Frequency and intensity of [18F]-PSMA-1007 uptake after COVID-19 vaccination in clinical PET

Objectives: To assess the frequency and intensity of [18F]-PSMA-1007 axillary uptake in lymph nodes ipsilateral to COVID-19 vaccination with BNT162b2 (Pfizer-BioNTech) or mRNA-1273 (Moderna) in patients with prostate cancer referred for oncological [18F]-PSMA PET/CT or PET/MR imaging. Methods: One hundred twenty six patients undergoing [18F]-PSMA PET/CT or PET/MR imaging were retrospectively included. [18F]-PSMA activity (SUVmax) of ipsilateral axillary lymph nodes was measured and compared with the non-vaccinated contralateral side-and with a non-vaccinated negative control group. [18F]-PSMA active lymph node metastases were measured to serve as quantitative reference. Results: There was a significant difference in SUVmax in ipsilateral and compared to contralateral axillary lymph nodes in the vaccination group (n = 63, p < 0.001) and no such difference in the non-vaccinated control group (n = 63, p = 0.379). Vaccinated patients showed mildly increased axillary lymph node [18F]-PSMA uptake as compared to non-vaccinated patients (p = 0.03). [18F]-PSMA activity of of lymph node metastases was significantly higher (p < 0.001) compared to axillary lymph nodes of vaccinated patients. Conclusions: Our data suggest mildly increased [18F]-PSMA uptake after COVID-19 vaccination in ipsilateral axillary lymph nodes. However, given the significantly higher [18F]-PSMA uptake of prostatic lymph node metastases compared to “reactive” nodes after COVID-19 vaccination, no therapeutic and diagnostic dilemma is to be expected. Advances in knowledge: No specific preparations or precautions (e.g., adaption of vaccination scheduling) need to be undertaken in patients undergoing [18F]-PSMA PET imaging after COVID-19 vaccination.

Online learning in proton radiation therapy: the future in the post-Covid-19 pandemic era?

Objective: The Covid-19 pandemic placed unprecedented strain on medical education and led to a vast increase in online learning. Subsequently, the XXXX International Proton School moved from face-to-face to online. Delegate feedback and current literature were studied to determine benefits, challenges, and potential solutions, for online proton therapy education. Methods: The course was converted to a six-week online course with twice weekly two-hour sessions. Feedback was studied pre, during, and post course regarding demographics, learning objectives, proton therapy knowledge, ease of engagement, technical difficulties, and course format. Statistical analyses were performed for proton therapy knowledge pre and post course. Results: An increase in delegate attendance was seen with increased international and multidisciplinary diversity. Learner objectives included treatment planning, clinical applications, physics, and centre development. Average learner reported scores of confidence in proton therapy knowledge improved significantly from 3, some knowledge, to 4, adequate knowledge after the course (p<0.0001). There were minimal reported difficulties using the online platform, good reported learner engagement, and shorter twice weekly sessions were reported conducive for learning. Recordings for asynchronous learning addressed time zone difficulties. Conclusions: The obligatory switch to online platforms has catalysed a paradigm shift towards online learning with delegates reporting educational benefit. We propose solutions to challenges of international online education, and a pedagogical model for online proton therapy education. Advances in knowledge: Online education is an effective method to teach proton therapy to international audiences. The future of proton education includes a hybrid of online and practical face-to-face learning depending on the level of cognitive skill required.

