Federated Learning Survival Model and Potential Radiotherapy Decision Support Impact Assessment for Non-small Cell Lung Cancer Using Real-World Data

AIMS

The objective of this study was to develop a two-year overall survival model for inoperable stage I-III non-small cell lung cancer (NSCLC) patients using routine radiation oncology data over a federated (distributed) learning network and evaluate the potential of decision support for curative versus palliative radiotherapy.

METHODS

A federated infrastructure of data extraction, de-identification, standardisation, image analysis, and modelling was installed for seven clinics to obtain clinical and imaging features and survival information for patients treated in 2011-2019. A logistic regression model was trained for the 2011-2016 curative patient cohort and validated for the 2017-2019 cohort. Features were selected with univariate and model-based analysis and optimised using bootstrapping. System performance was assessed by the receiver operating characteristic (ROC) and corresponding area under curve (AUC), C-index, calibration metrics and Kaplan-Meier survival curves, with risk groups defined by model probability quartiles. Decision support was evaluated using a case-control analysis using propensity matching between treatment groups.

RESULTS

1655 patient datasets were included. The overall model AUC was 0.68. Fifty-eight percent of patients treated with palliative radiotherapy had a low-to-moderate risk prediction according to the model, with survival times not significantly different (p = 0.87 and 0.061) from patients treated with curative radiotherapy classified as high-risk by the model. When survival was simulated by risk group and model-indicated treatment, there was an estimated 11% increase in survival rate at two years (p < 0.01).

CONCLUSION

Federated learning over multiple institution data can be used to develop and validate decision support systems for lung cancer while quantifying the potential impact of their use in practice. This paves the way for personalised medicine, where decisions can be based more closely on individual patient details from routine care.

The Platysma Contraction Pattern in Healthy Adults: A Vector Analysis Study

BACKGROUND

The platysma muscle's role in lower face dynamics is complex. Multiple insertion points to soft-tissue structures at various levels in the lower face create a multifaceted contraction pattern. To avoid adverse effects in cosmetic procedures when targeting the platysma, its anatomy and physiology must be understood. Clinical observations hint at a bidirectional contraction pattern.

METHODS

Eighteen healthy volunteers (13 women and five men) with a mean age of 44.2 ± 10.1 years were enrolled. Skin displacement vector analysis was used on maximal platysma contraction to characterize and calculate the movement of the neck and lower face skin.

RESULTS

In all of the participants, a bidirectional movement of the skin was observed: the skin of the lower face and inferior to the jawline moved caudally, whereas the skin of the lower neck moved cephalad. Both movements converged at a line situated at 54% ± 10% and 55% ± 8% of the length between the clavicle and the inferior base of the ear lobe in men and women, respectively ( P = 0.70).

CONCLUSIONS

The platysma is a bidirectional muscle with a line of convergence. Whereas the superior portion acts as lip depressor, the lower portion elevates the skin of the upper chest and lower neck. This transition can explain some of the clinically observed adverse effects of neuromodulation of the neck area. It can potentially direct neuromodulation injections to focus above the convergence line to better address lower face descent.

Improving plan quality in cervical brachytherapy using a simple knowledge-based prediction tool for OAR dose (D2cm3)

PURPOSE

Toxicity from cervical brachytherapy has been demonstrated to correlate with the D2cm3 of the bladder, rectum, and bowel. This suggests a simplified version of knowledge-based planning investigating the relationship of the overlap distance for 2cm3 and the D2cm3 from planning may be possible. This work demonstrates the feasibility of simple knowledge-based planning to predict the D2cm3, detect suboptimal plans, and improve plan quality.

METHODS AND MATERIALS

The overlap volume histogram (OVH) method was used to determine the distance for 2cm3 of overlap between the OAR and CTV_HR. Linear plots modeled the OAR D2cm3 and 2cm3 overlap distance. Two datasets of 20 patients (plans from 43 insertions in each dataset) were used to create two independent models, and the performance of each model was compared using cross-validation. Doses were scaled to ensure consistent CTV_HR D90 values. The predicted D2cm3 is entered as the maximum constraint in the inverse planning algorithm.

RESULTS

Mean bladder D2cm3 decreased by 2.9% for the models from each dataset, mean rectal D2cm3 decreased 14.9% for the model from dataset 1 and 6.0% for the model from dataset 2, mean sigmoid D2cm3 decreased 10.7% for the model from dataset 1 and 6.1% for the model from dataset 2, mean bowel D2cm3 decreased 4.1% for the model from dataset 1 but no statistically significant difference was observed for the model from dataset 2.

CONCLUSIONS

A simplified knowledge-based planning method was used to predict D2cm3 and was able to automate optimization of brachytherapy plans for locally advanced cervical cancer.

Credit for Truly Novel Ideas? A Critical Approach to the Intellectual Authorship in Surgery

The formation of new ideas and techniques in medicine and surgery is crucial to bettering the medical field and the quality of medical care. The transmission of these new ideas is a source of pride and recognition for physicians who devote their lives to patient care. The quality and integrity of the medical literature that results from seminal medical ideas are an essential but unregulated field. From time to time, there are discussions in the medical literature about the authorship of an idea/strategy/technique. In this digital era, where communication works at an unmeasurable speed, the authenticity of medical communication requires honesty and verification. The possibility of unreliable or false information exists, and the need to verify "new" information as accurate and honest is crucial. Rhythm, genuine, and fake (fair/unfair) information circulates at high speed, and suddenly everything one encounters is represented as "true and often represented as new." Regarding medical science and particularly surgery - we are overloaded daily with new techniques, new names, new strategies, and everything. Several questions regarding the authenticity of any publication or scientific communication exist. A critical approach is done in this article.

