Trapping of 18F-Fluciclovine (FACBC) in Superior Sagittal Sinus.

As F-fluciclovine (FACBC) becomes more popular, new incidental findings are discovered. We present here a case of a 71-year-old man with prostate cancer in whom an FACBC PET/CT showed uptake in the superior sagittal sinus, which was found to be simply due to a dilated superior sagittal sinus on subsequent MRI. Accumulation in the superior sagittal sinus is a variant that interpreters of FACBC PET/CT should be aware of.

Subsequent experience in hybrid PET-MRI for evaluation of refractory focal onset epilepsy.

PURPOSE: Epilepsy surgery is the most successful method of treating medically unresponsive epilepsy, but carries a risk of morbidity. PET/MR is an emerging technique that increases detection of focal lesions whose resection may result in symptom remission. METHODS: Retrospective review of 74 focal epilepsy patients over a period of 3 years who had a PET/MR was performed following IRB permission and informed consent. 27 patients underwent surgery or RNS (responsive neurostimulator) placement. RESULTS: Hybrid PET-MR identified new anatomic or functional lesions in 10 patients not identified with standalone 3 T MR. Of the 27 patients who underwent focal surgery (19) or RNS placement (8), 24 showed improvement (Engel's I-III), 2 did not (Engel's IV), and one had an RNS explanted due to infection. MR and PET were read by 2 separate neuroradiologists and nuclear medicine physicians, respectively. Modalities were evaluated in terms of ability to detect the correct lobe and side for a focal lesion whose resection improved symptoms. Prior standalone MR exhibited 71-77% sensitivity and 0% specificity (as there were only 2 nonresponders), MR associated with PET/MR had 68-71% sensitivity and 0-50% specificity (depending on whether a lesion was seen on one of the nonresponders), and PET had 68-71% sensitivity and 25-33% specificity. Using either PET or MR to identify a focal lesion, PET/MR had sensitivity of 78-82% and specificity 0-50%. CONCLUSIONS: PET-MR provides additional sensitivity when used as two combined modalities for detecting possible epileptic foci.

Quantitative accuracy of positron emission tomography/magnetic resonance and positron emission tomography/computed tomography for cervical cancer.

With the spread of positron emission tomography/magnetic resonance (PET/MR), the question of comparability of studies becomes important. We aim to determine whether PET/MR and PET/computed tomography (PET/CT) are comparable for the case of cervical cancer. Fifteen cervical cancer patients identified by either a radiation oncologist or an oncologic surgeon had both PET/MR and PET/CT performed for initial staging within 3 weeks. We then compared the results both quantitatively (measuring standardized uptake values [SUVs] on visible lesions) as well as qualitatively (having radiologists and nuclear medicine physicians interprets the results). While interpretations between PET/MR and PET/CT varied in many cases, SUVs of primary lesions were similar to within 25% in all but one case, and correlation coefficient was 0.92. Maximum SUV ranged between 4.9 and 25.2 for PET-MR and between 5.8 and 30.4 for PET-CT for primary tumors and between 1.5 and 18.8 for PET-MR and between 1.8 and 20.8 for PET-CT for nodes. However, clinical reads often varied significantly between PET/MR and PET/CT. This suggests that SUV is similar on PET/MR and PET/CT although the differing anatomic modalities available for correlation may make the difference in terms of qualitative interpretation.