Evaluation of mediastinal lymph node segmentation of heterogeneous CT data with full and weak supervision.

Accurate lymph node size estimation is critical for staging cancer patients, initial therapeutic management, and assessing response to therapy. Current standard practice for quantifying lymph node size is based on a variety of criteria that use uni-directional or bi-directional measurements. Segmentation in 3D can provide more accurate evaluations of the lymph node size. Fully convolutional neural networks (FCNs) have achieved state-of-the-art results in segmentation for numerous medical imaging applications, including lymph node segmentation. Adoption of deep learning segmentation models in clinical trials often faces numerous challenges. These include lack of pixel-level ground truth annotations for training, generalizability of the models on unseen test domains due to the heterogeneity of test cases and variation of imaging parameters. In this paper, we studied and evaluated the performance of lymph node segmentation models on a dataset that was completely independent of the one used to create the models. We analyzed the generalizability of the models in the face of a heterogeneous dataset and assessed the potential effects of different disease conditions and imaging parameters. Furthermore, we systematically compared fully-supervised and weakly-supervised methods in this context. We evaluated the proposed methods using an independent dataset comprising 806 mediastinal lymph nodes from 540 unique patients. The results show that performance achieved on the independent test set is comparable to that on the training set. Furthermore, neither the underlying disease nor the heterogeneous imaging parameters impacted the performance of the models. Finally, the results indicate that our weakly-supervised method attains 90%- 91% of the performance achieved by the fully supervised training.

Cancer Clinical Trials: What Every Radiologist Wants to Know but Is Afraid to Ask.

OBJECTIVE. The purpose of this article is to provide radiologists with a guide to the fundamental principles of oncology clinical trials. The review summarizes the evolution and structure of modern clinical trials with an emphasis on the relevance of clinical trials in the field of oncologic imaging. CONCLUSION. Understanding the structure and clinical relevance of modern clinical trials is beneficial for radiologists in the field of oncologic imaging.

Overview of imaging findings associated with systemic therapies in advanced epithelial ovarian cancer.

PURPOSE: To provide an overview for radiologists of the systemic agents used in the treatment of advanced epithelial ovarian cancer (EOC) and their associated toxicities. RESULTS: EOC is a common gynecological malignancy, with the majority of patients presenting with advanced stage disease at the time of diagnosis. Although primary cytoreductive surgery and chemotherapy are the principal treatments for EOC, recurrence rates of disease remain high. As several molecular targeted therapies have been developed in the last decade, various novel agents have shown efficacy in the treatment of advanced EOC. Advanced EOC will be discussed by outlining the relevant radiological features of toxicities. CONCLUSION: Knowledge of the systemic therapies utilized in the treatment of advanced EOC and their associated radiological features is critical in diagnostic image interpretation.

A Radiologist's Guide to the Changing Treatment Paradigm of Advanced Non-Small Cell Lung Cancer: The ASCO 2018 Molecular Testing Guidelines and Targeted Therapies.

OBJECTIVE. The purpose of this article is to provide an imaging-based guide of the modern genomic classifications and targeted therapies for advanced non-small cell lung cancer (NSCLC) with an emphasis on the relevance of the 2018 American Society of Clinical Oncology molecular testing guidelines for radiologists. CONCLUSION. Knowledge of the radiologic relevance of lung cancer driver mutations and modern targeted agents is essential for imaging interpretation of advanced NSCLC in the modern age of precision medicine.

Atypical Response Patterns in Patients Treated With Nivolumab.