A kinematics-based method for creating deformed patient-derived head and neck CT scans. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2023;2023:1-4. [PMID: 38083025 DOI: 10.1109/embc40787.2023.10340930] [Citation(s) in RCA: 0] [Impact Index Per Article: 0]

CT scans of the head and neck have multiple clinical uses, and simulating deformation of these CT scans allows for predicting patient motion and data augmentation for machine-learning methods. Current methods for creating patient-derived deformed CT scans require multiple scans or use unrealistic head and neck motion. This paper describes the CTHeadDeformation software package which allows for realistic synthetic deformation of head and neck CT scans for small amounts of motion. CTHeadDeformation is a python-based package that uses a kinematics-based approach using anatomical landmarks, and rigid/non-rigid registration to create a realistic patient-derived deformed CT scan. CTHeadDeformation is also designed for simple clinical implementation. The CTHeadDeformation software package was demonstrated on a head and neck CT scan of one patient. The CT scan was deformed in the anterior-posterior, superior-inferior, and left-right directions. Internal organ motion and more complex combination motions were also simulated. The results showed the patient's CT scan was able to be deformed in a way that preserved the shape and location of the anatomy.Clinical Relevance- This method allows for the realistic simulation of head and neck motion in CT scans. Clinical applications including simulating how patient motion affects radiation therapy treatment effectiveness. The CTHeadDeformation software can also be used to train machine-learning networks that are robust to patient motion, or to generate ground truth images for imaging or segmentation grand challenges.

Realistic CT data augmentation for accurate deep-learning based segmentation of head and neck tumors in kV images acquired during radiation therapy

BACKGROUND

Using radiation therapy (RT) to treat head and neck (H&N) cancers requires precise targeting of the tumor to avoid damaging the surrounding healthy organs. Immobilisation masks and planning target volume margins are used to attempt to mitigate patient motion during treatment, however patient motion can still occur. Patient motion during RT can lead to decreased treatment effectiveness and a higher chance of treatment related side effects. Tracking tumor motion would enable motion compensation during RT, leading to more accurate dose delivery.

PURPOSE

The purpose of this paper is to develop a method to detect and segment the tumor in kV images acquired during RT. Unlike previous tumor segmentation methods for kV images, in this paper a process for generating realistic and synthetic CT deformations was developed to augment the training data, and make the segmentation method robust to patient motion. Detecting the tumor in 2D kV images is a necessary step towards 3D tracking of the tumor position during treatment.

METHOD

In this paper a conditional generative adversarial network (cGAN) is presented that can detect and segment the gross tumor volume (GTV) in kV images acquired during H&N RT. Retrospective data from 15 H&N cancer patients obtained from the Cancer Imaging Archive were used to train and test patient-specific cGANs. The training data consisted of digitally reconstructed radiographs (DRRs) generated from each patient's planning CT and contoured GTV. Training data was augmented by using synthetically deformed CTs to generate additional DRRs (in total 39600 DRRs per patient or 25200 DRRs for nasopharyngeal patients) containing realistic patient motion. The method for deforming the CTs was a novel deformation method based on simulating head rotation and internal tumor motion. The testing dataset consisted of 1080 DRRs for each patient, obtained by deforming the planning CT and GTV at different magnitudes to the training data. The accuracy of the generated segmentations was evaluated by measuring the segmentation centroid error, Dice similarity coefficient (DSC) and mean surface distance (MSD). This paper evaluated the hypothesis that when patient motion occurs, using a cGAN to segment the GTV would create a more accurate segmentation than no-tracking segmentations from the original contoured GTV, the current standard-of-care. This hypothesis was tested using the 1-tailed Mann-Whitney U-test.

RESULTS

The magnitude of our cGAN segmentation centroid error was (mean ± standard deviation) 1.1 ± 0.8 millimeters and the DSC and MSD values were 0.90 ± 0.03 and 1.6 ± 0.5 millimeters respectively. Our cGAN segmentation method reduced the segmentation centroid error (p<0.001), and MSD (p = 0.031) when compared to the no-tracking segmentation, but did not significantly increase the DSC (p = 0.294).

CONCLUSIONS

The accuracy of our cGAN segmentation method demonstrates the feasibility of this method for H&N cancer patients during RT. Accurate tumor segmentation of H&N tumors would allow for intrafraction monitoring methods to compensate for tumor motion during treatment, ensuring more accurate dose delivery and enabling better H&N cancer patient outcomes. This article is protected by copyright. All rights reserved.

Proton-to-photon comparative treatment planning guidelines for the Australian context

Proton-to-photon comparative treatment planning is a current requirement of Australian Government funding for patients to receive proton beam therapy (PBT) overseas, and a future requirement for Medicare funding of PBT in Australia. Because of the fundamental differences in treatment plan creation and evaluation between PBT and conventional radiation therapy with x-rays (XRT), there is the potential for a lack of consistency in the process of comparing PBT and XRT treatment plans. This may have an impact on patient eligibility assessment for PBT. The objective of these guidelines is to provide a practical reference document for centres performing proton-to-photon comparative planning and thereby facilitate national uniformity.

