Diagnostic capabilities of I-131, TI-201, and Tc-99m-MIBI scintigraphy for metastatic differentiated thyroid carcinoma after total thyroidectomy.

We investigated the diagnostic capabilities of I-131, Tl-201, and Tc-99m-MIBI (hexakis-2-methoxyisobutyl- isonitrile) scintigraphy for thyroid cancer metastases after total thyroidectomy over the entire body and for every locus before and after thyroid bed ablation. After total thyroidectomy of thyroid cancer, 36 cases were subjected to I-131 treatment 64 times. They consisted of 17 men and 19 women with 31 papillary carcinomas and 5 follicular carcinomas. Their ages were 22--75(an average of 60.5+/-12.3) years. I-131 scintigraphy(I-131), Tl-201 scintigraphy(Tl-201), and Tc-99m- MIBI scintigraphy (Tc-99m-MIBI) were performed. We defined the metastases as those cases in which serum thyroglobulin (Tg)increased significantly or in which we were able to prove the lesions on CT (computed tomography), MRI (magnetic resonance imaging) or bone scintigram. Three radiology medical specialists visually evaluated each scintigram and calculated the sensitivity, specificity, and likelihood ratio. For whole-body sensitivity, both Tl-201 and Tc-99m-MIBI were high before ablation and I-131 was high after ablation. Before ablation, the negative likelihood ratio was less than 0.1 for Tl-201 and Tc-99m-MIBI, while the positive likelihood ratio was more than 10 for Tl-201. After ablation, the positive likelihood ratio for I-131, Tl-201, and Tc-99m-MIBI was more than 10. The sensitivity of the mediastinum was appropriate, except for I-131 before ablation, and the sensitivity of the lung before and after ablation was inferior for either tracer. The specificity of the cervix for I-131 before ablation was markedly deteriorated, but it increased after ablation.</p

Factors Influencing Breast Density in Japanese Women Aged 40-49 in Breast Cancer Screening Mammography

A relatively large number of women in their 40s with high-density breasts, in which it can be difficult to detect lesions, are encountered in mammography cancer screenings in Japan. Here, we retrospectively investigated factors related to breast density. Two hundred women (40-49 years old) were examined at the screening center in our hospital. Multivariate analysis showed that factors such as small abdominal circumference, high HDL cholesterol, and no history of childbirth were related to high breast density in women in their 40s undergoing mammography. Other non-mammographic screening methods should be considered in women with abdominal circumferences ＜76cm, HDL-C >53mg/dl, and no history of childbirth, as there is a strong possibility of these women having high-density breasts that can make lesion detection difficult

Differentiation of thyroid nodules using Tl-201 scintigraphy quantitative analysis and fine-needle aspiration biopsy.

We studied the differentiation of thyroid nodules using fine-needle aspiration biopsy (FNA) and Tl-201 scintigraphy quantitative analysis. One-hundred and thirty-one thyroid nodules were examined: 83 follicular lesions (58 benign and 25 malignant lesions) and 48 non-follicular lesions (8 benign and 40 malignant lesions). During Tl-201 scintigraphy examinations, an early and a delayed image were acquired 10 and 120 min after an intravenous injection, respectively. The T/N ratio (counts of nodular lesion/counts of contralateral normal thyroid tissue) of each image was calculated quantitatively. We assessed the ability of the Tl-201 scintigraphy and of the FNA analysis to differentiate benign and malignant lesions and determined the cut-off levels for the assays. For the follicular lesions, the area under the ROC (Receiver Operating Characteristic) curve (Az) for the Tl-201 scintigraphy data was greater than that for the FNA data. For the non-follicular lesions, the Az for the FNA data was greater than that for the Tl-201 scintigraphy data. We set cut-off levels at 1.370 for follicular lesions, and 1.070 for non-follicular lesions. The sensitivity and specificity were 76% and 82.7% for follicular lesions, and 90% and 87.5% for non-follicular lesions, respectively. The overall accuracy of the analysis was 84.0%.</p

