Clinical performance of Siemens digital breast tomosynthesis versus standard supplementary mammography for the assessment of screen-detected soft-tissue abnormalities: a multi-reader study.

AIM: To compare the diagnostic accuracy of standard screening images plus single-view digital breast tomosynthesis (DBT), using Siemens DBT equipment, with standard screening images plus supplementary mammographic views in non-calcific, screen-detected mammographic abnormalities. MATERIALS AND METHODS: Participants were unselected women aged 50-69 years recalled within a population-based European breast screening programme for assessment of soft-tissue mammographic abnormalities. Supplementary mammographic views (SMVs) and DBT were performed in all cases. A range of equipment was used for screening and supplementary mammography, but all DBT examinations were performed using the Siemens Mammomat Inspiration. A retrospective multi-reader study including 238 cases for whom either histology or at least 2 years' follow-up was available was performed with eight suitably accredited UK breast screening personnel reading all cases under both conditions, with temporal separation. Readers were blinded to case outcomes and findings from other examinations. Diagnostic accuracy using receiver operating characteristic (ROC) analysis was compared between screening plus SMV images and screening plus DBT images. The study was powered to detect a 3% inferiority margin in diagnostic accuracy between methods. RESULTS: The final sample with complete data available for analysis included 195 benign cases (1,560 reads) and 35 malignant cases (280 reads). The DBT method yielded a slightly higher area under the curve (AUC) value than the SMV method (0.870 versus 0.857), but the difference was not statistically significant (p=0.4890), indicating that the methods have equivalent accuracy. CONCLUSION: Siemens DBT demonstrates equivalent diagnostic accuracy according to ROC curve analysis when used in place of SMVs in screen-detected soft-tissue mammographic abnormalities.

Radiopathological features predictive of involved margins in ductal carcinoma in situ.

INTRODUCTION Ductal carcinoma in situ (DCIS) usually manifests as microcalcification on mammography but may be uncalcified. Consequently, a quarter of patients undergoing excision of a presumed pure DCIS require further surgery to re-excise margins. Patients at highest risk of margin involvement may benefit from additional preoperative assessment. METHODS A retrospective review was carried out of patients treated for screen detected, biopsy proven DCIS in a single centre over a ten-year period (1999-2009). Logistic regression analysis identified factors predictive of need for further surgery to clear margins. RESULTS Overall, 248 patients underwent surgery for DCIS (low/intermediate grade: 82, high grade: 155) and 49 (19.8%) required further surgery. High grade disease was associated with greater mammographic extent (mean: 32mm [range: 5-120mm] vs 25mm [range: 2-100mm]), p=0.009) and higher incidence of mastectomy (38% vs 24%, p=0.034). Factors predictive of involvement of surgical margins necessitating further surgery included negative oestrogen receptor status (OR: 5.2, 95% CI: 2.1-12.8, p<0.001) and mammographic extent (odds ratio [OR]: 1.6, 95% confidence interval [CI]: 1.2-2.1, p=0.004). Once size exceeded 30mm, more than 50% of patients required secondary breast surgery for margins. CONCLUSIONS Reoperation rates for DCIS increase with preoperative size on mammography and negative oestrogen receptor status on core biopsy. Patients with these risk features should be counselled accordingly and consideration should be given to the role of additional preoperative imaging.

Prognostic significance of raised cardiac troponin T in patients presenting with acute limb ischaemia.

OBJECTIVE: To study the relation between serum cardiac troponin T (cTnT) and mortality in patients presenting with acute limb ischaemia secondary to an embolism. MATERIAL AND METHODS: A two years prospective study of all patients admitted to the vascular unit with a diagnosis of acute limb ischaemia secondary to an embolism. On admission all patients had an ECG. A blood sample was taken for measurement of cTnT, CRP, serum biochemistry, full blood count and clotting. All embolectomies were performed under local anaesthesia. Patients were followed until discharge from hospital and up to twelve months after surgery. RESULTS: There were 37 patients with lower limb and 2 patients with upper limb ischaemia. Twenty four patients were female and fifteen were male, with the mean age of 76 years (50-95) for women and 84 years (77-90) for men. Seventeen patients (44%) had a raised cTnT. The patients with raised cTnT were older than those with normal cTnT [86y (77-92) vs 77y (51-95), p = 0.01, t test]. The mean cTnT was 0.20 microg/L (range: 0.11-0.27). Only two patients with raised cTnT gave a history of chest pains. All of the patients with an elevated cTnT had also raised CRP. There was no significant difference in the serum creatinine in the group of patients with elevated cTnT compared to those with normal cTnT [112 micromol/L (range 98-159) vs 119 micromol/L (range: 47-177), p = ns]. The cumulative survival for cTnT+ patients at 7 days was 53% and that of cTnT- patients was 100%. The cumulative survival for cTnT+ and cTnT- patients was statistically different (p = 0.0000, chi2 = 13.1, Log Rank test). Using regression analysis, an elevated cTnT was found to be an independent predictor of outcome. CONCLUSION: A significant proportion of patients presenting with an acutely ischaemic limb have an elevated cTnT. An elevated cTnT may be an early marker of overall disease severity and a predictor of outcome.

