Isolated Rectal Metastases from Locally Advanced Carcinoma Prostate Detected by 18 F-PSMA-1007 PET/CT.

Rectal involvement by prostate carcinoma is rare and isolated rectal metastases are even rarer with only a few cases having been reported in the literature. In our knowledge, no case of isolated rectal metastases diagnosed on prostate specific membrane antigen positron emission tomography/computed tomography has been reported to date. We present a case of a 66-year-old patient who presented with rectal bleeding and passage of urine from anal region and was diagnosed with carcinoma prostate infiltrating the rectum along with solitary rectal metastases.

Non-contrast MR angiography versus contrast enhanced MR angiography for detection of renal artery stenosis: a comparative analysis in 400 renal arteries.

PURPOSE: In this study, we compared non-contrast MR angiography (NC-MRA) with conventional 3D contrast-enhanced MRA (CE-MRA) in patients suspected to have renal artery stenosis (RAS). METHODS: From March 2014 to March 2020, patients who were evaluated for RAS and had a glomerular filtration rate > 30 ml/min/1.73 m2 underwent MR imaging on a 3T MR Scanner (Signa Hdxt General Electrics, Milwaukee, USA) using a Torso PA coil. The NC-MRA sequence was performed using a 3D fat-suppressed inflow inversion recovery balanced steady state free precession (SSFP) sequence (Inhance 3D Inflow IR, GE Medical) whereas the CE-MRA sequence was a 3D fast spoiled gradient echo (FSPGR). Overall quality of images was rated 1 to 4. Stenosis was reported as grade 1 (Normal), 2 (< 50% narrowing), 3 (> 50% narrowing) and 4 (Total occlusion). Grade 3 and 4 were considered haemodynamically significant. RESULTS: During the study period, 201 patients were enrolled (400 renal arteries). For hemodynamically significant (grade 3/4) stenosis, NC-MRA correctly diagnosed 72 patients (95 arteries) while in 2 patients (2 arteries), NC-MRA underdiagnosed the stenosis as grade 2 (these were found to have grade 3 stenosis on CE-MRA). The kappa value of agreement between NC-MRA and CE-MRA for detection of RAS showing excellent agreement (p < 0.001). CONCLUSION: In one of the largest series of patients so far, we found that NC-MRA is a viable alternative to CE-MRA for detection of RAS, highly correlating with CE-MRA for grade of stenosis and with additional advantage of lack of gadolinium based contrast agents toxicity.

Gallbladder Visualization on Tc-99m-labeled Red Cell Scintigraphy: A Rare Finding with an Emphasis on Role of Single-photon Emission Computed Tomography/Computed Tomography.

Tc-99m labeled red blood cell (RBC) scintigraphy is one of the most sensitive tests to diagnose occult gastrointestinal (GI) bleed. Visualization of gallbladder is a rare finding in this study. Most of the previously reported cases with similar false-positive finding were associated chronic renal failure, anemia, and received multiple blood transfusions. Thus, while interpreting GI bleed scan, a thorough clinical history is of utmost importance to avoid any false-positive findings. Here, we report a case of gallbladder visualization in 99mTc-RBC scintigraphy confirmed by single-photon emission computed tomography/computed tomography in a patient with chronic renal failure and anemia with failed renal transplant within 3 months.