Detection of Urothelial Carcinoma: Comparison of Reduced-Dose Iterative Reconstruction with Standard-Dose Filtered Back Projection.

PURPOSE: To prospectively assess radiation dose, image quality, and diagnostic performance of computed tomography (CT) urography for detection of urothelial carcinomas by performing reduced-dose scanning with iterative reconstruction (IR) compared with standard-dose scanning with filtered back projection (FBP). MATERIALS AND METHODS: The institutional review board approved the study with written informed patient consent. In total, 2163 patients at high risk for urothelial carcinomas randomly underwent standard-dose scanning with FBP (protocol A, 120 kVp for >80 kg body weight; protocol B, 100 kVp for 50-80 kg body weight) or reduced-dose scanning with IR (protocol C, 100 kVp for >80 kg body weight; protocol D, 80 kVp for 50-80 kg body weight). Objective image quality (signal-to-noise ratio and contrast-to-noise ratio) between the two groups with same weight range was measured for various regions of interest. Subjective image quality (visual image noise, artifact, ureter depiction, and overall image quality) and diagnostic accuracy (per lesion and per patient) were assessed with three- and five-point scores, respectively. RESULTS: Size-specific dose estimate (protocol A vs protocol C, 24.2 mGy vs 19.2 mGy, respectively; protocol B vs protocol D,13.9 mGy vs 8.8 mGy, respectively) was significantly lower in reduced-dose scanning (P < .001 for both). There were significantly higher signal-to-noise and contrast-to-noise ratios in reduced-dose scanning, except for the abdominal aorta (P < .05 for all). There was no significant difference in subjective image quality, except for artifacts in protocols B and D (range, 4-5 vs 3-4; P < .05). Per-lesion diagnostic accuracy was 90.8% (89 of 98, protocol A), 91.3% (105 of 115, protocol B), 92.9% (79 of 85, protocol C), and 88.8% (111 of 125, protocol D). CONCLUSION: Reduced-dose scanning with IR showed dose reduction and no significant difference of image quality in detection of urothelial carcinomas, except for some artifacts in 80-kVp scanning.

Quantification of tricuspid regurgitation using two-dimensional velocity encoding cine: optimal plane and reproducibility.

To determine the optimal plane of two-dimensional velocity-encoding cine (VENC) magnetic resonance (MR) imaging at the tricuspid annulus for quantification of tricuspid regurgitation (TR) and to assess the reproducibility of VENC tricuspid flow measurements. We conducted a retrospective review of MR images of 25 consecutive patients (M:F = 8:17; mean age, 58.5 ± 10.5 years) with TR. VENC was performed twice orthogonal to the tricuspid annulus plane during the end-diastolic (ED) and end-systolic (ES) phases. The TR fraction was quantified at each plane as retrograde flow/antegrade flow and additionally as retrograde flow of the ED plane/antegrade flow of the ES plane (combined plane method). The conventional method to determine the TR amount [right ventricular stroke volume (RVSV)-pulmonary antegrade flow] and TR fraction (TR amount/RVSV) was used as the reference standard. There were no differences between TR amount and retrograde flow of the ED plane (65.3 ± 43.4 vs. 70.5 ± 36.1 ml, P = 0.361) between the RVSV and the antegrade flow of the ES phase (124.2 ± 46.1 vs. 128.0 ± 45.0 ml, P = 0.612) or in TR fraction between the conventional and combined plane methods (48.8 ± 19.2 vs. 56.3 ± 24.3 %, P = 0.08). The retrograde flow of the ED phase was best correlated with TR amount [intraclass correlation coefficient (ICC) = 0.859] and antegrade flow of ES with RVSV (ICC = 0.808). The TR fraction of the combined plane method was best correlated with the conventional method (ICC = 0.694). Interobserver agreement of VENC flow measurements was excellent (ICC, 0.939-0.993). The optimal method for quantification of TR using tricuspid annular VENC was the combined plane method, which divides the retrograde flow of the ED plane by the antegrade flow of the ES plane. Tricuspid flow measurements using VENC showed excellent reproducibility.

Clinical findings and outcomes in patients with possible usual interstitial pneumonia.

