Resonant metasurfaces at oblique incidence: interplay of order and disorder.

Understanding the impact of order and disorder is of fundamental importance to perceive and to appreciate the functionality of modern photonic metasurfaces. Metasurfaces with disordered and amorphous inner arrangements promise to mitigate problems that arise for their counterparts with strictly periodic lattices of elementary unit cells such as, e.g., spatial dispersion, and allows the use of fabrication techniques that are suitable for large scale and cheap fabrication of metasurfaces. In this study, we analytically, numerically and experimentally investigate metasurfaces with different lattice arrangements and uncover the influence of lattice disorder on their electromagnetic properties. The considered metasurfaces are composed of metal-dielectric-metal elements that sustain both electric and magnetic resonances. Emphasis is placed on understanding the effect of the transition of the lattice symmetry from a periodic to an amorphous state and on studying oblique illumination. For this scenario, we develop a powerful analytical model that yields, for the first time, an adequate description of the scattering properties of amorphous metasurfaces, paving the way for their integration into future applications.

BLADE sequences in sagittal T2-weighted MR imaging of the cervical spine and spinal cord--lesion detection and clinical value.

PURPOSE: Using the BLADE (PROPELLER) technique for T2-weighted MR imaging of the cervical spine has proven to be a reliable tool for reducing artifacts typically for this region. The aim of this study was to evaluate whether the application of BLADE sequences has an impact on the detection of small or low contrast spinal cord and epidural lesions. MATERIALS AND METHODS: A standard TSE and a BLADE sequence were compared in 33 patients with 46 spinal cord and epidural lesions for T2-weighted sagittal imaging of the cervical spine. Image sharpness, visualization of the dura, reliability of spinal cord depiction as well as lesion contrast were evaluated by two independent readers. Additionally two experienced neuroradiologists selected in consensus the sequence they would prefer for diagnostic purposes. Statistical evaluations were performed using the sign and the χ2 test. RESULTS: BLADE was significantly superior to TSE regarding image sharpness, visualization of the dura and reliability of spinal cord depiction. Regarding lesion contrast there was a positive trend towards the BLADE sequence. In 17 of 46 lesions, BLADE was judged superior to TSE, while TSE was favored in 10 lesions. In consensus reading both neuroradiologists preferred BLADE for overall image quality in 27 of 33 patients and for lesion contrast in 10 and TSE in 14 of the 33 patients, but 3 TSE sequences were rated as non-diagnostic regarding this criterion. CONCLUSION: For the detection of even small and low-contrast spinal cord lesions, BLADE is at least equivalent to TSE, yielding better overall image quality and fewer non-diagnostic images.

What limits tool use in nonhuman primates? Insights from tufted capuchin monkeys (Sapajus spp.) and chimpanzees (Pan troglodytes) aligning three-dimensional objects to a surface.

Perceptuomotor functions that support using hand tools can be examined in other manipulation tasks, such as alignment of objects to surfaces. We examined tufted capuchin monkeys' and chimpanzees' performance at aligning objects to surfaces while managing one or two spatial relations to do so. We presented six subjects of each species with a single stick to place into a groove, two sticks of equal length to place into two grooves, or two sticks joined as a T to place into a T-shaped groove. Tufted capuchins and chimpanzees performed equivalently on these tasks, aligning the straight stick to within 22.5° of parallel to the groove in approximately half of their attempts to place it, and taking more attempts to place the T stick than two straight sticks. The findings provide strong evidence that tufted capuchins and chimpanzees do not reliably align even one prominent axial feature of an object to a surface, and that managing two concurrent allocentric spatial relations in an alignment problem is significantly more challenging to them than managing two sequential relations. In contrast, humans from 2 years of age display very different perceptuomotor abilities in a similar task: they align sticks to a groove reliably on each attempt, and they readily manage two allocentric spatial relations concurrently. Limitations in aligning objects and in managing two or more relations at a time significantly constrain how nonhuman primates can use hand tools.

[Perfusion brain imaging with SPECT-technique. German Guideline S1]. / Hirnperfusions-SPECT mit 99mTc-Radiopharmaka. DGN-Handlungsempfehlung (S1-Leitlinie).

This paper describes the guideline for perfusion brain imaging with SPECT-technique published by the Association of the Scientific Medical Societies in Germany (AWMF).The purpose of this guideline is to provide practical assistance for indication, examination procedures, findings and their interpretation also reflecting the present state of the art. Information and instruction are given regarding indication, preparation of the patients and examination procedures of brain perfusion SPECT, including preparation and quality control of the tracer as well as the radiation dosimetry, technical performance of image acquisition with the gamma-camera and image processing. Also advices for interpretation of findings are given. In addition, possible pitfalls are described.

