Improving Patient Compliance for More Efficient Deep Inspiration Breath Hold Treatment through Innovation and Education

PURPOSE/OBJECTIVE(S)

Visual guidance has been widely proven to improve the reproducibility and stability of Deep Inspiration Breath Hold (DIBH) treatments. Here, we present a quality improvement project by implementing the use of visual guidance in a multi-campus institution to improve clinical efficiency, including the design of a novel mount for the visual aid and the creation of a patient education video to better prepare lung and GI patients for their DIBH treatments.

MATERIALS/METHODS

Prior to institution-wide implementation, the clinical feasibility of utilizing visual guidance for DIBH treatments was determined by a pilot study with 10 lung/GI patients. A commercial visual guidance device was used, which consisted of a tablet-like device, attached to a mount affixed to the treatment couch. The device is positioned over the patient's head, displaying the real-time vertical motion of a block with infrared markers on the patient's abdomen. The original mount for the device locks onto the superior end of the treatment couch, which occupies space used for immobilization devices and limits the number of patients eligible for visual guidance when the isocenter is inferior, as for GI patients. A novel in-house mount was designed to overcome this limitation. Also, a patient education video was created to introduce the concept of DIBH and the visual aid device. Visual guidance is offered at the first treatment; its use is optional, and patients may start or stop using it at any time. If the device is not used, the patient relies on audio coaching from the radiation therapists (RTTs), which is the standard practice in our clinic.

RESULTS

All 10 patients in the pilot who were offered the visual aid used it, found it helpful and continued to use it throughout their treatment, with no issues reported. The median number of fractions for all 10 patients was 5(3-15). The in-house mount was manufactured from 3D printed and machined components. The treatment couch was 3D scanned, and the mount was designed to clamp laterally on the couch top and align with the indexing indentations. The in-house mount is easy to use and is more versatile than the commercial mount, enabling use for patients with inferior isocenters. Prior to treatment, patients were encouraged to view the <3 min long patient education video that consisted of a combination of animation and real-actor content. Verbal instructions for use were also given by RTTs at the first treatment. Upon successful completion of the pilot study, the use of visual guidance was implemented institution-wide across 5 campuses for all lung and GI DIBH patients, being utilized on an average of 14 patients/week.

CONCLUSION

A quality improvement project was developed and successfully implemented to introduce the use of visual guidance for lung and GI DIBH patients at a large institution, improving the efficiency of DIBH treatment for both the patients and RTTs.

Progression-Free Survival in Patients with WHO-2 Meningioma Undergoing Active Surveillance Based on DOTATATE PET Evidence of Gross Total Resection: Prospective Observational Study

PURPOSE/OBJECTIVE(S)

MRI is the standard of care for meningioma radiotherapy planning, but lacks sensitivity for postoperative small volume disease and osseous or parenchymal invasion. NRG-BN003 (NCT03180268) randomizes patients with WHO-2 meningiomas and MRI-determined gross total resection (GTR) to observation or 60 Gy IMRT to the resection bed. More sensitive and specific imaging biomarkers than MRI may improve clinical outcomes in meningioma by limiting unnecessary irradiation of normal tissues and improving radiotherapy targeting. [68Ga]-DOTATATE, a PET radiotracer targeting somatostatin receptor 2 (SSTR2) is a highly sensitive and specific meningioma biomarker. Our dedicated DOTATATE brain PET/MRI and PET/CT protocol allows meningioma differentiation from post-treatment change, using SUV analysis and Patlak modeling. Our prospective IRB-approved observational trial (NCT04081701) has imaged >100 patients with meningioma. In the sub-analysis presented here, we prospectively evaluated PFS in patients with WHO-2 tumors and postoperative GTR as determined by [68Ga]-DOTATATE brain PET/MRI or PET/CT who were managed solely with active surveillance. We hypothesized that the PFS of patients with GTR by PET managed with active surveillance would be higher than reported PFS data for patients with MRI-determined GTR, using NRG-BN003's observation arm (randomized trial comparing observation to fractionated RT) as a reference standard.

MATERIALS/METHODS

From the cohort of >100 patients with SSTR2-positive brain neoplasms enrolled between 9/2019 and 10/2022 and imaged according to our previously published protocol, a sub-cohort of patients were selected with WHO-2 meningioma, postoperative findings of GTR, and postoperative active surveillance with periodic MRI every 3-6 months. Kaplan-Meier survival analysis was performed.

