The role of 18F-FDG PET/CT in management of paraneoplastic limbic encephalitis combined with small cell lung cancer: A case report.

RATIONALE: Limbic encephalitis is one of the most common paraneoplastic neurological disorders (PND). The role of brain Fluorine-18-fluorodeoxyglucose position emission tomography/computed tomography (CT) in paraneoplastic limbic encephalitis (PLE) and of the whole body 18F-FDG PET/CT in this setting, remains still not well defined. PATIENT CONCERNS: We report a case of a patient with chronic inflammatory rheumatism, psoriasis and Hashimoto thyroiditis and subsequent appearance of static and dynamic ataxia and episodic memory deficit who was diagnosed as PLE combined with small cell lung cancer (SCLC). DIAGNOSES: The diagnosis of SCLC was made with EBUS-TBNA of a mediastinal lymph node. INTERVENTIONS: Whole-body 18F-FDG PET/CT was performed for the initial staging of SCLC, in the planning of radiotherapy treatment, to evaluate therapeutic response and in the follow-up. A dedicated brain scan was included to the same PET session. Whole-body contrast enhanced computed tomography (CT) and contrast enhanced whole-brain MRI were also performed. OUTCOMES: She was administered neoadjuvant chemioterapy with Cisplatin and Etoposide with concomitant radiotherapy treatment. Whole body 18F-FDG PET/CT showed a complete metabolic response already after 3 cycles of chemioterapy. Brain functional study showed a metabolic pattern characterized by the migration of hypermetabolism in the bilateral hippocampal areas during the therapeutic treatment, which correlated with the persistence of clinical symptoms. LESSONS: In the era of personalized medicine and targeted therapy, this case highlights the importance of the 18F-FDG PET/CT study as an accurate tool to identify PLE and to guide the diagnostic work-up of the underlying tumor. Considering that most of these are 18F-FDG avid tumors and that the 18F-FDG PET/CT scan is often added to the diagnostic work-up when screening patients for malignancy, this functional imaging can play a decisive role.

Scintimammography with a hybrid SPECT/CT imaging system.

BACKGROUND: Planar scintimammography is useful for characterizing breast lesions >10 mm. Our aim was to evaluate Tc-99m sestamibi scintimammography with a hybrid (SPECTICT) device for functional anatomical mapping (FAM). PATIENTS AND METHODS: Three planar images and a chest SPECT/CT were performed with a hybrid device in 53 patients with mammographically suspicious lesions. The final histopathological diagnosis was obtained after surgery. RESULTS: The planar images were positive in 27 out of 37 carcinomas (sensitivity 73%) and the SPECT/CT in 33 (sensitivity 89.2%). The sensitivity of planar imaging and SPECT/CT was 42.9% and 71.4% in cancers < or =10 mm, and 91.3%, and 100% in cancers >10 mm, respectively. The specificity was 93.8% for both planar and SPECT/CT imaging; accuracy was 79.2% for planar scans and 90.6% for SPECT/CT. FAM was useful in providing a precise anatomical localisation of the SPECT findings. CONCLUSION: SPECT/CT scintimammography using a hybrid device is able to detect breast cancer, showing a sensitivity higher than that of planar images, especially for small cancers.

Single-photon emission computed tomography/computed tomography in brain tumors.