Observations on the effects of inhaled isoflurane in long-term sedation of critically Ill children using a modified AnaConDa©-system.

Long-term intravenous sedation may present problems due to dependence and side effects. Medical records of children who were administered isoflurane were reviewed. 15 patients (9 boys, 6 girls) with a mean age of 11.8 month (+2.4) were analysed.Analgesia and sedation was given in mean 9.7+1.1 days before commencing inhalation using a modified application device (AnaConDa©). Administration was given over a period of 7.2+1.4 days. Depth of sedation was monitored by using Comfort- and Hartwig-scores. Observations included continuous monitoring of heart-rate, pulse oxymetry, blood pressure and cerebral tissue oxygenation.Within 4 h post administration of isoflurane a satisfactory increase in the depth of sedation was seen and kept till extubation. 6/15 patients received tracheostomies during the observation period. None of the patients observed suffered life-critical events of the modified application of isoflurane proceeded without complications. Ketamine and clonidine infusion rates were significantly reduced (p<0.005) as well as the use and overall infusion rate of midazolam, γ-hydroxy butyrate, fentanyl and morphine (p<0.05).Isoflurane inhalation may provide an additional option for long-term sedation in a specific group of critically ill infants but neurodegenerative toxic effects will have to be taken into account when using volatile anesthetics at any time during infancy.

Characterization of microvascularization of liver tumor lesions with high resolution linear ultrasound and contrast enhanced ultrasound (CEUS) during surgery: First results.

AIM: Evaluation of high resolution linear ultrasound and intra-operative linear contrast enhanced ultrasound (CEUS) and its benefit for the detection and characterization of tumor lesions. MATERIAL AND METHODS: Twenty patients were investigated preoperatively regarding tumor detection using CT (n = 8) or MRI (n = 12) and image fusion (VNav) (n = 3). All patients had surgery for their hepatic tumor (hepatocellular carcinoma (HCC), cholangiocellular carcinoma (CCC), metastasis, and adenoma). Ultrasound was performed intra-operatively first with B-scan using a convex probe. Than multifrequency linear transmitters (6-9 MHz, 6-15 MHz, LOGIQ E9, GE) were applied for B-scan, coulor coded Doppler sonography (CCDS) and Power Doppler followed by dynamic CEUS with Contrast Harmonic Imaging (CHI) after bolus injection of a maximum of 15 mL SonoVue®. RESULTS: In 9 cases with the use of intra-operative CEUS additional tumor lesions (diameter 4-15 mm) could be detected and were histologically confirmed after surgical resection (7 cases) or intra-operative biopsy (2 cases). Using intraoperative CEUS 64 tumor lesions could be detected compared to 51 tumor lesions detected by preoperative CT or MRI (p < 0.05). Using the 6-15 MHz multifrequency linear transducer with CHI, arterial perfusion of adenomas, neuroendocrine metastases and HCC lesions was detectable. In 3 cases a resection was not achievable. Two of these cases were treated with radio frequency ablation (RFA). The other case had no curable option due to multifocal tumor manifestation. CONCLUSION: The intra-operative use of high-resolution linear transducer techniques with CEUS offers new diagnostic perspectives for an effective liver surgery.

Asymmetric transmission of linearly polarized light at optical metamaterials.

We experimentally demonstrate a three-dimensional chiral optical metamaterial that exhibits an asymmetric transmission for forwardly and backwardly propagating linearly polarized light. The observation of this novel effect requires a metamaterial composed of three-dimensional chiral meta-atoms without any rotational symmetry. Our analysis is supported by a systematic investigation of the transmission matrices for arbitrarily complex, generally lossy media that allows deriving a simple criterion for asymmetric transmission in an arbitrary polarization base. Contrary to physical intuition, in general the polarization eigenstates in such three-dimensional and low-symmetry metamaterials do not obey fixed relations and the associated transmission matrices cannot be symmetrized.

Understanding the electric and magnetic response of isolated metaatoms by means of a multipolar field decomposition.

