Search

The central nervous system inflammatory disease can be due to any kind of infective agent (bacterial viral, fungal and parasitic), but entails also multiple sclerosis, a primary demyelinating disease in which the causal agent is unknown. MR imaging is, in most often, the procedure of choice, due to her multiplanar and multiparametric imaging, and to her better contrast resolution. The post-contrast imaging with double dose of gadolinium and late sequences enable visualisation of smallest pathologic foci or slightest blood-brain barrier alterations, with a sensibility very higher than post-contrast CT scan. In addition, RM provide to many functional informations, by means of diffusion, perfusion and spectroscopy studies, Bold technique for cortical activation studies and Fiber Tracking technique, in order to demonstrate pathologic modification earlier than they are evident on morphologic imaging. Functional imaging is also employed to monitor response to treatment and damage reversibility.

A large body of evidence indicates that the hormone erythropoietin (EPO) exerts beneficial effects in the central nervous system (CNS). To date, EPO's effect has been assessed in several experimental models of brain and spinal cord injury. This study was conducted to validate whether treatment with recombinant human EPO (rHuEPO) would limit the extent of injury following experimental TBI. Experimental TBI was induced in rats by a cryogenic injury model. rHuEPO or placebo was injected intraperitoneally immediately after the injury and then every 8h until 2 or 14days. Forty-eight hours after injury brain water content, an indicator of brain edema, was measured with the wet-dry method and blood-brain barrier (BBB) breakdown was evaluated by assay of Evans blue extravasation. Furthermore, extent of cerebral damage was assessed. Administration of rHuEPO markedly improved recovery from motor dysfunction compared with placebo group (P < 0.05). Brain edema was significantly reduced in the cortex of the EPO-treated group relative to that in the placebo-treated group (80.6 ± 0.3% versus 91.8% ± 0.8% respectively, P < 0.05). BBB breakdown was significantly lower in EPO-treated group than in the placebo-treated group (66.2 ± 18.7μg/g versus 181.3 ± 21μg/g, respectively, P < 0.05). EPO treatment reduced injury volume significantly compared with placebo group (17.4 ± 5.4mm3 versus 37.1 ± 5.3mm3, P < 0.05). EPO, administered in its recombinant form, affords significant neuroprotection in experimental TBI model and may hold promise for future clinical applications. © 2007 Elsevier B.V. All rights reserved.

Glioblastoma multiforme (GBM) are the most malignant and vascularized brain tumors. The aberrant vascular phenotype of GBM could be exploited for diagnosis or therapeutic targeting. This study identified new molecular markers of GBM vessels, using a combination of laser capture microdissection (LCM) microscopy, RNA amplification, and microarray analyses to compare vessels from nonmalignant human brain and GBM tumors. Forty-two genes were differentially expressed in GBM vessels compared to nonmalignant brain vessels. Validation of differentially expressed genes was performed by literature mining, Q-PCR, and immunohistochemistry. Among the differentially expressed genes, only 64% were previously associated with vessels, angiogenesis, gliomas, and/or cancer. The upregulation of genes encoding secreted extracellular proteins IGFBP7 and SPARC was confirmed by Q-PCR in LCM-captured vessels. Whereas SPARC and IGFBP7 protein were absent in nonmalignant brain vessels, a distinct immunoreactivity patterns were observed in GBM sections whereby SPARC was strongly expressed in perivascular cells adjacent to GBM vessels while GBM endothelial cells were immunostained for IGFBP7. IGFBP7 immunoreactivity was also detected on the abluminal side of GBM vessels deposited between strands of vascular basal lamina. The study discerns unique molecular characteristics of GBM vessels compared with nonmalignant brain vessels that could potentially be used for diagnostic or therapeutic purposes

Although laser pulses activate concomitantly Adelta and C fibres, the corresponding brain evoked responses remain strictly limited to the Adelta component, without any potential consistent with C-fibre activation. To investigate whether this phenomenon depends on the order of arrival to the cortex ("first come first served" hypothesis) or is simply explained by A-to-C inhibition and/or lower energy associated with the desynchronised C-fibre input, we devised an experiment where the physiological order of arrival to the cortex was artificially inverted. Following a conditioning C-pulse, the cortical response to a second laser stimulus was significantly attenuated, whether it was Adelta or C. Thus, a C-volley was able to depress the response to a subsequent Adelta stimulus, in support of the "first come first served" hypothesis. However, the conditioning C-fibre stimulus attenuated significantly more a subsequent C-volley than a subsequent Adelta-volley, indicating that the suppression effect does not depend solely on the order of arrival to the cortex, but also on the ratio of energy per unit time conveyed by the successive inputs. This supports the notion that cortical evoked potentials to laser pulses (and probably to other sensory stimuli) reflect networks detecting rapid energy changes relative to a preceding baseline. The output of such networks should depend both on the time elapsed between successive inputs and on the relative energy per unit time conveyed by successive volleys. Such dedicated networks aimed at detecting energy changes may be related to orienting reactions, and can be dissociated from subjective perception.

WOS: 000249788900020 PubMed: 17948092 The occurrence rate of transient cortical blindness after contrast media exposure has been reported to be as high as 1% to 4% after cerebral or vertebral angiography, but such blindness has been described in only a few cases of coronary angiography with modem, non-ionic, low-osmolality radio-contrast agents. In this study we present a case of abrupt cortical blindness after exposure to contrast media during diagnostic coronary angiography; to our knowledge, this is the 1st report in the medical literature that describes transient cortical blindness after iobitridol use.

Corticotropin-releasing hormone (CRH) is a key mediator of endocrine, autonomic, behavioral, and immune responses to stress. The ability of CRH to induce hormonal stress responses has been used to investigate the functionality of the hypothalamus-pituitary-adrenal axis, and consequently the activity of hypothalamic CRH neuronal systems. Indeed, CRH administration to humans causes prompt release of ACTH, followed by secretion of cortisol, aldosterone and other adrenal steroids. CRH hypersecretion/hyperactivity has been associated to major depression, anxiety-related disorders, anorexia nervosa, Alzheimer's and Parkinson's diseases and progressive supranuclear palsy. During pregnancy the human placenta and its accessory membranes are the major sites of CRH synthesis and secretion. Placental CRH secretion is autonomous, but increasing evidence indicates that maternal or fetal conditions may influence such secretion. Therefore, the emerging concept is that in the event of acute or chronic metabolic, physical or infectious stress, the placenta takes part in a stress syndrome by releasing CRH, which may contribute to restore local blood flow and to influence the timing of delivery. The CRH released by the placenta is measurable in maternal plasma and other biological fluids and may be used to diagnose subclinical processes anteceding pregnancy complications such as pre-eclampsia and preterm delivery.

