Intraprocedural Versus Initial Follow-up Minimal Ablative Margin Assessment After Colorectal Liver Metastasis Thermal Ablation: Which One Better Predicts Local Outcomes?

OBJECTIVES: The aim of this study was to investigate the prognostic value of 3-dimensional minimal ablative margin (MAM) quantified by intraprocedural versus initial follow-up computed tomography (CT) in predicting local tumor progression (LTP) after colorectal liver metastasis (CLM) thermal ablation. MATERIALS AND METHODS: This single-institution, patient-clustered, tumor-based retrospective study included patients undergoing microwave and radiofrequency ablation between 2016 and 2021. Patients without intraprocedural and initial follow-up contrast-enhanced CT, residual tumors, or with follow-up less than 1 year without LTP were excluded. Minimal ablative margin was quantified by a biomechanical deformable image registration method with segmentations of CLMs on intraprocedural preablation CT and ablation zones on intraprocedural postablation and initial follow-up CT. Prognostic value of MAM to predict LTP was tested using area under the curve and competing-risk regression model. RESULTS: A total of 68 patients (mean age ± standard deviation, 57 ± 12 years; 43 men) with 133 CLMs were included. During a median follow-up of 30.3 months, LTP rate was 17% (22/133). The median volume of ablation zone was 27 mL and 16 mL segmented on intraprocedural and initial follow-up CT, respectively ( P < 0.001), with corresponding median MAM of 4.7 mm and 0 mm, respectively ( P < 0.001). The area under the curve was higher for MAM quantified on intraprocedural CT (0.89; 95% confidence interval [CI], 0.83-0.94) compared with initial follow-up CT (0.66; 95% CI, 0.54-0.76) in predicting 1-year LTP ( P < 0.001). An MAM of 0 mm on intraprocedural CT was an independent predictor of LTP with a subdistribution hazards ratio of 11.9 (95% CI, 4.9-28.9; P < 0.001), compared with 2.4 (95% CI, 0.9-6.0; P = 0.07) on initial follow-up CT. CONCLUSIONS: Ablative margin quantified on intraprocedural CT significantly outperformed initial follow-up CT in predicting LTP and should be used for ablation endpoint assessment.

Pitfall of 18 F-PSMA PyL PET/CT Imaging of a Displaced Urinary Bladder as Recurrent Prostate Malignancy.

ABSTRACT: We herein present a potential pitfall in the setting of restaging PSMA PyL PET/CT. In this case, there is large non-PSMA-avid cystic structure in the mid pelvis, probably representing a postprostatectomy lymphocele, which was mistaken for the urinary bladder, resulting in the displaced and somewhat crescentic urinary bladder to be deemed recurrence. Subsequently, biopsy and retrospective review of images confirms displaced urinary bladder containing physiologic excreted activity.

A History and Modern Framework for Quality Improvement in Interventional Radiology.

Quality improvement (QI) initiatives have benefited patients as well as the broader practice of medicine. Large-scale QI has been facilitated by multi-institutional data registries, many of which were formed out of national or international medical society initiatives. With broad participation, QI registries have provided benefits that include but are not limited to establishing treatment guidelines, facilitating research related to uncommon procedures and conditions, and demonstrating the fiscal and clinical value of procedures for both medical providers and health systems. Because of the benefits offered by these databases, Society of Interventional Radiology (SIR) and SIR Foundation have committed to the development of an interventional radiology (IR) clinical data registry known as VIRTEX. A large IR database with participation from a multitude of practice environments has the potential to have a significant positive impact on the specialty through data-driven advances in patient safety and outcomes, clinical research, and reimbursement. This article reviews the current landscape of societal QI programs, presents a vision for a large-scale IR clinical data registry supported by SIR, and discusses the anticipated results that such a framework can produce.

A Sticky Situation: Glue Migration during Hepatic Vein Embolization.

