Background and Purpose-The middle cerebral artery (MCA) "dot" sign consists of hyperdensity of an arterial structure, seen as a dot in the sylvian fissure. The MCA dot sign has been proposed to indicate thrombosis of M2 or M3 MCA branches, analogous to the hyperdense middle cerebral artery (HMCA) sign indicating M1 thrombosis. The MCA dot sign has not been validated previously against the gold standard of conventional cerebral angiography. Methods-Noncontrast CT scans and immediately subsequent cerebral angiograms from 54 acute stroke patients within 8hours of symptom onset were analyzed. CT films were inspected for the MCA dot sign and HMCA sign. Vascular findings on CT were compared with findings at angiography. Results-Mean patient age was 71 years; median National Institutes of Health Stroke Scale score was 16.5. Mean time from symptom onset to CT was 125 minutes, and that from CT to angiography was 117 minutes. All patients had arterial occlusion at angiography. Of the anterior circulation occlusions, M1 occlusions were noted in 28 patients, isolated M2 in 15, and isolated M3 in 4. One definite MCA dot sign was observed in 16.7% of patients, and an HMCA sign was observed in 13.9%. MCA dot sign performance in predicting the presence of M2 or M3 clot at angiography was as follows: sensitivity 38%, specificity 100%, positive predictive value 100%, negative predictive value 68%, and overall accuracy 73%. Conclusions-The MCA dot sign is a highly specific and moderately sensitive indicator of acute thrombus in the M2/M3MCA branches, as validated by catheter angiography. The MCA dot sign is a useful additional acute stroke CT marker.

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Background Noninvasive measurement of placental blood flow is the major technical challenge for predicting ischemic placenta (IPD). Pseudocontinuous arterial spin labeling (pCASL) MRI was recently shown to be promising, but the potential value in predicting the subsequence development of IPD is not known. Purpose To derive global and regional placental blood flow parameters from longitudinal measurements of pCASL MRI and to assess the associations between perfusion‐related parameters and IPD. Study Type Prospective. Population Eighty‐four women completed two pCASL MRI scans (first; 14–18 weeks and second; 19–24 weeks) from prospectively recruited 118 subjects. A total of 69 subjects were included for the analysis, of which 15 subjects developed IPD. Field Strength/Sequence 3T/T2‐weighted half‐Fourier single‐shot turbo spin‐echo (HASTE) and pCASL. Assessment Four perfusion‐related parameters in the placenta were derived: placenta volume, placental blood flow (PBF), high PBF (hPBF), and relative hPBF. The longitudinal changes of the parameters and their association with IPD were tested after being normalizing to the 16th and 20th weeks of gestation. Statistical Tests Comparisons between two gestational ages within subjects were performed using the paired Wilcoxon tests, and comparisons between normal and IPD groups were performed using the unpaired Wilcoxon tests. Results The difference between the first and second MRI scans was statistically significant for volume (156.6 cm3 vs. 269.7 cm3, P < 0.001) and PBF (104.9 ml/100g/min vs. 111.3 ml/100g/min, P = 0.02) for normal subjects, indicating an increase in pregnancy with advancing gestation. Of the parameters tested, the difference between the normal and IPD subjects was most pronounced in hPBF (278.1 ml/100g/min vs. 180.7 ml/100g/min, P < 0.001) and relative hPBF (259.1% vs. 183.2%, P < 0.001) at 16 weeks. Data Conclusion The high perfusion‐related image parameters for IPD were significantly decreased from normal pregnancy at 14–18 weeks of gestation. Level of Evidence 2 Technical Efficacy Stage 1 J. Magn. Reson. Imaging 2020;51:1247–1257.

2 Technical Efficacy: Stage 1 J. Magn. Reson. Imaging 2018.

Our findings suggest a significant role for FDG-PET in patients with suspected MTC recurrence, with sensitivity of 85.7% and specificity of 83.3% for disease detection. FDG-PET provides additional information in a significant fraction of cases (54%) and could be used for restaging of patients with MTC and elevated levels of biomarkers (calcitonin). Additional studies are necessary to further evaluate the role of FDG-PET in MTC.

Primary vulvar and vaginal cancers are rare female genital tract malignancies which are staged using the 2009 International Federation of Gynecology and Obstetrics (FIGO) staging. These cancers account for approximately 2,700 deaths annually in the USA. The most common histologic subtype of both vulvar and vaginal cancers is squamous cell carcinoma, with an increasing role of the human papillomavirus (HPV) in a significant number of these tumors. Lymph node involvement is the hallmark of FIGO stage 3 vulvar cancer while pelvic sidewall involvement is the hallmark of FIGO stage 3 vaginal cancer. Imaging techniques include computed tomography (CT), positron emission tomography (PET)-CT, magnetic resonance imaging (MRI), and PET-MRI. MRI is the imaging modality of choice for preoperative clinical staging of nodal and metastatic involvement while PET-CT is helpful with assessing response to neoadjuvant treatment and for guiding patient management. Determining the pretreatment extent of disease has become more important due to modern tailored operative approaches and use of neoadjuvant chemoradiation therapy to reduce surgical morbidity. Moreover, imaging is used to determine the full extent of disease for radiation planning and for evaluating treatment response. Understanding the relevant anatomy of the vulva and vaginal regions and the associated lymphatic pathways is helpful to recognize the potential routes of spread and to correctly identify the appropriate FIGO stage. The purpose of this article is to review the clinical features, pathology, and current treatment strategies for vulvar and vaginal malignancies and to identify multimodality diagnostic imaging features of these gynecologic cancers, in conjunction with its respective 2009 FIGO staging system guidelines.

The pathologically determined degree of necrosis postneoadjuvant chemotherapy was concordant with PET-assessed EORTC classification of response in 57.1% of the cases. However, a significant number of patients had discrepancies, which may be in part explained by chemotherapy-induced inflammation. The latter should be considered during post-therapy PET interpretation in OSTS.

As expected, BMRI is more sensitive than PET/CT in the detection of breast lesions. However, PET/CT as a whole-body examination changed the management of disease by detection of distant lesions in 6 of the 21 patients. Our study suggests that 18F FDG PET/CT and BMRI should be considered as complimentary imaging tools in the pre- and postoperative work-up of patients diagnosed with breast cancer.