BACKGROUND: Patients with possible usual interstitial pneumonia (UIP) constitute a substantial group, and their clinical characteristics and outcomes are not well defined. We compared the clinical characteristics and survival between patients with possible UIP and the UIP pattern. METHODS: We evaluated 62 patients with possible UIP and 544 patients with the UIP pattern. Both groups were diagnosed by clinical characteristics and high-resolution computed tomography (HRCT) findings. Two radiologists performed radiological evaluation based on the new idiopathic pulmonary fibrosis (IPF) guidelines. Two risk-stratification methods were used to compare UIP pattern and possible UIP patients. RESULTS: The groups had similar demographic and clinical characteristics. Pulmonary function tests revealed no significant differences in lung volumes between the 2 groups. However, DLCO was significantly lower with the UIP pattern than with possible UIP (p = 0.004). Multivariate analysis showed age, sex, and carbon monoxide diffusing capacity (DLCO) as important independent variables for survival. The UIP HRCT pattern did not affect survival (hazard ratio, 0.83; 95% confidence interval, 0.51-1.24; p = 0.32). Possible UIP was not associated with prognosis when independent predictors for survival rate and propensity score were considered. In the case-control study, the 3-year survival rate was 44.6% in the UIP pattern group and 56.8% in the possible UIP group (p = 0.16). CONCLUSIONS: Clinical characteristics and outcomes were similar in possible UIP and UIP patients, except for differences in DLCO. The UIP pattern itself did not affect survival.

Digital tomosynthesis for evaluating metastatic lung nodules: nodule visibility, learning curves, and reading times.

OBJECTIVE: To evaluate nodule visibility, learning curves, and reading times for digital tomosynthesis (DT). MATERIALS AND METHODS: We included 80 patients who underwent computed tomography (CT) and DT before pulmonary metastasectomy. One experienced chest radiologist annotated all visible nodules on thin-section CT scans using computer-aided detection software. Two radiologists used CT as the reference standard and retrospectively graded the visibility of nodules on DT. Nodule detection performance was evaluated in four sessions of 20 cases each by six readers. After each session, readers were unblinded to the DT images by revealing the true-positive markings and were instructed to self-analyze their own misreads. Receiver-operating-characteristic curves were determined. RESULTS: Among 414 nodules on CT, 53.3% (221/414) were visible on DT. The main reason for not seeing a nodule on DT was small size (93.3%, ≤ 5 mm). DT revealed a substantial number of malignant nodules (84.1%, 143/170). The proportion of malignant nodules among visible nodules on DT was significantly higher (64.7%, 143/221) than that on CT (41.1%, 170/414) (p < 0.001). Area under the curve (AUC) values at the initial session were > 0.8, and the average detection rate for malignant nodules was 85% (210/246). The inter-session analysis of the AUC showed no significant differences among the readers, and the detection rate for malignant nodules did not differ across sessions. A slight improvement in reading times was observed. CONCLUSION: Most malignant nodules > 5 mm were visible on DT. As nodule detection performance was high from the initial session, DT may be readily applicable for radiology residents and board-certified radiologists.

The management of traumatic scalp pseudoaneurysms with manual or US-guided compression.

There are many reports dealing with the treatment of traumatic pseudoaneurysms of the scalp. But, there is no consistent standard of treatment for such lesions, to our knowledge. We reviewed our cases and evaluated the use of manual or ultrasonography (US)-guided compression as a treatment option for patients with traumatic scalp pseudoaneurysm. Four patients with traumatic pseudoaneurysm were enrolled in this study. Among them, three patients underwent manual or US-guided compression (mean size = 5.67 mm) and all the lesions were resolved. In one case, a residual lesion (size = 10 mm) remained after surgical operation (initial size = 20 mm). The lesion regressed after the patient was treated with US-guided compression. Overall, in this study population, four patients (mean = 6.75 mm) were treated with manual or US-guided compression. Although there were only a small number of patients in this study, all the traumatic scalp pseudoaneurysms were treated successfully. We recommend manual or US-guided compression for the treatment of these lesions. Further studies involving a larger number of patients and comparisons with surgical and endovascular data are needed.

C-arm cone-beam CT-guided percutaneous transthoracic needle biopsy of lung nodules: clinical experience in 1108 patients.

