Judy M. Racadio

Live 3D Guidance in the Interventional Radiology Suite

OBJECTIVE The development of a C-arm cone-beam CT unit coupled with flat detectors has markedly increased anatomic visualization capabilities for interventional radiology procedures. We present technology in which fluoroscopy and 3D imaging from a cone-beam CT-flat-detector C-arm unit are combined with an integrated tracking and navigation system. A description of the technology and representative clinical cases are presented. CONCLUSION This new combination further increases interventional radiologic capabilities because it provides real-time procedural evaluation and tracking.

Cardiovascular Anomalies in Turner Syndrome: Spectrum, Prevalence, and Cardiac MRI Findings in a Pediatric and Young Adult Population

OBJECTIVE Turner syndrome affects one in 2,500 girls and women and is associated with cardiovascular anomalies. Visualizing the descending thoracic aorta in adults with Turner syndrome with echocardiography is difficult. Therefore, cardiac MRI is the preferred imaging modality for surveillance. Our goals were to use cardiac MRI describe the spectrum and frequency of cardiovascular abnormalities and to evaluate aortic dilatation and associated abnormalities in pediatric patients with Turner syndrome. MATERIALS AND METHODS The cases of 51 patients with Turner syndrome (median age, 18.4 years; range, 6-36 years) were evaluated with cardiac MRI. The characteristics assessed included aortic structure, elongation of the transverse aortic arch, aortic diameter at multiple locations, and coarctation of the aorta (CoA). Additional evaluations were made for presence of bicuspid aortic valve (BAV), and partial anomalous pulmonary venous return (PAPVR). Associations between the cardiac MRI data and the following factors were assessed: age, karyotype, body surface area, blood pressure, and ventricular sizes and function. RESULTS Sixteen patients (31.4%) had elongation of the transverse aortic arch, eight (15.7%) had CoA, 20 (39.2%) had BAV, and eight (15.7%) had PAPVR. Aortic dilatation was most common at the aortic sinus (30%). Elongation of the transverse aortic arch was associated with CoA (p < 0.01) and BAV (p < 0.05). Patients with elongation of the transverse aortic arch had dilated aortic sinus (p < 0.05). Patients with PAPVR had increased right heart mass (p < 0.05), increased ratio of main pulmonary artery to aortic valve blood flow (p = 0.0014), and increased right ventricular volume (p < 0.05). CONCLUSION Cardiovascular anomalies in pediatric patients with Turner syndrome include aortic abnormalities and PAPVR. The significant association between elongation of the transverse aortic arch and CoA, BAV, and aortic sinus dilatation may contribute to increased risk of aortic dissection. The presence of PAPVR can be hemodynamically significant. These findings indicate that periodic cardiac MRI screening of persons with Turner syndrome is beneficial.

Anatomic distribution of renal artery stenosis in children: implications for imaging

BackgroundRenal artery stenosis (RAS) causes significant hypertension in children. Frequently, pediatric RAS occurs with systemic disorders. In these cases, stenoses are often complex and/or include long segments. We believed that hypertensive children without comorbid conditions had a different lesion distribution and that the difference might have implications for imaging and treatment.ObjectiveTo identify locations of RAS lesions in these hypertensive children without comorbid conditions.Materials and methodsPatients who had renal angiography for hypertension from 1993 to 2005 were identified. Patients with systemic disorders, renovascular surgery, or normal angiograms were excluded. The angiograms of the remaining patients were reviewed for number, type, and location of stenoses.ResultsEighty-seven patients underwent renal angiography for hypertension; 30 were excluded for comorbid conditions. Twenty-one of the remaining 57 patients had abnormal angiograms; 24 stenoses were identified in those patients. All were focal and distributed as follows: 6 (25%) main renal artery, 12 (50%) 2nd order branch, 3 (12.5%) 3rd order branch, and 3 (12.5%) accessory renal artery.ConclusionHypertensive children without comorbid conditions who have RAS usually have single, focal branch artery stenoses. This distribution supports angiography in these patients because of its superior sensitivity in detecting branch vessel disease and its therapeutic role in percutaneous transluminal renal angioplasty.

