation and motivational behavior. Building upon previous work, the current fMRI study investigated affective, endocrine and neural responses to social exclusion in a more naturalistic Cyberball task in 40 males and 40 females. As expected, social exclusion elicited well-documented affective and neural responses, i.e., increased anger and distress, as well as increased exclusion-related activation of the anterior insula, the posterior-medial frontal cortex and the orbitofrontal cortex. Cortisol and testosterone decreased over the course of the experiment, whereas progesterone showed no changes. Hormone levels were not correlated with subjective affect, but they were related to exclusion-induced neural responses. Exclusion-related activation in frontal areas was associated with decreases in cortisol and increases in testosterone until recovery. Given that results were largely independent of sex, the current findings have important implications regarding between-sex vs. within-sex variations and the conceptualization of state vs. trait neuroendocrine functions in social neuroscience.

Ergebnisse der Radiojod-Behandlung von Patienten mit immunogener und nicht-immunogener Hyperthyreose bei Anwendung unterschiedlicher Herddosen

The aim of this study was to check the efficacy of radioiodine (131I) therapy (RIT) in a large number of patients (n = 506) suffering from immunogenic or non-immunogenic hyperthyroidism (Graves’ disease, Plummer’s disease). Since there is no causal cure for immunogenic hyperthyroidism RIT provides, like all other modalities, only a moderate rate of success which is clearly dose-related. Applying 60 Gy, normal thyroid function can be achieved in only 54% of the cases. A dose of 150 Gy succeeds in 86% of the cases. The solitary decompensated autonomous adenoma (DAA) can be eliminated surgically as well as by RIT with a high degree of success (95%). Contrary to surgery, RIT does not have any noticeable early or late morbidity. The high rate of success of RIT in patients with DAA could be confirmed in two groups with different follow-up periods (16 and 65 months). As expected, the rate of hypothyroidism increased from 11 % in the early group to 23% in the late group. Multinodular autonomous adenomas can be eliminated successfully using RIT as well. The concept to apply a dose of 400 Gy to the total functional autonomous tissue as determined by ultrasound yields better results (95%) than 150 Gy to the whole thyroid gland as measured by ultrasound (88%). The rate of hypothyroidism as shown by these results (up to a maximum of 62% after RIT of Graves’ disease using 150 Gy) is the lesser evil compared to remaining or recurrent hyperthyroidism since these patients can be treated with thyroid hormones without problems.

133Xe-DSPECT: Bedeutung der zerebrovaskulären Reservekapazität für Diagnostik und Therapie der chronischen zerebralen Ischämie

Using 133Xe-DSPECT, measurements of regional cerebral blood flow (rCBF) were performed before and after stimulation with 1 g of Diamox® in 55 patients with symptomatic occlusion of the internal carotid artery (ICA) and 26 patients without evidence of brain disease (normals). In normals, a negative correlation (r = -0,74) of the Diamox-induced increase of hemispheric blood flow (reserve capacity) and rCBF at rest was observed. In 48 of the 55 patients (87%) with ICA-occlusion a reduced reserve capacity was found. The extent of reduction, however, did not correlate with the findings of transmission CT, because 15 of 21 patients (71 %) with normal CT-scans presented a moderate to severe reduction of reserve capacity. In contrast, reserve capacity corresponded to the extent of arterial collateralisation as documented by cerebral panangiography. In 31 patients EC/IC-bypass surgery was performed. In follow-up studies reserve capacity increased, especially in patients who had a severe reduction preoperatively. Therefore, the combined measurement of rCBF at rest and of reserve capacity is a sensitive, non-invasive method for the diagnosis of (even bilateral) cerebrovascular disease and can be helpful to identify patients with hemodynamic ischemia, who may benefit from EC/IC-bypass surgery.

Immunoscintigraphy with Anti-225.28S for Ocular Melanoma - a Comparison with Histology and Immunohistochemistry,

Aim: The purpose of this prospective study was to evaluate the value of Immunoscintigraphy (ISG) with anti-225.28S in clinically suspected ocular melanoma. Methods: For this purpose standardized ISG was performed in 36 patients using both planar acquisition and emission computed tomography (ECT). Ocular melanoma was present in 31 patients. In 21 patients therapy was enucleation of the eye. These specimens were evaluated by histology and immunohistochemistry in 11 of 21 patients. Results: Regarding the clinical diagnosis, ISG was positive only in 15 of 31 patients with ocular melanoma, regarding histology in 11 of 21 and regarding immunohistochemistry in 5 of 6 patients with a positive Immunoreaction. 5 patients showed no immunoreactivity, their ISG was negative. Conclusion: Thus a good correlation between ISG and immunohistochemistry was observed. However ISG using the cutaneous melanoma antibody 225.28S cannot be recommanded for the diagnostic work-up of an ocular melanoma considering the poor immunoreactivity.

Highly Sensitive Determination of TSH in the Follow-Up of TSH-Suppressive Therapy of Patients with Differentiated Thyroid Cancer

Basal and TRH-stimulated TSH levels were determined in 72 patients with differentiated thyroid cancer on hormonal treatment, using a highly sensitive immunoradiometric assay (IRMAclon, Henning). 43 patients were under treatment with levothyroxine (T4), 29 patients with triiodothyronine (T3). In 33/43 patients (77%) under T4- and in 18/29 patients (62%) under T3-treatment basal TSH levels were below 0.1 mU/l and levels stimulated with 200 µg TRH i.v. were below 0.5 mU/l. 3 patients showed a significant response (to above 0.5 mU/l) in the TRH test despite basal values of less than 0.1 mU/l. In 2 patients with elevated basal TSH levels (0.23 and 0.60 mU/l, resp.) in the IRMAclon, total suppression of TSH secretion was suggested by a failure of TSH to rise after TRH. By retesting these samples in an own TSH IRMA, basal and stimulated TSH values were below 0.1 mU/l. In conclusion, basal and TRH-stimulated TSH levels are well correlated in most patients with thyroid cancer under hormonal treatment. However, in some cases (5/72) determination of basal TSH could not clearly define the degree of thyrotropic suppression. Thus, TRH testing is still necessary to establish definitely complete TSH suppression in patients with thyroid carcinoma under suppressive treatment.