Standardising Breast Radiotherapy Structure Naming Conventions: A Machine Learning Approach

In progressing the use of big data in health systems, standardised nomenclature is required to enable data pooling and analyses. In many radiotherapy planning systems and their data archives, target volumes (TV) and organ-at-risk (OAR) structure nomenclature has not been standardised. Machine learning (ML) has been utilised to standardise volumes nomenclature in retrospective datasets. However, only subsets of the structures have been targeted. Within this paper, we proposed a new approach for standardising all the structures nomenclature by using multi-modal artificial neural networks. A cohort consisting of 1613 breast cancer patients treated with radiotherapy was identified from Liverpool & Macarthur Cancer Therapy Centres, NSW, Australia. Four types of volume characteristics were generated to represent each target and OAR volume: textual features, geometric features, dosimetry features, and imaging data. Five datasets were created from the original cohort, the first four represented different subsets of volumes and the last one represented the whole list of volumes. For each dataset, 15 sets of combinations of features were generated to investigate the effect of using different characteristics on the standardisation performance. The best model reported 99.416% classification accuracy over the hold-out sample when used to standardise all the nomenclatures in a breast cancer radiotherapy plan into 21 classes. Our results showed that ML based automation methods can be used for standardising naming conventions in a radiotherapy plan taking into consideration the inclusion of multiple modalities to better represent each volume.

Randomized, double-blind, placebo-controlled, crossover trial of oral doxycycline for epistaxis in hereditary hemorrhagic telangiectasia

Background

Vascular malformations in hereditary hemorrhagic telangiectasia (HHT) lead to chronic recurrent bleeding, hemorrhage, stroke, heart failure, and liver disease. There is great interest in identifying novel therapies for epistaxis in HHT given its associated morbidity and impact on quality of life. We aimed to measure the effectiveness of oral doxycycline for the treatment of epistaxis and explore mechanisms of action on angiogenic, inflammatory and pathway markers in HHT using a randomized controlled trial.

Methods

13 HHT patients with epistaxis were recruited from the Toronto HHT Center at St. Michael’s Hospital. Recruitment was stopped early due to COVID-19-related limitations. The study duration was 24 months. Patients were randomly assigned to the treatment-first or placebo-first study arm. We compared the change in weekly epistaxis duration and frequency, biomarkers, blood measurements, and intravenous iron infusion and blood transfusion requirements between treatment and placebo.

Results

There was no significant difference in the change in weekly epistaxis duration (p = 0.136) or frequency (p = 0.261) between treatment and placebo. There was no significant difference in the levels of MMP-9, VEGF, ANG-2, IL-6 or ENG with treatment. Hemoglobin levels were significantly higher (p = 0.0499) during treatment. Ferritin levels were not significantly different between treatment and placebo. There was no significant difference in RBC transfusions between treatment periods (p = 0.299).

Conclusion

Overall, our study did not demonstrate effectiveness of doxycycline as a treatment for epistaxis in patients with HHT, though the study was underpowered. Secondary analyses provided new observations which may help guide future trials in HHT.

Trial Registration ClinicalTrials.gov, NCT03397004. Registered 11 January 2018 – Prospectively registered, https://clinicaltrials.gov/ct2/show/NCT03397004

Supplementary Information

The online version contains supplementary material available at 10.1186/s13023-022-02539-8.

Infrastructure platform for privacy-preserving distributed machine learning development of computer-assisted theragnostics in cancer

INTRODUCTION

Emerging evidence suggests that data-driven support tools have found their way into clinical decision-making in a number of areas, including cancer care. Improving them and widening their scope of availability in various differing clinical scenarios, including for prognostic models derived from retrospective data, requires co-ordinated data sharing between clinical centres, secondary analyses of large multi-institutional clinical trial data, or distributed (federated) learning infrastructures. A systematic approach to utilizing routinely collected data across cancer care clinics remains a significant challenge due to privacy, administrative and political barriers.

METHODS

An information technology infrastructure and web service software was developed and implemented which uses machine learning to construct clinical decision support systems in a privacy-preserving manner across datasets geographically distributed in different hospitals. The infrastructure was deployed in a network of Australian hospitals. A harmonized, international ontology-linked, set of lung cancer databases were built with the routine clinical and imaging data at each centre. The infrastructure was demonstrated with the development of logistic regression models to predict major cardiovascular events following radiation therapy.

RESULTS

The infrastructure implemented forms the basis of the Australian computer-assisted theragnostics (AusCAT) network for radiation oncology data extraction, reporting and distributed learning. Four radiation oncology departments (across seven hospitals) in New South Wales (NSW) participated in this demonstration study. Infrastructure was deployed at each centre and used to develop a model predicting for cardiovascular admission within a year of receiving curative radiotherapy for non-small cell lung cancer. A total of 10417 lung cancer patients were identified with 802 being eligible for the model. Twenty features were chosen for analysis from the clinical record and linked registries. After selection, 8 features were included and a logistic regression model achieved an area under the receiver operating characteristic (AUROC) curve of 0.70 and C-index of 0.65 on out-of-sample data.