OBJECTIVE. The purpose of this study is to assess the frequency of atypical response patterns in oncology patients treated with the programmed cell death protein-1 inhibitor nivolumab. MATERIALS AND METHODS. This retrospective study included 254 patients treated with nivolumab alone or in combination, from January 2013 through August 2017. A blinded reader prospectively assessed treatment response. Among 166 patients (65%) who experienced a clinical benefit (defined as stable disease, partial response, or complete response as the best response), four response patterns were identified: pattern 1 is a decrease or less than 20% increase in the sum of the longest dimension (SLD) without a return to below the nadir, pattern 2 is a 10-19% increase in SLD with a return to below the nadir, pattern 3 is a 20% or greater increase in SLD with a return to below the nadir (classic pseudoprogression), and pattern 4 is the development of new lesions with a decrease in SLD lasting through at least two consecutive scans. Patterns 2, 3, and 4 were defined as atypical response patterns. RESULTS. Of 166 patients who experienced a clinical benefit, pattern 1 was seen in 133 (80%), pattern 2 was seen in 15 (9%), pattern 3 was seen in two (1%), and pattern 4 was seen in 16 (10%) patients. Thus, atypical response patterns were seen in 33 (20%) patients who experienced a clinical benefit, including 25 of 91 (27%) taking nivolumab and ipilimumab combined, six of 46 (13%) taking nivolumab alone, and two of 29 (7%) taking a combination of nivolumab and another chemotherapeutic agent (p = 0.02). CONCLUSION. Although classic pseudoprogression was rare, an atypical response was seen in 20% of patients who experienced a clinical benefit, and a delayed response up to 24 months of therapy may be seen. Radiologists should be aware of these atypical patterns to avoid errors in response assessment.

An imaging-based review of systemic therapies and associated toxicities in metastatic pancreatic cancer as per the 2018 ASCO guidelines: what every radiologist should know.

OBJECTIVE: To provide an overview of what radiologists should know about systemic agents utilized in the modern treatment of metastatic pancreatic cancer and their associated toxicities. RESULTS: The clinical landscape of metastatic pancreatic cancer has significantly evolved in recent years, with the advent of new first- and second-line systemic therapies. As these systemic treatment options continue to expand, knowledge of their clinically relevant features is becoming critical for radiologists. While the issues of surgical resectability and tumor response evaluation of advanced stages of pancreatic cancer have been thoroughly discussed in the radiology literature, the diagnostic importance of systemic therapies has tended to be less well appreciated. In this review, we provide a primer for radiologists outlining the radiologically pertinent features of modern systemic therapies used in the treatment of metastatic pancreatic ductal adenocarcinoma. These systemic agents are discussed from the standpoint of the newly updated 2018 ( https://doi.org/10.1007/s00261-019-01954-z ) guidelines for the treatment of metastatic pancreatic cancer from the American Society of Clinical Oncology (ASCO). Understanding the radiology relevance of these modern therapeutic agents is critical, especially with regard to treatment response and toxicity assessment. CONCLUSION: Knowledge of the modern systemic therapies utilized in the treatment of metastatic pancreatic cancer and their associated toxicity profiles is critical in diagnostic imaging interpretation.

Overview of systemic treatment in recurrent and advanced cervical cancer: a primer for radiologists.

Imaging has a central role in surveillance of cervical cancer, guiding decision on when to initiate treatment for recurrent disease and to guide management in advanced cervical cancer. Due to the increased availability of pelvic radiation therapy, the rate of atypical presentation of recurrent disease has increased. Simultaneously, the array of systemic therapies now available for advanced cervical cancer has considerably expanded in the last few years, with therapies now available in mid and low-income countries. While pelvic recurrences are amenable of loco-regional treatment, recurrent disease may present with metastases to the thoracoabdominal organs, lymph nodes, bones, skin and brain, for which systemic treatment represent the standard of care. Besides combined chemotherapy regimens, alternative chemotherapies, biosimilars and immune checkpoint inhibitors are now available, each associated with a definite pattern of response and toxicity. In this review, after describing the typical and atypical presentations of recurrent and advanced cervical carcinoma on cross-sectional imaging, we will discuss systemic treatment for recurrent or advanced disease and their associated radiographic sequelae, in light of the newly available therapies.

Review of targeted therapy in chronic lymphocytic leukemia: what a radiologist needs to know about CT interpretation.