PET Imaging of Recurrent Medullary Thyroid Cancer

Medullary carcinoma of the thyroid gland is a rare tumor. Its prognosis is mainly linked to surgery, because there is no valid alternative therapy to improve patients outcome. In this report, we discuss the recurrence of such a tumor in a 64-year-old female, focusing on magnetic resonance imaging and positron emission tomography evaluation of this tumor.

Szintigraphie mit111 ln-markiertem Antimyosin bei Churg-Strauss-Vaskulitis mit myokardialer Beteiligung

A case of Churg-Strauss vasculitis in a young woman is reported. Diagnosis was confirmed by muscle biopsy. Affection of lungs, kidneys and skin was evident. In addition, myocarditis was suspected on clinical evidence. A highly positive scintigraphy with 111 In-anti myosin enabled diagnosis and assessment of damage to the myocytes. With a heart-to-lung ratio of 3.0 the accumulated activity in the myocardium was higher than usually found in myocarditis. This finding supports the hypothesis of an additional ischemic necrosis.

133Xe-DSPECT: Normalwerte von zerebraler Ruhedurchblutung und Reservekapazität

Using the 133Xe-DSPECT technique, quantitative measurements of regional cerebral blood flow (rCBF) were performed before and after provocation with acetazolamide (Diamox) i. v. in 32 patients without evidence of brain disease (normals). In 6 cases, additional studies were carried out to establish the time of maximal rCBF increase which was found to be approximately 15 min p. i. 1 g of Diamox increases the rCBF from 58 ±8 at rest to 73±5 ml/100 g/min. A Diamox dose of 2 g (9 cases) causes no further rCBF increase. After plotting the rCBF before provocation (rCBFR) and the Diamox-induced rCBF increase (reserve capacity, Δ rCBF) the regression line was Δ rCBF = −0,6 x rCBFR +50 (correlation coefficient: r = −0,77). In normals with relatively low rCBF values at rest, Diamox increases the reserve capacity much more than in normals with high rCBF values before provocation. It can be expected that this concept of measuring rCBF at rest and the reserve capacity will increase the sensitivity of distinguishing patients with reversible cerebrovascular disease (even bilateral) from normals.

Die Leberperfusions-Szintigraphie: Methodik, Normalwerte und Ergebnisse der Verlaufsbeobachtung von Patienten mit Ösophagusvarizen

Bei 26 Patienten wurde der hepatische Perfusionsindex (HPI) durch einen Vergleich von arteriellem und portalvenösem Anstieg der Zeitaktivitätskurven über der Leber bestimmt. 10 Patienten ohne Anhalt für eine hepatobiliäre Erkrankung (Gruppe A) dienten als Normalkollektiv. Bei 16 Patienten lag eine Leberzirrhose mit Ösophagusvarizen Grad III bis IV vor. Die HPI-Bestimmung erfolgte zweimal im Abstand von 6 Monaten. Bei Gruppe A war HPI mit durchschnittlich 56% signifikant (p <0,001) höher als bei den Patienten mit Leberzirrhose und Ösophagusvarizen (18%). Bei guter »Intra- und Interobserver «-Übereinstimmung (r = 0,96 bzw. 0,92) ist es einer großen intraindividuellen Streuung der Leberdurchblutung zuzuschreiben, daß sich geringe HPI-Änderungen nicht messen lassen. Eine Unterscheidung zwischen normaler portalvenöser Leberdurchblutung und mittel- bis hochgradiger Reduktion ist durch dieses Verfahren sicher möglich.

Erste Ergebnisse der Radioiodtherapie bei multifokaler und disseminierter Autonomie der Schilddrüse unter Verwendung eines TcTUs-adaptierten Dosiskonzepts

Ziel: Die Studie untersucht prospektiv die Wirksamkeit eines an den prätherapeutischen 99mTc-Pertechnetat Uptake der Schilddrüse unter Suppression (TcTUs) angepaßten Dosiskonzeptes zur Radioiodtherapie (RIT) bei Patienten mit multifokaler (MFA) und disseminierter Autonomie (DISA). Dieses Konzept berücksichtigt die gesamte Schilddrüse als Zielvolumen und verwendet Herddosen von 150 Gy bis 300 Gy entsprechend dem TcTUs als Maß für das »autonome Volumen« der Schilddrüse. Methoden: Es wurden 75 Patienten (54 Frauen, 21 Männer; Alter 71 ± 9 Jahre) mit MFA oder DISA ausgewertet. Die Therapie wurde bei Normalwerten für fT3 und fT4 und bei endogener Suppression des TSH durchgeführt. Als Herddosen wurden appliziert: bei einem TcTUs zwischen 1,5-2,5% 150 Gy, bei 2,51-3,5% 200 Gy, bei 3,51-4,5% 250 Gy und bei >4,5% 300 Gy. Die Abschätzung der zu applizierenden Aktivität erfolgte mit einer modifizierten Marinelli-Formel. Als Therapieerfolg galt ein TSH >0,5 mU/l und ein Verschwinden der autonomen Areale im Szintigramm bzw. ein posttherapeutischer TcTU <1,5%. Die mittlere Nachbeobachtungszeit betrug 8 ± 4 Monate. Ergebnisse: Die Erfolgsraten betragen im Durchschnitt 92%. Nur in einem Fall kam es zu einer konsekutiven subklinischen Hypothyreose und in einem weiteren Fall trat eine immunogene Hyperthyreose auf. Schlußfolgerung: Die vorliegenden Daten sprechen dafür, daß auch Patienten mit ausgeprägter Autonomie (TcTUs >3,5%) bei einzeitiger Therapie mit einer Erfolgsrate von über 90% mit dem hier vorgestellten Dosiskonzept behandelt werden können. Die Frühhypothyreoserate ist insgesamt sehr niedrig.