We introduce a technique to decompose the scattered near field of two-dimensional arbitrary metaatoms into its multipole contributions. To this end we expand the scattered field upon plane wave illumination into cylindrical harmonics as known from Mie's theory. By relating these cylindrical harmonics to the field radiated by Cartesian multipoles, the contribution of the lowest order electric and magnetic multipoles can be identified. Revealing these multipoles is essential for the design of metamaterials because they largely determine the character of light propagation. In particular, having this information at hand it is straightforward to distinguish between effects that result either from the arrangement of the metaatoms or from their particular design.

Population dynamics of caterpillars on three cover crops before sowing cotton in Mato Grosso (Brazil).

Direct seeding mulch-based cropping systems under a preliminary cover crop such as millet are common in some areas of Brazil. Lepidopteran pests that damage cotton, soybean and maize crops can proliferate on cover crops, so preventive chemical treatments are necessary. Very little data is available on these pests on cover crops. This paper presents the dynamics of Spodoptera frugiperda, S. eridania, Mocis latipes and Diatraea saccharalis caterpillars monitored at Primavera do Leste, Mato Grosso state (Brazil) during the of 2005/2006 and 2006/2007 cropping seasons on four cover crops, i.e. finger millet (Eleusine coracana), pearl millet (Pennisetum glaucum), sorghum (Sorghum bicolor) and ruzigrass (Brachiaria ruziziensis). The pests were visually counted on plants within a 1 m2 transect (wooden frame). Caterpillars were reared to facilitate identification of collected species and parasitoids. Many S. frugiperda caterpillars were observed on millet in 2005, with a maximum of 37 caterpillars/m2. On sorghum, we found 30 caterpillars/m2, or 0.83 caterpillars/plant. The Diatraea borer attacked sorghum later than the other pests. M. latipes was also observed on millet. The millet cover crop had to be dried for at least 1 month before direct drilling the main cotton crop in order to impede S. frugiperda infestations on cotton plantlets, thus avoiding the need for substantial resowing. The comparative methodological aspects are discussed.

[Characterization and management of incidentally detected solitary pulmonary nodules]. / Charakterisierung und Management inzidentell diagnostizierter solitärer Lungenrundherde.

How to deal with solitary pulmonary nodules (SPN) which are incidentally detected by computed tomography (CT) is an increasingly important task in the era of modern multislice CT. This paper reviews the morphological and functional characteristics and their value for discrimination between benign and malignant SPNs. In particular, the importance of nodule size, growth rate, margin morphology, density, calcifications or fatty components within the nodules, the significance of cavitations or aerobronchograms, enhancement patterns at dynamic contrast-enhanced CT and findings on positron emission tomography (PET) are discussed. The Bayesian analysis to calculate the probability of malignancy is presented. Finally, flow charts demonstrate the national and international recommendations for nodule management.

BLADE in sagittal T2-weighted MR imaging of the cervical spine.

BACKGROUND AND PURPOSE: Image quality and diagnostic reliability of T2-weighted MR images of the cervical spine are often impaired by several kinds of artifacts, even in cooperative patients. The aim of this study was to evaluate if BLADE sequences might solve these problems in a routine patient collective. MATERIALS AND METHODS: TSE and BLADE sequences were compared in 60 patients for T2-weighted sagittal imaging of the cervical spine. Image sharpness, motion artifacts, truncation artifacts, metal artifacts, CSF flow phenomena, contrast of anatomic structures (vertebral body/disk, spinal cord/CSF), and diagnostic reliability of spinal cord depiction were evaluated by 2 independent readers. Another 2 readers selected the sequence they would prefer for diagnostic purposes. Statistical evaluations were performed by using the Wilcoxon and the chi(2) test; differences with P < .05 were regarded as statistically significant. RESULTS: BLADE was significantly superior to TSE regarding image sharpness, image contrast, diagnostic reliability of spinal cord depiction, motion artifacts, CSF flow phenomena, and truncation artifacts; for metal artifacts no significant improvements were found. In 50 of 60 patients, BLADE was preferred for diagnostic purposes, and TSE was favored in 3 patients. The number of examinations that were nondiagnostic due to impaired spinal cord depiction was reduced from 12 in TSE to 3 in BLADE, and nondiagnostic examinations due to overall motion artifacts were reduced from 2 to 1. CONCLUSIONS: Using the BLADE sequence for sagittal T2-weighted imaging of the cervical spine proved to be advantageous to reduce various kinds of artifacts.

[Tissue engineering of bone tissue. Principles and clinical applications]. / Tissue Engineering von Knochengewebe: Prinzipien und klinische Anwendungsmöglichkeiten.

