Search

Purpose To evaluate the effect of the menstrual cycle on BPE and cancer detectability in an Asian population. Material and methods 266 premenopausal patients with regular menstrual cycles from 24 centers were included, and 176 of them were diagnosed by pathology as having breast cancer. Thirty-five patients were examined in the menstrual phase (days 1–4), 105 in the proliferative phase (days 5–14), and 126 in the secretory phase (days 15–30). Measurement of the following signal intensities (SIs) were obtained: breast tissue on the unaffected side on a pre-contrast image (SI1) and an early-phase image (SI2); the SIs of breast tissue on the affected side on a pre-contrast image (SI3) and an early-phase image (SI4); and the SIs of breast cancer on a pre-contrast image (SI5) and an early-phase image (SI6). We calculated the BPE ratio, i.e., (SI2– SI1)/SI1 and the cancer/background enhancement ratio (C/B) ratio, i.e., (SI6– SI5) / (SI4– SI3). The BPE was classified as minimal, mild, moderate, or marked, and the cancer detectability was classified as excellent, good, or poor independently by two radiologists. Results The average C/B ratio was 20.1, 15.7, and 9.1 at the menstrual, proliferative, and secretory phases (p Conclusion The menstrual phase and the proliferative phase seem to be suitable for breast MRI of Asian women.

The origin of the vertebral artery (VA) varies, though most VAs enter the transverse foramen (TF) of the sixth cervical vertebra. On computed tomography (CT) angiographic images, we evaluated the prevalence of variations of both VA origin and its level of entry into the TF. We retrospectively reviewed CT angiographic images of 2,287 patients obtained using either of two 64-slice multidetector CT scanners. All patients were Japanese and underwent scanning from the aortic arch to the intracranial region; most had or were suspected of having cerebrovascular diseases. The left VA (LVA) arose from the aorta between the left common carotid artery and left subclavian artery in 94 patients (4.1 %) and in other variations in 44 patients (1.9 %). The right VA (RVA) arose from the extreme proximal segment of the right subclavian artery in 72 patients (3.1 %) and in other variations in 14 patients (0.6 %). The LVA entered the sixth TF in 2,127 patients (93.0 %), and the RVA entered the sixth TF in 2,146 patients (93.8 %). Anomalous origin and anomalous entry level into the TF correlated strongly. The total prevalence of variation in the origin of the LVA was 6.0 % and of the RVA, 3.8 %. The total prevalence of variation in entry level into the TF was 7.0 % for the LVA and 6.2 % for the RVA. Recognition and reporting of these variations is important in interpreting CT angiography to prevent complications during surgery of the aortic arch or lower neck.

To compare the diagnostic capability of proton (1H) magnetic resonance spectroscopy (MRS) in differentiating benign from malignant breast lesions on the basis of qualitative and quantitative approaches. We performed single-voxel 1H MRS for 208 breast lesions, identified a clear total composite choline compounds (tCho) peak of signal-to-noise of ≥2 to represent malignancy (qualitative approach), and regarded tCho concentration equal to or greater than the cut-off value to represent malignancy (quantitative approach). We compared the diagnostic ability of both approaches using the Akaike information criterion (AIC) and McFadden’s R 2. Histologically, 169 lesions were malignant; 39 were benign. The qualitative approach demonstrated 84.6 % sensitivity and 51.3 % specificity for differentiating malignant and benign lesions. The mean tCho concentration was 1.13 mmol/kg for malignancy, 0.43 mmol/kg for benignity. The optimal cut-off point was 0.61 mmol/kg, use of which achieved 68.1 % sensitivity and 79.4 % specificity. Calculated AIC and R 2 score suggested the superiority of the quantitative approach for differentiating malignancy. Quantitative MRS provides higher specificity than qualitative MRS for differentiating malignant from benign lesions and could be more useful as an additional examination in routine breast MR imaging. • Magnetic resonance spectroscopy of the breast helps distinguish malignant from benign lesions. • Magnetic resonance spectra demonstrate a choline signal even from benign lesions. • Choline concentration is higher in breast carcinomas than in benign lesions. • Quantitative magnetic resonance spectroscopy differentiates breast malignancies better than qualitative MRS.