Background Diagnostic imaging in women with suspected breast cancer should accurately detect and diagnose malignant tumors and facilitate the correct choice of therapy. Contrast-enhanced magnetic resonance mammography (CE-MRM) is potentially the imaging modality of choice for accurate patient management decisions. Methods A total of 164 women with suspected breast cancer based on clinical examination, conventional mammography and/or ultrasound each underwent preoperative bilateral CE-MRM using an axial 3D dynamic T1-weighted gradient-echo sequence and gadobenate dimeglumine as contrast agent. Images were evaluated by two readers in consensus. Histological evaluation of detected lesions was performed on samples from core biopsy or surgery. Determinations were made of the sensitivity, accuracy and positive predictive value of CE-MRM compared to mammography/ultrasound for the detection of malignant lesions and of the impact of CE-MRM for surgical decision-making. Findings Conventional mammography/ultrasound detected 175 lesions in the 164 evaluated patients. CE-MRM revealed 51 additional lesions in 34/164 patients; multifocal and multicentric cancer was detected in 7 and 4 additional patients, respectively, contralateral foci in 21 additional patients and pectoral muscle infiltration in 2 additional patients. CE-MRM also confirmed the absence or benignity of 3 and 1 lesions suspected of malignancy on mammography/ ultrasound. The sensitivity and accuracy for malignant lesion detection and identification was 100% and 93.4%, respectively, for CE-MRM compared to 77.3% and 72.1% for mammography/ultrasound, respectively. Patient management was altered for 32/164 (19.5%) patients as a result of CE-MRM. Interpretation CE-MRM positively impacts patient management decisions and should be performed in all women with suspected breast cancer based on clinical examination, mammography and/or ultrasound.

Context A characteristic feature of borderline personality disorder (BPD) is self-injurious behavior in conjunction with stress-induced reduction of pain perception. Reduced pain sensitivity has been experimentally confirmed in patients with BPD, but the neural correlates of antinociceptive mechanisms in BPD are unknown. We predicted that heat stimuli in patients with BPD would activate brain areas concerned with cognitive and emotional evaluation of pain. Objective To assess the psychophysical properties and neural correlates of altered pain processing in patients with BPD. Design Case-control study. Setting A university hospital. Participants Twelve women with BPD and self-injurious behavior and 12 age-matched control subjects. Interventions Psychophysical assessment and blood oxygen level–dependent functional magnetic resonance imaging during heat stimulation with fixed-temperature heat stimuli and individual-temperature stimuli adjusted for equal subjective pain in all the participants. Main Outcome Measure Blood oxygen level–dependent functional magnetic resonance imaging signal changes during heat pain stimulation. Results Patients with BPD had higher pain thresholds and smaller overall volumes of activity than controls in response to identical heat stimuli. When the stimulus temperature was individually adjusted for equal subjective pain level, overall volumes of activity were similar, although regional patterns differed significantly. Patient response was greater in the dorsolateral prefrontal cortex and smaller in the posterior parietal cortex. Pain also produced neural deactivation in the perigenual anterior cingulate gyrus and the amygdala in patients with BPD. Conclusion The interaction between increased pain-induced response in the dorsolateral prefrontal cortex and deactivation in the anterior cingulate and the amygdala is associated with an antinociceptive mechanism in patients with BPD.

We investigated myocardial perfusion in acute patients with slow coronary flow (SCF) at angiography. Whether impaired myocardial perfusion occurs in acute patients with SCF is unknown.We enrolled 28 consecutive patients with SCF in the epicardial coronary arteries with no evidence of significant stenosis. SCF affected a single coronary artery in 14 patients (group A) and all three coronary vessels in 14 others (group B). Coronary angiography was repeated after dipyridamole infusion and single photon emission computed tomography was performed using dipyridamole as the stress agent. The Thrombolysis in Myocardial Infarction frame count was measured in SCF vessels at baseline and after dipyridamole infusion.Mean Thrombolysis in Myocardial Infarction frame count significantly decreased after dipyridamole in both groups. At baseline, mean values of the single photon emission computed tomography score were 31.5 +/- 1.6 and 25.1 +/- 2.1 in groups A and B, respectively. After dipyridamole, they increased from 31.5 +/- 1.6 to 37.8 +/- 1.4 (P0.001) in group A, whereas a further decrease to 15.0 +/- 1.2 (P0.005) was observed in group B.An opposite behavior of myocardial perfusion was observed after dipyridamole infusion: a normal response in patients with SCF affecting one single coronary artery versus an ischemic-like response in those with CSF affecting all three coronary arteries.

Sepsis ir jo sukeltos komplikacijos yra pagrindinė mirties priežastis intensyviosios terapijos skyriuose gydomų ligonių. Nepaisant gydymo, mirtingumas nuo sepsio siekia 28–50 proc., o 60–90 proc. ligonių miršta nuo sepsio sukeltų komplikacijų, todėl labai svarbu atpažinti ir laiku diagnozuoti šią patologiją. Sepsio diagnostika yra sudėtinga, nes būdingi klinikiniai požymiai galimi sergantiems neinfekcinėmis ligomis pasireiškus sisteminio uždegiminio atsako sindromui. Klinikinėje praktikoje naudojami uždegiminio atsako parametrai: kūno temperatūra, leukocitų skaičius, eritrocitų nusėdimo greitis ir C reaktyvusis baltymas nėra nei jautrūs, nei specifiniai ir, remiantis jais, negalima atskirti sisteminio uždegiminio atsako sindromo nuo sepsio. Prokalcitoninas yra naujas bakterijų, grybelių ir parazitų sukeltų infekcinių ligų žymuo. Sveikiems žmonėms beveik visas skydliaukėje pasigaminęs prokalcitoninas suskaidomas ir į kraujotaką nepatenka, o plazmoje jo pusinės eliminacijos laikas yra tik kelios minutės, todėl sveikų žmonių kraujyje prokalcitonino koncentracija yra labai maža (

