Metabolic and magnetic resonance imaging: complementary modalities for the preoperative assessment of lateral pelvic lymph nodes in rectal cancer.

BACKGROUND: The management of lateral pelvic lymph nodes for rectal cancer is a topical and controversial issue. The aim of this study was to assess the relationship between lateral pelvic lymph node features on magnetic resonance imaging (MRI) and positron emission tomography-computed tomography (PET-CT) with oncological outcomes in patients with rectal cancer. METHODS: A retrospective analysis of 284 patients with primary locally advanced rectal cancer treated with neoadjuvant therapy and surgical resection with curative intent between January 2003 and Dec 2018 was undertaken. From this study population, a select cohort of 77 patients with abnormal lateral pelvic lymph nodes on preoperative imaging had imaging re-analysed by radiologists blinded to clinical outcomes. Pre and post neoadjuvant therapy MRI and PET-CT lateral pelvic lymph node features were correlated with oncological outcomes. RESULTS: A lateral pelvic lymph node short axis size ≥5 mm on post neoadjuvant therapy MRI was a significant predictor of worse 3-year local recurrence free survival (HR 8.35, P = 0.001). Lateral pelvic lymph node avidity on post neoadjuvant therapy PET-CT was a significant predictor of worse 3-year distant recurrence free survival (HR 5.62, P = 0.001). No correlation of oncological outcomes with overall survival was identified. CONCLUSION: Lateral pelvic lymph node imaging features on post-neoadjuvant therapy MRI and PET-CT predicted those at risk of rectal cancer recurrence. Further studies are required to confirm these findings that suggest restaging MRI and PET-CT are complementary modalities for the preoperative assessment of lateral pelvic lymph nodes in rectal cancer.

Part 1: Imaging findings of common immune checkpoint inhibitor-related adverse effects.

Over the last decade or so, immunotherapy and in particular immune checkpoint inhibitors have become common in the treatment of numerous cancers and have revolutionised oncology. The unique mechanisms of these agents has resulted in novel tumour response patterns and also new drug-related toxicities, both of which can have specific findings on imaging. The widespread and increasing use of these agents means these findings are now encountered across many radiology practices beyond just specialist oncology units. This pictorial essay aims to describe and illustrate imaging findings associated with common and important immune-related adverse events as a result of treatment with immune checkpoint inhibitors.

Part 2: Imaging findings of uncommon but important immune checkpoint inhibitor-related adverse effects.

Oncology care has significantly changed with the emergence of immunotherapy agents, in particular immune checkpoint inhibitors (ICIs). This has had an immediate effect on imaging, with different radiological tumour responses to treatment compared with conventional chemotherapies, and novel imaging findings due to complications caused by these agents (referred to as immune-related adverse effects, irAEs). Some of the more common irAEs may be familiar, but as the use of ICIs increases to a wider variety of cancers, these complications, and in particular, the less common irAEs, will be encountered more frequently on imaging. It will be increasingly important to be familiar with these uncommon irAEs, particularly since they can be difficult to recognise and distinguish from metastatic disease. The aim of this pictorial essay was to describe and illustrate imaging findings that may be encountered related to uncommon but important irAEs as a result of treatment with immune checkpoint inhibitors.

Primary myelofibrosis: spectrum of imaging features and disease-related complications.

Primary myelofibrosis is a chronic clonal stem cell disorder that results in a build-up of marrow fibrosis and dysfunction, hypermetabolic states, and myeloid metaplasia. The clinical and radiological consequences can be quite diverse and range from the manifestations of osteosclerosis and extramedullary haematopoiesis to thrombohaemorrhagic complications from haemostatic dysfunction. In addition, there is the challenge of identifying less well-recognised sites of extramedullary haematopoiesis and their site-specific complications. The intent of this article is to illustrate the spectrum of primary myelofibrosis as declared though multimodality imaging, with examples of both common and rarer disease manifestations.

Atelectasis and mechanical ventilation mode during conservative oxygen therapy: A before-and-after study.

