Real-time MRI-guided percutaneous sclerotherapy of low-flow head and neck lymphatic malformations in the pediatric population - a stepwise approach.

Real-time MRI-guided percutaneous sclerotherapy is a novel and evolving treatment for congenital lymphatic malformations in the head and neck. We elaborate on the specific steps necessary to perform an MRI-guided percutaneous sclerotherapy of lymphatic malformations including pre-procedure patient work-up and preparation, stepwise intraprocedural interventional techniques and post-procedure management. Based on our institutional experience, MRI-guided sclerotherapy with a doxycycline-gadolinium-based mixture as a sclerosant for lymphatic malformations of the head and neck region in children is well tolerated and effective.

Percutaneous CT-Guided Cryoablation of the Salivary Glands in a Porcine Model.

PURPOSE: To evaluate the imaging, histologic changes and safety of computed tomography (CT)-guided cryoablation of the parotid glands in a porcine model. MATERIALS AND METHODS: Unilateral CT-guided parotid gland cryoablation was performed in 5 juvenile miniature pigs. The ablated parotid glands underwent 2 cycles of 10-minute freeze and 5-minute thaw using three 17-g cryoprobes. The animals were monitored daily for complications including pain, frostbite, infection, and sialocele or fistula formation. Follow-up CT was performed at 6 weeks postcryoablation. Pathologic evaluation was performed on 2 of the ablated parotid glands. RESULTS: All cryoablations in 5 right parotid glands, with 3 sites in each gland, were technically successful. No symptoms suggestive of facial nerve damage were observed during 6-week follow-up. One pig developed an infected sialocele, which was treated with percutaneous drainage and oral antibiotic therapy. No CT evidence of sialocele or other abnormality was identified at the 6-week follow-up in all pigs. Histologic evaluation was performed on 2 of the parotid gland specimens, 1 with the treated sialocele, and 1 of the remaining pigs without sialocele. Both glands demonstrated postprocedural intraglandular lymph nodes and reactive changes without evidence of sialocele or abscess on histopathology. CONCLUSIONS: Cryoablation of parotid glands was technically feasible in a porcine model. Only 1 pig developed sialocele, which was successfully treated. Further research is warranted to determine the potential use of salivary gland cryoablation to treat patients with drooling.

Simulation-Based Training May Improve Resident Skill in Ultrasound-Guided Biopsy.

OBJECTIVE: The purpose of this study was to determine whether simulation-based training can improve resident performance in ultrasound-guided biopsy. SUBJECTS AND METHODS: Forty radiology residents from a single academic institution enrolled in the study. Each resident performed an initial biopsy on an abdominal imaging phantom using direct ultrasound guidance. Twenty of the residents underwent a 30-minute training session with the phantom device, and 20 residents received no additional training. The residents performed a repeat biopsy of the same lesion and were graded on overall procedure time, number of skin surface punctures, number of gross needle adjustments, and subjective performance as determined by a blinded grader. RESULTS: Residents who participated in the training had a statistically significant 92.3-second reduction in procedure time (68% improvement, p = 0.01), 1.1 reduction in number of skin punctures per biopsy (50% improvement, p = 0.05), 2.5 reduction in number of needle adjustments (66% improvement, p = 0.04), and an increase of 0.85 points in score on a 5-point Likert grading scale (23% improvement, p < 0.01). Residents who did not receive any additional training did not improve in any performance metric. CONCLUSION: Simulation-based training improves overall procedure time, number of skin punctures and needle adjustments, and subjective performance.

Artifacts at Cardiac CT: Physics and Solutions.

Computed tomography is vulnerable to a wide variety of artifacts, including patient- and technique-specific artifacts, some of which are unique to imaging of the heart. Motion is the most common source of artifacts and can be caused by patient, cardiac, or respiratory motion. Cardiac motion artifacts can be reduced by decreasing the heart rate and variability and the duration of data acquisition; adjusting the placement of the data window within a cardiac cycle; performing single-heartbeat scanning; and using multisegment reconstruction, motion-correction algorithms, and electrocardiographic editing. Respiratory motion artifacts can be minimized with proper breath holding and shortened scan duration. Partial volume averaging is caused by the averaging of attenuation values from all tissue contained within a voxel and can be reduced by improving the spatial resolution, using a higher x-ray energy, or displaying images with a wider window width. Beam-hardening artifacts are caused by the polyenergetic nature of the x-ray beam and can be reduced by using x-ray filtration, applying higher-energy x-rays, altering patient position, modifying contrast material protocols, and applying certain reconstruction algorithms. Metal artifacts are complex and have multiple causes, including x-ray scatter, underpenetration, motion, and attenuation values that exceed the typical dynamic range of Hounsfield units. Quantum mottle or noise is caused by insufficient penetration of tissue and can be improved by increasing the tube current or peak tube potential, reconstructing thicker sections, increasing the rotation time, using appropriate patient positioning, and applying iterative reconstruction algorithms. ©RSNA, 2016.

