Die besonderen konstruktionsmerkmale des japanischen „Tan-to“-(Messers) als Kriterien für dessen Gefährlichkeit

Zusammenfassung Es wird auf die besondere Klingenform japanischer Blankwaffen und auf die Neuentwicklung eines Verwandlungs-Tan-to verwiesen. Bei letzterem läßt sich die Klinge in der Handgriffmitte um 90° drehen und arretieren, eine ideale Fixierung dieses Messers durch Faustschluß am Quergriff. Durch diese Bedingungen ist eine hohe Verletzungsgefährdung mit tödlichem Ausgang gegeben. Diese seit kurzer Zeit im Handel erhältlichen Messer sollten nach § 37 Waff G umgehend als verbotene Gegenstände definiert werden.     

Characterization of IMPY as a potential imaging agent for β-amyloid plaques in double transgenic PSAPP mice

Deposition of -amyloid (A) plaques in the brain is likely linked to the pathogenesis of Alzheimers disease (AD). Developing specific A aggregate-binding ligands as in vivo imaging agents may be useful for diagnosis and monitoring the progression of AD. We have prepared a thioflavin derivative, 6-iodo-2-(4-dimethylamino-)phenyl-imidazo[1,2-a]pyridine, IMPY, which is readily radiolabeled with ¹²⁵I/¹²³I for binding or single-photon emission computerized tomography (SPECT) imaging studies. Characterization of [¹²⁵I]IMPY binding to plaque-like structures was evaluated in double transgenic PSAPP mice. [¹²⁵I]IMPY labeled A plaques in transgenic mouse brain sections, and the labeling was consistent with fluorescent staining and A-specific antibody labeling. Significant amounts of A plaques present in the cortical, hippocampal, and entorhinal regions of the transgenic mouse brain were clearly detected with [¹²⁵I]IMPY via ex vivo autoradiography. In contrast, [¹²⁵I]IMPY showed little labeling in the age-matched control mouse brain. Tissue homogenate binding further corroborated the A plaque-specific distribution in various brain regions of transgenic mouse, and correlated well with the known density of A deposition. Using a tissue dissection technique, [¹²⁵I]IMPY showed a moderate increase in the cortical region of transgenic mice as compared to the age-matched controls. In vitro blocking of [¹²⁵I]IMPY by carrier observed via autoradiography in mouse brain sections was not replicated by an in vivo blocking experiment in living TT mouse brain. The failure was most likely due to a significant carrier effect, which slows down the tracer in vivo metabolism, leading to an increased brain uptake. Taken together, these data indicate that [¹²³I]IMPY is a potentially useful SPECT imaging agent for in vivo labeling of A plaques in the living brain.     

Alterations in an indium-111 Fab′ under conditions of utilization

This study was conducted to investigate alterations that occur in an indium/111 Fab of a monoclonal antibody following its in vivo administration. Patients were infused with 111 In-Fab of the monoclonal antibody ZCE-025. Serum and urine specimens were collected from these patients. Starting materials, serum, urine and controls samples were studied by electrophoresis. Animal distribution studies were performed in normal Balb/c mice and, in some cases, nude mice bearing a carcinoembryonic antigen (CEA)/producing human colon tumour since the antibody targets CEA. The studies indicated that the molecule circulated almost totally intact for at least 4 h and to a considerable extent for 24 h, with some evidence for in vivo fragmentation by 24 h. Evidence was also obtained suggesting the formation of a high molecular weight species in some patients. Shortly after infusion, some of the ¹¹¹In in the urine appeared as the intact Fab, but within hours the majority migrated electro-phoretically as low molecular weight species. We conclude that while the majority of the ¹¹¹In-Fab of this particular antibody remains intact and immunoreactive following its administration, the molecule is structurally changed to some degree shortly after its infusion into humans. Since each monoclonal antibody is unique, the degree and rapidity of degradation of its Fab in vivo could vary markedly from the above and possibly adversely effect its utility as a radiopharmaceutical. Offprint requests to: S.E. Halpern Funded by the Veterans Administration     

