An experimental demonstration of a new type of proton computed tomography using a novel silicon tracking detector

Radiography and tomography using proton beams promises benefit to image-guidance and treatment planning for proton therapy. A novel proton tracking detector is described and experimental demon- strations at a therapy facility reported. A new type of proton CT reconstructing relative ‘scattering-power’ rather than ‘stopping-power’ is also demonstrated. Notably, this new type of imaging does not require the measurement of the residual energies of the protons. Successful tracking of protons through a thick target (phantom) has demonstrated that the tracker discussed in this paper can provide the precise directional information needed to perform proton radiography and tomography. When synchronized with a range telescope, this could enable the reconstruction of proton CT images of stopping power. Furthermore, by measuring the deflection of many protons through a phantom it was demonstrated that it is possible to reconstruct a new kind of CT image (scattering power) based upon this tracking information alone

[Paraneoplastic syndromes of the central nervous system]

Paraneoplastic syndromes of central nervous system are rare neurologic syndromes caused by cancer but not secondary to metastases. The physiopathologic mechanisms underlying these syndromes are still under debate. We report the biological and clinical features of the most frequent paraneoplastic syndromes involving the central nervous system. Their early clinical identification might be an useful marker of an otherwise unknown visceral malignancy. Furthermore, they might also be suggestive for the particular type of cancer present. Once, therefore, the diagnosis of these paraneoplastic syndromes has been established, an appropriate evaluation for the asymptomatic neoplasm in cancer-free individuals or investigation for the malignancy recurrences in oncologic patients might be performed