Anatomic imaging procedures (computed tomography [CT] and magnetic resonance imaging [MRI]) have become essential tools for brain tumor assessment. Functional images (positron emission tomography [PET] and single-photon emission computed tomography [SPECT]) can provide additional information useful during the diagnostic workup to determine the degree of malignancy and as a substitute or guide for biopsy. After surgery and/or radiotherapy, nuclear medicine examinations are essential to assess persistence of tumor, to differentiate recurrence from radiation necrosis and gliosis, and to monitor the disease. The combination of functional images with anatomic ones is of the utmost importance for a full evaluation of these patients, which can be obtained by means of imaging fusion. Despite the fast-growing diffusion of PET, in most cases of brain tumors, SPECT studies are adequate and provide results that parallel those obtained with PET. The main limitation of SPECT imaging with brain tumor-seeking radiopharmaceuticals is the lack of precise anatomic details; this drawback is overcome by the fusion with morphological studies that provide an anatomic map to scintigraphic data. In the past, software-based fusion of independently performed SPECT and CT or MRI demonstrated usefulness for brain tumor assessment, but this process is often time consuming and not practical for everyday nuclear medicine studies. The recent development of dual-modality integrated imaging systems, which allow the acquisition of SPECT and CT images in the same scanning session, and their co-registration by means of the hardware, has facilitated this process. In SPECT studies of brain tumors with various radiopharmaceuticals, fused images are helpful in providing the precise localization of neoplastic lesions, and in excluding the disease in sites of physiologic tracer uptake. This information is useful for optimizing diagnosis, therapy monitoring, and radiotherapy treatment planning, with a positive impact on patient management.

123I-FP-CIT in progressive supranuclear palsy and in Parkinson's disease: a SPECT semiquantitative study.

BACKGROUND AND AIM: It is still debated whether or not I-FP-CIT single photon emission computerized tomography (SPECT) is able to differentiate between Parkinson's disease and progressive supranuclear palsy (PSP). Our aim was to use SPECT semiquantitative analysis to assess the capacity of I-FP-CIT to characterize Parkinson's disease versus PSP. PATIENTS AND METHODS: Twenty-one Parkinson's disease patients, 15 disease duration- and age-matched PSP patients and 20 age-matched healthy controls were included in this study. SPECT imaging was always performed at 4 h post-injection. The ratios of striatal (S) to non-specific occipital (O) binding for the entire striatum (S/O), caudate nuclei (C/O), putamina (P/O) were calculated in both the basal ganglia. The asymmetric index (AI) for the whole striatum was also calculated for Parkinson's disease and PSP. RESULTS: Compared to healthy controls, S/O, C/O and P/O were significantly reduced (P<0.001) both in Parkinson's disease (-46%, -43%, -49%, contralaterally to the most affected side; -41%, -37%, -41%, ipsilaterally) and in PSP (-58%, -57%, -59%, contralaterally; -58%, -57%, -59%, ipsilaterally). S/O, C/O and P/O ratio values were significantly (P<0.001) lower in PSP patients when compared to Parkinson's disease group. The asymmetric index (AI) was significantly higher (P<0.001) in Parkinson's disease than in PSP (AI: 23.6%+/-15.07% vs. 9.66%+/-5.83), but with an overlap between the two groups. CONCLUSION: Our results confirm that I-FP-CIT SPECT is clinically useful for detecting nigrostriatal degeneration both in Parkinson's disease and PSP. Moreover, in our series, semiquantitative analysis using I-FP-CIT SPECT allowed Parkinson's disease and PSP to be discriminated because PSP patients presented a more severe and symmetric dopamine transporter loss, and the results for S/O were more accurate.

Usefulness of SPECT/CT with a hybrid camera for the functional anatomical mapping of primary brain tumors by [Tc99m] tetrofosmin.

The aims of this study were to assess the clinical usefulness of [Tc-99m] tetrofosmin (TF) single photon emission computed tomography (SPECT) and X-ray transmission computed tomography (CT), performed simultaneously with a hybrid imaging device for the functional anatomical mapping of brain tumors and to evaluate the additional information of SPECT/CT when compared to SPECT alone. Thirty (30) patients were studied: 20 were evaluated before undergoing surgery and 10 after surgery and before radiotherapy planning. The acquisition of both functional (SPECT) and morphologic (CT) images were obtained in a single session. SPECT images were firstly evaluated alone and then reinterpreted by adding the anatomical (CT) planes. Fusion imaging was successfully obtained in all patients with precise correspondence between SPECT and CT slices. SPECT/CT had a significant clinical impact in 13 (43.3%) of 30 cases; in particular, SPECT/CT accurately characterized eight lesions near sites of physiological uptake (i.e., four near ventricles/choroids plexus, three near venous sinuses, one near the skull) and localized viable tumor tissue in 5 patients evaluated after surgery. SPECT/CT with TF using this hybrid device represents a useful clinical tool in brain tumor imaging, both correctly categorizing focal areas near sites of physiological uptake and localizing viable tumor tissue after surgery.