Usefulness of brain <Superscript>99m</Superscript>Tc-TRODAT-1 SPET for the evaluation of Parkinson’s disease

Nigral dopaminergic projections to the striatum are targeted in Parkinsons disease (PD). The extent of the degeneration of the dopaminergic system in PD can be visualised by dopamine transporter imaging using single-photon emission tomography (SPET). In this study in 188 patients with PD, we analysed the image patterns and compared them with the clinical features in order to verify the usefulness of technetium-99m TRODAT-1 brain SPET in the evaluation of patients with PD. Two independent readers visually assessed SPET slices from three brain axes according to a fine visual scale; results were also grouped according to a rough visual scale. Results of both visual and semi-quantitative analyses were compared among patients with different stages of PD and healthy controls. There was good agreement between the readers in the interpretation of the image patterns [kappa statistic ()=0.85 for the presence of PD; =0.88 for the rough scale and 0.81 for the fine scale]. Good concordance was obtained when visual interpretation was used to evaluate the presence of PD (sensitivity =98%, specificity =86%, =0.85). Semi-quantitative analyses revealed significant negative correlations between both striatal and putaminal uptake and disease severity as assessed using the Hoehn and Yahr scale (=–0.89 and –0.93 respectively). An apparent decrease in striatal uptake in early PD, hardly discernible from the uptake level in advanced PD, was commonly found in visual analyses. The results suggest that both visual and semi-quantitative analyses of ^99mTc-TRODAT-1 SPET images reflect neurodegeneration in PD, and that ^99mTc-TRODAT-1 SPET represents an adequate means for evaluation of the status of patients with PD.     

γ-Glutamyltransferase test as a new tool for identification of seminal stains

Summary A simple qualitative method for identification of seminal stains based on a high activity of -glutamyltransferase (-GTP) in human semen is described. It employs the release of -naphthylamine from N--glutamyl--naphthylamide by the -GTP action; -naphthylamine couples with Fast Garnet GBC salt to produce a strong brownish-red color. The data on its simplicity, specificity, and stability show that the present method is suitable for medicolegal examination of seminal stains as a preliminary test.     

The dynamics of inflammatory cytokines in the healing process of mouse skin wound: A preliminary study for possible wound age determination

The dynamics of inflammatory cytokines such as interleukin-1 (IL-l, interleukin-1 (IL-1), interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF) during the healing process of mouse skin wounds were examined using the enzyme-linked immunosorbent assay and immunostaining. The applicability of this examination for wound age estimation is discussed from the perspective of forensic pathology. After wound induction, mice were sacrificed at intervals ranging from 0 to 240 h. The levels of TNF and IL-1 began to elevate rapidly after wounding and reached a peak at 3 h. The IL-l level reached a peak at 6 h, and IL-6 peaked at 12 h. An infiltration of numerous leukocytes, indicatingacute inflammation, was observed at 3 and 6 h, and the main source of the cytokines was immunohistochemically identified as neutrophils. These results indicate that TNF and IL-1 play an important role in the commencement of inflammation. Rebound of cytokine levels, i.e. a re-increase, was observed at 72 h after wounding. Histological examination of the 72-h-old wound showed migration of fibroblasts and the formation of new granulation tissues, indicating the proliferative stage of the wound healing process. These experimental findings indicate that these cytokines have a close relationship to wound remodeling as well as to inflammation. From the viewpoint of forensic pathology, it is considered that inflammatory cytokines may become one of the markers for wound age estimation, but further studies are needed, especially those involving the investigation using human wound specimens with known time intervals after injury.This study was presented at the 79th Congress of the Medico-Legal Society of Japan (Yamagata, May 1995), the 16th Annual Meeting of the Japanese Society of Inflammation (Tokyo, July 1995) and the 74th Annual Meeting of the German Society of Legal Medicine (Aachen, September 1995).     