Background. The involvement of reactive oxygen species in periodontal diseases is unclear. The aim of the present study was to explore the oxidative function of neutrophilic leukocytes of the peripheral venous blood in patients with severe periodontitis and type 1 diabetes mellitus and in the control subjects with healthy periodontal tissues and without systemic diseases. Materials and methods. The leukocytes for the present investigation were obtained from peripheral venous blood of 38 patients with severe periodontitis and type 1 diabetes mellitus and 27 control subjects. The maximal luminol-dependent chemiluminescence and peak time values of neutrophils stimulated with non-opsonized Escherichia coli ATCC 25922 and Staphylococcus aureus 256 were measured. Results. The maximal luminol-dependent chemiluminescence of neutrophils in patients with severe periodontitis, stimulated with non-opsonized Escherichia coli and Staphylococcus aureus, is mainly lower than that in the control group subjects (p

The epithelioid hemangioendothelioma of the liver has been recently characterized as a rare tumor with distinctive pathological features affecting young adults. Our report describes a case of histologically confirmed primary epithelioid hemangioendothelioma of the liver, diagnosed by clinical examination as well as radiological (CT/MR) and scintigraphic imaging (labelled red cells/ phytate-SPECT). This case highlights the usefulness of nuclear medicine techniques during the diagnostic of this rare tumor. Further it stresses the possibility of employing an easy and noninvasive method to adequately follow-up those patients who cannot be considered as disease-free even after orthotopic liver transplantation because of the recurrence of the disease in the transplanted liver.

To establish the additional value of MR Spectroscopy (3D CSI MRS Three-dimensional Chemical Shift Imaging Magnetic Resonance Spectroscopy) to endorectal MR in the diagnosis and grading of prostate cancer.MR and 3D CSI MR spectroscopy were performed in 53 patients with suspicion of prostate cancer on the basis of rectal exploration and/or transrectal ultrasound and/or the PSA levels. All the examinations were performed with a 1.5 T imager using an endorectal coil. We acquired axial and coronal T2-weighted FSE sequences, axial T1-weighted SE sequences and PRESS 3D CSI (Point Resolved Spectroscopy 3D Chemical Shift Imaging) sequences localized on the axial T2 images so as to include the prostatic gland while excluding the periprostatic fat. The MR examinations were evaluated by two radiologists unaware of the clinical data, transrectal ultrasound findings, PSA levels and histological findings. The MR and 3D CSI MRS findings were compared with the biopsy findings in 22 cases and with material obtained from laparoscopic prostatectomy in 31 cases.The histological examination revealed adenocarcinoma in 37 cases, prostatitis in 2 cases and no alterations in the remaining 14 cases. The morphologic MR scan showed a sensitivity of 76%, a specificity of 56%, an accuracy of 70%, a PPV of 80% and a NPV of 50%. By combining MR and 3D CSI MRS we obtained a sensitivity of 95%, a specificity of 81%, an accuracy of 91%, a PPV of 92% and a NPV of 87%. Elevated choline concentrations were found both in tumours with a low Gleason score (18 cases) and in those with a high Gleason score (19 cases); instead we found markedly reduced (n=9) or absent (n=4) citrate only in the tumours with a high Gleason score, while we found normal citrate levels in the 18 tumours with a low Gleason score.The 3D CSI MRS improved the reliability of endorectal MR in the diagnosis and characterisation of prostatic cancer. Moreover, the 3D CSI MRS findings demonstrated a linear correlation with tumour grade.

In this paper, we apply independent component analysis to fetal magnetocardiographic data. In particular, we propose an extension of the "cumulant-based iterative inversion" algorithm to include a two-step "signal subspace" subdivision, which allows the user to control the number of components to be estimated by analyzing the eigenvalues distribution in an interactive way. Our results show that this method is a powerful means not only for the extraction of the cardiac signals from the background noise but also for a sharp separation of the baby's heart from the mother's.

To evaluate the role of contrast-enhanced Magnetic Resonance Mammography (MRM) in the evaluation of the contralateral breast in patients with recently diagnosed breast cancer.Fifty patients with proved unilateral breast cancer, with a negative contralateral breast at physical examination, ultrasound and mammography, were studied with a 1.5 T magnet (Siemens, Vision Plus, Germany). A bilateral breast surface coil was used. Dynamic 3D Flash T1-weighted sequences were acquired in the axial plane before and 0, 2, 4, 6 and 8 minutes after the administration of 0.1 mmol/kg of Gd-BOPTA at a flow rate of 2 ml/s followed by 10 ml of saline. The level of suspicion was reported on a scale from 0 to 5 following the BI-RADS classification, based on lesion morphology and kinetic features. The results were compared with the histological findings after biopsy or surgery.Fourteen out of 50 patients (28%) had contralateral lesions identified on MRM. Biopsy was performed in four of them for suspicious lesions (BI-RADS 4) while 10 patients underwent surgery because of highly suggestive malignant lesions (BI-RADS 5). Histology diagnosed three fibroadenomas, 5 ductal carcinomas in situ, 2 lobular carcinomas in situ, 3 invasive ductal carcinomas and 1 invasive lobular carcinoma. Contrast-enhanced MRM yielded no false negative and three false positives.Our results demonstrate a very good accuracy of Magnetic Resonance Mammography in the detection of synchronous contralateral cancer in patients with newly diagnosed breast cancer. Therefore, contrast-enhanced MRM could be introduced to screen patients with proven breast cancer before they undergo surgery.

Defining language lateralisation is important to minimise morbidity in patients treated surgically for temporal lobe epilepsy (TLE). Functional magnetic resonance imaging (fMRI) offers a promising, non-invasive, alternative strategy to the Wada test. Here, fMRI has been used to study healthy controls and patients with TLE in order (i) to define language-related activation patterns and their reproducibility; (ii) to compare lateralisation determined by fMRI with that from the Wada test; and (iii) to explore the usefulness of multiple fMRI language paradigms. 18 healthy controls (12 right-handed and 6 left-handed) and 24 pre-operative TLE patients (19 right-handed: 12 left-TLE, 7 right-TLE; 5 left-handed: 2 right-TLE, 3 left-TLE) were studied using fMRI. Four fMRI language paradigms used: phonetic and semantic fluency, and the naming of living and non-living things. The data for all 4 tasks were acquired during a single scanning session on two occasions. All patients also underwent Wada testing. In patients and controls, phonetic and semantic fluency tasks were robustly activating and strongly lateralising. Quantified language-related lateralisation from fMRI verbal fluency data was highly reproducible and concordant with the lateralisation of the Wada test. Both fluency tasks identified patients with atypical language lateralisation, including 4/12 right-handed patients with left-TLE and 4/5 left-handed TLE patients, regardless of the side of epileptic focus. In comparison, the two confrontational naming tasks were not strongly lateralising and did not reliably agree with Wada lateralisation in either 12 right-handed controls or 19 right-handed patients with TLE. However, there was a difference in the pattern of fMRI activation in right-handed pat ients with left-TLE. Left-TLE patients had a more right lateralised network of activation when naming living things relative to non-living things, suggesting that some patients may be at risk of a category specific naming decline for non-living things after left anterior temporal lobectomy. These results demonstrate that non-invasive fMRI measures of languagerelated lateralisation may provide a practical and reliable alternative to invasive testing for pre-surgical language lateralisation in patients with TLE. The high proportion of TLE patients showing atypical language lateralisation suggests considerable plasticity of language representation in the brains of patients with intractable TLE.