RESULTS

A total of 12 patients met inclusion criteria. Mean patient age was 64 years and 5 (42%) were female. Mean follow up period was 23.4 months (range: 7-38). 83% (10/12) patients underwent postoperative PET/MRI and 17% (2/12) underwent PET/CT. 2 patients (17%) progressed, at 22 and 34 months, respectively; the remainder remain progression-free. Both patients who had progression were successfully salvaged with focal fractionated radiosurgery. Kaplan-Meier analysis demonstrated PFS at almost 3 years to be 75%, which is substantially higher than the reported 3-year PFS of 60% in the literature. Overall survival was 100%.

CONCLUSION

[68Ga]-DOTATATE PET can improve the specificity of imaging-based assessment of the extent of resection of WHO-2 meningiomas, thereby improving clinical outcomes. In this cohort of patients with completely resected WHO-2 meningiomas (as assessed by postoperative gadolinium-enhanced MRI and DOTATATE PET) who are conservatively managed, recurrences have been rare and amenable to radiosurgical salvage.

Cost-Effectiveness Analysis of 68Ga-DOTATATE PET/MRI in Radiotherapy Planning in Patients with Intermediate-Risk Meningioma

BACKGROUND AND PURPOSE

While contrast-enhanced MR imaging is the criterion standard in meningioma diagnosis and treatment response assessment, gallium 68Ga-DOTATATE PET/MR imaging has increasingly demonstrated utility in meningioma diagnosis and management. Integrating 68Ga-DOTATATE PET/MR imaging in postsurgical radiation planning reduces the planning target volume and organ-at-risk dose. However, 68Ga-DOTATATE PET/MR imaging is not widely implemented in clinical practice due to higher perceived costs. Our study analyzes the cost-effectiveness of 68Ga-DOTATATE PET/MR imaging for postresection radiation therapy planning in patients with intermediate-risk meningioma.

MATERIALS AND METHODS

We developed a decision-analytical model based on both recommended guidelines on meningioma management and our institutional experience. Markov models were implemented to estimate quality-adjusted life-years (QALY). Cost-effectiveness analyses with willingness-to-pay thresholds of $50,000/QALY and $100,000/QALY were performed from a societal perspective. Sensitivity analyses were conducted to validate the results. Model input values were based on published literature.

RESULTS

The cost-effectiveness results demonstrated that 68Ga-DOTATATE PET/MR imaging yields higher QALY (5.47 versus 5.05) at a higher cost ($404,260 versus $395,535) compared with MR imaging alone. The incremental cost-effectiveness ratio analysis determined that 68Ga-DOTATATE PET/MR imaging is cost-effective at a willingness to pay of $50,000/QALY and $100,000/QALY. Furthermore, sensitivity analyses showed that 68Ga-DOTATATE PET/MR imaging is cost-effective at $50,000/QALY ($100,000/QALY) for specificity and sensitivity values above 76% (58%) and 53% (44%), respectively.

CONCLUSIONS

68Ga-DOTATATE PET/MR imaging as an adjunct imaging technique is cost-effective in postoperative treatment planning in patients with meningiomas. Most important, the model results show that the sensitivity and specificity cost-effective thresholds of 68Ga-DOTATATE PET/MR imaging could be attained in clinical practice.

Association between atherogenic lipids and GnRH agonists for prostate cancer in men with T2DM: a nationwide, population-based cohort study in Sweden

BACKGROUND

Gonadotropin-releasing hormone agonists (GnRH) used in prostate cancer (PCa) are associated with atherogenic dyslipidaemia. It can be assumed that GnRH need to be used with greater caution in men with type 2 diabetes mellitus (T2DM). This study investigated association of GnRH with atherogenic lipids (AL) in PCa men with T2DM.

METHODS

Two cohorts including 38,311 men with 11 years follow-up based on Swedish national registers were defined (PCa-Exposure cohort and GnRH-Exposure cohort). Based on European guidelines on cardiovascular diseases (CVD), primary outcomes were defined as: 1.0 mmol/L increase in AL and lipid-lowering therapy (LLT) intensification. We used Cox proportional-hazards models and Kaplan-Meier curves to assess the association.