PET imaging of brain with the β-amyloid probe, [11C]6-OH-BTA-1, in a transgenic mouse model of Alzheimer’s disease

Purpose The purpose of this study was to evaluate the capacity of [¹¹C]6-OH-BTA-1 and positron emission tomography (PET) to quantify -amyloid (A) plaques in the Tg2576 mouse model of Alzheimers disease (AD).Methods PET imaging was performed with the NIH ATLAS small animal scanner in six elderly transgenic mice (Tg2576; age 22.0±1.8 months; 23.6±2.6 g) overexpressing a mutated form of human -amyloid precursor protein (APP) known to result in the production of A plaques, and in six elderly wild-type litter mates (age 21.8±1.6 months; 29.5±4.7 g). Dynamic PET scans were performed for 30 min in each mouse under 1% isoflurane inhalation anesthesia after a bolus injection of 13–46 MBq of [¹¹C]6-OH-BTA-1. PET data were reconstructed with 3D OSEM. On the coronal PET image, irregular regions of interest (ROIs) were placed on frontal cortex (FR), parietal cortex (PA), striatum (ST), thalamus (TH), pons (PO), and cerebellum (CE), guided by a mouse stereotaxic atlas. Time–activity curves (TACs) (expressed as percent injected dose per gram normalized to body weight: % ID-kg/g) were obtained for FR, PA, ST, TH, PO, and CE. ROI-to-CE radioactivity ratios were also calculated. Following PET scans, sections of mouse brain prepared from anesthetized and fixative-perfused mice were stained with thioflavin-S.Results TACs for [¹¹C]6-OH-BTA-1 in all ROIs peaked early (at 30–55 s), with radioactivity washing out quickly thereafter in both transgenic and wild-type mice. Peak uptake in all regions was significantly lower in transgenic mice than in wild-type mice. During the later part of the washout phase (12–30 min), the mean FR/CE and PA/CE ratios were higher in transgenic than in wild-type mice (1.06±0.04 vs 0.98±0.07, p=0.04; 1.06±0.09 vs 0.93±0.08 p=0.02) while ST/CE, TH/CE, and PO/CE ratios were not. Ex vivo staining revealed widespread A plaques in cortex, but not in cerebellum of transgenic mice or in any brain regions of wild-type mice.Conclusion Marked reductions in brain uptake of this radioligand in transgenic mice may be due to reduced cerebral blood flow relative to that in wild-type mice. Specific [¹¹C]6-OH-BTA-1 binding to A plaques, if any, is probably very low, as reflected in the small FR/CE and PA/CE ratio differences. FR/CE and PA/CE ratios are considerably higher in AD patients while A plaque densities in 22-month-old transgenic mice may be expected to show essentially the same density as is observed in the AD brain. This implies that the absence of tracer retention in 22-month-old transgenic mice may be due to the smaller number of A plaque binding sites and/or to lower affinity of the binding sites for [¹¹C]6-OH-BTA-1 as compared with AD patients. [¹¹C]6-OH-BTA-1 shows excellent brain uptake in mice.This work was presented at the 51st Annual Meeting of the Society of Nuclear Medicine in Philadelphia, PA, June 19–23, 2004.     

Biodistribution of iodine-125 tyramine transforming growth factor α antisense oligonucleotide in athymic mice with a human mammary tumour xenograft following intratumoral injection

The Watson-Crick base pairing rule provides the underlying principle for the antisense (AS) approach to inhibiting gene expression. Transforming growth factor (TGF) was the first growth factor to be associated with tumorigenesis, thus making the TGF (mRNA) a potential target for AS therapy and offering the potential for monitoring of the progression of malignancy by non-invasive imaging with radiolabelled AS phosphodiester. Probe labelling and biodistribution were studied in the present report. A 23-mer oligonucleotide sequence was synthesized and grafted in 5 with a tyramine group which was further radioiodinated. The radiolabelled AS was injected intratumorally in mammary tumour-bearing BALB/c mice (3 weeks after inoculation of 7·10⁶ NS2T2A mammary cells). Biodistribution was monitored by sequential scintigraphy and organ radioactivity after autopsy. The 5 tyramine group allowed specific and stable radiolabelling of the AS with¹²⁵I. The¹²⁵I AS oligonucleotide was rapidly cleared from the tumour by intestine and kidneys. Four hours after intratumoral injection, 6.5%±1.5% of the dose was retained in the tumour as non-degraded¹²⁵I AS. It is concluded that 5 tyraminylated AS provides information on the biodistribution of AS oligonucleotide following intratumoral injection. These data will contribute to the pharmacology of AS oligonucleotides which can be used for therapy.     

