Table of Contents
Perspectives
Review Article
- Carotid Near-Occlusion: A Comprehensive Review, Part 1—Definition, Terminology, and Diagnosis
Carotid near-occlusion is distal luminal collapse of the internal carotid artery beyond a tight stenosis. Calculating percentage stenosis for carotid near-occlusion is fallacious, and near-occlusion assessment is advised before measuring for percentage stenosis. This systematic review presents what is known about carotid near-occlusion and focuses on definition, terminology, and diagnosis.
Patient Safety
- Minimizing Radiation Exposure in Evaluation of Pediatric Head Trauma: Use of Rapid MR Imaging
This study is a retrospective review of 103 pediatric patients who underwent initial head CT and subsequent follow-up rapid MR imaging between January 2010 and July 2013. Patients had minor head injuries that required imaging. There was almost perfect agreement in the ability to detect extra-axial hemorrhage on rapid MR imaging and CT (kappa = 0.84). Evaluation of hemorrhagic contusion/hemorrhage demonstrated a moderate level of agreement between MR imaging and CT (kappa = 0.61). The authors conclude that rapid MRI is an adequate imaging technique for the follow-up of pediatric patients with minor head trauma.
Methodologic Perspectives
General Contents
- Presurgical Assessment of the Sensorimotor Cortex Using Resting-State fMRI
Task-based approaches to functional localization of the motor cortex have limitations such as long scanning times and exclusion of patients with severe functional or neurologic disabilities and children. Resting-state fMRI may avoid these difficulties because patients do not perform any goal-directed tasks. Nineteen patients were prospectively evaluated by using task-based and resting-state fMRI to localize sensorimotor function. Independent component analyses were performed to generate spatial independent components reflecting functional brain networks or noise. The motor cortex was successfully and consistently identified by using resting-state fMRI. Hand, foot, and face regions were defined in a comparable fashion with task-based fMRI.
- 3D Printing of Intracranial Aneurysms Using Fused Deposition Modeling Offers Highly Accurate Replications
The authors evaluated fused deposition modeling for the production of aneurysm models replicating patient-specific anatomy using 3D rotational angiographic data from 10 patients. A hollow model with connectors for silicone tubes was fabricated by using acrylonitrile butadiene styrene, the support material was then dissolved, and the surfaces finished by using NanoSeal. The models were filled with iodinated contrast and 3D rotational angiography was performed. Reproduction of hollow aneurysm models was technically feasible in 8 of 10 cases, and a high level of anatomic accuracy was observed.
- Postoperative Imaging Findings following Sigmoid Sinus Wall Reconstruction for Pulse Synchronous Tinnitus
Transmastoid sigmoid sinus wall reconstruction (SSWR) is a surgical technique used for the treatment of pulsatile tinnitus arising from sigmoid sinus wall anomalies. In 13 patients, CT and MR imaging examinations were assessed for the characteristics of the materials used for reconstruction, the impact of these on the adjacent sigmoid sinus, and complications. The various materials used for reconstruction (NeuroAlloderm, HydroSet, bone pate) showed characteristic imaging appearances and could be consistently identified. In 5/13 patients, there was extrinsic compression of the sigmoid sinus by graft material. Dural sinus thrombosis occurred in 2 patients. Symptoms requiring postoperative imaging after SSWR include headaches, visual disturbances, and persistent or recurrent tinnitus.
- Spine Cryoablation: Pain Palliation and Local Tumor Control for Vertebral Metastases
This is a retrospective study of imaging-guided spine cryoablation that was performed on 31 vertebral metastases in 14 patients. The lesions were refractory to conventional chemoradiation therapy or analgesics and were ablated to achieve pain palliation and local tumor control. The procedures were performed with the patient under conscious sedation (13 patients) or general anesthesia in 1 case. Postcryoablation MR imaging and PET/CT imaging were available for all patients. Spinal nerve and soft-tissue thermal protection techniques were implemented in all ablations (epidural or neuroforaminal carbon dioxide or warmed 5% dextrose). There were statistically significant decreases in the median numeric pain rating scale score and analgesic usage at 1-week, 1-month, and 3-month time points. Local tumor control was achieved in 96.7% (30/31) of tumors.
