Phillips Healthcare Research Articles

Evaluation of Hemodynamic Alterations after Flow Diverter Placement using the AneurysmFlowTM tool.

AneurysmFlow (Phillips Healthcare) is the flow measurement tool, utilizing an optical flow-based algorithm from DSA, lacks sufficient published studies. This study aimed to assess the significance of flow velocity changes and the Mean Aneurysm Flow Amplitude (MAFA) ratio in evaluating outcomes following flow-diverting treatments. Between June 2021 and October 2022, 41 patients with 42 aneurysms underwent FDS treatment with AneurysmFlow measu-rement at the Bach Mai Radiology Center. The tool achieved a 90.5% success rate in 38 out of 42 patients. Most aneurysms (89.5%) were small to medium-sized (<10 mm), and a decrease in flow velocity post-stent deployment was ob-served in 78.9% of cases. Conversely, 21.1% showed increased flow, mainly in aneurysms smaller than 5 mm. No significant association was found between flow changes or MAFA ratio and aneurysm size characteristics. Twenty-two patients (59.5%) underwent re-examination at 6 months, revealing no correlation in MAFA ratio between completely and incompletely occluded aneurysms. Our current investigation, primarily centered on small and medium-sized aneurysms, did not uncover any link between quantitative flow changes assessed using the AneurysmFlow software and the occlusion status of aneurysms at the 6-month follow-up post-flow diverter treatment. Larger case series with extended follow-up imaging are necessary to further explore these findings.

QUANTITATIVE CT ASSESSMENT IN THE CT LUNG CANCER SCREENING POPULATION: A POTENTIAL TOOL FOR SCREENING CANDIDATES FOR BRONCHOSCOPIC LUNG VOLUME REDUCTION

TOPIC: Obstructive Lung Diseases TYPE: Original Investigations PURPOSE: 15 million Americans are estimated to be eligible for CT lung cancer screening (CTLS) based on the U.S. Preventive Services Task Force guidelines. Patients who qualify for CTLS are at high-risk for numerous cardio-pulmonary co-morbidities including emphysema.Lung volume reduction surgery (LVRS) has been shown to provide a mortality benefit in a subset of subjects with upper-lobe emphysema and reduced exercise capacity. Due to the morbidity of the surgical procedure it has not achieved widespread use. Now minimally-invasive forms of LVR (bronchoscopic lung volume reduction, BLVR) with endobronchial valves (EBV) wiht placement of one-way EBVs induces atelectasis of emphysematous areas blocked by the valve and redirects airflow to more normal lung. BLVR has been shown to provide benefit in both upper and lower lobe disease in both heterogenous and homogeneous emphysema, provided there is no collateral ventilation (CV) in the target lobe. Qualifying criteria for BLVR includes FEV1 <45% pred., DLCO > 20% pred., TLC > 100% pred., RV > 175% pred. ( in some cases RV > 150%), (≥200% pred. for homogeneous) and BMI < 35. Fissure integrity of approximately 80% on CT predicts the likelihood of absence of CV and likely clinical benefit of BLVR, although CV should be ruled out through a physiological assessment. CTLS may help identify patients who could clinically benefit from BLVR or LVRS. METHODS: This restrospective, single-center study assessed all baseline CTLS exams performed from January 1, 2012 through September 30, 2017. All patients met the National Comprehensive Cancer Network Guidelines Lung Cancer Screening Version 1.2012 high-risk criteria for lung cancer screening. All analysis was performed utilizing a lung analysis software on IntelliSpace Portal 9.0 (CT COPD, Phillips Healthcare, Cleveland, OH USA). Four research assistants blinded to outcomes data performed the analysis and reviewed the multiplanar images and corrected any errors in interlobar segmentation. Attenuation of each voxel within segmented lungs was calculated automatically. Emphysema destruction was calculated as the sum of voxels with attenuation below -950 Hounsfield units (HU). RESULTS: A total of 4673 patients were included in the study. Quantitative global and lobar emphysema scores were obtained on 4495 patients ( 96.2%). A majority of patients 2845 ( 60.9%) had less than 1% emphysema destruction, 1207 ( 25.8%) had between 1-5%, 235 ( 5.0%) between 5-10% and 208 (4.5%) greater than 10%. In our cohort 124 patients (59.6%) with global % LAA ( low attenuation area) -950> 10% had heterogeneous disease defined as a delta of 15% LAA between ipsilateral lobes. There were 182 patients ( 3.9%) who had at least one lobe with at least 20% lung destruction ( %LAA -950> 20%). CONCLUSIONS: Systematic use of quantitative emphysema CT assessment in a lung cancer screening population was able to identify approximately 4% of the lung screening population who may benefit from further evaluation for candidacy for bronchoscopic or surgical lung volume reduction. Further work is needed to compare and standardize the various commercially available quantitative CT algorithms with low dose CT to better incorporate this information with clinical selection pathways for lung volume reduction. CLINICAL IMPLICATIONS: Quantitative CT Assessment may be a potential screening tool in the lung screening CT population for candidacy of bronchoscopic or surgical lung volume reduction. DISCLOSURES: No relevant relationships by Effie Adjei, source=Web Response Grant funding relationship with Genentech Please note: 9/10/2020 Added 04/23/2021 by Lee Gazourian, source=Web Response, value=Grant/Research Support No relevant relationships by Susan Kim, source=Web Response Consultant relationship with Veracyte Please note: 2019-2021 Added 06/23/2021 by Carla Lamb, source=Web Response, value=Honoraria Speaker/Speaker's Bureau relationship with Covidien Please note: $1001 - $5000 by andrea mckee, source=Web Response, value=Salary Speaker/Speaker's Bureau relationship with Covidien Please note: $1-$1000 by andrea mckee, source=Web Response, value=Travel Advisor relationship with AstraZeneca Please note: 2019-2021 Added 04/22/2021 by Brady McKee, source=Web Response, value=Advisor Fee No relevant relationships by Timothy MD, source=Web Response No relevant relationships by Elizabeth Pagura, source=Web Response No relevant relationships by Julia Rabazzi, source=Web Response No relevant relationships by Shawn Regis, source=Web Responseresearch relationship with Veracyte Please note: 1/1/18-present Added 06/23/2021 by Kimberly Rieger-Christ, source=Web Response, value=Grant/Research Support No relevant relationships by William Thedinger, source=Web Response No relevant relationships by Christoph Wald, source=Web Response, value=Honoraria Removed 04/22/2021 by Christoph Wald, source=Web Response