CONCLUSION

The infrastructure developed was demonstrated to be usable in practice between clinical centres to harmonize routinely collected oncology data and develop models with federated learning. It provides a promising approach to enable further research studies in radiation oncology using real world clinical data.

Evaluating incident learning systems and safety culture in two radiation oncology departments

INTRODUCTION

Radiation oncology patient pathways are complex. This complexity creates risk and potential for error to occur. Comprehensive safety and quality management programmes have been developed alongside the use of incident learning systems (ILSs) to mitigate risks and errors reaching patients. Robust ILSs rely on the safety culture (SC) within a department. The aim of this study was to assess perceptions and understanding of SC and ILSs in two closely linked radiation oncology departments and to use the results to consider possible quality improvement (QI) of department ILSs and SC.

METHODS

A survey to assess perceptions of SC and the currently used ILSs was distributed to radiation oncologists, radiation therapists and radiation oncology medical physicists in the two departments. The responses of 95 staff were evaluated (63% of staff). The findings were used to determine any areas for improvement in SC and local ILSs.

RESULTS

Differences were shown between the professional cohorts. Barriers to current ILS use were indicated by 67% of respondents. Positive SC was shown in each area assessed: 69% indicated the departments practised a no-blame culture. Barriers identified in one department prompted a QI project to develop a new reporting system and process, improve departmental learning and modify the overall ILS.

CONCLUSION

An understanding of SC and attitudes to ILSs has been established and used to improve ILS reporting, feedback on incidents, departmental learning and the QA program. This can be used for future comparisons as the systems develop.

Simultaneous measurements of myocardial glucose metabolism and extracellular volumes with hybrid PET/MRI using concurrent injections of Gd-DTPA and [18F]FDG

BACKGROUND

The aims of this study were to investigate the application of a constant infusion (CI) to mitigate the issue of constantly changing Gd-DTPA contrast levels in a bolus injection for extracellular volume (ECV) measurements by (a) comparing a CI alone to a bolus alone and a bolus followed by CI in healthy myocardium, (b) evaluating the impact of glucose suppression using heparin on ECV.

METHODS

Five healthy canine subjects were imaged to compare three different protocols for injecting Gd-DTPA and FDG: bolus alone, CI alone, bolus followed by CI. Suppression of myocardial glucose uptake was induced using a continuous infusion of 20% lipid at a rate of 0.25 mL·min-1·kg-1 as well as 2000 units of intravenous heparin injected 20 minutes prior to FDG/Gd-DTPA injection.

RESULTS

There was no significant effect on ECV measurement when heparin was used for glucose suppression at equilibrium irrespective of infusion protocol). Measurements of ECV in myocardium, regardless of infusion protocol showed no significant difference at all time points (P = 0.21) prior to washout.

CONCLUSIONS

The suppression of myocardial uptake of [18F]FDG with heparin did not alter the determination of myocardial ECV though a larger sample size may show differences. Further, the infusion protocol (bolus or constant infusion) had no effect on the calculated ECV.

Tracking the progress of inflammation with PET/MRI in a canine model of myocardial infarction

BACKGROUND

Following myocardial infarction, tissue undergoes pathophysiological changes involving inflammation and scar tissue formation. However, little is known about the pathophysiology and prognostic significance of any corresponding changes in remote myocardium. The aim of this study was to investigate the potential application of a combined constant infusion of 18F-FDG and Gd-DTPA to quantitate inflammation and extracellular volume (ECV) from 3 to 40 days after myocardial infarction.

METHODS

Eight canine subjects were imaged at multiple time points following induction of an MI with a 60-minute concurrent constant infusion of Gd-DTPA and 18F-FDG using a hybrid PET/MRI scanner.

RESULTS

There was a significant increase in ECV in remote myocardium on day 14 post-MI (P = .034) and day 21 (P = .021) compared to the baseline. ECV was significantly elevated in the infarcted myocardium compared to remote myocardium at all time points post-MI (days 3, 7, 14, 21, and 40) (P < .001) while glucose uptake was also increased within the infarct on days 3, 7, 14, and 21 but not 40.

CONCLUSIONS

The significant increase in ECV in remote tissue may be due to an ongoing inflammatory process in the early weeks post-infarct.

Safety culture and incident learning systems in radiation oncology: Staff perceptions across Australia and New Zealand

INTRODUCTION

Radiation therapy has a highly complex pathway and uses detailed quality assurance protocols and incident learning systems (ILSs) to mitigate risk; however, errors can still occur. The safety culture (SC) in a department influences its commitment and effectiveness in maintaining patient safety.

METHODS

Perceptions of SC and knowledge and understanding of ILSs and their use were evaluated for radiation oncology staff across Australia and New Zealand (ANZ). A validated healthcare survey tool (the Hospital Survey on Patient Safety Culture) was used, with additional specialty-focussed supporting questions. A total of 220 radiation oncologists, radiation therapists and radiation oncology medical physicists participated.

RESULTS

An overall positive SC was indicated, with strength in teamwork (83.7%), supervisor/manager/leader support (83.3%) and reporting events (77.1%). The weakest areas related to communication about error (63.9%), hospital-level management support (60.5%) and handovers and information exchange (58.0%). Barriers to ILS use included 'it takes too long' and that many respondents must use multiple reporting systems, including mandatory hospital-level systems. These are generally not optimal for specific radiation oncology needs. Varied understanding was indicated of what and when to report.