Subcutaneous epidermal inclusion cysts: Ultrasound (US) and MR imaging findings

ObjectiveTo describe the characteristic US and MR findings of subcutaneous epidermal inclusion cysts.Materials and methodsSeventy-nine patients with subcutaneous epidermal inclusion cysts underwent US (n = 70), MR (n = 7), or both (n = 2). On US, the margin, shape, echogenicity, through-transmission, wall, internal debris and vascularity were evaluated. On MR, the shape, wall, signal intensity, internal debris, and enhancement pattern were evaluated.ResultsOn US, characteristic findings were well circumscribed (n = 69, 96%), ovoid-shaped (n = 56, 78%), heterogeneously and mildly echogenic (n = 66, 92%), increased through-transmission (n = 66, 92%) and low echoic rim (n = 48, 67%). Internal debris was seen in 31 cases (43%) and often contained linear echogenic reflections (n = 12, 17%), dark clefts (n = 13, 18%), or a mixture (n = 5, 7%). Most masses showed no Doppler flow (n = 70, 97%). On MR, all cases demonstrated a well-demarcated oval-shaped mass with a surrounding rim. On T1-weighted image (WI), the mass showed slightly high T1 signal in 4/9 (44%) and iso-signal in 5/9 (56%). On T2WI, the mass showed high signal in 6/9 (67%), intermediate in 2/9 (22%), and a target appearance in 1/9 (11%). Internal linear dark T2 signal debris was observed in 4/9 (44%). All lesions showed peripheral rim enhancement without central enhancement.ConclusionsOn US, subcutaneous epidermal inclusion cysts are usually well-circumscribed, oval-shaped, mildly echogenic masses with occasional linear anechoic and/or echogenic reflections, increased through-transmission, hypoechoic rim and no Doppler flow. On MR, an intermediate to high T2 signal mass with occasional low signal debris and no central enhancement can strengthen the diagnosis.

T2 relaxation time changes in distal femoral articular cartilage in children with juvenile idiopathic arthritis: a 3-year longitudinal study.

OBJECTIVE Increased cartilage T2 relaxation time is thought to be an early marker of disease progression in juvenile idiopathic arthritis, because it can identify microstructural changes before damage becomes visible. The purpose of this study was to investigate longitudinal changes in T2 relaxation time mapping (i.e., T2 map) in children with early juvenile idiopathic arthritis and to compare with changes in clinical assessments. SUBJECTS AND METHODS Twenty children (age range, 6.4-16 years) with early juvenile idiopathic arthritis completed at least four evaluations with T2 maps and clinical assessments: at enrollment, at 3 months, and at 1, 2, and 3 years. Sagittal T2 maps of distal femoral cartilage were generated, a region of interest was selected, and a T2 relaxation time profile was generated. The area under the curve from the T2 profile (i.e., T2 value) was correlated with patient age and sex and the following clinical assessments: total knee score, Childhood Health Assessment Questionnaire, physician global assessment, parent global assessment, and total number of active joints. RESULTS There was a significant increase in mean T2 values from 3 months to 2 years (p < 0.05). There was a significant decrease in mean Childhood Health Assessment Questionnaire values between enrollment and 2 years (p < 0.05) and a significant decrease in parent global assessment, physician global assessment, total number of active joints, and total knee score values between enrollment and 1 year (p < 0.05). There were no statistically significant correlations between T2 values and patient age, sex, or clinical assessments. CONCLUSION In patients with early juvenile idiopathic arthritis, T2 maps showed increased T2 values from the 3-month to 2-year follow-up, during which time the clinical assessments improved. This increase likely represents progressive microstructural changes, even though clinical symptoms improved with treatment.

Image Gently: A Web-Based Practice Quality Improvement Program in CT Safety for Children

OBJECTIVE Radiologists want to improve quality and safety to benefit their pediatric patients and to comply with new requirements of the American Board of Radiology for maintenance of certification. The purpose for this article is to describe the development, construction, and content of a free, Web-based practice quality improvement (PQI) module in CT safety for children. CONCLUSION We describe an online tutorial accessible on the Image Gently Website that enables radiologists nationwide to perform PQI in CT safety for pediatric patients.

Complex cloacal malformations: use of rotational fluoroscopy and 3-D reconstruction in diagnosis and surgical planning

A cloacal malformation is a congenital malformation in which the urinary tract, gynecological system and distal rectum fail to separate and form a common channel with a single perineal opening. Precise anatomical information is required to plan surgery and predict prognosis for children with this abnormality. Conventional fluoroscopic studies provide limited information, primarily due to the overlap of structures and inability to make accurate measurements. Rotational fluoroscopy and 3-D reconstruction help clarify overlapping structures and allow for precise measurement of the common channel, thereby helping to predict the complexity of the surgical case as well as the long-term prognosis regarding bowel, bladder and sexual function.