Molly McCarthy, MBA, BSN, RN, RN-BC

Molly McCarthy, MBA, BSN, RN, RN-BC

Weaning by Surgical Tracheostomy and Portable Ventilators Released ICU Ventilators During Coronavirus Disease 2019 Surge in London

Weaning by Surgical Tracheostomy and Portable Ventilators Released ICU Ventilators During Coronavirus Disease 2019 Surge in London

129-OR: Abnormal Mitochondrial Activity in Pain Processing Regions of the Brain in Painful Diabetic Peripheral Neuropathy

Aims: The management of painful diabetic peripheral neuropathy (pDPN) is inadequate because the disease mechanisms are not fully understood. We assessed cerebral cellular bioenergetics using phosphorus magnetic resonance spectroscopy (31P-MRS) to determine whether high energy phosphate metabolite levels are altered in the pain processing regions of the brain in pDPN. Methods: A total of 66 subjects, 44 with type 2 diabetes (12 no-DPN, 13 painless-DPN and 19 pDPN) and 12 healthy volunteers (HV), underwent detailed clinical and neurophysiological assessments, and 31P-MRS brain imaging at 3-Tesla (Ingenia, Phillips Healthcare) with voxels placed over the right somatosensory cortex and the thalamus (TR 4s, TR 0.26ms, voxel size 21 x 21 x 40mm3). Measures reflecting cellular bioenergetics (mitochondrial function), ATP to phosphocreatine (PCr) and inorganic phosphate (Pi) ratios (ATP:PCr and ATP:Pi) were calculated. Results: There was a significant group effect in the ATP:PCr ratio at the thalamus (p=0.016) and somatosensory cortex (p=0.025). The ATP:PCr at the thalamus was significantly higher in the pDPN group (0.50±0.06) compared to HV (0.44±0.04, p=0.024) and no-DPN (0.42±0.07, p=0.006). Moreover, the ATP:PCr ratio at the somatosensory cortex was significantly higher in pDPN (0.48 ±0.1) compared to HV (0.38 ±0.1, p=0.035). In addition, the ratio correlated with the numeric pain score ratings during the MRI scan at both brain regions. Conclusions: This is the first study to use 31P-MRS to study cerebral energetics in human-DPN and peripheral painful neuropathies. We demonstrated significantly higher ATP:PCr ratios in patients with pDPN in the somatosensory cortex and thalamus, which correlated with pain severity. This is suggestive of increased cellular energy usage in pain processing regions of the brain, perhaps due to continuous nociceptive inputs. Altered cerebral phosphorus metabolite ratios may serve as a biomarker of neuropathic pain in diabetes. Disclosure G.P. Sloan: None. A. Anton: None. D. Selvarajah: None. S. Tesfaye: Advisory Panel; Self; Mitsubishi Tanabe Pharma Corporation, Wörwag Pharma. Speaker’s Bureau; Self; Abbott, AstraZeneca, Grunenthal Group, Napp Pharmaceuticals, Novo Nordisk Inc., Pfizer Inc. I.D. Wilkinson: None.