In human blood, breakdown of gastrin-releasing peptide and other bombesin-related peptides occurs in less than 15 min. This quick enzymatic cleavage might impair the diagnostic use of labelled bombesin (BN). 99mTc-labelled bombesin (99mTc BN1) was injected intravenously and dynamic uptake data were acquired for diagnosing 26 cancers of different origin: 15 breast, 3 prostate, 5 colo-rectal, 1 pancreas, 2 small cell lung cancers and 1 gastrinoma. Background subtracted tumour uptake data were plotted against time and fitted with known mathematical functions. Twenty-three out of 26 cancers showed rapid increase of radioactivity followed by a radioactivity plateau, with some oscillations around the average plateau value. The time to 80% of max activity (T80) was the reference parameter to measure and to compare the uptake speeds. The slowest T80 was 7 min in one T1b breast cancer, gastrinoma reached T80 in 5 min and node-positive prostate cancers in 2 min. N+ breast cancers showed T80 at 3.62 +/- 0.75 min, N- breast cancers at 5.5 +/- 0.88 min (p0.02). When all the tumours were considered, N+ tumours showed T80 at 2.68 +/- 1.03 min and N- cancers at 5.5 +/- 0.82 min. In all the cancer types, the uptake of 99mTc BN was faster than 10 min. This result shows the ability of 99mTc BN to image tumours. The faster uptake by N+ versus N- cancers probably depends on the higher blood flow in N+ cancers.

The authors describe the possible application of Tc-99m (V) DMSA scintigraphy in pancreatic neuroendocrine tumors. In consideration of the common embryonic origin of these tumors and other neoplastic diseases (medullary thyroid carcinoma, pheocromocytoma, neuroblastoma) that have been well studied with radionuclide imaging, five cases of pancreatic neuroendocrine tumors (two insulinomas, one vipoma, and two unclassified neuroendocrine tumors) were successfully visualized with Tc-99m (V) DMSA scintigraphy, thus giving an overall "imaging confirmation" of the histologic and/or cytologic results in terms of primary and metastatic localization. The authors point out the importance of their results, obtained in a simple and repeatable manner, and suggest a real comparison in this setting between this approach and octreotide scintigraphy.

Breast, prostate, and lung cancer have been successfully detected with 99mTc bombesin (99mTc-leu13-BN1), the radiopharmaceutical that our group developed from synthesis to diagnostic trials. Overexpression of bombesin receptors (BNRs) in colon cancer is well known: the aim of this study was to assess whether or not colon cancer can be detected with a 99mTc-leu13-BN1 scan. Thirteen (13) patients, 7 of whom with known rectal cancer and 6 scheduled to undergo endoscopic removal of polyps for suspicion of colon cancer, were studied with a 99mTc-leu13-BN1 scan. Dynamic, single photon emission computed tomography, and whole-body scans were performed within 1 hour, before discharge of radioactivity from the liver into the duodenum. Sixteen (16) of 17 colorectal cancer locations were detected with a 99mTc-leu13-BN1 scan with 94.1% sensitivity. Six (6) lesions were benign: 1 Crohn's disease, 1 polyp with mild dysplasia, 4 polyps with simple hyperplasia; 99mTc-leu13-BN1 scans were positive in two nontumoral lesions, Crohn's disease, and mild dysplasia and true negative in 4: specificity was 67%. Of the 7 patients with known rectal cancer, 5, who underwent operations instead of radiation therapy, showed lymph-node invasion on 99mTc-leu13-BN1 scans. Operations confirmed the scintigraphic staging. 99mTc-leu13-BN1 is taken up by colon cancer. Scans are sensitive, although scarcely specific. 99mTc-leu13-BN1 allows for node-invasion detection.

Despite advances in the diagnosis and treatment of infections diseases, sepsis and ensuing multiorgan failure are the major causes of morbidity and mortality in the intensive care units. Such manifestations of systemic inflammation as fever, leukocytosis, tachycardia, etc. may be noninfectious in origin and are neither specific nor sensitive for sepsis. Procalcitonin is a new potential marker for detection of bacterial, fungal and protozoal infections. Procalcitonin, a propeptide of calcitonin, is normally produced in the C-cells of the thyroid gland. Procalcitonin is a polypeptide consisting of 116 amino acids and with a molecular weight of about 13 kDa. During severe systemic infections it is produced by extrathyroidal tissues. Procalcitonin can be put to immediate use in both diagnostic and therapeutic decision-making. This review article discusses biology of procalcitonin, its laboratory determination, usage as an indicator for severe infection and sepsis, and comparison with circulating cytokines in severe infection. It also reviews value of procalcitonin in differentiation of infectious vs non-infectious inflammatory host response, possible elevation of procalcitonin in the absence of infection, its use for differentiation of viral and non-viral infections and as marker for prognosis and evaluation of therapy. Specific indications for determination of procalcitonin are also discussed.

The 17th IRIST (International Research Group on Immunoscitigraphy and Therapy) meeting was held July 27-29, 2004, at the Ghent University Hospital, Ghent, Belgium. Cochairs Christophe Van de Wiele and Alberto Signore brought together basic researchers, clinicians, radiopharmacists, and nuclear medicine specialists to discuss progress in single photon emission computed tomography (SPECT) and positron emission tomography (PET), using radiolabeled antibodies and peptides for imaging biologic properties related to the effectiveness of available treatment options and for treatment of cancer patients. The format of the conference was the presentation of research that focused on the basic and translational biology of cancer and on current state-of-the-art radiopharmacy and related SPECT and PET imaging techniques for the purposes described above. This report summarizes the 17th International IRIST Congress.

Early detection of site and extent of biliary tract disruption can significantly reduce mortality and morbidity in a postoperative biliary leak. We report a case in whom extent and location of post surgical biliary leak was detected with the help of 99mTc BULIDA cholescintigraphy and showed a good correlation with "T" tube cholangiography. Cholescintigraphy was also useful in assessing the follow up of this patient. We conclude that 99mTc BULIDA cholescintigraphy is a non-invasive, safe, simple and sensitive procedure in the detection of the site, extent of the leak and in follow up of the postoperative biliary leak.