Klinische Wertigkeit der Positronen-Emissions-Tomographie (PET) bei onkologischen Fragestellungen: Ergebnisse einer interdisziplinären Konsensuskonferenz

Ziel: Es ist das Ziel der vorliegenden Arbeit, an Hand bisher publizierter Studienergebnisse eine Beurteilung des klinischen Stellenwertes von PET in der Onkologie zu erarbeiten. Methoden: Im Rahmen einer interdisziplinären Konferenz mit namhaften Experten wurde eine Wertung des gegenwärtigen Stands von PET in der Onkologie an Hand der in der Literatur dokumentierten Studienergebnisse erarbeitet. Angestrebt wurde eine differenzierte Bewertung von PET für die klinische Anwendung in fünf Klassen (1a, 1b, 2a, 2b, 3) von »angemessen« (1a), »akzeptabel« (1b), »hilfreich« (2a), »noch keine Bewertung möglich« (2b), »ohne Nutzen« (3). Ergebnisse: Für den klinischen Einsatz in der Onkologie ist 2-F18-Fluorodeoxyglukose (FDG) das Radiopharmakon der Wahl. PET ist klinisch in der Patientenversorgung zur Rezidivdiagnostik von high-grade Gliomen (FDG), low-grade Gliomen (C-11 Methionin oder F-18 Tyrosin), für die Dignitätsdiagnostik des peripheren Lungenrundherdes bei Risikopatienten sowie für die Diagnostik des Pankreaskarzioms indiziert (Indikation 1a). PET kann in der Patientenversorgung bei folgenden Indikationen (1b) eingesetzt werden: »low-grade« Gliome, Suche nach unbekanntem Primärtumor bei Kopf-Hals-Tumoren, Rezidivdiagnostik des nicht kleinzelligen Bronchialkarzinoms sowie des Rektumkarzinoms, Lymphknotenstaging beim nicht kleinzelligen Bronchial-Karzinom, Pan-kreas-Karzinom, muskelinvasiven Blasen-Karzinom und Hoden-Karzinom. Staging bei M. Hodgkin (Stad. I/II versus III), frühe Therapiekontrolle bei Resttumor und Rezidivdiagnostik bei M. Hodgkin und hochmalignen Non-Hodgkin-Lymphomen, Lymphknoten-Staging und Fern-metastasensuche beim malignen Melanom (Breslow >1,5 mm), Lymphknoten- und Fernmetastasen-Nachweis beim Schilddrüsen-Karzinommit erhöhtem hTg und nicht radiojodspeichernden Metastasen. Zahlreiche weitere Indikationen zeichnen sich bereits jetzt ab, sind jedoch noch weniger gut durch wissenschaftliche Studien belegt. Für die meisten Indikationen außerhalb wissenschaftlicher Studien ist eine individuelle Kosten-Nutzen-Betrachtung durch den verantwortlichen Arzt geboten. Schlußfolgerungen: Die metabolische Bildgebung von PET besitzt für eine Vielzahl onkologischer Fragestellungen prinzipielle Vorteile gegenüber der anatomisch-morphologisch orientierten Schnittbilddiagnostik. Für die klinische Indikationsstellung ist allerdings eine differenzierte Betrachtung der spezifischen Leistungsfähigkeit von PET geboten.

Photopenic Lesions in Bone Marrow Scintigraphy Using Technetium-99m Labeled Antigranulocyte Antibody without Known Tumour

Aim: The purpose of this study was to elucidate the frequency of photopenic lesions in patients without known tumour disease by using bone marrow scintigraphy with Tc-99m labeled anti-NCA-95. Methods: Whole body immunoscintigraphy (IS) was performed in 141 consecutive patients with fever of unknown origin. The age ranged between 20 and 88 years with a mean age of 57 years. None of the patients had known tumour disease. Scans were evaluated with respect to photopenic lesions and to bone marrow distribution. Results: IS showed bone marrow defects in the axial skeleton in 16 patients (11 %). With the help of the typical scintigraphic defect pattern, the cause of the lesions was clearly identified as degenerative changes in four patients and in one patient as due to prior sternotomy. In the remaining 11 patients the origin of the defects became evident when the case history or additional imaging was consulted. The mean age of these 16 patients was 69 years ranging from 50 to 88 years. There was an age-related frequency of defects. 10% of the patients from 50 to 59 years showed defects, 60-69 years 9%, 70-79 years 30%, and 33% of the patients from 80 to 89 years had defects. IS was not hampered by tracer uptake to liver or spleen in 93 patients. Left caudal ribs were obscured in 48 patients with intense tracer uptake to the spleen. No or markedly reduced tracer uptake was found in caput humeri and caput femori in 94 and 82 patients, respectively. Patchy tracer uptake to the bone marrow of the limbs was seen in 13/62 patients showing marrow expansion in the lower limbs and 14/55 with marrow expansion in the upper limbs. The patchy pattern was asymmetric in 12 of these patients. Conclusion: The results of the present study reveal that using Tc-99m NCA-95, photopenic lesions of the bone marrow are rarely seen in patients without known malignant disease. The occurrence of benign lesions is age-related. The benign cause of the lesion was obvious from location and pattern of the lesion in about 30% of the cases. Evaluation of lesions in the upper and lower limbs may be hindered due to physiological variation of marrow distribution. Nevertheless, IS appears to be well-suited for the detection and localization of bone marrow metastases.