533-P: Predicting Treatment Response in Painful Diabetic Neuropathy Using Magnetic Resonance Brain Imaging

Background: Painful diabetic polyneuropathy (DPN) is difficult to manage as treatment response is often varied. The aim of this study was to explore the central mechanisms to explain the variance in treatment response. Methods: Forty-five consecutive patients who received intravenous lidocaine treatment for painful DPN were screened. All subjects completed a treatment efficacy questionnaire. Twenty-nine patients (responders n=14 and non-responders n=15) along with 26 healthy controls subsequently underwent multimodal brain magnetic resonance (MR) imaging to acquire anatomical and resting state functional data (3T, Achieva, Phillips Healthcare). Results: There was no significant difference in age (p=0.53), pain duration (p=0.89), diabetes duration (p=0.19) and clinical parameters of neuropathy (TCNS, p=0.16 and NTSS-6, p=0.61) between responders and non-responders to lidocaine treatment. Neither was there a difference in the use of concurrent neuropathic pain treatments. Non-responders to lidocaine had significantly lower mean S1 cortical volumes and mean number of vertices compared to responders and healthy controls (ANOVA p=0.02 and 0.02 respectively). There was no significant difference in S1 cortical volumes or vertices between responders and healthy controls. There was significantly greater resting state functional connectivity in lidocaine responders between the insula cortex [F(4)(13)=10.33; p-FDR=0.01] and the orbital frontal cortex [T(20)=3.88; p-FDR=0.02], amygdala [T(20)=3.65; p-FDR=0.02] and anterior cingulate gyrus [T(20)=4.04; p-FDR=0.01]. Conclusion: To the best of our knowledge, this is the first assessment of CNS mechanisms of treatment response in painful DPN. Key nociceptive processing areas showed decreased grey matter density (S1 cortex) and reduced functional connectivity (insula) relating to treatment response. MR neuroimaging may serve as a Central Pain Signature which could be used to predict treatment response. Disclosure K. Teh: None. I.D. Wilkinson: None. G.P. Sloan: None. S. Tesfaye: Advisory Panel; Self; Mitsubishi Tanabe Pharma Corporation, Wörwag Pharma. Speaker’s Bureau; Self; Abbott, AstraZeneca, Grunenthal Group, Napp Pharmaceuticals, Novo Nordisk Inc., Pfizer Inc. D. Selvarajah: None. Funding European Foundation for the Study of Diabetes; University of Sheffield

The Lorne Pier to Pub.

Lorne Lifesaving Club, Lorne, Victoria, Australia Phillips Healthcare supplies the monitoring equipment for the Pier to Pub event. Epworth Healthcare supplies drugs and intravenous equipment for the event. Both provide free of charge but they do get the right to advertise this at the event. The author is an honorary life member of Lorne Surf Lifesaving Club. Address Correspondence to: Kevin Moriarty, OAM, MBBS, FANZCA, 3/655 Victoria St., Abbotsford, Vic. 3067, Australia. E-mail: [email protected]

0331 ACTIGRAPHY IN INSOMNIA WITH AND WITHOUT EVENT-MARKING

Use of actigraphy (ACT) in insomnia to objectively document sleep remains problematic primarily due to its insensitivity for wakefulness. One approach to enhancing validity is use of participant event marking to document time-in-bed (TIB). We sought to determine whether event marking TIB enhances ACT validity to PSG compared to soft-ware determined TIB. Persons (N=16), aged 23–61 yrs, meeting DSM-V criteria for insomnia and a PSG sleep efficiency of ≤85%, no other sleep, psychiatric or drug dependency disorders and in good health were recruited. Following a screening 8-hr nocturnal PSG participants returned home with Actiwatchs (Spectrum Plus, Phillips Healthcare, Bend OR) to be worn nightly for 7 consecutive nights. Instructions were to spend 7–9 hrs in bed and to press event markers when trying to sleep and arising in the morning. ACT data were analyzed using the Phillips Actiware 6 software. The sleep parameters derived from the software (AUTO) determined TIB were compared to those of the event-marked (MARK) TIB for validation to PSG. The sleep parameters compared were total sleep time (TST), sleep efficiency (SE), sleep latency (LAT), wake after sleep onset (WASO), and number of awakenings (NWAK). TIB was not marked in 10% of the total 112 nights and means over the first 3 nights were used for comparisons. While MARK data correlated significantly (p<.05) to PSG on TST(r=.61), SE (r=.83), and LAT (r=.58), no AUTO generated parameters did. The correlation coefficient for PSG to AUTO vs MARK SE was significantly smaller (t=2.46, p<.05). Relative to MARK, AUTO overestimated TST (t=2.61, p<.02) and showed a trend (p<.10) for underestimating WASO and NWAK. In insomnia ACT validity to PSG is enhanced by requiring that participants use an event marker to indicate TIB and data loss due to failure to use the event marker is relatively low (10%). NIDA, grant#: R01DA038177 awarded to Dr. Roehrs.