Laser pulses excite superficial free nerve endings innervated by small-myelinated (Adelta) and unmyelinated (C) fibres. Whereas laser-evoked scalp potentials (LEPs) are now reliably used to assess function of the Adelta-fibre nociceptive pathways in patients with peripheral or central lesions, the selective activation of C-fibre receptors and recording of the related brain potentials remain difficult. To investigate trigeminal C-fibre function, we directed laser pulses to the facial skin and studied sensory perception and scalp evoked potentials related to Adelta- or C-fibre activation in healthy humans and patients--one having a bilateral facial palsy, two a trigeminal neuropathy, and two a Wallenberg syndrome. We also measured afferent conduction velocity and, with source analysis, studied the brain generators. Whereas laser pulses of low intensity and small irradiated area elicited pinprick sensations and standard Adelta-LEPs, laser pulses of very-low intensity and large irradiated area elicited warmth sensations and scalp potentials with a latency compatible with C-fibre conduction (negative wave 280 ms, positive wave 380 ms); the estimated conduction velocity was 1.2 m/s. The main waves of the scalp potentials originated from the anterior cingulate gyrus; they were preceded by activity in the opercular region and followed by activity in the insular region. The patient with bilateral facial palsy, who had absent trigeminal-facial reflexes, had normal Adelta- and C-related scalp potentials; the patients with trigeminal neuropathy, characterized by loss of myelinated and sparing of unmyelinated fibres, had absent Adelta- but normal C-related potentials; and the patients with Wallenberg syndrome had absent Adelta- and C-related potentials. We conclude that laser pulses with appropriate characteristics evoke brain potentials related to the selective activation of trigeminal nociceptive Adelta or thermal C fibres. The trigeminal territory yields rewarding LEP findings owing to the high density of thermal receptors and, because the short conduction distance, minimizes the problem of signal dispersion along slow-conducting unmyelinated afferents. The opercular-insular region and the cingulate gyrus are involved in the processing of C-fibre trigeminal inputs. The method we describe may prove useful in patients with lesions affecting the trigeminal thermal pain pathways.

Renal transplant recipients should be screened for coronary artery disease. The purpose of this study was to evaluate the usefulness of thallium-201 dipyridamole myocardial perfusion single-photon emission computed tomography (SPECT) to predict major cardiac events in these patients.Eighty-two consecutive patients (61 males) in hemodialysis (HD) treatment, awaiting renal transplantation, underwent dipyridamole Tl-201 SPECT for pretransplant risk stratification. SPECT semiquantitative analysis showed a normal perfusion pattern in 52 patients (group A) and fixed defects in 9 (group B). Reversible perfusion defects were found in 21 (group C). Cardiac death, myocadial infarction, and unstable angina were sought as cardiac events. During a follow-up lasting 28.3 +/- 21.6 months, three patients of group A died for a non-cardiac cause. In group C, six patients (28.6%) had a cadiac event: one had a non-q wave myocardial infarction after renal transplantation; five were admitted with unstable angina. No cardiac events were observed in groups A and B (p = 0.0001). SPECT semiquantitative analysis showed that a summed difference scoreor = 3 significantly increased the risk of cardiac events (odds ratio 4.5, C.I. 2.5-8.1).Cardiac events were only observed in HD patients with Tl-201 SPECT dipyridamole reversible defects (group C). A normal pattern or a fixed defect in Tl-201 dipyridamole SPECT in HD patients identified a good long-term prognosis.

Procedures to qualify turbo-machinery components for a designed lifetime free of high cycle fatigue (HCF) failures have not yet evolved. As part of an initiative to address this issue, in the present study, laser-light probes were used in a Non- Intrusive Measurement System (NSMS) to measure the unsteady deflections created in the blades of a second-stage turbine rotor in an evacuated spin pit. Air-jet and eddy-current excitation (ECE) methods were used to stimulate blade resonance. The NSMS was calibrated directly to gauge measurements of strain, and testing was conducted toward three additional goals; assessing the effectiveness of an advanced internal damping system; attaining higher excitation amplitudes with ECE by silver plating blades, and improving the repeatability of resonance data by adding plastic inserts between the fir-tree blade roots and the disk. It was concluded that the ability of NSMS to record the response of all blades is key to understanding the rotor system behavior and quantifying the statistical variability between blades. http://archive.org/details/resonantbladeres109455982 Lieutenant, United States Navy Approved for public release; distribution is unlimited.

The objective of this study was to evoke sympathetic skin responses (SSRs) in healthy subjects using laser stimulation and to compare these responses with those induced by conventional electrical stimuli. Twenty healthy subjects were investigated. SSRs were obtained using electrical and laser stimuli delivered to the wrist controlateral to the recording site. The sympathetic sudomotor conduction velocity (SSFCV) was measured in 8 subjects by simultaneously recording the SSR from the hand and the axilla. The latency (L) of the laser-induced SSR (ISSR) was significantly longer than that of the electrically-evoked SSR (eSSR) (mean ISSRL= 1.7 +/- 0.145 ms, mean eSSRL= 1.56 +/- 0.14 ms, p0.05). The amplitude (A) of the ISSR was lower than the eSSR amplitude (mean ISSRA = 1.31 +/- 0.26 mV, mean eSSRA = 2.59 +/- 0.49 mV, p0.05). No significant difference between the ISSR and eSSR was observed in either the SSFCV or the variability and reproducibility parameters. Our findings show that SSRs can easily be induced by laser stimuli and that this method shares the technical limitations of conventional eSSRs.

Purpose Hypertensive patients with complete left bundle branch block who experience chest pain present special problems in the radionuclide diagnosis of coronary artery disease (CAD). The aim of this study was to assess the utility of Tc-99m tetrofosmin SPECT for the diagnosis of CAD in 35 hypertensive patients with left bundle branch block hospitalized for chest pain. Materials and Methods Images were analyzed semiquantitatively for the presence of both fixed or reversible perfusion defects (method A) or only reversible defects (method B) in the distribution of the left anterior descending artery (LAD) territory. Perfusion defects observed in the territory of any other coronary artery were always considered. Thirty-five patients without infarction underwent adenosine Tc-99m tetrofosmin SPECT, transthoracic echocardiography, and coronary angiography. Results The mean left ventricular ejection fraction was calculated as 39.9% ± 11.6%, and the prevalence of CAD was 29%. The sensitivity of SPECT was identical for the two methods at 89%. The specificity increased 19% with method A and 54% with method B. The positive predictive value remained unsatisfactorily low with both methods (27% for method A and 40% for method B), and the negative predictive value improved from 83% with method A to 93% with method B. Conclusions Only reversible perfusion defects in the LAD territory should be considered significant for CAD, and these patients should undergo coronary angiography. Reversible or fixed perfusion defects in the left circumflex and right coronary artery territories should be evaluated according to other clinical parameters (global left ventricular ejection fraction, extension of perfusion defects). The highly negative predictive value of adenosine SPECT could help in the exclusion of CAD.