Fenestrations of cerebral arteries are most common in the vertebrobasilar (VB) system, and magnetic resonance (MR) angiographic studies of these variations are sparse.We retrospectively reviewed MR angiographic images of 3,327 patients; images were obtained using two 1.5-T imagers and picked up fenestrations of the intracranial vertebral artery (VA), VB junction, and basilar artery (BA) for evaluation.In 92 patients, we found 93 fenestrations (2.80%), which included 18 of the intracranial VA (0.54% prevalence), 6 of the VB junction (0.18%), and 69 of the BA (2.07%). Most VA fenestrations were large, and the posterior inferior cerebellar artery arose from the fenestrated segment in 10 patients (56%). Fenestrations of the VB junction were small and triangular. Sixty-five (94%) of the 69 BA fenestrations were located at the proximal segment and had small slit-like configurations. The anterior inferior cerebellar artery arose from the fenestrated segment in 27 patients (37%). We found 18 cerebral aneurysms in 16 (17%) of the 92 patients with fenestration but detected only one aneurysm at the fenestration.The overall prevalence of fenestrations of the intracranial VB system was 2.77%. We found associated cerebral aneurysms relatively frequently but rarely at the fenestration.

We evaluated the usefulness of quantitative and visual assessment of diffusion-weighted imaging (DWI) of breast tumors to distinguish malignant from benign tumors.The DWI findings of 106 breast lesions (15 benign, 91 malignant) were retrospectively analyzed. The mean apparent diffusion coefficient (ADC) value for each lesion was calculated using b values of 250, 500, 750, and 1000 s/mm(2) as a quantitative assessment. We visually evaluated the signal intensity of each breast lesion on the basis of a spinal signal intensity in DWI (b = 1000 s/mm(2)) and compared the mean ADC values using a threshold mean ADC +1.65 × standard deviation (SD) for malignant and benign breast lesions. Obviously strong signal intensity of the lesion relative to that of the spinal cord on DWI signifies malignancy.The mean ADC value for benign lesions (1.50 ± 0.38 × 10(-3) mm(2)/s) was significantly higher than that for malignant lesions (0.98 ± 0.19 × 10(-3) mm(2)/s), with 94.5% sensitivity, 80% specificity, and 92.5% accuracy. Sensitivity for visual assessment was 91.5%, specificity was 33.3%, and total accuracy was 82.5%.ADC values, but not visual assessment, may be useful for differentiating benign and malignant breast tumors.

We measured diffusion changes in the brains of children with neurofibromatosis type 1 (NF1). Using diffusion-weighted and conventional magnetic resonance (MR) images of 42 children with NF1 (19 girls, 23 boys; 7 months-16 years, mean 6.8 years) and 42 age-matched controls (20 boys, 22 girls; 6 months-17 years, mean, 6.9 years), we calculated the apparent diffusion coefficient (ADC) from the automatically generated ADC maps and placed regions of interest in the pons, middle cerebellar and cerebral peduncles, thalami, globus pallidi and frontal white matter. Evaluating only normal-appearing regions on conventional images, we compared mean ADCs using the unpaired Student t test. Means were not significantly different in frontal white matter but were larger in the other regions in the NF1 (P < 0.01). Although conventional MR showed normal intensity, ADCs of the pons, middle cerebellar and cerebral peduncles, thalami and globus pallidi were significantly larger in the NF1.

A persistent dorsal ophthalmic artery (OA) is a rare variation that originates from the cavernous segment of the internal carotid artery (ICA) and enters the orbit via the superior orbital fissure (SOF). Occasionally, the OA also arises from the middle meningeal artery (MMA) and enters the orbit via the SOF. These two major variations of the OA have not been well described by magnetic resonance (MR) angiography. We evaluated their prevalence on MR angiography at 3 T.We retrospectively reviewed our database of MR angiographic images obtained using a 3 T imager. Of images of 846 patients, we evaluated those of 826 patients (1,652 OAs) with special attention to OA origin and its course into the orbit. We excluded images of the 20 because quality was insufficient to assess.We found 7 (0.42%) persistent dorsal OAs among 1,652 OAs (right/left, 6/1; male/female, 3/4). Twenty-four (1.45%) OAs arose from the MMA (right/left/bilateral, 11/5/4; male/female, 10/10), three of which also demonstrated a small normally branching OA. In one patient, we observed both right persistent dorsal OA and left OA arising from the MMA.Per OA, the prevalence of persistent dorsal OA was 0.42% and of OA arising from the MMA, 1.45%, with a tendency toward right-side predominance. OA arising from the MMA can be seen bilaterally; preprocedural knowledge of this variation is important because of the danger associated with endovascular procedures of the external carotid system when the OA arises from the MMA.