Imaging of a Metastatic Gastrointestinal Carcinoid by F-18-DOPA Positron Emission Tomography

The localization of carcinoids in the gastrointestinal tract is frequently difficult if not impossible with the imaging procedures used to date. It is reported on a patient with metastasizing carcinoid in whom various imaging procedures were not successful in detecting the primary tumor. Due to the importance of primary tumor proof for potential curative surgical therapy, a whole-body positron emission tomography with F-18-DOPA was performed. PET enabled localization of a potential primary tumor in the ileum. Moreover, in addition to the known abdominal lymph node and liver metastases, it detected a mediastinal lymph node metastasis and a pulmonary metastasis. F-18-DOPA whole-body PET may be a very promising imaging approach to the localization and staging of gastrointestinal carcinoids.

Precise Localization of Dysfunctional Areas in Vertebrobasilar Infarction by FDGand 0-15-H20-PET Using Standardized Image Analysis and Image Registration to 3-D MR

The advantages of standardized multimodal image analysis are demonstrated in a case of symptomatic tremor after basilar thrombosis. Functionally and structurally lesioned areas were mapped in Talairach space using 3-D MRI, cerebral FDG-PET and 0-15-H20-PET. Structural lesions were found in the left midbrain, thalamus, putamen and cerebellar areas. Voxel-based statistics in comparison to a normal data base revealed hypometabolism in the left thalamus, left red nucleus, left cerebellar hemisphere including dentate nucleus and in the left inferior olivary nucleus. The 0-15-H20-PET investigation revealed metabolic uncoupling along the rubroolivocerebellar loop. Given the delicate anatomy of the structures involved, image registration and standardized image analysis techniques are essential for a synoptic multimodality analysis of morphological and functional pathology and should generally be used for cerebral PET investigations.

Darstellung eines Nebennierenrindenkarzinoms und seiner Metastasen mit FDG-PET

Beschrieben wird der Fall einer jetzt 42jährigen Patientin, die zwei Wochen nach RO-Resektion eines Nebennierenrindenkarzinoms in der Nebennierenloge eine neuerliche ausgedehnte Raumforderung zeigte. Das rasche Wachstum ließ Zweifel an der Diagnose eines Lokalrezidivs aufkommen. In der PET-Untersuchung konnten neben einem großen Lokalrezidiv mehrere Lungen-als auch Lebermetastasen nachgewiesen werden, so daß auf eine operative Sanierung der Lungenfiliae verzichtet wurde. Die FDG-PET erscheint somit geeignet, in einer einzeitigen Untersuchung Nebennierenrindenkarzinome darzustellen und eine Ausbreitungsdiagnostik zu führen.

18F-FDG PET and conventional imaging for assessment of Hodgkin’s disease and non Hodgkin’s lymphoma

The aim of this study was to assess the diagnostic value of FDG-PET and conventional imaging (CI) in a large series of patient with Hodgkin’s disease (HD) or non-Hodgkin’s lymphoma (NHL) at three time points during their course of disease. Patients, methods: 169 consecutive lymphoma patients (69 HD; 100 NHL) were included. 193 FDG-PET studies were performed for staging at baseline in 42 cases, for post-therapeutic monitoring in 103, and for diagnosis of recurrence in 48 cases. Performance indices of sensitivity, specificity, positive (PPV) and negative predictive value (NPV), and accuracy of metabolic FDG-PET and morphological CI were calculated. Differences in staging and diagnosis of residual or recurrent lymphoma were compared. Results: FDG-PET changed staging in 36% of cases for staging at baseline, in 52% of cases for monitoring response to treatment, and in 29% for diagnosis of recurrence. FDG-PET staging results were confirmed in 80% for staging at baseline, in 74% for monitoring response to treatment, and in 50% for diagnosis of recurrence. FDGPET and CI differed significantly at monitoring response to treatment for sensitivity (0.91 versus 0.69; p<0.02), specificity (0.90 versus 0.38; p<0.00001), PPV (0.77 versus 0.42; p<0.001), and accuracy (0.83 versus 0.55; p<0.02). Conclusion: FDG-PET should be considered as the diagnostic modality of choice for post-therapeutic assessment of lymphoma patients and may be a reliable alternative to CI for staging at baseline and diagnosis of recurrence.

Guideline for in vivo- and in vitro procedures for thyroid diseases (version 2)

The version 2 of the guideline for diagnostic standards of thyroid disorders is an update of the guideline published in 1999 and describes standards of in vitro and in vivo procedures. The following statements are modified: In vitro procedures: When measurement of the TSH-receptor antibodies is indicated, the guideline recommends the use of a second generation assay (recombinant human TSH-receptor as antigen). The functional assay sensitivity for the measurement of thyroglobulin should reach a value ≤1 ng/ml. Moleculargenetic tests (RET proto-oncogen) are indicated in patients with a newly diagnosed medullary thyroid cancer and in the relatives of patients with hereditary medullary thyroid cancer. In vivo procedures: The sonographic examination should use a probe with a frequency of at least 7.5 MHz. Indications for the thyroid scintigraphy: nodule size ≥1 cm in diameter, autonomous goitre/nodule with clinical or subclinical hyperthyroidism, necessity of a differentiation between Graves’ disease and chronic lymphocytic thyroiditis, therapy control after a definitive treatment and – in individual cases – the follow-up of untreated autonomous nodules.