Ablation zones and weight-bearing bones: points of caution for the palliative interventionalist.

PURPOSE: To evaluate and classify underlying mechanisms of adverse outcomes after percutaneous computed tomography (CT)-guided cryoablation for palliation of painful musculoskeletal metastatic disease. MATERIALS AND METHODS: Data were collected for patients who underwent CT-guided percutaneous palliative cryoablation for painful musculoskeletal metastatic disease between January 2010 and December 2012. Cases with adverse outcomes or suboptimal response were identified and classified according to the Society of Interventional Radiology (SIR) classification system for complications by outcome and according to underlying mechanism of the outcome as delineated on follow-up examination. RESULTS: There were 61 patients who received ablation for painful musculoskeletal metastatic disease. Six patients with adverse outcomes were identified. Two were minor complications (A, n = 1; B, n = 1), and four were major complications (C, n = 1; D, n = 3). Four patients incurred sequelae related to damage of ancillary structures included in the ablation zone, and two patients developed complete fractures after ablation of lesions in weight-bearing bones. CONCLUSIONS: Complete cryoablation of a painful musculoskeletal metastatic lesion may lead to ancillary damage of adjacent structures or fracture in weight-bearing bones.

Palliative procedures for the interventional oncologist.

OBJECTIVE: The purpose of this article is to present our experience using multimodality interventional radiologic techniques for the treatment of cancer-related pain across a spectrum of abnormalities. CONCLUSION: Percutaneous imaging-guided thermal ablation has emerged as a safe and efficacious treatment for painful osseous metastases. The implementation of interventional thermal ablative techniques for the treatment of intractable pain secondary to malignancy can be further expanded to include transcatheter and combination procedures.

Image-Guided Percutaneous and Transarterial Therapies for Primary and Metastatic Lung Cancer.

Lung cancer is the leading cause of cancer mortality in the world. A significant proportion of patients with lung cancer are not candidates for surgery and must resort to other treatment alternatives. Rapid technological advancements in fields like interventional radiology have paved the way for valid treatment modalities like image-guided percutaneous and transarterial therapies for treatment of both primary and metastatic lung cancer. The rationale of ablative therapies relies on the fact that focused delivery of energy induces tumor destruction and pathological necrosis. Image-guided percutaneous thermal ablation therapies are established techniques in the local treatment of hepatic, renal, bone, thyroid, or uterine lesions. In the lung, the 3 main indications for lung ablation include local curative intent, a strategy to achieve a chemoholiday in oligometastatic disease, and recently, oligoprogressive disease. Transarterial therapies include a set of catheter-based treatments that involve delivering embolic and/or chemotherapeutic agents directed into the target tumor via the supplying arteries. This article provides a comprehensive review of the various techniques available and discusses their applications and associated complications in primary and metastatic lung cancer.

Bronchial Artery Chemoembolization With Radiopaque Doxorubicin Eluding Beads in Patients With Malignant Hemoptysis from Metastatic Lung Cancer.

Purpose:This pilot study was designed to assess the technical feasibility and safety of bronchial artery chemoembolization with radiopaque doxorubicin eluting beads (DEB-BACE) in patients with malignant hemoptysis from pulmonary metastasis. Materials & Methods: Four patients underwent DEB-BACE using 70-150 µm radiopaque DEB (LC Beads LUMI, Boston Scientific). Beads delivery and deposition were assessed under fluoroscopy and cone beam computed tomography (CT), respectively. Results: All 4 procedures were technically successful. Beads delivery and deposition were successfully visualized under fluoroscopy and cone beam CT guidance in all cases. Hemoptysis was resolved after embolization in all 4 patients. There were no adverse events or immediate or early complications after DEB-BACE. Two patients (50%) required repeat DEB-BACE within 1 week due to recurrent hemoptysis, and 1 patient had DEB-BACE 1.5 years later due to recurrent hemoptysis from the contralateral lung. All targeted lesions decreased in size in follow-up studies (mean 16 months, range 1-33 months). One patient died of progressive cancer disease invading the heart 1 month after DEB-BACE. Conclusions: DEB-BACE using radiopaque LC Beads LUMI loaded with doxorubicin is technically feasible and safe for controlling hemoptysis and cancer progression in patients with metastatic lung tumors. Visualization of beads delivery under fluoroscopy and deposition of beads under cone beam CT facilitate delivery of beads and embolization of bronchial arteries.

Real-time MRI-guided percutaneous sclerotherapy treatment of venous low-flow malformations in the head and neck.