The effect of levodopa therapy on dopamine transporter SPECT imaging with( 123)I-FP-CIT in patients with Parkinson's disease.

PURPOSE: The aim of this study was to evaluate, by means of (123)I-FP-CIT SPECT, the effect of chronic treatment with levodopa on striatal dopamine transporter (DAT) in patients with Parkinson's disease. METHODS: Fifteen patients under stable levodopa/carbidopa monotherapy were imaged twice: at baseline on medication and after at least 20 days of treatment wash-out. DAT levels were assessed from SPECT imaging for the entire striatum, the right and left striatum, the right and left putamen and the right and left caudate, as a ratio of regional brain activities using the formula: (striatal region of interest-occipital)/occipital. RESULTS: During levodopa wash-out, despite a worsening in patients' clinical disability (H&Y mean stage 2.53+/-0.58 versus 1.73+/-0.45 on therapy, p<0.001), striatal( 123)I-FP-CIT levels were not significantly different from those at baseline in any of the brain regions examined. CONCLUSION: The results of this study suggest that levodopa does not affect( 123)I-FP-CIT brain imaging and confirm that it is not necessary to withdraw this medication to measure DAT levels with SPECT.

123I-FP-CIT semi-quantitative SPECT detects preclinical bilateral dopaminergic deficit in early Parkinson's disease with unilateral symptoms.

BACKGROUND AND AIM: 123I-FP-CIT SPECT has been successfully used to detect the loss of dopaminergic nigrostriatal neurons in Parkinson's disease at an early stage. In this study we evaluated the capacity of 123I-FP-CIT SPECT to assess bilateral dopamine transporter (DAT) loss in de-novo hemi-Parkinson's disease (PD) patients with one-sided clinical symptoms. PATIENTS AND METHODS: Twenty-nine de-novo hemi-PD patients at an early stage (Hoehn & Yahr stage 1) and 18 gender and age matched healthy subjects were studied. SPECT imaging was always performed at 4 h post-injection. The ratios of striatal (S) to non-specific occipital (O) binding for the entire striatum (S/O), caudate nuclei (C/O), putamina (P(put)/O), and the putamen to caudate nucleus index (P(put)/C) were calculated in both the basal ganglia. RESULTS: In PD patients S/O, C/O and P(put)/O ratio values contralateral to the clinically affected side were significantly lower (P<0.001) than in the control group (-38%, -34% and -42%, respectively). A significant reduction (P<0.001) of the striatal binding ratios was also found ipsilaterally (S/O, -31%; C/O, -28%; P(put)/O, -33%). The P(put)/C index was also bilaterally significantly reduced (P<0.01). DAT loss was significantly greater (P<0.001) in the contralateral than in the ipsilateral S; and putamen bilaterally presented a higher dopaminergic deficit than did caudate. CONCLUSION: Our results indicate that semi-quantitative 123I-FP-CIT SPECT detects a bilateral dopaminergic deficit in early PD with unilateral symptoms and preclinical DAT loss in the ipsilateral striatal binding, corresponding to the side not yet affected by motor signs. Semi-quantitative analysis may thus be used to diagnose PD at an early stage as well as to identify individuals developing bilateral dopaminergic damage.

Is SPECT/CT with a hybrid camera useful to improve scintigraphic imaging interpretation?