Opportunistic diagnosis of osteoporotic vertebral fractures on standard imaging performed for alternative indications

Osteoporotic vertebral fractures (VF) are the most common type of osteoporotic fracture. Patients with VF are at increased risk of hip fractures or additional VFs, both of which contribute to patient morbidity and mortality. Early diagnosis of VFs is essential so patients can be prescribed appropriate medical therapy. Most patients with clinical suspicion for VF have an X-ray of the spine. Many VFs are invisible on X-ray and require further imaging. CT can provide excellent bony detail but uses high doses of ionising radiation. MRI provides excellent soft tissue detail and can distinguish old from new fractures in addition to differentiating osteoporotic VFs from other causes of back pain. Bone scans have a limited role due to poor specificity. The literature suggests that radiologists frequently miss or do not report VFs when imaging is requested for an alternative clinical indication and when there is no clinical suspicion of VF. Common examples include failure to identify VFs on lateral chest x-rays, sagittal reformats of CT thorax and abdomen, lateral localizers on MRI and scout views on CT. Failure to diagnose a VF is a missed opportunity to improve management of osteoporosis and reduce risk of further fractures. This article discusses the role of radiographs, CT, MRI and Bone Scintigraphy in the assessment and recognition of osteoporotic fractures. This article focuses on opportunistic diagnosis of vertebral fractures on imaging studies that are performed for other clinical indications. It does not discuss use of DXA which is a specific imaging modality for osteoporosis.

Radiology and the medical student: do increased hours of teaching translate to more radiologists?

Objectives: The UK has a shortage of Radiologists to meet the increasing demand for radiologic examinations. To encourage more medical students to consider Radiology as a career, increased exposure at undergraduate level has been advocated. The aim of this study was to evaluate if formal Radiology teaching hours at medical school had any association with the number of qualified Radiologists joining the General Medical Council Specialist Register. Methods: Total number of doctors joining the GMC Specialist Register as Clinical Radiologists, and those with a primary medical qualifications awarded in Scotland, was obtained from the GMC (2010–2020). Graduate numbers from all 4 Scottish Medical Schools (2000–2011) were also obtained. Hours of Radiology teaching for medical schools in Scotland were obtained from validated AToMS study. Results: Two hundred and twenty three (6.6%) of 3347 Radiologists added to the GMC Specialist Register between 2010 and 2020 received their primary medical qualification (PMQ) from Scottish Universities. The number of Radiologists from Scottish Universities joining the GMC specialist register was 2.6% of the total number of Scottish Medical Graduates. There was no association between the number of hours (Range 1–30) Radiology was taught to medical students and the number that joined the specialist register as Radiologists (p = 0.54 chi square trend). Conclusion: Increased exposure to Radiology teaching does not influence medical students’ decision to take up Radiology as a career. While continued Radiology exposure remains important, other strategies are required in both the short and long term to ensure radiology services are maintained without detriment to patients. Advances in knowledge: Increased hours of Radiology teaching in medical school was not associated with increased radiologists joining the profession.

Don’t blink: inattentional blindness in radiology report interpretation

Objectives: Medical errors attributable to inattentional blindness (IAB) may contribute to adverse patient outcomes. IAB has not been studied in the context of reviewing written radiological reports. This cross-sectional, deception-controlled study measures IAB of physicians towards an unexpected stimulus while interpreting written radiological reports. Methods: Physicians and residents from multiple fields were asked to interpret four radiology text reports. Embedded in one was an unexpected stimulus (either an abnormally placed medical exam finding or a non-medical quote from the popular television show Doctor Who). Primary outcomes were differences in detection rates for the two stimuli. Secondary outcomes were differences in detection rates based on level of training and specialty. Results: The unexpected stimulus was detected by 47.8% (n = 43) of participants; the non-medical stimulus was detected more often than the medical stimulus (75.0% vs 21.7%, OR 10.8, 95% CI 4.1–28.7; p < 0.0001,). No differences in outcomes were observed between training levels or specialties. Conclusion: Only a minority of physicians successfully detected an unexpected stimulus while interpreting written radiological reports. They were more likely to detect an abnormal non-medical stimulus than a medical stimulus. Findings were independent of the level of training or field of medical practice. Advances in knowledge: This study is the first to show that IAB is indeed present among internal medicine, family medicine, and emergency medicine providers when interpreting written radiology reports.