Intrathyroidal thymic tissue mimicking a thyroid nodule in a 4‐year‐old child

A 4 year‐old girl was referred for CT of her neck for suspected submental lymphadenopathy and was found to have an incidental low‐attenuation thyroid mass. Subsequent thyroid ultrasound showed a heterogeneous thyroid mass with punctate areas of increased echogenicity. Cytologic examination was consistent with ectopic intrathyroidal thymic nodule. We review the presentation of ectopic thymic tissue, especially in the thyroid gland.

Varicocele Retrograde Embolization with Boiling Contrast Medium and Gelatin Sponges in Adolescent Subjects: A Clinically Effective Therapeutic Alternative

PURPOSE Varicoceles occur in approximately 15% of adolescent male subjects and may impair future fertility. The present study describes a varicocele treatment technique involving percutaneous retrograde embolization with boiling hot contrast medium and gelatin sponge pledgets. MATERIALS AND METHODS A retrospective review of medical records and imaging of all patients who underwent percutaneous retrograde varicocele embolization from 2005 to 2010 was performed. Pre- and postembolization symptoms, physical findings, and ultrasound findings were documented. Fifteen patients (16 embolizations) were identified, with an average age of 15.9 years (range, 12-18 y). Nine were referred because of persistent varicocele after surgical ligation. Three had grade 2 and nine had grade 3 varicoceles. Two had grade 1 varicoceles; one was painful and one was associated with poor semen quality. One varicocele was not clinically evident, but was associated with persistently decreased testicular size. Nine patients had pain or discomfort, and six had no discomfort. Clinical resolution was defined by a combination of symptom resolution and a lack of physical examination findings of varicocele or findings of treated varicocele. RESULTS Fifteen of the 16 embolizations (94%) were technically successful. Clinical resolution was documented in 14 of 15 patients (95%); one patient experienced a recurrence at 30 months, which was successfully reembolized. One patient experienced temporary paresthesia of the left thigh. There were no major postprocedural complications. Mean follow-up duration was 11 months. CONCLUSIONS Retrograde embolization of varicoceles in adolescent subjects with the use of boiling hot contrast medium and gelatin sponges is a promising technique that appears effective.

Real-Time In Vivo Characterization of Primary Liver Tumors With Diffuse Optical Spectroscopy During Percutaneous Needle Interventions: Feasibility Study in Woodchucks

ObjectiveThis study presents the first in vivo real-time optical tissue characterization during image-guided percutaneous intervention using near-infrared diffuse optical spectroscopy sensing at the tip of a needle. The goal of this study was to indicate transition boundaries from healthy tissue to tumors, namely, hepatic carcinoma, based on the real-time feedback derived from the optical measurements. Materials and MethodsFive woodchucks with hepatic carcinoma were used for this study. The woodchucks were imaged with contrast-enhanced cone beam computed tomography with a flat panel detector C-arm system to visualize the carcinoma in the liver. In each animal, 3 insertions were performed, starting from the skin surface toward the hepatic carcinoma under image guidance. In 2 woodchucks, each end point of the insertion was confirmed with pathologic examination of a biopsy sample. While advancing the needle in the animals under image guidance such as fluoroscopy overlaid with cone beam computed tomography slice and ultrasound, optical spectra were acquired at the distal end of the needles. Optical tissue characterization was determined by translating the acquired optical spectra into clinical parameters such as blood, water, lipid, and bile fractions; tissue oxygenation levels; and scattering amplitude related to tissue density. The Kruskal-Wallis test was used to study the difference in the derived clinical parameters from the measurements performed within the healthy tissue and the hepatic carcinoma. Kurtoses were calculated to assess the dispersion of these parameters within the healthy and carcinoma tissues. ResultsBlood and lipid volume fractions as well as tissue oxygenation and reduced scattering amplitude showed to be significantly different between the healthy part of the liver and the hepatic carcinoma (P < 0.05) being higher in normal liver tissue. A decrease in blood and lipid volume fractions and tissue oxygenation as well as an increase in scattering amplitude were observed when the tip of the needle crossed the margin from the healthy liver tissue to the carcinoma. The kurtosis for each derived clinical parameter was high in the hepatic tumor as compared with that in the healthy liver indicating intracarcinoma variability. ConclusionsTissue blood content, oxygenation level, lipid content, and tissue density all showed significant differences when the needle tip was guided from the healthy tissue to the carcinoma and can therefore be used to identify tissue boundaries during percutaneous image-guided interventions.