RESULTS

There was an association between GnRH and increased AL (i.e., triglyceride, PCa-Exposure cohort: HR 1.77, 95% CI 1.48-2.10; GnRH-Exposure cohort: HR 1.88, 95% CI 1.38-2.57). There was also an association between PCa diagnosis and increased AL. In contrast, no association between LLT intensification and GnRH was found.

CONCLUSION

In this large population-based study, men with T2DM on GnRH for PCa had an increased risk of increased atherogenic lipids. These results highlight the need to closely monitor lipids and to be ready to intensify lipid-lowering therapy in men with T2DM on GnRH for PCa.

The KNee OsteoArthritis Prediction (KNOAP2020) challenge: An image analysis challenge to predict incident symptomatic radiographic knee osteoarthritis from MRI and X-ray images

OBJECTIVES

The KNee OsteoArthritis Prediction (KNOAP2020) challenge was organized to objectively compare methods for the prediction of incident symptomatic radiographic knee osteoarthritis within 78 months on a test set with blinded ground truth.

DESIGN

The challenge participants were free to use any available data sources to train their models. A test set of 423 knees from the Prevention of Knee Osteoarthritis in Overweight Females (PROOF) study consisting of magnetic resonance imaging (MRI) and X-ray image data along with clinical risk factors at baseline was made available to all challenge participants. The ground truth outcomes, i.e., which knees developed incident symptomatic radiographic knee osteoarthritis (according to the combined ACR criteria) within 78 months, were not provided to the participants. To assess the performance of the submitted models, we used the area under the receiver operating characteristic curve (ROCAUC) and balanced accuracy (BACC).

RESULTS

Seven teams submitted 23 entries in total. A majority of the algorithms were trained on data from the Osteoarthritis Initiative. The model with the highest ROCAUC (0.64 (95% confidence interval (CI): 0.57-0.70)) used deep learning to extract information from X-ray images combined with clinical variables. The model with the highest BACC (0.59 (95% CI: 0.52-0.65)) ensembled three different models that used automatically extracted X-ray and MRI features along with clinical variables.

CONCLUSION

The KNOAP2020 challenge established a benchmark for predicting incident symptomatic radiographic knee osteoarthritis. Accurate prediction of incident symptomatic radiographic knee osteoarthritis is a complex and still unsolved problem requiring additional investigation.

High-Resolution T2-Weighted Imaging for Surveillance in Postoperative Vestibular Schwannoma: Equivalence with Contrast-Enhanced T1WI for Measurement and Surveillance of Residual Tumor

BACKGROUND AND PURPOSE

Patients with surgically resected vestibular schwannoma will undergo multiple postoperative surveillance examinations, typically including postcontrast sequences. The purpose of this study was to compare high-resolution T2WI with gadolinium T1WI in the postoperative assessment of vestibular schwannoma.

MATERIALS AND METHODS

This was a retrospective study of patients with a history of resected vestibular schwannoma at a single institution. High-resolution T2WI and gadolinium T1WI were independently evaluated for residual disease. In addition, 3D and 2D measurements were performed in the group of patients with residual tumor. Statistical analysis was performed to evaluate the agreement between sequences on the binary assessment (presence/absence of tumor on initial postoperative examination) and to evaluate the equivalence of measurements for the 2 sequences on 3D and 2D quantitative assessment in individuals with residual disease.

RESULTS

One hundred forty-eight patients with retrosigmoid-approach resection of vestibular schwannomas were included in the final analysis. There was moderate-to-substantial agreement between the 2 sequences for the evaluation of the presence versus absence of tumor (Cohen κ coefficient = 0.78; 95% CI, 0.68-0.88). The 2 sequences were significantly equivalent for 2D and 3D quantitative assessments (short-axis P value = .021; long-axis P value = .015; 3D P value = .039).

CONCLUSIONS

In this retrospective study, we demonstrate moderate-to-substantial agreement in the categoric assessment for the presence versus absence of tumor and equivalence between the 2 sequences for both 2D and volumetric tumor measurements as performed in the subset of patients with measurable residual. On the basis of these results, high-resolution T2WI alone may be sufficient for early postoperative imaging surveillance in this patient population.

Thrombospondin 2 is a Functional Predictive and Prognostic Biomarker for Triple-Negative Breast Cancer Patients With Neoadjuvant Chemotherapy

Background: Triple-negative breast cancer (TNBC) is characterized by a more aggressive biological behavior and unfavorable outcome. Circulating and histological expression of THBS2 has been demonstrated to be a novel diagnostic and prognostic biomarker in patients with various types of tumors. However, few studies have evaluated the predictive and prognostic value of THBS2 in TNBC specifically.

