Before performing radiation therapy, radiation oncologists first carefully review medical images of the patient to identify the gross tumour volume, the observable portion of the disease. They then design patient-specific clinical target volumes that include surrounding tissues, since these regions can hide cancerous cells and provide pathways for metastasis.
Known as contouring, this process establishes how much radiation a patient will receive and how it will be delivered. In the case of head and neck cancer, this is a particularly sensitive task due to the presence of vulnerable tissues in the vicinity.
Though it may sound straightforward, contouring clinical target volumes is quite subjective. A recent study from Utrecht University found wide variability in how trained physicians contoured the same patient’s computed tomography (CT) scan, leading some doctors to suggest high-risk clinical target volumes eight times larger than their colleagues.
This inter-physician variability is a problem for patients, who may be over- or under-dosed based on the doctor they work with. It is also a problem for determining best practices, so standards of care can emerge.
Recently, Carlos Cardenas, a graduate research assistant and PhD candidate at The University of Texas MD Anderson Cancer Center in Houston, Texas, and a team of researchers at MD Anderson, working under the supervision of Laurence Court with support from the National Institutes of Health, developed a new method for automating the contouring of high-risk clinical target volumes using artificial intelligence and deep neural networks.
Cardenas’ work focuses on translating a physician’s decision-making process into a computer program. "We have a lot of clinical data and radiation therapy treatment plan data at MD Anderson," he said. "If we think about the problem in a smart way, we can replicate the patterns that our physicians are using to treat specific types of tumours."
In their study, they analysed data from 52 oropharyngeal cancer patients who had been treated at MD Anderson between January 2006 to August 2010, and had previously had their gross tumour volumes and clinical tumour volumes contoured for their radiation therapy treatment.
Cardenas spent a lot of time observing the radiation oncology team at MD Anderson, which has one of the few teams of head and neck subspecialist oncologists in the world, trying to determine how they define the targets.
"For high-risk target volumes, a lot of times radiation oncologists use the existing gross tumour disease and apply a non-uniform distance margin based on the shape of the tumour and its adjacent tissues," Cardenas said. "We started by investigating this first, using simple distance vectors."
Cardenas began the project in 2015 and had quickly accumulated an unwieldy amount of data to analyse. He turned to deep learning as a way of mining that data and uncovering the unwritten rules guiding the experts’ decisions.
The deep learning algorithm he developed uses auto-encoders — a form of neural networks that can learn how to represent datasets — to identify and recreate physician contouring patterns.
The model uses the gross tumour volume and distance map information from surrounding anatomic structures as its inputs. It then classifies the data to identify voxels — three-dimensional pixels — that are part of the high-risk clinical target volumes. In oropharyngeal cancer cases, the head and neck are usually treated with different volumes for high, low and intermediate risk. The paper described automating the target for the high-risk areas. Additional forthcoming papers will describe the low and intermediate predictions.
In addition to potentially reducing inter-physician variability and allowing comparisons of outcomes in clinical trials, a tertiary advantage of the method is the speed and efficiency it offers. It takes a radiation oncologist two to four hours to determine clinical target volumes. At MD Anderson, this result is then peer reviewed by additional physicians to minimize the risk of missing the disease.
Using the Maverick supercomputer at the Texas Advanced Computing Center (TACC), they were able to produce clinical target volumes in under a minute. Training the system took the longest amount of time, but for that step too, TACC resources helped speed up the research significantly.
"If we were to do it on our local GPU [graphics processing unit], it would have taken two months," Cardenas said. "But we were able to parallelize the process and do the optimization on each patient by sending those paths to TACC and that’s where we found a lot of advantages by using the TACC system."