OBJECTIVES: To assess the usefulness of a hybrid imaging system (single-photon emission computed tomography/computed tomography, SPECT/CT) for functional anatomical mapping (FAM) using various radiotracers and the additional value of fused SPECT/CT images compared with SPECT alone. METHODS: Eighty-one consecutive patients studied for various clinical situations were evaluated: 10 with 111In-pentetreotide, four with 123I-meta-iodobenzylguanidine (I-MIBG), five with 99mTc-labelled red blood cells, two with 99mTc-antigranulocyte antibodies, four with 99mTc-nanocolloids, 10 with 67Ga, seven with 99mTc-methylene diphosphonate (99mTc-MDP), nine with 99mTc-sestamibi, 21 with 99mTc-tetrofosmin, two with 201Tl, three with 99mTc-ethylcysteinate dimer (ECD), one with 99mTc-hexamethylpropyleneamine oxime (99mTc-HMPAO) and three with 123I-N-w-fluoropropyl-2-beta-carbomethoxy-3-beta-(4-iodophenyl) nortropanel (FPCIT). The acquisition of both anatomical (CT) and functional (SPECT) data was performed during a single session. SPECT data were first interpreted alone and then re-evaluated with the addition of FAM. RESULTS: Transmission anatomical maps allowed for the precise anatomical localization of SPECT images in 79 of the 81 cases. SPECT/CT had a significant impact on the results in 33 (40.7%) of the 81 patients: FAM provided the correct localization of SPECT findings in 23 cases, allowed the definition of the functional significance of CT lesions in two and enabled the exclusion of disease in sites of physiological tracer uptake in eight. CONCLUSIONS: SPECT/CT with this hybrid system is a feasible technique yielding co-registered dual-modality images. FAM allows a more precise interpretation of scintigraphic studies in several cases and fused images can improve the diagnostic accuracy of SPECT in various clinical situations.

Technetium-99m-labelled red blood cell imaging in the diagnosis of hepatic haemangiomas: the role of SPECT/CT with a hybrid camera.

Delayed liver single-photon emission computed tomography (SPECT) after (99m)Tc red blood cell (RBC) labelling is helpful in detecting hepatic haemangiomas; however, diagnosis can be difficult when lesions are situated adjacent to structures like the inferior vena cava, the heart or hepatic vessels, where blood activity persists. The aims of this study were to evaluate the usefulness of RBC SPECT and transmission computed tomography (RBC SPECT/CT) performed simultaneously with a hybrid imaging system for correct characterisation of hepatic lesions in patients with suspected haemangioma, and to assess the additional value of fused images compared with SPECT alone. Twelve patients with 24 liver lesions were studied. The acquisitions of both anatomical (CT) and functional (SPECT) data were performed during a single session. SPECT images were first interpreted alone and then re-evaluated after adding the transmission anatomical maps. Image fusion was successful in all patients, with perfect correspondence between SPECT and CT data, allowing the precise anatomical localisation of sites of increased blood pool activity. SPECT/CT had a significant impact on results in four patients (33.3%) with four lesions defined as indeterminate on SPECT images, accurately characterising the hot spot foci located near vascular structures. In conclusion, RBC SPECT/CT imaging using this hybrid SPECT/CT system is feasible and useful in the identification or exclusion of suspected hepatic haemangiomas located near regions with high vascular activity.

Control results on a sample of patients subjected to total thyroidectomy for papillary carcinoma: proposal for a personal diagnostic-therapeutic follow-up.

Well-differentiated thyroid neoplasms may be included among the most frequently occurring thyroid carcinomas. Papillary ca. is without doubt the best behaved type. The aim of the present work is to perform a retrospective case history study to assess patients with con papillary ca. who have been treated surgically over the last 17 years and have been subjected to periodic checks. A sample of patients was therefore extrapolated who had all undergone total thyroidectomy for papillary ca. of the thyroid. The incidence of local recurrence of the disease was verified, together with the results at distance. Furthermore, the assessments performed were evaluated and compared. From the sample of patients observed we inferred that papillary carcinoma of the thyroid can have a good prognosis over time provided periodic random checks are carried out.