The Evaluation of a Noninvasive Respiratory Volume Monitor in Pediatric Patients Undergoing General Anesthesia

Pediatric patients following surgery are at risk for respiratory compromise such as hypoventilation and hypoxemia depending on their age, comorbidities, and type of surgery. Quantitative measurement of ventilation in nonintubated infants/children is a difficult and inexact undertaking. Current respiratory assessment in nonintubated patients relies on oximetry data, respiratory rate (RR) monitors, and subjective clinical assessment, but there is no objective measure of respiratory parameters that could be utilized to predict early respiratory compromise. New advances in technology and digital signal processing have led to the development of an impedance-based respiratory volume monitor (RVM, ExSpiron, Respiratory Motion, Inc, Waltham, MA). The RVM has been shown to provide accurate real-time, continuous, noninvasive measurements of tidal volume (TV), minute ventilation (MV), and RR in adult patients.In this prospective observational study, our primary aim was to determine whether the RVM accurately measures TV, RR, and MV in pediatric patients. A total of 72 pediatric patients (27 females, 45 males), ASA I to III, undergoing general anesthesia with endotracheal intubation were enrolled. After endotracheal intubation, continuous data of MV, TV, and RR were recorded from the RVM and an in-line monitoring spirometer (NM3 monitor, Phillips Healthcare). RVM and NM3 measurements of MV, TV, and RR were compared during a 10-minute period prior to the incision ("Presurgery") and a 10-minute period after the end of surgery ("Postsurgery"). Relative errors were calculated over 1-minute segment within each 10-minute period. Bias, precision, and accuracy were calculated using Bland-Altman analyses and paired-difference equivalence tests were performed. Combined across the Presurgery and Postsurgery periods, the RVM's mean measurement bias (RVM - NM3 measurement) for MV was -3.8% (95% limits of agreement) (±1.96 SD): (-19.9% to 12.2%), for TV it was -4.9 (-21.0% to 11.3%), and for RR it was 1.1% (-4.1% to 6.2%). The mean measurement accuracies for MV, TV, and RR were 11.9%, 12.0%, and 4.2% (0.6 breaths/min), respectively. Note that lower accuracy numbers correspond to more accurate RVM measurements. The equivalence tests rejected the null hypothesis that the RVM and NM3 have different mean values and conclude with 90% power that the measurements of MV, TV, and RR from the RVM and NM3 are equivalent within ±10%. Our data indicate acceptable agreement between RVM and NM3 measurements in pediatric mechanically-ventilated patients. Future studies assessing the capability of the RVM to detect respiratory compromise in other clinical settings are needed.

Spleen Stiffness in Myeloproliferative Disease Related Splanchnic Vein Thrombosis

Introduction: Myeloproliferative neoplasms (MPN) account for the majority of non-cirrhotic and non-malignant Splanchnic vein thrombosis (SVT). SVT comprises extrahepatic portal vein obstruction (EHPVO), Budd-Chiari syndrome (BCS), mesenteric vein thrombosis (MVT) and splenic vein thrombosis (SpVT). 30% of EHPVO and 45% BCS are attributable to MPN. Portal hypertension (PH) is a major complication of SVT and hepatic and splenic elastography is increasingly used as a non-invasive tool for the characterization of hepatic fibrosis and PH. We had already established in 17 patients with chronic liver disease (CLD) that SS was the only predictor of clinically significant PH (CSPH) with an AUROC of 0.908, SE=0.45, p<0.0001, 95% CI 0.821-0.996, Cut-off 44.3 kPa, sensitivity 88%, specificity 85%. We wished to explore the role of tissue stiffness in characterizing splenomegaly in MPN patients with SVT.Methods: As part of an observational study of patients with MPN-SVT (Mascot study) from September 2015 we assessed 18 patients with MPN-SVT for spleen stiffness (SS) and spleen size (SSz) using point shear wave elastography (ElastoPQ Phillips Healthcare system). 14 patients had measurements at two time points 3-8 months apart (median 4.5m). Their clinical and radiologic details are presented in Table 1. SVT was diagnosed 1-16 years prior to the investigations (median 5 years). Patients were treated with LMWH and warfarin. Most patients also received Aspirin at the outset and 2/14 patients had thrombolysis in the acute phase. Review of SVT with imaging by CT/MR was undertaken at 6-12 monthly intervals. MPN was diagnosed on the basis of blood and bone marrow morphology and molecular analysis. 1 patient had CALR mutation, the others JAK2V617F mutation. Treatment included venesection, Hydroxycarbamide, Pegylated Interferon and Ruxolitinib.Results: 8/14 were male, median age 45 years. All patients had splenomegaly at baseline. All patients showed stable or improved appearances of the site of thrombus with patent TIPS on follow-up imaging.9/14 were on MPN directed medication; median time between commencing medication and 1st SS measurement was 3 months (range -3m to 7 yrs) including 1 patient who commenced Ruxolitinib 3 months after 1st assessment but 7 months before the 2nd assessment (patient 12).In 6/14 patients SS worsened (pts 1-6, Table 1), SSz was stable or worse. 4/6 had TIPS and 4/6 had cytoreductive treatment including 2 receiving Ruxolitinib.In 6 patients SS reduced along with a reduction in SSz (pts 9-14). 2 had TIPS and 5/6 had cytoreductive treatment including 4 receiving Ruxolitinib.Patients with increasing SS over time also had microcytic erythrocytosis that persisted over the period of measurement. Patients with improving SS had improvement in the MCV leading to normal values of RBC and MCV (Fig 1).Conclusions:In this small pilot study on a cohort of well characterised MPN-SVT patients we have assessed SS and considered clinical variables affecting this. This study shows that1. Spleen elastography provides a novel method of characterising the spleen. In patients with CLD it correlates well with clinically significant PH.2. All patients with MPN-SVT have residual splenomegaly3. Patients had no recurrence of the SVT after adequate anticoagulation was instituted.4. More patients with reduction in SS received JAK2 inhibitor drugs.5. Reduction in SS is not a consistent feature of PH reduction via TIPS.6. Persistent microcytic erythrocytosis is seen in the patients with worsening spleen stiffness and improvement in patients with improving stiffness.7. The dynamics of splenomegaly in these patients remains unclear.Discussion: TIPS reduces portal pressure and in PH related to CLD and thereby reduces SSz. In our patients this has not been a consistent result. Previous studies have shown a reduction in SSz with Ruxolitinib. In our patients the reduction is size and stiffness is noted in patients on Ruxolitinib/Pegylated Interferon but it is not consistent. This lack of response in some patients occurs despite normalisation /improvement of counts. The persistence of splenomegaly with abnormal stiffness in the face of TIPS and cytoreduction is puzzling and worthy of longitudinal studies using elastography which may offer valuable insights into the role and behaviour of the spleen in these disorders. [Display omitted] [Display omitted] DisclosuresSekhar:Novartis: Research Funding.

