MR Lymphangiography in Lymphatic Disorders: Clinical Applications, Institutional Experience, and Practice Development.

Lymphatic flow and anatomy can be challenging to study, owing to variable lymphatic anatomy in patients with diverse primary or secondary lymphatic pathologic conditions and the fact that lymphatic imaging is rarely performed in healthy individuals. The primary components of the lymphatic system outside the head and neck are the peripheral, retroperitoneal, mesenteric, hepatic, and pulmonary lymphatic systems and the thoracic duct. Multiple techniques have been developed for imaging components of the lymphatic system over the past century, with trade-offs in spatial, temporal, and contrast resolution; invasiveness; exposure to ionizing radiation; and the ability to obtain information on dynamic lymphatic flow. More recently, dynamic contrast-enhanced (DCE) MR lymphangiography (MRL) has emerged as a valuable tool for imaging both lymphatic flow and anatomy in a variety of congenital and acquired primary or secondary lymphatic disorders. The authors provide a brief overview of lymphatic physiology, anatomy, and imaging techniques. Next, an overview of DCE MRL and the development of an MRL practice and workflow in a hybrid interventional MRI suite incorporating cart-based in-room US is provided, with an emphasis on multidisciplinary collaboration. The spectrum of congenital and acquired lymphatic disorders encountered early in an MRL practice is provided, with emphasis on the diversity of imaging findings and how DCE MRL can aid in diagnosis and treatment of these patients. Methods such as DCE MRL for assessing the hepatic and mesenteric lymphatic systems and emerging technologies that may further expand DCE MRL use such as three-dimensional printing are introduced. ©RSNA, 2024 Test Your Knowledge questions for this article are available in the supplemental material.

Patient-specific Implants Improve Volumetric Surgical Accuracy Compared to Stock Reconstruction Plates in Modern Pardigm Virtual Surgical Planning of Fibular Free Flaps for Head and Neck Reconstruction.

BACKGROUND: Virtual surgical planning (VSP) for composite microvascular free flaps has become standard of care for oncologic head and neck reconstruction. Controversy remains as to the use of three-dimensional (3D)-printed titanium patient-specific implants (PSIs) versus hand-bent stock reconstruction plates. Proponents of PSIs cite improved surgical accuracy, reduced operative times, and improved clinical outcomes. Detractors purport increased cost associated with PSIs and presumed equivalent accuracy with less expensive stock plates. PURPOSE: The study purpose was to measure and compare the 3D-volumetric accuracy of PSI versus stock reconstruction plates among subjects undergoing VSP-guided mandibular fibular free flap reconstruction. STUDY DESIGN, SETTING, SAMPLE: A retrospective cohort study of subjects undergoing VSP-guided fibular free flap reconstructions at Mayo Clinic between 2016 and 2023 was performed. Subjects were excluded for non-VSP guidance, midfacial reconstruction, nonfibular free flaps, and lack of requisite study variables. PREDICTOR VARIABLE: The primary predictor was the type of reconstruction plate utilized (PSI vs stock plate). MAIN OUTCOME VARIABLE: The main outcome was volumetric surgical accuracy of the final reconstruction compared to the preoperative surgical plan by root mean square error (RMSE) calculation. Lower RMSE values indicated a higher surgical accuracy. COVARIATES: Covariates included age, sex, race, smoking status, American Society of Anesthesiologists Physical Status Classification System, Charlson Comorbidity Index, preoperative diagnosis, and number of fibular segments. ANALYSES: Differences in surgical accuracy were assessed between preoperative and postoperative segmented scans using volumetric overlays from which RMSE values were calculated. Univariate and multivariate modeling of plate type to RMSE calculation was performed. Statistical significance set to P < .05. RESULTS: Total of 130 subjects were identified, 105 PSI and 25 stock plates. Calculated mean RMSE in millimeters (mm) for stock plates was 1.46 (standard deviation: 0.33) and 1.15 (standard deviation: 0.36) for PSIs. Univariate modeling demonstrated a statistically significant difference in RMSE of 0.31 (95% confidence interval: 0.16-0.47) (P < .001) equating to a 21.2% (P < .001) improved volumetric surgical accuracy for PSIs. The association of improved volumetric accuracy with PSIs has been maintained in all multivariate models controlling for confounding. CONCLUSION AND RELEVANCE: In modern era VSP-guided head and neck fibular free flap reconstruction, patient-specific 3D-printed titanium implants confer a statistically significant improvement in volumetric surgical accuracy over stock reconstruction plates.