Guideline for radioiodine therapy for benign thyroid diseases (version 3)

The version 3 of the guideline for radioiodine therapy for benign thyroid diseases presents first of all a revision of the version 2. The chapter indication for radioiodine therapy, surgical treatment or antithyroid drugs bases on an interdisciplinary consensus. The manifold criteria for decision making consider the entity of thyroid disease (autonomy, Graves’ disease, goitre, goitre recurrence), the thyroid volume, suspicion of malignancy, cystic nodules, risk of surgery and co-morbidity, history of subtotal thyroidectomy, persistent or recurrent thyrotoxicosis caused by Graves’ disease including known risk factors for relapse, compression of the trachea caused by goitre, requirement of direct therapeutic effect as well as the patient’s preference. Because often some of these criteria are relevant, the guideline offers the necessary flexibility for individual decisions. Further topics are patients’ preparation, counseling, dosage concepts, procedural details, results, side effects and follow-up care. The prophylactic use of glucocorticoids during radioiodine therapy in patients without preexisting ophthalmopathy as well as dosage and duration of glucocorticoid medication in patients with preexisting ophthalmopathy need to be clarified in further studies. The pragmatic recommendations for the combined use of radioiodine and glucocorticoids remained unchanged in the 3rd version.

Radioisotope albumin flux measurement of microvascular lung permeability: an independent parameter in acute respiratory failure?

Aim: To evaluate the extent to which single measurements of microvascular lung permeability may be relevant as an additional parameter in a heterogenous clinical patient collective with Acute Lung Injury (ALI) and Acute Respiratory Distress Syndrome (ARDS). Methods: In 36 patients with pneumonia (13), non pneumogenic sepsis (9) or trauma (14) meeting the consensus conference criteria of ALI or ARDS double-isotope protein flux measurements (51Cr erythrocytes as intravascular tracer, Tc-99m human albumin as diffusible tracer) of microvascular lung permeability were performed using the Normalized Slope Index (NSI). The examination was to determine whether there is a relationship between the clinical diagnosis of ALI/ARDS, impaired permeability and clinical parameters, that is the underlying disease, oxygenation, duration of mechanical ventilation and mean pulmonary-artery pressure (PAP). Results: At the time of study, 25 patients presented with increased permeability (NSI > 1 × 10-3 min1) indicating an exudative stage of disease, and 11 patients with normal permeability. The permeability impairment correlated with the underlying disease (p >0.05). With respect to survival, there was a negative correlation to PAP (p <0.01). Apart from that no correlations between the individual parameters were found. Especially no correlation was found between permeability impairment and oxygenation, duration of disease or PAP. Conclusion: In ALI and ARDS, pulmonary capillary permeability is a diagnostic parameter which is independent from clinical variables. Permeability measurement makes a stage classification (exudative versus non exudative phase) of ALI/ARDS possible based on a measurable pathophysiological correlate.

Procedure guidelines for radioiodine therapy of differentiated thyroid cancer (version 2)

The procedure guidelines for radioiodine therapy (RIT) of differentiated thyroid cancer (version 2) are the counterpart to the procedure guidelines for 131I whole-body scintigraphy (version 2) and specify the interdisciplinary guidelines for thyroid cancer of the Deutsche Krebs-gesellschaft and the Deutsche Gesellschaft für Chirurgie concerning the nuclear medicine part. Compared with version 1 facultative options for RIT can be chosen in special cases: ablative RIT for papillary microcarcinoma ≤1 cm, ablative RIT for mixed forms of anaplastic and differentiated thyroid cancer, and RIT in patients with a measurable or increasing thyroglobulin concentration but without detectable metastases by imaging. The description of the pretherapeutic dosimetry now includes the isotopes 123I and 124I as well as a broader range of the activity of 131I. Activities of 2-5 GBq 131I are recommended for the first ablative RIT. If high accumulative activities of 131I are expected, men who have not yet finished their family planning should be advised to the option of sperm cryoconservation. An interdisciplinary consensus is necessary whether the new TNM-classification (UICC, 6th edition, 2002) will lead to modified recommendations for surgical or nuclear medicine therapy, especially for the surgical completeness and for the ablative RIT of pT1 papillary cancer.

PET with 18F-DOPA in the imaging of parathyroid adenoma in patients with primary hyperparathyroidism

Preoperative localization of parathyroid adenomas (PA) can shorten operation time and improve curative rate; it becomes especially important in minimally invasive surgical techniques. Aim of this study was to investigate whether positron emission tomography (PET) with 3-,4-dihydroxy- 6-18F-fluorophenylalanine (18F-DOPA), which showed very promising results in other neuroendocrine tumours, also helps to localize PA. Patients, methods: Eight patients with proven primary hyperparathyroidism were studied preoperatively with PET. Seven also underwent scintigraphy with 99mTc-MIBI and ultrasonography of the neck. All patients were operated and the histological finding was used as a gold standard. Results: All eight patients had a histologically proven PA. None of the PA showed any detectable uptake of 18F-DOPA. However, ultrasonography detected 5/7 PA, scintigraphy detected 3/7 PA. Conclusion: These results suggest that PET with 18F-DOPA is not useful in the detection of PA in patients with primary hyperparathyroidism.