Methods: In total, 185 triple-negative breast cancer patients (TNBC) with preoperative neoadjuvant chemotherapy were enrolled in this study. Serum THBS2 (sTHBS2) level was measured both prior to the start of NAC and at surgery by enzyme-linked immunosorbent assay (ELISA). Histological THBS2 (hTHBS2) expression in patients with residual tumors was evaluated by immunohistochemistry (IHC) staining method. Correlations between variables and treatment response were studied. Kaplan-Meier plots and Cox proportional hazard regression model were applied for survival analysis. Functional activities of THBS2 in TNBC cells were determined by CCK-8 assay, colony formation, wound healing, and transwell assay.

Results: Of the 185 patients, 48 (25.9%) achieved pathological complete response (pCR) after completion of NAC. Elevated pCR rates were observed in patients with a lower level of sTHBS2 at surgery and higher level of sTHBS2 change (OR = 0.88, 95%CI: 0.79–0.98, p = 0.020 and OR = 1.12, 95%CI: 1.02–1.23, p = 0.015, respectively). In survival analysis, hTHBS2 expression in residual tumor was of independent prognostic value for both disease-free survival (HR = 2.21, 95%CI = 1.24–3.94, p = 0.007) and overall survival (HR = 2.07, 95%CI = 1.09–3.92, p = 0.026). For functional studies, THBS2 was indicated to inhibit proliferation, migration, and invasion abilities of TNBC cells in vitro.

Conclusion: Our findings confirmed the value of serum THBS2 level to predict pCR for TNBC patients and the prognostic performance of histological THBS2 expression in non-pCR responders after NAC. THBS2 might serve as a promising functional biomarker for patients with triple-negative breast cancer.

Association of Gonadotropin-Releasing Hormone Agonists for Prostate Cancer With Cardiovascular Disease Risk and Hypertension in Men With Diabetes

IMPORTANCE

Men with type 2 diabetes have an increased risk of cardiovascular disease (CVD). Meanwhile, gonadotropin-releasing hormone (GnRH) agonists used in prostate cancer (PCa) are associated with increased risk of CVD.

OBJECTIVE

To evaluate the association between GnRH agonist use, PCa diagnosis per se, and CVD risk in men with type 2 diabetes.

DESIGN, SETTING, AND PARTICIPANTS

This nationwide population-based cohort study identified men with type 2 diabetes by use of data in the Prostate Cancer Data Base Sweden version 4.1 and the Swedish National Diabetes Register, with longitudinal data from 2006 to 2016. These data were used to create 2 cohorts, 1 including men with and without PCa and the other including men with PCa who received and did not receive GnRH agonists. Data analysis was conducted from January 2006 to December 2016.

EXPOSURES

Treatment with GnRH agonists and PCa diagnosis were the primary exposures.

MAIN OUTCOMES AND MEASURES

Primary outcome was a 10% increase in predicted 5-year CVD risk score. Secondary outcome was worsening hypertension as defined by the European Society of Hypertension Guidelines. Cox proportional hazards regression models were used to analyze the association.

RESULTS

The PCa exposure cohort included 5714 men (median [IQR] age, 72.0 [11.0]), and the non-PCa cohort included 28 445 men without PCa (median [IQR] age, 72.0 [11.0]). The GnRH agonist-exposure cohort included 692 men with PCa who received a GnRH agonist, compared with 3460 men with PCa who did not receive a GnRH agonist. Men with PCa receiving GnRH agonists had an increased estimated 5-year CVD risk score compared with men without PCa (hazard ratio [HR], 1.25; 95% CI, 1.16-1.36) and compared with men with PCa not receiving GnRH agonists (HR, 1.53; 95% CI, 1.35-1.74). Men receiving GnRH agonists had decreased blood pressure compared with men without PCa (HR, 0.70; 95% CI, 0.61-0.80) and compared with men with PCa not receiving GnRH agonists (HR, 0.68; 95% CI, 0.56-0.82).

CONCLUSIONS AND RELEVANCE

In this population-based cohort study, there was an increased risk of CVD in men with type 2 diabetes who received a GnRH agonist for PCa. These findings highlight the need to closely control CVD risk factors in men with type 2 diabetes treated with GnRH agonists. The association between GnRH agonist use and decreased blood pressure levels warrants further study.

