Clinical Nuclear Medicine最新文献

Abstract: An 80-year-old patient with hepatocellular carcinoma (HCC) underwent an 18 F-FDG PET/CT scan owing to suspected lumbar metastasis identified via a CT scan performed during transarterial chemoembolization (TACE) 2 weeks earlier. The PET scan revealed segmental high uptake in the HCC and surrounding liver parenchyma, where lipiodol deposited during TACE had mostly washed out. The segmental uptake was attributed to TACE-induced inflammatory changes in the liver parenchyma around the HCC, confirmed by reduced uptake in a follow-up 18 F-FDG PET/CT scan 4 months later. This highlights the need to differentiate between inflammation and viable HCC in post-TACE 18 F-FDG PET/CT evaluations.

Abstract: Positivity of follicular dendritic cell tumor in somatostatin receptor imaging is rare. A 68-year-old woman underwent ultrasound in health examination. The results showed abnormal echoes in the pancreatic head region, suggestive of a neuroendocrine tumor of the pancreatic head. 18 F-AlF-NOTA-octreotide PET/CT was performed for staging. 18 F-AlF-NOTA-octreotide PET/CT revealed an irregular mass between the caudate lobe of the liver and the pancreatic head with heterogeneously increased uptake, which was later confirmed as follicular dendritic cell tumor by pathological examination.

Abstract: Synovial sarcoma is a rare malignancy of mesenchymal origin, known for its propensity for metastasis and challenging early diagnosis, primarily affecting adolescents and young adults. This case report illustrates the utility of 18 F-fibroblast activation protein inhibitor PET/CT in an 18-year-old woman with synovial sarcoma primarily located in the left calf and metastases in the left thoracic cavity.

Abstract: A 51-year-old man with severe multifactorial neurocognitive disorders subsequent to delirium, benzodiazepine withdrawal, and preexisting psychiatric illness was referred for 18 F-FDG PET/CT brain imaging in order to rule out an underlying neurodegenerative cause of the symptoms, particularly frontotemporal lobar degeneration. Imaging was impaired by severe motion artifacts, leading to a false-positive result. However, utilizing retrospective data-driven motion correction facilitated a change in diagnosis, ruling out the presence of neurodegenerative disease. The implementation of motion correction of the 18 F-FDG PET dataset proved crucial for the patient, as the exclusion of frontotemporal lobar degeneration formed the basis for continuing psychiatric and psychotherapeutic treatment.

Abstract: Long-term subcutaneous insulin injection causes histopathological changes, such as insulin amyloidosis resulting in poor glycemic control, at the insulin injection site. Insulin amyloidosis often leads to the formation of a nodule called the "insulin ball." An insulin ball has not yet been documented on 99m Tc-PYP scintigraphy. Hereby, we describe the case of a 74-year-old man with insulin-requiring diabetes who developed heart failure with preserved ejection fraction due to new-onset atrial fibrillation. 99m Tc-PYP scintigraphy for cardiac amyloidosis screening showed no tracer uptake in the myocardium but did show uptake in the insulin ball suspected by CT and MRI scans.

Abstract: Accidental intra-arterial injections of radiotracers are rare events resulting in a specific imaging pattern, described as "hot-forearm," "hot-hand," "glove-phenomenon," or "glove-like pattern." We present a case 68 Ga-DOTATATE total-body PET/CT for restaging of a neuroendocrine tumor, where intra-arterial misinjection resulted in a glove phenomenon. Since patients may present with minimal symptoms, like in this case, and PET findings may only be seen at the distal upper extremity (placed above the head), these accidental injections may be more frequently detected with total-body PET/CT due to the longer field-of-view. Radiologists and technologists should be aware of this possibility to avoid accidental misinjections.

Abstract: Trigeminal neuralgia (TN) is characterized by excruciating facial pain usually caused by neurovascular compression of the trigeminal nerve roots. TN can be treated medically or invasively. Microvascular decompression is the procedure of choice and usually results in complete symptom relief. During surgical decompression, Teflon can be placed between the offending vessel and the nerve root entry zone. In some cases, chronic Teflon-related inflammation can cause recurrent TN, which might lead to additional surgical intervention. We present imaging and histopathological correlation of a patient presenting with intractable recurrent TN approximately 2 years after microvascular decompression with Teflon implant.

Abstract: Solitary fibrous tumors (SFTs) are fibroblast tumors that occur mainly in the pleura. Hepatic SFT with skeleton metastases was rarely documented. In this case, we report the contrast-enhanced CT, 18 F-FDG, and 68 Ga-FAPI-46 PET/CT findings of a rare hepatic SFT with bone metastases. 68 Ga-FAPI-46 PET/CT showed much higher tumor-to-background contrast of hepatic tumors and revealed more metastatic bone lesions than 18 F-FDG PET/CT. This case demonstrated the superiority of 68 Ga-FAPI-46 PET/CT over 18 F-FDG for identifying metastatic lesions in malignant SFTs. This observation may add information on the benefit of FAPI PET/CT in SFT staging.

Abstract: A 12-year-old girl with no previous comorbidities presented with a left gluteal swelling. 18 F-FDG PET/CT demonstrated heterogenous, moderate hypermetabolism localizing to a very large pelvic soft tissue mass with extension through the left greater sciatic notch into the left deep gluteal space. Core biopsy of the mass revealed INI1-negative myoepithelial carcinoma. Here we report the molecular imaging findings in an extremely rare pediatric case of INI1-negative, soft tissue myoepithelial carcinoma.

Abstract: Benign metastasizing leiomyoma (BML) is a rare disease associated with pelvic leiomyoma. We report 18 F-FDG and 68 Ga-FAPI PET/CT findings in a 51-year-old woman with multiple BMLs. The mass in the abdominopelvic cavity and other metastatic lesions showed highly increased 68 Ga-FAPI uptake, whereas uptake of 18 F-FDG in those lesions was low. Our report demonstrates that 68 Ga-FAPI PET/CT showed a different result in detecting BML to 18 F-FDG PET/CT, and 68 Ga-FAPI PET/CT may be a promising method for whole-body evaluate metastases.