Lymph node staging in extracranial head and neck cancer with FDG PET – appropriate uptake period and size-dependence of the results

Aim: Identification of a rationale for the appropriate uptake period for static clinical extracranial head and neck PET imaging and evaluation of the diagnostic accuracy of such an optimized FDG PET approach for lymph node staging in the head and neck region. Methods: In a subset of 5 patients, kinetic tumour studies were performed in order to identify the cellular activity plateau phase of FDG accumulation for head and neck cancer. Seventy-eight consecutive patients (11 women, 67 men; mean age ± SD: 55 ± 11 years; range, 36-78 years), presenting with histologically proven squamous cell carcinoma and sonographically detected lymph nodes in 86 neck sides, underwent clinically indicated FDG PET imaging. PET results were compared to those derived from histological examinations and follow-up imaging results after 6 months in order to calculate sensitivity and specificity for lymph node staging. Results: FDG kinetics in head and neck cancer indicate that the cellular activity plateau of FDG accumulation is reached after an uptake period of 90 min. Using this protocol metastatic involvement of neck sides with lymph nodes less than 1 cm in diameter was correctly identified with a sensitivity of 71.4% and a specificity of 92.3%. Sensitivity increased with the lymph node diameter (1.1-1.5 cm 83.3%, 1.6-2.0 cm 100%, > 2 cm 88.9%). Conclusion: The appropriate uptake period for static clinical extracranial head and neck PET imaging that allows measurements in the activity plateau phase is about 90 min. FDG PET may add some significant information regarding metastatic spread into regional lymph nodes.

Procedure guidelines for dynamic renal scintigraphy

This procedure guideline describes the procedures for dynamic renal scintigraphy with 99mTc-MAG3, 123I-hippuran and 99mTc-DTPA. Common clinical applications as well as a detailed description of the procedure are given. It also includes explanations and hints concerning the analysis, evaluation, interpretation, and presentation of the findings.

Ergebnisse der Radiojod-Behandlung autonomer Schilddrüsen-Adenome unter Berücksichtigung regionaler Jodkinetik und paranodulärer Speicherung

Bei 110 Patienten mit dekompensiertem autonomen Adenom der Schilddrüse wurde der Erfolg einer Radiojod-Therapie mit unterschiedlicher Herddosis (300 Gy, 400 Gy) überprüft. Zusätzlich wurden die relativen paranodulären Speicherungswerte vor und nach Radio-Therapie in Abhängigkeit von der Therapiedauer verglichen. Bei kurzer Therapiedauer (5-8 Tage) sinkt die paranoduläre Speicherung ab, während sie bei langer Therapiedauer (9-20 Tage) zunimmt. Dadurch ist die bei langer Therapiedauer nachweisbare höhere Hypothyreoserate (14%) erklärbar. Die Ausschaltquote betrug bei einer Herddosis von 300 Gy 93,6%, bei 400 Gy waren es 95%. Dagegen fand sich bei einer Herddosis von 300 Gy eine geringere (3,2%) Hypothyreoseinzidenz als bei 400 Gy (8,8%). Trotzdem sollte zur Verminderung der Versagerquote die höhere Herddosis gewählt werden. Wegen des Ansteigens der Hypothyreoserate mit zunehmender paranodulärer Speicherung empfiehlt sich in Fällen von paranodulären Speicherungswerten zwischen 10 und 20% (sogenannter Übergangstyp) eine exogene Suppression mit Schilddrüsenhormon.

Die Funktionsszintigraphie der Lungenventilation mit 133Xe bei juveniler Skoliose

An 20 Kindern mit ausgeprägter Skoliose wurde vor geplanter Korrekturoperation nach Harrington eine Spirometrie, Röntgenuntersuchung der Lunge sowie eine Lungenfunktionsszintigraphie mit 133Xe durchgeführt. Bei der Szintigraphie wurden prozentuale Verteilung der funktionellen Residualkapazität (FRC) und die Auswaschkurven mit den Parametern: 3-Min.-Retention vor Untergrundkorrektur, der mittleren Zeitkonstante und dem Effektivitätsindex nach Untergrundkorrektur quantitativ ausgewertet. Während die Röntgenbilder sowie die single breath-Phase der Funktionsszintigraphie meist unauffällig blieben, zeigte die Verschiebung der prozentualen FRC-Verteilung zur Konkavseite der Skolioselunge in allen Fällen eine regionale restriktive Ventilationsstörung der Konvexseite an, während die Analyse der Auswaschkurven darüber hinaus ausgeprägte regionale alveoläre Ventilationsstörungen der Konvexseite der Skolioselunge nachwies. Auch in den Fällen, in denen die Spirometrie unauffällig blieb, waren alle Parameter schon gering pathologisch, was am ehesten auf eine schon vorliegende Beeinträchtigung der Lungenfunktion durch die Skoliose zurückzuführen ist. Der Effektivitätsindex, der bei den Auswaschkurven die Atemfrequenz, das Atemzugsvolumen, die funktionelle Residualkapazität und einen Totraumanteil berücksichtigt, erwies sich als der genaueste und empfindlichste Parameter regionaler alveolärer Abatmungsstörungen.