Precise Measurement of the Thickness of Vaginal Intraepithelial Neoplasia

OBJECTIVES

Although carbon dioxide laser vaporization is frequently used for treating vaginal intraepithelial neoplasia (VaIN), the optimal depth of epithelial destruction with laser vaporization requires elucidation. We aimed to evaluate VaIN depth and better illustrate epithelial destruction during laser vaporization.

MATERIALS AND METHODS

We included 246 women diagnosed with VaIN (low-grade VaIN [VaIN 1], 123 women; high-grade VaIN [VaIN 2/3], 123 women) using colposcopy-directed biopsy at our hospital from January 1, 2019, to April 30, 2020. The thickness of the noninvolved epithelium, if available, was determined. All available data, including cytology and histological information, were recorded. The t test and Pearson χ 2 test were used for statistical analysis. Statistical significance was set at p < .05.

RESULTS

The involved epithelial thicknesses in VaIN 2/3 and VaIN 1 were 0.41 ± 0.21 and 0.40 ± 0.19 mm, respectively, which were both greater than their noninvolved epithelial thickness values (0.17 ± 0.10 and 0.17 ± 0.08 mm, p < .01 and p < .01, respectively). In subgroup comparisons between the VaIN 2/3 and VaIN 1 groups, the involved epithelial thickness did not differ between premenopausal patients, postmenopausal women receiving estrogen, and postmenopausal women who did not receive estrogen ( p > .05). In the VaIN 2/3 group, the lesion thickness in premenopausal was greater than that in postmenopausal women receiving estrogen ( p = .016) and those who were not receiving estrogen ( p = .017).

CONCLUSIONS

The thickness of VaIN is generally less than 1 mm for women of all ages, except in rare cases of visible lesions with papillary hyperplasia.

Changes in community and hospital-based health care use during the COVID-19 pandemic for adults with and without intellectual and developmental disabilities

BACKGROUND

Due to the functional, cognitive and communication impairments associated with intellectual and/or developmental disabilities (IDD), adaptations to service delivery during the COVID-19 pandemic may impact people with IDD differently than others. For community and hospital-based services, this study describes the proportion of adults with and without IDD who used health care in the year pre-COVID-19 and the first year of the pandemic.

METHODS

This retrospective cohort study used linked health administrative databases to identify adults aged 18-105 years with and without IDD using unique encoded identifiers. Counts and proportions of adults who used health care services were reported for the pre-COVID-19 year (16 March 2019 to 14 March 2020) and the first COVID-19 year (15 March 2020 to 15 March 2021).

RESULTS

Across services, the proportion of adults who used services was lower during the first COVID-19 year compared with the year prior, except for virtual physician visits that increased markedly for people with and without IDD. While the proportion of adults who used services was higher for those with IDD compared with those without IDD for both years, differences were greatest for mental health emergency visits and hospitalisations; adults with IDD were 6.3 to 10.9 times more likely to use these services than others with no IDD during the pandemic.

CONCLUSIONS

During the first COVID-19 year in Ontario, Canada, service use decreased for all service types, except for virtual physician visits. In both years, adults with IDD remained more likely to use services than other adults, with the largest differences in use of mental health hospitalisations and mental health emergency department visits.

Prognostic Factors of Stroke-Like Migraine Attacks after Radiation Therapy (SMART) Syndrome

BACKGROUND AND PURPOSE

Prognostic factors of stroke-like migraine attacks after radiation therapy (SMART) syndrome have not been fully explored. This study aimed to assess clinical and imaging features to predict the clinical outcome of SMART syndrome.

MATERIALS AND METHODS

We retrospectively reviewed the clinical manifestations and imaging findings of 20 patients with SMART syndrome (median age, 48 years; 5 women) from January 2016 to January 2020 at 4 medical centers. Patient demographics and MR imaging features at the time of diagnosis were reviewed. This cohort was divided into 2 groups based on the degree of clinical improvement (completely versus incompletely recovered). The numeric and categoric variables were compared as appropriate.

