[The applicability of 123I-FP-CIT SPECT dopamine transporter imaging in clinical practice]. / A 123I-FP-CIT SPECT dopamin transzporter képalkotás jelentosége a klinikai gyakorlatban.

The 123I-FP-CIT dopamine transporter SPECT imaging is a sensitive method to assess functional dopaminergic neuron terminals in the striatum. The method has also been available in Hungary for years. There are two main indications: (i) to help differentiate essential tremor from clinically uncertain Parkinsonism, including patients with early symptoms and (ii) to help differentiate dementia with Lewy bodies from Alzheimer's disease. The aim of this paper is to review 123I-FP-CIT SPECT imaging based on international data/guidelines and our own experiences, thereby assisting nuclear medicine practitioners and neurologists.

[The role of positron emission tomography (PET) in tumor diagnostics and therapy monitoring]. / A pozitron emissziós tomográfia (PET) helye a tumordiagnosztikában és a terápia követésében.

Positron emission tomography (PET) is a medical imaging method belonging to the realm of nuclear medicine. It has been a clinical research tool since the sixties but during the late nineties it became widely utilized in clinical practice too. PET technique requires special radioactive isotopes, which may be generated only in particle accelerators (cyclotrons) and their transport is limited owing to the short physical half-life. PET/CT was born from the combination of PET and CT (computer tomography). The first combined PET/CT scanner began to operate in 1998 and the method has been used in clinical practice since 2001. It is a hybrid (multi-modality) medical imaging equipment which can provide anatomical, morphologic (CT) and functional, metabolic information (PET) simultaneously. PET/CT imaging has gained clinical acceptance mainly in oncology - owing to the attributes of the most frequently used PET tracer, fluoro-deoxy glucose (FDG) - and in a lesser extent in neuropsychiatry and cardiology. The authors in this paper review the basics and key indications of the method, the wider used radiofarmacons, including potential neurological and psychiatric applications, and the possible causes of false positivity and false negativity.

The impact of post-radioiodine therapy SPECT/CT on early risk stratification in differentiated thyroid cancer; a bi-institutional study.

OBJECTIVE: SPECT/CT has numerous advantages over planar and traditional SPECT images. The aim of this study was to evaluate the role of post-radioiodine therapy SPECT/CT of patients with differentiated thyroid cancer (DTC) in early risk classification and in prediction of late prognosis. PATIENTS AND METHODS: 323 consecutive patients were investigated after their first radioiodine treatment (1100-3700 MBq). Both whole body scan and SPECT/CT images of the head, neck, chest and abdomen regions were taken 4-6 days after radioiodine therapy. Patients were re-evaluated 9-12 months later as well as at the end of follow up (median 37 months). RESULTS: Post-radioiodine therapy SPECT/CT showed metastases in 22% of patients. Lymph node, lung and bone metastases were detected in 61, 13 and 5 patients, respectively, resulting in early reclassification of 115 cases (36%). No evidence of disease was found in 251 cases at 9-12 months after radioiodine treatment and 269 patients at the end of follow-up. To predict residual disease at the end of follow-up, the sensitivities, specificities and diagnostic accuracies of the current risk classification systems and SPECT/CT were: ATA: 77%, 47% and 53%; ETA: 70%, 62% and 64%; SPECT/CT: 61%, 88% and 83%, respectively. There was no difference between cohorts of the two institutions when data were analyzed separately. CONCLUSIONS: Based on our bi-institutional experience, the accuracy of post-radioiodine SPECT/CT outweighs that of the currently used ATA and ETA risk classification systems in the prediction of long-term outcome of DTC.

Validation of an automated morphological MRI-based (123)I-FP-CIT SPECT evaluation method.

INTRODUCTION: Dopamine transporter imaging with (123)I-FP-CIT single photon emission computed tomography (SPECT) is helpful for the differential diagnosis between Parkinsonian syndrome (PS) and essential tremor (ET). Although visual assessment and time-consuming manual evaluation techniques are readily available, a fully objective and automated dopamine transporter quantification technique is always preferable, at least in research and follow-up investigations. Our aim was to develop a novel automated magnetic resonance imaging (MRI)-based evaluation technique of dopamine transporter SPECT images and to compare its diagnostic accuracy with those of the gold-standard visual grading and manual dopamine transporter binding quantification methods. METHODS: (123)I-FP-CIT SPECT and MRI sessions were conducted in 33 patients with PS (15 men; mean age: 60.3 ± 9.7 years) and 15 patients with ET (8 men; mean age: 54.7 ± 16.3 years). Striatal dopamine transporter binding was visually classified by 2 independent experts as normal or abnormal grade I, II and III. Caudal and putaminal specific uptake ratios were calculated by both automated MRI-based and manual evaluation techniques. RESULTS: We found almost perfect agreement (κ = 0.829) between the visual scores by the 2 observers. The automated method showed strong correlation with the visual and manual evaluation techniques and its diagnostic accuracy (sensitivity = 97.0%; specificity = 93.3%) was also comparable to these methods. The automatically determined uptake parameters showed negative correlation with the clinical severity of parkinsonism. Based on ordinal regression modelling, the automated MRI-based method could reliably determine the visual grading scores. CONCLUSION: The novel MRI-based evaluation of (123)I-FP-CIT SPECT images is useful for the differentiation of PS from ET.

[New trends and novel possibilities in the clinical use of SPECT/CT imaging]. / Újdonságok és új lehetoségek a SPECT/CT klinikai alkalmazásában.

The application of hybrid equipments and fused techniques has increasing importance in the field of imaging diagnostics. The biggest advantage of these methods is the simultaneous use of several modalities which can give data about the morphological, functional as well as molecular changes of the different diseases at the same time. The facilities, advantages and the applicability of the SPECT/CT (single photon emission computer tomograph/computer tomograph) are summarized in this paper mainly in oncologic diseases, but also in other disorders. The multimodality equipments showing the function and morphology together increase the specificity and diagnostic accuracy of the nuclear medicine methods and were found to be more efficient in the therapy effectiveness, too.