In daily routine diagnosis, there are few parameters available to monitor critically ill patients and to control the course of therapy in severe inflammations. There are also few reliable parameters differentiating acute bacterial infection from other types of inflammation. Most of the presently used indicators of the inflammatory response, like body temperature, white cell count, erythrocyte sedimentation rate or C reactive protein are unspecific parameters with changing reliability. Procalcitonin is a diagnostic parameter of bacterial infections with systemic reaction of the organism. It is an innovative diagnostic parameter with feature different from other presently available indicators of the inflammatory response. The incidence of noninfectious systemic inflammatory response syndrome associated with coronary artery bypass surgery and the potential role of several inflammatory parameters as early markers of pulmonary dysfunction induced by cardiopulmonary bypass were investigated. Procalcitonin seems to be appropriate parameter indicating the early development of severe noninfectious systemic inflammatory response syndrom and for predicting pulmonary dysfunction secondary to cardiopulmonary bypass. Hence, the review of the data of different authors may lead to the conclussion that because of wide spectrum of indications procalcitonin concentration can be used for differential diagnosis of bacterial versus non- bacterial inflammation, as monitoring parameter in critically ill patients, the course of disease, treatment control evaluating the effectiveness of antibacterial treatment, for evaluation of high risk patients to see if there are no postoperative bacterial complications as a prognostc indicator.

Lesions of the mammalian visual cortex cause the retrograde degeneration of the thalamic neurons projecting to the damaged cortex. The proto-oncogene bcl-2 is known to inhibit neuronal apoptosis induced by a variety of noxious stimuli and preserve the functional integrity of the injured cells. Here we have tested whether the overexpression of bcl-2 via adeno-associated virus (AAV) vectors is able to protect the neurons in the lateral geniculate nucleus after visual cortex ablation in adult rats. Recombinant AAV vectors encoding Bcl-2 (AAV-Bcl-2) or green fluorescent protein (AAV-GFP) as a control were stereotaxically injected into the geniculate. Three weeks after vector injection, the ipsilateral visual cortex was removed by aspiration, and cell survival was assessed 2 weeks later. We found that 20\% of the geniculate neurons were transduced by the Bcl-2 vector. These cells were completely protected from death following cortical ablation. Delivery of AAV-GFP transduced an identical number of geniculate neurons but had no effect on cell survival after lesion. The total number of surviving geniculate neurons was found to be significantly higher in animals injected with AAV-Bcl-2 than in rats injected with AAV-GFP or in control lesioned rats. These data indicate that Bcl-2 gene therapy with AAV vectors represents an effective treatment to promote neuronal survival after central nervous system insults.

Purpose To determine whether the increase in intraocular pressure (IOP) for 45 seconds during laser in situ keratomileusis (LASIK) suction can induce a decrease in retinal nerve fiber layer thickness (RNFLT) assessed by a confocal scanning laser polarimeter. Setting Jules Gonin Hospital, University of Lausanne, Lausanne, Switzerland. Methods Eleven normal volunteers were enrolled in the study. The optic disc of each eye was analyzed by the GDx® Nerve Fiber Analyzer (Laser Diagnostic Technologies, Inc.), version 1.0.14. Using the standard circle that appears as a 10-pixel green circle on the GDx display, the system assessed the RNFLT at 1.75 disc diameter from the outer edge of the optic nerve head. To further evaluate the possible retinal nerve fiber layer (RNFL) loss, the 360-degree circumference was divided into 36 segments measuring 10 degrees each and the RNFLT was calculated for each sector. All subjects had a GDx assessment before 100 mm Hg ocular compression of 1 eye for 45 seconds and then 2 minutes and 1 month after compression. Results Before compression, the mean RNFLT was 69.09 μm ± 10.96 (SD); it was 69.27 ± 10.98 μm after 2 minutes and 67.00 ± 10.58 μm after 1 month. No statistically significant difference was found between the before and after measurements. Conclusion A 45-second acute increase in IOP, such as during LASIK suction, did not decrease the RNFLT in normal eyes.

The functional relevance of brain activity during visuospatial tasks was investigated by combining functional magnetic resonance imaging with unilateral repetitive transcranial magnetic stimulation (rTMS). The cognitive tasks involved visuospatial operations on visually presented and mentally imagined material ("mental clock task"). While visuospatial operations were associated with activation of the intraparietal sulcus region bilaterally, only the group which received rTMS to the right parietal lobe showed an impairment of performance during and immediately after rTMS. This functional parietal asymmetry might indicate a capacity of the right parietal lobe to compensate for a temporary suppression of the left. This is compatible with current theories of spatial hemineglect and constitutes a constraint for models of distributed information processing in the parietal lobes.

The present study was aimed at investigating a) the risk of having bulimia in a heterogeneous population of secondary amenorrhea; b) the LH and FSH secretion under basal and stimulated conditions (GnRH challenge) according to the presence of bulimic risk in our study population; c) the clinical and endocrine factors predictive of the bulimic risk in amenorrheic women. Amenorrheic women (n=73; age: 23.1+/-4.8 yrs; BMI:20.2+/-2.2 kg/m2) filled in a self rating scale for bulimia (BITE) and were classified accordingly, as being at low risk (score10), at medium risk (score between 10 and 24), and at high risk (scoreor =25) of having bulimia. In each subject basal mean plasma LH levels were calculated over one hour, sampling every 10 minutes, while in a subgroup of 45 patients the area under the curve (AUC) of plasma LH and FSH levels following a challenge with two doses of GnRH (10+10 microg, every two hours), sampling every 15 minutes, was also evaluated. High risk of bulimia was present in 12.3% of the population whereas 45.2% showed a low risk and 42.5% were at medium risk of developing the disorder. Mann-Whitney U test revealed that basal LH values were differently distributed with significantly lower levels (P0.046) in amenorrheic women at high risk of bulimia in comparison with amenorrheic women at low risk. The AUC of LH secretion following the first challenge of GnRH was significantly higher in amenorrheic women with a high risk of bulimia in respect with both groups of women at low (P0.034) and medium (P0.009) risk. A similar result was found with FSH AUC following the first GnRH challenge (P0.04 high risk vs low risk and P0.014 high risk vs medium risk). In a multiple regression analysis, the best model predicting the risk of bulimia (BITE total score) included both the LH response to GnRH challenge and BMI. In conclusion, when facing secondary amenorrhea at first consultation, long before a precise pathophysiologic diagnosis of the disease, low basal plasma LH levels and LH response to GnRH challenge may allow one to suspect the presence of abnormal eating pattern of bulimic type.