Effects of Obstruction on Single-Kidney Function Clinical and Experimental Results with 131I-Hippurate and 99mTc-DMSA

In 35 patients, renography with 131I-o-hippurate (OIH) and static renal imaging with 99mTc-dimercaptosuccinic acid (DMSA) were used to measure differential renal function (DRF). The results were compared. Depth correction was applied in both methods. In non-obstructed kidneys (19 patients), both methods revealed nearly identical kidney function (r = 0.98). For completely obstructed kidneys (16 patients), OIH gave a significantly better DRF (14 ml/min) than DMSA. This small difference was of no clinical value. Because DMSA is reported to give unreliable results in unilateral obstructed kidneys, the right ureter was ligated in 8 dogs for 10 days and DRF was measured before and after opening an ureteral fistula. The difference in DRF was about 1% and could be accounted for by the amount of urinary radioactivity collected from the pelvic system after the ligature had been opened. Although DMSA appears to give reliable values in determining DRF, even in obstructed kidneys, OIH is preferred since total clearance values and postrenal urinary dynamics can be determined simultaneously.

Guideline for radioiodine therapy for benign thyroid diseases (version 4)

Version 4 of the guideline for radioiodine therapy for benign thyroid diseases includes an interdisciplinary consensus on decision making for antithyroid drugs, surgical treatment and radioiodine therapy. The quantitative description of a specific goiter volume for radioiodine therapy or operation was cancelled. For patients with nodular goiter with or without autonomy, manifold circumstances are in favor of surgery (suspicion on malignancy, large cystic nodules, mediastinal goiter, severe compression of the trachea) or in favor of radioiodine therapy (treatment of autonomy, age of patient, co-morbidity, history of prior subtotal thyroidectomy, profession like teacher, speaker or singer). For patients with Graves' disease, radioiodine therapy or surgery are recommended in the constellation of high risk of relapse (first-line therapy), persistence of hyperthyroidism or relapse of hyperthyroidism. After counseling, the patient gives informed consent to the preferred therapy. The period after radioiodine therapy of benign disorders until conception of at least four months was adapted to the European recommendation.

Procedure guidelines for radioiodine therapy of differentiated thyroid cancer (version 3)

The procedure guideline for radioiodine therapy (RIT) of differentiated thyroid cancer (version 3) is the counterpart to the procedure guideline for 131I whole-body scintigraphy (version 3) and specify the interdisciplinary guideline for thyroid cancer of the Deutsche Krebsgesellschaft concerning the nuclear medicine part. Recommendation for ablative 131I therapy is given for all differentiated thyroid carcinoma (DTC) >1 cm. Regarding DTC ≤1 cm 131I ablation may be helpful in an individual constellation. Preparation for 131I ablation requires low iodine diet for two weeks and TSHstimulation by withdrawal of thyroid hormone medication or by use of recombinant human TSH (rhTSH). The advantages of rhTSH (no symptoms of hypothyroidism, lower blood activity) and the advantages of endogenous TSHstimulation (necessary for 131I-therapy in patients with metastases, higher sensitivity of 131I whole-body scan) are discussed. In most centers standard activities are used for 131I ablation. If pretherapeutic dosimetry is planned, the diagnostic administration of 131I should not exceed 1–10 MBq, alternative tracers are 123I or 124I. The recommendations for contraception and family planning are harmonized with the recommendation of ATA and ETA. Regarding the best possible protection of salivary glands the evidence is insufficient to recommend a specific setting. To minimize the risk of dental caries due to xerostomia patients should use preventive strategies for dental hygiene.

Unexplained high BMD in DXA-scanned patients is generalized throughout the skeleton and characterized by thicker cortical and trabecular bone

Unexplained high bone mineral density (BMD) is a rare condition and the mechanisms responsible are yet to be described in detail. The aim of the study was to identify patients with unexplained high BMD from a local DXA database and compare their radiological phenotype with an age- and a gender-matched group of population-based controls. We defined high BMD as a DXA Z-score ≥ + 2.5 at the total hip and lumbar spine. We characterized the findings as "unexplained" if no osteodegenerative changes, bone metabolic disease, or arthritis at the hip or lumbar spine was observed. All participants were investigated with high-resolution peripheral quantitative computed tomography (HR-pQCT), QCT, DXA, fasting blood samples, a 24-h urine sample, and questionnaires. The DXA database contained data on 25,118 patients. Initially, 138 (0.55%) potential participants with high BMD were identified, and during the study ten additional cases were identified from new DXA scans. Sixty-seven patients accepted to participate in the study, and among these we identified 15 women and one man with unexplained high BMD. These 15 women had higher BMD throughout the skeleton relative to controls, similar area/volume at the hip and the distal extremities, a higher number of trabeculae, which was thicker than in the controls, and a higher finite element estimated bone strength. The 15 women were heavier and had a higher fat mass then controls. We conclude that patients with unexplained high BMD have a generalized high BMD phenotype throughout their skeleton, which is characterized with a denser microarchitecture.

Twin-twin transfusion syndrome as a possible risk factor for the development of retinopathy of prematurity

PURPOSE

The objective of this study was to evaluate the correlation between twin-twin transfusion syndrome (TTTS) and the development of retinopathy of prematurity (ROP) in premature infants.

METHODS

Fifty-one infants who were less than 32 postmenstrual gestational weeks at birth or with a birth weight less than 1,501grams were included in this longitudinal observational study. The infants were matched by gestational age and birth weight, and divided into three groups: multiples with TTTS, multiples without TTTS, and singletons. The primary outcome variable was the incidence of ROP in infants affected by TTTS versus infants not affected by TTTS. Secondary outcome variables were multiple pregnancy, gestational age, and birth weight.

