Using a Motion Sensor-Equipped Smartphone to Facilitate CT-Guided Puncture.

PURPOSE: To demonstrate the use of "Smart Puncture," a smartphone application to assist conventional CT-guided puncture without CT fluoroscopy, and to describe the advantages of this application. MATERIALS AND METHODS: A puncture guideline is displayed by entering the angle into the application. Regardless of the angle at which the device is being held, the motion sensor ensures that the guideline is displayed at the appropriate angle with respect to gravity. The angle of the smartphone's liquid crystal display (LCD) is also detected, preventing needle deflection from the CT slice image. Physicians can perform the puncture procedure by advancing the needle using the guideline while the smartphone is placed adjacent to the patient. In an experimental puncture test using a sponge as a target, the target was punctured at 30°, 50°, and 70° when the device was tilted to 0°, 15°, 30°, and 45°, respectively. The punctured target was then imaged with a CT scan, and the puncture error was measured. RESULTS: The mean puncture error in the plane parallel to the LCD was less than 2°, irrespective of device tilt. The mean puncture error in the sagittal plane was less than 3° with no device tilt. However, the mean puncture error tended to increase when the tilt was increased. CONCLUSION: This application can transform a smartphone into a valuable tool that is capable of objectively and accurately assisting CT-guided puncture procedures.

Magnetic resonance evaluation of brain metastases from systemic malignances with two doses of gadobutrol 1.0 m compared with gadoteridol: a multicenter, phase ii/iii study in patients with known or suspected brain metastases.

OBJECTIVES: To determine the efficacy and safety of 2 doses of gadobutrol 1.0 M (0.1 and 0.2 mmol/kg body weight [BW]), compared with gadoteridol 0.5 M (0.2 mmol/kg BW), in contrast-enhanced magnetic resonance imaging (CE-MRI) of brain metastases in patients with known or suspected brain metastases from systemic malignancies. The study also compared the usefulness of gadobutrol in treatment planning for stereotactic radiosurgery (SRS). MATERIALS AND METHODS: This was a Phase II/III, multicenter, single-blind, randomized, controlled, crossover, intraindividual comparison study. Each patient underwent one MRI study examination with gadobutrol and the other with gadoteridol, each at a dose of 0.1 mmol/kg BW, administered twice, for a total dose of 0.2 mmol/kg BW. Image acquisition was carried out after the first and second doses of gadobutrol, but only after the second dose of gadoteridol. Contrast agents were assigned in a randomized order and their administration separated by an interval of 1 to 14 days. Images were evaluated through blinded readings by 3 independent experienced radiologists. Treatment planning for SRS was assessed in a blinded manner, as a consensus between a diagnostic neuroradiologist and a radiation oncologist, in addition to the clinical investigator's assessment. The safety and tolerability of gadobutrol and gadoteridol were evaluated in all patients who received the study drugs. The primary efficacy variable was the number of lesions detected in CE-MRI images; the secondary efficacy variables were the degree of contrast enhancement and border delineation of lesions, and experts' confidence in treatment planning for SRS. RESULTS: A total of 175 patients were enrolled and randomized, with 164 (93.7%) included in the safety analysis set, and 151 (86.2%) evaluable in the efficacy analysis. The mean number of detected lesions per patient using the average of the 3 blinded readers was 6.28, 6.92, and 6.87 for gadobutrol 0.1 and 0.2 mmol/kg BW, and gadoteridol 0.2 mmol/kg BW, respectively. Noninferiority of gadobutrol (both doses) to gadoteridol 0.2 mmol/kg BW was demonstrated. The degree of contrast enhancement and the border delineation of each lesion were categorized as "good" or "excellent" for most lesions for both agents. Almost all enhanced images were rated as "confident" in treatment planning for SRS. Sixty-five (43%) and 62 (41%) patients in the gadobutrol 0.1 and 0.2 mmol/kg BW groups, respectively, were selected as eligible for SRS treatment. The percentage of images assessed as "gadobutrol was better than gadoteridol" was higher than that assessed as "gadoteridol was better than gadobutrol" for both doses of gadobutrol. Eight adverse events were reported as being related to the study drug in 7 patients (4.3%) in each group. CONCLUSION: In this study, a single dose of gadobutrol was shown to be noninferior to a double dose of gadoteridol at detecting brain metastases, and could be effectively used for treatment planning in patients eligible for SRS. A dose of gadobutrol 0.1 mmol/kg BW is recommended as the clinical dose for the detection of brain metastases.

Suspicious calcifications in benign breast lesions: a radio-pathologic correlation.