We have investigated the intranuclear distribution of High-mobility group proteins I/Y by means of immunofluorescent staining employing a variety of cell lines. Confocal scanning laser microscopy analysis revealed that High-mobility group proteins I/Y are present in an intranuclear fibrogranular network and mitotic chromosomes. In Caski, C4I, Flow 2002, and K562 cell lines, High-mobility group proteins I/Y were absent from nucleoli, whereas in HeLa cells they were present in this nuclear domain. Double immunolabeling studies showed that High-mobility group proteins I/Y co-localize with other key nuclear components such as NuMA, SC-35, and TAF(II)70. Nuclear reactivity for High-mobility group proteins I/Y dramatically decreased in apoptotic nuclei of HL-60 human leukemia cells. Our morphological data correlate well with previous biochemical and functional findings obtained by other investigators, who have demonstrated multiple roles for this class of polypeptides. However, they point to the likelihood that High-mobility group proteins I/Y are involved in as yet unidentified functions, most likely in the speckle domains of the nucleus. They also show that conceivably these proteins are also involved in apoptosis.

A rare case of a 10 year old boy presenting with history of lower GI bleeding for one year and acute intestinal obstruction was diagnosed as adenocarcinoma of the colon on exploration. One year follow-up after radical colectomy did not show any recurrence.

Clinical features and serial cerebrospinal fluid (CSF) samples of 50 patients who underwent myelography with iophendylate were studied. Forty two patients (84%) developed one or more features suggestive of meningism lasting for 2-4 days. There was significant rise in the average (mean) CSF counts from 9.81 in the premyelogram sample to 532.6 at the end of 24 hours (p less than 0.001). Both neutrophil and lymphocyte (p less than 000) count increased. At the end of one week, there was significant decrease of total cells in the CSF to 204 (p less than 0.001). Both, neutrophils and lymphocytes decreased. There was significant rise in total proteins in the 24 hours sample, but the fall at one week was not significant statistically. The sugar and chloride values did not change significantly. All CSF samples were negative for bacterial cultures. In conclusion, a significant proportion of the patients undergoing iophendylate myelography develop clinical features suggestive of meningeal irritation and change in the CSF fractions suggestive of meningitis: however these changes are transient and do not warrant institution of chemotherapy or steroids.

The calcium binding epidermal growth factor-like (cbEGF) 12-13 domain pair from human fibrillin-1 was the focus of studies for this dissertation. Various nuclear magnetic resonance (NMR) spectroscopy techniques were employed to analyse the calcium binding, structural and dynamic properties of this pair, and to assess the effects of a disease-causing mutation. Fibrillin-1 is a mosaic protein composed mainly of 43 cbEGF domains arranged as multiple, tandem repeats, and mutations within fibrillin-1 have been linked to Marfan syndrome (MFS). 66% of MFS-causing mutations identified thus far are localised to cbEGF domains, emphasising that the native properties of these domains are critical to the functional integrity of this protein. The cbEGF 12-13 pair is found within the longest run of cbEGFs in fibrillin-1, and many mutations that cluster in this region are associated with the severe, neonatal form of MFS. It is thought that this region may be important for fibrillin-1 assembly into 10- 12nm connective tissue microfibrils. Calcium binding studies of cbEGF 12-13 demonstrated that cbEGF 13 contains the highest affinity site thus far investigated from human fibrillin-1. Comparison with previous results showed that fibrillin-1 cbEGF calcium binding affinity can be significantly modulated by the type of domain which is linked to its N-terminus, and also highlighted the high affinity of the "neonatal" region. The NMR solution structure of cbEGF 12-13 is a near-linear, rod-like arrangement of two cbEGF domains, with both exhibiting secondary structure characteristic of this domain type. The rod-like arrangement is stabilised by calcium binding by cbEGF 13 and by hydrophobic interdomain packing interactions. This observation supports the hypothesis that all Class I EGF/cbEGF-cbEGF pairs, characterised by a single linker residue, possess this rod-like structure. The structure also exhibits additional packing interactions to those previously observed for cbEGF32- 33 from fibrillin-1, which may explain the higher calcium binding affinity of cbEGF13. A model of cbEGF 11-15, created based on structural data for cbEGF 12-13 and a model of cbEGF32-36, has highlighted a potential protein binding interface, which encompasses all known neonatal MFS mutations, as well as a flexible, unstructured loop region of cbEGF 12. Backbone dynamics data confirmed the extended structure of cbEGF 12-13. These data, combined with previous data for cbEGF32-33, highlighted a potential dynamics signature for Class I cbEGF domain pairs. Comparison of data for these pairs also suggested that, in addition to the role of calcium in stabilising rigidity on the picoto millisecond time-scale, calcium affinity may play a key role in determining the anisotropy of cbEGF pairs. Possible dynamic explanations for the variation in calcium binding affinity of cbEGF domains from human fibrillin-1 were also noted. The Gl 127S mutation located in cbEGF 13 of fibrillin-1 causes a mild variant of MFS. NMR studies of the G1127S cbEGF12-13 mutant pair showed that cbEGF12 may chaperone folding of mutant cbEGF 13, an effect most likely mediated through interdomain packing interactions. These studies have also shown that the effects of this mutation are localised to cbEGF13, suggesting that a "partial" MFS phenotype is the result of altered structural, dynamic and/or calcium binding properties of this domain.