RESULTS

Infants affected by TTTS showed a significantly higher incidence of ROP than infants not affected by TTTS (p < 0.01). TTTS donors and TTTS recipients were both at greater risk of developing ROP. ROP occurred in infants with TTTS whose gestational age at birth was significantly higher than that of infants with ROP who were not affected by TTTS (p = 0.01). Multiple pregnancy itself was not a risk factor for ROP disease.

CONCLUSIONS

Infants affected by TTTS during pregnancy are at high risk of developing ROP, even if they were born at an older gestational age. Special awareness in ROP screening is necessary for these infants.

Long-term follow-up in patients with CCFDN syndrome

OBJECTIVE

We describe the 10-year follow-up in a cohort of 16 patients with genetically confirmed congenital cataracts, facial dysmorphism, and neuropathy (CCFDN) syndrome, providing new insights in the clinical course of the disease.

METHODS

We performed a detailed clinical and paraclinical characterization and 10-year follow-up study in 16 patients with molecularly defined CCFDN syndrome, illustrating that CCFDN is a severe disabling disorder.

RESULTS

All patients initially presented with congenital cataracts along with strabismus, facial dysmorphism, short stature, and demyelinating neuropathy. In all patients, paresis of small hand muscles and foot extensors worsened with disease progression, while ataxia scores remained stable or improved. Nerve conduction velocity was normal in early infancy up to 18 months, decreased to approximately 20 m/s around age 10 years, and then remained stable; distal motor latency was prolonged. Sensory nerve conduction velocities were slowed, and initially of normal amplitude. With disease progression, both sensory and motor nerves showed reduction of amplitudes indicating axonal loss. In 6 patients, acute severe proximal weakness and myalgia after febrile infections, along with rhabdomyolysis, myoglobinuria, and hyperCKemia, led to a less favorable outcome and permanent loss of ambulation in 3 patients.

CONCLUSIONS

CCFDN should be classified as a recessive demyelinating sensory-motor neuropathy, and axonal loss is a major determinant of long-term outcomes and disability. Patients benefit from early and ongoing physiotherapy, and should be thoroughly counseled regarding virus-triggered rhabdomyolysis and the risk of malignant hyperthermia. Whether supplementation with liposoluble vitamins results in a therapeutic benefit should be evaluated in further studies.

FDG-PET imaging for the staging and follow-up of small cell lung cancer

The staging procedures for small cell lung cancer do not differ appreciably from those for other forms of lung cancer. For practical purposes, the TNM stages are usually collapsed into a simple binary classification: limited disease and extensive disease. This study was performed to answer the question of whether fluorine-18 labelled 2-deoxy-2-D-glucose positron emission tomography (FDG-PET) imaging permits appropriate work-up (including both primary and follow-up staging) of patients presenting with small cell lung cancer, as compared with currently recommended staging procedures. Thirty-six FDG-PET examinations were performed in 30 patients with histologically proven small cell lung cancer. Twenty-four patients were examined for primary staging while four were imaged for therapy follow-up only. Two patients underwent both primary staging and up to four examinations for therapy follow-up. Static PET imaging was performed according to a standard protocol. Image reconstruction was based on an ordered subset expectation maximization algorithm including post-injection segmented attenuation correction. Results of FDG-PET were compared with those of the sum of other staging procedures. Identical results from FDG-PET and the sum of the other staging procedures were obtained in 23 of 36 examinations (6x limited disease, 12x extensive disease, 5x no evidence of disease). In contrast to the results of conventional staging, FDG-PET indicated extensive disease resulting in an up-staging in seven patients. In one patient in whom there was no evidence for tumour on conventional investigations following treatment, FDG-PET was suggestive of residual viability of the primary tumour. Furthermore, discordant results were observed in five patients with respect to lung, bone, liver and adrenal gland findings, although in these cases the results did not affect staging as limited or extensive disease. Moreover, FDG-PET appeared to be more sensitive for the detection of metastatic mediastinal and hilar lymph nodes and bone metastases. Finally, all findings considered suspicious for tumour involvement on the other staging procedures were also detected by FDG-PET. It is concluded that FDG-PET has potential for use as a simplified staging tool for small cell lung cancer.

Usefulness of losartan on the size of the ascending aorta in an unselected cohort of children, adolescents, and young adults with Marfan syndrome

Since 2008, when angiotensin II type I receptor blockade with losartan was introduced in the prevention of cardiovascular manifestation of Marfan syndrome (MFS), a specific treatment to address the cardiovascular lesions became available. The present study aimed to compare the response of such in an unselected cohort of patients with genotyped MFS. At a tertiary university children's hospital, 20 pediatric and adolescent patients aged 1.7 to 21.6 years with genetically proven MFS were enrolled in a prospective treatment study of losartan for evaluation of the aortic dimensions and elasticity indexes. The mean follow-up period was 33 ± 11 months. A significant reduction in the normalized aortic dimensions with losartan was observed in the valve, root, sinotubular junction, and ascending aortic segments (p = 0.008, p <0.001, p = 0.012, and p = 0.001, respectively). No correlation between elasticity behavior and the decrease in the aortic dimension with losartan therapy was detectable. A significant correlation between stronger improvement and younger age at onset (r = 0.643, p = 0.002) and a longer therapy duration (r = -0.532, p = 0.016) was verifiable. However, no correlation between improvement with therapy and the type of mutation or presentation of clinical forms was remarkable. Elasticity also seemed to improve but not significantly. In conclusion, in our cohort of young patients with MFS, a significant improvement with losartan monotherapy was proved in all affected proximal aortic segments, with a better response to therapy when started at an earlier age and with a longer therapy duration.