BACKGROUND: Breast cancer screening by mammography (MMG) has recently increased in Japan. Suspicious lesions are therefore being detected more and more by MMG and the number of benign biopsies is increasing. It is thus important to examine which pathologically benign lesions were read as suspicious on MMG to reduce the number of biopsies in the case of benign breast lesions. METHODS: Of 299 category 3 or 4 lesions on MMG, 39 histologically benign lesions with calcification were reviewed and compared with the mammograms by a pathologist and a radiologist. The Japan Mammography Guidelines were used for MMG interpretation. RESULTS: In mastopathy lesions, small round segmental calcifications and pleomorphic clustered calcifications were assessed as suspicious. The suspicious type of calcification in fibroadenoma was small round clustered. The calcifications in fibroadenoma may be seen as small round when the fibroadenoma is rather young, and assessed as suspicious. CONCLUSIONS: Some types of calcifications in mastopathy and fibroadenoma were assessed as borderline by MMG. We should therefore collect data from more benign cases with suspicious calcifications on MMG and elucidate the diagnostic criteria in MMG findings of such calcifications.

Determination of indication for sentinel lymph node biopsy in clinical node-negative breast cancer using preoperative 18F-fluorodeoxyglucose positron emission tomography/computed tomography fusion imaging.

OBJECTIVE: Sentinel node biopsy (SNB) is indicated for axillary lymph node metastasis-negative cases (N0), but clarification of the indication may increase treatment efficiency. Fluorine-18-labeled 2-fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) may have a high positive predictive value in diagnosis of axillary lymph node metastasis. METHODS: Ninety-two breasts/axillae were analyzed retrospectively in 90 patients (median age 54.6-year old, median primary tumor 1.7 cm). FDG-PET/computed tomography was used to indicate SNB in N0 cases. Axillary lymph node dissection (ALND) was performed in cases that were axillary lymph node metastasis-positive (PET N+) on FDG-PET/CT. RESULTS: Seventy-four (80.4%) and 18 (19.6%) of the 92 axillae were diagnosed as metastasis-negative (PET N0) and PET N+, respectively, by FDG-PET/CT. SNB was performed in 51 of the 74 PET N0 axillae. ALND was performed in 23 PET N0 axillae (at the patients' request) and in all 18 PET N+ axillae. Of the 74 PET N0 axillae, 14 were metastasis-positive (pN+) and 60 were pN0 pathologically, and of the 18 PET N+ axillae, 13 were pN+ and five were pN0. The sensitivity and specificity of FDG-PET/CT for diagnosis of axillary metastasis were 48.1 and 92.3%, respectively, and the positive and negative predictive values were 72.2 and 81.1%, respectively. CONCLUSION: The positive detection rate on FDG-PET/CT was insufficient for determining an indication of SNB. However, use of an appropriate cut-off for SUV(max) (the positive rate was 90.9% with a cut-off of 2.0) and exclusion of surgically biopsied cases may achieve a clinically applicable positive detection rate.

Contrast-enhanced CT evaluation of clinically and mammographically occult multiple breast tumors in women with unilateral early breast cancer.

BACKGROUND: Magnetic resonance imaging mammography is performed to determine the extent of lesions and to detect occult lesions, but preoperative diagnosis by breast computed tomography (CT) is less common. METHODS: We performed a retrospective study of detection of mammographically occult multiple lesions using breast CT. The subjects were 407 female patients (median age: 56 years old; median tumor size: 1.9 cm) with breast cancer who underwent preoperative, contrast-enhanced breast CT. RESULTS: CT detected 73 incidental-enhanced breast nodules (median size: 0.8 cm) in 73 patients that were undetectable by conventional methods. Age, size of the main lesion or laterality of lesions did not differ between patients with and without incidental nodules, but the frequency of mastectomy was significantly higher in those with incidental nodules. Of the 73 incidental nodules, 22 (30%) were in the same quadrant as the main lesion, 26 (36%) were in other quadrants and 25 (34%) were in the opposite breast. On qualitative diagnosis by CT, 48 were suspected to be malignant (66%), 17 benign (23%) and eight non-specific (11%). In histological evaluation of 44 of the 48 nodules suspected to be malignant, 24 were malignant (invasive carcinoma: 22, non-invasive carcinoma: 2); of seven of the 17 nodules suspected to be benign, all were benign; and of three of the eight non-specific nodules, one was non-invasive carcinoma. The discovery rate of clinically and mammographically occult multiple lesions by preoperative breast CT was 6%. CONCLUSION: We conclude that breast CT is useful for the detection of occult lesions and choice of surgical procedure.

