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Background After primary maternal cytomegalovirus (CMV) infection during pregnancy, infants are at risk for disease. Methods Factors predictive of infant outcome were analyzed in a database of 304 pregnant women with primary infection. These women were enrolled between 2010 and 2017 and delivered 281 infants, of whom 108 were CMV infected. Long term follow-up occurred for 173 uninfected and 106 infected infants at age 4 years (range, 1–8 years). One hundred fifty-seven women were treated with an average of 2 doses (range, 1–6 doses) of high-dose hyperimmune globulin (HIG: 200 mg/kg/infusion). We used a regression model to define predictors of fetal infection, symptoms at birth, and long-term sequelae; 31 covariates were tested. Results Four factors predicted fetal infection: a 1.8-fold increase (30% vs 56%) in the rate of congenital infection without HIG (adjusted odds ratio [AOR], 5.2; P < .0001), a 1.8-fold increase (32% vs 56%) associated with maternal viral DNAemia prior to HIG administration (AOR, 3.0; P = .002), abnormal ultrasounds (AOR, 59; P = .0002), and diagnosis of maternal infection by seroconversion rather than avidity (AOR, 3.3; P = .007). Lack of HIG and abnormal ultrasounds also predicted symptoms (P = .001). Long-term sequelae were predicted by not receiving HIG (AOR, 13.2; P = .001), maternal infection in early gestation (odds ratio [OR], 0.9; P = .017), and abnormal ultrasounds (OR, 7.6; P < .003). Prevalence and copy/number of DNAemia declined after HIG. Conclusions Maternal viremia predicts fetal infection and neonatal outcome. This may help patient counseling. High-dose HIG may prevent fetal infection and disease and is associated with the resolution of DNAemia.

Measurements performed with the purpose of characterizing the charged secondary radiation for dose release monitoring in particle therapy are reported. Charged secondary yields, energy spectra and emission profiles produced in poly-methyl methacrylate (PMMA) target by 4He and 12C beams of different therapeutic energies were measured at 60 and 90 degree with respect to the primary beam direction. The secondary yields of protons produced along the primary beam path in PMMA target were obtained. The energy spectra of charged secondaries were obtained from time-of-flight information, whereas the emission profiles were reconstructed exploiting tracking detector information. The measured charged secondary yields and emission profiles are in agreement with the results reported in literature and confirm the feasibility of ion beam therapy range monitoring using 12C ion beam. The feasibility of range monitoring using charged secondary particles is also suggested for 4He ion beam., Comment: 19 pages, 26 Figures

The background induced by the high penetration power of the gamma radiation is the main limiting factor of the current Radio-guided surgery (RGS). To partially mitigate it, a RGS with beta+ emitting radio-tracers has been suggested in literature. Here we propose the use of beta- emitting radio-tracers and beta- probes and discuss the advantage of this method with respect to the previously explored ones: the electron low penetration power allows for simple and versatile probes and could extend RGS to tumours for which background originating from nearby healthy tissue makes gamma probes less effective. We developed a beta- probe prototype and studied its performances on phantoms. By means of a detailed simulation we have also extrapolated the results to estimate the performances in a realistic case of meningioma, pathology which is going to be our first in-vivo test case. A good sensitivity to residuals down to 0.1ml can be reached within 1s with an administered activity smaller than those for PET-scans thus making the radiation exposure to medical personnel negligible., 14 pages, 7 figures

Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments is still a matter of research. A possible technique exploits the information provided by single photon emission from nuclear decays induced by the irradiation. This paper reports the measurements of the spectrum and rate of such photons produced from the interaction of a 80 MeV=u fully stripped carbon ion beam at the Laboratori Nazionali del Sud of INFN, Catania, with a Poly-methyl methacrylate target. The differential production rate for photons with energy E > 2 MeV and emitted at 90 o is found to be dNg=(dNCdW) = (2:92 0:19) 10 2 sr 1 .

Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments and the on-line knowledge of the Bragg peak position is still a matter of research. A possible technique exploits the collinear $511\ \kilo\electronvolt$ photons produced by positrons annihilation from $\beta^+$ emitters created by the beam. This paper reports rate measurements of the $511\ \kilo\electronvolt$ photons emitted after the interactions of a $80\ \mega\electronvolt / u$ fully stripped carbon ion beam at the Laboratori Nazionali del Sud (LNS) of INFN, with a Poly-methyl methacrylate target. The time evolution of the $\beta^+$ rate was parametrized and the dominance of $^{11}C$ emitters over the other species ($^{13}N$, $^{15}O$, $^{14}O$) was observed, measuring the fraction of carbon ions activating $\beta^+$ emitters $A_0=(10.3\pm0.7)\cdot10^{-3}$. The average depth in the PMMA of the positron annihilation from $\beta^+$ emitters was also measured, $D_{\beta^+}=5.3\pm1.1\ \milli\meter$, to be compared to the expected Bragg peak depth $D_{Bragg}=11.0\pm 0.5\ \milli\meter$ obtained from simulations.

Proton and carbon ion therapy is an emerging technique used for the treatment of solid cancers. The monitoring of the dose delivered during such treatments is still a matter of research. A possible technique exploits the information provided by single photon emission from nuclear decays induced by the irradiation. This paper reports the measurements of the spectrum and rate of such photons produced from the interaction of a 80 MeV/u fully stripped carbon ion beam at the Laboratori Nazionali del Sud of INFN, Catania, with a Poly-methyl methacrylate target. The differential production rate for photons with energy E > 2 MeV and emitted at 90 degree is found to be $dN_{\gamma}/(dN_C d\Omega)=(2.92\pm 0.19)\times 10^{-2}$sr$^{-1}$.

The radiation used in hadrontherapy treatments interacts with the patient body producing secondary particles, either neutral or charged, that can be used for dose and Bragg peak monitoring and to provide a fast feedback on the treatment plans. Recent results obtained from the authors on simplified setups (mono-energetic primary beams interacting with homogeneous tissue-like target) have already indicated the correlation that exists between the flux of these secondaries coming from the target (e.g. protons and photons) and the position of the primary beam Bragg peak. In this paper, the measurements of charged particle fluxes produced by the interaction of a 220 MeV/u carbon ion beam at GSI, Darmstadt, with a polymethyl methacrylate target are reported. The emission region of protons (p), deuterons (d) and tritons (t) has been characterized using a drift chamber while the particle time-of-flight, used to compute the kinetic energy spectra, was measured with a LYSO scintillator. The energy released in the LYSO crystal was used for particle identification purposes. The measurements were repeated with the setup at 60° and 90° with respect to the primary beam direction. The accuracy on the fragments emission profile reconstruction and its relationship with the Bragg peak position have been studied. Based on the acquired experimental evidence, a method to monitor the dose profile and the position of the Bragg peak inside the target is proposed. © 2014 Institute of Physics and Engineering in Medicine.

Purpose The real-time monitoring of the spread-out Bragg peak would allow the planned dose delivered during treatment to be directly verified, but this poses a major challenge in modern ion beam therapy. A possible method to achieve this goal is to exploit the production of secondary particles by the nuclear reactions of the beam with the patient and correlate their emission profile to the planned target volume position. In this study, we present both the production rate and energy spectra of the prompt-γ produced by the interactions of the 12C ion beam with a polymethyl methacrylate (PMMA) target. We also assess three different Monte Carlo models for prompt-γsimulation based on our experimental data. Methods The experiment was carried out at the GSI Helmholtz Centre for Heavy Ion Research, Germany with a 220 Me V/u 12C ions beam impinging on a 5×5×20 cm3polymethyl methacrylate beam stopping target, with the prompt-γbeing detected by a hexagonallyshaped barium uoride scintillator with a circumscribed radius of 5.4 cm and a length of 14 cm, placed at 60°and 90°with respect to the beam direction. Monte Carlo simulations were carried out with three different hadronic models from the GEANT4 code: binary ion cascade (BIC), quantum molecular dynamics (QMD), and Liege intranuclear cascade (INCL++) Results An experimental prompt-γ yield of 1.06×10-2 sr−1 was measured at 90°.A good agreement was observed between the shapes of the experimental and simulated energy spectra,especially with the INCL++physics list. The prompt-γ yield obtained with this physics list was compatible with the measurement within 2σ, with a relative difference of 26% on average. BIC and QMD physics lists proved to be less accurate than INCL++,with the difference between the measured and simulated yields exceeding 100%.The differences between the three physics lists were ascribed to important discrepancies between the models of the physical processes producing prompt-γ emissions. Conclusion In conclusion, this study provides prompt- γ yield values in agreement with previously published results for different carbon ions energies. his work demonstrates that the INCL++ physics list from GEANT4 is more accurate than BIC and QMD to reproduce prompt-γ emission properties. This article is protected by copyright. All rights reserved.