The last 5 years have been marked by profound innovation in the targeted treatment of chronic lymphocytic leukemia (CLL) and indolent lymphomas. Using CLL as a case study, we present a timeline and overview of the current treatment landscape for the radiologist, including an overview of clinical and radiological features of CLL, discussion of the targeted agents themselves, and the role of imaging in response and toxicity assessment. The goal is to familiarize the radiologist with multiple Food and Drug Administration (FDA)-approved targeted agents used in this setting and associated adverse events which are commonly observed in this patient population.

Immune-related tumour response assessment criteria: a comprehensive review.

Growing emphasis on precision medicine in oncology has led to increasing use of targeted therapies that encompass a spectrum of drug classes including angiogenesis inhibitors, immune modulators, signal transduction inhibitors, DNA damage modulators, hormonal agents etc. Immune therapeutic drugs constitute a unique group among the novel therapeutic agents that are transforming cancer treatment, and their use is rising. The imaging manifestations in patients on immune therapies appear to be distinct from those typically seen with conventional cytotoxic therapies. Patients on immune therapies may demonstrate a delayed response, transient tumour enlargement followed by shrinkage, stable size, or initial appearance of new lesions followed by stability or response. These newer patterns of response to treatment have rendered conventional criteria such as World Health Organization and response evaluation criteria in solid tumours suboptimal in monitoring changes in tumour burden. As a consequence, newer imaging response criteria such as immune-related response evaluation criteria in solid tumours and immune-related response criteria are being implemented in many trials to effectively monitor patients on immune therapies. In this review, we discuss the traditional and new imaging response criteria for evaluation of solid tumours, review the outcomes of various articles which compared traditional criteria with the new immune-related criteria and discuss pseudo-progression and immune-related adverse events.

Volumetric MRI Analysis of Plexiform Neurofibromas in Neurofibromatosis Type 1: Comparison of Two Methods.

OBJECTIVES: Plexiform neurofibromas (PNs) are complex, histologically benign peripheral nerve sheath tumors that are challenging to measure by simple line measurements. Computer-aided volumetric segmentation of PN has become the recommended method to assess response in clinical trials directed at PN. Different methods for volumetric analysis of PN have been developed. The goal of this study is to test the level of agreement in volume measurements and in interval changes using two separate methods of volumetric magnetic resonance imaging analysis. METHODS: Three independent volume measurements were performed on 15 PN imaged at three time-points using 3DQI software at Massachusetts General Hospital (MGH) and National Cancer Institute (NCI) and MEDx software at NCI. RESULTS: Median volume differences at each time-point comparing MGH-3DQI and NCI-3DQI were -0.5, -4.2, and -19.9 mL; comparing NCI-3DQI and NCI-MEDx were -21.0, -47.0, and -21.0 mL; comparing MGH-3DQI and NCI-MEDx were -10.0, -70.3, and -29.9 mL. Median differences in percentage change over time comparing MGH-3DQI and NCI-3DQI were -1.7, 1.1, and -1.0%; comparing NCI-3DQI and NCI-MEDx were -2.3, 3.3, and -1.1%; comparing MGH-3DQI and NCI-MEDx were -0.4, 2.0, and -1.5%. Volume differences were <20% of the mean of the two measurements in 117 of 135 comparisons (86.7%). Difference in interval change was <20% in 120 of the 135 comparisons (88.9%), while disease status classification was concordant in 115 of 135 comparisons (85.2%). CONCLUSIONS: The volumes, interval changes, and progression status classifications were in good agreement. The comparison of two volumetric analysis methods suggests no systematic differences in tumor assessment. A prospective comparison of the two methods is planned.

Occurrence and significance of morphologic changes in patients with metastatic triple negative breast cancer treated with Cabozantinib.

