Potential of MRI in Assessing Treatment Response After Neoadjuvant Radiation Therapy Treatment in Breast Cancer Patients: A Scoping Review.

The objective of this scoping review is to evaluate the potential of Magnetic Resonance Imaging (MRI) and to determine which of the available MRI techniques reported in the literature are the most promising for assessing treatment response in breast cancer patients following neoadjuvant radiotherapy (NRT). Ovid Medline, Embase, CINAHL, and Cochrane databases were searched to identify relevant studies published from inception until March 13, 2023. After primary selection, 2 reviewers evaluated each study using a standardized data extraction template, guided by set inclusion and exclusion criteria. A total of 5 eligible studies were selected. The positive and negative predictive values for MRI predicting pathological complete response across the studies were 67% to 88% and 76% to 85%, respectively. MRI's potential in assessing postradiotherapy tumor sizes was greater for volume measurements than uni-dimensional longest diameter measurements; however, overestimation in surgical tumor sizes was observed. Apparent diffusion coefficient (ADC) values and Time to Enhance (TTE) was seen to increase post-NRT, with a notable difference between responders and nonresponders at 6 months, indicating a potential role in assessing treatment response. In conclusion, this review highlights tumor volume measurements, ADC, and TTE as promising MRI metrics for assessing treatment response post-NRT in breast cancer. However, further research with larger cohorts is needed to confirm their utility. If MRI can accurately identify responders from nonresponders to NRT, it could enable a more personalized and tailored treatment approach, potentially minimizing radiation therapy related toxicity and enhancing cosmetic outcomes.

Insights into the effects of Friedreich ataxia on the left ventricle using T1 mapping and late gadolinium enhancement.

BACKGROUND: The left ventricular (LV) changes which occur in Friedreich ataxia (FRDA) are incompletely understood. METHODS: Cardiac magnetic resonance (CMR) imaging was performed using a 1.5T scanner in subjects with FRDA who are homozygous for an expansion of an intron 1 GAA repeat in the FXN gene. Standard measurements were performed of LV mass (LVM), LV end-diastolic volume (LVEDV) and LV ejection fraction (LVEF). Native T1 relaxation time and the extracellular volume fraction (ECV) were utilised as markers of left ventricular (LV) diffuse myocardial fibrosis and late gadolinium enhancement (LGE) was utilised as a marker of LV replacement fibrosis. FRDA genetic severity was assessed using the shorter FXN GAA repeat length (GAA1). RESULTS: There were 93 subjects with FRDA (63 adults, 30 children, 54% males), 9 of whom had a reduced LVEF (<55%). A LVEDV below the normal range was present in 39%, a LVM above the normal range in 22%, and an increased LVM/LVEDV ratio in 89% subjects. In adults with a normal LVEF, there was an independent positive correlation of LVM with GAA1, and a negative correlation with age, but no similar relationships were seen in children. GAA1 was positively correlated with native T1 time in both adults and children, and with ECV in adults, all these associations independent of LVM and LVEDV. LGE was present in 21% of subjects, including both adults and children, and subjects with and without a reduced LVEF. None of GAA1, LVM or LVEDV were predictors of LGE. CONCLUSION: An association between diffuse interstitial LV myocardial fibrosis and genetic severity in FRDA was present independently of FRDA-related LV structural changes. Localised replacement fibrosis was found in a minority of subjects with FRDA and was not associated with LV structural change or FRDA genetic severity in subjects with a normal LVEF.

The current and future role of the MRI radiographer in radiation oncology: A collaborative, experiential reflection on the Australian rollout of dedicated MRI simulators.

Magnetic Resonance Imaging (MRI) has proven value in radiotherapy treatment planning (RTP). MRI provides excellent soft tissue contrast, and improves lesion detection, definition and extent, allowing for increased conformal treatment. Recent installation of dedicated MRI simulators and MRI-guided linear accelerators (MR Linacs) within radiation oncology departments has led to a sudden and rapid expansion in the scope of practice for many radiation therapists and MRI radiographers. The lack of current recommendations, guidelines and credentialing for both MRI radiographers and radiation therapists working within these atypical MRI environments poses a significant challenge for the education and training of staff, and the safe operation of these units. This commentary discusses current pathways for radiographers and radiation therapists entering the emerging field of MRI-guided radiation oncology, and the future role of the MRI radiographer in addressing the unique issues found in non-standard MRI environments. The authors draw on their collective experience as MRI radiographers assisting the rollout of dedicated MRI simulators in radiation oncology departments across Australia and reflect on the need for close collaboration between radiographers, radiation therapists and their respective departments. There is also a critical role for professional bodies to play in supporting existing and future roles in MRI and recognising advanced practitioner scope of practice.

Prediction of compliance with MRI procedures among children of ages 3 years to 12 years.

BACKGROUND: A number of children are unable to comply with an MRI procedure and require general anesthetic. However, we lack information about which factors are associated with MRI compliance in young children. OBJECTIVE: To determine the strongest predictors of MRI compliance, focusing on variables that can be easily rated by patients' parents. MATERIALS AND METHODS: A sample of 205 children ages 3-11 years (mean age 6.6 years) who were at risk of non-compliance were recruited from a children's hospital. Their parents completed a behavior assessment scale for children as well as a questionnaire that assessed their expectations of compliance and perception of their child's typical medical compliance. The children subsequently completed a mock MRI with an educational play therapist and a clinical MRI, with the quality of the scan scored by the MRI technologist. RESULTS: Overall, 88.3% of children complied with the clinical scan and achieved diagnostic images, with age unrelated to compliance in this well-prepared patient group. The strongest predictors of MRI compliance were parental expectations and ratings of how well the child typically copes with medical procedures. Non-compliance was related to child attention problems and to poor adaptability among children. A total of 64 preschool-age children (91.4%) and 110 school-age children (95.7%) were correctly classified as compliant or non-compliant based on these predictor variables. CONCLUSION: A child's temperament, medical experiences and parental expectations provide important information in predicting which children successfully comply with an MRI procedure and which require general anesthesia. Further study is needed to explore the utility of these variables in predicting compliance at sites that do not have access to an MRI simulator.

Cardiac magnetic resonance imaging prior to bidirectional cavopulmonary connection in hypoplastic left heart syndrome.

BACKGROUND: Recent evidence has suggested that haemodynamic information obtained from cardiac catheterisation is not essential in pre-operative assessment of children with hypoplastic left heart syndrome (HLHS) undergoing Bidirectional Cavopulmonary Connection (BCPC). Therefore our unit changed to cardiac Magnetic Resonance Imaging (MRI) in 2006. We aimed to compare peri-operative outcomes before and after this change. METHODS: Children with HLHS who underwent BCPC between 2004 and 2008 were identified. Data were collected regarding pre-operative findings and peri-operative outcomes. RESULTS: Forty patients were identified-catheterisation (n=21), MRI (n=19). Catheterisation patients were older at the time of BCPC (114.9+/-22.7 days vs. 95.4+/-11 days: p value 0.002), with no other differences in baseline data. Two patients required cardiopulmonary resuscitation during catheterisation; with no adverse events during MRI. Cardiopulmonary bypass time, ventilation time, inotrope score, and intensive care unit stay were similar. Length of hospital stay and oxygen saturations at discharge were also not significantly different. CONCLUSIONS: We have demonstrated that post-operative course and outcomes are similar in patients with HLHS who had MRI or catheterisation as their pre-BCPC investigation. Additionally the complementary data provided by echocardiography and MRI safely provides sufficient anatomic and functional information with which to plan the BCPC.