Preoperative Graft Volume Assessment with 3D-CT Volumetry in Living-Donor Lobar Lung Transplantations

To determine the effectiveness of living-donor lobar lung transplantation (LDLLT), it is necessary to predict the recipient's postoperative lung function. Traditionally, Date's formula, also called the segmental ratio, has used the number of lung segments to estimate the forced vital capacity (FVC) of grafts in LDLLT. To provide a more precise estimate of graft FVC, we calculated the volumes of the lower lobe and total lung using three-dimensional computed tomography (3D-CT) and the volume ratio between them. We calculated the volume ratio in 52 donors and tested the difference between the segmental volume ratios with a one-tailed t-test. We also calculated the predicted graft FVC in 21 LDLLTs using the segmental ratio pFVC(c) and the volume ratio pFVC(v), and then found the Pearson's correlation coefficients for both pFVC(c) and pFVC(v) with the recipients' actual FVC (rFVC) measured spirometrically 6 months after surgery. Significant differences were found between the segmental ratio and the average volume ratio for both sides (right, p＝0.03;left, p＝0.0003). Both pFVC(c) and pFVC(v) correlated significantly with rFVC at 6 months after surgery (p＝0.007 and 0.006). Both the conventional and the volumetric methods provided FVC predictions that correlated significantly with measured postoperative FVC

Effects of radiofrequency ablation on individual renal function: assessment by technetium-99m mercaptoacetyltriglycine renal scintigraphy.

We quantitatively evaluated total and individual renal function by technetium-99m mercaptoacetyltriglycine (Tc-99m MAG3) renal scintigraphy before and after radiofrequency ablation (RFA) of renal tumors. Eleven patients who underwent Tc-99m MAG3 renal scintigraphy 1 week before and after RFA were evaluated (7 men and 4 women ; age range : 23-83 years ; mean age : 60.6 years). Five patients had solitary kidneys, and five had normally or minimally functioning contralateral kidneys. One patient had a renal cell carcinoma in the contralateral kidney. One patient with a solitary kidney underwent RFA a second time for a residual tumor. In patients with a solitary kidney, MAG3 clearance decreased after 5 of 6 RFAs, and in patients with a normally functioning contralateral kidney, MAG3 clearance decreased after 4 of 5 RFAs, but no significant differences were observed between before and after treatments. In addition to the total MAG3 clearance, the split MAG3 clearance was evaluated in patients with a normally functioning contralateral kidney. MAG3 clearance decreased in 4 of 5 treated kidneys, while it adversely increased in the contralateral kidneys after 4 of 5 RFAs. No significant differences, however, were observed between before and after treatments. The results of our study revealed no significant differences in sCr, BUN, CCr, or MAG3 clearance between pre- and post-RFA values. These results support data regarding the functional impact and safety of renal RFA in published reports. We evaluated total and individual renal function quantitatively using Tc-99m MAG3 renal scintigraphy before and after treatment. This scintigraphy was very useful in assessing the effects of RFA on renal function

The Usefulness of Pre-Radiofrequency Ablation SUVmax in 18F-FDG PET/CT to Predict the Risk of a Local Recurrence of Malignant Lung Tumors after Lung Radiofrequency Ablation

The aim of the present study was to assess the diagnostic usefulness of Fluorine-18 fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) in the prediction of local recurrence of malignant lung tumors by analyzing the pre-radiofrequency ablation (RFA) maximal standardized uptake value (SUVmax). We performed a historical cohort study of consecutive malignant lung tumors treated by RFA from January 2007 to May 2008 at Okayama University Hospital. We selected only lung tumors examined by PET/CT within 90 days before RFA and divided them (10 primary and 29 metastatic) into 3 groups according to their tertiles of SUVmax. We calculated recurrence odds ratios in the medium group and the high group compared to the low group using multivariate logistic analysis. After we examined the relationship between SUVmax and recurrence in a crude model, we adjusted for some factors. Tumors with higher SUVmax showed higher recurrence odds ratios (medium group;1.84, high group;4.14, respectively). The tumor size also increased the recurrence odds ratio (2.67);we thought this was mainly due to selection bias because we excluded tumors less than 10mm in diameter. This study demonstrated the pre-RFA SUVmax in PET/CT may be a prognostic factor for local recurrence of malignant lung tumors

