Fractionated Stereotactic Radiation Therapy for Pituitary Adenomas: An alternative escalating protocol of hypofractionated stereotactic radiotherapy delivering 35Gy in 5 fractions.

PURPOSE: Evaluate efficacy and toxicity of hypofractionated stereotactic radiotherapy (HSRT) for patients treated for pituitary adenoma (PA) with an alternative HSRT escalating protocol delivering 35Gy in 5 fractions. MATERIAL AND METHODS: From June 2007 to March 2017, 29 patients with pituitary adenoma were treated in Antoine Lacassagne Cancer Centre with an alternative HSRT protocol. Prescribed dose was 35Gy in 5 fractions of 7Gy. Radiographic responses were assessed by annual MRI. Hormone blood samples were evaluated each year after HSRT. RESULTS: A total of 29 patients aged between 23 and 86 years (median 54 years) were included. Twelve patients received HSRT for recurrent cases and 12 received postoperative adjuvant HSRT, 5 patients did not have surgery. After a median follow-up period of 47 months local control rate was 96%. One patient presented an out-field tumor regrowth 73 months after HSRT. The majority of PA were endocrine-active (18 patients, 62%). After HSRT, 8 patients (44%) presented complete response on initial secretion, 4 patients (23%) presented partial response on initial secretion. Four patients (14%) presented grade 2 or more acute radiation toxicities. One grade 4 visual disorder was observed for one patient. CONCLUSIONS: HSRT delivering 35Gy in 5 fractions represents a feasible treatment and shows promising results to reduce hormonal overproduction and to improve local control in PA.

Rehabilitation of a hemiplegic patient with cardiac assistive device.

INTRODUCTION: Possible admission to a PRM unit of a hemiplegic patient equipped with a left ventricular assistance device (LVAD) may constitute a cause for concern. We are reporting our observation on the subject. OBSERVATION: A 30-year-old hemiplegic patient presented with left hemiparesis secondary to a right middle cerebral artery (MCA) ischemic stroke having occurred during cardiopulmonary arrest. Persistence of major left ventricle dysfunction necessitated installation on 8 November 2011 of a mono-ventricular HEART-MATE II assistive device. Possible later recourse to cardiac transplantation would depend on clinical development. When admitted to a PRM unit on 18 January 2012, the patient presented with left hemiparesis and cognitive disorders. Virtually all members of the attendant medical and paramedical team were given instruction on the functioning of electrical power assistance systems. In spite of the complexity of the logistics, and notwithstanding the difficulty of managing potentially worrisome medical problems, multidisciplinary rehabilitation efforts were successful. The patient's improved condition led to the decision to undertake heart transplantation, which was carried out on 27 October 2012. DISCUSSION AND CONCLUSION: This observation illustrates the undeniable role of PRM in decision-making and, more generally, in the opportunities that may arise in sensitive and challenging situations.

Reconstruction of 12 MV bremsstrahlung spectra from measured transmission data by direct resolution of the numeric system AF = T.

An investigation of x-ray spectral reconstruction from transmission data by direct resolution of the matrix system A*F = T (using spectral algebra formalism) has been previously presented. The resolution has been done with simulated spectrum. In this paper, the method on a real case of a 12 MV photon beam was tested. A special study of the setup has been made to estimate and reduce the experimental errors that could alter the results. In order to convert F(E) (a fraction of the signal due to a photon of energy E) into photon fluence phi (E), the chamber energy response R(E) has been studied and an approximated analytical function for its representation was proposed. Spectra reconstructed from different transmission data using different attenuators, buildup caps, and ionization chambers have been compared to verify the uniqueness of the reconstructed spectra. To test the validity of the results, dosimetric values, such as Depth Dose Data have been calculated, from our spectrum, using a specific code developed by Kosunen et al. The results show a good agreement between the measured and calculated data.

Simulation of x-ray spectral reconstruction from transmission data by direct resolution of the numeric system AF = T.

X-ray spectral reconstruction from transmission data was investigated by direct resolution of the matrix system A*F = T using spectral algebra. Theoretical, numerical, and physical conditions were studied to obtain the physical solution of the problem. It is shown why the least-square-fitting methods may not give good results for high energy photon spectra above several MeV. The proposed method does not need a preshaped starting spectrum. Simulation studies have been made with arbitrary but realistic spectra of different shapes and maximum energies simulating the reality and using different materials as attenuator like carbon, aluminum, and even water. Conditions on the attenuator choice to obtain the physical solution of the system are given. The reconstruction method provides good results in the radiotherapy energy range despite measurement errors. The computation is quick and implementable on a personal computer with a mathematical coprocessor.