The addition of hepatic venous embolization to portal venous embolization to achieve ipsilateral liver venous deprivation before major hepatectomy has been suggested to increase the extent of hypertrophy of the future liver remnant. The presented case discusses a hepatic vein embolization procedure complicated by the unintended migration of a glue cast used to achieve hepatic venous occlusion and subsequent management with endovascular retrieval of the glue cast from the inferior vena cava. The emerging role of hepatic venous embolization and associated complications are also discussed.

Is fluoroscopy-guided percutaneous bone biopsy of diabetic foot with suspected osteomyelitis worthwhile? A retrospective study.

BACKGROUND: Diabetic foot infection, particularly osteomyelitis, is a major risk factor of amputation in persons with diabetes. Bone biopsy with microbial examination is considered the gold standard of diagnosis of osteomyelitis, providing information about the offending pathogens as well as their antibiotics susceptibility. This allows targeting of these pathogens with narrow spectrum antibiotics, potentially reducing emergence of antimicrobial resistance. Percutaneous fluoroscopy guided bone biopsy allows accurate and safe targeting of the affected bone. METHODS: In a single tertiary medical institution and over 9 year period, we performed 170 percutaneous bone biopsies. We retrosepctively reviewed the medical record of these patients including patients' demographics, imaging and biopsy microbiology and pathollogic results. RESULTS: Microbiological cultures of 80 samples (47.1%) were positive with 53.8% of the positive culture showed monomicrobial growth and the remaining were polymicrobial. Of the positive bone samples 71.3% grew Gram-positive bacteria. Staphylococcus aureus was the most frequently isolated pathogen from positive bone cultures with almost one third showing methicillin resistence. Enterococcus species were the most frequently isolated pathogens from polymicrobial samples. Enterobacteriaceae species were the most common Gram-negative pathogens and were more common in polymicrobial samples. CONCLUSIONS: Percutaneous image-guided bone biopsy is a low-risk, minimally invasive procedure that can provide valuable information about microbial pathogens and therefore enable targeting these pathogens with narrow spectrum antibiotics.

Chronic splenic artery occlusion with gastric wall arterial ectasia, an unusual cause of massive upper gastrointestinal hemorrhage.

Life-threatening upper gastrointestinal (GI) hemorrhage can occur as a result of bleeding from a variety of arterial and venous sources. We present an unusual cause of life-threatening upper GI hemorrhage arising from ectatic gastric wall arterial branches in a 49-year-old male with previously unrecognized chronic splenic artery thrombosis. The patient developed a recurrence of bleeding despite coil embolization of an accessory left gastric artery branch supplying the gastric fundus suspected to be the site of active bleeding. The patient subsequently underwent splenectomy and surgical ligation of a bleeding gastric artery branch. This case emphasizes the importance of recognizing this unusual cause of upper GI hemorrhage for proper management and prevention of recurrence. Informed consent was obtained from the patient for publication of the case report including accompanying images.

Clinicopathological features of incidental parotid lesions.

BACKGROUND: The purpose of this study is to determine the histopathological spectrum and risk of primary malignancy of asymptomatic parotid lesions incidentally discovered on cross-sectional imaging. METHODS: Over a 10-year period, 154 patients underwent 163 ultrasound-guided parotid lesion biopsies at our institution. This retrospective chart review included 89 lesions in 87 patients with asymptomatic parotid lesions discovered on cross-sectional imaging studies performed for unrelated clinical indications. The histopathologic findings of all sampled lesions were reviewed. We evaluated the patient demographics and pathological diagnoses of sampled parotid lesions to determine the histopathological spectrum and risk of malignancy. RESULTS: The average age was 67.5 years and 92 % were males. 25 % of patients had bilateral lesions. The average size of the parotid lesions was 1.5 cm and 91 % were located in the superficial lobe. 92.1 % of lesions were benign with Warthin tumor being the most common diagnosis followed by pleomorphic adenoma. 2.3 % of lesions were primary parotid malignant neoplasms, while 5.6 % were metastatic lesions in patients with known malignancy. CONCLUSIONS: The incidence of primary parotid malignant neoplasm in asymptomatic incidentally discovered parotid lesions is low. Imaging or clinical follow-up may be considered in patients with incidental parotid lesions who prefer to avoid biopsy.