CONCLUSION

The findings report the ANZ perspective on ILS and SC, highlighting weaknesses, barriers and areas for further investigation. Differences observed in some areas suggest that a unified state, national or bi-national ILS specific to radiation oncology might eliminate multiple reporting systems and reduce reporting time. It could also provide more consistent and robust approaches to incident reporting, information sharing and analysis.

Implementation of the Australian Computer-Assisted Theragnostics (AusCAT) network for radiation oncology data extraction, reporting and distributed learning

INTRODUCTION

There is significant potential to analyse and model routinely collected data for radiotherapy patients to provide evidence to support clinical decisions, particularly where clinical trials evidence is limited or non-existent. However, in practice there are administrative, ethical, technical, logistical and legislative barriers to having coordinated data analysis platforms across radiation oncology centres.

METHODS

A distributed learning network of computer systems is presented, with software tools to extract and report on oncology data and to enable statistical model development. A distributed or federated learning approach keeps data in the local centre, but models are developed from the entire cohort.

RESULTS

The feasibility of this approach is demonstrated across six Australian oncology centres, using routinely collected lung cancer data from oncology information systems. The infrastructure was used to validate and develop machine learning for model-based clinical decision support and for one centre to assess patient eligibility criteria for two major lung cancer radiotherapy clinical trials (RTOG-9410, RTOG-0617). External validation of a 2-year overall survival model for non-small cell lung cancer (NSCLC) gave an AUC of 0.65 and C-index of 0.62 across the network. For one centre, 65% of Stage III NSCLC patients did not meet eligibility criteria for either of the two practice-changing clinical trials, and these patients had poorer survival than eligible patients (10.6 m vs. 15.8 m, P = 0.024).

CONCLUSION

Population-based studies on routine data are possible using a distributed learning approach. This has the potential for decision support models for patients for whom supporting clinical trial evidence is not applicable.

Anatomic Trends and Directions in Periorbital Aesthetic Surgery

The anatomy of the eyelids and periorbital region is delicate. The individual anatomic variations determine each person's eyelid appearance and function. It is essential that every surgeon that evaluates and treats the aesthetic conditions of patients desiring periorbital enhancement understands the association of anatomy and diagnosis. Each periorbital aesthetic diagnosis has an anatomic basis, and knowledge of the applied anatomy allows a targeted treatment plan. This article outlines the layered anatomy with its clinical significance for the eyelids and periorbital region. Specific examples are used to illustrate the applied anatomy. A contemporary treatment plan for each anatomic problem is given.

Deforming to Best Practice: Key considerations for deformable image registration in radiotherapy

Image registration is a process that underlies many new techniques in radiation oncology - from multimodal imaging and contour propagation in treatment planning to dose accumulation throughout treatment. Deformable image registration (DIR) is a subset of image registration subject to high levels of complexity in process and validation. A need for local guidance to assist in high-quality utilisation and best practice was identified within the Australian community, leading to collaborative activity and workshops. This report communicates the current limitations and best practice advice from early adopters to help guide those implementing DIR in the clinic at this early stage. They are based on the state of image registration applications in radiotherapy in Australia and New Zealand (ANZ), and consensus discussions made at the 'Deforming to Best Practice' workshops in 2018. The current status of clinical application use cases is presented, including multimodal imaging, automatic segmentation, adaptive radiotherapy, retreatment, dose accumulation and response assessment, along with uptake, accuracy and limitations. Key areas of concern and preliminary suggestions for commissioning, quality assurance, education and training, and the use of automation are also reported. Many questions remain, and the radiotherapy community will benefit from continued research in this area. However, DIR is available to clinics and this report is intended to aid departments using or about to use DIR tools now.

Relationship Between Vertical Glabellar Lines and the Supratrochlear and Supraorbital Arteries

BACKGROUND

Glabellar soft tissue filler injections have been shown to be associated with a high risk of causing injection-related visual compromise.

OBJECTIVES

The aim of this study was to identify the course of the superficial branch of the supratrochlear and of the deep branch of the supraorbital artery in relation to the ipsilateral vertical glabellar line and to test whether an artery is located deep to this line.

METHODS

Forty-one healthy volunteers with a mean age of 26.17 [9.6] years and a mean BMI of 23.09 [2.3] kg/m2 were analyzed. Ultrasound imaging was applied to measure the diameters, distance from skin surface, distance between the midline, distance between vertical glabella lines, and the cutaneous projection of the supratrochlear/supraorbital arteries at rest and upon frowning.

RESULTS

The mean distance between the superficial branch of the supratrochlear artery and the ipsilateral vertical glabellar line was 10.59 [4.0] mm in males and 8.21 [4.0] mm in females, whereas it was 22.38 [5.5] mm for the supraorbital artery in males and 20.73 [5.6] mm in females. Upon frowning, a medial shift in supratrochlear arterial position of 1.63 mm in males and 1.84 mm in females and of 3.9 mm in supraorbital arterial position for both genders was observed. The mean depth of the supratrochlear artery was 3.34 [0.6] mm at rest, whereas the depth of the supraorbital artery was 3.54 [0.8] mm.