Creation and Validation of a Novel 3-Dimensional Pediatric Hip Ultrasound Model.

OBJECTIVES: The aim of this study was to create and validate a 3-dimensional (3D) ultrasound model with normal and abnormal pediatric hip joint anatomy that is comparable to a pediatric hip joint in appearance and anatomy and replicates sonographic characteristics of a pediatric hip joint. METHODS: A 3D rendering of the bone and soft tissue was created from a computed tomography pelvic scan of a pediatric patient. This rendering was modified to include a unilateral joint effusion. The bone was 3D printed with a photopolymer plastic, whereas the soft tissue was cast with a silicone mixture in a 3D-printed mold. The effusion was simulated by injecting saline into the soft tissue cavity surrounding the bone. The ultrasound model was validated by pediatric point-of-care ultrasonographers at an international pediatric ultrasound conference. RESULTS: A pediatric hip ultrasound model was developed that simulates both normal and abnormal pediatric hip joint anatomy, each with an appropriately sized, measurable joint effusion. Validation by pediatric point-of-care ultrasonographers showed that the key aspects of a normal pediatric hip joint (femoral physis, sloped femoral neck, and adequate soft tissue) with an identifiable and measurable effusion were included in the ultrasound model. CONCLUSIONS: In this study, we successfully created a cost-effective, reusable, and reproducible 3D pediatric hip ultrasound model. The majority of pediatric point-of-care ultrasonographers who evaluated the model agreed that this model is comparable to a pediatric patient for the purpose of teaching ultrasound skills and joint space measurement.

Development and validation of a recursive partitioning analysis-based pretreatment decision-making tool identifying ideal candidates for spine stereotactic body radiation therapy.

BACKGROUND: This study was aimed at developing and validating a decision-making tool predictive of overall survival (OS) for patients receiving stereotactic body radiation therapy (SBRT) for spinal metastases. METHODS: Three hundred sixty-one patients at one institution were used for the training set, and 182 at a second institution were used for external validation. Treatments most commonly involved one or three fractions of spine SBRT. Exclusion criteria included proton therapy and benign histologies. RESULTS: The final model consisted of the following variables and scores: Spinal Instability Neoplastic Score (SINS) ≥ 6 (1), time from primary diagnosis < 21 months (1), Eastern Cooperative Oncology Group (ECOG) performance status = 1 (1) or ECOG performance status > 1 (2), and >1 organ system involved (1). Each variable was an independent predictor of OS (p < .001), and each 1-point increase in the score was associated with a hazard ratio of 2.01 (95% confidence interval [CI], 1.79-2.25; p < .0001). The concordance value was 0.75 (95% CI, 0.71-0.78). The scores were discretized into three groups-favorable (score = 0-1), intermediate (score = 2), and poor survival (score = 3-5)-with 2-year OS rates of 84% (95% CI, 79%-90%), 46% (95% CI, 36%-59%), and 21% (95% CI, 14%-32%), respectively (p < .0001 for each). In the external validation set (182 patients), the score was also predictive of OS (p < .0001). Increasing SINS was predictive of decreased OS as a continuous variable (p < .0001). CONCLUSIONS: This novel score is proposed as a decision-making tool to help to optimize patient selection for spine SBRT. SINS may be an independent predictor of OS.

A Radiologist's Guide to the 2021 WHO Central Nervous System Tumor Classification: Part 2-Newly Described and Revised Tumor Types.