Texas Advanced Computing Centerwww.tacc.utexas.edu/-/an-ai-oncologist-to-help-cancer-patients-worldwide

In pregnancies complicated by foetal congenital heart disease (CHD), global placental perfusion was significantly decreased and regional variation of placental perfusion significantly increased as pregnancies progressed, findings that point to non-invasive imaging providing an early warning of placental dysfunction. A Children’s National Health System research team is thought to be the first to report non-invasive, whole placenta perfusion imaging in utero in a study.
According to the National Heart, Lung and Blood Institute, congenital heart defects are the most common type of birth defect, affecting 8 in 1,000 newborns. Early in pregnancy, the foetal heart follows a parallel developmental course as the placenta, which supplies the growing foetus with oxygen and nutrients while ferrying out waste products. The study authors write that placental arteries are dynamic during pregnancy, remodelling themselves to accommodate increased blood flow as foetuses undergo explosive growth spurts in later stages of pregnancy. If this crucial remodelling does not occur, the placenta may not supply sufficient oxygen and nutrients to the foetus, leading to foetal growth restriction or preeclampsia.
The research team led by Catherine Limperopoulos, Ph.D., enrolled 48 pregnant women who underwent at least one foetal magnetic resonance imaging (MRI) session during their second or third trimester of pregnancy. Thirty-one of the women were healthy volunteers whose mean gestational age was 30 weeks (range: 21 to 39 gestational weeks). Seventeen women were pregnant with foetuses diagnosed with CHD whose mean gestational age was 32 weeks (range: 22 to 38 gestational weeks).
The researchers used velocity-selective arterial spin labelling (VSASL), a powerful MRI technique that directly measures the rate of delivery of arterial blood to organs like the brain. ASL tracks water molecules within the blood as blood flows through arteries, eliminating the need to use a contrast agent. The team was able to distinguish the placenta perfusion contributions by the foetus and the mother.
“In pregnancies complicated by foetal CHD, global placental perfusion significantly decreased and regional variation of placental perfusion significantly increased with advancing gestational age,” says Zungho “Wesley” Zun, Ph.D., the study’s lead author.
“Just like the human brain, heart and kidneys─organs that can commandeer heightened blood flow when needed─the placenta may employ an auto-regulatory mechanism to optimize perfusion,” adds Limperopoulos, director of Children’s Developing Brain Research Laboratory and the study’s senior author. “The early increased global placental profusion in pregnancies complicated by CHD may represent an attempt to correct for insufficient foetal blood flow.”
The research team writes that the findings demonstrate that placental dysfunction due to CHD can be apparent as early as the second trimester of pregnancy using this imaging technology.
“The predictive value of VSASL imaging, which we continue to study, holds the promise of detecting dysfunction before placental abnormalities become irreversible,” Limperopoulos says.
Children’s National Health Systemchildrensnational.org/news-and-events/childrens-newsroom/2018/advanced-mri-can-detect-placental-perfusion-abnormalities-in-pregnancies-complicated-by-fetal-chd

New research has found treating an infected hip replacement in a single stage procedure may be as effective or better than the widely used two-stage procedure. To date no well-designed study has compared these procedures head-to-head to decide if one is better or if they achieve the same results. Hip replacement is a very common operation that is effective at providing pain relief and improving mobility, however, infection can sometimes occur following joint replacement. The findings have wide implications for orthopaedic surgery, the NHS, and health systems worldwide.
The research team, led by the University of Bristol, conducted a study that reviewed patient data from 44 studies to compare the effectiveness of the two types of surgery currently used to treat infections – one-stage and two-stage revisions.
In the two-stage procedure, the existing artificial joint is removed in one operation and the patient is treated for several months with antibiotics.  A new joint is then inserted in a second operation.  In the one-stage procedure, the artificial joint is removed along with all infected tissue and a new one inserted in the same operation.
The study found that the one-stage revision strategy is as good, if not better, as the two-stage strategy. The one-stage strategy may also be better suited for patients with certain types of infection or problems that were previously thought not to be appropriate for this type of surgery.
Dr Setor Kunutsor, Research Fellow from the Musculoskeletal Research Unit at the Bristol Medical School: (THS) and lead researcher, said: “For several decades, the two-stage procedure has been presumed to be more effective than the one-stage. However, it has disadvantages for patients such as having two major surgical procedures, significant pain and limited function between stages, long hospital stays, as well as high healthcare costs. The one-stage strategy has potential advantages for patients which include having only one major surgery, shorter time in hospital, reduced functional impairment, and is less expensive.
“When the research team analysed the collected data, the findings confirmed what we had suspected all along – the one-stage strategy may be as effective as, or better than the two-stage strategy.
Speaking about the study, Co-investigator and Senior Author Mr. Andrew Beswick, also a Research Fellow of the Musculoskeletal Research Unit at the Bristol Medical School: (THS), said: “Our research and the subsequent adoption of the one-stage strategy by surgeons and hospitals, could improve lives, prevent unnecessary deaths, and save money.”
Bristol Universitywww.bristol.ac.uk/news/2018/april/hip-replacement.html

