12 research outputs found
The added diagnostic value of dynamic contrast-enhanced MRI at 3.0 T in nonpalpable breast lesions.
To investigate the added diagnostic value of 3.0 Tesla breast MRI over conventional breast imaging in the diagnosis of in situ and invasive breast cancer and to explore the role of routine versus expert reading.We evaluated MRI scans of patients with nonpalpable BI-RADS 3-5 lesions who underwent dynamic contrast-enhanced 3.0 Tesla breast MRI. Initially, MRI scans were read by radiologists in a routine clinical setting. All histologically confirmed index lesions were re-evaluated by two dedicated breast radiologists. Sensitivity and specificity for the three MRI readings were determined, and the diagnostic value of breast MRI in addition to conventional imaging was assessed. Interobserver reliability between the three readings was evaluated.MRI examinations of 207 patients were analyzed. Seventy-eight of 207 (37.7%) patients had a malignant lesion, of which 33 (42.3%) patients had pure DCIS and 45 (57.7%) invasive breast cancer. Sensitivity of breast MRI was 66.7% during routine, and 89.3% and 94.7% during expert reading. Specificity was 77.5% in the routine setting, and 61.0% and 33.3% during expert reading. In the routine setting, MRI provided additional diagnostic information over clinical information and conventional imaging, as the Area Under the ROC Curve increased from 0.76 to 0.81. Expert MRI reading was associated with a stronger improvement of the AUC to 0.87. Interobserver reliability between the three MRI readings was fair and moderate.3.0 T breast MRI of nonpalpable breast lesions is of added diagnostic value for the diagnosis of in situ and invasive breast cancer
Enantioselective Syntheses of Furan Atropisomers by an Oxidative Central-to-Axial Chirality Conversion Strategy
For
the first time, enantiomerically enriched atropoisomeric furans
have been accessed using a central-to-axial chirality conversion strategy.
Hence, oxidation of the enantioenriched dihydrofuran precursors gave
rise to axially chiral furans with high enantiopurities accounting
from excellent conversion percentages (cp) in most cases
ROC analysis shows an AUC of 0.76 for the model with clinical characteristics and conventional imaging, which is displayed as the green, dashed line in the three graphs (a-c).
<p>The red, solid lines show the AUC's for the models after addition of MRI reading. The model for routine reading has an AUC of 0.81 (a), both models with expert MRI reading have an AUC of 0.87 (b-c).</p
Craniocaudal (a) and mediolateral oblique (b) mammogram of a 40 year old, asymptomatic woman underwent mammography during follow-up after right-sided breast cancer, for which she underwent mastectomy.
<p>Mammography showed BI-RADS 4 microcalcifications in the lateral upper quadrant of the left breast. Ultrasound imaging was unremarkable (BI-RADS 1). During routine MRI reading, a BI-RADS 1 classification was assigned. Expert reader 1 reported an area of non-mass-like enhancement with a diffuse distribution, heterogeneous internal enhancement and classified MR imaging as BI-RADS 4. In addition, expert reader 2 described an area of non-mass-like enhancement with a segmental distribution and clumped internal enhancement, and reported a BI-RADS 4. Kinetics showed a rapid initial rise and a plateau stage during the delayed phase. Figure 2 shows the dynamic contrast-enhanced MRI (c) and the MR image imported in the CAD software (d). The color-coded overlay indicates the type of enhancement after contrast injection in the late phase. Yellow and blue illustrate a plateau- and persistent- enhancement curve, respectively. Stereotactic biopsy showed normal breast tissue with minor fibrocystic changes and the extensive presence of microcalcifications.</p
Craniocaudal (a) and mediolateral oblique (b) mammogram of a 52 year old patient with BI-RADS 5 microcalcifications in the left lateral upper quadrant.
<p>Ultrasound imaging was unremarkable (BI-RADS 1). During routine reading, the MRI examination was classified as BI-RADS 4. Both expert reader 1 and 2 classified the lesion as an area of non-mass like enhancement with clumped internal enhancement and a segmental distribution. Kinetics showed a rapid initial rise and a plateau stage during the delayed phase. A BI-RADS 4 and 5 classification was given by expert reader 1 and 2, respectively. Figure 1 shows the dynamic contrast-enhanced MRI (c) and the MR image imported in the CAD software (d). The color-coded overlay indicates the type of enhancement after contrast injection in the late phase. Red, yellow and blue illustrate a washout-, plateau- and persistent- enhancement curve, respectively. Stereotactic biopsy and surgery both showed DCIS without an invasive component.</p
BI-RADS MRI classifications for routine and expert MRI reading.
<p>BI-RADS MRI classifications for routine and expert MRI reading.</p
ROC analysis shows an AUC of 0.76 for the model with clinical characteristics and conventional imaging, which is displayed as the green, dashed line in the three graphs (a-c).
<p>The red, solid lines show the AUC's for the models after addition of MRI reading. The model for routine reading has an AUC of 0.81 (a), both models with expert MRI reading have an AUC of 0.87 (b-c).</p
Baseline table presenting clinical patient characteristics and features on mammography and ultrasound for the 207 index lesions.
<p>*independent sample T-test, ∧chi-square test, <sup>&</sup>Fisher's exact test</p>a<p>occult or benign lesion on mammography (BI-RADS 1 or 2), classified as BI-RADS 3, 4 or 5 on ultrasound.</p>b<p>cystic lesions, hypoechoic areas not otherwise specified, and areas of architectural distortion.</p
Sensitivity and specificity for routine and expert reading of 3.0 T breast MRI.
<p>Sensitivity and specificity for routine and expert reading of 3.0 T breast MRI.</p
The interobserver reliability (κ statistics) and agreement (proportion of agreement) for BI-RADS MRI classifications.
<p>The interobserver reliability (κ statistics) and agreement (proportion of agreement) for BI-RADS MRI classifications.</p