The fifth edition of the World Health Organization classification of tumors of the central nervous system (CNS), published in 2021, introduces major shifts in the classification of brain and spine tumors. These changes were necessitated by rapidly increasing knowledge of CNS tumor biology and therapies, much of which is based on molecular methods in tumor diagnosis. The growing complexity of CNS tumor genetics has required reorganization of tumor groups and acknowledgment of new tumor entities. For radiologists interpreting neuroimaging studies, proficiency with these updates is critical in providing excellent patient care. This review will focus on new or revised CNS tumor types and subtypes, beyond infiltrating glioma (described in part 1 of this series), with an emphasis on imaging features.

A clinical primer for the glymphatic system.

The complex and dynamic system of fluid flow through the perivascular and interstitial spaces of the CNS has new-found implications for neurological diseases. CSF movement throughout the CNS parenchyma is more dynamic than could be explained via passive diffusion mechanisms alone. Indeed, a semistructured glial-lymphatic (glymphatic) system of astrocyte-supported extracellular perivascular channels serves to directionally channel extracellular fluid, clearing metabolites and peptides to optimize neurological function. Clinical studies of the glymphatic network have to date proven challenging, with most data gleaned from rodent models and post-mortem investigations. However, increasing evidence suggests that disordered glymphatic function contributes to the pathophysiology of CNS ageing, neurodegenerative disease and CNS injuries, as well as normal pressure hydrocephalus. Unlocking such pathophysiology could provide important avenues towards novel therapeutics. We here provide a multidisciplinary overview of glymphatics and critically review accumulating evidence regarding its structure, function and hypothesized relevance to neurological disease. We highlight emerging technologies of relevance to the longitudinal evaluation of glymphatic function in health and disease. Finally, we discuss the translational opportunities and challenges of studying glymphatic science.

Interventional radiology in obstetric patients: A population-based record linkage study of use and outcomes.

INTRODUCTION: Interventional radiology (IR) is a technique for controlling hemorrhage and preserving fertility for women with serious obstetric conditions such as placenta accreta spectrum (PAS) or postpartum hemorrhage. This study examined maternal, pregnancy and hospital characteristics and outcomes for women receiving IR in pregnancy and postpartum. MATERIAL AND METHODS: A population-based record linkage study was conducted, including all women who gave birth in hospital in New South Wales or the major tertiary hospital in the neighboring Australian Capital Territory, Australia, between 2003 and 2019. Data were obtained from birth and hospital records. Characteristics and outcomes of women who underwent IR in pregnancy or postpartum are described. Outcomes following IR were compared in a high-risk cohort of women: those with PAS who had a planned cesarean with hysterectomy. Women were grouped by those who did and those who did did not have IR and were matched using propensity score and other factors. RESULTS: We identified IR in 236 pregnancies of 1 584 708 (15.0 per 100 000), including 208 in the delivery and 26 in a postpartum admission. Two-thirds of women receiving IR in the birth admission received a transfusion of red cells or blood products, 28% underwent hysterectomy and 12.5% were readmitted within 6 weeks. Other complications included: severe maternal morbidity (29.8%), genitourinary tract trauma/repair (17.3%) and deep vein thrombosis/pulmonary embolism (4.3%). Outcomes for women with PAS who underwent planned cesarean with hysterectomy were similar for those who did and did not receive IR, with a small reduction in transfusion requirement for those who received IR. CONCLUSIONS: Interventional radiology is infrequently used in pregnant women. In our study it was performed at a limited number of hospitals, largely tertiary centers, with the level of adverse outcomes reflecting use in a high-risk population. For women with PAS undergoing planned cesarean with hysterectomy, most outcomes were similar for those receiving IR and those not receiving IR, but IR may reduce bleeding.

That which is unseen: 3D printing for pediatric cerebrovascular education.