Complex fractures are still a major clinical challenge. The treatment options of large bony defects either with autografts or allografts are limited in terms of material availability and tissue in-growth. Tissue engineering might offer a solution to this problem. In an interdisciplinary approach artificial bony tissue can be generated which mimics normal bone in terms of function and morphology. So far tissue engineering of bone is mainly confined to laboratory investigations whereas clinical applications are still in the beginning. This manuscript presents the most important scaffolds as well as growth factors and cell systems. Furthermore, it focuses on clinical studies for the treatment of large bony defects using tissue engineered cell-matrix constructs.

New real-time image fusion technique for characterization of tumor vascularisation and tumor perfusion of liver tumors with contrast-enhanced ultrasound, spiral CT or MRI: first results.

AIM: Evaluation and characterization of the vascularisation and perfusion of liver tumors by means of image fusion of dynamic contrast-enhanced ultrasound (CEUS), multidetector-CT (MD-CT) or magnetic resonance imaging (MRI) with the ultrasound navigation technique. MATERIAL: For interventional planning a real-time image fusion involving CEUS (LOGIQ E9, GE) was performed in 20 patients (12 men, 8 women, age 43-69 years, median 54) with histologically confirmed malignant liver tumors (9 x hepatocellular carcinoma (HCC), 5 x metastases, 2 x hemangiomas, 1 x cholangiocellular carcinoma (CCC), 1 x lymphoma, 1 x neuroendocrine tumor, 1 x focal nodular hypoplasia (FNH)). In 17 patients the real-time CEUS was fused with contrast-enhanced MD-CT and in three patients with contrast-enhanced MRI (Gd-DTPA and liver-specific contrast medium Resovist. All of the ultrasound examinations were performed by an experienced examiner with a multi-frequency probe (2-5 MHz, LOGIQ E9, GE); dynamic image sequences up to 3 minutes in true agent detection mode of contrast harmonic imaging (CHI) were documented. An evaluation of the tumor was performed by the characterization of the dynamics of the contrast medium and microperfusion with CEUS, fused with MD-CT or MRI. RESULTS: In 18/20 cases there was an accurate agreement with respect to the segmental localization of the tumor lesion. In 2/20 cases the localization was comparable with the image fusion of CEUS and reference imaging (a total of at least 65 lesions: 3 x 1 lesion, 5 x 2 lesions, 8 x 3 lesions, 2 x 5 lesions, 1 x 8 lesions, 1 x at least 10 lesions (multifocal)). With image fusion a certain characterization was attained in 17/20 cases. In 3/20 cases (lymphoma after liver transplantation, multifocal CCC, metastases of a neuroendocrine tumor) the diagnosis was at first doubtful and had to be confirmed histologically. In patients with HCC an evaluation of the tumor perfusion was feasible in all 9 cases (8/9 after local trans-arterial chemoembolization (TACE), 1/9 after radio frequency ablation (RFA)). A tendency toward the identification of more lesions with image fusion of CEUS and CT than with contrast-enhanced CT alone could be recognized (p=0.059). CONCLUSION: Applying a new real-time fusion technique of MD-CT or MRI with CEUS new possibilities for the evaluation, intervention and monitoring of the therapy of liver lesions were made possible, since the method also comprised the dynamic microperfusion.

Polarization-independent negative-index metamaterial in the near infrared.

We present and evaluate theoretically and experimentally a design for a negative-index metamaterial that is termed the "Swiss cross" structure. Compared with the established fishnet structure, the proposed design eliminates the drawback of polarization-dependent effective optical parameters. The new design is fabricated by means of e-beam technology and experimentally analyzed using spectroscopic techniques. The thorough comparison with numerical simulations reveals an effective refractive index of n=-1.9 at an operational wavelength of 1400 nm that is independent of the incident polarization. The resonances of the system are comprehensively discussed.

Neoadjuvant bevacizumab, docetaxel and capecitabine combination therapy for HER2/neu-negative invasive breast cancer: Efficacy and safety in a phase II pilot study.