Stability of α-[11C]methyl-l-tryptophan brain trapping in healthy male volunteers

Purpose The purpose of this study was to assess the reproducibility in healthy volunteers of -[¹¹C]methyl-l-tryptophan ([¹¹C]MT) brain trapping imaging with positron emission tomography (PET), using volumes of interest (VOIs) and voxel-based image analysis.Methods Six right-handed healthy male volunteers (34.3±10.9 years) with a negative family history for psychiatric disorders were scanned twice in the resting condition, 22±17 days apart. An unbiased semiautomatic segmentation of the brain was used to define VOIs. The trapping constant K* (ml g^–1 min^–1) for [¹¹C]MT was calculated for the whole brain and seven brain regions using the graphical method for irreversible tracers. In addition, parametric maps of K* were obtained from dynamic scans using the same method. Comparison of test and retest K* functional images was performed using SPM99. Students paired t statistic was applied for comparisons of [¹¹C]MT brain trapping in a priori selected VOIs.Results [¹¹C]MT brain trapping in VOIs showed a mean variability 2.6±1.8% (0.3–5%) for absolute and 1.5±2.1% (1.4–4.1%) for normalized K*. Intraclass correlations between test and retest conditions were 0.61±0.34 for absolute K* values and 0.73±0.20 for K* values normalized by global mean. SPM99 analysis using a height threshold of p=0.05 (two tailed) and an extent threshold of 100 voxels showed no significant differences between scans.Conclusion Rest measurements in healthy male volunteers of the trapping constant for [¹¹C]MT, using PET, appeared to be stable during an average interval of 3 weeks.     

Comparison of iodine-123 labelled 2β-carbomethoxy-3β-(4-iodophenyl)tropane and 2β-carbomethoxy-3β-(4-iodophenyl)-N-(3-fluoropropyl)nortropane for imaging of the dopamine transporter in the living human brain

Several cocaine congeners are of potential for imaging the dopamine transporter (DAT). Previous studies have shown that iodine-123 labelled 2-carbomethoxy-3-(4-iodophenyl)tropane ([¹²³I]-CIT) is a promising radiotracer for imaging the serotonin (5-HT) and dopamine (DA) transporters in the living human brain with single-photon emission tomography (SPET). [¹²³I]-CIT was found to be not very practical for 1-day DAT imaging protocols since peak DAT uptake occurs later than 8 h. Here we report a pilot comparison of [¹²³I]-CIT and 2-carbomethoxy-3-(4-iodophenyl)-N-(3-fluoropropyl)nortropane ([¹²³I]-CIT FP), using SPET imaging in four healthy male subjects. Peak uptake of [¹²³I]-CIT-FP into the basal ganglia occurred earlier (3–4 h after injection of tracer) than that of [¹²³I]-CIT (>8 h). However, the specific DAT binding of [¹²³I]-CIT-FP in the basal ganglia was somewhat less (0.813±0.047) than that of [¹²³I]-CIT (0.922±0.004). Imaging quality is excellent with both tracers and they are potentially of value for brain imaging in various neuropsychiatric disorders.     