INTRODUCTION: Pediatric cerebrovascular lesions are very rare and include aneurysms, arteriovenous malformations (AVM), and vein of Galen malformations (VOGM). OBJECTIVE: To describe and disseminate a validated, reproducible set of 3D models for optimization of neurosurgical training with respect to pediatric cerebrovascular diseases METHODS: All pediatric cerebrovascular lesions treated at our institution with adequate imaging studies during the study period 2015-2020 were reviewed by the study team. Three major diagnostic groups were identified: aneurysm, AVM, and VOGM. For each group, a case deemed highly illustrative of the core diagnostic and therapeutic principles was selected by the lead and senior investigators for printing (CSG/JM). Files for model reproduction and free distribution were prepared for inclusion as Supplemental Materials. RESULTS: Representative cases included a 7-month-old female with a giant left MCA aneurysm; a 3-day-old male with a large, complex, high-flow, choroidal-type VOGM, supplied from bilateral thalamic, choroidal, and pericallosal perforators, with drainage into a large prosencephalic vein; and a 7-year-old male with a left frontal AVM with one feeding arterial vessel from the anterior cerebral artery and one single draining vein into the superior sagittal sinus CONCLUSION: Pediatric cerebrovascular lesions are representative of rare but important neurosurgical diseases that require creative approaches for training optimization. As these lesions are quite rare, 3D-printed models and open source educational materials may provide a meaningful avenue for impactful clinical teaching with respect to a wide swath of uncommon or unusual neurosurgical diseases.

Virtual surgical planning and mirrored, 3-dimensionally printed guides for corrective clavicle osteotomies in clavicle malunions and nonunions.

BACKGROUND: The objective of this study was to retrospectively review clinical and radiographic outcomes of patients who underwent corrective osteotomies for clavicle malunion and internal fixation for nonunion using a combination of virtual surgical planning, patient-specific 3-dimensional (3D)-printed clavicles, and 3D-printed cutting guides manufactured at the point of care. METHODS: Between 2015 and 2021, 18 patients underwent corrective osteotomy for a clavicle malunion (7 shoulders) or internal fixation for a clavicle nonunion (11 shoulders). There were 11 male and 7 female individuals with an average patient age of 43.9 (range 19-76) years. All patients underwent computed tomography evaluation of both clavicles. The DICOM files were manually segmented, virtual surgical planning was performed selectively using commercially available software, and a mirrored version of the normal clavicle was 3D printed along with a 3D-printed replica of the affected clavicle. Three-dimensionally printed mirrored clavicles were used in all cases to ensure adequate restoration of the shape and length of the clavicle and to precontour fixation plates. Virtual surgical planning and 3D-printed cutting guides for osteotomy were used in 4 of 18 (22%) patients. Either cancellous or structural intercalary bone grafting was used in 15 of 18 (83%) cases. Patients were contacted postoperatively to determine clinical outcome scores. Preoperative, early postoperative, and late postoperative radiographs were reviewed to assess for union and complications. The average follow-up time was 24.9 months. RESULTS: Radiographic evaluation at the most recent follow-up demonstrated adequate restoration of length and successful union for all shoulders. There were no complications or reoperations. Postoperative patient-reported outcomes could be obtained in 16 of 18 (88.9%) patients. At the most recent follow-up, the mean visual analog scale for pain was 2.38 points (range, 1-7), the mean shoulder American Shoulder and Elbow Surgeons score was 73.2 points (range, 25-100), and the mean Patient-Reported Outcome Measurement Information System Upper Extremity score was 26 points (range, 7-35). All (100%) the patients were satisfied with their outcome (9 very satisfied, 7 satisfied), and their mean subjective shoulder value was 73% (range, 10%-100%). However, 2 patients complained of hardware-related symptoms, and 1 patient had return of preoperative symptoms after an interim 2 years of pain relief. CONCLUSION: The use of mirrored 3D-printed clavicles combined with virtual surgical planning and patient-specific 3D guides provides a reliable technique for restoring native anatomy when performing corrective osteotomies for clavicle malunion or internal fixation for clavicle nonunion, with a high rate of satisfactory clinical and radiographic outcomes.

Trends in early gestation stillbirths and neonatal deaths in New South Wales, Australia 2002-2019.

