How Imaging Advances Are Defining the Future of Precision Radiation Therapy.

Radiation therapy is fundamental in the treatment of cancer. Imaging has always played a central role in radiation oncology. Integrating imaging technology into irradiation devices has increased the precision and accuracy of dose delivery and decreased the toxic effects of the treatment. Although CT has become the standard imaging modality in radiation therapy, the development of recently introduced next-generation imaging techniques has improved diagnostic and therapeutic decision making in radiation oncology. Functional and molecular imaging techniques, as well as other advanced imaging modalities such as SPECT, yield information about the anatomic and biologic characteristics of tumors for the radiation therapy workflow. In clinical practice, they can be useful for characterizing tumor phenotypes, delineating volumes, planning treatment, determining patients' prognoses, predicting toxic effects, assessing responses to therapy, and detecting tumor relapse. Next-generation imaging can enable personalization of radiation therapy based on a greater understanding of tumor biologic factors. It can be used to map tumor characteristics, such as metabolic pathways, vascularity, cellular proliferation, and hypoxia, that are known to define tumor phenotype. It can also be used to consider tumor heterogeneity by highlighting areas at risk for radiation resistance for focused biologic dose escalation, which can impact the radiation planning process and patient outcomes. The authors review the possible contributions of next-generation imaging to the treatment of patients undergoing radiation therapy. In addition, the possible roles of radio(geno)mics in radiation therapy, the limitations of these techniques, and hurdles in introducing them into clinical practice are discussed. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Forensic age estimation in Barcelona: analysis of expert reports issued between 2011 and 2018.

INTRODUCTION: In recent years, there has been a notable increase of migratory movements into Europe with the arrival of not (reliably) documented young individuals within EU-Member States. Accordingly, the need for forensic age assessments likewise increased in order to administratively differentiate along the legally relevant cut-off age of 18 completed years. The objective of our study was to analyse the expert reports of forensic age estimation issued in Barcelona between 2011 and 2018. METHOD: In all cases, data on the medical history, physical examination, radiology of the left hand and orthopantomography were collected. In cases without third molars and a complete ossification of the hand, a CT scan of the clavicles was also performed. RESULTS: A total of 2754 expert reports were evaluated; 96.7% were males, the majority were of North African origin, mainly from Morocco (63.6%), and 19.6% were sub-Saharan Africans; 65.4% had a level of bone maturation corresponding to the last three standards of Greulich and Pyle. Most cases had mineralization of the third molar corresponding to the F, G or H stages of Demirjian. In 85.9%, there was a correspondence between bone and dental age. A total of 28.8% of the subjects were evaluated as being aged over 18 years; 86.2% of North Africans were considered to be younger than 18, and 82% of sub-Saharan Africans were considered to be over 18 years old. CONCLUSIONS: In Barcelona, most of the subjects evaluated were male and North African, and 71.2% of the cases were considered to be minors.

[Intracranial calcifications on MRI]. / Calcificaciones intracraneales. Imagen por RM.

OBJECTIVE: The aim of this study is to show that the magnetic resonance imaging (MRI) findings for intracranial calcifications previously demonstrated at computed tomography (CT) are variable and unspecific. MATERIAL AND METHOD: We present a study of 21 patients with calcified intracranial lesions of different etiologies detected at CT. We analyze the MRI signal characteristics in these lesions in T1- and T2-weighted sequences, taking the cerebral cortex as a reference. RESULTS: The MRI signal of the calcified intracranial lesion was variable. Nevertheless, the most frequent appearance on T1-weighted sequences was areas isointense with the cerebral cortex. The most frequent appearance on T2-weighted sequences was foci of hypointensity. CONCLUSIONS: Intracranial calcifications show variable MRI signal characteristics and have an unspecific appearance, making them difficult to characterize. MRI cannot reliably rule out or determine the presence of calcifications. CT study of intracranial lesions enables calcified lesions to be identified and characterized; therefore, CT is the technique of choice for the study of calcified lesions.

Calcificaciones intracraneales. Imagen por RM / Intracranial calcifications on MRI

Objetivo. El objetivo del estudio fue demostrar la variabilidad en la apariencia de las calcificaciones intracraneales y su inespecificidad en estudios de resonancia magnética (RM) demostradas previamente por tomografía computarizada (TC). Material y método. Presentamos un estudio de 21 pacientes con lesiones intracraneales calcificadas de diferente etiología objetivadas en TC y analizamos las características de señal en RM en el seno de dichas lesiones en secuencias potenciadas en T1 y T2, tomando como referencia la corteza cerebral. Resultados. La señal de las lesiones calcificadas intracraneales fue variable. Sin embargo, la apariencia más frecuente de las calcificaciones intracraneales en estudios de RM en secuencias potenciadas en T1 fue la de áreas isointensas con la corteza cerebral. En las secuencias potencias en T2 la presentación más común de las calcificaciones fue la de focos de hipointensidad. Conclusiones. Las calcificaciones intracraneales presentan características de señal variables en las imágenes de RM, siendo su aspecto inespecífico, lo que dificulta la caracterización de lesiones intracraneales. La RM no permite excluir o demostrar con seguridad la presencia de calcificaciones. La TC es la técnica de elección para el estudio de lesiones calcificadas, por tanto, el disponer de una TC craneal en el estudio de lesiones intracraneales permite su identificación y la caracterización de dichas lesiones

Objective. The aim of this study is to show that the magnetic resonance imaging (MRI) findings for intracranial calcifications previously demonstrated at computed tomography (CT) are variable and unspecific. Material and method. We present a study of 21 patients with calcified intracranial lesions of different etiologies detected at CT. We analyze the MRI signal characteristics in these lesions in T1- and T2-weighted sequences, taking the cerebral cortex as a reference. Results. The MRI signal of the calcified intracranial lesion was variable. Nevertheless, the most frequent appearance on T1-weighted sequences was areas isointense with the cerebral cortex. The most frequent appearance on T2-weighted sequences was foci of hypointensity. Conclusions. Intracranial calcifications show variable MRI signal characteristics and have an unspecific appearance, making them difficult to characterize. MRI cannot reliably rule out or determine the presence of calcifications. CT study of intracranial lesions enables calcified lesions to be identified and characterized; therefore, CT is the technique of choice for the study of calcified lesions