RESULTS

There were statistically significant differences between the completely recovered group (n = 11; median age, 44 years; 2 women) and the incompletely recovered group (n = 9; median age, 55 years; 3 women) in age, months of follow-up, and the presence of steroid treatment at diagnosis (P = .028, .002, and .01, respectively). Regarding MR imaging features, there were statistically significant differences in the presence of linear subcortical WM susceptibility abnormality, restricted diffusion, and subcortical WM edematous changes in the acute SMART region (3/11 versus 8/9, P = .01; 0/11 versus 4/9, P = .026; and 2/11 versus 7/9, P = .022, respectively). Follow-up MRIs showed persistent susceptibility abnormality (11/11) and subcortical WM edematous changes (9/9), with resolution of restricted diffusion (4/4).

CONCLUSIONS

Age, use of steroid treatment at the diagnosis of SMART syndrome, and MR imaging findings of abnormal susceptibility signal, restricted diffusion, and subcortical WM change in the acute SMART region can be prognostic factors in SMART syndrome.

Exploring the association between use of gonadotropin releasing hormones agonists and prostate cancer diagnosis per se and diabetes control in men with type 2 diabetes mellitus: a nationwide, population-based cohort study

BACKGROUND

Gonadotropin Releasing Hormones agonists (GnRH), which are first line treatment for metastatic prostate cancer (PCa), increase risk of type 2 diabetes mellitus (T2DM). This study aims to quantify the association of use of GnRH with diabetes control in PCa men with T2DM.

METHODS

Nationwide population-based cohort study in the Swedish National Diabetes Register and Prostate Cancer data Base Sweden 4.1, on the association between GnRH and diabetes control in T2DM men with PCa by comparing T2DM men with PCa vs. without PCa, as well as comparing T2DM men with PCa on or not on GnRH. The primary exposure was use of GnRH. Worsening diabetes control was the primary outcome, defined as: 1) HbA1c rose to 58 mmol/mol or higher; 2) HbA1c increase by 10 mmol/mol or more; 3) Start of antidiabetic drugs or switch to insulin. We also combined all above definitions. Cox proportional hazards regression was used to analyze the association.

RESULTS

There were 5714 T2DM men with PCa of whom 692 were on GnRH and 28,445 PCa-free men with T2DM with similar baseline characteristics. Diabetes control was worse in men with GnRH vs. PCa-free men (HR: 1.24, 95% CI: 1.13-1.34) as well as compared with PCa men without GnRH (HR:1.58, 95% CI: 1.39-1.80), when we defined the worsening control of diabetes by combining all definitions above.

CONCLUSION

Use of GnRH in T2DM men with PCa was associated with worse glycemic control. The findings highlight the need to closely monitor diabetes control in men with T2DM and PCa starting GnRH.

Prefertilization Exposure of Rainbow Trout Eggs to Per- and Polyfluoroalkyl Substances to Simulate Accumulation During Oogenesis

Aqueous film-forming foams (AFFFs) are used in firefighting and are sources of per- and polyfluoroalkyl substances (PFAS) to the environment through surface runoff and groundwater contamination at defense and transportation sites. Little is known regarding the toxicity and bioaccumulation of newer AFFF formulations containing novel PFAS. To mimic maternal transfer of PFAS, prefertilization rainbow trout eggs were exposed to three PFAS using novel methodologies. Batches of unfertilized oocytes were exposed for 3 h to 0, 0.01, 0.1, 1, or 10 µg/ml separately to perfluorooctanoic acid, perfluorohexanoic acid, or perfluorooctanesulfonic acid in either coelomic fluid or Cortland's solution. After exposure, the gametes were fertilized and rinsed with dechlorinated water. Egg yolk was aspirated from a subset of fertilized eggs for PFAS quantification. Each PFAS was detected in yolks of eggs exposed to the respective PFAS, and yolk concentrations were directly proportional to concentrations in aqueous media to which they were exposed. Exposure in coelomic fluid or Cortland's solution resulted in similar concentrations of PFAS in egg yolks. Ratios of PFAS concentrations in oocytes to concentrations in exposure media (oocyte fluid ratios) were <0.99 when exposed from 0.01 to 10 µg/ml and <0.45 when exposed from 0.1 to 10 µg/ml for both media and all three PFAS, demonstrating that the water solubility of the chemicals was relatively great. Prefertilization exposure of eggs effectively introduced PFAS into unfertilized egg yolk. This method provided a means of mimicking maternal transfer to evaluate toxicity to developing embryos from an early stage. This method is more rapid and efficient than injection of individual fertilized eggs and avoids trauma from inserting needles into eggs. Environ Toxicol Chem 2021;40:3159-3165. © 2021 SETAC.