BACKGROUND: Little research has focused on understanding trends in early gestation (20-27 weeks) stillbirths and neonatal deaths. AIMS: To examine trends in early gestation stillbirths and neonatal deaths in New South Wales (NSW), Australia. MATERIALS AND METHODS: Population-based cohort study of all births ≥20 weeks gestation among female NSW residents during 2002 to 2019, induced pregnancy terminations excluded. Stillbirth rates by gestational age and birth year were calculated per 1000 fetuses-at-risk (FAR). Neonatal death rates by gestational age and birth year were calculated per 1000 live births. Linear regression was used to examine trends in stillbirth and neonatal death rates among all, singleton and twin births. RESULTS: Declining trends in early gestation stillbirth and neonatal death rates were found. Stillbirth rates decreased from 1.9 and 0.9/1000 FAR in 2002 to 1.6 and 0.7 in 2019 for 20-23 and 24-27 week groups, respectively. Neonatal rates decreased from 940 and 315/1000 live births in 2002 to 925 and 189 in 2019 for the 20-23 and 24-27 week groups, respectively. Among singleton births, declining trends in stillbirth and neonatal death rates across all age groups were observed, except for 37-38 week stillbirths. No trends in twin stillbirth rates were found across gestational age groups, although a decreasing trend was observed for 20-23 week twin neonatal deaths. CONCLUSIONS: Trends in early gestation stillbirth and neonatal deaths have declined in recent decades in NSW but further efforts are needed to reduce both early and late gestation stillbirth rates among twin births.

Craniomaxillofacial Trauma: The Past, Present and the Future.

Reconstruction of facial trauma has seen a significant evolutionary leap in the last 100 years. The current surgical management of facial fractures was made possible by the efforts and creativity of pioneer surgeons, advances in anatomic understanding, and the continued development of biomaterials and imaging technologies. Virtual surgical planning (VSP) and 3-dimensional printing (3DP) are being incorporated into the management of acute facial trauma. The integration of this technology at the point of care is rapidly expanding globally. This article reviews the history of the management of craniomaxillofacial trauma, current practices, and future directions. The use of VSP and 3DP in facial trauma care is highlighted with a description of EPPOCRATIS, a rapid point-of-care process incorporating VSP and 3DP at the trauma center.

A Radiologist's Guide to the 2021 WHO Central Nervous System Tumor Classification: Part I-Key Concepts and the Spectrum of Diffuse Gliomas.

The fifth edition of the World Health Organization (WHO) classification of tumors of the central nervous system, published in 2021, contains substantial updates in the classification of tumor types. Many of these changes are relevant to radiologists, including "big picture" changes to tumor diagnosis methods, nomenclature, and grading, which apply broadly to many or all central nervous system tumor types, as well as the addition, elimination, and renaming of multiple specific tumor types. Radiologists are integral in interpreting brain tumor imaging studies and have a considerable impact on patient care. Thus, radiologists must be aware of pertinent changes in the field. Staying updated with the most current guidelines allows radiologists to be informed and effective at multidisciplinary tumor boards and in interactions with colleagues in neuro-oncology, neurosurgery, radiation oncology, and neuropathology. This review represents the first of a two-installment review series on the most recent changes to the WHO brain tumor classification system. This first installment focuses on the changes to the classification of adult and pediatric gliomas of greatest relevance for radiologists.

Accuracy and Precision of the Computed Tomographic Angiography Perforator Localization Technique for Virtual Surgical Planning of Composite Osteocutaneous Fibular Free Flaps in Head and Neck Reconstruction.