OBJECTIVE: To compare performance of RECIST1.1 and Choi criteria in assessment of patients with metastatic triple-negative breast cancer treated with cabozantinib. METHODS: Thirty patients with metastatic triple-negative breast cancer enrolled in phase 2 clinical trial received cabozantinib. Clinical benefit rates assessed by prospectively determined RECIST1.1 and retrospectively assessed Choi criteria were compared. RESULTS: Decreased tumor density (≥15%) at first follow-up was seen in 22/30(73%) patients. CBR was 40% (95%CI:23-59%) by RECIST1.1, and 73% (95%CI:54-88%) by Choi (NPV=100%, 95%CI:63-100%; PPV=55%, 95%CI:32-76%). CONCLUSIONS: Morphologic changes are seen in the majority of patients treated with cabozantinib, making Choi criteria valuable in response assessment.

Patterns and Prognostic Importance of Hepatic Involvement in Patients with Serous Ovarian Cancer: A Single-Institution Experience with 244 Patients.

Purpose To evaluate the frequency, patterns, and prognostic importance of metastatic hepatic involvement in serous ovarian cancer. Materials and Methods This institutional review board-approved retrospective study, with waived informed consent, included 244 patients with pathologically proven serous ovarian cancer (mean age ± standard deviation, 59 years ± 10.7; range 19-93 years). Electronic medical records and all available imaging studies over a median follow-up of 44 months (interquartile range [IQR], 27-70) were reviewed to identify the frequency of liver parenchymal invasion (LPI) from perihepatic peritoneal metastasis and hematogenous liver metastases. The associations and prognostic importance of LPI and hematogenous metastases were studied by using univariate and multivariate Cox proportional analysis. Results Eighty-four of 244 patients (34%) developed perihepatic metastases, of whom 55 (23%) developed LPI after median of 43 months (IQR, 25-63). Hematogenous hepatic metastases developed in 38 of 244 patients (16%) after median of 42 months (IQR, 26-64). At multivariate analysis, age (P = .008; hazard ratio [HR]: 1.03; 95% confidence interval [CI]: 1.009, 1.07) and suboptimal cytoreduction (P = .03; HR, 2.13; 95% CI: 1.12, 4.07) were associated with LPI. Increasing age (P = .01; HR, 1.04; 95% CI: 1.008, 1.08), high-grade tumor (P = .01; HR, 6.75; 95% CI: 1.44, 120.5), and advanced stage (P = .03; HR, 3.16; 95% CI: 1.94, 4.56) were associated with hematogenous metastases. Overall survival with and without LPI was similar (median, 80 months; IQR, 50-not reached vs 123 months; IQR, 49-279; P = .6). Hematogenous metastases were associated with significantly shorter survival at univariate (median 63 months, IQR 43-139 vs 145 months, IQR 50-not reached; P = .006) and multivariate analyses (P = .03; HR, 1.88; 95% CI: 1.14, 3.28). Conclusion Differentiating hematogenous metastases and LPI is important for radiologists; hematogenous metastases are associated with shorter survival, while LPI does not adversely affect survival and prognostically behaves like peritoneal disease. © RSNA, 2016.

Ovarian Cancer: An Evidence-Based, Easy-to-Use Prediction Rule to Optimize the Use of Follow-up Chest CT.