Volumetric and dosimetric impact of Post-Surgical MRI guided radiotherapy for Glioblastoma: A pilot study

Objectives: Glioblastoma (GBM) radiotherapy (RT) target delineation requires MRI, ideally concurrent with CT simulation (pre-RT MRI). Due to limited MRI availability, <72 h post-surgery MRI is commonly used instead. Whilst previous investigations assessed volumetric differences between post-surgical and pre-RT delineations, dosimetric impact remains unknown. We quantify volumetric and dosimetric impact of using post-surgical MRI for GBM target delineation. Methods: Gross tumour volumes (GTVs) for five GBM patients receiving chemo-RT with post-surgical and pre-RT MRIs were delineated by three independent observers. Planning target volumes (PTVs) and RT plans were generated for each GTV. Volumetric and dosimetric differences were assessed through: absolute volumes, volume-distance histograms, and dose-volume histogram statistics. Results: Post-surgical MRI delineations had significantly (p < 0.05) larger GTV and PTV volumes (median 16.7 and 64.4 cm3 respectively). Post-surgical RT plans, applied to pre-RT delineations, had significantly decreased (p < 0.01) median PTV doses (ΔD99% = −8.1 Gy and ΔD95% = −2.0 Gy). Median organ at risk (OAR) dose increases (brainstem ΔD5% =+0.8, normal brain mean dose =+2.9 and normal brain ΔD10% = 5.3 Gy) were observed. Conclusion: Post-surgical MRI delineation significantly impacted RT planning, with larger normal-appearing tissue volumes irradiated and increased OAR doses, despite a reduced coverage of the pre-RT defined target. Advances in knowledge: We believe this is the first investigation assessing the dosimetric impact of using post-surgical MRI for GBM target delineation. It highlights the potential of significantly degraded RT plans, showing the clinical-need for dedicated MRI for GBM RT.

Assessment of body composition and association with clinical outcomes in patients with lung and colorectal cancer

Objectives: To assess body composition in patients with non-small cell lung cancer (NSCLC) and colorectal cancer using whole body MRI and relate this to clinical outcomes. Methods: 53 patients with NSCLC (28 males, 25 females; mean age 66.9) and 74 patients with colorectal cancer (42 males, 32 females; mean age 62.9) underwent staging whole-body MRI scans which were post-processed to derive fat mass (FM), fat free mass (FFM) and skeletal muscle (SM) indices and SM fat fraction (FF). These were compared between the two cancer cohorts using two-sided t-tests and the chi-squared test. Measurements of body composition were correlated with outcomes including length of hospital stay, metastatic status and mortality. Results: Patients with NSCLC had significantly lower FFM (p = 0.0071) and SM (p = 0.0084) indices. Mean SM FF was greater in patients with NSCLC (p = 0.0124) and was associated with longer hospital stay (p = 0.035). There was no significant relationship between FM, FFM and SM indices and length of hospital stay, metastatic status or mortality. Conclusions: Patients with NSCLC had lower FFM and SM indices than patients with colorectal cancer and greater SMFF, indicating lower SM mass with fatty infiltration. These findings reflect differences in the phenotype of the two groups and suggest patients with lung cancer are more likely to require additional nutritional support. Advances in knowledge: Body composition differs between NSCLC and colorectal cancer. Patients with NSCLC have both a reduced SM mass and greater SM FF suggesting that they are more nutritionally deplete than patients with colorectal cancer.

Are simple verbal instructions sufficient to ensure that bladder volume does not deteriorate prostate position reproducibility during spot scanning proton therapy?

