Design Considerations to Facilitate Clinical Radiological Evaluation of Implantable Biomedical Structures.

Clinical effectiveness of implantable medical devices would be improved with in situ monitoring to ensure device positioning, determine subsequent damage, measure biodegradation, and follow healing. While standard clinical imaging protocols are appropriate for diagnosing disease and injury, these protocols have not been vetted for imaging devices. This study investigated how radiologists use clinical imaging to detect the location and integrity of implanted devices and whether embedding nanoparticle contrast agents into devices can improve assessment. To mimic the variety of devices available, phantoms from hydrophobic polymer films and hydrophilic gels were constructed, with and without computed tomography (CT)-visible TaOx and magnetic resonance imaging (MRI)-visible Fe3O4 nanoparticles. Some phantoms were purposely damaged by nick or transection. Phantoms were implanted in vitro into tissue and imaged with clinical CT, MRI, and ultrasound. In a blinded study, radiologists independently evaluated whether phantoms were present, assessed the type, and diagnosed whether phantoms were damaged or intact. Radiologists identified the location of phantoms 80% of the time. However, without incorporated nanoparticles, radiologists correctly assessed damage in only 54% of cases. With an incorporated imaging agent, the percentage jumped to 86%. The imaging technique which was most useful to radiologists varied with the properties of phantoms. With benefits and drawbacks to all three imaging modalities, future implanted devices should be engineered for visibility in the modality which best fits the treated tissue, the implanted device's physical location, and the type of required information. Imaging protocols should also be tailored to best exploit the properties of the imaging agents.

Prevalence of and factors associated with posterior tibial tendon pathology on sonographic assessment.

OBJECTIVE: To assess the frequency of and factors associated with supramalleolar posterior tibial tendon (PTT) pathology that often may be missed on sonography because of the limited field of view of ultrasound. DESIGN: Retrospective cross-sectional study. SETTING: Large academic center. PATIENTS: Patients with medial ankle pain and tenderness and with normal radiographs who presented for sonographic assessment (n = 217). METHODS: Two experienced musculoskeletal radiologists interpreted the studies by consensus. MAIN OUTCOME MEASUREMENT: PTT pathology. RESULTS: Of the 217 patients, 33.2% had grade 1 PTT pathology (n = 72), 14.3% had grade 2 pathology (n = 31), and 2.8% had grade 3 pathology (n = 6). When stratified by location, 29.0% of patients (n = 63) had inframalleolar abnormalities, 11.5% had retromalleolar pathology (n = 25), and 11 patients had supramalleolar pathology (5.1%). Four patients had PTT subluxation or dislocation. Age was significantly associated with PTT pathology (P = .02). A higher proportion of patients with supramalleolar (81.8%) and retromalleolar (72.0%) PTT pathology were women compared with patients who had inframalleolar (57.1%) PTT pathology. A higher proportion of patients with supramalleolar and retromalleolar PTT pathology had grade 2 tears compared with those with inframalleolar PTT pathology (36.4% for supramalleolar, 44.0% for retromalleolar, and 22.2% for inframalleolar pathology). CONCLUSIONS: We present one of the largest studies on PTT pathology. PTT pathology can occur in the supramalleolar area, a region that often is not assessed on imaging. Although data are unavailable with regard to whether the natural history of supramalleolar PTT is different from that of other regions, patients with supramalleolar PTT pathology had more severe grades of tear and increased prevalence of tenosynovitis and were more often women. It is essential to recognize supramalleolar PTT pathology so that consequences of nontreatment such as medial arch collapse can be prevented.

A pilot study of comprehensive ultrasound education at the Wayne State University School of Medicine: a pioneer year review.

OBJECTIVE: Ultrasound is a versatile diagnostic modality used in a variety of medical fields. Wayne State University School of Medicine (WSUSOM) is one of the first medical schools in the United States to integrate an ultrasound curriculum through both basic science courses and clinical clerkships. METHODS: In 2006, 25 portable ultrasound units were donated to WSUSOM. First-year medical students were provided an ultrasound curriculum consisting of 6 organ-system sessions that addressed the basics of ultrasound techniques, anatomy, and procedural skills. After the last session, students were administered 2 anonymous and voluntary evaluations. The first assessed their overall experience with the ultrasound curriculum, and the second assessed their technical skills in applying ultrasound techniques. RESULTS: Eighty-three percent of students agreed or strongly agreed that their experience with ultrasound education was positive. On the summative evaluation, nearly 91% of students agreed or strongly agreed that they would benefit from continued ultrasound education throughout their 4 years of medical school. Student performance on the technical assessment was also very positive, with mean class performance of 87%. CONCLUSIONS: As residency programs adopt ultrasound training, medical school faculty should consider incorporating ultrasound education into their curriculum. Portable ultrasound has the potential to be used in many different settings, including rural practice sites and sporting events. The WSUSOM committee's pilot ultrasound curriculum will continue to use student feedback to enhance the ultrasound experience, helping students prepare for challenges that they will face in the future.

Yttrium-90 microspheres (TheraSphere) treatment of unresectable hepatocellular carcinoma: downstaging to resection, RFA and bridge to transplantation.

PURPOSE: To present the clinical data of 35 patients with T3 unresectable hepatocellular carcinoma (HCC) that were treated with (90)Y with the specific intent of downstaging to resection, radiofrequency ablation (RFA) candidate, United Network for Organ Sharing (UNOS) stage T2 or liver transplantation. MATERIALS AND METHODS: One hundred fifty patients with unresectable HCC were treated with (90)Y microspheres. Of these, 35 patients were UNOS stage T3 at the time of treatment. Patients were followed for clinical toxicities, alterations in model for end-stage-liver disease (MELD) score, tumor response, downstaging to RFA, resection, transplantation, and survival. RESULTS: Nineteen of 34 patients (56%) were successfully downstaged from T3 to T2 following treatment. 11 of 34 (32%) patients treated were downstaged to target lesions measuring 3.0 cm or less. Twenty-three of 35 (66%) were downstaged to either T2 status, lesion < 3.0 cm (RFA candidate), or resection. Seventeen of 34 (50%) had an objective tumor response by WHO criteria. Eight patients (23%) were successfully downstaged and underwent OLT following treatment. 1, 2, and 3-year survival was 84%, 54%, and 27%, respectively. Median survival by Kaplan-Meier analysis for the entire cohort was 800 days. CONCLUSION: These data suggest that intra-arterial (90)Y microspheres can be used as a bridge to transplantation, surgical resection, or RFA.