PURPOSE: The purpose of the study is to assess the effect of a conservative oxygen therapy (COT) (target SpO2 of 90%-92%) on radiological atelectasis and mechanical ventilation modes. MATERIALS AND METHODS: We conducted a secondary analysis of 105 intensive care unit patients from a pilot before-and-after study. The primary outcomes of this study were changes in atelectasis score (AS) of 555 chest radiographs assessed by radiologists blinded to treatment allocation and time to weaning from mandatory ventilation and first spontaneous ventilation trial (SVT). RESULTS: There was a significant difference in overall AS between groups, and COT was associated with lower time-weighted average AS. In addition, in COT patients, change from mandatory to spontaneous ventilation or time to first SVT was shortened. After adjustment for baseline characteristics and interactions between oxygen therapy, radiological atelectasis, and mechanical ventilation management, patients in the COT group had significantly lower "best" AS (adjusted odds ratio, 0.28 [95% confidence interval {CI}, 0.12-0.66]; P=.003) and greater improvement in AS in the first 7 days (adjusted odds ratio, 0.42 [95% CI, 0.17-0.99]; P=.049). Moreover, COT was associated with significantly earlier successful weaning from a mandatory ventilation mode (adjusted hazard ratio, 2.96 [95% CI, 1.73-5.04]; P<.001) and with shorter time to first SVT (adjusted hazard ratio, 1.77 [95% CI, 1.13-2.78]; P=.013). CONCLUSIONS: In mechanically ventilated intensive care unit patients, COT might be associated with decreased radiological evidence of atelectasis, earlier weaning from mandatory ventilation modes, and earlier first trial of spontaneous ventilation.

Clinical applications of 3D T2-weighted MRI in pelvic imaging.

OBJECTIVE: The purpose of this article is to illustrate clinical applications of 3D T2-weighted MRI in pelvic imaging. We review technical considerations of 3D T2-weighted MRI with clinical examples. CONCLUSION: 3D T2-weighted MRI has been increasingly utilized for pelvic applications, including imaging of rectal cancer, prostate cancer, anorectal fistulas and the female pelvis. This relatively rapid technique offers good soft-tissue contrast of the pelvic organs, with potential for more widespread clinical use.

Assessment of snared-loop technique when standard retrieval of inferior vena cava filters fails.

PURPOSE: To identify the success and complications related to a variant technique used to retrieve inferior vena cava filters when simple snare approach has failed. METHODS: A retrospective review of all Cook Günther Tulip filters and Cook Celect filters retrieved between July 2006 and February 2008 was performed. During this period, 130 filter retrievals were attempted. In 33 cases, the standard retrieval technique failed. Retrieval was subsequently attempted with our modified retrieval technique. RESULTS: The retrieval was successful in 23 cases (mean dwell time, 171.84 days; range, 5-505 days) and unsuccessful in 10 cases (mean dwell time, 162.2 days; range, 94-360 days). Our filter retrievability rates increased from 74.6% with the standard retrieval method to 92.3% when the snared-loop technique was used. Unsuccessful retrieval was due to significant endothelialization (n = 9) and caval penetration by the filter (n = 1). A single complication occurred in the group, in a patient developing pulmonary emboli after attempted retrieval. CONCLUSION: The technique we describe increased the retrievability of the two filters studied. Hook endothelialization is the main factor resulting in failed retrieval and continues to be a limitation with these filters.

Associations between glaucomatous visual field loss and participation in activities of daily living.

PURPOSE: This study investigated the association between visual field loss and participation in daily activities in individuals with glaucoma. METHODS: Seventy-nine patients were recruited from the Royal Victorian Eye and Ear Hospital. Visual fields were assessed using the Esterman binocular visual field tests and participation in daily activities was assessed using the Impact of Vision Impairment (IVI) questionnaire. Visual acuity and contrast sensitivity were also measured. RESULTS: There was no independent relationship between visual field loss and IVI score (r = -0.20; P = 0.09), except for the mobility domain (r = 0.25; P = 0.03). Mobility was the most affected domain of the IVI (mean = 1.2). Over a quarter of the patients reported experiencing moderate to severe restriction with mobility activities despite relatively minor binocular field loss. CONCLUSION: Mobility is the area in which glaucoma patients encounter difficulties even when the visual field and visual acuity are relatively good. Questions related to mobility could be asked to identify those patients who need rehabilitation.