TU‐H‐CAMPUS‐JeP2‐02: Interobserver Variability of CT, PET‐CT and MRI Based Primary Tumor Delineation for Lung Cancer

Purpose:Target delineation in lung cancer radiotherapy has, in general, large variability. MRI has so far not been investigated in detail for lung cancer delineation variability. The purpose of this study is to investigate delineation variability for lung tumors using MRI and compare it to CT alone and PET‐CT based delineations.Methods:Seven physicians delineated the primary tumor volumes of nine patients for the following scenarios: (1) CT only; (2) post‐contrast T1‐weighted MRI registered with diffusion‐weighted MRI; and (3) PET‐CT fusion images. To compute interobserver variability, the median surface was generated from all observers’ contours and used as the reference surface. A single physician labeled the interface types (tumor to lung, atelectasis (collapsed lung), hilum, mediastinum, or chest‐wall) on the median surface. Volume variation (normalized to PET‐CT volume), minimum distance (MD), and bidirectional local distance (BLD) between individual observers’ contours and the reference contour were measured.Results:CT‐ and MRI‐based normalized volumes were 1.61±0.76 (mean±SD) and 1.38±0.44, respectively, both significantly larger than PET‐CT (p&lt;0.05, paired t‐test). The overall uncertainty (root mean square of SD values over all points) of both BLD and MD measures of the observers for the interfaces were not significantly different (p&gt;0.05, two‐samples t‐test) for all imaging modalities except between tumor‐mediastinum and tumor‐atelectasis in PET‐CT. The largest mean overall uncertainty was observed for tumor‐atelectasis interface, the smallest for tumor‐mediastinum and tumor‐lung interfaces for all modalities. The whole tumor uncertainties for both BLD and MD were not significantly different between any two modalities (p&gt;0.05, paired t‐test). Overall uncertainties for the interfaces using BLD were similar to using MD.Conclusion:Large volume variations were observed between the three imaging modalities. Contouring variability appeared to depend on the interface type. This study will be useful for understanding the delineation uncertainty for radiotherapy planning of lung cancer using different imaging modalities.Disclosures: Research agreement with Phillips Healthcare (GH and EW), National Institutes of Health Licensing agreement with Varian Medical Systems (GH and EW), research grants from the National Institute of Health (GH and EW), UpToDate royalties (EW), and none (others). Authors have no potential conflicts of interest to disclose.

TU-FG-202-02: Modern Intracavitary GYN Brachytherapy

The greater use of magnetic resonance imaging (MR) in brachytherapy, for both image based planning and image guided procedures, presents a number of challenges for the physicist involved. MR is widely acknowledged as the imaging modality of choice to appreciate a patient's pelvic anatomy and is thus used more often for brachytherapy of gynecologic and prostate cancers. Incorporating MR in brachytherapy treatments requires changes throughout the clinical workflow from implantation through target definition, applicator digitization and post-implant evaluation. These presentations will review the some of the concerns encountered in image based brachytherapy environment, highlight the challenges to incorporating more information from MR, and discuss some of the technical developments underway to facilitate the further use of MR in brachytherapy. Learning Objectives: 1.To review the rationale for incorporating MR in image based brachytherapy for treatment of gynecologic and prostate cancers. 2.To review the technical challenges encountered when using brachytherapy devices in an MR environment. 3.To discuss some developments to facilitate MR based planning and guidance. J. Cunha, Phillips Healthcare