To evaluate the frequency and common locations of myocardial fat and its associated factors using coronary CT angiography (CCTA) in patients without cardiac disease.Using CCTA findings for 298 consecutive patients without cardiac disease, we categorized the myocardium into nine locations, scored fat in those locations, and correlated the fat score with the thickness of the right ventricular (RV) free wall and factors including gender, age, and body mass index (BMI) as well as history of diabetes mellitus, hypertension (HT), and dyslipidemia.We observed myocardial fat in 68.5 % of patients, most commonly in the RV outflow tract (RVOT, 64.1 %), followed by the base (42.3 %) and middle (28.9 %) of the RV free wall, RV trabeculations (22.5 %), and the left ventricular apex (11.4 %). The RV free wall thickened significantly with increasing fat score. Dependent variables for myocardial fat were female gender (P 0.0001), age ≥65 years (P = 0.0043), BMI ≥25 (P = 0.0050), and HT (P = 0.0139).Myocardial fat is a common finding on CCTA in patients without cardiac disease, is often observed in the RVOT, and is more frequent in female patients, those older than 65 years, those with BMI ≥25, and those with HT.

The left common carotid artery (LCCA) is usually a second branch of the aortic arch that arises between the brachiocephalic trunk (BCT) and left subclavian artery; relatively frequently, it also arises from or shares a common origin with the BCT. In patients with LCCA of anomalous origin, transfemoral catheterization into the LCCA is sometimes difficult, and transbrachial or transradial approach may be recommended. We evaluated the prevalence of these variations on computed tomography (CT) angiography. We retrospectively reviewed CT angiographic images of 2,357 patients obtained using either of two 64-slice multidetector CT scanners. All patients were Japanese and underwent scanning from the aortic arch to the intracranial region; most had or were suspected of having cerebrovascular diseases. We evaluated CT angiographic images of 2,352 patients after excluding four patients with LCCA occluded at its origin. The LCCA arose from the BCT in 141 patients (6.0 %) and had a common origin with the BCT in 130 patients (5.5 %). We found 11 aberrant right subclavian artery (0.47 %), and four of the 11 patients (36 %) had LCCA of common origin with the right common carotid artery, forming a bicarotid trunk (prevalence: 0.17 %). The total prevalence of variations of LCCA origin diagnosed by CT angiography was 11.7 %.

Persistent hypoglossal artery (PHA) is the second most common anastomosis between the carotid and vertebrobasilar systems and demonstrates some variations. We evaluated the prevalence of PHA on computed tomography (CT) angiography. We also evaluated characteristic features of PHA and its variants on magnetic resonance (MR) angiography.We retrospectively reviewed our database of 2,074 CT angiographic images obtained using either of two 64-slice multidetector CT scanners. We also reviewed our database of 7,646 MR angiographic images obtained using either of two 1.5-T or one 3.0-T imager. We could not determine the exact number of patients whose MR angiography included the hypoglossal canal. Most patients had or were suspected of having cerebrovascular diseases.We found six usual PHAs arising from the cervical internal carotid artery on CT angiography among 2,074 patients. On MR angiography, we also found six additional usual PHAs (total 12, right/left = 6/6, male/female = 3/9), three right PHAs originating from the external carotid artery (ECA), and two posterior inferior cerebellar arteries (PICAs) arising from the ECA without connection to the vertebral artery.The prevalence of usual PHA diagnosed by CT angiography was 0.29 %, slightly higher than that reported for angiography and may be due to selection bias in the examined patients. We propose naming usual PHA "type 1 PHA"; PHA originating from the ECA, of which we found three, "type 2 PHA"; and PICA arising from the ECA, of which we found two, "type 2 PHA variant."

