Hellenic journal of nuclear medicine最新文献

Objective: Myocardial perfusion imaging (MPI) can be challenging in some cases of multi vessel involvement. Our aim was to examine specific group of patients with diabetes mellitus (DM), who did not have significant reversible ischaemia diagnosed on perfusion study itself, and asses additional value of functional parameters obtained from gated acquisition and added information from coronary artery calcium score (CACS).

Subjects and methods: One hundred and seventy eight patients with a history of DM, with summed difference score (SDS)≤1, were included in the study. All patients underwent gated acquisition with recording of functional parameters and CACS evaluation. During the follow-up, cardiac events (CE) were recorded.

Results: During the median follow-up of 20.3 months there were 23 CE encountered. Optimal cut-off value for CACS to predict CE was found at 1427, higher values were significantly related to CE (P<0.001). Low stress left ventricular ejection fraction (LVEF) <45% and induced stress LVEF drop for 5% were also more frequent in CE group (P=0.001, P=0.008). Multivariable Cox analysis revealed low stress LVEF (P=0.001, HR=4.48, 95%CI 1.79-11.22), stress induced LVEF drop (P=0.017, HR 3.13, 95%CI 1.22-8.01) and high CACS (P<0.001, HR 10.52, 95%CI 4.32-25.63) as significant predictors of CE.

Conclusion: Low stress LVEF under 45%, post-stress LVEF drop for more than 5% and CACS more than or equal to 1427 are significant predictors of CE in patients with DM, who did not have reversible ischemia detected on MPI single photon emission computed tomography (SPECT).

Extensive tumor thrombus and simultaneous pulmonary metastasis in glioma patient is rare. Herein, we reported a 45-year-old woman with extensive tumor thrombus in sagittal sinus and sigmoid sinus with obvious enhancement on magnetic resonance imaging (MRI). Fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) showed extensive tumor thrombus in sagittal sinus, sigmoid sinus andinternal jugular vein, and simultaneous left hilar lymph node andpulmonary metastasis. Our case demonstrated the value of ¹⁸F-FDG PET/CT for correctly identifying tumor thrombus,detecting extent of tumor thrombus and distant metastasis in high grade glioma patients.

A 45-year-old man had right chest and back pain for 15+ days without any cause, each lasting 3-10 minutes, and sometimes it could radiate to the right shoulder. Chest computed tomography (CT) scan showed bony destruction in the dorsal segment of the 4^th rib on the right. Metastatic disease was suspected and for this reason, fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/CT was performed. The images demonstrated increased ¹⁸F-FDG activity in the dorsal segment of the 4^th rib on the right with osteolytic bony destruction. Postsurgical pathological examination showed aneosinophilic abscess (EA).

Objective: The aim of this study is to compare the activity amounts used in the standard activity approach with the activity amounts calculated with the dosimetric method for the ablation of post-operative differentiated thyroid cancer residual tissue.

Subjects and methods: Seventeen patients (mean age=47.5±8.4 years) were included in the study. Time-activity curves were created by measuring iodine-131 (¹³¹I) uptake values of residual tissue at 4^th, 24^th, 48^th and 96^th hours following oral administration of ¹³¹I. In a dosimetric approach, activity amounts exposing 300Gy to residual tissue were calculated using medicalinternal radiation dose (MIRD) formulation.

Results: Dosimetric calculation could not be made in 3 patients because there was not enough radioactive iodine uptake (RAIU) at the neck to calculate the radioactive iodine treatment (RAIT) dose. The lowest and highest activity amounts determined by dosimetric calculations were 259MBq and 10860MBq, respectively. Dose amounts for the proposed treatment were decreased in 8 and increased in 6 patients compared to the standard activity approach. Cumulative activity (CA) and total cumulative activity (TCA) levels were found to be high in 1 patient who could not achieve adequate ablation.

Conclusion: We recommend the dosimetric approach for ablation of residual postoperative thyroid tissue to find patients with high levels of CA and TCA levels to consider higher activity doses compared to risk stratification assessment.

Objective: Neurolymphomatosis (NL) is a rare but serious manifestation defined as invasion of peripheral nervous system by malignant lymphocytes. Thus, this study investigated fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) and clinicopathological characteristics of NL in lymphoma patients.

Subjects and methods: Clinicopathological and ¹⁸F-FDG PET/CT findings and treatment regimens were retrospectively investigated in 20 lymphoma patients with NL, and analyzed their correlation with progression-free survival (PFS) and overall survival (OS).

Results: These 20 lymphoma patients (11 males, 9 females; median age, 49 years) included 10 primary and 10 secondary NL patients. Non-Hodgkin's lymphoma (NHL) was noted in 19 patients, B-cell NHL was associated with 18 cases, and diffuse large B-cell lymphoma was the most common. Notably, 18 patients were aggressive lymphoma while 2 were indolent lymphoma. The affected neural structures included nerve roots (n=17), peripheral nerves (n=3), cranial nerves (n=3), and neural plexus (n=2). Fluorine-18-FDG was avid in all cases, and the median maximum standardized uptake value (SUVmax) of neural and all lesions was 12.2 (range, 3.3-25.6) and 15.0 (range, 4.4-34.2), respectively. The median PFS and OS of all patients were 9.3 and 14.3 months. The 12-month OS rate of 18 patients with aggressive lymphoma receiving intrathecal chemotherapy/autologous stem cell transplants (IT chem/ASCT) was significantly higher than who did not (64.8% vs 15.9%).

