Leydig cell tumour of the ovary localised with positron emission tomography/computed tomography.

Androgen-producing ovarian tumours can lead to assessment difficulties because of their small size. We present a case of virilising steroid cell ovarian tumour in a 41-year-old woman localised with Fluorine-18-Deoxyglucose Positron Emission Tomography/Computed Tomography ((18)FDG-PET/CT). Although the biochemical evaluation pointed to an ovarian source of androgen, diagnostic attempts to localise the source of hyperandrogenism with transvaginal ultrasound (US), and magnetic resonance imaging (MRI) of pelvis failed. Additional evaluation with (18)FDG-PET/CT showed an increased uptake in the right ovary. A laparoscopic right oophorectomy was performed and histopathology examination revealed a 1.2-cm Leydig cell tumour. The patient showed regression of clinical signs.

Correlation of radiation dose and heart rate in dual-source computed tomography coronary angiography.

BACKGROUND: Computed tomography coronary angiography (CTCA) has been widely used since the introduction of 64-slice scanners and dual-source CT technology, but the relatively high radiation dose remains a major concern. PURPOSE: To evaluate the relationship between radiation exposure and heart rate (HR), in dual-source CTCA. MATERIAL AND METHODS: Data from 218 CTCA examinations, performed with a dual-source 64-slices scanner, were statistically evaluated. Effective radiation dose, expressed in mSv, was calculated as the product of the dose-length product (DLP) times a conversion coefficient for the chest (mSv = DLPx0.017). Heart rate range and mean heart rate, expressed in beats per minute (bpm) of each individual during CTCA, were also provided by the system. Statistical analysis of effective dose and heart rate data was performed by using Pearson correlation coefficient and two-sample t-test. RESULTS: Mean HR and effective dose were found to have a borderline positive relationship. Individuals with a mean HR >65 bpm observed to receive a statistically significant higher effective dose as compared to those with a mean HR ≤65 bpm. Moreover, a strong correlation between effective dose and variability of HR of more than 20 bpm was observed. CONCLUSION: Dual-source CT scanners are considered to have the capability to provide diagnostic examinations even with high HR and arrhythmias. However, it is desirable to keep the mean heart rate below 65 bpm and heart rate fluctuation less than 20 bpm in order to reduce the radiation exposure.

18F-fluorothymidine PET imaging in gliomas: an update.

Brain neoplasms constitute a group of tumors with discrete differentiation grades, and therefore, course of disease and prognosis. Magnetic resonance imaging (MRI) remains the gold standard method for the investigation of central nervous system tumors. However, MRI suffers certain limitations, especially if radiation therapy or chemotherapy has been previously applied. On the other hand, given the development of newer radiopharmaceuticals, positron emission tomography (PET) aims to a better investigation of brain tumors, assisting in the clinical management of the patients. In the present review, the potential contribution of radiolabeled fluorothymidine (FLT) imaging for the evaluation of brain tumors will be discussed. In particular, we will present the role of FLT-PET imaging in the depiction of well and poorly differentiated lesions, the assessment of patient prognosis and treatment response, and the recognition of disease recurrence. Moreover, related semi-quantitative and kinetic parameters will be discussed.

FLT PET/CT in a Case of Demyelinating Disease.

A 32-year-old woman, with spare previous medical history, presented with neurological symptoms of numbness and diplopia. The patient underwent brain MRI, which revealed a lesion of abnormal signal in the midbrain that could be attributed to subacute stroke; however, consecutive MRIs revealed multiple lesions of abnormal signal pointing to demyelinating disease. During symptoms investigation and MRI findings assessment, the patient underwent a FLT PET/CT examination, which revealed lesions of increased FLT uptake, probably indicating active disease and blood-brain barrier disruption.

Coronary artery anomalies in adults: imaging at dual source CT coronary angiography.

Congenital abnormalities of the coronary arteries have an incidence of 1%, and most of these are benign. However, a small number are associated with myocardial ischaemia and sudden death. Various imaging modalities are available for coronary artery assessment. Recently, multi-detector CT has emerged as an accurate diagnostic tool for defining coronary artery anomalies. The purpose of this pictorial essay is to review the dual source CT appearance of congenital anomalies of the coronary arteries in adults.

Imaging of coronary artery bypass grafts by computed tomography coronary angiography.

In recent years, computed tomography coronary angiography is commonly performed as a follow-up examination after coronary artery bypass graft surgery. Coronary grafts owing to their minimal motion are well visualized by computed tomography coronary angiography, allowing radiologists to assess their patency noninvasively with very high diagnostic accuracy. The purpose of this pictorial essay is to provide an excellent overview of the anatomy and findings concerning coronary artery bypass grafts.