PURPOSE: To evaluate the triplet combination of bevacizumab, capecitabine and docetaxel (XTA) as neoadjuvant therapy for breast cancer. EXPERIMENTAL DESIGN: Patients with invasive, HER2-negative, nonmetastatic breast cancer (T2-4c >2cm) and no prior systemic therapy received six 21-day cycles of XTA (bevacizumab 15mg/kg, day 1, cycles 1-5; docetaxel 75mg/m(2), day 1 of each cycle; capecitabine 950mg/m(2) twice daily for 14 days of each cycle). Patients underwent surgery 2-4 weeks after completing XTA, followed by radiotherapy, chemotherapy and hormone therapy according to institution guidelines. Pathologic complete response (pCR), the primary endpoint, was defined as no evidence of invasive tumour in the final surgical sample. Secondary endpoints included rates of clinical response and breast-conserving surgery and safety. RESULTS: Median age of the 18 enrolled patients was 48 years (range 34-69). Most patients (72%) received six cycles of neoadjuvant therapy. pCR rate was 22% (95% confidence interval [CI]: 6-48). Nine of the patients without pCR achieved clinical partial response, giving a 72% overall clinical response rate (95% CI: 47-90). Fifteen patients underwent breast-conserving surgery (83%; 95% CI: 59-96). One additional patient had breast-conserving surgery, followed by mastectomy 1 month later. The remaining 2 patients underwent modified radical mastectomy. XTA was reasonably well tolerated, with no unexpected toxicities or treatment-related deaths. CONCLUSIONS: The 22% pCR rate in a HER2-negative population suggests that addition of bevacizumab increases the activity of neoadjuvant capecitabine-docetaxel. Further evaluation of this regimen in early breast cancer is recommended.

Pre-surgical evaluation of ICA-stenosis using 3D power Doppler, 3D color coded Doppler sonography, 3D B-flow and contrast enhanced B-flow in correlation to CTA/MRA: first clinical results.

AIM: Pre-surgical evaluation of the extent of internal carotid artery stenosis (ICA) according to NASCT criteria using digital 3D ultrasound methods. MATERIAL/METHODS: In a prospective study, 25 patients (54-88 years, mean 75) with neurological deficits and the diagnosis of ICA stenosis underwent pre-surgical ultrasound examination using Color Coded Duplex Sonography (CCDS), 3D CCDS, 3D power Doppler, 3D B-flow, contrast enhanced 3D B-flow, and CTA/MRA. Ultrasound was performed by an experienced examiner with a multifrequency linear transducer (6-9 MHz, Logiq 9, GE). After bolus injection of 2.4 ml Sonovue i.v., low mechanical index technique (MI<0.16) was used for contrast enhanced 3D B-flow. As reference method for evaluation of the extent of ICA stenosis each patient underwent CTA (multislice CT, Sensation 16, Siemens) and/or MRA (1.5 T, Symphony Siemens). Indications for surgery (carotid EEA) followed the NASCET criteria. All images were interpreted and evaluated independently by two observers with three measurements of the degree of the ICA stenosis. For assessment of the extent of stenosis a 10%-scale from 50% to 99% was used. Statistical analysis was performed using Spearman Correlation and Wilcoxon Signed Rank Test with a significance threshold of p<0.05. RESULTS: Assessment of the extent of ICA stenosis during surgery and in CTA/MRA displayed a range from 60% to 99% (mean 80%). Non significant differences were found with paired Wilcoxon test only for 3D B-flow with and without contrast medium (p<0.05). Correlation with surgical evaluation regarding the extent of ICA stenosis using Spearman correlation teat was 0.77 for B-scan, 0.90 for 3D CCDS, 0.84 for 3D Power Doppler, 0.91 for B-flow and 0.93 for contrast enhanced 3D B-flow. When circular calcifications were present, contrast enhanced flow detection of 3D B-flow proved to be useful. Visualisation of intrastenotic variances of severe and profound stenosis (70-99%) without blooming and reverberation artefacts was possible only with 3D B-flow. This facilitates the detection of the morphology of plaques ulcers as an embolic source. CONCLUSION: In correlation with surgery and CTA/MRA, a valid evaluation of the extent and morphology of ICA stenosis using 3D B-flow, with and without contrast medium, is feasible.

[Retrospective investigation of seasonal factors influencing intraocular pressure in glaucoma patients]. / Retrospektive Untersuchung jahreszeitlich bedingter Einflussfaktoren auf den Augeninnendruck therapierter Glaukompatienten.

BACKGROUND: Some studies in the literature claim a significant seasonal variation of intraocular pressure (IOP) due to the influence of various factors. The aim of our study was to examine such influences on IOP in the Caucasian population. PATIENTS AND METHODS: For a period of 12 years, the data of 172 glaucoma patients from the outpatient glaucoma clinic of the Technical University of Munich were retrospectively evaluated. Most patients had been medically treated to lower their IOP. RESULTS: Slight seasonal variations were found, with the months of low sunlight correlating with higher measurements than the months of high sunlight. The statistical significance of seasonal variation shown in other studies could not be confirmed in this study. CONCLUSION: The seasonal variation of IOP was not statistically significant in our population. A reason for this finding could be that the patients were using glaucoma medication.