Ossification and pseudoepiphysis formation in the “nonepiphyseal” end of bones of the hands and feet

Metacarpals, metatarsals, and phalanges were studied to assess the developmental morphology of secondary ossification in the nonepiphyseal ends of these bones as well as the formation of the pseudoepiphysis as an epiphyseal ossification variant. Both direct ossification extension from the metaphysis into the epiphysis and pseudoepiphysis formation preceded, and continued to be more mature than, formation and expansion of the classic epiphyseal (secondary) ossification center at the opposite end of each specific bone. Direct metaphyseal to epiphyseal ossification usually started centrally and expanded hemispherically, replacing both physeal and epiphyseal cartilage simultaneously. In contrast, when remnants of physis were retained, while juxtaposed epiphyseal cartilage was replaced, a pseudoepiphysis formed. There were three basic patterns of pseudoepiphysis formation. First, a central osseous bridge extended from the metaphysis across the physis into the epiphysis and subsequently expanded to create a mushroom-like osseous structure. In the second pattern a peripheral osseous bridge formed, creating either an osseous ring or an eccentric bridge between the metaphysis and the epiphysis. In the third pattern, multiple bridging occurred. In each situation the associated remnant physis lacked typical cell columns and was incapable of significantly contributing to the postnatal longitudinal growth of the involved bone. Pseudoepiphyses were well formed by 4–5 years and coalesced with the rest of the bone months of years before skeletal maturation was attained at the opposite epiphyseal end, which ossified in the typical pattern (i.e., formation of a secondary center de novo completely within the cartilaginous epiphysis). This process may also affect the development and appearance of ossification within the longitudinal epiphyseal bracket (delta phalanx).     

Virtopsy

Zusammenfassung Computed-tomography-Verfahren sind während der letzen 10 Jahre weiterentwickelt worden und haben verschiedene Anwendungen im rechtsmedizinischen Fachgebiet gefunden. Die neueste Entwicklung besteht in der multislice computed tomography, kombiniert mit photogrammetry-based surface optical scanning und Image-rendering-Techniken. Diese Kombination kann für die 3-dimensionale Darstellung von Verletzungsmustern zum Vergleich mit infrage kommenden Tatwaffen sowie zum Screening nach pathologischen Befunden in lebenden oder verstorbenen Personen eingesetzt werden. Es handelt sich um ein minimal-invasives Verfahren, mit dem forensisch relevante Bilder erfasst werden können, die auch im Gerichtssaal vorgeführt werden können. Die rasche Weiterentwicklung der Imaging-Technnik könnte in der Zukunft eine Alternative zur konventionellen Obduktionen darstellen.     

In vitro and in vivo characterisation of nor-β-CIT: a potential radioligand for visualisation of the serotonin transporter in the brain

Radiolabelled 2-Cabomethoxy-3-(4-iodophenyl)tropane (-CIT) has been used in clinical studies for the imaging of dopamine and serotonin transporters with single-photon emission tomography (SPET). 2-Carbomethoxy-3-(4-iodophenyl)nortropane (nor--CIT) is a des-methyl analogue of -CIT, which in vitro has tenfold higher affinity (IC₅₀=0.36 nM) to the serotonin transporter than -CIT (IC₅₀=4.2 nM). Nor--CIT may thus be a useful radioligand for imaging of the serotonin transporter. In the present study iodine-125 and carbon-11 labelled nor--CIT were prepared for in vitro autoradiographic studies on post-mortem human brain cryosections and for in vivo positron emission tomography (PET) studies in Cynomolgus monkeys. Whole hemisphere autoradiography with [¹²⁵I]nor--CIT demonstrated high binding in the striatum, the thalamus and cortical regions of the human brain. Addition of a high concentration (1 M) of citalopram inhibited binding in the thalamus and the neocortex, but not in the striatum. In PET studies with [¹¹C]nor--CIT there was rapid uptake of radioactivity in the monkey brain (6% of injected dose at 15 min) and high accumulation of radioactivity in the striatum, thalamus and neocortex. Thalamus to cerebellum and cortex to cerebellum ratios were 2.5 and 1.8 at 60 min, respectively. The ratios obtained with [¹¹C]nor--CIT were 20%–40% higher than those previously obtained with [¹¹C]-CIT. Radioactivity in the thalamus and the neocortex but not in the striatum was displaceable with citalopram (5 mg/kg). In conclusion, nor--CIT binds to the serotonin transporter in the primate brain in vitro and in vivo and has potential for PET and SPET imaging of the serotonin transporter in human brain.     