PURPOSE: To create and validate an evidence-based prediction rule to optimize use of follow-up chest CT for ovarian cancer. METHODS: In this Institutional Review Board-approved retrospective study performed at two academic medical centers, electronic medical records from January through December 2013 at center 1 (USA) and January 2012 through December 2013 at center 2 (South Korea) were searched to identify consecutive chest CTs performed within 5 years of initial cytoreductive surgery in patients with pathologically proven ovarian cancer. Three separate study cohorts were created: cohort 1, 316 CTs (in 150 patients) with high-grade serous ovarian cancer (HGSC) from center 1; cohort 2, 374 CTs (81 patients) with HGSC from center 2; and cohort 3, 87 CTs (56 patients) with non-HGSC histologies from center 1. A radiologist blinded to outcome of CT, using a prediction rule that utilized previously available information, categorized each CT into "high-risk" (stage 4 at presentation and/or preexisting abdominal disease [disease below diaphragmatic dome, visualized on abdominal CT]) or "low-risk" (neither of above). A blinded radiologist then reviewed chest CTs in random order to record thoracic metastases above the diaphragmatic dome, and outcome was compared with prediction rule risk category. RESULTS: Among the three cohorts and in the total population, the prediction rule identified 94 of 316 (30%), 170 of 374 (45%), 53 of 87 (61%), and 317 of 777 (41%) CTs as "low-risk," respectively. The sensitivity, specificity, positive predictive value, negative predictive value, positive likelihood ratio, and negative likelihood ratio were as follows: cohort 1: 95%, 35%, 24%, 97%, 1.46, 0.14; cohort 2: 88%, 53%, 29%, 95%, 1.87, 0.22; cohort 3: 88%, 66%, 21%, 98%, 2.59, 0.18; total population: 91%, 47%, 26%, 96%, 1.72, 0.19. False-negative rate in the three cohorts and in total population was 3 of 94 (3%), 8 of 170 (5%), 1 of 53 (2%), and 12 of 317 (4%); however, in each of these cases there was concurrent new abdominal disease. CONCLUSIONS: The easy-to-use prediction rule helps avoid unnecessary chest CTs in patients with ovarian cancer with high sensitivity and negative predictive value, and with minimal risk of missing thoracoabdominal metastases.

Advanced High-Grade Serous Ovarian Cancer: Frequency and Timing of Thoracic Metastases and the Implications for Chest Imaging Follow-up.

PURPOSE: To study the frequency, timing, and associations of thoracic metastases in advanced (stage III and IV) high-grade serous ovarian cancer (HGSC) to help optimize the use of cross-sectional chest imaging. MATERIALS AND METHODS: This institutional review board-approved retrospective study with waived informed consent included 186 consecutive patients with pathologically proven advanced HGSC after primary cytoreduction (mean age ± standard deviation, 60 years ± 9.7) who underwent imaging at our tertiary cancer institution from January 2012 to December 2012 with at least 1 year of follow-up, unless there was thoracic metastasis or death. Electronic medical records and all available imaging studies were reviewed to record patient and tumor characteristics, frequency and timing of abdominal and thoracic metastases, and visibility of the first thoracoabdominal metastasis on abdominal images. Patient and tumor characteristics associated with thoracic metastases were studied by using univariate and multivariate Cox proportional analysis. RESULTS: After median follow-up of 57 months (interquartile range [IQR], 38-93), 175 patients (94%) developed metastatic disease; each had abdominal disease, and 76 (41%) had thoracic metastases. The first thoracoabdominal metastasis was visible on abdominal images in all 175 patients. The thoracic metastasis-free interval was longer than the abdominal disease-free interval (median, 85 months [IQR, 28-131] vs 14 months [IQR, 7-27], respectively; P < .0001). Presence of disease on abdominal images (hazard ratio, 2.56; 95% confidence interval: 1.35, 4.76) was the only factor independently associated with thoracic metastases. CONCLUSION: Thoracic metastases in advanced HGSC rarely occur before abdominal disease, and first thoracoabdominal metastases are invariably visible on abdominal images. Therefore, cross-sectional chest imaging may be deferred until development of abdominal disease, with minimal risk of missing thoracic metastases.

Image-guided ovarian mass biopsy: efficacy and safety.