Hypergonadotropic hypogonadism in a patient with inv ins (2;4).

We report on a 30-year-old man with azoospermia, primary hypogonadism and minor dysmorphic features who carried a balanced insertional chromosome translocation inv ins (2p24;4q28.3q31.22)de novo. Molecular cytogenetic analyses of the chromosome breakpoints revealed the localization of the breakpoint in 4q28.3 between BACs RP11-143E9 and RP11-285A15, an interval that harbours the PCDH10 gene. In 4q31.22, a breakpoint-spanning clone (RP11-6L6) was identified which contains the genes LSM6 and SLC10A7. On chromosome 2, BACs RP11-531P14 and RP11-360O18 flank the breakpoint in 2p24, a region void of known genes. In conclusion, the chromosome aberration of this patient suggests a gene locus for primary hypogonadism in 2p24, 4q28.3 or 4q31.2, and three possible candidate genes (LSM6, SLC10A7 and PCDH10) were identified by breakpoint analyses.

Multiparameter scoring system for the prognosis of differentiated thyroid cancer.

UNLABELLED: The AIM of the study was to develop a scoring system consisting of multiple parameters that are significant for prognosis of thyroid cancer. The score was designed to permit a risk stratification with all available information at any time of presentation. PATIENTS, METHODS: A score using 25 parameters was used for 171 patients with differentiated thyroid cancer, who were included in follow up over a mean of 9 (+/- 5) years. The significance of each parameter as well as of a summation outcome score was determined. The result of this scoring system was compared to other scores reported in the literature applied to the same patients' group. Thirty-two out of the 171 patients presented with recurrence during follow up. RESULTS: The summation score was highly significant for prognosis of differentiated thyroid cancer. Out of 25 parameters, 18 showed a significant association with outcome also as individual parameters. In comparison to the scores commonly used, this new system showed the highest significance (p < 0.0001, chi square 90, df 1) to estimate recurrence free survival. At a cutoff of -5.95 the sensitivity and specificity for the distinction between high and low risk patients were 87.5 and 77.0%, respectively. CONCLUSION: With our multiparameter scoring system a reliable prognosis with respect to recurrence free survival is possible in patients suffering from differentiated thyroid cancer. A summation score of all parameters gives the best results. Scoring is also possible, if several important parameters are missing.

FDG uptake after intraarterial chemotherapy in head and neck cancer.

AIM: The intraarterial chemotherapy (i.a.CHT) using high dose cisplatin combined with systemic neutralization in patients with head and neck cancer (HNSCC) is used to reduce the tumor volume preoperatively. Aim of the study is the evaluation of the influence of i.a.CHT on the metabolism of fluor-18-deoxyglucose (FDG) in the primary and lymph nodes (LN). The value of FDG positron emission tomography (PET) preoperative and as follow-up method after i.a.CHT is examined. PATIENTS, METHODS: Altogether 16 patients with HNSCC underwent two preoperative FDG PET examinations: the baseline examination one week before and the follow-up three weeks after i.a.CHT. The SUVmax values of the primary and the LN and LN metastases were evaluated and compared with each other and the histopathology. RESULTS: The SUVmax value of the primary decreased after i.a.CHT significantly from a median (25 (th) percentile/75 (th) percentile) of 6.4 (4.1/7.8) to 3.6 (2.4/6.7) (p = 0.01). In 11 out of 16 patients cervical LN metastases were detected. The cervical LN metastases showed a decrease of the SUVmax value from 3.6 (2.3/4.8) in the pretreatment examination to 2.3 (1.7/3.6) after i.a.CHT (p = 0.008). Only in one patient with LN metastases the SUVmax of the nodes increased. The histopathologically measured size of the LN metastases ranged from 2 to 30 mm. Non malignant LN did not reveal a significant SUVmax decrease after i.a.CHT (p = 0.13). CONCLUSIONS: As expected, primaries of HNSCC showed a significant reduction of SUV after i.a.CHT. Compared to the primary the SUVmax decrease in LN metastases was less, but also significant. Since cytotoxic levels of cisplatin do not occur systemic, postinflammatory reactions of the LN or a lymphatic drainage of the chemotherapeutic drug into the LN could be an explanation. PET for staging of HNSCC must thus be performed prior to i.a.CHT.