TU-FG-202-00: Advances and Innovations in Image Guided Brachytherapy

The greater use of magnetic resonance imaging (MR) in brachytherapy, for both image based planning and image guided procedures, presents a number of challenges for the physicist involved. MR is widely acknowledged as the imaging modality of choice to appreciate a patient's pelvic anatomy and is thus used more often for brachytherapy of gynecologic and prostate cancers. Incorporating MR in brachytherapy treatments requires changes throughout the clinical workflow from implantation through target definition, applicator digitization and post-implant evaluation. These presentations will review the some of the concerns encountered in image based brachytherapy environment, highlight the challenges to incorporating more information from MR, and discuss some of the technical developments underway to facilitate the further use of MR in brachytherapy. Learning Objectives: 1.To review the rationale for incorporating MR in image based brachytherapy for treatment of gynecologic and prostate cancers. 2.To review the technical challenges encountered when using brachytherapy devices in an MR environment. 3.To discuss some developments to facilitate MR based planning and guidance. J. Cunha, Phillips Healthcare

TU-FG-202-03: Recent Technology Innovations in Prostate Brachytherapy

The greater use of magnetic resonance imaging (MR) in brachytherapy, for both image based planning and image guided procedures, presents a number of challenges for the physicist involved. MR is widely acknowledged as the imaging modality of choice to appreciate a patient's pelvic anatomy and is thus used more often for brachytherapy of gynecologic and prostate cancers. Incorporating MR in brachytherapy treatments requires changes throughout the clinical workflow from implantation through target definition, applicator digitization and post-implant evaluation. These presentations will review the some of the concerns encountered in image based brachytherapy environment, highlight the challenges to incorporating more information from MR, and discuss some of the technical developments underway to facilitate the further use of MR in brachytherapy. Learning Objectives: 1. To review the rationale for incorporating MR in image based brachytherapy for treatment of gynecologic and prostate cancers. 2. To review the technical challenges encountered when using brachytherapy devices in an MR environment. 3. To discuss some developments to facilitate MR based planning and guidance. J. Cunha, Phillips Healthcare

TU-FG-202-01: Modern Intracavitary GYN Brachytherapy

The greater use of magnetic resonance imaging (MR) in brachytherapy, for both image based planning and image guided procedures, presents a number of challenges for the physicist involved. MR is widely acknowledged as the imaging modality of choice to appreciate a patient's pelvic anatomy and is thus used more often for brachytherapy of gynecologic and prostate cancers. Incorporating MR in brachytherapy treatments requires changes throughout the clinical workflow from implantation through target definition, applicator digitization and post-implant evaluation. These presentations will review the some of the concerns encountered in image based brachytherapy environment, highlight the challenges to incorporating more information from MR, and discuss some of the technical developments underway to facilitate the further use of MR in brachytherapy. Learning Objectives: 1. To review the rationale for incorporating MR in image based brachytherapy for treatment of gynecologic and prostate cancers. 2. To review the technical challenges encountered when using brachytherapy devices in an MR environment. 3. To discuss some developments to facilitate MR based planning and guidance. J. Cunha, Phillips Healthcare

Pediatric perioperative adverse events requiring rapid response: a retrospective case-control study.

Perioperative pediatric adverse events have been challenging to study within and across institutions due to varying definitions, low event rates, and incomplete capture. The aim of this study was to determine perioperative adverse event prevalence and to evaluate associated case characteristics and potential contributing factors at an academic pediatric quaternary-care center. At the Children's Hospital of Philadelphia (CHOP), perioperative adverse events requiring rapid response assistance are termed Anesthesia Now (AN!) events. They have been accurately captured and entered into a quality improvement database since 2010. Adverse events involving open heart and cardiac catheterization cases are managed separately and not included in this database. We conducted a retrospective case-control study utilizing Compurecord (Phillips Healthcare, Andover, MA, USA), EPIC (EPIC, Verona, WI, USA), and Chartmaxx (MedPlus, Mason, OH, USA) systems matching AN! event cases to noncardiac controls (1 : 2) based on surgical date. From April 16, 2010 to September 25, 2012, we documented 213 AN! events in the noncardiac perioperative complex and remote sites at our main hospital. AN! prevalence was 0.0043 (1 : 234) with a 95% confidence interval (CI) (0.0037, 0.0049). Respiratory events, primarily laryngospasm, were most common followed by events of cardiovascular etiology. Median age was lower in the AN! group than in controls, 2.86 years (interquartile range 0.94, 10.1) vs 6.20 (2.85, 13.1), P < 0.0001. Odds ratios (with 95% CI) for age, 0.969 (0.941, 0.997); American Society of Anesthesiologists physical status, 1.67 (1.32, 2.12); multiple (≥2) services, 2.27 (1.13, 4.55); nonoperating room vs operating room location, 0.240 (0.133, 0.431); and attending anesthesiologist's experience, 0.976 (0.959, 0.992) were all significant. Decreased age, increased comorbidities, multiple (vs single) surgical services, operating room (vs nonoperating room) location, and decreased staff experience were associated with increased risk of AN! events, which were predominantly respiratory in origin.