Evaluating Low-kV Dual-source CT Angiography by High-pitch Spiral Acquisition and Iterative Reconstruction in Pediatric Congenital Heart Disease Patients

We retrospectively evaluated the qualities of pediatric cardiovascular dual-source computed tomography (DSCT) images reconstructed by sinogram-affirmed iterative reconstruction (SAFIRE) and filtered back projection (FBP). We analyzed the cases of 287 congenital heart disease (CHD) patients < 5 years old, referred to our department in August 2013-March 2015. We divided them into two groups according to tube voltage (70 kVp, n=147; 80 kVp, n=140). All images were acquired by a CARE kV system and reconstructed by FBP and SAFIRE. The attenuation, noise, and signal-to-noise ratio (SNR) at each region of the heart and great vessels were measured. The volume CT dose index and dose-length product values were recorded. Compared to FBP, reconstruction by SAFIRE showed that the attenuation volume was significantly lower by 0.4% except for the ascending aorta (p<0.05), the noise value was lower by about 20% (p<0.05), and the SNR was higher by approx. 25% (p<0.05). The radiation dose in the 70 kVp group was significantly lower than that in the 80 kVp group. No significant differences in SNR were observed between the patient groups. DSCT image acquisition with SAFIRE using the CARE kV system results in low image noise and radiation dose in pediatric patients with CHD

Endometrial Polyps:MR Imaging Features

The purpose of this study is to evaluate the diagnostic usefulness of magnetic resonance imaging (MRI) characteristics of endometrial polyps in order to differentiate them from other endometrial lesions. MRI was retrospectively reviewed in 40 patients with pathologically proven endometrial polyps. Special attention was paid to the sizes, shapes, margins, internal structures, signal intensities, and post-contrast enhancement patterns. A central fibrous core, intratumoral cysts, and hemorrhage were seen in 30 (75%), 22 (55%), and 14 (35%) patients, respectively. The predominant signal intensity of the lesions showed iso-to slightly low signal intensity relative to the endometrium on T2-weighted images in 36 (90%), low signal intensity on diffusion-weighted images in 32 (80%), and strong or moderate enhancement on enhanced T1-weighted images in 28 patients (70%), respectively. In 32 (80%) patients, the endometrial polyps showed global or partial early enhancement. On dynamic study, rapid enhancement with a persistent strong enhancement pattern was seen in 17 (42.5%) and a gradually increasing enhancement pattern was seen in 17 patients (42.5%). These MRI features can be helpful to distinguish the endometrial polyps from various other endometrial lesions

Functional evaluation of lung by Xe-133 lung ventilation scintigraphy before and after lung volume reduction surgery (LVRS) in patients with pulmonary emphysema.

We evaluated the respiratory functions of patients with pulmonary emphysema who underwent lung volume reduction surgery (LVRS) by the mean transit time (MTT) with Xe-133 lung ventilation scintigraphy, forced expiration volume in 1 sec (FEV1.0), residual volume (RV), distance walked in 6 min (6-min walk), and the Hugh-Jones classification (H-J classification) before and after LVRS. In 69 patients with pulmonary emphysema (62 men, 7 women; age range, 47-75 years; mean age, 65.4 years +/- 6.1, preoperative H-J classification, III (two were II)-V) who underwent LVRS, all preoperative and postoperative parameters (MTT 3 weeks after LVRS and the others 3 months after LVRS) were judged statistically by the Wilcoxon signed-ranks test and Odds ratio. Every postoperative parameter was improved with a significant difference (P &#60; 0.05) compared to preoperative parameters. MTT at 3 weeks after LVRS was not associated with %FEV1.0 and the H-J classification at 3 months after LVRS, but was associated with RV and a 6-min walk at 3 months after LVRS. MTT was useful for the clinical evalution of aerobic capability after LVRS.</p