This paper presents the results of phantom studies to investigate possible dose reduction in relation to image quality in head examinations. The studies were performed using five single-slice computed tomography (CT) scanners. Beginning from the manufacturer's protocols (i.e. default protocols in the scanner software) for routine head (adult) examinations, the values of kV(p), anode current and time were modified. Low-contrast resolution and spatial resolution were controlled using a Catphan 424 phantom. Radiation dose was checked using a polymethylmethacrylate phantom and a pencil ionisation chamber. It was found that CT dose index may be reduced up to three times with practically no loss of image quality.

IntroductionCore needle biopsy is a preferable breast biopsy technique under ultrasound guidance. However, fine-needle biopsy is considered equally popular.Aim of the studyTo redefine the role of fine-needle aspiration biopsy (FNAB) in the diagnosis of breast lesions.Material and methodsWe retrospectively analysed the medical records of 680 patients who underwent breast ultrasound examination. In most cases, no pathologic structures were observed within the mammary glands. In 321 patients, the presence of focal lesions was revealed, and 107 patients in this group qualified for FNAB according to current recommendations. Patients with suspicious smears were referred for core needle or surgical biopsy. Patients with benign cytological smears underwent repeated ultrasound checks at 6-month intervals during the following year.ResultsAll the smears were diagnostic. The vast majority of the results were categorised as benign lesions. Cancer cells were detected in six women. In one patient the lesion was classified as suspicious, probably malignant. In all of these cases, open biopsy was performed, and histopathological examination confirmed the presence of a malignant tumour. The patients were given appropriate oncological treatment. For women with benign or suspicious, but probably benign, lesions, breast ultrasound was performed twice at six-month intervals. Control tests showed no significant changes compared to the baseline examination. None of the patients required extensive additional diagnostic tests.ConclusionsFNAB is a reliable method of assessing pathologic lesions in mammary glands.

BACKGROUND AND PURPOSE:A key angiographic sign observed in patients with spinal vascular malformations is the absence of a normal venous phase. While this finding alone is often believed to rule out a lesion impacting the perimedullary venous drainage, the observation of a venous phase in several patients with vascular malformations led us to reconsider the validity of that sign.