CONCLUSIONS

The hypothesis that injecting soft tissue fillers next to the vertical glabellar line is safe because the supratrochlear artery courses deep to the crease should be rejected. Additionally, the glabella and the supraorbital region should be considered as an area of mobile, rather than static, soft tissues.

Demystifying the Deep Plane Facelift: What It Means Anatomically and Why It Works

Rhytidectomy is a common procedure performed by facial plastic surgeons. On well-selected patients, rhytidectomy rejuvenates the aging face by repositioning soft tissues and improving facial shape. The fundamental goal of rhytidectomy, or facelift surgery, is to provide a more youthful facial appearance by elevating soft tissues that often descend with aging. The success and longevity of any rhytidectomy procedure are based on the individual patient's anatomy and aging and on the mobilization, elevation, and fixation of the soft tissues during the facelift procedure. Although surgeons often use many terms to describe a given facelift technique, anatomical terms are best used to name the facelift procedure, as the plane of dissection and the vector of elevation are what determines the end result. This paper attempts to simplify and demystify the deep plane facelift procedure and to describe the anatomy that makes this technique successful.

Morphing as a Selection Tool in the Rhinoplasty Consult: A Cross-Sectional Study

Despite the recognized value of morphing in the literature, this preoperative tool has never been studied in the context of selection process in rhinoplasty. The main purpose of this article is to identify the use of morphing as a filter for unsuitable patients, the attrition rate from the initial consultation to surgery, and whether patients' appreciation on morphing influence their decision-making process. Three-hundred thirty-four consecutive patients, seeking rhinoplasty, underwent two-dimensional computer imaging and completed a 14-question survey about their opinion on morphing. Based on the presence or absence of patient/physician consensus on the expected outcomes during simulation, patients were divided into accepted or rejected candidates for surgery. Accepted candidates were scheduled for rhinoplasty and subdivided into those who underwent surgery, those who postponed their surgery (static), and those who cancelled their procedure. Their responses to the survey were compared between different patients' categories. Forty-four patients (13.2%) were rejected for rhinoplasty since consensus was not achieved during morphing. From 290 accepted patients, 178 underwent their operation (53.3%), 74 patients (22.1%) postponed their rhinoplasty, and 38 (11.4%) cancelled their surgery. Fifty-seven percent of rejected patients and 42% of the static group were not satisfied with the proposed results of morphing, in contrast with 16% of the operated group. Sixty-four percent of rejected patients, and 47% of the static group were not reassured after morphing, compared with 26% of the operated group. Presence or absence of consensus during morphing can guide the surgeon regarding a given patients' suitability for surgery. Patient satisfaction and reassurance with the morphed images can be a good predictor of patients who will proceed to surgery, calling attention to the value of morphing as a selection tool for surgeons and patients alike.

The Tripod Concept of the Upper Nasal Third

Importance

The tripod theory of the upper nasal third parallels the concept of the well-known nasal tip tripod. We are evaluating the idea that one can simply alter the upper nasal angles reliably without the complex physics associated with the nasal tip to achieve a pleasing cosmetic result.

Objective

To describe a concept related to the well-known tripod theory with extrapolation to the upper nasal third as it pertains to cosmetic rhinoplasty.

Design, Setting, and Participants

This is a prospective study in which lateral photographs of 3 women who had not undergone surgery (age range, 20-50 years) were selected for digital manipulation of the nasal radix with subsequent alteration of the nasofrontal and nasofacial angles via imaging software. The altered images were analyzed by 20 blinded individuals between July 2009 and June 2017 to assess how changes in the height of the nasal dorsum and radix alone affect nasal appearance and the perception of ideal nasal angles. The study took place at a tertiary center, and the patients chosen for evaluation had nasal architecture that only required subtle changes rather than structure that demonstrated glaringly obvious overprojection or underprojection and rotation or a large dorsal bony hump. Analysis began June 2018.

Main Outcomes and Measures

Overall trend in recognition of objective and subjective alterations in projection and rotation for the rhinoplasty- and non-rhinoplasty-trained evaluators.

Results

Ten medically trained and 10 lay individuals (13 women [65%]; mean [SD] age, 38 [8.6] years) analyzed digitally manipulated photographs of 3 women (age range, 20-50 years) who had not undergone surgery. Lay individuals were more likely to choose an ideal nasal profile based on surrounding facial architecture (28 of 30 [93%]), while individuals with rhinoplasty training tended to separate the ideal nose from the surrounding face (18 of 30 [60%]) (P < .001). Projection was consistently and accurately recognized as being altered by both rhinoplasty-trained and lay individuals (95% CI, -0.18 to 0.38; P = .60 and 95% CI, -0.26 to 0.33; P > .99 for most and least projected), whereas subjective changes in rotation were significantly more elusive to the lay individual (95% CI, -0.04 to 0.52; P = .12 and 95% CI, 0.11 to 0.65; P = .01 for most and least rotated).

Conclusions and Relevance

Predictable and consistent aesthetic results are the primary aim in rhinoplasty. Alterations in the upper nasal tripod are more reliable with extrapolated healing than with the tripod of the nasal tip. Ultimately, simple alteration of the upper nasal third can result in an improved nasal profile without specific alteration of tip architecture.