Nova Biomedical is pleased to announce the opening of a new sales and after-sales support subsidiary in Switzerland. The new facility demonstrates Nova’s commitment to the Swiss market and to supporting the strong growth of Nova’s biotechnology and in vitro diagnostic testing platforms.
Located close to Zurich in the canton of Zug, Nova’s new subsidiary is designed to fully support current business and to allow for anticipated future growth. The new subsidiary provides full sales and service support and inventory warehousing.
With the new subsidiary, Nova brings the most advanced technology analytical platform for use in cell culture facilities: FLEX2. FLEX2 offers automated, online sampling for up to 16 cell culture analyses including chemistries, dissolved gases, cell density/viability, and osmolality. The system uses a maintenance-free sensor card, requires only 265 µL of sample, and performs all 16 analyses in 4.5 minutes.
Nova’s line of Stat Profile Prime whole blood analysers are designed for use in both hospital and point-of-care (POC) settings in Switzerland. Prime hospital analysers include the Critical Care System (CCS), Electrolyte System (ES), and Prime Plus, which all feature Prime’s innovative, maintenance-free cartridge and reagent technology that saves time, space, and costs.
Prime CCS offers a comprehensive testing menu of pH, PCO2, PO2, Hct, Na, K, Cl, iCa, Glu, and Lac. Prime Plus combines blood gas, electrolyte, and metabolite testing with co-oximetry for an extensive, 22-test menu that’s ready in about one minute.
The newly launched Allegro system is a fast, simple, capillary blood analyser designed for use in primary care settings such as physician offices. Allegro offers a test panel including HbA1c, lipids, glucose, and creatinine, together with urine albumin and creatinine.
The StatStrip and StatSensor line of handheld, POC meter and test strip analysers provide rapid glucose/ketone, lactate, and creatinine results at the bedside to support clinical decision making.
“We at Nova Biomedical are very excited to welcome our new Switzerland subsidiary to our international team and for the opportunity to continue to bring Nova’s biotechnology and in vitro diagnostic testing technologies to this important European market,” said Andy O’Toole, VP European Operations at Nova Biomedical.
www.novabiomedical.com

Panel of Specialist Speakers Explain Development and Real World Application of CARESTREAM OnSight 3D Extremity System

Visitors to ECR 2018, to be held in Vienna, will have the opportunity to learn more about the development and application of Cone Beam CT imaging and the important benefits it brings to weight bearing exams. The programme for a Satellite Symposium entitled ‘OnSight 3D Extremity System – Point of Care CBCT’, organised by Carestream, will detail the evolution of CBCT; the use of CBCT in clinical and emergency settings; the clinical indications for weight bearing CBCT; different generations of metal artefact reduction algorithms and workflow and usability of the Carestream CBCT system.
The Symposium will be held on the second floor, Room Z of the ACV at 14.00 on Friday March 2. Speakers will include Dr John Carrino MD from Baltimore, US, who will also moderate the session; Dr Xavier Montet from Geneva University Hospital, Switzerland; Dr Thibaut Jacques from Lille, France; Dr Mikael Boesen from Copenhagen, Denmark; Dr Mika Kortesniemi from Helsinki, Finland and Roisin Dobbin-Stacey from Cobalt Health in Cheltenham, UK.
All delegates to ECR will be welcome to this timely seminar and remote delegates will also be able to follow the Symposium online. There will be opportunities to examine the Carestream OnSight CBCT system in closer detail on the Carestream booth, number 405 in Expo X4. Click here for more details of Carestream at ECR.