Responses in muscle afferent fibres of slow conduction velocity to contractions and ischaemia in the cat.

The aim of the study was to find out to what extent muscle receptors with slowly conducting afferent fibres (group III and IV) are activated by muscular contractions of moderate force, and what kind of muscle afferents could mediate the pain of ischaemic exercise. In chloralose-anaesthetized cats, the impulse activity of single afferent units from the triceps surae muscle was recorded from dorsal root filaments during muscular contractions with intact blood supply and after occlusion of the muscle artery. Two types of responses were observed to contractions without muscular ischaemia. One was characterized by sudden onset and a graded response amplitude to contractions of increasing force. In most cases stretching the muscle was also an effective stimulus. Units showing this response behaviour were labelled c.s.m (contraction-sensitive with mechanical mechanism of activation). The other response type had a more delayed onset and often outlasted the exercise period; because of the unknown mechanism of activation, units of this kind were labelled c.s.x. The proportion of c.s.m receptors was significantly higher amongst group III than amongst group IV units. During ischaemic contractions of comparable force the c.s.m and c.s.x receptors exhibited an unchanged or a decreased response amplitude. Under these conditions another receptor type (N, for nociceptive) was activated which did not respond to contractions with intact blood supply. Vigorous activations during ischaemic work were only observed in group IV receptors. The majority of the 131 group III and IV units tested did not respond to contractions at all. These contraction-insensitive (c.i.) endings probably comprised different receptor populations (nociceptors, thermoreceptors, low-threshold mechanoreceptors). It is concluded that the various central nervous effects of muscular exercise without ischaemia which are known to be due to raised activity in thin muscle afferents (e.g. cardiopulmonary adjustments, spinal locomotor reflexes) are probably produced by the c.s.m and c.s.x types. The pain of ischaemic contractions is most likely mediated by the N receptors most of which possess non-myelinated afferent fibres.

Blood sampling in very low birth weight infants receiving different levels of intensive care.

Sixty very low birth weight infants (birth weight 560-1450 g) were studied during the first 28 days of life. The infants were classified as group A (n = 19 infants who never required ventilator support), group B (n = 20 infants mechanically ventilated for minor respiratory problems), and group C (n = 21 infants ventilated for respiratory distress syndrome). Diagnostic blood sampling was measured, infants were checked for clinical symptoms and laboratory signs of anaemia 24 h before and after the transfusion of packed red cells. A total of 7998 punctures (average: 4.8 per infant per day) were performed, the mean blood loss due to diagnostic sampling was 50.3 ml/kg per 28 days (range 7-142) for all infants. A high correlation (rs = +0.91) was found between the blood volumes sampled and transfused. In group A, the mean blood loss was 24 ml/kg, and a total of 29 blood transfusions were administered. The most frequent symptoms of anaemia were poor weight gain and apnoeic spells. In group B, the mean blood loss was 60 ml/kg and a total of 97 blood transfusions were administered. In group C, the mean blood loss was 67 ml/kg and a total of 116 blood transfusions were administered. In both groups B and C, poor weight gain, pallor and distended abdomen were the most frequent symptoms of anaemia. Following the blood transfusion, haematocrit rose and blood pressure remained unchanged. The symptoms that responded most favourably to the blood transfusion were: poor weight gain, oxygen requirement, and distended abdomen. The results emphasize the need for miniaturizing laboratory techniques and monitoring blood sampling.

Calcific haemorrhagic bursitis anterior to the knee mimicking a soft tissue sarcoma: report of two cases.

We describe the radiological and pathological findings of two cases of calcific haemorrhagic bursitis, one involving the superficial infrapatellar bursa and the other the prepatellar bursa. It was the presence of dystrophic calcification within the lesion that suggested a mineralizing soft tissue sarcoma such as synovial sarcoma. As the radiographic and MR features of the two conditions can be similar but the appropriate management very different, rare calcifying haemorrhagic bursitis needs to be included in the differential diagnosis of masses adjacent to the knee joint showing calcification.