In young individuals melatonin administration reduces circulating norepinephrine. Some effects of melatonin are reduced in elderly women and are modulated by gonadal steroids. Accordingly, the influence of melatonin on catecholamine levels was investigated in postmenopausal women without and with oestradiol replacement.Prior to and after 2 months of transdermal oestradiol (50 microg/day), women were studied on two consecutive days, on which they received placebo or 1 mg of melatonin orally in a randomised and double-blind fashion.Fourteen healthy postmenopausal women.Resting levels of epinephrine and norepinephrine and their responses to both a cold stimulus, performed by placing a hand in a basin of water and ice for 2 minutes, and to 10 minutes of upright position (upright test).Prior to oestradiol, melatonin did not modify baseline or stimulated catecholamine levels. In contrast, during oestradiol, melatonin tended to reduce, although not significantly, baseline norepinephrine levels (P = 0.053), and significantly reduced peak values (P = 0.0061) and integrated norepinephrine response (P = 0.0076) to the cold stimulus. Responses of norepinephrine to the upright test were not modified, while those of epinephrine were increased (P = 0.042). During, but not prior to oestradiol replacement, modifications induced by melatonin (melatonin day-placebo day) in the norepinephrine response to the cold (r2 = 0. 457; P = 0.0079) and the upright (r2 = 0.747; P = 0.0001) tests were linearly and inversely related to the responses of the placebo day.Melatonin does not modulate adrenergic activity in postmenopausal women without hormone replacement therapy. Oestradiol replacement restores the capability of melatonin to modulate adrenergic activity, particularly the norepinephrine response to stimuli.

Recent studies have demonstrated the possibility of identifying the sentinel lymph node (sN) as a reliable predictor of axillary lymph node status in both cutaneous melanoma and breast cancer. However, some important issues need further definition: (1) optimization of the technique for intraoperative detection of the sN; (2) predictive value of the sN as regards axillary lymph node status, and (3) reliability of intraoperative histology of the sN. We report our experience in sN mapping in patients with Stage I-II breast cancer, with the aim of assessing: (1) the feasibility of lymphatic mapping with a combined approach (vital blue dye lymphatic mapping and radioguided surgery); (2) the agreement of the intraoperative histologic examination of the sN, by means of hematoxylin and eosin staining with final histology, and (3) the accuracy of sN histology as a predictor of axillary lymph node status.

Children treated for Langerhans cell histiocytosis (LCH) are at risk for short and long term endocrine sequelae, but biological predictors of specific deficits are not well defined. We evaluated the frequency and progression of LCH-related endocrine deficits during long term follow-up and assessed the ability of dynamic endocrine testing to identify patients at risk for late anterior or posterior pituitary hormone dysfunction. The 17 patients (5 males and 12 females) were followed a median of 10 yr after diagnosis of single system (n = 6) or multisystem (n = 11) disease. Study evaluations, performed a median of 4.1 yr after the diagnosis, comprised pituitary hormone responses to the appropriate challenge, 7-h water deprivation test, 3% hypertonic saline infusion, and magnetic resonance imaging (MRI). The six patients with GH deficiency at the time of evaluation had a significantly lower GH response to GHRH than the other patients [median peak, 7.3 vs. 21.5 micrograms/L (P = 0.03); median area under the curve, 4.7 vs. 13.5 micrograms/L (P = 0.03)]; levels in the latter group did not differ significantly from those in 20 age- and sex-matched controls with constitutional or familial short stature. Two patients who had GH responses to GHRH of 20.6 and 23 ng/mL at 2.8 and 9.5 yr of age developed GH deficiency at 6.5 and 11.2 yr of age, respectively. The TSH response to TRH was less than 10 mU/L in three patients, two of whom later developed central hypothyroidism. ACTH and cortisol responses to CRF, and PRL responses to TRH were normal in all cases, and LH and FSH responses to GnRH were compatible with pubertal stage. Abnormalities in arginine vasopressin responses to water deprivation or hypertonic saline infusion were seen only in four patients who had preexisting diabetes insipidus (DI); one patient who later developed DI had normal findings. On standard MRI, posterior pituitary hyperintensity was absent only in the patients with DI. Pituitary stalk thickening was seen in seven patients, including three who did not have DI and had normal arginine vasopressin responses. Delayed posterior and anterior enhancement on dynamic MRI was present in two patients, both of whom later developed central hypothyroidism. Patients with single system disease had a lower 5-yr probability of LCH reactivation (41% vs. 83% for those with multisystem disease; P = 0.21) and a significantly lower risk of endocrine dysfunction (P = 0.007). In this series, dynamic evaluation of pituitary function was not a useful predictor of late endocrine sequelae, with the possible exception of the progressively decreasing TSH response to TRH. Similarly, a standard MRI was not predictive, although dynamic imaging may be informative regarding evolving pituitary hormone deficiency.

In a previous study, we found that the extent of necrosis was the only radiological feature which correlated significantly with survival in patients with glioblastoma. The aim of this paper was to evaluate the variability and prognostic value of the extent of the necrotic area as seen on contrast-enhanced MRI and CT in a larger series. We studied 72 patients who underwent surgical removal of supratentorial glioblastomas and had CT and/or MRI with contrast medium before surgery; 38, all undergoing the same treatment (surgery plus radiotherapy), were followed clinically. Necrosis within the tumour varied greatly, ranging from none (only 1 case) to involvement of 76 % of the tumour. Survival data in the subgroup suggested that only patients with a small area of necrosis (less than 35 % of the tumour) had a significantly longer survival time. When necrosis involved more than 35 % of the mass, patients had a shorter survival time, without any further correlation with the extent of necrosis.

Colonic transit times, in patients with chronic idiopathic constipation, in the past were estimated using radiopaque markers. Currently they are evaluated with colonic scintigraphy, which employs 111In DTPA orally, added to the usual children's breakfast in a 0.05 mCi dose. Anterior views of the abdomen are obtained at 6th, 24th, 30th, 48th, 54th, 72nd hour using a gamma camera on a 128 x 128 matrix and stored on hard disk. These images are processed in successive times, and the colon is divided in three main segments: right-, left- and recto-sigmoid-colon. Total and segmental percentage retentions are evaluated in each interval time. 58 children (35 males and 23 females), aged 1-12 years (mean 8.13), referred for chronic idiopathic constipation at Pediatric Surgery Department of Siena, were studied between January 1990 and September 1996. This group was compared with a control group formed by 15 patients (9 males and 6 females) aged 3-14 years (mean 8.53). Cutoff values, obtained in this control group, allowed us to distinguish, among the 58 children with idiopathic constipation, 6 symptomatic patients with normal colonic transit times and 52 symptomatic patients with pathologic ones. In this last group the evaluation of segmentary colonic transit times allowed us to identify 13 patients (25%) with increased right colonic transit time, 19 (36.5%) with increased left colonic transit time and 20 (38.5%) with increased recto-sigmoidal colonic transit time. Statistical survey allowed to distinguish significantly pathological subjects from control group ones.