The importance of patient and public involvement in cancer research: time to create a new job profile

Tweetable abstract Need to add #PPI coordinator to required job profiles in #research: improve research quality, enthuse research team and ensure #patients and their families are the center of our research activities.

Immersive visualisation of intracardiac blood flow in virtual reality on a patient with HLHS

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): NIHR i4i funded 3D Heart project Wellcome/EPSRC Centre for Medical Engineering [WT 203148/Z/16/Z]

onbehalf

3D Heart Project

Background/Introduction: Virtual Reality (VR) for surgical and interventional planning in the treatment of Congenital Heart Disease (CHD) is an emerging field that has the potential to improve planning. Particularly in very complex cases, VR permits enhanced visualisation and more intuitive interaction of volumetric images, compared to traditional flat-screen visualisation tools. Blood flow is severely affected by CHD and, thus, visualisation of blood flow allows direct observation of the cardiac maladaptions for surgical planning. However, blood flow is fundamentally 3D information, and viewing and interacting with it using conventional 2D displays is suboptimal. 

Purpose

To demonstrate feasibility of blood flow visualisation in VR using pressure and velocity obtained from a computational fluid dynamic (CFD) simulation of the right ventricle in a patient with hypoplastic left heart syndrome (HLHS) as a proof of concept.

Methods

 We extend an existing VR volume rendering application to include CFD rendering functionality using the Visualization Toolkit (VTK), an established visualisation library widely used in clinical software for visualising medical imaging data. Our prototype displays the mesh outline of the segmented heart, a slicing plane showing blood pressure on the plane within the heart, and streamlines of blood flow from a spherical source region. Existing user tools were extended to enable interactive positioning, rotation and scaling of the pressure plane and streamline origin, ensuring continuity between volume rendering and CFD interaction and, thus, ease of use. We evaluated if rendering and interaction times were low enough to ensure a comfortable, interactive VR experience. Our performance benchmark is a previous study showing VR is acceptable to clinical users when rendering speed is at least 90 fps.

Results

CFD simulations were successfully rendered, viewed and manipulated in VR, as shown in the Figure. Evaluating performance, we found that visualisation of the mesh and streamlines was at an acceptably high and stable frame rate, over 150fps. User interactions of moving, rotating or scaling the mesh or streamlines origin did not significantly reduce this frame rate. However, rendering the  pressure slicing plane reduced frame rate by an unacceptable degree, to less than 10fps.  

Conclusion

Visualisation of and interaction with CFD simulation data was successfully integrated into an existing VR application. This aids in surgery and intervention planning for defects heavily relying on blood flow simulation, and lays a foundation for a platform for clinicians to test interventions in VR. Pressure plane rendering performance will require significant optimisation, potentially addressed by updating the pressure plane data separately from the main, VR rendering.

Abstract Figure. An example render of CFD simulation

Automatic orientation cues for intuitive immersive interrogation of 3D echocardiographic images in virtual reality using deep learning

Funding Acknowledgements

Type of funding sources: Other. Main funding source(s): NIHR i4i funded 3D Heart Project Wellcome / EPSRC Centre for Medical Engineering (WT 203148/Z/16/Z)

onbehalf

3D Heart Project

Background/Introduction:

In echocardiography (echo), image orientation is determined by the position and direction of the transducer during examination, unlike cardiovascular imaging modalities such as CT or MRI. As a result, when echo images are first shown their display orientation has no external anatomical landmarks, thus the user has to identify anatomical landmarks in the regions of interest to understand the orientation. 

Purpose

To display an anatomical model of a standard heart, automatically aligned to an acquired patient’s 3D echo image - assisting image interpretation by quickly orienting the viewer. 

Methods

 

47 echo datasets from 13 pediatric patients with hypoplastic left heart syndrome (HLHS) were annotated by manually indicating the cardiac axes in both ES and ED volumes. We chose a view akin to the standard four chamber view in healthy hearts as the reference view, showing the AV valves, the right atrium, the left atrium and the hypoplastic ventricle. We then trained a deep convolutional neural network (CNN) to predict the rotation required for re-orientation to the reference view. Three data strategies were explored: 1) using 3D images to estimate orientation, 2) using three orthogonal slices only (2.5D approach) and 3) using the central slice only (2D approach). Three different algorithms were investigated: 1) an orientation classifier, 2) an orientation regressor with mean absolute angle error, and 3) an orientation regressor with geodesic loss. The data was split into training, validation and test sets with a 8:1:1 ratio. The training data was augmented by applying random rotations in the range [−10◦, +10◦] and updating labels accordingly. The model with smallest validation error was applied in tandem with the VR visualisation of the echo volumes. 