Conclusion: The majority of NL occurred in patients with aggressive lymphoma, of which B-cell NHL were the predominant subtypes. Fluorine-18-FDG PET/CT imaging of NL was mainly characterized by intense glucose accumulation alongside peripheral nerves, and IT chem/ASCT was suggested to improve the outcomes of NL.

Objective: This study was conducted to investigate the utility of standardized uptake value (SUV) derived from bone single photon emission tomography/computed tomography (SPECT/CT) for diagnosing bone metastasis.

Subjects and methods: One hundred forty-seven patients with malignant cancer (breast or prostate cancer), joint disorders, primary skeletal disease, or cartilaginous bone neoplasms who underwent skeletal quantitative SPECT/CT were retrospectively investigated. Acquired data were classified as normal fourth lumbar vertebra, skeletal degenerative changes, or bone metastasis. Receiver operating characteristic (ROC) curves were used to determine the optimum cut-off value for SUVmax to distinguish among these diagnoses.

Results: Mean SUVmax values for the normal L4 bone (n=101), skeletal degenerative changes (n=47) and bone metastasis (n=64) groups were 4.47±1.66 (range 1.01-11.25), 6.99±2.58 (2.21-14.6), and 25.4±15.7 (3.88-98.87), respectively. Compared to the other two groups, SUVmax for the bone metastasis group was significantly higher (P<0.001). In the normal bone group, sensitivity, specificity and accuracy for discriminating bone metastasis were 96.3%, 95.1%, and 95.7% respectively, with a best SUVmax cut-off value of 7.40. For the skeletal degenerative changes group sensitivity, specificity and accuracy were 87.5%, 93.6%, and 90.4% respectively, with a best SUVmax cut-off value of 11.26.

Conclusion: Quantitative bone SPECT/CT may be useful for bone metastasis diagnosis.

Objective: The aim of this study is to investigate the roles of pre- and post- treatment quantitative fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) parameters including maximum standardized uptake value (SUVmax), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) and their rate of change in predicting pathological complete response (pCR) in patients with local and locally advanced invasive breast cancer receiving neoadjuvant chemotherapy (NAC).

Subjects and methods: Ninety-eight patients who received NAC after being diagnosed with local and locally advanced invasive breast cancer between January 2017 and September 2021 were retrospectively included in our study. Molecular subtypes of all patients were determined. Maximum SUV, MTV, TLG, percent change in SUVmax (ΔSUVmax), ΔMTV, and ΔTLG obtained from PET/CT scans performed before and after NAC were calculated. The cut-off, AUC, sensitivity, and specificity values of these parameters in predicting pCR were calculated using receiver operating characteristic (ROC) curves.

Results: ΔTMTV (cut-off 94.01%, AUC: 0.846), ΔTTLG (cut-off 97.36%, AUC: 0.870), B2MTV (cut-off<1.75, AUC: 0.764), B2TLG (cut-off<2.11, AUC: 0.764), B2SUVmax (cut-off<1.58, AUC: 0.767), ΔBMTV (cut-off 93.67%, AUC: 0.851), ΔBTLG (cut-off 97.22%, AUC: 0.870), ΔBSUVmax (cut-off 84.99%, AUC: 0.846) calculated using ROC curves were found to significantly predict pCR with high sensitivity and specificity.

Conclusion: We concluded that metabolic and volumetric PET/CT parameters, the rates of their change, and metabolic response during NAC may be important variables in predicting pCR in patients with breast cancer.

Technetium-99m (^99mTc)-labeled pyrophosphate (PYP) and 3,3-diphosphono-1,2-propanodicarboxylic acid (DPD) are currently the most established imaging agents for the diagnosis of cardiac amyloidosis, being able to distinguish light chain (AL) from transthyretin (TTR) type of the disease. We present a pattern of increased uptake in all soft tissues, sparing the organs that are usually most affected.

A 52-year old woman with fever of unknown origin underwent fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography/computed tomography (PET/CT) scan for further evaluation. A clinical history of cervical cancer (CIS) operated 20 years ago was documented. Two foci in the right lobe of the slightly enlarged liver presented increased ¹⁸F-FDG uptake. Visceral brucellosis was diagnosed via blood culture. The patient received anti-brucella therapy and recovered rapidly, the liver lesions diminished on control CT.

Epstein-Barr virus-associated smooth muscle tumor (EBV-SMT) is an exceedingly rare neoplastic disease with a predisposition in immune-compromised individuals, especially in patients with prior transplantation, human immunodeficiency virus infection, or congenital immunodeficiency. Here, we present imaging findings of EBV-SMT in multiphasic contrast-enhanced computed tomography (CT) and fluorine-18-fluorodeoxyglucose (¹⁸F-FDG) positron emission tomography (PET)/CT in a two-and-a-half-year-old boy with prior heart transplantation.