11 Left ventricular end diastolic filling pressure predicted by left atrial strain measured by feature tracking

Introduction Left ventricular end-diastolic filling pressure (LVEDP) is an invasive measure of LV function obtained at cardiac catheterisation (CC) that predicts prognosis and guides therapeutic strategy. Echocardiographic E/E’ ratio has been shown to be inaccurate for estimation of LVEDP. Feature-tracking cardiovascular magnetic resonance (FT-CMR) is a novel method for quantification of myocardial deformation and can be used to quantitatively assess left atrial (LA) function. Currently there is no validated MRI parameter that estimates LVEDP. We hypothesised that LA strain correlates to LVEDP. Methods 14 patients in sinus rhythm, with severe AS underwent a 1.5T CMR protocol (Ingenia, Phillips Healthcare, Best, The Netherlands). LVEDP was recorded at the time of CC by standard techniques. 4 chamber and mid ventricular short axis steady state free procession cine images were obtained: LA endocardial and epicardial borders were traced manually on the end-diastolic slice and strain measurements were calculated using commercially available post-processing software (CVI42, Circle Cardiovascular Imaging, Calgary, Alberta, Canada). Results Patients were divided into 2 groups: low EDP (13 ± 2.4mmHg) and high EDP (36.1 ± 3.4mmHg) (p Conclusion LA function (PALS) as measured by FT-CMR is independently associated with LVEDP and may have a role in predicting LV filling pressures via a routine CMR protocol.

In vitro and in vivo magnetic resonance imaging with chlorotoxin-conjugated superparamagnetic nanoprobes for targeting hepatocarcinoma.

The present study aimed to assess the in vitro and in vivo magnetic resonance imaging (MRI) features of chlorotoxin (CTX)-conjugated superparamagnetic iron oxide (SPIO) nanoprobes. CTX-conjugated nanoprobes were composed of SPIO coated with polyethylene glycol (PEG) and conjugated with CTX. The nanoprobes were termed SPIO-PEG-CTX. MRI of the SPIO and SPIO-PEG-CTX solutions at a different concentration was performed with a 3.0-T MRI scanner (Philips Achieva 3.0T X Series; Phillips Healthcare, The Netherlands). Rabbit VX2 hepatocarcinoma was established by a traditional laparotomy method (injection of the tumor particles into the liver using a 15G syringe needle) following approval by the institutional animal care and use committee. Contrast-enhanced MRI of VX2 rabbits (n=8) was performed using the same MRI scanner with SPIO‑PEG-CTX solutions as the contrast agent. Data were analyzed with calibration curve and a paired t-test. The SPIO-PEG-CTX nanoparticles were successfully prepared. With increasing concentrations of the solutions, the MRI signal intensity was increased at T1WI, but decreased at T2WI, which were the same as that for SPIO. Rabbit VX2 carcinoma appeared as a low MRI signal at T1WI, and high at T2WI. After injection of the contrast agent, the MRI signal of carcinoma was decreased relative to that before injection at T2WI (1,161±331.5 vs. 1,346±300.5; P=0.004<0.05), while the signal of the adjacent normal hepatic tissues was unchanged (480.6±165.1 vs. 563.4±67.8; P=0.202>0.05). The SPIO-PEG-CTX nanoparticles showed MRI negative enhancement at T2WI and a targeting effect in liver cancer, which provides the theoretical basis for further study of the early diagnosis of hepatocellular carcinoma.

