Clinical Nuclear Medicine最新文献

A 53-year-old man presented with right upper abdominal pain for more than 3 weeks without an apparent cause. Multiple sequences of MR imaging detected multiple liver nodules with irregular peripheral enhancement. 18 F-FDG and 68 Ga-FAPI PET showed multiple elevated tracer uptake, which mimicked multiple liver metastases of unknown primary focus. Finally, the pathology of ultrasound-guided biopsy confirmed the diagnosis of hepatic eosinophilic granuloma (HEG).

Gilal fibrillary acidic protein (GFAP) meningomyelitis is a rare autoimmune inflammatory disorder of the central nervous system, typically presenting with subacute encephalopathy, ataxia, optic neuritis, and cerebrospinal fluid (CSF) pleocytosis. It is characterized by the presence of GFAP-specific autoantibodies, which target astrocytes and cause widespread neuroinflammation. 18 F-FDG PET/CT plays a critical role in the early diagnosis of autoimmune encephalitides, particularly in cases where conventional MRI findings may be subtle or nonspecific. Here, we present a case of 21-year-old woman who presented with early morning occipital headache with fever, followed by progressive drowsiness and acute urinary retention. On clinical examination, meningeal signs were positive. MRI brain was suggestive of leptomeningeal enhancement involving the brain and spinal cord, and 18 F-FDG PET/CT was done for further evaluation.

Technetium-99m Technegas SPECT/CT is a promising tool for the localization of postoperative air leaks in thoracic surgery patients. We report a case of successful leak detection in a mechanically ventilated patient following thoracoscopic surgery and revision. Radioventilation was performed by connecting the TechnegasPlus (Cyclomedica Pty Ltd.) generator's administration set to the patient's endotracheal tube and gently inflating the lungs with a disposable respirator through the generator's assist valve. Intense pleural Technegas accumulation was observed as a correlate of the air leak. Characteristic changes of ventilation distribution secondary to mechanical ventilation are discussed.

[ 18 F]FDG PET/CT is widely used in the diagnosis and treatment monitoring of lung cancer, yet its ability to differentiate histologic heterogeneity remains limited. In this case, a 75-year-old man presented with a large pulmonary mass adjacent to a small satellite lesion. Bronchoscopic biopsy of the main lesion revealed small-cell lung cancer (SCLC). After first-line chemotherapy, the primary lesion showed partial response, while the smaller nodule remained stable. Posttreatment [ 18 F]FDG and [ 68 Ga]Ga-DOTA-3P-TATE-RGD PET/CT demonstrated divergent uptake patterns. Rebiopsy of the nodule with discordant tracer uptake confirmed squamous cell carcinoma, indicating synchronous double primary lung cancers. The dual-targeted tracer PET/CT guided precise biopsy and individualized therapy.

DOTA-IBA is a novel bone-targeting precursor for metastatic bone disease. It was radiolabeled with 225Ac to generate the alpha-emitting therapeutic agent 225Ac-DOTA-IBA. In this report, a 70-year-old man with pulmonary sarcomatoid carcinoma and extensive skeletal metastases was treated upfront with 2 cycles of 225Ac-DOTA-IBA. The patient showed excellent symptomatic and radiological response. In addition, no adverse effects were observed in the patient.

Primary tracheal lymphoma is very rare, accounting for <1% of all primary tracheal tumors. We describe FDG PET/CT findings in a case of primary anaplastic lymphoma kinase (ALK)-negative anaplastic large cell lymphoma of the trachea. The tumor was located in the lower tracheal wall and showed intense activity. A follow-up FDG PET/CT after 8 cycles of chemotherapy showed complete resolution of the tumor.

Purpose: Kidney transplantation is the treatment of choice for end-stage kidney disease, but predicting short-term and long-term outcomes remains challenging. Noninvasive, widely available tools for early risk stratification are lacking. This study evaluated whether the tubular extraction rate (TER) of Tc-99m-MAG3 measured by renal scintigraphy can predict transplant outcomes.

Methods: In this prospective observational study, 488 kidney transplant recipients (2012-2022) underwent standardized Tc-99m-MAG3 scintigraphy on postoperative day 6 to quantify TER. Patients were stratified into quartiles. Primary short-term endpoints were delayed graft function (DGF) and length of hospital stay; the primary long-term endpoint was a composite of graft loss or death. Associations were assessed using multivariable logistic regression, generalized linear models, and Cox regression.

Results: Lower TER was significantly associated with older donor and recipient age, longer ischemia times, and higher DGF risk [adjusted OR 9.45 (95% CI: 4.31-20.72), lowest vs. highest quartile]. Low TER was linked to more dialysis sessions and longer hospitalization. During a median follow-up of 8.4 years, low TER was independently associated with increased risk of biopsy-proven rejection (HR: 4.23; 95% CI: 1.05-17.13), graft failure or death (HR: 3.87; 95% CI: 1.67-8.97). eGFR values over time were consistently higher in patients with higher TER values.

Conclusions: The tubular extraction rate derived from MAG3 scintigraphy is a strong and independent predictor of both short-term and long-term outcomes after kidney transplantation. As a noninvasive and widely available diagnostic tool, it may facilitate early identification of high-risk transplant recipients and support personalized post-transplant care strategies.

A 72-year-old man underwent 18 F-DCFPyL PSMA PET/CT imaging for the localization of biochemical recurrence (BCR) of prostate cancer. The scan revealed no definite findings, with only a vague uptake of uncertain significance in the bladder neck region. An additional PET/CT scan using a 64 Cu-labeled trimeric PSMA ligand demonstrated astonishing distinct uptake in the former prostate bed, unequivocally confirming the presence of a small local recurrence and allowing for targeted local therapy. This intriguing case highlights the potential of PET/CT using 64 Cu-labeled trimeric PSMA ligands, especially when conventional PSMA PET/CT scans yield ambiguous results.

A 77-year-old woman with mild cognitive impairment was referred to 18F-florbetapir positron emission tomography (PET) to assess the indication of a disease-modifying drug against Alzheimer disease. PET images showed no uptake in the brain and only slight uptake in the sinus veins. In an automated injector, almost all the radioactivity was trapped in an air-vent filter, which is usually used for FDG injections and is made of mixed cellulose ester. After injection using other types of filters not made of mixed cellulose ester, 18F-florbetapir PET imaging was successful. The filter made of mixed cellulose ester should never be used for 18F-florbetapir injection.

Primary leptomeningeal melanomatosis is a rare and aggressive variant of primary central nervous system melanoma. Diagnosis is often challenging due to nonspecific radiologic features. We hereby report the 18F-FDG PET/CT and MRI findings in a case of primary leptomeningeal melanomatosis in a 47-year-old woman with a previously unidentified diastematomyelia. Spinal MRI showed diffuse abnormal signal. 18F-FDG PET/CT showed hypermetabolism most notably in the lumbar and caudal portion of the spinal cord, which was helpful to identify an appropriate site for biopsy.