Thyroid abnormality secondary to tortous carotid artery

A 59-year-old man was referred to the nuclear medicine service for a thyroid scan, as his neck was thick and the thyroid was not palpable. In the past the patient had undergone head and neck irradiation for acne. A¹²³I-thyroid scan was interpreted as a cold nodule in the lower pole of the right lobe, but thyroid ultrasound showed no thyroid abnormality. Repeat ultrasound examination eventually showed a tortuous carotid artery behind the lower pole of the right lobe of the thyroid that corresponded to the cold defect.     

Experience with the PCR-based HLA-DQα DNA typing system in routine forensic casework

Summary The results of HLA-DQ typing from 42 routine forensic cases using the polymerase chain reaction (PCR) were analyzed regarding the reliability, discrimination efficiency and informative value of this system in a given case. The cases included stain typing from a variety of different substrates, i.e. blood and semen stains, mixed body fluids, single hairs, cigarette butts, material from fingernail scratches, as well as identification and paternity cases on postmortem and fixed tissue. A total of 125 individual stain and tissue samples were included. PCR amplification was achieved in 70% of these samples. In cases with mixed body fluids, e.g. sperm and vaginal cells from rape cases, DQ typing was always carried out successfully. However, only approx. 42% of all samples that could be typed were relevant regarding the inclusion or exclusion of a suspect. This was mostly due to the limited number of alleles that can be typed at the HLA-DQ locus or to the fact that the stain or hair samples did not originate from the perpetrator, but from the victim or from other persons not related to the crime.     

Symptomatic vertebral hemangiomas: a report of four cases

Neural compression complicating vertebral hemangioma is associated with: (1) compression fracture, (2) hematoma, (3) epidural extension of tumor, and/or (4) bony expansion or ballooning. Four cases of symptomatic vertebral hemangioma are presented. Discussion includes imaging modalities, preoperative embolization, and surgical approach.     

A new model for separation between brain dopamine and serotonin transporters in <Superscript>123</Superscript>I-β-CIT SPECT measurements: normal values and sex and age dependence

¹²³I--CIT is a radioactive ligand for single-photon emission computed tomography (SPECT) imaging of the pre-synaptic (transporter) re-uptake sites for dopamine (DAT) and serotonin (5HTT), and it is widely used to visualize monoamine turnover. Since ¹²³I--CIT uptake occurs at 5HTT and DAT sites in conjunction with the presence of freely soluble ¹²³I--CIT in brain tissue, adequate separation of these three components is necessary. However, only partial separation is possible with current methods. Two main strategies have previously been used for ¹²³I--CIT component separation, based on the following considerations: (1) the faster uptake rate for 5HTT compared with DAT enables temporal separation by performing 5HTT imaging at 1–2 h and DAT imaging at 20–24 h; (2) blocking the 5HTT re-uptake with citalopram renders ¹²³I--CIT imaging DAT (non-5HTT) specific. In a new analytical model, we combined these two approaches with methods to isolate the passively dissolved ¹²³I--CIT in brain tissue from the monoamine transporter uptake, and to correct the 5HTT and DAT values for concomitant uptake. The new analytical model was used to study brain 5HTT and DAT in 23 normal subjects, with the aim of clarifying the effect of age and sex. A significant correlation between 5HTT and DAT values was found only in the thalamus, indicating successful component separation. Negative correlations between age and DAT were found for basal ganglia, thalami, brain stem and temporal lobes, but not for the frontal, parietal or occipital regions. No correlation with age was found for 5HTT. We found no sex difference for 5HTT or DAT.     