MO‐B‐BRD‐01: Creation of 3D Printed Phantoms for Clinical Radiation Therapy

This session is designed so that the learning objectives are practical. The intent is that the attendee may take home an understanding of not just the technology, but also the logistical steps necessary to execute these 3D printing techniques in the clinic. Four practical 3D printing topics will be discussed: (i) Creating bolus and compensators for photon machines; (ii) tools for proton therapy; (iii) clinical applications in imaging; (iv) custom phantom design for clinic and research use. The use of 3D printers within the radiation oncology setting is proving to be a useful tool for creating patient specific bolus and compensators with the added benefit of cost savings. Creating the proper protocol is essential to ensuring that the desired effect is achieved and modeled in the treatment planning system. The critical choice of printer material (since it determines the interaction with the radiation) will be discussed. Selection of 3D printer type, design methods, verification of dose calculation, and the printing process will be detailed to give the basis for establishing your own protocol for electron and photon fields. A practical discussion of likely obstacles that may be encountered will be included. The diversity of systems and techniques in proton facilities leads to different facilities having very different requirements for beam modifying hardware and quality assurance devices. Many departments find the need to design and fabricate facility‐specific equipment, making 3D printing an attractive technology. 3D printer applications in proton therapy will be discussed, including beam filters and compensators, and the design of proton therapy specific quality assurance tools. Quality control specific to 3D printing in proton therapy will be addressed. Advantages and disadvantages of different printing technology for these applications will also be discussed. 3D printing applications using high‐resolution radiology‐based imaging data will be presented. This data is used to 3D print individualized physical models of patient's unique anatomy for aid in planning complex and challenging surgical procedures. Methods, techniques and imaging requirements for 3D printing anatomic models from imaging data will be discussed. Specific applications currently being used in the radiology clinic will be detailed. Standardized phantoms for radiation therapy are abundant. However, custom phantom designs can be advantageous for both clinical tasks and research. 3D printing is a useful method of custom fabrication that allows one to construct custom objects relatively quickly. Possibilities for custom radiotherapy phantoms range from 3D printing a hollow shell and filling the shell with tissue equivalent materials to fully printing the entire phantom with materials that are tissue equivalent as well as suitable for 3D printing. A range of materials available for use in radiotherapy phantoms and in the case of phantoms for dosimetric measurements, this choice is critical. The necessary steps required will be discussed including: modalities of 3D model generation, 3D model requirements for 3D printing, generation of machine instructions from the 3D model, and 3D printing techniques, choice of phantoms material, and troubleshooting techniques for each step in the process. Case examples of 3D printed phantoms will be shown. Learning Objectives: Understand the types of 3D modeling software required to design your device, the file formats required for data transfer from design software to 3D printer, and general troubleshooting techniques for each step of the process. Learn the differences between materials and design for photons vs. electrons vs. protons. Understand the importance of material choice and design geometries for your custom phantoms. Learn specific steps of quality assurance and quality control for 3D printed beam filters and compensators for proton therapy. Learn of special 3D printing applications for imaging. Cunha: Research support from Phillips Healthcare.

MO‐B‐BRD‐00: Clinical Applications of 3D Printing

This session is designed so that the learning objectives are practical. The intent is that the attendee may take home an understanding of not just the technology, but also the logistical steps necessary to execute these 3D printing techniques in the clinic. Four practical 3D printing topics will be discussed: (i) Creating bolus and compensators for photon machines; (ii) tools for proton therapy; (iii) clinical applications in imaging; (iv) custom phantom design for clinic and research use. The use of 3D printers within the radiation oncology setting is proving to be a useful tool for creating patient specific bolus and compensators with the added benefit of cost savings. Creating the proper protocol is essential to ensuring that the desired effect is achieved and modeled in the treatment planning system. The critical choice of printer material (since it determines the interaction with the radiation) will be discussed. Selection of 3D printer type, design methods, verification of dose calculation, and the printing process will be detailed to give the basis for establishing your own protocol for electron and photon fields. A practical discussion of likely obstacles that may be encountered will be included. The diversity of systems and techniques in proton facilities leads to different facilities having very different requirements for beam modifying hardware and quality assurance devices. Many departments find the need to design and fabricate facility‐specific equipment, making 3D printing an attractive technology. 3D printer applications in proton therapy will be discussed, including beam filters and compensators, and the design of proton therapy specific quality assurance tools. Quality control specific to 3D printing in proton therapy will be addressed. Advantages and disadvantages of different printing technology for these applications will also be discussed. 3D printing applications using high‐resolution radiology‐based imaging data will be presented. This data is used to 3D print individualized physical models of patient's unique anatomy for aid in planning complex and challenging surgical procedures. Methods, techniques and imaging requirements for 3D printing anatomic models from imaging data will be discussed. Specific applications currently being used in the radiology clinic will be detailed. Standardized phantoms for radiation therapy are abundant. However, custom phantom designs can be advantageous for both clinical tasks and research. 3D printing is a useful method of custom fabrication that allows one to construct custom objects relatively quickly. Possibilities for custom radiotherapy phantoms range from 3D printing a hollow shell and filling the shell with tissue equivalent materials to fully printing the entire phantom with materials that are tissue equivalent as well as suitable for 3D printing. A range of materials available for use in radiotherapy phantoms and in the case of phantoms for dosimetric measurements, this choice is critical. The necessary steps required will be discussed including: modalities of 3D model generation, 3D model requirements for 3D printing, generation of machine instructions from the 3D model, and 3D printing techniques, choice of phantoms material, and troubleshooting techniques for each step in the process. Case examples of 3D printed phantoms will be shown. Learning Objectives: Understand the types of 3D modeling software required to design your device, the file formats required for data transfer from design software to 3D printer, and general troubleshooting techniques for each step of the process. Learn the differences between materials and design for photons vs. electrons vs. protons. Understand the importance of material choice and design geometries for your custom phantoms. Learn specific steps of quality assurance and quality control for 3D printed beam filters and compensators for proton therapy. Learn of special 3D printing applications for imaging. Cunha: Research support from Phillips Healthcare.