Level of Evidence

NA.

Evaluation of dual energy CT and iterative metal artefact reduction (iMAR) for artefact reduction in radiation therapy

Metal artefacts pose a common problem in single energy computed tomography (SECT) images used for radiotherapy. Virtual monoenergetic (VME) images constructed with dual energy computed tomography (DECT) scans can be used to reduce beam hardening artefacts. Dual energy metal artefact reduction is compared and combined with iterative metal artefact reduction (iMAR) to determine optimal imaging strategies for patients with metal prostheses. SECT and DECT scans were performed on a Siemens Somatom AS-64 Slice CT scanner. Images were acquired of a modified CIRS pelvis phantom with 6, 12, 20 mm diameter stainless steel rods and VME images reconstructed at 100, 120, 140 and 190 keV. These were post-reconstructed with and without the iMAR algorithm. Artefact reduction was measured using: (1) the change in Hounsfield Unit (HU) with and without metal artefact reduction (MAR) for 4 regions of interest; (2) the total number of artefact pixels, defined as pixels with a difference (between images with metal rod and without) exceeding a threshold; (3) the difference in the mean pixel intensity of the artefact pixels. DECT, SECT + iMAR and DECT + iMAR were compared. Both SECT + iMAR and DECT + iMAR offer successful MAR for phantom simulating unilateral hip prosthesis. DECT gives minimal artefact reduction over iMAR alone. Quantitative metrics are advantageous for MAR analysis but have limitations that leave room for metric development.

Perceived Preparedness of Facial Plastic Surgery Fellows Over Time: A Survey of AAFPRS Fellowship Directors

OBJECTIVE

Assess the effects of American Council for Graduate Medical Education (ACGME) resident work hour restrictions on the preparedness of incoming facial plastic surgery fellows as assessed by American Academy of Facial Plastic and Reconstructive Surgery (AAFPRS) fellowship directors.

METHODS

Observational survey study evaluating the perception of ACGME resident duty hour change on resident surgical and clinical skills from fellowship directors of AAFPRS fellowship programs in the US. A cross-sectional survey was sent to 47 fellowship directors of AAFPRS fellowship programs. Perceived change in resident clinical and surgical skills were measured using a 5-point Likert scale (1 = significantly improved, 2 = improved, 3 = neither improved nor worsened, 4 = worsened, 5 = significantly worsened) to evaluate 15 benchmarks.

RESULTS

Responses received from 36 fellowship directors. The results indicate no statistically significant perceived trend of ACGME duty hour reform on fellows for AAFPRS fellowships among fellowship directors. However, cohort analysis demonstrated that fellowship directors with more than 10 years of service perceived a more negative impact in 2 clinical benchmarks (assessment/planning and basic exposure) over time.

CONCLUSIONS

The study results appear to show no significant perceived trend over time on the effect of duty hour reform on fellows for AAFPRS fellowships among fellowship directors. However, there are some apparent opinion differences between fellowship directors separated by years of service, with more negative perceptions noted in 2 clinical areas by those with more than 10 years of service. This study is in line with the more recent literature that suggests a trend toward a less negative perception of the duty hour change. This may suggest resident education is adapting to the ACGME duty hour regulations.

Simulating Transplant Small-for-size Grafts Using Human Liver Monosegments: The Impact of Portal Perfusion Pressure

Small-for-size-liver grafts (SFSG) in adult transplant recipients have elevated risk of graft failure, limiting its application in clinical liver transplantation. Relevant preclinical model of SFSG is lacking. Relevant to deceased-donor split liver transplant and living-donor liver transplant in adult recipients, in this study, we present our initial characterization of SFSG model using monosegments of a discarded human donor liver.

A CBCT study of the gravity-induced movement in rotating rabbits

Fixed-beam radiotherapy systems with subjects rotating about a longitudinal (horizontal) axis are subject to gravity-induced motion. Limited reports on the degree of this motion, and any deformation, has been reported previously. The purpose of this study is to quantify the degree of anatomical motion caused by rotating a subject around a longitudinal axis, using cone-beam CT (CBCT). In the current study, a purpose-made longitudinal rotating was aligned to a Varian TrueBeam kV imaging system. CBCT images of three live rabbits were acquired at fixed rotational offsets of the cradle. Rigid and deformable image registrations back to the original position were used to quantify the motion experienced by the subjects under rotation. In the rotation offset CBCTs, the mean magnitude of rigid translations was 5.7  ±  2.7 mm across all rabbits and all rotations. The translation motion was reproducible between multiple rotations within 2.1 mm, 1.1 mm, and 2.8 mm difference for rabbit 1, 2, and 3, respectively. The magnitude of the mean and absolute maximum deformation vectors were 0.2  ±  0.1 mm and 5.4  ±  2.0 mm respectively, indicating small residual deformations after rigid registration. In the non-rotated rabbit 4DCBCT, respiratory diaphragm motion up to 5 mm was observed, and the variation in respiratory motion as measured from a series of 4DCBCT scans acquired at each rotation position was small. The principle motion of the rotated subjects was rigid translational motion. The deformation of the anatomy under rotation was found to be similar in scale to normal respiratory motion. This indicates imaging and treatment of rotated subjects with fixed-beam systems can use rigid registration as the primary mode of motion estimation. While the scaling of deformation from rabbits to humans is uncertain, these proof-of-principle results indicate promise for fixed-beam treatment systems.