Purpose This manuscript describes the technique of real-time MRI-guided sclerotherapy for low-flow venous malformations in the head and neck based on our institutional experience. Materials and methods Ethanolamine oleate is used as the sclerosant and is mixed with gadolinium for visualization during the procedure. The five procedural steps include: (I) an initial tri-plane T2-weighted sequence to visualize the lesion; (II) a T1 FSE or trueFISP sequence to assess needle placement and advancement within the lesion; (III) a tri-plane T1 FLASH sequence to monitor sclerosant injection; (IV) a T1 FSE or VIBE sequence to assess sclerosant coverage of the malformation before needle removal; (V) a post-procedural tri-plane T1 fat-saturated sequence to confirm sclerosant coverage of the lesion. Periprocedural medications typically include steroids, antibiotic prophylaxis, and non-steroidal anti-inflammatory medication. Patients are typically admitted for overnight observation. Conclusion Real-time MRI-guided sclerotherapy for low-flow venous malformations in the head and neck is effective and safe.

Eponymous cardiovascular surgeries for congenital heart diseases--imaging review and historical perspectives.

Advances in pediatric cardiology and cardiac surgical techniques over the past few decades have revolutionized the management of the patients with congenital heart disease, and many now survive into adulthood. Several eponymous surgical procedures performed for congenital heart disease have been named after eminent surgeons. In this article, we provide a short biography of the surgeons associated with these eponymous surgical procedures along with their other important scientific contributions. This is followed by a review of these surgical procedures and their most common complications. Imaging appearances of these surgical procedures along with common complications are described and illustrated, with particular emphasis on magnetic resonance imaging. The surgical procedures described in this review include Blalock-Taussig, Potts, Waterston, Glenn, Fontan, Kawashima, Norwood, Sano, Damus-Kaye-Stansel, Mustard, Senning, Jatene, LeCompte, Rastelli, Rashkind, Ross, and Waldenhausen.

Coblation for metastatic vertebral disease.

PURPOSE: Plasma-mediated radiofrequency ablation (coblation) creates a cavity for directed polymethylmethacrylate deposition through molecular dissociation, providing a safe and efficacious cementoplasty for patients with high-risk, painful vertebral body metastatic disease. The purpose of this study was to retrospectively review and report details regarding the feasibility, safety, and efficacy of coblation and cementoplasty for treating painful advanced vertebral body metastatic disease. MATERIALS AND METHODS: Fifteen patients with painful metastatic vertebral body fractures with a posterior cortical defect and/or epidural tumor extension underwent percutaneous coblation and cementoplasty. Each patient's medical record was reviewed for technical success, imaging outcome, complications, and palliative effect. RESULTS: Of the 15 cases, 14 were completed successfully. Postprocedure imaging studies demonstrated adequate cement deposition within the targeted vertebral body without cement extravasation or fracture progression during the 1-3 months follow-up period. Pain relief was achieved in all patients, and no neurological damage was reported (mean follow-up, 141.1 ± 132.5 days). CONCLUSION: Percutaneous image-guided coblation-mediated cavity creation prior to vertebroplasty allows for safe, efficacious cement deposition in patients with metastatic foci. Future studies prospectively comparing this procedure with other standard-of-care regimens are warranted.

Indexing severity of diabetic foot infection with 99mTc-WBC SPECT/CT hybrid imaging.

OBJECTIVE: Management of diabetic foot infection (DFI) has been hampered by limited means of accurately classifying disease severity. New hybrid nuclear/computed tomography (CT) imaging techniques elucidate a combination of wound infection parameters not previously evaluated as outcome prognosticators. Our aim is to determine if a novel standardized hybrid image-based scoring system, Composite Severity Index (CSI), has prognostic value in DFI. RESEARCH DESIGN AND METHODS: Masked retrospective (99m)Tc-white blood cell (WBC) single photon emission CT (SPECT)/CT image interpretation and independent chart review of 77 patients (101 feet) suspected of DFI-associated osteomyelitis at a large municipal hospital between January 2007 and July 2009. CSI scores were correlated with probability of favorable outcome (no subsequent amputation/readmission after therapeutic intervention) during median 342-day follow-up. RESULTS: CSI ranged from 0-13. Receiver operating characteristic accuracy for predicting favorable outcome was 0.79 (optimal cutoff CSI, ≤2; odds ratio of therapeutic failure for CSI >2, 15.1 [95% CI 4.4-51.5]). CSI of 0 had a 92% chance of favorable outcome, which fell progressively to 25% as indices rose to ≥7. Image-based osteomyelitis versus no osteomyelitis assessment was less accurate than CSI at predicting outcome (P = 0.016). In patients with intermediate severity (CSI 3-6), treatment failure decreased from 68 to 36% when antibiotic duration was extended to ≥42 days (P = 0.026). CONCLUSIONS: (99m)Tc-WBC SPECT/CT hybrid image-derived wound infection parameters incorporated into a standardized scoring system, CSI, has prognostic value in DFI.