Relation between cancer cellularity and apparent diffusion coefficient values using diffusion-weighted magnetic resonance imaging in breast cancer.

PURPOSE: The purpose of this study was to examine the relation between cancer cellularity and the apparent diffusion coefficient (ADC) value using diffusion-weighted magnetic resonance imaging in breast cancer. MATERIALS AND METHODS: The subjects were 27 women who had undergone operation for breast cancer. There were 27 breast cancer lesions, 24 of which were invasive ductal carcinoma (IDC) and 3 of which were noninvasive ductal carcinoma (NIDC). RESULTS: The mean ADC values of IDC, NIDC, and normal breasts were 1.07 +/- 0.19 .10(-3), 1.42 +/- 0.17 .10(-3), and 1.96 +/- 0.21 .10(-3) mm(2)/s, respectively. The mean ADC values of IDC and NIDC were significantly different from that of normal breasts (P < 0.001 each). The mean ADC values were also significantly different between IDC and NIDC (P < 0.001). There was no correlation between the ADC value and cancer cellularity. CONCLUSION: The mean ADC values for breast cancer were significantly different from that of normal breasts. The mean ADC value for breast cancer did not significantly correlate with cancer cellularity but did correlate with histological types.

Comparison of breast cancer detection by diffusion-weighted magnetic resonance imaging and mammography.

PURPOSE: Breast cancer-detecting ability of diffusion-weighted magnetic resonance imaging (DW-MRI) was investigated by comparing the breast cancer detection rates of DW-MRI and mammography (MMG). MATERIALS AND METHODS: The subjects were 48 women who had breast cancer (53 cancer lesions) who underwent DW-MRI before surgery. Altogether, 41 lesions were invasive ductal carcinoma (IDC), 7 were noninvasive ductal carcinoma (NIDC) and 5 were "others." RESULTS: The breast cancer detection rates by MMG and DW-MRI were 84.9% and 94.3% (P < 0.001), respectively. In each classification of histology and size, the detection rate by DW-MRI was higher than that by MMG. In relation to the mammary gland density, the detection rates of fatty, scattered, heterogeneously dense, and extremely dense mammary glands were 100%, 100%, 92.0%, and 83.3%, respectively. The mean apparent diffusion coefficient values of the histologic types were 1.07 +/- 0.17 x 10(-3), 1.50 +/- 0.24 x 10(-3), 1.12 +/- 0.25 x 10(-3), and 2.01 +/- 0.29 x 10(-3) mm(2)/s for IDC, NIDC, others, and normal breast, respectively, showing that the values of IDC and NIDC were significantly different from that of the normal breast (P < 0.001 each). A significant difference was also noted between IDC and NIDC (P < 0.001). CONCLUSION: DW-MRI may be useful for detecting breast cancer in a wide age group of women, including young women with dense mammary glands.

Pulsating renal blood flow distribution measured using power Doppler ultrasound: correlation with hypertension.

Arterial compliance is associated with the first stage of hypertension and atherosclerosis. We propose here a compliance index, which measures pulsating renal blood flow distribution using a power Doppler ultrasound (US). We assessed the relationship between the compliance index and blood pressure and between the compliance index and risk factors of atherosclerosis. The subjects consisted of 136 consecutive patients (96 males, 40 females) who underwent a physical checkup. Ages ranged from 40 to 60 years with a mean of 50.1 years. Patients with past renal disease and/or renal dysfunction were excluded. Using a power Doppler US combined with an ECG-gated and echo-tracking system, we recorded the vascular distribution of the renal parenchyma at 8 to 10 time points during an interval of the R wave of the ECG. Using a color pixel counting technique, we calculated the area (A) corresponding to the colored vascular distribution at power Doppler US. The relationships between A and the time points (t) were fitted to a quadratic equation. The compliance index of renal parenchymal vessels was obtained by twice differentiating the quadratic equation obtained above (d2A/dt2), and taking the result as a new hemodynamic index. In the univariate correlation analysis, the compliance index was correlated with age (r=-0.26, p=0.002), systolic blood pressure (r=-0.33, p=0.0001), diastolic blood pressure (r=-0.45, p<0.0001), serum uric acid (r=-0.28, p=0.001), and body mass index (r=-0.32, p=0.0002). On the multivariate stepwise regression analysis, the compliance index was significantly correlated with diastolic blood pressure (beta=-0.36, p<0.0001) and body mass index (beta=-0.18, p<0.0001). In conclusion, the compliance index is a candidate for a new hemodynamic marker of renal blood flow abnormality caused by hypertension.