Forty-One Million RADPEER Reviews Later: What We Have Learned and Are Still Learning.

ACR RADPEER® is the leading method of radiologic peer review in the United States. The program has evolved since its inception in 2002 and was most recently updated in 2016. In 2018, a survey was sent to RADPEER participants to gauge the current state of the program and explore opportunities for continued improvement. A total of 26 questions were included, and more than 300 practices responded. In this report, the ACR RADPEER Committee authors summarize the survey results and discuss opportunities for future iterations of the RADPEER program.

Cystic Artery Hemorrhage after Cholecystostomy Catheter Exchange Treated with Transcatheter Embolization.

The pathogenesis of formation of cystic artery pseudoaneurysms is not well understood, but is thought to result from erosion of the cystic artery wall from the adjacent inflammatory process associated with acute or chronic cholecystitis. The presented case discusses an incident of hemorrhage from a cystic artery pseudoaneurysm resulting in a large perihepatic hematoma as well as hemobilia, which developed after a routine cholecystostomy catheter exchange. This was treated with transcatheter embolization using ethylene-vinyl alcohol copolymer.

CT Dose Reduction Workshop: An Active Educational Experience.

PURPOSE: Improving patient safety by minimizing CT radiation dose, while maintaining diagnostic image quality, has become an important skill in diagnostic radiology. The aim of this study was to examine the value of an educational workshop for optimizing CT protocols in an academic department, and to assess its impact on resident education. METHODS: The CT Dose Reduction Workshop met monthly for 1 year, to teach and implement dose reduction strategies. Changes were made to CT protocols through group consensus while participants kept up to date with current literature. A survey was sent to 48 radiology residents and 32 attending radiologists in the department, including both participants and nonparticipants, after completion of the workshop, to assess its utility. The survey used a 5-point Likert-type scale. Average doses for a specific CT protocol before and after the workshop were compared. RESULTS: About 80% of respondents agreed or strongly agreed that the workshop was essential. Workshop participants expressed greater confidence in their knowledge of dose reduction techniques, with a mean score of 3.74 (95% confidence interval, 3.35-4.13), compared with nonparticipants, who had a mean score of 3.00 (95% confidence interval, 2.64-3.36) (P < .01). Dose reductions were established across numerous CT protocols. For instance, the average total dose-length product in renal mass protocol CT examinations decreased by 54% (P < .0001). CONCLUSIONS: A CT dose reduction workshop increases participants' confidence in knowledge of dose reduction techniques, fosters a culture of safety and quality improvement in the department, and reduces radiation dose to patients.

The thyroid: review of imaging features and biopsy techniques with radiologic-pathologic correlation.

Knowledge of the normal and abnormal imaging appearances of the thyroid gland is essential for appropriate identification and diagnosis of thyroid lesions. Thyroid nodules are often detected incidentally at computed tomography, magnetic resonance imaging, and positron emission tomography; however, ultrasonography (US) is the most commonly used imaging modality for characterization of these nodules. US characteristics that increase the likelihood of malignancy in a thyroid nodule include microcalcifications, solid composition, and central vascularity. Nuclear scintigraphy is commonly used for evaluation of physiologic thyroid function and for identification of metabolically active and inactive nodules. When fine-needle aspiration biopsy (FNAB) of a lesion is indicated based on clinical and radiologic features, appropriate US-guided biopsy technique and careful cytologic analysis are crucial for making the diagnosis. FNAB and core biopsy are the two percutaneous techniques used to obtain a specimen, with the latter technique being indicated following nondiagnostic or indeterminate FNAB. Specimen adequacy and diagnostic accuracy vary due to several factors, including location of aspiration and biopsy technique used. The radiologist must have a basic knowledge of thyroid disease, be familiar with specimen processing, and recognize the cytologic and radiologic appearances of thyroid lesions, all of which will facilitate the management of these lesions. Online supplemental material is available for this article.

Variability in evolution and course of gunshot injuries to the neck and impact on management. A case report.