PURPOSE: Image-guided needle biopsy represents a minimally invasive method for pathologic diagnosis of a mass. This study evaluates the diagnostic yield, accuracy, and safety of ovarian mass biopsy with combined core and fine-needle technique. MATERIALS AND METHODS: Medical records of all women at least 18 years of age, referred from gynecologic oncology, who underwent image-guided ovarian mass biopsy from 2001 through 2011 were reviewed. Among 27 patients, ultrasound guidance was used in 13 (48%), six transabdominal and seven transvaginal; computed tomography guidance was used in 14 (52%), nine transabdominal and five transgluteal. Biopsy indications were suspected metastasis (n = 15; 56%), suspected ovarian cancer to be treated with neoadjuvant chemotherapy (n = 10; 37%), and relative contraindication to surgery (n = 2; 7%). Mean maximum lesion dimension was 9.9 cm (range, 2-23 cm), with solid composition in nine (33%), cystic in six (22%), and mixed in 12 (44%). Biopsy pathologic findings were compared versus those of the surgical specimen or, for masses that were not resected, versus the stability of benign masses and response to chemotherapy of malignant masses on follow-up. RESULTS: All biopsies yielded a diagnosis. No biopsy-related complications were noted. Eleven patients (41%) did not undergo lesion resection and were followed for an average of 28.8 months (range, 0.3-118.4 mo). In no patient did malignancy develop during clinical follow-up after a benign biopsy diagnosis. Sensitivity and specificity for diagnosis of malignancy were 100% ± 0 (19 of 19) and 88% ± 26 (seven of eight), respectively, for cancer detection. In nine patients (33%) with final pathologic diagnosis of epithelial ovarian cancer, tumor seeding was not observed during a mean follow-up of 44.6 months (range, 1.3-110.2 mo). CONCLUSIONS: Image-guided ovarian mass core needle biopsy results in a pathologic diagnosis of benign and malignant masses with high yield, accuracy, and safety.

Magnetic resonance imaging for hypertrophic cardiomyopathy update.

OBJECTIVES: Hypertrophic cardiomyopathy (HCM) is a genetic disease of the myocardium. Although many patients remain asymptomatic, sudden cardiac death could be the first manifestation of HCM. Magnetic resonance imaging (MRI) plays an important role in the diagnosis and management of this disease. METHODS: The epidemiology, pathophysiology, and diagnosis of HCM will be briefly reviewed. This is followed by a discussion on the role of cardiac MRI, recommended protocol, typical imaging findings of HCM, and advanced MRI techniques. CONCLUSIONS: Although MRI is not intended to be a first-line tool for the assessment of HCM, MRI does provide valuable information to aid the management of patients either at risk of or diagnosed with HCM.

Inferior vena cava filters for the cerebrovascular patient.

Acute cerebrovascular disease is often complicated by deep venous thrombosis and pulmonary embolism. Many of these patients are at high risk of intracranial hemorrhage with therapeutic anticoagulation. These patients may benefit from insertion of inferior vena cava filters. Studies specifically dealing with stroke patients are lacking, but it is the authors' opinion that filters reduce the incidence of pulmonary embolism. There is little evidence to support the use of these devices prophylactically in patients who do not have venous thromboembolism. Retrievable filters are an attractive option but there are concerns about their safety; and if regularly used, a system for successful filter retrieval in all patients should be instituted. The role of concurrent anticoagulation with filters is not clear. However, we believe anticoagulation, in the absence of a contraindication, is beneficial in patients with active venous thromboembolism.

Long-term safety and effectiveness of inferior vena cava filters in patients with stroke.

