Mimicker of Osteoblastic Skeletal Metastasis on 18 F-FDG PET/CT Scan in a Case of Primary Mediastinal Germ Cell Tumor.

ABSTRACT: Primary mediastinal germ cell tumors are uncommon tumors, of which the nonseminomatous type is more likely to metastasize than the seminomatous type. Primary mediastinal germ cell tumors may also present with superior vena cava obstruction. Here, we present this case of primary mediastinal germ cell tumor with superior vena cava obstruction causing dilatation of collaterals in dorsal intravertebral venous plexus, which strongly mimics sclerotic skeletal lesions/metastasis on a Contrast-enhanced CT scan and also appears FDG avid on PET scan. Herein, we can differentiate the two by just a simple review of plain CT scan image.

Development of a Peri-renal Urinoma in a Follow-up Patient with History Posttraumatic Peri-nephric Hematoma: Role of Renal Scintigraphy.

A 7-year-old male with a history of blunt trauma to the abdomen and diagnosis of perinephric hematoma in contrast-enhanced computed tomography (CT) presented with increasing peri-nephric collection (after ~1.5 months) in the serial ultrasound examinations. The patient was referred to the department of nuclear medicine for the assessment of this collection as well as renal function. In 99mTc-diethylenetriamine pentaacetate renal scintigraphy, progressively increasing radiotracer activity was noted inferolaterally to the left kidney, separated from the same by a photopenic area. Single-photon emission computed tomography/CT revealed a peri-nephric urinoma in relation to the previously diagnosed hematoma at the lower pole; which was communicating with the pelvi-calyceal system (PCS). Not only did the renal scintigraphy aid in the diagnosis of urinoma but it was also able to show that it was communicating freely with the PCS and that the rest of the renal parenchyma was functioning adequately. This multi-faceted assessment in a single investigation allowed clinicians to opt for the conservative management despite the increasing size of urinoma in the early follow-up.

Simultaneous Detection of Biliary Injury and Vascular Infarct using 99mTc-HIDA Scintigraphy in a Patient with Trauma.

A 45-year-old male with a history of trauma was referred to the department of nuclear medicine to identify site of a biliary leak, which could not be identified in ultrasound and exploratory laparotomy. Contrast-enhanced computed tomography (CT) was able to identify lacerations in the right lobe of the liver, but the extent of injury to the biliary pathways and vessels was unclear. 99mTc-HIDA scintigraphy with single-photon emission CT/CT was not only able to identify the site of leak but also the extent of infarcted area.

Splenic Uptake in 99 mTc-Methylene Di-Phosphonate Scan in a Pediatric Patient with Acute Lymphocytic Leukemia.

An 12-year-old boy with relapse of acute lymphocytic leukemia and suspected skeletal involvement underwent mTc-Methylene Di-Phosphonate skeletal scintigraphy, which revealed a lytic "cold" lesion in the pelvis and diffuse splenic uptake. There was no active splenic infiltration in cross-sectional imaging. However, the patient had a history of multiple blood transfusions, which is a rare cause for diffuse splenic uptake.