This study reports the differences in evolution and course of multiple pseudoaneurysms (PAs) and an axillary arteriovenous fistula (AVF) after penetrating vascular trauma due to shotgun injury to the head and neck. We describe the unusual case of a young man who, following penetrating shotgun injuries to the head and neck, developed multiple PAs of the common carotid, vertebral and superficial temporal arteries as well as an axillary AVF. Serial angiographic follow-up studies documented differences in time of occurrence, evolution and course of these lesions. This allowed for tailored management using endovascular (AVF, superficial temporal artery PAs) and conservative (carotid and vertebral PAs) treatment. No complication occurred and complete cure of all lesions was achieved and documented after seven months. Time of occurrence, evolution and regression of penetrating vascular injuries can differ significantly even in the same patient. Close angiographic follow-up helps not only detect a lesion with delayed occurrence, but also provides a practical basis for decision-making for optimal therapeutic management.

MRI of suspected lower extremity musculoskeletal infection in the pediatric patient: how useful is bilateral imaging?

OBJECTIVE: The purpose of this study was to determine the frequency of bilateral abnormalities in children with suspected lower extremity musculoskeletal infection and the impact of detection of contralateral abnormalities by MRI on patient management. MATERIALS AND METHODS: A retrospective review of 165 consecutive bilateral lower extremity MRI examinations performed for suspected musculoskeletal infection in pediatric patients (64% boys and 36% girls; mean age, 7.5 years; age range, 0-18 years) in 2010 at a children's hospital was performed. Imaging findings were compared with the final clinical diagnosis and management. RESULTS: The MRI examination was normal in 2% (4/165). Osteomyelitis was diagnosed in 33% (54/165) of the MRI examinations; among these examinations 20% (11/54) had both ipsilateral septic arthritis and osteomyelitis, 2% (1/54) had bilateral osteomyelitis, and 67% (111/165) of the examinations were negative for osteomyelitis. Bilateral abnormalities were detected in 20% (22/111) of patients without osteomyelitis, with 18% (4/22) presenting with bilateral signs or symptoms. Abnormalities in the contralateral extremity included myositis (18%, 4/22), stress reaction (18%, 4/22), subcutaneous edema (18%, 4/22), leukemia (14%, 3/22), reactive joint effusion (14%, 3/22), Baker cyst (5%, 1/22), and osteonecrosis (5%, 1/22). Identification of clinically unsuspected abnormalities of the contralateral extremity by MRI was not associated with alterations in medical or surgical management in children with or without osteomyelitis. CONCLUSION: Clinically unsuspected abnormalities of the asymptomatic contralateral lower extremity are common in children referred for MRI of suspected musculoskeletal infection. However, detection of these abnormalities is not associated with alterations in patient management.

Imaging features of intravesical urachal cysts in children.

BACKGROUND: Urachal cysts, part of the spectrum of congenital urachal anomalies, are typically extrinsic to the urinary bladder. OBJECTIVE: The purpose of this study is to present the salient imaging features of a pediatric series of unusual intravesical urachal cysts that protrude into the bladder lumen. MATERIALS AND METHODS: Five children with intravesical urachal cysts depicted on imaging studies were retrospectively identified during a 6-year period at a children's hospital. The clinical charts and findings on ultrasound (US) and voiding cystourethrogram (VCUG) were reviewed. RESULTS: In all five children, US revealed a thin-walled ovoid cystic structure containing anechoic fluid or echogenic debris and residing along the midline of the anterosuperior aspect of the urinary bladder protruding into the bladder lumen. Histological examination of the partial cystectomy specimen from one child revealed a cystic urachal remnant with intestinal mucosal lining and reactive lymphoid hyperplasia. The cysts in the four other children were managed conservatively without operative intervention. CONCLUSION: The purpose of this report is to expand the spectrum of urachal remnant anomalies to include these newly recognized intravesical urachal cysts, which are characterized on US by the presence of a thin-walled cyst along the midline anterosuperior aspect of the urinary bladder.