BACKGROUND: Virtual surgical planning (VSP), computer aided design/computer aided modeling, and 3-dimensional printing technology have been shown to improve surgical accuracy and efficiency in head and neck reconstruction. However, persisting criticism of the technology is that it does not adequately address the soft tissue-related aspects of reconstructive surgery. Prior publication on the computed tomographic angiography (CTA) perforator localization technique has demonstrated how soft tissue planning can be incorporated directly into existing VSP workflows. PURPOSE: The aim of this study is to prospectively assess the accuracy, precision, negative predictive value (NPV), and positive predictive value (PPV) of the CTA perforator localization technique for VSP of osteocutaneous fibular free flaps. MATERIALS AND METHODS: A prospective observational study in a consecutive cohort of subjects undergoing VSP of osteocutaneous fibular free flaps at Mayo Clinic between 2018 and 2020 was completed. All cutaneous perforators from the peroneal system of the selected donor leg were identified preoperatively through a previously reported CTA tracing method and registered into the VSP. Perforators were classified as primary or secondary based on whether the perforators were targeted for use in the final reconstructive plan. Perforator measurements obtained from the VSP were cross-referenced with intraoperatively obtained measurements of actual perforator locations to calculate accuracy, precision, NPV, PPV, sensitivity, and specificity of the CTA localization technique. RESULTS: Sixty consecutive subjects were enrolled in the study. A total of 141 perforators were identified preoperatively on CTA and 145 perforators were identified on operative exposure. One perforator identified on preoperative CTA was not identified on surgical exposure (false positive perforator). Six perforators were identified on operative exposure alone without recognition on preoperative CTA (false negative perforators). The accuracy of CTA perforator identification was 96.52%. Median precision of perforator localization was 0.3 cm (standard deviation 0.40) between CTA and operatively identified locations. PPV of the technique was 99.29% and NPV was 90.00%. CONCLUSION: The CTA localization technique for identifying and incorporating cutaneous perforator locations into VSP of osteocutaneous fibular free flaps is a reliable, accurate, and precise technique to employ in the modern paradigm of guided surgery for head and neck reconstruction.

The health and educational costs of preterm birth to 18 years of age in Australia.

BACKGROUND: Preterm birth is the greatest cause of death up to five years of age and an important contributor to lifelong disability. There is increasing evidence that a meaningful proportion of early births may be prevented, but widespread introduction of effective preventive strategies will require financial support. AIMS: This study estimated the economic cost to the Australian government of preterm birth, up to 18 years of age. MATERIALS AND METHODS: A decision-analytic model was developed to estimate the costs of preterm birth in Australia for a hypothetical cohort of 314 814 children, the number of live births in 2016. Costs to Australia's eight jurisdictions included medical expenditures and additional costs to educational services. RESULTS: The total cost of preterm birth to the Australian government associated with the annual cohort was estimated at $1.413 billion (95% CI 1047-1781). Two-thirds of the costs were borne by healthcare services during the newborn period and one-quarter of the costs by educational services providing special assistance. For each child, the costs were highest for those born at the earliest survivable gestational age, but the larger numbers of children born at later gestational ages contributed heavily to the overall economic burden. CONCLUSION: Preterm birth leaves many people with lifelong disabilities and generates a significant economic burden to society. The costs extend beyond those to the healthcare system and include additional educational needs. Assessments of economic costs should inform economic evaluations of interventions aimed at the prevention or treatment of preterm birth.

Dysregulation of Oxygen Sensing/Response Pathways in Pregnancies Complicated by Idiopathic Intrauterine Growth Restriction and Early-Onset Preeclampsia.

Preeclampsia (PE) and intrauterine growth restriction (IUGR) are the leading causes of maternal and fetal morbidity/mortality. The central deficit in both conditions is impaired placentation due to poor trophoblast invasion, resulting in a hypoxic milieu in which oxidative stress contributes to the pathology. We examine the factors driving the hypoxic response in severely preterm PE (n = 19) and IUGR (n = 16) placentae compared to the spontaneous preterm (SPT) controls (n = 13) using immunoblotting, RT-PCR, immunohistochemistry, proximity ligation assays, and Co-IP. Both hypoxia-inducible factor (HIF)-1α and HIF-2α are increased at the protein level and functional in pathological placentae, as target genes prolyl hydroxylase domain (PHD)2, PHD3, and soluble fms-like tyrosine kinase-1 (sFlt-1) are increased. Accumulation of HIF-α-subunits occurs in the presence of accessory molecules required for their degradation (PHD1, PHD2, and PHD3 and the E3 ligase von Hippel-Lindau (VHL)), which were equally expressed or elevated in the placental lysates of PE and IUGR. However, complex formation between VHL and HIF-α-subunits is defective. This is associated with enhanced VHL/DJ1 complex formation in both PE and IUGR. In conclusion, we establish a significant mechanism driving the maladaptive responses to hypoxia in the placentae from severe PE and IUGR, which is central to the pathogenesis of both diseases.