Can the Otago falls prevention program be delivered by video? A feasibility study

Objectives

We assessed the feasibility of delivering the Otago Exercise Programme (OEP) via an interactive DVD (ie, OEP-DVD) in combination with monthly physical therapist phone calls to older adults.

Design

This pre-post (baseline and 6-month follow-up) study included an intervention group (n=61) based in a rural location and a control group (n=21) based in a city.

Setting

Sechelt and Vancouver, British Columbia.

Participants

82 community-dwelling adults ≥75 years.

Intervention

Individuals in the intervention group received the OEP-DVD and were instructed to do the exercises 3 times a week after their initial home physical therapist visit for 6 months.

Primary and secondary outcomes

Feasibility was ascertained by withdrawal rate and compliance to the OEP-DVD. The number of participants and the frequency (ie, number of times weekly) they performed the OEP exercises and walking were used to estimate compliance. The potential benefit of the OEP-DVD on falls risk profile (Physiological Profile Assessment (PPA)) and mobility were examined by comparing the change in the intervention group compared with the control group. Self-reported compliance to the exercise programme was assessed by monthly returned diary.

Results

Of the 82 participants, 2 withdrew from the OEP-DVD group and none withdrew from the control group. We obtained compliance data on 72% of participants in the intervention group. The mean OEP-DVD compliance was 87% and the mean walking compliance was 166%. After adjusting for baseline PPA, baseline age, sex, baseline comorbidities, baseline cognitive status and baseline falls-related self-efficacy, there was a significant between-group improvement in the overall PPA score (OEP group pre-PPA to post-PPA score: 0.79±1.2 to 0.7±0.9; p<0.05) at study completion.

Conclusions

Although the OEP-DVD resulted in significant reductions in falls risk among community-dwelling older adults, there was a notable loss to follow-up limiting the feasibility of this approach.

Update on Canine and Feline Blood Donor Screening for Blood-Borne Pathogens

An update on the 2005 American College of Veterinary Internal Medicine (ACVIM) Consensus Statement on blood donor infectious disease screening was presented at the 2015 ACVIM Forum in Indianapolis, Indiana, followed by panel and audience discussion. The updated consensus statement is presented below. The consensus statement aims to provide guidance on appropriate blood‐borne pathogen testing for canine and feline blood donors in North America.

ATX-101 for reduction of submental fat: A phase III randomized controlled trial

BACKGROUND

ATX-101, an injectable form of deoxycholic acid, causes adipocytolysis when injected subcutaneously into fat.

OBJECTIVE

We sought to evaluate the efficacy and safety of ATX-101.

METHODS

In this phase III trial (REFINE-2), adults dissatisfied with their moderate or severe submental fat (SMF) were randomized to ATX-101 or placebo. Coprimary end points, evaluated at 12 weeks after last treatment, were composite improvements of 1 or more grades and 2 or more grades in SMF observed on both the validated Clinician- and Patient-Reported SMF Rating Scales. Other end points included magnetic resonance imaging-based assessment of submental volume, assessment of psychological impact of SMF, and additional patient-reported outcomes.

RESULTS

Among those treated with ATX-101 or placebo (n = 258/treatment group), 66.5% versus 22.2%, respectively, achieved a composite improvement of 1 or more grades (Mantel-Haenszel risk ratio 2.98; 95% confidence interval 2.31-3.85) and 18.6% versus 3.0% achieved a composite improvement of 2 or more grades in SMF (Mantel-Haenszel risk ratio 6.27; 95% confidence interval 2.91-13.52; P < .001 for both). Those treated with ATX-101 were more likely to achieve submental volume reduction confirmed by magnetic resonance imaging, greater reduction in psychological impact of SMF, and satisfaction with treatment (P < .001 for all). Overall, 85.7% of adverse events in the ATX-101 group and 76.9% in the placebo group were localized to the injection site.

LIMITATIONS

Follow-up was limited to 44 weeks.

CONCLUSION

ATX-101 is an alternative treatment for SMF reduction.

The benefits of newborn screening for cystic fibrosis: The Canadian experience

BACKGROUND

The impact of newborn screening (NBS) for cystic fibrosis (CF) on early indicators of long-term health was evaluated in the context of government-sponsored healthcare and access to current therapies.

METHODS

Using data from the Canadian CF Registry between 2008 and 2013, we compared the rates of respiratory infections and markers of nutritional status in those diagnosed through NBS to those who were diagnosed clinically within the same time period using Mann-Whitney and Fischer's exact test as appropriate.

RESULTS

The study included 303 subjects, 201 in the NBS group and 102 in the non-NBS group. NBS patients were diagnosed earlier and had their first clinic visit at a younger age. Pancreatic insufficiency was less common in NBS patients. The incidence of Pseudomonas aeruginosa and Staphylococcus aureus were lower in NBS patients. After adjusting for age at clinic visit, gender, pancreatic status, and Pseudomonas aeruginosa infection status, mean z-scores for weight-for-age and height-for-age were higher in NBS patients, with no differences in BMI-for-age.

CONCLUSIONS

NBS programs for CF lead to improved long-term health outcomes for the CF population.