Positron emission tomography imaging of adrenal masses: <Superscript>18</Superscript>F-fluorodeoxyglucose and the 11β-hydroxylase tracer <Superscript>11</Superscript>C-metomidate

Purpose ¹¹C-metomidate (MTO), a marker of 11-hydroxylase, has been suggested as a novel positron emission tomography (PET) tracer for adrenocortical imaging. Up to now, experience with this very new tracer is limited. The aims of this study were (1) to evaluate this novel tracer, (2) to point out possible advantages in comparison with ¹⁸F-fluorodeoxyglucose (FDG) and (3) to investigate in vivo the expression of 11-hydroxylase in patients with primary aldosteronism.Methods Sixteen patients with adrenal masses were investigated using both MTO and FDG PET imaging. All patients except one were operated on. Five patients had non-functioning adrenal masses, while 11 had functioning tumours(Cushings syndrome, n=4; Conns syndrome, n=5; phaeochromocytoma, n=2). Thirteen patients had benign disease, whereas in three cases the adrenal mass was malignant (adrenocortical cancer, n=1; malignant phaeochromocytoma, n=1; adrenal metastasis of renal cancer, n=1).Results MTO imaging clearly distinguished cortical from non-cortical adrenal masses (median standardised uptake values of 18.6 and 1.9, respectively, p<0.01). MTO uptake was slightly lower in patients with Cushings syndrome than in those with Conns syndrome, but the difference did not reach statistical significance. The expression of 11-hydroxylase was not suppressed in the contralateral gland of patients with Conns syndrome, whereas in Cushings syndrome this was clearly the case. The single patient with adrenocortical carcinoma had MTO uptake in the lower range.Conclusion MTO could not definitely distinguish between benign and malignant disease. FDG PET, however, identified clearly all three study patients with malignant adrenal lesions. We conclude: (1) MTO is an excellent imaging tool to distinguish adrenocortical and non-cortical lesions; (2) the in vivo expression of 11-hydroxylase is lower in Cushings syndrome than in Conns syndrome, and there is no suppression of the contralateral gland in primary aldosteronism; (3) for the purpose of discriminating between benign and malignant lesions, FDG is the tracer of choice.     

“Menigeal sign”: a characteristic finding of meningiomas on contrast-enhanced MR images

Summary In meningiomas, a flat, contrast-enhancing, probably dural structure adjacent to the tumor can occasionally be observed on Gadolinium-DTPA enhanced MR images. This so called meningeal sign was evaluated with respect to the differential diagnosis of meningiomas in MR imaging. The study included 29 patients with intracranial meningiomas and 24 patients with non-meningeal brain tumors. In all meningiomas, MR studies included T2-weighted as well as unenhanced and Gadolinium-DTPA-enhanced T1-weighted images. In all nonmeningeal tumors, Gd-DTPA-enhanced MR images were available. All images were evaluated with respect to the presence of the meningeal sign. In meningiomas, a meningeal sign was seen in 15/29 cases on Gadolinium-DTPA-enhanced images. No abnormalities corresponding to the areas of contrast enhancement were found on unenhanced T2- and T1-weighted MR images. In nonmeningeal tumors only 2/24 cases showed a meningeal sign. In conclusion, with a sensitivity of 52% and a specificity of 92%, the demonstration of the meningeal sign improved the differential diagnosis of intracranial meningiomas in contrast-enhanced MR imaging.     

Cerebral angiographic findings in thromboangiitis obliterans

Transient ischemic attacks (TIAs) or ischemic stroke may complicate thromboangiitis obliterans (TAO). However, there has been debate regarding the mechanism of ischemic stroke in TAO. We report the case of a patient with TAO who developed repeated TIAs. An angiogram showed multiple alternative areas of arterial occlusions in the distal segments of both middle cerebral arteries. Extensive collateral vessels around the occluded segment were also observed, which resembled the tree root or corkscrew vessels described in the peripheral arteries in TAO. Our patient illustrates that cerebral manifestations of TAO may occur with vascular changes that are identical with those encountered in the limb arteries in TAO.