A persistent trigeminal artery (PTA) is the most common carotid-vertebrobasilar anastomosis. A cerebellar artery that arises from the precavernous segment of the internal carotid artery (ICA) without connecting to the basilar artery is regarded as a PTA variant. Our study aimed to determine the incidence of PTA and its variants and classify them based on magnetic resonance (MR) angiography.We retrospectively reviewed cranial images of 3,626 patients who underwent MR angiography in our institution from April 1, 2007 through December 31, 2009. We ultimately reviewed and analyzed images of 3,491 patients (2,066 men, 1,425 women) after excluding 135 with unilateral or bilateral ICA occlusion or suboptimal image quality.We found 12 cases of PTA (7 men, 5 women; right 4, left 8; incidence; 0.34%) and 6 of PTA variants (3 men, 3 women; right 3, left 3; incidence; 0.17%). 11 of the 12 PTAs were lateral type; 1 was medial. In two of the lateral-type cases, the superior cerebellar artery (SCA) arose from the PTA. Among the six variants, the anterior inferior cerebellar artery (AICA) arose in five and the posterior inferior cerebellar artery (PICA), in one.On MR angiography, the incidence of PTA was 0.34% and of PTA variants, 0.17%. Left PTA was twice as frequent as right PTA, but with no statistical significance. Medial-type PTA was extremely rare. AICA arose in most PTA variants. Rarely, a lateral-type PTA gave rise to the cerebellar artery.

The craniovertebral junction is clinically important. The vertebral artery (VA) in its several variations runs within this area. We report the prevalence of these VA variations on magnetic resonance angiography (MRA). We retrospectively reviewed MRA images, obtained using two 1.5-T imagers, of 2,739 patients, and paid special attention to the course and branching of the VA at the level of the C1–2 vertebral bodies. There were three types of VA variation at the C1–2 level: (1) persistent first intersegmental artery (FIA), (2) VA fenestration, and (3) posterior inferior cerebellar artery (PICA) originating from the C1/2 level. The overall prevalence of these three variations was 5.0%. There was no laterality in frequency, but we found female predominance (P

It is well known that the occipital artery (OA) can arise from the internal carotid artery (ICA) or vertebral artery (VA). However, the incidence of an anomalously originating OA has not been reported. We investigate its incidence and characteristic features on magnetic resonance angiography (MRA). We retrospectively reviewed MRA images of 2,866 patients that included the carotid bifurcation; images were obtained using a standard noncontrast MRA protocol and two 1.5-T MR units. We diagnosed six cases (seven arteries) of anomalously originating OA, which represented an incidence of 0.21%. The OA arose from the ICA in four patients (five arteries), from the carotid bifurcation in one, and from the VA in one. Five of the seven arteries occurred on the right. Anomalously originating OA is rare and occurs with right-side predominance. Correct diagnosis is necessary before or during cerebral angiography, especially when selective catheterization to the OA is required.

Persistent primitive olfactory artery (PPOA) is a relatively rare variation of the proximal anterior cerebral artery (ACA) that generally follows an extreme antero-inferior course and takes a hairpin turn. To our knowledge, incidence of PPOA has not been reported, so we researched cases in our institution records to determine incidence and investigated characteristic features of the condition on MR angiography.To isolate cases with PPOA, we retrospectively reviewed cranial magnetic resonance (MR) angiographic images of a total of 3,626 patients in our institution and collected similar images from cases with PPOA from our two affliated hospitals.We found 14 cases with PPOA (six men and eight women); 5 patients in our institution, representing an incidence of 0.14%, and 9 cases from our group hospitals. The location was on the right in six cases, left in seven, and bilateral in one. An aneurysm was found at the hairpin turn in one patient, and in another patient, the PPOA connected with the accessory middle cerebral artery (MCA) and not the distal ACA.In our institution, incidence of PPOA on MR angiography was 0.14%. We found no laterality in frequency and rare bilaterality, aneurysm at the point of the hairpin turn, and accessory MCA arising from the PPOA.