A Single-Institution Experience in Percutaneous Image-Guided Cryoablation of Lymph Node Metastases.

OBJECTIVE. The purpose of this study was to assess the feasibility, safety, and efficacy of percutaneous cryoablation for the treatment of lymph node metastases. MATERIALS AND METHODS. In this single-institution retrospective study 55 patients were identified who underwent CT-guided cryoablation of metastatic lymph nodes between November 2006 and September 2019. Patient demographics, disease characteristics, and procedural details were recorded. The primary endpoints were technical success and major complications. The secondary endpoints were time to local and time to distant progression. Complications were graded according to the Society of Interventional Radiology consensus guidelines. RESULTS. The study sample comprised 55 patients (42 men, 13 women; mean age 64 ± 12 years) who underwent 61 cryoablation procedures to treat 65 lymph node metastases. Targeted nodes measured 1.7 ± 1.2 cm in mean short-axis diameter. Technical success was achieved in 60 of 61 cryoablation procedures (98%). Adjunctive maneuvers performed to protect adjacent structures included hydrodissection (n = 40), ureteral stenting (n = 3), and neural monitoring (n = 3). There were two Society of Interventional Radiology major complications (3%): pneumothorax (n = 1) and bleeding (n = 1). Local tumor control was achieved in treatment of 53 of 65 (82%) nodal metastases within a median of 25 months (range, 1-121 months) of follow-up. Local progression occurred in 12 of 65 cases (18%); the median time to recurrence was 11 months. CONCLUSION. Percutaneous cryoablation of nodal metastases is feasible and safe. Further investigation is warranted to assess the long-term efficacy of this technique and to define its role in oncologic care.

Rates of neonatal morbidity by maternal region of birth and gestational age in New South Wales, Australia 2003-2016.

INTRODUCTION: Research suggests that neonatal morbidity differs by maternal region of birth at different gestational ages. This study aimed to determine the overall and gestation-specific risk of neonatal morbidity by maternal region of birth, after adjustment for maternal, infant and birth characteristics, for women giving birth in New South Wales, Australia, from 2003 to 2016. MATERIAL AND METHODS: The study utilized a retrospective cohort study design using linked births, hospital and deaths data. Modified Poisson regression was used to determine risk with 95% confidence intervals (95% CI) of neonatal morbidity by maternal region of birth, overall and at each gestational age, compared with Australian or New Zealand-born women giving birth at 39 weeks. RESULTS: There were 1 074 930 live singleton births ≥32 weeks' gestation that met the study inclusion criteria, and 44 394 of these were classified as morbid, giving a neonatal morbidity rate of 4.13 per 100 live births. The gestational age-specific neonatal morbidity rate declined from 32 weeks' gestation, reaching a minimum at 39 weeks in all maternal regions of birth. The unadjusted neonatal morbidity rate was highest in South Asian-born women at most gestations. Adjusted rates of neonatal morbidity between 32 and 44 weeks were significantly lower for babies born to East (adjusted relative risk [aRR] 0.65, 95% CI 0.62-0.68), South-east (aRR 0.76, 95% CI 0.73-0.79) and West Asian-born (aRR 0.93, 95% CI 0.88-0.98) mothers, and higher for babies of Oceanian-born (aRR 1.11, 95% CI 1.04-1.18) mothers, compared with Australian or New Zealand-born mothers. Babies of African, Oceanian, South Asian and West Asian-born women had a lower adjusted risk of neonatal morbidity than Australian or New Zealand-born women until 37 or 38 weeks' gestation, and thereafter an equal or higher risk in the term and post-term periods. CONCLUSIONS: Maternal region of birth is an independent risk factor for neonatal morbidity in New South Wales.