PURPOSE: To retrospectively evaluate the diagnostic performance and complications of C-arm cone-beam computed tomography (CT)-guided percutaneous transthoracic needle biopsy (PTNB) in 1108 patients. MATERIALS AND METHODS: This retrospective study was approved by the institutional review board with waiver of patient informed consent. From January 2009 to December 2011, 1108 patients (633 male, 475 female; mean age, 62.4 years ± 12.3 [standard deviation]) with 1116 pulmonary lesions (mean size, 2.7 cm ± 1.7) underwent 1153 cone-beam CT-guided PTNBs. A coaxial system with 18-gauge cutting needles was used. Diagnostic performance, complication rate, influencing factors, and patient radiation exposure were investigated. Variables influencing diagnostic performance and complications were assessed by using uni- and multivariate logistic regression analyses. RESULTS: Among 1153 PTNBs, pathologic analysis showed 1148 (99.6%) were technically successful (766 malignant [66.4%], 323 benign [28.0%], and 59 [5.1%] indeterminate). Sensitivity, specificity, and accuracy for diagnosis of malignancy were 95.7% (733 of 766), 100% (323 of 323), and 97.0% (1056 of 1089), respectively. In regard to diagnostic failures (five technical failures, 33 false-negative findings), lesions 1 cm in diameter or smaller and lesions in the lower lobe were significant risk factors (P = .028 and P = .034, respectively). As for complications, pneumothorax and hemoptysis occurred in 196 (17.0%) and 80 (6.9%) procedures, respectively. Multivariate analysis revealed two or more pleural passages and emphysema along the needle pathway were the two most significant risk factors for pneumothorax, and ground-glass nodules were the most significant risk factor for hemoptysis (P < .001 for all). Virtual guidance was a significant protective factor for both pneumothorax and hemoptysis (P < .001 for both). Mean estimated effective radiation dose through cone-beam CT-guided PTNBs was 7.3 mSv ± 4.1. CONCLUSION: Cone-beam CT-guided PTNB is a highly accurate and safe technique with which to diagnose pulmonary lesions with reasonable radiation exposure.

Features of sequential CT and US-guided biopsy in recurrent Kikuchi disease of the neck: a case report.

A 26-year-old woman presented with recurrent Kikuchi disease 7 years after her initial episode. Computed tomography (CT) and ultrasonography demonstrated enlarged lymph nodes with extensive necrosis at the same site as the initial episode. Cytologic and histologic examinations were not conclusive. CT performed 1 month later demonstrated a complete resolution of the lymphadenopathy, which confirmed the diagnosis of recurrent Kikuchi disease. Care must be taken to avoid misdiagnosis of recurrent Kikuchi disease as tuberculous lymphadenitis.

Sonographic appearances of mucosa-associated lymphoid tissue lymphoma of the submandibular gland confirmed with sonographically guided core needle biopsy.

A 71-year-old man presented with mucosa-associated lymphoid tissue (MALT) lymphoma of the submandibular gland 52 months after initial diagnosis of MALT lymphoma of the lung. Ultrasonography showed a well-demarcated, markedly hypoechoic, heterogeneous solid mass with linear echogenic strands and hypervascularity. Ultrasound-guided core-needle biopsy demonstrated histological findings of MALT lymphoma. Sonographic features of MALT lymphoma of the submandibular gland are characteristic and ultrasound-guided core-needle biopsy may be a suitable replacement for surgical biopsy.

Antiproliferative effect of chitosan-added kimchi in HT-29 human colon carcinoma cells.

The anticancer effects of chitosan-added kimchi were investigated by using an in vitro cellular system with HT-29 human colon carcinoma cells. Two different kinds of chitosan-soluble chitosan with a 90% degree of deacetylation and 3 cps viscosity and nonsoluble chitosan with a 95% degree of deacetylation and 22 cps viscosity-were used as sub-ingredients to increase anticancer effects of kimchi. The soluble chitosan-added kimchi (SK) and nonsoluble chitosan-added kimchi (NK) were stronger growth inhibitors in HT-29 cells than the control kimchi (CK) according to the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay and the growth inhibition test. Treatment with SK and NK induced apoptosis, as determined by 4,6-diamidino-2-phenylindole staining, and resulted in the up-regulation of Bax expression and down-regulation of Bcl-2, cIAP-1, cellular inhibitor of apoptosis-2, cyclooxygenase-2, inhibitory nitric oxide synthase, and nuclear factor kappaB (NF-kappaB) expressions when compared to CK. The antiproliferative and anti-apoptotic effects appeared to be more pronounced in the cells treated with NK. The antiproliferative effects of the chitosan-added kimchi appeared to be associated with the induction of apoptosis through NF-kappaB or an NF-kappaB-dependent pathway. These results suggest that chitosan has potential to be a valuable active ingredient in functional kimchi products with anticancer effects.