Objectives: The purpose of this study is to investigate whether verbal instructions are sufficient for bladder volume (BV) control not to deteriorate prostate position reproducibility in image-guided spot scanning proton therapy (SSPT) for localized prostate cancer. Methods: A total of 268 treatment sessions in 12 consecutive prostate cancer patients who were treated with image-guided SSPT with fiducial markers were retrospectively analyzed. In addition to strict rectal volume control procedures, simple verbal instructions to void urine one hour before the treatment were used here. The BV was measured by a Bladder Scan just before the treatment and the prostate motion was measured by intraprostatic fiducial markers and two sets of X-ray fluoroscopy images. The correlation between the BV change and prostate motion was assessed by linear mixed-effects models and systematic and random errors according to the reproducibility of the BV. Results: The mean absolute BV change during treatment was from −98.7 to 86.3 ml (median 7.1 ml). The mean absolute prostate motion of the patients in the left-right direction was −1.46 to 1.85 mm, in the cranial-caudal direction it was −6.10 to 3.65 mm, and in the anteroposterior direction −1.90 to 5.23 mm. There was no significant relationship between the BV change and prostate motion during SSPT. The early and late genitourinary and gastrointestinal toxicity was minimal with a minimum follow-up of 4.57 years. Conclusions: Simple verbal instructions about urination was suggested to be sufficient to control the BV not to impact on the prostate motion and clinical outcomes in image-guided SSPT. Careful attention to BV change is still needed when the seminal vesicle is to be treated. Advances in knowledge: Our data demonstrated that there was no apparent relationship between BV changes and prostate position reproducibility and simple verbal instruction about urination could be sufficient for image-guided SSPT.

CT findings in sequel of COVID-19 pneumonia and its complications: a pictorial review

A significant number of patients after initial recovery from COVID-19 continue to experience lingering symptoms of the disease that may last for weeks or even months. Lungs being the most commonly affected organ by COVID-19, bear the major brunt of the disease and thus it is imperative to be aware of the evolution of the pulmonary parenchymal changes over time. CT chest is the imaging modality of choice to evaluate post-COVID lungs. Persistent ground-glass opacities, septal thickening and parenchymal bands, crazy-paving, traction bronchiectasis and consolidation constitute the commonly encountered imaging patterns seen on CT in post COVID-19 lungs. Few vulnerable patients can develop lung fibrosis and show honeycombing on CT. Additionally, many complications like superadded infections (bacterial and fungal), pulmonary thromboembolism and pseudoaneurysm formation are also being reported. In the present pictorial review, we have tried to show the entire CT spectrum of sequelae of COVID-19 pneumonia and commonly associated infections and vascular complications.

Impact of 18F-FDG-PET/CT on Clinical Management in Patients with Cholangiocellular Carcinoma

Objective: To determine the impact of 18F-FDG-PET/CT on clinical management of patients with cholangiocellular carcinoma (CCA). Methods: Patients with CCA undergoing clinically indicated 18F-FDG-PET/CT between 04/2013 and 08/2018 were prospectively included in a local PET/CT registry study. Intended clinical management (“non-treatment” such as watchful-waiting or additional diagnostic tests, and “palliative” or “curative treatment”) was recorded before and after PET/CT. Changes in intended management after PET/CT were analyzed. Results: 27 patients (mean age: 60 years, IQR: 51.5–67.5 years, 56% males) with 43 PET/CT-examinations were included. Intended management changed in 35/43 cases (81.4%) following PET/CT. Major changes (i.e., between “non-treatment” and “treatment” strategies or between a “curative” and “palliative” treatment goal) occurred in 27/43 (62.8%) cases. Before PET/CT, additional imaging and/or biopsy was intended in 21/43 (48.8%) and 9/43 (20.9%) cases, respectively. After PET/CT, further imaging was carried out in one case and imaging-targeted biopsy in eight cases. Although the absolute number of biopsies after PET/CT did not decrease, in only one of these eight cases biopsy had already been planned before PET/CT, whereas in the other eight cases the originally planned biopsies were dispensable after PET/CT. Conclusions: 18F-FDG-PET/CT significantly impacts clinical management of patients with CCA. It guides decisions on treatment strategy (especially curative vs palliative treatment goal) and on additional tests, particularly by helping referring clinicians to avoid unnecessary imaging and by guiding targeted biopsy. Advances in knowledge: Systematic implementation of 18F-FDG-PET/CT may enable a more appropriate and tailored treatment of patients with CCA, especially in cases of suspected recurrence.