PURPOSE: To assess the long-term safety and clinical effectiveness of inferior vena cava (IVC) filters in patients with stroke. METHOD AND MATERIALS: In this institutional review board-approved, Health Insurance Portability and Accountability Act-compliant retrospective study, we reviewed the clinical data of patients who had stroke and were treated with an IVC filter from 2002 to 2009. The demographics, clinical data, indications for IVC filter, procedural complications, symptomatic post-filter pulmonary embolism (PE) and deep vein thrombosis (DVT), caval occlusion and incidental, imaging-evident filter-related complications were recorded. Safety was assessed through occurrence of filter-related complications during placement and follow-up. Effectiveness was assessed through occurrence of post-filter fatal and non-fatal PE. RESULTS: During this period, 371 patients (224 male; mean age 67.5 years) with stroke received an IVC filter. The stroke was hemorrhagic in 28%, ischemic in 20%, associated with intracranial malignancy in 21% and trauma in 31%. 235 (63%) patients (PE in 159) had venous thromboembolism on imaging. The indications for IVC filter included contraindication to anticoagulation in 251 (68%), prophylaxis in 83 (22%), added protection in 22 (6%) and complication or failure of anticoagulation in 15 (4%). There was one procedural complication. During a follow-up of 1.74±2.36 years, 180 (49%) patients died, three due to post-filter PE and the remainder all due to primary disease. Symptomatic post-filter PE and DVT occurred at a frequency of 15% (54/371) and 16% (60/371), respectively. Of these, 15 (4%) had imaging-proven PE. Three (0.8%) succumbed to post-filter PE. Imaging-proven new or recurrent DVT occurred in 6% and 8%, respectively. Symptomatic caval occlusion was seen in five (5/371, 1.3%). CONCLUSION: IVC filters have an acceptable safety profile in stroke patients. In our cohort, they were effective in preventing life-threatening PE.

Segmental arterial mediolysis: clinical and imaging features at presentation and during follow-up.

PURPOSE: To review clinical and imaging features at presentation and during follow-up of patients with a suspected diagnosis of segmental arterial mediolysis (SAM). MATERIALS AND METHODS: All cases of SAM diagnosed at a single institution from 2000 to 2010 were included. Diagnosis was based on characteristic radiologic features in the absence of other plausible diagnoses. Medical records were reviewed for demographics, presenting symptoms, and laboratory and imaging findings at presentation and during follow-up. RESULTS: Fourteen patients (nine men; mean age, 53 y ± 15) were diagnosed with SAM. Initial presentation included abdominal or flank pain (n = 8) and chest pain, headache, stroke, or suprapubic fullness (n = 1 each). Two patients were asymptomatic. Inflammatory markers were negative in all cases. Imaging at presentation revealed involvement of celiac (n = 7), common hepatic (n = 3), splenic (n = 2), superior mesenteric (n = 5), renal (n = 5), and iliac (n = 2) arteries and the abdominal aorta (n = 1). Imaging demonstrated arterial dissections (n = 10), fusiform aneurysms (n = 6), arterial wall thickening (n = 2), and artery occlusion (n = 1). Clinical follow-up was available in 13 patients (median, 25 mo). Symptoms improved (n = 4), resolved (n = 3), or remained stable (n = 2), and four patients experienced new symptoms. Follow-up imaging, available in 10 patients at a median of 33 months, demonstrated new dissections, aneurysms, or arterial occlusions in five patients, including carotid artery dissection in three. Imaging findings remained stable (n = 3), improved (n = 1), or resolved (n = 1). CONCLUSIONS: SAM affects middle-aged and elderly patients. Visceral artery dissections and aneurysms are common. The disease progresses in nearly half the patients. Serial follow-up with computed tomographic angiography and/or magnetic resonance angiography may be necessary to monitor disease progression.

Stent-assisted coil embolization of an intraparenchymal renal artery aneurysm in a patient with neurofibromatosis.

True renal artery aneurysms are rare. They are generally asymptomatic, however, a few may present with hypertension, rupture, or renal dysfunction secondary to distal embolization. Indications for intervention include aneurysm of ≥ 2.0 cm in diameter, renovascular hypertension, enlarging aneurysm, associated dissection /rupture, and aneurysms in women of child-bearing age/ pregnancy. Endovascular therapy through coil embolization or stent graft exclusion is the recommended management. Coil embolization of the first and second order branch aneurysms is often associated with distal parenchymal loss and current stent graft technology prohibits use of these endoprostheses in the branch renal arteries. In this report, we describe successful stent-assisted coil embolization of an intraparenchymal aneurysm while preserving the distal parenchyma in a young woman with Neurofibromatosis type 1.