Results

Experimental results suggest that a 2.5D CNN classifying discrete integer angles performs best in re-orienting volumetric images to the reference view, with a mean absolute angle error on the test set of 9.0 deg (test set error ranges from 10.8 to 25.9 deg. for other algorithms). An HLHS volumetric data (left) is automatically aligned with the cardiac model (right) using our trained network when loaded in VR as shown in Figure 1. The volume and the model are both cropped at the referencing plane.

Conclusion

A deep learning network to align 3D echo images to a reference view was successfully trained and then integrated  into VR to reorient echo volumes to match a standard anatomical view. This work demonstrates the potential of combining artificial intelligence and VR in medical imaging, although further user study is expected to evaluate its clinical impact.

Caption for Abstract Picture

 The VR user interface informs the user of the 3D echo image orientation, automatically aligning it with an anatomical model, here showing the four chamber apical view.

Abstract Figure. Deep learning model integrated into VR

Metabolite V, an epoxide species is a minor circulating metabolite in humans following a single oral dose of deflazacort

Deflazacort (Emflaza) was approved in the United States in 2017 for the treatment of the Duchenne muscular dystrophy in patients aged 2 years and older. Several deflazacort metabolites were isolated and identified from rats, dogs, monkeys, and humans. Among them, 1ß,2ß-epoxy-3ß-hydroxy-21-desacetyl deflazacort, referred to as Metabolite V, was reported to be one of the major circulating metabolites in humans. However, its quantitative distribution in plasma was not fully characterized. The objective of this study was to determine deflazacort plasma pharmacokinetics, metabolite profiles and their quantitative exposures in humans following a single oral dose. Six healthy male subjects were each administered a single oral dose of 60 mg [14 C]-deflazacort. Plasma and urine were collected and deflazacort metabolites in plasma were quantified by high performance liquid chromatography radio-profiling followed by liquid chromatography-mass spectrometry characterization. Metabolite V was isolated from urine and its structure was further confirmed by nuclear magnetic resonance analysis. These analyses demonstrated that deflazacort was not detectable in plasma; of the eight circulating deflazacort metabolites identified or characterized, the pharmacologically active metabolite 21-desacetyl deflazacort and inactive metabolite 6ß-hydroxy-21-desacetyl deflazacort accounted for 25.0% and 32.9% of the 0-24 hours plasma total radioactivity, respectively, while Metabolite V, an epoxide species, was a minor circulating metabolite, representing only about 4.7% of the total plasma radioactivity.

Brain Imaging of Patients with COVID-19: Findings at an Academic Institution during the Height of the Outbreak in New York City

BACKGROUND AND PURPOSE

A large spectrum of neurologic disease has been reported in patients with coronavirus disease 2019 (COVID-19) infection. Our aim was to investigate the yield of neuroimaging in patients with COVID-19 undergoing CT or MR imaging of the brain and to describe associated imaging findings.

MATERIALS AND METHODS

We performed a retrospective cohort study involving 2054 patients with laboratory-confirmed COVID-19 presenting to 2 hospitals in New York City between March 4 and May 9, 2020, of whom 278 (14%) underwent either CT or MR imaging of the brain. All images initially received a formal interpretation from a neuroradiologist within the institution and were subsequently reviewed by 2 neuroradiologists in consensus, with disputes resolved by a third neuroradiologist.

RESULTS

The median age of these patients was 64 years (interquartile range, 50-75 years), and 43% were women. Among imaged patients, 58 (21%) demonstrated acute or subacute neuroimaging findings, the most common including cerebral infarctions (11%), parenchymal hematomas (3.6%), and posterior reversible encephalopathy syndrome (1.1%). Among the 51 patients with MR imaging examinations, 26 (51%) demonstrated acute or subacute findings; notable findings included 6 cases of cranial nerve abnormalities (including 4 patients with olfactory bulb abnormalities) and 3 patients with a microhemorrhage pattern compatible with critical illness-associated microbleeds.

CONCLUSIONS

Our experience confirms the wide range of neurologic imaging findings in patients with COVID-19 and suggests the need for further studies to optimize management for these patients.