Paradoxical Temporal Enlargement: An Expansion of Superficial Temporal Fat Pad Following Interfacial Technique for Pterional Craniotomy.

OBJECTIVE: Contour irregularities in the temporal region have been reported previously after procedures involving temporal dissection. In this study, we report paradoxical temporal enlargement (PTE) following interfascial pterional craniotomy. METHODS: A retrospective review of patients who underwent a unilateral transcranial procedure with frontotemporal approach at our institution between September 2013 and December 2017 was performed. Patients with a previous craniotomy or bilateral craniotomy were excluded. Radiological imaging series including computed tomography and magnetic resonance imaging were utilized to calculate temporal soft tissue volumes both preoperatively and postoperatively by using advanced software technology. Relative soft tissue volume differences between the operative side and the contralateral side were calculated at different time-points including preoperative, 3-months follow-up (3M), 12-months (12M) follow-up, and the last follow-up (LFU, over 1-year). RESULTS: Forty-three patients were included. Mean age was 52.7 ± 4.5 years. Mean follow-up was 27.9 ± 15.8 months. Significant changes of temporal fat pad relative-volume difference were observed between the preoperative and the corresponding 3M (t [82] = -2.8865, P = 0.0050); 12M (t [77] = -4.4321, P < 0.0001), and LFU (t [74] = -4.9862, P < 0.0001) postoperative time points. No significant change of the temporalis muscle was observed between the preoperative and the corresponding 3M (P = 0.3629), 12M (P = 0.1553), or LFU (P = 0.0715). Soft tissue volume showed a significant increase on the operative side between the preoperative and the corresponding LFU (t [74] = -2.5866, P =  0.0117). CONCLUSIONS: Paradoxical temporal enlargement with more than 10% volumetric change was observed in 24% of the patients at their LFU (>1-year). This change was not due to temporalis muscle changes. Paradoxical temporal enlargement was due to hypertrophy of the superficial temporal fat pad. Before surgical correction of postoperative temporal contour changes, it is important to obtain imaging and characterize the etiology of the deformity.

Three-Dimensional-Printed Liver Model Helps Learners Identify Hepatic Subsegments: A Randomized-Controlled Cross-Over Trial.

INTRODUCTION: The purpose of this study was to find out whether 3-dimensional (3D)-printed models improved the learners' ability to identify liver segments. METHODS: A total of 116 physicians from 3 disciplines were tested in a cross-over trial at baseline and after teaching with 3D models and 2-dimensional (2D) images. Adjusted multilevel-mixed models were used to compare scores at baseline and after 3D and 2D. RESULTS: Accuracy in identifying hepatic segments was higher with 3D first than 2D (77% vs 69%; P = 0.05) and not significantly improved by a combination of 3D and 2D. Increased confidence in segment identification was highest in trainees after 3D (P = 0.04). DISCUSSION: 3D-printed models facilitate learning hepatic segmental anatomy.

International Policy Frameworks for Consent in Minimal-risk Pragmatic Trials.

There is intense debate around the use of altered and waived consent for pragmatic trials. Those in favor argue that traditional consent compromises the internal and external validity of these trials. Those against, warn that the resultant loss of autonomy compromises respect for persons and could undermine trust in the research enterprise.This article examines whether international ethical guidelines and the policy frameworks in three countries-the United States, England, and Australia-permit altered and waived consent for minimal-risk pragmatic trials conducted outside the emergency setting. Provisions for both are clearly articulated in U.S. regulations, but many countries do not have equivalent frameworks. Investigators should not assume that all consent models permitted in the United States are legal in their jurisdictions, even if they are deemed ethically defensible.The authors summarize ethical and regulatory considerations and present a framework for investigators contemplating trials with altered or waived consent.